Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* i2c-core.c - a device driver for the iic-bus interface */ |
2 | /* ------------------------------------------------------------------------- */ | |
3 | /* Copyright (C) 1995-99 Simon G. Vogl | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
ca1f8da9 | 13 | GNU General Public License for more details. */ |
1da177e4 LT |
14 | /* ------------------------------------------------------------------------- */ |
15 | ||
96de0e25 | 16 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 17 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b | 18 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
7c81c60f | 19 | Jean Delvare <jdelvare@suse.de> |
0826374b | 20 | Mux support by Rodolfo Giometti <giometti@enneenne.com> and |
687b81d0 WS |
21 | Michael Lawnick <michael.lawnick.ext@nsn.com> |
22 | OF support is copyright (c) 2008 Jochen Friedrich <jochen@scram.de> | |
23 | (based on a previous patch from Jon Smirl <jonsmirl@gmail.com>) and | |
24 | (c) 2013 Wolfram Sang <wsa@the-dreams.de> | |
17f4a5c4 WS |
25 | I2C ACPI code Copyright (C) 2014 Intel Corp |
26 | Author: Lan Tianyu <tianyu.lan@intel.com> | |
4b1acc43 | 27 | I2C slave support (c) 2014 by Wolfram Sang <wsa@sang-engineering.com> |
687b81d0 | 28 | */ |
1da177e4 | 29 | |
b4e2f6ac | 30 | #include <dt-bindings/i2c/i2c.h> |
53feedf8 WS |
31 | #include <asm/uaccess.h> |
32 | #include <linux/acpi.h> | |
33 | #include <linux/clk/clk-conf.h> | |
34 | #include <linux/completion.h> | |
5f9296ba | 35 | #include <linux/delay.h> |
53feedf8 | 36 | #include <linux/err.h> |
1da177e4 | 37 | #include <linux/errno.h> |
5f9296ba | 38 | #include <linux/gpio.h> |
53feedf8 | 39 | #include <linux/hardirq.h> |
1da177e4 | 40 | #include <linux/i2c.h> |
1da177e4 | 41 | #include <linux/idr.h> |
53feedf8 WS |
42 | #include <linux/init.h> |
43 | #include <linux/irqflags.h> | |
44 | #include <linux/jump_label.h> | |
45 | #include <linux/kernel.h> | |
46 | #include <linux/module.h> | |
b3585e4f | 47 | #include <linux/mutex.h> |
959e85f7 | 48 | #include <linux/of_device.h> |
53feedf8 | 49 | #include <linux/of.h> |
687b81d0 | 50 | #include <linux/of_irq.h> |
f48c767c | 51 | #include <linux/pm_domain.h> |
53feedf8 | 52 | #include <linux/pm_runtime.h> |
3fffd128 | 53 | #include <linux/pm_wakeirq.h> |
e1dba01c | 54 | #include <linux/property.h> |
53feedf8 WS |
55 | #include <linux/rwsem.h> |
56 | #include <linux/slab.h> | |
1da177e4 | 57 | |
9c1600ed DB |
58 | #include "i2c-core.h" |
59 | ||
d9a83d62 DH |
60 | #define CREATE_TRACE_POINTS |
61 | #include <trace/events/i2c.h> | |
1da177e4 | 62 | |
da899f55 WS |
63 | #define I2C_ADDR_OFFSET_TEN_BIT 0xa000 |
64 | #define I2C_ADDR_OFFSET_SLAVE 0x1000 | |
65 | ||
6629dcff | 66 | /* core_lock protects i2c_adapter_idr, and guarantees |
35fc37f8 | 67 | that device detection, deletion of detected devices, and attach_adapter |
19baba4c | 68 | calls are serialized */ |
caada32a | 69 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
70 | static DEFINE_IDR(i2c_adapter_idr); |
71 | ||
4f8cf824 | 72 | static struct device_type i2c_client_type; |
4735c98f | 73 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a | 74 | |
d9a83d62 | 75 | static struct static_key i2c_trace_msg = STATIC_KEY_INIT_FALSE; |
95026658 | 76 | static bool is_registered; |
d9a83d62 DH |
77 | |
78 | void i2c_transfer_trace_reg(void) | |
79 | { | |
80 | static_key_slow_inc(&i2c_trace_msg); | |
81 | } | |
82 | ||
83 | void i2c_transfer_trace_unreg(void) | |
84 | { | |
85 | static_key_slow_dec(&i2c_trace_msg); | |
86 | } | |
87 | ||
17f4a5c4 WS |
88 | #if defined(CONFIG_ACPI) |
89 | struct acpi_i2c_handler_data { | |
90 | struct acpi_connection_info info; | |
91 | struct i2c_adapter *adapter; | |
92 | }; | |
93 | ||
94 | struct gsb_buffer { | |
95 | u8 status; | |
96 | u8 len; | |
97 | union { | |
98 | u16 wdata; | |
99 | u8 bdata; | |
100 | u8 data[0]; | |
101 | }; | |
102 | } __packed; | |
103 | ||
166c2ba3 MW |
104 | struct acpi_i2c_lookup { |
105 | struct i2c_board_info *info; | |
106 | acpi_handle adapter_handle; | |
107 | acpi_handle device_handle; | |
108 | }; | |
17f4a5c4 | 109 | |
166c2ba3 MW |
110 | static int acpi_i2c_find_address(struct acpi_resource *ares, void *data) |
111 | { | |
112 | struct acpi_i2c_lookup *lookup = data; | |
113 | struct i2c_board_info *info = lookup->info; | |
114 | struct acpi_resource_i2c_serialbus *sb; | |
115 | acpi_handle adapter_handle; | |
116 | acpi_status status; | |
17f4a5c4 | 117 | |
166c2ba3 MW |
118 | if (info->addr || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) |
119 | return 1; | |
120 | ||
121 | sb = &ares->data.i2c_serial_bus; | |
122 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) | |
123 | return 1; | |
124 | ||
125 | /* | |
126 | * Extract the ResourceSource and make sure that the handle matches | |
127 | * with the I2C adapter handle. | |
128 | */ | |
129 | status = acpi_get_handle(lookup->device_handle, | |
130 | sb->resource_source.string_ptr, | |
131 | &adapter_handle); | |
132 | if (ACPI_SUCCESS(status) && adapter_handle == lookup->adapter_handle) { | |
133 | info->addr = sb->slave_address; | |
134 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
135 | info->flags |= I2C_CLIENT_TEN; | |
17f4a5c4 WS |
136 | } |
137 | ||
17f4a5c4 WS |
138 | return 1; |
139 | } | |
140 | ||
141 | static acpi_status acpi_i2c_add_device(acpi_handle handle, u32 level, | |
142 | void *data, void **return_value) | |
143 | { | |
144 | struct i2c_adapter *adapter = data; | |
145 | struct list_head resource_list; | |
166c2ba3 MW |
146 | struct acpi_i2c_lookup lookup; |
147 | struct resource_entry *entry; | |
17f4a5c4 WS |
148 | struct i2c_board_info info; |
149 | struct acpi_device *adev; | |
150 | int ret; | |
151 | ||
152 | if (acpi_bus_get_device(handle, &adev)) | |
153 | return AE_OK; | |
154 | if (acpi_bus_get_status(adev) || !adev->status.present) | |
155 | return AE_OK; | |
156 | ||
157 | memset(&info, 0, sizeof(info)); | |
ce793486 | 158 | info.fwnode = acpi_fwnode_handle(adev); |
17f4a5c4 | 159 | |
166c2ba3 | 160 | memset(&lookup, 0, sizeof(lookup)); |
8eb5c87a | 161 | lookup.adapter_handle = ACPI_HANDLE(&adapter->dev); |
166c2ba3 MW |
162 | lookup.device_handle = handle; |
163 | lookup.info = &info; | |
164 | ||
165 | /* | |
166 | * Look up for I2cSerialBus resource with ResourceSource that | |
167 | * matches with this adapter. | |
168 | */ | |
17f4a5c4 WS |
169 | INIT_LIST_HEAD(&resource_list); |
170 | ret = acpi_dev_get_resources(adev, &resource_list, | |
166c2ba3 | 171 | acpi_i2c_find_address, &lookup); |
17f4a5c4 WS |
172 | acpi_dev_free_resource_list(&resource_list); |
173 | ||
174 | if (ret < 0 || !info.addr) | |
175 | return AE_OK; | |
176 | ||
166c2ba3 MW |
177 | /* Then fill IRQ number if any */ |
178 | ret = acpi_dev_get_resources(adev, &resource_list, NULL, NULL); | |
179 | if (ret < 0) | |
180 | return AE_OK; | |
181 | ||
182 | resource_list_for_each_entry(entry, &resource_list) { | |
183 | if (resource_type(entry->res) == IORESOURCE_IRQ) { | |
184 | info.irq = entry->res->start; | |
185 | break; | |
186 | } | |
187 | } | |
188 | ||
189 | acpi_dev_free_resource_list(&resource_list); | |
190 | ||
17f4a5c4 WS |
191 | adev->power.flags.ignore_parent = true; |
192 | strlcpy(info.type, dev_name(&adev->dev), sizeof(info.type)); | |
193 | if (!i2c_new_device(adapter, &info)) { | |
194 | adev->power.flags.ignore_parent = false; | |
195 | dev_err(&adapter->dev, | |
196 | "failed to add I2C device %s from ACPI\n", | |
197 | dev_name(&adev->dev)); | |
198 | } | |
199 | ||
200 | return AE_OK; | |
201 | } | |
202 | ||
166c2ba3 MW |
203 | #define ACPI_I2C_MAX_SCAN_DEPTH 32 |
204 | ||
17f4a5c4 WS |
205 | /** |
206 | * acpi_i2c_register_devices - enumerate I2C slave devices behind adapter | |
207 | * @adap: pointer to adapter | |
208 | * | |
209 | * Enumerate all I2C slave devices behind this adapter by walking the ACPI | |
210 | * namespace. When a device is found it will be added to the Linux device | |
211 | * model and bound to the corresponding ACPI handle. | |
212 | */ | |
213 | static void acpi_i2c_register_devices(struct i2c_adapter *adap) | |
214 | { | |
17f4a5c4 WS |
215 | acpi_status status; |
216 | ||
8eb5c87a | 217 | if (!has_acpi_companion(&adap->dev)) |
17f4a5c4 WS |
218 | return; |
219 | ||
166c2ba3 MW |
220 | status = acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, |
221 | ACPI_I2C_MAX_SCAN_DEPTH, | |
17f4a5c4 WS |
222 | acpi_i2c_add_device, NULL, |
223 | adap, NULL); | |
224 | if (ACPI_FAILURE(status)) | |
225 | dev_warn(&adap->dev, "failed to enumerate I2C slaves\n"); | |
226 | } | |
227 | ||
228 | #else /* CONFIG_ACPI */ | |
229 | static inline void acpi_i2c_register_devices(struct i2c_adapter *adap) { } | |
230 | #endif /* CONFIG_ACPI */ | |
231 | ||
232 | #ifdef CONFIG_ACPI_I2C_OPREGION | |
233 | static int acpi_gsb_i2c_read_bytes(struct i2c_client *client, | |
234 | u8 cmd, u8 *data, u8 data_len) | |
235 | { | |
236 | ||
237 | struct i2c_msg msgs[2]; | |
238 | int ret; | |
239 | u8 *buffer; | |
240 | ||
241 | buffer = kzalloc(data_len, GFP_KERNEL); | |
242 | if (!buffer) | |
243 | return AE_NO_MEMORY; | |
244 | ||
245 | msgs[0].addr = client->addr; | |
246 | msgs[0].flags = client->flags; | |
247 | msgs[0].len = 1; | |
248 | msgs[0].buf = &cmd; | |
249 | ||
250 | msgs[1].addr = client->addr; | |
251 | msgs[1].flags = client->flags | I2C_M_RD; | |
252 | msgs[1].len = data_len; | |
253 | msgs[1].buf = buffer; | |
254 | ||
255 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
256 | if (ret < 0) | |
257 | dev_err(&client->adapter->dev, "i2c read failed\n"); | |
258 | else | |
259 | memcpy(data, buffer, data_len); | |
260 | ||
261 | kfree(buffer); | |
262 | return ret; | |
263 | } | |
264 | ||
265 | static int acpi_gsb_i2c_write_bytes(struct i2c_client *client, | |
266 | u8 cmd, u8 *data, u8 data_len) | |
267 | { | |
268 | ||
269 | struct i2c_msg msgs[1]; | |
270 | u8 *buffer; | |
271 | int ret = AE_OK; | |
272 | ||
273 | buffer = kzalloc(data_len + 1, GFP_KERNEL); | |
274 | if (!buffer) | |
275 | return AE_NO_MEMORY; | |
276 | ||
277 | buffer[0] = cmd; | |
278 | memcpy(buffer + 1, data, data_len); | |
279 | ||
280 | msgs[0].addr = client->addr; | |
281 | msgs[0].flags = client->flags; | |
282 | msgs[0].len = data_len + 1; | |
283 | msgs[0].buf = buffer; | |
284 | ||
285 | ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs)); | |
286 | if (ret < 0) | |
287 | dev_err(&client->adapter->dev, "i2c write failed\n"); | |
288 | ||
289 | kfree(buffer); | |
290 | return ret; | |
291 | } | |
292 | ||
293 | static acpi_status | |
294 | acpi_i2c_space_handler(u32 function, acpi_physical_address command, | |
295 | u32 bits, u64 *value64, | |
296 | void *handler_context, void *region_context) | |
297 | { | |
298 | struct gsb_buffer *gsb = (struct gsb_buffer *)value64; | |
299 | struct acpi_i2c_handler_data *data = handler_context; | |
300 | struct acpi_connection_info *info = &data->info; | |
301 | struct acpi_resource_i2c_serialbus *sb; | |
302 | struct i2c_adapter *adapter = data->adapter; | |
7ef85f5f | 303 | struct i2c_client *client; |
17f4a5c4 WS |
304 | struct acpi_resource *ares; |
305 | u32 accessor_type = function >> 16; | |
306 | u8 action = function & ACPI_IO_MASK; | |
4470c725 | 307 | acpi_status ret; |
17f4a5c4 WS |
308 | int status; |
309 | ||
310 | ret = acpi_buffer_to_resource(info->connection, info->length, &ares); | |
311 | if (ACPI_FAILURE(ret)) | |
312 | return ret; | |
313 | ||
7ef85f5f JN |
314 | client = kzalloc(sizeof(*client), GFP_KERNEL); |
315 | if (!client) { | |
316 | ret = AE_NO_MEMORY; | |
317 | goto err; | |
318 | } | |
319 | ||
17f4a5c4 WS |
320 | if (!value64 || ares->type != ACPI_RESOURCE_TYPE_SERIAL_BUS) { |
321 | ret = AE_BAD_PARAMETER; | |
322 | goto err; | |
323 | } | |
324 | ||
325 | sb = &ares->data.i2c_serial_bus; | |
326 | if (sb->type != ACPI_RESOURCE_SERIAL_TYPE_I2C) { | |
327 | ret = AE_BAD_PARAMETER; | |
328 | goto err; | |
329 | } | |
330 | ||
7ef85f5f JN |
331 | client->adapter = adapter; |
332 | client->addr = sb->slave_address; | |
17f4a5c4 WS |
333 | |
334 | if (sb->access_mode == ACPI_I2C_10BIT_MODE) | |
7ef85f5f | 335 | client->flags |= I2C_CLIENT_TEN; |
17f4a5c4 WS |
336 | |
337 | switch (accessor_type) { | |
338 | case ACPI_GSB_ACCESS_ATTRIB_SEND_RCV: | |
339 | if (action == ACPI_READ) { | |
7ef85f5f | 340 | status = i2c_smbus_read_byte(client); |
17f4a5c4 WS |
341 | if (status >= 0) { |
342 | gsb->bdata = status; | |
343 | status = 0; | |
344 | } | |
345 | } else { | |
7ef85f5f | 346 | status = i2c_smbus_write_byte(client, gsb->bdata); |
17f4a5c4 WS |
347 | } |
348 | break; | |
349 | ||
350 | case ACPI_GSB_ACCESS_ATTRIB_BYTE: | |
351 | if (action == ACPI_READ) { | |
7ef85f5f | 352 | status = i2c_smbus_read_byte_data(client, command); |
17f4a5c4 WS |
353 | if (status >= 0) { |
354 | gsb->bdata = status; | |
355 | status = 0; | |
356 | } | |
357 | } else { | |
7ef85f5f | 358 | status = i2c_smbus_write_byte_data(client, command, |
17f4a5c4 WS |
359 | gsb->bdata); |
360 | } | |
361 | break; | |
362 | ||
363 | case ACPI_GSB_ACCESS_ATTRIB_WORD: | |
364 | if (action == ACPI_READ) { | |
7ef85f5f | 365 | status = i2c_smbus_read_word_data(client, command); |
17f4a5c4 WS |
366 | if (status >= 0) { |
367 | gsb->wdata = status; | |
368 | status = 0; | |
369 | } | |
370 | } else { | |
7ef85f5f | 371 | status = i2c_smbus_write_word_data(client, command, |
17f4a5c4 WS |
372 | gsb->wdata); |
373 | } | |
374 | break; | |
375 | ||
376 | case ACPI_GSB_ACCESS_ATTRIB_BLOCK: | |
377 | if (action == ACPI_READ) { | |
7ef85f5f | 378 | status = i2c_smbus_read_block_data(client, command, |
17f4a5c4 WS |
379 | gsb->data); |
380 | if (status >= 0) { | |
381 | gsb->len = status; | |
382 | status = 0; | |
383 | } | |
384 | } else { | |
7ef85f5f | 385 | status = i2c_smbus_write_block_data(client, command, |
17f4a5c4 WS |
386 | gsb->len, gsb->data); |
387 | } | |
388 | break; | |
389 | ||
390 | case ACPI_GSB_ACCESS_ATTRIB_MULTIBYTE: | |
391 | if (action == ACPI_READ) { | |
7ef85f5f | 392 | status = acpi_gsb_i2c_read_bytes(client, command, |
17f4a5c4 WS |
393 | gsb->data, info->access_length); |
394 | if (status > 0) | |
395 | status = 0; | |
396 | } else { | |
7ef85f5f | 397 | status = acpi_gsb_i2c_write_bytes(client, command, |
17f4a5c4 WS |
398 | gsb->data, info->access_length); |
399 | } | |
400 | break; | |
401 | ||
402 | default: | |
403 | pr_info("protocol(0x%02x) is not supported.\n", accessor_type); | |
404 | ret = AE_BAD_PARAMETER; | |
405 | goto err; | |
406 | } | |
407 | ||
408 | gsb->status = status; | |
409 | ||
410 | err: | |
7ef85f5f | 411 | kfree(client); |
17f4a5c4 WS |
412 | ACPI_FREE(ares); |
413 | return ret; | |
414 | } | |
415 | ||
416 | ||
417 | static int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) | |
418 | { | |
0aef44e8 | 419 | acpi_handle handle; |
17f4a5c4 WS |
420 | struct acpi_i2c_handler_data *data; |
421 | acpi_status status; | |
422 | ||
0aef44e8 PH |
423 | if (!adapter->dev.parent) |
424 | return -ENODEV; | |
425 | ||
426 | handle = ACPI_HANDLE(adapter->dev.parent); | |
427 | ||
17f4a5c4 WS |
428 | if (!handle) |
429 | return -ENODEV; | |
430 | ||
431 | data = kzalloc(sizeof(struct acpi_i2c_handler_data), | |
432 | GFP_KERNEL); | |
433 | if (!data) | |
434 | return -ENOMEM; | |
435 | ||
436 | data->adapter = adapter; | |
437 | status = acpi_bus_attach_private_data(handle, (void *)data); | |
438 | if (ACPI_FAILURE(status)) { | |
439 | kfree(data); | |
440 | return -ENOMEM; | |
441 | } | |
442 | ||
443 | status = acpi_install_address_space_handler(handle, | |
444 | ACPI_ADR_SPACE_GSBUS, | |
445 | &acpi_i2c_space_handler, | |
446 | NULL, | |
447 | data); | |
448 | if (ACPI_FAILURE(status)) { | |
449 | dev_err(&adapter->dev, "Error installing i2c space handler\n"); | |
450 | acpi_bus_detach_private_data(handle); | |
451 | kfree(data); | |
452 | return -ENOMEM; | |
453 | } | |
454 | ||
40e7fcb1 | 455 | acpi_walk_dep_device_list(handle); |
17f4a5c4 WS |
456 | return 0; |
457 | } | |
458 | ||
459 | static void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) | |
460 | { | |
0aef44e8 | 461 | acpi_handle handle; |
17f4a5c4 WS |
462 | struct acpi_i2c_handler_data *data; |
463 | acpi_status status; | |
464 | ||
0aef44e8 PH |
465 | if (!adapter->dev.parent) |
466 | return; | |
467 | ||
468 | handle = ACPI_HANDLE(adapter->dev.parent); | |
469 | ||
17f4a5c4 WS |
470 | if (!handle) |
471 | return; | |
472 | ||
473 | acpi_remove_address_space_handler(handle, | |
474 | ACPI_ADR_SPACE_GSBUS, | |
475 | &acpi_i2c_space_handler); | |
476 | ||
477 | status = acpi_bus_get_private_data(handle, (void **)&data); | |
478 | if (ACPI_SUCCESS(status)) | |
479 | kfree(data); | |
480 | ||
481 | acpi_bus_detach_private_data(handle); | |
482 | } | |
483 | #else /* CONFIG_ACPI_I2C_OPREGION */ | |
484 | static inline void acpi_i2c_remove_space_handler(struct i2c_adapter *adapter) | |
485 | { } | |
486 | ||
487 | static inline int acpi_i2c_install_space_handler(struct i2c_adapter *adapter) | |
488 | { return 0; } | |
489 | #endif /* CONFIG_ACPI_I2C_OPREGION */ | |
490 | ||
f37dd80a DB |
491 | /* ------------------------------------------------------------------------- */ |
492 | ||
d2653e92 JD |
493 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
494 | const struct i2c_client *client) | |
495 | { | |
496 | while (id->name[0]) { | |
497 | if (strcmp(client->name, id->name) == 0) | |
498 | return id; | |
499 | id++; | |
500 | } | |
501 | return NULL; | |
502 | } | |
503 | ||
1da177e4 LT |
504 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
505 | { | |
51298d12 JD |
506 | struct i2c_client *client = i2c_verify_client(dev); |
507 | struct i2c_driver *driver; | |
508 | ||
509 | if (!client) | |
510 | return 0; | |
7b4fbc50 | 511 | |
959e85f7 GL |
512 | /* Attempt an OF style match */ |
513 | if (of_driver_match_device(dev, drv)) | |
514 | return 1; | |
515 | ||
907ddf89 MW |
516 | /* Then ACPI style match */ |
517 | if (acpi_driver_match_device(dev, drv)) | |
518 | return 1; | |
519 | ||
51298d12 | 520 | driver = to_i2c_driver(drv); |
d2653e92 JD |
521 | /* match on an id table if there is one */ |
522 | if (driver->id_table) | |
523 | return i2c_match_id(driver->id_table, client) != NULL; | |
524 | ||
eb8a7908 | 525 | return 0; |
1da177e4 LT |
526 | } |
527 | ||
7b4fbc50 DB |
528 | |
529 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 530 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
531 | { |
532 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
533 | int rc; |
534 | ||
535 | rc = acpi_device_uevent_modalias(dev, env); | |
536 | if (rc != -ENODEV) | |
537 | return rc; | |
7b4fbc50 | 538 | |
eb8a7908 JD |
539 | if (add_uevent_var(env, "MODALIAS=%s%s", |
540 | I2C_MODULE_PREFIX, client->name)) | |
541 | return -ENOMEM; | |
7b4fbc50 DB |
542 | dev_dbg(dev, "uevent\n"); |
543 | return 0; | |
544 | } | |
545 | ||
5f9296ba VK |
546 | /* i2c bus recovery routines */ |
547 | static int get_scl_gpio_value(struct i2c_adapter *adap) | |
548 | { | |
549 | return gpio_get_value(adap->bus_recovery_info->scl_gpio); | |
550 | } | |
551 | ||
552 | static void set_scl_gpio_value(struct i2c_adapter *adap, int val) | |
553 | { | |
554 | gpio_set_value(adap->bus_recovery_info->scl_gpio, val); | |
555 | } | |
556 | ||
557 | static int get_sda_gpio_value(struct i2c_adapter *adap) | |
558 | { | |
559 | return gpio_get_value(adap->bus_recovery_info->sda_gpio); | |
560 | } | |
561 | ||
562 | static int i2c_get_gpios_for_recovery(struct i2c_adapter *adap) | |
563 | { | |
564 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
565 | struct device *dev = &adap->dev; | |
566 | int ret = 0; | |
567 | ||
568 | ret = gpio_request_one(bri->scl_gpio, GPIOF_OPEN_DRAIN | | |
569 | GPIOF_OUT_INIT_HIGH, "i2c-scl"); | |
570 | if (ret) { | |
571 | dev_warn(dev, "Can't get SCL gpio: %d\n", bri->scl_gpio); | |
572 | return ret; | |
573 | } | |
574 | ||
575 | if (bri->get_sda) { | |
576 | if (gpio_request_one(bri->sda_gpio, GPIOF_IN, "i2c-sda")) { | |
577 | /* work without SDA polling */ | |
578 | dev_warn(dev, "Can't get SDA gpio: %d. Not using SDA polling\n", | |
579 | bri->sda_gpio); | |
580 | bri->get_sda = NULL; | |
581 | } | |
582 | } | |
583 | ||
584 | return ret; | |
585 | } | |
586 | ||
587 | static void i2c_put_gpios_for_recovery(struct i2c_adapter *adap) | |
588 | { | |
589 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
590 | ||
591 | if (bri->get_sda) | |
592 | gpio_free(bri->sda_gpio); | |
593 | ||
594 | gpio_free(bri->scl_gpio); | |
595 | } | |
596 | ||
597 | /* | |
598 | * We are generating clock pulses. ndelay() determines durating of clk pulses. | |
599 | * We will generate clock with rate 100 KHz and so duration of both clock levels | |
600 | * is: delay in ns = (10^6 / 100) / 2 | |
601 | */ | |
602 | #define RECOVERY_NDELAY 5000 | |
603 | #define RECOVERY_CLK_CNT 9 | |
604 | ||
605 | static int i2c_generic_recovery(struct i2c_adapter *adap) | |
606 | { | |
607 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
608 | int i = 0, val = 1, ret = 0; | |
609 | ||
610 | if (bri->prepare_recovery) | |
2b2190a3 | 611 | bri->prepare_recovery(adap); |
5f9296ba | 612 | |
8b062608 JL |
613 | bri->set_scl(adap, val); |
614 | ndelay(RECOVERY_NDELAY); | |
615 | ||
5f9296ba VK |
616 | /* |
617 | * By this time SCL is high, as we need to give 9 falling-rising edges | |
618 | */ | |
619 | while (i++ < RECOVERY_CLK_CNT * 2) { | |
620 | if (val) { | |
621 | /* Break if SDA is high */ | |
622 | if (bri->get_sda && bri->get_sda(adap)) | |
623 | break; | |
624 | /* SCL shouldn't be low here */ | |
625 | if (!bri->get_scl(adap)) { | |
626 | dev_err(&adap->dev, | |
627 | "SCL is stuck low, exit recovery\n"); | |
628 | ret = -EBUSY; | |
629 | break; | |
630 | } | |
631 | } | |
632 | ||
633 | val = !val; | |
634 | bri->set_scl(adap, val); | |
635 | ndelay(RECOVERY_NDELAY); | |
636 | } | |
637 | ||
638 | if (bri->unprepare_recovery) | |
2b2190a3 | 639 | bri->unprepare_recovery(adap); |
5f9296ba VK |
640 | |
641 | return ret; | |
642 | } | |
643 | ||
644 | int i2c_generic_scl_recovery(struct i2c_adapter *adap) | |
645 | { | |
5f9296ba VK |
646 | return i2c_generic_recovery(adap); |
647 | } | |
c1c21f4e | 648 | EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); |
5f9296ba VK |
649 | |
650 | int i2c_generic_gpio_recovery(struct i2c_adapter *adap) | |
651 | { | |
652 | int ret; | |
653 | ||
654 | ret = i2c_get_gpios_for_recovery(adap); | |
655 | if (ret) | |
656 | return ret; | |
657 | ||
658 | ret = i2c_generic_recovery(adap); | |
659 | i2c_put_gpios_for_recovery(adap); | |
660 | ||
661 | return ret; | |
662 | } | |
c1c21f4e | 663 | EXPORT_SYMBOL_GPL(i2c_generic_gpio_recovery); |
5f9296ba VK |
664 | |
665 | int i2c_recover_bus(struct i2c_adapter *adap) | |
666 | { | |
667 | if (!adap->bus_recovery_info) | |
668 | return -EOPNOTSUPP; | |
669 | ||
670 | dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); | |
671 | return adap->bus_recovery_info->recover_bus(adap); | |
672 | } | |
c1c21f4e | 673 | EXPORT_SYMBOL_GPL(i2c_recover_bus); |
5f9296ba | 674 | |
f37dd80a | 675 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 676 | { |
51298d12 JD |
677 | struct i2c_client *client = i2c_verify_client(dev); |
678 | struct i2c_driver *driver; | |
50c3304a | 679 | int status; |
7b4fbc50 | 680 | |
51298d12 JD |
681 | if (!client) |
682 | return 0; | |
683 | ||
845c8770 MW |
684 | if (!client->irq) { |
685 | int irq = -ENOENT; | |
686 | ||
3fffd128 DT |
687 | if (dev->of_node) { |
688 | irq = of_irq_get_byname(dev->of_node, "irq"); | |
689 | if (irq == -EINVAL || irq == -ENODATA) | |
690 | irq = of_irq_get(dev->of_node, 0); | |
691 | } else if (ACPI_COMPANION(dev)) { | |
845c8770 | 692 | irq = acpi_dev_gpio_irq_get(ACPI_COMPANION(dev), 0); |
3fffd128 | 693 | } |
6f34be74 | 694 | if (irq == -EPROBE_DEFER) |
2fd36c55 | 695 | return irq; |
6f34be74 GU |
696 | if (irq < 0) |
697 | irq = 0; | |
2fd36c55 LP |
698 | |
699 | client->irq = irq; | |
700 | } | |
701 | ||
51298d12 | 702 | driver = to_i2c_driver(dev->driver); |
e0457442 | 703 | if (!driver->probe || !driver->id_table) |
7b4fbc50 | 704 | return -ENODEV; |
0acc2b32 | 705 | |
3fffd128 DT |
706 | if (client->flags & I2C_CLIENT_WAKE) { |
707 | int wakeirq = -ENOENT; | |
708 | ||
709 | if (dev->of_node) { | |
710 | wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); | |
711 | if (wakeirq == -EPROBE_DEFER) | |
712 | return wakeirq; | |
713 | } | |
714 | ||
715 | device_init_wakeup(&client->dev, true); | |
716 | ||
717 | if (wakeirq > 0 && wakeirq != client->irq) | |
718 | status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); | |
719 | else if (client->irq > 0) | |
c18fba23 | 720 | status = dev_pm_set_wake_irq(dev, client->irq); |
3fffd128 DT |
721 | else |
722 | status = 0; | |
723 | ||
724 | if (status) | |
725 | dev_warn(&client->dev, "failed to set up wakeup irq"); | |
726 | } | |
727 | ||
7b4fbc50 | 728 | dev_dbg(dev, "probe\n"); |
d2653e92 | 729 | |
86be408b SN |
730 | status = of_clk_set_defaults(dev->of_node, false); |
731 | if (status < 0) | |
3fffd128 | 732 | goto err_clear_wakeup_irq; |
86be408b | 733 | |
e09b0d4e | 734 | status = dev_pm_domain_attach(&client->dev, true); |
74cedd30 KB |
735 | if (status == -EPROBE_DEFER) |
736 | goto err_clear_wakeup_irq; | |
737 | ||
738 | status = driver->probe(client, i2c_match_id(driver->id_table, client)); | |
739 | if (status) | |
740 | goto err_detach_pm_domain; | |
72fa818e | 741 | |
3fffd128 DT |
742 | return 0; |
743 | ||
744 | err_detach_pm_domain: | |
745 | dev_pm_domain_detach(&client->dev, true); | |
746 | err_clear_wakeup_irq: | |
747 | dev_pm_clear_wake_irq(&client->dev); | |
748 | device_init_wakeup(&client->dev, false); | |
50c3304a | 749 | return status; |
f37dd80a | 750 | } |
1da177e4 | 751 | |
f37dd80a DB |
752 | static int i2c_device_remove(struct device *dev) |
753 | { | |
51298d12 | 754 | struct i2c_client *client = i2c_verify_client(dev); |
a1d9e6e4 | 755 | struct i2c_driver *driver; |
72fa818e | 756 | int status = 0; |
a1d9e6e4 | 757 | |
51298d12 | 758 | if (!client || !dev->driver) |
a1d9e6e4 DB |
759 | return 0; |
760 | ||
761 | driver = to_i2c_driver(dev->driver); | |
762 | if (driver->remove) { | |
763 | dev_dbg(dev, "remove\n"); | |
764 | status = driver->remove(client); | |
a1d9e6e4 | 765 | } |
72fa818e | 766 | |
e09b0d4e | 767 | dev_pm_domain_detach(&client->dev, true); |
3fffd128 DT |
768 | |
769 | dev_pm_clear_wake_irq(&client->dev); | |
770 | device_init_wakeup(&client->dev, false); | |
771 | ||
a1d9e6e4 | 772 | return status; |
1da177e4 LT |
773 | } |
774 | ||
f37dd80a | 775 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 776 | { |
51298d12 | 777 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
778 | struct i2c_driver *driver; |
779 | ||
51298d12 | 780 | if (!client || !dev->driver) |
f37dd80a DB |
781 | return; |
782 | driver = to_i2c_driver(dev->driver); | |
783 | if (driver->shutdown) | |
51298d12 | 784 | driver->shutdown(client); |
1da177e4 LT |
785 | } |
786 | ||
9c1600ed DB |
787 | static void i2c_client_dev_release(struct device *dev) |
788 | { | |
789 | kfree(to_i2c_client(dev)); | |
790 | } | |
791 | ||
09b8ce0a | 792 | static ssize_t |
4f8cf824 | 793 | show_name(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 794 | { |
4f8cf824 JD |
795 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
796 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 | 797 | } |
a5eb71b2 | 798 | static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); |
7b4fbc50 | 799 | |
09b8ce0a ZX |
800 | static ssize_t |
801 | show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
7b4fbc50 DB |
802 | { |
803 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
804 | int len; |
805 | ||
806 | len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); | |
807 | if (len != -ENODEV) | |
808 | return len; | |
809 | ||
eb8a7908 | 810 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 | 811 | } |
51298d12 JD |
812 | static DEVICE_ATTR(modalias, S_IRUGO, show_modalias, NULL); |
813 | ||
814 | static struct attribute *i2c_dev_attrs[] = { | |
815 | &dev_attr_name.attr, | |
7b4fbc50 | 816 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
817 | &dev_attr_modalias.attr, |
818 | NULL | |
819 | }; | |
a5eb71b2 | 820 | ATTRIBUTE_GROUPS(i2c_dev); |
54067ee2 | 821 | |
e9ca9eb9 | 822 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
823 | .name = "i2c", |
824 | .match = i2c_device_match, | |
825 | .probe = i2c_device_probe, | |
826 | .remove = i2c_device_remove, | |
827 | .shutdown = i2c_device_shutdown, | |
b864c7d5 | 828 | }; |
e9ca9eb9 | 829 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 830 | |
51298d12 | 831 | static struct device_type i2c_client_type = { |
a5eb71b2 | 832 | .groups = i2c_dev_groups, |
51298d12 JD |
833 | .uevent = i2c_device_uevent, |
834 | .release = i2c_client_dev_release, | |
835 | }; | |
836 | ||
9b766b81 DB |
837 | |
838 | /** | |
839 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
840 | * @dev: device, probably from some driver model iterator | |
841 | * | |
842 | * When traversing the driver model tree, perhaps using driver model | |
843 | * iterators like @device_for_each_child(), you can't assume very much | |
844 | * about the nodes you find. Use this function to avoid oopses caused | |
845 | * by wrongly treating some non-I2C device as an i2c_client. | |
846 | */ | |
847 | struct i2c_client *i2c_verify_client(struct device *dev) | |
848 | { | |
51298d12 | 849 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
850 | ? to_i2c_client(dev) |
851 | : NULL; | |
852 | } | |
853 | EXPORT_SYMBOL(i2c_verify_client); | |
854 | ||
855 | ||
da899f55 WS |
856 | /* Return a unique address which takes the flags of the client into account */ |
857 | static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) | |
858 | { | |
859 | unsigned short addr = client->addr; | |
860 | ||
861 | /* For some client flags, add an arbitrary offset to avoid collisions */ | |
862 | if (client->flags & I2C_CLIENT_TEN) | |
863 | addr |= I2C_ADDR_OFFSET_TEN_BIT; | |
864 | ||
865 | if (client->flags & I2C_CLIENT_SLAVE) | |
866 | addr |= I2C_ADDR_OFFSET_SLAVE; | |
867 | ||
868 | return addr; | |
869 | } | |
870 | ||
3a89db5f | 871 | /* This is a permissive address validity check, I2C address map constraints |
25985edc | 872 | * are purposely not enforced, except for the general call address. */ |
c4019b70 | 873 | static int i2c_check_addr_validity(unsigned addr, unsigned short flags) |
3a89db5f | 874 | { |
c4019b70 | 875 | if (flags & I2C_CLIENT_TEN) { |
3a89db5f | 876 | /* 10-bit address, all values are valid */ |
c4019b70 | 877 | if (addr > 0x3ff) |
3a89db5f JD |
878 | return -EINVAL; |
879 | } else { | |
880 | /* 7-bit address, reject the general call address */ | |
c4019b70 | 881 | if (addr == 0x00 || addr > 0x7f) |
3a89db5f JD |
882 | return -EINVAL; |
883 | } | |
884 | return 0; | |
885 | } | |
886 | ||
656b8761 JD |
887 | /* And this is a strict address validity check, used when probing. If a |
888 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
889 | * addressing is assumed, 10-bit address devices are rare and should be | |
890 | * explicitly enumerated. */ | |
66be6056 | 891 | static int i2c_check_7bit_addr_validity_strict(unsigned short addr) |
656b8761 JD |
892 | { |
893 | /* | |
894 | * Reserved addresses per I2C specification: | |
895 | * 0x00 General call address / START byte | |
896 | * 0x01 CBUS address | |
897 | * 0x02 Reserved for different bus format | |
898 | * 0x03 Reserved for future purposes | |
899 | * 0x04-0x07 Hs-mode master code | |
900 | * 0x78-0x7b 10-bit slave addressing | |
901 | * 0x7c-0x7f Reserved for future purposes | |
902 | */ | |
903 | if (addr < 0x08 || addr > 0x77) | |
904 | return -EINVAL; | |
905 | return 0; | |
906 | } | |
907 | ||
3b5f794b JD |
908 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
909 | { | |
910 | struct i2c_client *client = i2c_verify_client(dev); | |
911 | int addr = *(int *)addrp; | |
912 | ||
9bccc70a | 913 | if (client && i2c_encode_flags_to_addr(client) == addr) |
3b5f794b JD |
914 | return -EBUSY; |
915 | return 0; | |
916 | } | |
917 | ||
0826374b ML |
918 | /* walk up mux tree */ |
919 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
920 | { | |
97cc4d49 | 921 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
922 | int result; |
923 | ||
924 | result = device_for_each_child(&adapter->dev, &addr, | |
925 | __i2c_check_addr_busy); | |
926 | ||
97cc4d49 JD |
927 | if (!result && parent) |
928 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
929 | |
930 | return result; | |
931 | } | |
932 | ||
933 | /* recurse down mux tree */ | |
934 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
935 | { | |
936 | int result; | |
937 | ||
938 | if (dev->type == &i2c_adapter_type) | |
939 | result = device_for_each_child(dev, addrp, | |
940 | i2c_check_mux_children); | |
941 | else | |
942 | result = __i2c_check_addr_busy(dev, addrp); | |
943 | ||
944 | return result; | |
945 | } | |
946 | ||
3b5f794b JD |
947 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
948 | { | |
97cc4d49 | 949 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
950 | int result = 0; |
951 | ||
97cc4d49 JD |
952 | if (parent) |
953 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
954 | |
955 | if (!result) | |
956 | result = device_for_each_child(&adapter->dev, &addr, | |
957 | i2c_check_mux_children); | |
958 | ||
959 | return result; | |
3b5f794b JD |
960 | } |
961 | ||
fe61e07e JD |
962 | /** |
963 | * i2c_lock_adapter - Get exclusive access to an I2C bus segment | |
964 | * @adapter: Target I2C bus segment | |
965 | */ | |
966 | void i2c_lock_adapter(struct i2c_adapter *adapter) | |
967 | { | |
97cc4d49 JD |
968 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
969 | ||
970 | if (parent) | |
971 | i2c_lock_adapter(parent); | |
0826374b ML |
972 | else |
973 | rt_mutex_lock(&adapter->bus_lock); | |
fe61e07e JD |
974 | } |
975 | EXPORT_SYMBOL_GPL(i2c_lock_adapter); | |
976 | ||
977 | /** | |
978 | * i2c_trylock_adapter - Try to get exclusive access to an I2C bus segment | |
979 | * @adapter: Target I2C bus segment | |
980 | */ | |
981 | static int i2c_trylock_adapter(struct i2c_adapter *adapter) | |
982 | { | |
97cc4d49 JD |
983 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
984 | ||
985 | if (parent) | |
986 | return i2c_trylock_adapter(parent); | |
0826374b ML |
987 | else |
988 | return rt_mutex_trylock(&adapter->bus_lock); | |
fe61e07e JD |
989 | } |
990 | ||
991 | /** | |
992 | * i2c_unlock_adapter - Release exclusive access to an I2C bus segment | |
993 | * @adapter: Target I2C bus segment | |
994 | */ | |
995 | void i2c_unlock_adapter(struct i2c_adapter *adapter) | |
996 | { | |
97cc4d49 JD |
997 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
998 | ||
999 | if (parent) | |
1000 | i2c_unlock_adapter(parent); | |
0826374b ML |
1001 | else |
1002 | rt_mutex_unlock(&adapter->bus_lock); | |
fe61e07e JD |
1003 | } |
1004 | EXPORT_SYMBOL_GPL(i2c_unlock_adapter); | |
1005 | ||
70762abb JN |
1006 | static void i2c_dev_set_name(struct i2c_adapter *adap, |
1007 | struct i2c_client *client) | |
1008 | { | |
1009 | struct acpi_device *adev = ACPI_COMPANION(&client->dev); | |
1010 | ||
1011 | if (adev) { | |
1012 | dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); | |
1013 | return; | |
1014 | } | |
1015 | ||
70762abb | 1016 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), |
da899f55 | 1017 | i2c_encode_flags_to_addr(client)); |
70762abb JN |
1018 | } |
1019 | ||
9c1600ed | 1020 | /** |
f8a227e8 | 1021 | * i2c_new_device - instantiate an i2c device |
9c1600ed DB |
1022 | * @adap: the adapter managing the device |
1023 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 1024 | * Context: can sleep |
9c1600ed | 1025 | * |
f8a227e8 JD |
1026 | * Create an i2c device. Binding is handled through driver model |
1027 | * probe()/remove() methods. A driver may be bound to this device when we | |
1028 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
1029 | * load the driver module). This call is not appropriate for use by mainboard | |
1030 | * initialization logic, which usually runs during an arch_initcall() long | |
1031 | * before any i2c_adapter could exist. | |
9c1600ed DB |
1032 | * |
1033 | * This returns the new i2c client, which may be saved for later use with | |
1034 | * i2c_unregister_device(); or NULL to indicate an error. | |
1035 | */ | |
1036 | struct i2c_client * | |
1037 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
1038 | { | |
1039 | struct i2c_client *client; | |
1040 | int status; | |
1041 | ||
1042 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
1043 | if (!client) | |
1044 | return NULL; | |
1045 | ||
1046 | client->adapter = adap; | |
1047 | ||
1048 | client->dev.platform_data = info->platform_data; | |
3bbb835d | 1049 | |
11f1f2af AV |
1050 | if (info->archdata) |
1051 | client->dev.archdata = *info->archdata; | |
1052 | ||
ee35425c | 1053 | client->flags = info->flags; |
9c1600ed DB |
1054 | client->addr = info->addr; |
1055 | client->irq = info->irq; | |
1056 | ||
9c1600ed DB |
1057 | strlcpy(client->name, info->type, sizeof(client->name)); |
1058 | ||
c4019b70 | 1059 | status = i2c_check_addr_validity(client->addr, client->flags); |
3a89db5f JD |
1060 | if (status) { |
1061 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
1062 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
1063 | goto out_err_silent; | |
1064 | } | |
1065 | ||
f8a227e8 | 1066 | /* Check for address business */ |
9bccc70a | 1067 | status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); |
f8a227e8 JD |
1068 | if (status) |
1069 | goto out_err; | |
1070 | ||
1071 | client->dev.parent = &client->adapter->dev; | |
1072 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 1073 | client->dev.type = &i2c_client_type; |
d12d42f7 | 1074 | client->dev.of_node = info->of_node; |
ce793486 | 1075 | client->dev.fwnode = info->fwnode; |
f8a227e8 | 1076 | |
70762abb | 1077 | i2c_dev_set_name(adap, client); |
f8a227e8 JD |
1078 | status = device_register(&client->dev); |
1079 | if (status) | |
1080 | goto out_err; | |
1081 | ||
f8a227e8 JD |
1082 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
1083 | client->name, dev_name(&client->dev)); | |
1084 | ||
9c1600ed | 1085 | return client; |
f8a227e8 JD |
1086 | |
1087 | out_err: | |
1088 | dev_err(&adap->dev, "Failed to register i2c client %s at 0x%02x " | |
1089 | "(%d)\n", client->name, client->addr, status); | |
3a89db5f | 1090 | out_err_silent: |
f8a227e8 JD |
1091 | kfree(client); |
1092 | return NULL; | |
9c1600ed DB |
1093 | } |
1094 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
1095 | ||
1096 | ||
1097 | /** | |
1098 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
1099 | * @client: value returned from i2c_new_device() | |
d64f73be | 1100 | * Context: can sleep |
9c1600ed DB |
1101 | */ |
1102 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 1103 | { |
4f001fd3 PA |
1104 | if (client->dev.of_node) |
1105 | of_node_clear_flag(client->dev.of_node, OF_POPULATED); | |
a1d9e6e4 DB |
1106 | device_unregister(&client->dev); |
1107 | } | |
9c1600ed | 1108 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
1109 | |
1110 | ||
60b129d7 JD |
1111 | static const struct i2c_device_id dummy_id[] = { |
1112 | { "dummy", 0 }, | |
1113 | { }, | |
1114 | }; | |
1115 | ||
d2653e92 JD |
1116 | static int dummy_probe(struct i2c_client *client, |
1117 | const struct i2c_device_id *id) | |
1118 | { | |
1119 | return 0; | |
1120 | } | |
1121 | ||
1122 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
1123 | { |
1124 | return 0; | |
1125 | } | |
1126 | ||
1127 | static struct i2c_driver dummy_driver = { | |
1128 | .driver.name = "dummy", | |
d2653e92 JD |
1129 | .probe = dummy_probe, |
1130 | .remove = dummy_remove, | |
60b129d7 | 1131 | .id_table = dummy_id, |
e9f1373b DB |
1132 | }; |
1133 | ||
1134 | /** | |
1135 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
1136 | * @adapter: the adapter managing the device | |
1137 | * @address: seven bit address to be used | |
e9f1373b DB |
1138 | * Context: can sleep |
1139 | * | |
1140 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
1141 | * with devices that consume multiple addresses. Examples of such chips | |
1142 | * include various EEPROMS (like 24c04 and 24c08 models). | |
1143 | * | |
1144 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
1145 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
1146 | * And second, this prevents the specified address from being bound to a | |
1147 | * different driver. | |
1148 | * | |
1149 | * This returns the new i2c client, which should be saved for later use with | |
1150 | * i2c_unregister_device(); or NULL to indicate an error. | |
1151 | */ | |
09b8ce0a | 1152 | struct i2c_client *i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
1153 | { |
1154 | struct i2c_board_info info = { | |
60b129d7 | 1155 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
1156 | }; |
1157 | ||
e9f1373b DB |
1158 | return i2c_new_device(adapter, &info); |
1159 | } | |
1160 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
1161 | ||
f37dd80a DB |
1162 | /* ------------------------------------------------------------------------- */ |
1163 | ||
16ffadfc DB |
1164 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
1165 | ||
83eaaed0 | 1166 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 1167 | { |
ef2c8321 | 1168 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
1169 | complete(&adap->dev_released); |
1170 | } | |
1171 | ||
390946b1 JD |
1172 | /* |
1173 | * This function is only needed for mutex_lock_nested, so it is never | |
1174 | * called unless locking correctness checking is enabled. Thus we | |
1175 | * make it inline to avoid a compiler warning. That's what gcc ends up | |
1176 | * doing anyway. | |
1177 | */ | |
1178 | static inline unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) | |
1179 | { | |
1180 | unsigned int depth = 0; | |
1181 | ||
1182 | while ((adapter = i2c_parent_is_i2c_adapter(adapter))) | |
1183 | depth++; | |
1184 | ||
1185 | return depth; | |
1186 | } | |
1187 | ||
99cd8e25 JD |
1188 | /* |
1189 | * Let users instantiate I2C devices through sysfs. This can be used when | |
1190 | * platform initialization code doesn't contain the proper data for | |
1191 | * whatever reason. Also useful for drivers that do device detection and | |
1192 | * detection fails, either because the device uses an unexpected address, | |
1193 | * or this is a compatible device with different ID register values. | |
1194 | * | |
1195 | * Parameter checking may look overzealous, but we really don't want | |
1196 | * the user to provide incorrect parameters. | |
1197 | */ | |
1198 | static ssize_t | |
1199 | i2c_sysfs_new_device(struct device *dev, struct device_attribute *attr, | |
1200 | const char *buf, size_t count) | |
1201 | { | |
1202 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1203 | struct i2c_board_info info; | |
1204 | struct i2c_client *client; | |
1205 | char *blank, end; | |
1206 | int res; | |
1207 | ||
99cd8e25 JD |
1208 | memset(&info, 0, sizeof(struct i2c_board_info)); |
1209 | ||
1210 | blank = strchr(buf, ' '); | |
1211 | if (!blank) { | |
1212 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
1213 | return -EINVAL; | |
1214 | } | |
1215 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
1216 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
1217 | return -EINVAL; | |
1218 | } | |
1219 | memcpy(info.type, buf, blank - buf); | |
1220 | ||
1221 | /* Parse remaining parameters, reject extra parameters */ | |
1222 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
1223 | if (res < 1) { | |
1224 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
1225 | return -EINVAL; | |
1226 | } | |
1227 | if (res > 1 && end != '\n') { | |
1228 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
1229 | return -EINVAL; | |
1230 | } | |
1231 | ||
cfa0327b WS |
1232 | if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { |
1233 | info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; | |
1234 | info.flags |= I2C_CLIENT_TEN; | |
1235 | } | |
1236 | ||
1237 | if (info.addr & I2C_ADDR_OFFSET_SLAVE) { | |
1238 | info.addr &= ~I2C_ADDR_OFFSET_SLAVE; | |
1239 | info.flags |= I2C_CLIENT_SLAVE; | |
1240 | } | |
1241 | ||
99cd8e25 JD |
1242 | client = i2c_new_device(adap, &info); |
1243 | if (!client) | |
3a89db5f | 1244 | return -EINVAL; |
99cd8e25 JD |
1245 | |
1246 | /* Keep track of the added device */ | |
dafc50d1 | 1247 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 1248 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 1249 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1250 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
1251 | info.type, info.addr); | |
1252 | ||
1253 | return count; | |
1254 | } | |
a5eb71b2 | 1255 | static DEVICE_ATTR(new_device, S_IWUSR, NULL, i2c_sysfs_new_device); |
99cd8e25 JD |
1256 | |
1257 | /* | |
1258 | * And of course let the users delete the devices they instantiated, if | |
1259 | * they got it wrong. This interface can only be used to delete devices | |
1260 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
1261 | * don't delete devices to which some kernel code still has references. | |
1262 | * | |
1263 | * Parameter checking may look overzealous, but we really don't want | |
1264 | * the user to delete the wrong device. | |
1265 | */ | |
1266 | static ssize_t | |
1267 | i2c_sysfs_delete_device(struct device *dev, struct device_attribute *attr, | |
1268 | const char *buf, size_t count) | |
1269 | { | |
1270 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1271 | struct i2c_client *client, *next; | |
1272 | unsigned short addr; | |
1273 | char end; | |
1274 | int res; | |
1275 | ||
1276 | /* Parse parameters, reject extra parameters */ | |
1277 | res = sscanf(buf, "%hi%c", &addr, &end); | |
1278 | if (res < 1) { | |
1279 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
1280 | return -EINVAL; | |
1281 | } | |
1282 | if (res > 1 && end != '\n') { | |
1283 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
1284 | return -EINVAL; | |
1285 | } | |
1286 | ||
1287 | /* Make sure the device was added through sysfs */ | |
1288 | res = -ENOENT; | |
390946b1 JD |
1289 | mutex_lock_nested(&adap->userspace_clients_lock, |
1290 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1291 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1292 | detected) { | |
cfa0327b | 1293 | if (i2c_encode_flags_to_addr(client) == addr) { |
99cd8e25 JD |
1294 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
1295 | "delete_device", client->name, client->addr); | |
1296 | ||
1297 | list_del(&client->detected); | |
1298 | i2c_unregister_device(client); | |
1299 | res = count; | |
1300 | break; | |
1301 | } | |
1302 | } | |
dafc50d1 | 1303 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1304 | |
1305 | if (res < 0) | |
1306 | dev_err(dev, "%s: Can't find device in list\n", | |
1307 | "delete_device"); | |
1308 | return res; | |
1309 | } | |
e9b526fe AS |
1310 | static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, |
1311 | i2c_sysfs_delete_device); | |
4f8cf824 JD |
1312 | |
1313 | static struct attribute *i2c_adapter_attrs[] = { | |
1314 | &dev_attr_name.attr, | |
1315 | &dev_attr_new_device.attr, | |
1316 | &dev_attr_delete_device.attr, | |
1317 | NULL | |
1318 | }; | |
a5eb71b2 | 1319 | ATTRIBUTE_GROUPS(i2c_adapter); |
b119dc3f | 1320 | |
0826374b | 1321 | struct device_type i2c_adapter_type = { |
a5eb71b2 | 1322 | .groups = i2c_adapter_groups, |
4f8cf824 | 1323 | .release = i2c_adapter_dev_release, |
1da177e4 | 1324 | }; |
0826374b | 1325 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 1326 | |
643dd09e SW |
1327 | /** |
1328 | * i2c_verify_adapter - return parameter as i2c_adapter or NULL | |
1329 | * @dev: device, probably from some driver model iterator | |
1330 | * | |
1331 | * When traversing the driver model tree, perhaps using driver model | |
1332 | * iterators like @device_for_each_child(), you can't assume very much | |
1333 | * about the nodes you find. Use this function to avoid oopses caused | |
1334 | * by wrongly treating some non-I2C device as an i2c_adapter. | |
1335 | */ | |
1336 | struct i2c_adapter *i2c_verify_adapter(struct device *dev) | |
1337 | { | |
1338 | return (dev->type == &i2c_adapter_type) | |
1339 | ? to_i2c_adapter(dev) | |
1340 | : NULL; | |
1341 | } | |
1342 | EXPORT_SYMBOL(i2c_verify_adapter); | |
1343 | ||
2bb5095a JD |
1344 | #ifdef CONFIG_I2C_COMPAT |
1345 | static struct class_compat *i2c_adapter_compat_class; | |
1346 | #endif | |
1347 | ||
9c1600ed DB |
1348 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
1349 | { | |
1350 | struct i2c_devinfo *devinfo; | |
1351 | ||
f18c41da | 1352 | down_read(&__i2c_board_lock); |
9c1600ed DB |
1353 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
1354 | if (devinfo->busnum == adapter->nr | |
1355 | && !i2c_new_device(adapter, | |
1356 | &devinfo->board_info)) | |
09b8ce0a ZX |
1357 | dev_err(&adapter->dev, |
1358 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
1359 | devinfo->board_info.addr); |
1360 | } | |
f18c41da | 1361 | up_read(&__i2c_board_lock); |
9c1600ed DB |
1362 | } |
1363 | ||
687b81d0 WS |
1364 | /* OF support code */ |
1365 | ||
1366 | #if IS_ENABLED(CONFIG_OF) | |
a430a345 PA |
1367 | static struct i2c_client *of_i2c_register_device(struct i2c_adapter *adap, |
1368 | struct device_node *node) | |
687b81d0 | 1369 | { |
a430a345 PA |
1370 | struct i2c_client *result; |
1371 | struct i2c_board_info info = {}; | |
1372 | struct dev_archdata dev_ad = {}; | |
b4e2f6ac WS |
1373 | const __be32 *addr_be; |
1374 | u32 addr; | |
a430a345 | 1375 | int len; |
687b81d0 | 1376 | |
a430a345 | 1377 | dev_dbg(&adap->dev, "of_i2c: register %s\n", node->full_name); |
687b81d0 | 1378 | |
a430a345 PA |
1379 | if (of_modalias_node(node, info.type, sizeof(info.type)) < 0) { |
1380 | dev_err(&adap->dev, "of_i2c: modalias failure on %s\n", | |
1381 | node->full_name); | |
1382 | return ERR_PTR(-EINVAL); | |
1383 | } | |
687b81d0 | 1384 | |
b4e2f6ac WS |
1385 | addr_be = of_get_property(node, "reg", &len); |
1386 | if (!addr_be || (len < sizeof(*addr_be))) { | |
a430a345 PA |
1387 | dev_err(&adap->dev, "of_i2c: invalid reg on %s\n", |
1388 | node->full_name); | |
1389 | return ERR_PTR(-EINVAL); | |
1390 | } | |
687b81d0 | 1391 | |
b4e2f6ac WS |
1392 | addr = be32_to_cpup(addr_be); |
1393 | if (addr & I2C_TEN_BIT_ADDRESS) { | |
1394 | addr &= ~I2C_TEN_BIT_ADDRESS; | |
1395 | info.flags |= I2C_CLIENT_TEN; | |
1396 | } | |
1397 | ||
1398 | if (addr & I2C_OWN_SLAVE_ADDRESS) { | |
1399 | addr &= ~I2C_OWN_SLAVE_ADDRESS; | |
1400 | info.flags |= I2C_CLIENT_SLAVE; | |
1401 | } | |
1402 | ||
1403 | if (i2c_check_addr_validity(addr, info.flags)) { | |
a430a345 PA |
1404 | dev_err(&adap->dev, "of_i2c: invalid addr=%x on %s\n", |
1405 | info.addr, node->full_name); | |
1406 | return ERR_PTR(-EINVAL); | |
1407 | } | |
687b81d0 | 1408 | |
b4e2f6ac | 1409 | info.addr = addr; |
a430a345 PA |
1410 | info.of_node = of_node_get(node); |
1411 | info.archdata = &dev_ad; | |
687b81d0 | 1412 | |
a430a345 PA |
1413 | if (of_get_property(node, "wakeup-source", NULL)) |
1414 | info.flags |= I2C_CLIENT_WAKE; | |
687b81d0 | 1415 | |
a430a345 PA |
1416 | result = i2c_new_device(adap, &info); |
1417 | if (result == NULL) { | |
1418 | dev_err(&adap->dev, "of_i2c: Failure registering %s\n", | |
1419 | node->full_name); | |
1420 | of_node_put(node); | |
a430a345 PA |
1421 | return ERR_PTR(-EINVAL); |
1422 | } | |
1423 | return result; | |
1424 | } | |
687b81d0 | 1425 | |
a430a345 PA |
1426 | static void of_i2c_register_devices(struct i2c_adapter *adap) |
1427 | { | |
1428 | struct device_node *node; | |
687b81d0 | 1429 | |
a430a345 PA |
1430 | /* Only register child devices if the adapter has a node pointer set */ |
1431 | if (!adap->dev.of_node) | |
1432 | return; | |
687b81d0 | 1433 | |
a430a345 PA |
1434 | dev_dbg(&adap->dev, "of_i2c: walking child nodes\n"); |
1435 | ||
4f001fd3 PA |
1436 | for_each_available_child_of_node(adap->dev.of_node, node) { |
1437 | if (of_node_test_and_set_flag(node, OF_POPULATED)) | |
1438 | continue; | |
a430a345 | 1439 | of_i2c_register_device(adap, node); |
4f001fd3 | 1440 | } |
687b81d0 WS |
1441 | } |
1442 | ||
1443 | static int of_dev_node_match(struct device *dev, void *data) | |
1444 | { | |
1445 | return dev->of_node == data; | |
1446 | } | |
1447 | ||
1448 | /* must call put_device() when done with returned i2c_client device */ | |
1449 | struct i2c_client *of_find_i2c_device_by_node(struct device_node *node) | |
1450 | { | |
1451 | struct device *dev; | |
e3311469 | 1452 | struct i2c_client *client; |
687b81d0 | 1453 | |
e3311469 | 1454 | dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match); |
687b81d0 WS |
1455 | if (!dev) |
1456 | return NULL; | |
1457 | ||
e3311469 VZ |
1458 | client = i2c_verify_client(dev); |
1459 | if (!client) | |
1460 | put_device(dev); | |
1461 | ||
1462 | return client; | |
687b81d0 WS |
1463 | } |
1464 | EXPORT_SYMBOL(of_find_i2c_device_by_node); | |
1465 | ||
1466 | /* must call put_device() when done with returned i2c_adapter device */ | |
1467 | struct i2c_adapter *of_find_i2c_adapter_by_node(struct device_node *node) | |
1468 | { | |
1469 | struct device *dev; | |
e3311469 | 1470 | struct i2c_adapter *adapter; |
687b81d0 | 1471 | |
e3311469 | 1472 | dev = bus_find_device(&i2c_bus_type, NULL, node, of_dev_node_match); |
687b81d0 WS |
1473 | if (!dev) |
1474 | return NULL; | |
1475 | ||
e3311469 VZ |
1476 | adapter = i2c_verify_adapter(dev); |
1477 | if (!adapter) | |
1478 | put_device(dev); | |
1479 | ||
1480 | return adapter; | |
687b81d0 WS |
1481 | } |
1482 | EXPORT_SYMBOL(of_find_i2c_adapter_by_node); | |
48e9743d VZ |
1483 | |
1484 | /* must call i2c_put_adapter() when done with returned i2c_adapter device */ | |
1485 | struct i2c_adapter *of_get_i2c_adapter_by_node(struct device_node *node) | |
1486 | { | |
1487 | struct i2c_adapter *adapter; | |
1488 | ||
1489 | adapter = of_find_i2c_adapter_by_node(node); | |
1490 | if (!adapter) | |
1491 | return NULL; | |
1492 | ||
1493 | if (!try_module_get(adapter->owner)) { | |
1494 | put_device(&adapter->dev); | |
1495 | adapter = NULL; | |
1496 | } | |
1497 | ||
1498 | return adapter; | |
1499 | } | |
1500 | EXPORT_SYMBOL(of_get_i2c_adapter_by_node); | |
687b81d0 WS |
1501 | #else |
1502 | static void of_i2c_register_devices(struct i2c_adapter *adap) { } | |
1503 | #endif /* CONFIG_OF */ | |
1504 | ||
69b0089a JD |
1505 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
1506 | struct i2c_adapter *adap) | |
026526f5 | 1507 | { |
4735c98f JD |
1508 | /* Detect supported devices on that bus, and instantiate them */ |
1509 | i2c_detect(adap, driver); | |
1510 | ||
1511 | /* Let legacy drivers scan this bus for matching devices */ | |
026526f5 | 1512 | if (driver->attach_adapter) { |
a920ff41 JD |
1513 | dev_warn(&adap->dev, "%s: attach_adapter method is deprecated\n", |
1514 | driver->driver.name); | |
fe6fc258 JD |
1515 | dev_warn(&adap->dev, "Please use another way to instantiate " |
1516 | "your i2c_client\n"); | |
026526f5 JD |
1517 | /* We ignore the return code; if it fails, too bad */ |
1518 | driver->attach_adapter(adap); | |
1519 | } | |
1520 | return 0; | |
1521 | } | |
1522 | ||
69b0089a JD |
1523 | static int __process_new_adapter(struct device_driver *d, void *data) |
1524 | { | |
1525 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
1526 | } | |
1527 | ||
6e13e641 | 1528 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 1529 | { |
d6703281 | 1530 | int res = 0; |
1da177e4 | 1531 | |
1d0b19c9 | 1532 | /* Can't register until after driver model init */ |
95026658 | 1533 | if (WARN_ON(!is_registered)) { |
35fc37f8 JD |
1534 | res = -EAGAIN; |
1535 | goto out_list; | |
1536 | } | |
1d0b19c9 | 1537 | |
2236baa7 JD |
1538 | /* Sanity checks */ |
1539 | if (unlikely(adap->name[0] == '\0')) { | |
1540 | pr_err("i2c-core: Attempt to register an adapter with " | |
1541 | "no name!\n"); | |
1542 | return -EINVAL; | |
1543 | } | |
1544 | if (unlikely(!adap->algo)) { | |
1545 | pr_err("i2c-core: Attempt to register adapter '%s' with " | |
1546 | "no algo!\n", adap->name); | |
1547 | return -EINVAL; | |
1548 | } | |
1549 | ||
194684e5 | 1550 | rt_mutex_init(&adap->bus_lock); |
dafc50d1 | 1551 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 1552 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 1553 | |
8fcfef6e JD |
1554 | /* Set default timeout to 1 second if not already set */ |
1555 | if (adap->timeout == 0) | |
1556 | adap->timeout = HZ; | |
1557 | ||
27d9c183 | 1558 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
1559 | adap->dev.bus = &i2c_bus_type; |
1560 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 JD |
1561 | res = device_register(&adap->dev); |
1562 | if (res) | |
1563 | goto out_list; | |
1da177e4 | 1564 | |
b6d7b3d1 JD |
1565 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
1566 | ||
6ada5c1e | 1567 | pm_runtime_no_callbacks(&adap->dev); |
9f924169 | 1568 | pm_runtime_enable(&adap->dev); |
6ada5c1e | 1569 | |
2bb5095a JD |
1570 | #ifdef CONFIG_I2C_COMPAT |
1571 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
1572 | adap->dev.parent); | |
1573 | if (res) | |
1574 | dev_warn(&adap->dev, | |
1575 | "Failed to create compatibility class link\n"); | |
1576 | #endif | |
1577 | ||
5f9296ba VK |
1578 | /* bus recovery specific initialization */ |
1579 | if (adap->bus_recovery_info) { | |
1580 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
1581 | ||
1582 | if (!bri->recover_bus) { | |
1583 | dev_err(&adap->dev, "No recover_bus() found, not using recovery\n"); | |
1584 | adap->bus_recovery_info = NULL; | |
1585 | goto exit_recovery; | |
1586 | } | |
1587 | ||
1588 | /* Generic GPIO recovery */ | |
1589 | if (bri->recover_bus == i2c_generic_gpio_recovery) { | |
1590 | if (!gpio_is_valid(bri->scl_gpio)) { | |
1591 | dev_err(&adap->dev, "Invalid SCL gpio, not using recovery\n"); | |
1592 | adap->bus_recovery_info = NULL; | |
1593 | goto exit_recovery; | |
1594 | } | |
1595 | ||
1596 | if (gpio_is_valid(bri->sda_gpio)) | |
1597 | bri->get_sda = get_sda_gpio_value; | |
1598 | else | |
1599 | bri->get_sda = NULL; | |
1600 | ||
1601 | bri->get_scl = get_scl_gpio_value; | |
1602 | bri->set_scl = set_scl_gpio_value; | |
1603 | } else if (!bri->set_scl || !bri->get_scl) { | |
1604 | /* Generic SCL recovery */ | |
1605 | dev_err(&adap->dev, "No {get|set}_gpio() found, not using recovery\n"); | |
1606 | adap->bus_recovery_info = NULL; | |
1607 | } | |
1608 | } | |
1609 | ||
1610 | exit_recovery: | |
729d6dd5 | 1611 | /* create pre-declared device nodes */ |
687b81d0 | 1612 | of_i2c_register_devices(adap); |
55e71edb | 1613 | acpi_i2c_register_devices(adap); |
5d98e61d | 1614 | acpi_i2c_install_space_handler(adap); |
687b81d0 | 1615 | |
6e13e641 DB |
1616 | if (adap->nr < __i2c_first_dynamic_bus_num) |
1617 | i2c_scan_static_board_info(adap); | |
1618 | ||
4735c98f | 1619 | /* Notify drivers */ |
35fc37f8 | 1620 | mutex_lock(&core_lock); |
d6703281 | 1621 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 1622 | mutex_unlock(&core_lock); |
35fc37f8 JD |
1623 | |
1624 | return 0; | |
b119c6c9 | 1625 | |
b119c6c9 | 1626 | out_list: |
35fc37f8 | 1627 | mutex_lock(&core_lock); |
b119c6c9 | 1628 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
1629 | mutex_unlock(&core_lock); |
1630 | return res; | |
1da177e4 LT |
1631 | } |
1632 | ||
ee5c2744 DA |
1633 | /** |
1634 | * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 | |
1635 | * @adap: the adapter to register (with adap->nr initialized) | |
1636 | * Context: can sleep | |
1637 | * | |
1638 | * See i2c_add_numbered_adapter() for details. | |
1639 | */ | |
1640 | static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1641 | { | |
1642 | int id; | |
1643 | ||
1644 | mutex_lock(&core_lock); | |
1645 | id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, | |
1646 | GFP_KERNEL); | |
1647 | mutex_unlock(&core_lock); | |
1648 | if (id < 0) | |
1649 | return id == -ENOSPC ? -EBUSY : id; | |
1650 | ||
1651 | return i2c_register_adapter(adap); | |
1652 | } | |
1653 | ||
6e13e641 DB |
1654 | /** |
1655 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
1656 | * @adapter: the adapter to add | |
d64f73be | 1657 | * Context: can sleep |
6e13e641 DB |
1658 | * |
1659 | * This routine is used to declare an I2C adapter when its bus number | |
ee5c2744 DA |
1660 | * doesn't matter or when its bus number is specified by an dt alias. |
1661 | * Examples of bases when the bus number doesn't matter: I2C adapters | |
1662 | * dynamically added by USB links or PCI plugin cards. | |
6e13e641 DB |
1663 | * |
1664 | * When this returns zero, a new bus number was allocated and stored | |
1665 | * in adap->nr, and the specified adapter became available for clients. | |
1666 | * Otherwise, a negative errno value is returned. | |
1667 | */ | |
1668 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
1669 | { | |
ee5c2744 | 1670 | struct device *dev = &adapter->dev; |
4ae42b0f | 1671 | int id; |
6e13e641 | 1672 | |
ee5c2744 DA |
1673 | if (dev->of_node) { |
1674 | id = of_alias_get_id(dev->of_node, "i2c"); | |
1675 | if (id >= 0) { | |
1676 | adapter->nr = id; | |
1677 | return __i2c_add_numbered_adapter(adapter); | |
1678 | } | |
1679 | } | |
1680 | ||
caada32a | 1681 | mutex_lock(&core_lock); |
4ae42b0f TH |
1682 | id = idr_alloc(&i2c_adapter_idr, adapter, |
1683 | __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); | |
caada32a | 1684 | mutex_unlock(&core_lock); |
4ae42b0f TH |
1685 | if (id < 0) |
1686 | return id; | |
6e13e641 DB |
1687 | |
1688 | adapter->nr = id; | |
4ae42b0f | 1689 | |
6e13e641 DB |
1690 | return i2c_register_adapter(adapter); |
1691 | } | |
1692 | EXPORT_SYMBOL(i2c_add_adapter); | |
1693 | ||
1694 | /** | |
1695 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
1696 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 1697 | * Context: can sleep |
6e13e641 DB |
1698 | * |
1699 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
1700 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
1701 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
1702 | * is used to properly configure I2C devices. |
1703 | * | |
488bf314 GL |
1704 | * If the requested bus number is set to -1, then this function will behave |
1705 | * identically to i2c_add_adapter, and will dynamically assign a bus number. | |
1706 | * | |
6e13e641 DB |
1707 | * If no devices have pre-been declared for this bus, then be sure to |
1708 | * register the adapter before any dynamically allocated ones. Otherwise | |
1709 | * the required bus ID may not be available. | |
1710 | * | |
1711 | * When this returns zero, the specified adapter became available for | |
1712 | * clients using the bus number provided in adap->nr. Also, the table | |
1713 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
1714 | * and the appropriate driver model device nodes are created. Otherwise, a | |
1715 | * negative errno value is returned. | |
1716 | */ | |
1717 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1718 | { | |
488bf314 GL |
1719 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
1720 | return i2c_add_adapter(adap); | |
6e13e641 | 1721 | |
ee5c2744 | 1722 | return __i2c_add_numbered_adapter(adap); |
6e13e641 DB |
1723 | } |
1724 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
1725 | ||
19baba4c | 1726 | static void i2c_do_del_adapter(struct i2c_driver *driver, |
69b0089a | 1727 | struct i2c_adapter *adapter) |
026526f5 | 1728 | { |
4735c98f | 1729 | struct i2c_client *client, *_n; |
026526f5 | 1730 | |
acec211c JD |
1731 | /* Remove the devices we created ourselves as the result of hardware |
1732 | * probing (using a driver's detect method) */ | |
4735c98f JD |
1733 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
1734 | if (client->adapter == adapter) { | |
1735 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
1736 | client->name, client->addr); | |
1737 | list_del(&client->detected); | |
1738 | i2c_unregister_device(client); | |
1739 | } | |
1740 | } | |
026526f5 JD |
1741 | } |
1742 | ||
e549c2b5 | 1743 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
1744 | { |
1745 | struct i2c_client *client = i2c_verify_client(dev); | |
1746 | if (client && strcmp(client->name, "dummy")) | |
1747 | i2c_unregister_device(client); | |
1748 | return 0; | |
1749 | } | |
1750 | ||
1751 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1752 | { |
1753 | struct i2c_client *client = i2c_verify_client(dev); | |
1754 | if (client) | |
1755 | i2c_unregister_device(client); | |
1756 | return 0; | |
1757 | } | |
1758 | ||
69b0089a JD |
1759 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1760 | { | |
19baba4c LPC |
1761 | i2c_do_del_adapter(to_i2c_driver(d), data); |
1762 | return 0; | |
69b0089a JD |
1763 | } |
1764 | ||
d64f73be DB |
1765 | /** |
1766 | * i2c_del_adapter - unregister I2C adapter | |
1767 | * @adap: the adapter being unregistered | |
1768 | * Context: can sleep | |
1769 | * | |
1770 | * This unregisters an I2C adapter which was previously registered | |
1771 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1772 | */ | |
71546300 | 1773 | void i2c_del_adapter(struct i2c_adapter *adap) |
1da177e4 | 1774 | { |
35fc37f8 | 1775 | struct i2c_adapter *found; |
bbd2d9c9 | 1776 | struct i2c_client *client, *next; |
1da177e4 LT |
1777 | |
1778 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1779 | mutex_lock(&core_lock); |
1780 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1781 | mutex_unlock(&core_lock); | |
1782 | if (found != adap) { | |
b6d7b3d1 JD |
1783 | pr_debug("i2c-core: attempting to delete unregistered " |
1784 | "adapter [%s]\n", adap->name); | |
71546300 | 1785 | return; |
1da177e4 LT |
1786 | } |
1787 | ||
5d98e61d | 1788 | acpi_i2c_remove_space_handler(adap); |
026526f5 | 1789 | /* Tell drivers about this removal */ |
35fc37f8 | 1790 | mutex_lock(&core_lock); |
19baba4c | 1791 | bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1792 | __process_removed_adapter); |
35fc37f8 | 1793 | mutex_unlock(&core_lock); |
1da177e4 | 1794 | |
bbd2d9c9 | 1795 | /* Remove devices instantiated from sysfs */ |
390946b1 JD |
1796 | mutex_lock_nested(&adap->userspace_clients_lock, |
1797 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1798 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1799 | detected) { | |
1800 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1801 | client->addr); | |
1802 | list_del(&client->detected); | |
1803 | i2c_unregister_device(client); | |
bbd2d9c9 | 1804 | } |
dafc50d1 | 1805 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1806 | |
e549c2b5 | 1807 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1808 | * check the returned value. This is a two-pass process, because |
1809 | * we can't remove the dummy devices during the first pass: they | |
1810 | * could have been instantiated by real devices wishing to clean | |
1811 | * them up properly, so we give them a chance to do that first. */ | |
19baba4c LPC |
1812 | device_for_each_child(&adap->dev, NULL, __unregister_client); |
1813 | device_for_each_child(&adap->dev, NULL, __unregister_dummy); | |
1da177e4 | 1814 | |
2bb5095a JD |
1815 | #ifdef CONFIG_I2C_COMPAT |
1816 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1817 | adap->dev.parent); | |
1818 | #endif | |
1819 | ||
c5567521 TLSC |
1820 | /* device name is gone after device_unregister */ |
1821 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1822 | ||
9f924169 WS |
1823 | pm_runtime_disable(&adap->dev); |
1824 | ||
26680ee2 WS |
1825 | /* wait until all references to the device are gone |
1826 | * | |
1827 | * FIXME: This is old code and should ideally be replaced by an | |
1828 | * alternative which results in decoupling the lifetime of the struct | |
1829 | * device from the i2c_adapter, like spi or netdev do. Any solution | |
95cc1e3d | 1830 | * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! |
26680ee2 | 1831 | */ |
1da177e4 | 1832 | init_completion(&adap->dev_released); |
1da177e4 | 1833 | device_unregister(&adap->dev); |
1da177e4 | 1834 | wait_for_completion(&adap->dev_released); |
1da177e4 | 1835 | |
6e13e641 | 1836 | /* free bus id */ |
35fc37f8 | 1837 | mutex_lock(&core_lock); |
1da177e4 | 1838 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1839 | mutex_unlock(&core_lock); |
1da177e4 | 1840 | |
bd4bc3db JD |
1841 | /* Clear the device structure in case this adapter is ever going to be |
1842 | added again */ | |
1843 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1da177e4 | 1844 | } |
c0564606 | 1845 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 | 1846 | |
54177ccf WS |
1847 | /** |
1848 | * i2c_parse_fw_timings - get I2C related timing parameters from firmware | |
1849 | * @dev: The device to scan for I2C timing properties | |
1850 | * @t: the i2c_timings struct to be filled with values | |
1851 | * @use_defaults: bool to use sane defaults derived from the I2C specification | |
1852 | * when properties are not found, otherwise use 0 | |
1853 | * | |
1854 | * Scan the device for the generic I2C properties describing timing parameters | |
1855 | * for the signal and fill the given struct with the results. If a property was | |
1856 | * not found and use_defaults was true, then maximum timings are assumed which | |
1857 | * are derived from the I2C specification. If use_defaults is not used, the | |
1858 | * results will be 0, so drivers can apply their own defaults later. The latter | |
1859 | * is mainly intended for avoiding regressions of existing drivers which want | |
1860 | * to switch to this function. New drivers almost always should use the defaults. | |
1861 | */ | |
1862 | ||
1863 | void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) | |
1864 | { | |
1865 | int ret; | |
1866 | ||
1867 | memset(t, 0, sizeof(*t)); | |
1868 | ||
1869 | ret = device_property_read_u32(dev, "clock-frequency", &t->bus_freq_hz); | |
1870 | if (ret && use_defaults) | |
1871 | t->bus_freq_hz = 100000; | |
1872 | ||
1873 | ret = device_property_read_u32(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns); | |
1874 | if (ret && use_defaults) { | |
1875 | if (t->bus_freq_hz <= 100000) | |
1876 | t->scl_rise_ns = 1000; | |
1877 | else if (t->bus_freq_hz <= 400000) | |
1878 | t->scl_rise_ns = 300; | |
1879 | else | |
1880 | t->scl_rise_ns = 120; | |
1881 | } | |
1882 | ||
1883 | ret = device_property_read_u32(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns); | |
1884 | if (ret && use_defaults) { | |
1885 | if (t->bus_freq_hz <= 400000) | |
1886 | t->scl_fall_ns = 300; | |
1887 | else | |
1888 | t->scl_fall_ns = 120; | |
1889 | } | |
1890 | ||
1891 | device_property_read_u32(dev, "i2c-scl-internal-delay-ns", &t->scl_int_delay_ns); | |
1892 | ||
1893 | ret = device_property_read_u32(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns); | |
1894 | if (ret && use_defaults) | |
1895 | t->sda_fall_ns = t->scl_fall_ns; | |
1896 | } | |
1897 | EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); | |
1898 | ||
7b4fbc50 DB |
1899 | /* ------------------------------------------------------------------------- */ |
1900 | ||
7ae31482 JD |
1901 | int i2c_for_each_dev(void *data, int (*fn)(struct device *, void *)) |
1902 | { | |
1903 | int res; | |
1904 | ||
1905 | mutex_lock(&core_lock); | |
1906 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); | |
1907 | mutex_unlock(&core_lock); | |
1908 | ||
1909 | return res; | |
1910 | } | |
1911 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); | |
1912 | ||
69b0089a | 1913 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1914 | { |
4f8cf824 JD |
1915 | if (dev->type != &i2c_adapter_type) |
1916 | return 0; | |
69b0089a | 1917 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1918 | } |
1919 | ||
7b4fbc50 DB |
1920 | /* |
1921 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1922 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1923 | */ |
1924 | ||
de59cf9e | 1925 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1926 | { |
7eebcb7c | 1927 | int res; |
1da177e4 | 1928 | |
1d0b19c9 | 1929 | /* Can't register until after driver model init */ |
95026658 | 1930 | if (WARN_ON(!is_registered)) |
1d0b19c9 DB |
1931 | return -EAGAIN; |
1932 | ||
1da177e4 | 1933 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1934 | driver->driver.owner = owner; |
1da177e4 | 1935 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 1936 | |
729d6dd5 | 1937 | /* When registration returns, the driver core |
6e13e641 DB |
1938 | * will have called probe() for all matching-but-unbound devices. |
1939 | */ | |
1da177e4 LT |
1940 | res = driver_register(&driver->driver); |
1941 | if (res) | |
7eebcb7c | 1942 | return res; |
438d6c2c | 1943 | |
35d8b2e6 | 1944 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1945 | |
4735c98f JD |
1946 | INIT_LIST_HEAD(&driver->clients); |
1947 | /* Walk the adapters that are already present */ | |
7ae31482 | 1948 | i2c_for_each_dev(driver, __process_new_driver); |
35fc37f8 | 1949 | |
7f101a97 DY |
1950 | return 0; |
1951 | } | |
1952 | EXPORT_SYMBOL(i2c_register_driver); | |
1953 | ||
69b0089a | 1954 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1955 | { |
19baba4c LPC |
1956 | if (dev->type == &i2c_adapter_type) |
1957 | i2c_do_del_adapter(data, to_i2c_adapter(dev)); | |
1958 | return 0; | |
1da177e4 LT |
1959 | } |
1960 | ||
a1d9e6e4 DB |
1961 | /** |
1962 | * i2c_del_driver - unregister I2C driver | |
1963 | * @driver: the driver being unregistered | |
d64f73be | 1964 | * Context: can sleep |
a1d9e6e4 | 1965 | */ |
b3e82096 | 1966 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1967 | { |
7ae31482 | 1968 | i2c_for_each_dev(driver, __process_removed_driver); |
1da177e4 LT |
1969 | |
1970 | driver_unregister(&driver->driver); | |
35d8b2e6 | 1971 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1972 | } |
c0564606 | 1973 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1974 | |
7b4fbc50 DB |
1975 | /* ------------------------------------------------------------------------- */ |
1976 | ||
e48d3319 JD |
1977 | /** |
1978 | * i2c_use_client - increments the reference count of the i2c client structure | |
1979 | * @client: the client being referenced | |
1980 | * | |
1981 | * Each live reference to a client should be refcounted. The driver model does | |
1982 | * that automatically as part of driver binding, so that most drivers don't | |
1983 | * need to do this explicitly: they hold a reference until they're unbound | |
1984 | * from the device. | |
1985 | * | |
1986 | * A pointer to the client with the incremented reference counter is returned. | |
1987 | */ | |
1988 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 1989 | { |
6ea438ec DB |
1990 | if (client && get_device(&client->dev)) |
1991 | return client; | |
1992 | return NULL; | |
1da177e4 | 1993 | } |
c0564606 | 1994 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 1995 | |
e48d3319 JD |
1996 | /** |
1997 | * i2c_release_client - release a use of the i2c client structure | |
1998 | * @client: the client being no longer referenced | |
1999 | * | |
2000 | * Must be called when a user of a client is finished with it. | |
2001 | */ | |
2002 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 2003 | { |
6ea438ec DB |
2004 | if (client) |
2005 | put_device(&client->dev); | |
1da177e4 | 2006 | } |
c0564606 | 2007 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 2008 | |
9b766b81 DB |
2009 | struct i2c_cmd_arg { |
2010 | unsigned cmd; | |
2011 | void *arg; | |
2012 | }; | |
2013 | ||
2014 | static int i2c_cmd(struct device *dev, void *_arg) | |
2015 | { | |
2016 | struct i2c_client *client = i2c_verify_client(dev); | |
2017 | struct i2c_cmd_arg *arg = _arg; | |
0acc2b32 LPC |
2018 | struct i2c_driver *driver; |
2019 | ||
2020 | if (!client || !client->dev.driver) | |
2021 | return 0; | |
9b766b81 | 2022 | |
0acc2b32 LPC |
2023 | driver = to_i2c_driver(client->dev.driver); |
2024 | if (driver->command) | |
2025 | driver->command(client, arg->cmd, arg->arg); | |
9b766b81 DB |
2026 | return 0; |
2027 | } | |
2028 | ||
1da177e4 LT |
2029 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
2030 | { | |
9b766b81 | 2031 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 2032 | |
9b766b81 DB |
2033 | cmd_arg.cmd = cmd; |
2034 | cmd_arg.arg = arg; | |
2035 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 2036 | } |
c0564606 | 2037 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 | 2038 | |
ea7513bb PA |
2039 | #if IS_ENABLED(CONFIG_OF_DYNAMIC) |
2040 | static int of_i2c_notify(struct notifier_block *nb, unsigned long action, | |
2041 | void *arg) | |
2042 | { | |
2043 | struct of_reconfig_data *rd = arg; | |
2044 | struct i2c_adapter *adap; | |
2045 | struct i2c_client *client; | |
2046 | ||
2047 | switch (of_reconfig_get_state_change(action, rd)) { | |
2048 | case OF_RECONFIG_CHANGE_ADD: | |
2049 | adap = of_find_i2c_adapter_by_node(rd->dn->parent); | |
2050 | if (adap == NULL) | |
2051 | return NOTIFY_OK; /* not for us */ | |
2052 | ||
4f001fd3 PA |
2053 | if (of_node_test_and_set_flag(rd->dn, OF_POPULATED)) { |
2054 | put_device(&adap->dev); | |
2055 | return NOTIFY_OK; | |
2056 | } | |
2057 | ||
ea7513bb PA |
2058 | client = of_i2c_register_device(adap, rd->dn); |
2059 | put_device(&adap->dev); | |
2060 | ||
2061 | if (IS_ERR(client)) { | |
2062 | pr_err("%s: failed to create for '%s'\n", | |
2063 | __func__, rd->dn->full_name); | |
2064 | return notifier_from_errno(PTR_ERR(client)); | |
2065 | } | |
2066 | break; | |
2067 | case OF_RECONFIG_CHANGE_REMOVE: | |
4f001fd3 PA |
2068 | /* already depopulated? */ |
2069 | if (!of_node_check_flag(rd->dn, OF_POPULATED)) | |
2070 | return NOTIFY_OK; | |
2071 | ||
ea7513bb PA |
2072 | /* find our device by node */ |
2073 | client = of_find_i2c_device_by_node(rd->dn); | |
2074 | if (client == NULL) | |
2075 | return NOTIFY_OK; /* no? not meant for us */ | |
2076 | ||
2077 | /* unregister takes one ref away */ | |
2078 | i2c_unregister_device(client); | |
2079 | ||
2080 | /* and put the reference of the find */ | |
2081 | put_device(&client->dev); | |
2082 | break; | |
2083 | } | |
2084 | ||
2085 | return NOTIFY_OK; | |
2086 | } | |
2087 | static struct notifier_block i2c_of_notifier = { | |
2088 | .notifier_call = of_i2c_notify, | |
2089 | }; | |
2090 | #else | |
2091 | extern struct notifier_block i2c_of_notifier; | |
2092 | #endif /* CONFIG_OF_DYNAMIC */ | |
2093 | ||
1da177e4 LT |
2094 | static int __init i2c_init(void) |
2095 | { | |
2096 | int retval; | |
2097 | ||
03bde7c3 WS |
2098 | retval = of_alias_get_highest_id("i2c"); |
2099 | ||
2100 | down_write(&__i2c_board_lock); | |
2101 | if (retval >= __i2c_first_dynamic_bus_num) | |
2102 | __i2c_first_dynamic_bus_num = retval + 1; | |
2103 | up_write(&__i2c_board_lock); | |
2104 | ||
1da177e4 | 2105 | retval = bus_register(&i2c_bus_type); |
1da177e4 LT |
2106 | if (retval) |
2107 | return retval; | |
b980a26d WS |
2108 | |
2109 | is_registered = true; | |
2110 | ||
2bb5095a JD |
2111 | #ifdef CONFIG_I2C_COMPAT |
2112 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
2113 | if (!i2c_adapter_compat_class) { | |
2114 | retval = -ENOMEM; | |
2115 | goto bus_err; | |
2116 | } | |
2117 | #endif | |
e9f1373b DB |
2118 | retval = i2c_add_driver(&dummy_driver); |
2119 | if (retval) | |
2bb5095a | 2120 | goto class_err; |
ea7513bb PA |
2121 | |
2122 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) | |
2123 | WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); | |
2124 | ||
e9f1373b DB |
2125 | return 0; |
2126 | ||
2bb5095a JD |
2127 | class_err: |
2128 | #ifdef CONFIG_I2C_COMPAT | |
2129 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 2130 | bus_err: |
2bb5095a | 2131 | #endif |
b980a26d | 2132 | is_registered = false; |
e9f1373b DB |
2133 | bus_unregister(&i2c_bus_type); |
2134 | return retval; | |
1da177e4 LT |
2135 | } |
2136 | ||
2137 | static void __exit i2c_exit(void) | |
2138 | { | |
ea7513bb PA |
2139 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
2140 | WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); | |
e9f1373b | 2141 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
2142 | #ifdef CONFIG_I2C_COMPAT |
2143 | class_compat_unregister(i2c_adapter_compat_class); | |
2144 | #endif | |
1da177e4 | 2145 | bus_unregister(&i2c_bus_type); |
d9a83d62 | 2146 | tracepoint_synchronize_unregister(); |
1da177e4 LT |
2147 | } |
2148 | ||
a10f9e7c DB |
2149 | /* We must initialize early, because some subsystems register i2c drivers |
2150 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
2151 | */ | |
2152 | postcore_initcall(i2c_init); | |
1da177e4 LT |
2153 | module_exit(i2c_exit); |
2154 | ||
2155 | /* ---------------------------------------------------- | |
2156 | * the functional interface to the i2c busses. | |
2157 | * ---------------------------------------------------- | |
2158 | */ | |
2159 | ||
b7f62584 WS |
2160 | /* Check if val is exceeding the quirk IFF quirk is non 0 */ |
2161 | #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) | |
2162 | ||
2163 | static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) | |
2164 | { | |
2165 | dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", | |
2166 | err_msg, msg->addr, msg->len, | |
2167 | msg->flags & I2C_M_RD ? "read" : "write"); | |
2168 | return -EOPNOTSUPP; | |
2169 | } | |
2170 | ||
2171 | static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2172 | { | |
2173 | const struct i2c_adapter_quirks *q = adap->quirks; | |
2174 | int max_num = q->max_num_msgs, i; | |
2175 | bool do_len_check = true; | |
2176 | ||
2177 | if (q->flags & I2C_AQ_COMB) { | |
2178 | max_num = 2; | |
2179 | ||
2180 | /* special checks for combined messages */ | |
2181 | if (num == 2) { | |
2182 | if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) | |
2183 | return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); | |
2184 | ||
2185 | if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) | |
2186 | return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); | |
2187 | ||
2188 | if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) | |
2189 | return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); | |
2190 | ||
2191 | if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) | |
2192 | return i2c_quirk_error(adap, &msgs[0], "msg too long"); | |
2193 | ||
2194 | if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) | |
2195 | return i2c_quirk_error(adap, &msgs[1], "msg too long"); | |
2196 | ||
2197 | do_len_check = false; | |
2198 | } | |
2199 | } | |
2200 | ||
2201 | if (i2c_quirk_exceeded(num, max_num)) | |
2202 | return i2c_quirk_error(adap, &msgs[0], "too many messages"); | |
2203 | ||
2204 | for (i = 0; i < num; i++) { | |
2205 | u16 len = msgs[i].len; | |
2206 | ||
2207 | if (msgs[i].flags & I2C_M_RD) { | |
2208 | if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) | |
2209 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
2210 | } else { | |
2211 | if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) | |
2212 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
2213 | } | |
2214 | } | |
2215 | ||
2216 | return 0; | |
2217 | } | |
2218 | ||
b37d2a3a JD |
2219 | /** |
2220 | * __i2c_transfer - unlocked flavor of i2c_transfer | |
2221 | * @adap: Handle to I2C bus | |
2222 | * @msgs: One or more messages to execute before STOP is issued to | |
2223 | * terminate the operation; each message begins with a START. | |
2224 | * @num: Number of messages to be executed. | |
2225 | * | |
2226 | * Returns negative errno, else the number of messages executed. | |
2227 | * | |
2228 | * Adapter lock must be held when calling this function. No debug logging | |
2229 | * takes place. adap->algo->master_xfer existence isn't checked. | |
2230 | */ | |
2231 | int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2232 | { | |
2233 | unsigned long orig_jiffies; | |
2234 | int ret, try; | |
2235 | ||
b7f62584 WS |
2236 | if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) |
2237 | return -EOPNOTSUPP; | |
2238 | ||
d9a83d62 DH |
2239 | /* i2c_trace_msg gets enabled when tracepoint i2c_transfer gets |
2240 | * enabled. This is an efficient way of keeping the for-loop from | |
2241 | * being executed when not needed. | |
2242 | */ | |
2243 | if (static_key_false(&i2c_trace_msg)) { | |
2244 | int i; | |
2245 | for (i = 0; i < num; i++) | |
2246 | if (msgs[i].flags & I2C_M_RD) | |
2247 | trace_i2c_read(adap, &msgs[i], i); | |
2248 | else | |
2249 | trace_i2c_write(adap, &msgs[i], i); | |
2250 | } | |
2251 | ||
b37d2a3a JD |
2252 | /* Retry automatically on arbitration loss */ |
2253 | orig_jiffies = jiffies; | |
2254 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
2255 | ret = adap->algo->master_xfer(adap, msgs, num); | |
2256 | if (ret != -EAGAIN) | |
2257 | break; | |
2258 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
2259 | break; | |
2260 | } | |
2261 | ||
d9a83d62 DH |
2262 | if (static_key_false(&i2c_trace_msg)) { |
2263 | int i; | |
2264 | for (i = 0; i < ret; i++) | |
2265 | if (msgs[i].flags & I2C_M_RD) | |
2266 | trace_i2c_reply(adap, &msgs[i], i); | |
2267 | trace_i2c_result(adap, i, ret); | |
2268 | } | |
2269 | ||
b37d2a3a JD |
2270 | return ret; |
2271 | } | |
2272 | EXPORT_SYMBOL(__i2c_transfer); | |
2273 | ||
a1cdedac DB |
2274 | /** |
2275 | * i2c_transfer - execute a single or combined I2C message | |
2276 | * @adap: Handle to I2C bus | |
2277 | * @msgs: One or more messages to execute before STOP is issued to | |
2278 | * terminate the operation; each message begins with a START. | |
2279 | * @num: Number of messages to be executed. | |
2280 | * | |
2281 | * Returns negative errno, else the number of messages executed. | |
2282 | * | |
2283 | * Note that there is no requirement that each message be sent to | |
2284 | * the same slave address, although that is the most common model. | |
2285 | */ | |
09b8ce0a | 2286 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 2287 | { |
b37d2a3a | 2288 | int ret; |
1da177e4 | 2289 | |
a1cdedac DB |
2290 | /* REVISIT the fault reporting model here is weak: |
2291 | * | |
2292 | * - When we get an error after receiving N bytes from a slave, | |
2293 | * there is no way to report "N". | |
2294 | * | |
2295 | * - When we get a NAK after transmitting N bytes to a slave, | |
2296 | * there is no way to report "N" ... or to let the master | |
2297 | * continue executing the rest of this combined message, if | |
2298 | * that's the appropriate response. | |
2299 | * | |
2300 | * - When for example "num" is two and we successfully complete | |
2301 | * the first message but get an error part way through the | |
2302 | * second, it's unclear whether that should be reported as | |
2303 | * one (discarding status on the second message) or errno | |
2304 | * (discarding status on the first one). | |
2305 | */ | |
2306 | ||
1da177e4 LT |
2307 | if (adap->algo->master_xfer) { |
2308 | #ifdef DEBUG | |
2309 | for (ret = 0; ret < num; ret++) { | |
2310 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
2311 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
2312 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
2313 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
2314 | } |
2315 | #endif | |
2316 | ||
cea443a8 | 2317 | if (in_atomic() || irqs_disabled()) { |
fe61e07e | 2318 | ret = i2c_trylock_adapter(adap); |
cea443a8 MR |
2319 | if (!ret) |
2320 | /* I2C activity is ongoing. */ | |
2321 | return -EAGAIN; | |
2322 | } else { | |
fe61e07e | 2323 | i2c_lock_adapter(adap); |
cea443a8 MR |
2324 | } |
2325 | ||
b37d2a3a | 2326 | ret = __i2c_transfer(adap, msgs, num); |
fe61e07e | 2327 | i2c_unlock_adapter(adap); |
1da177e4 LT |
2328 | |
2329 | return ret; | |
2330 | } else { | |
2331 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
24a5bb7b | 2332 | return -EOPNOTSUPP; |
1da177e4 LT |
2333 | } |
2334 | } | |
c0564606 | 2335 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 2336 | |
a1cdedac DB |
2337 | /** |
2338 | * i2c_master_send - issue a single I2C message in master transmit mode | |
2339 | * @client: Handle to slave device | |
2340 | * @buf: Data that will be written to the slave | |
0c43ea54 | 2341 | * @count: How many bytes to write, must be less than 64k since msg.len is u16 |
a1cdedac DB |
2342 | * |
2343 | * Returns negative errno, or else the number of bytes written. | |
2344 | */ | |
0cc43a18 | 2345 | int i2c_master_send(const struct i2c_client *client, const char *buf, int count) |
1da177e4 LT |
2346 | { |
2347 | int ret; | |
7225acf4 | 2348 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
2349 | struct i2c_msg msg; |
2350 | ||
815f55f2 JD |
2351 | msg.addr = client->addr; |
2352 | msg.flags = client->flags & I2C_M_TEN; | |
2353 | msg.len = count; | |
2354 | msg.buf = (char *)buf; | |
438d6c2c | 2355 | |
815f55f2 | 2356 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 2357 | |
834aa6f3 WS |
2358 | /* |
2359 | * If everything went ok (i.e. 1 msg transmitted), return #bytes | |
2360 | * transmitted, else error code. | |
2361 | */ | |
815f55f2 | 2362 | return (ret == 1) ? count : ret; |
1da177e4 | 2363 | } |
c0564606 | 2364 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 | 2365 | |
a1cdedac DB |
2366 | /** |
2367 | * i2c_master_recv - issue a single I2C message in master receive mode | |
2368 | * @client: Handle to slave device | |
2369 | * @buf: Where to store data read from slave | |
0c43ea54 | 2370 | * @count: How many bytes to read, must be less than 64k since msg.len is u16 |
a1cdedac DB |
2371 | * |
2372 | * Returns negative errno, or else the number of bytes read. | |
2373 | */ | |
0cc43a18 | 2374 | int i2c_master_recv(const struct i2c_client *client, char *buf, int count) |
1da177e4 | 2375 | { |
7225acf4 | 2376 | struct i2c_adapter *adap = client->adapter; |
1da177e4 LT |
2377 | struct i2c_msg msg; |
2378 | int ret; | |
815f55f2 JD |
2379 | |
2380 | msg.addr = client->addr; | |
2381 | msg.flags = client->flags & I2C_M_TEN; | |
2382 | msg.flags |= I2C_M_RD; | |
2383 | msg.len = count; | |
2384 | msg.buf = buf; | |
2385 | ||
2386 | ret = i2c_transfer(adap, &msg, 1); | |
2387 | ||
834aa6f3 WS |
2388 | /* |
2389 | * If everything went ok (i.e. 1 msg received), return #bytes received, | |
2390 | * else error code. | |
2391 | */ | |
815f55f2 | 2392 | return (ret == 1) ? count : ret; |
1da177e4 | 2393 | } |
c0564606 | 2394 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 2395 | |
1da177e4 LT |
2396 | /* ---------------------------------------------------- |
2397 | * the i2c address scanning function | |
2398 | * Will not work for 10-bit addresses! | |
2399 | * ---------------------------------------------------- | |
2400 | */ | |
1da177e4 | 2401 | |
63e4e802 JD |
2402 | /* |
2403 | * Legacy default probe function, mostly relevant for SMBus. The default | |
2404 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
2405 | * EEPROMs due to a state machine bug, and could also irreversibly | |
2406 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
2407 | * we use a short byte read instead. Also, some bus drivers don't implement | |
2408 | * quick write, so we fallback to a byte read in that case too. | |
2409 | * On x86, there is another special case for FSC hardware monitoring chips, | |
2410 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
2411 | * only known chips using this I2C address on PC hardware. | |
2412 | * Returns 1 if probe succeeded, 0 if not. | |
2413 | */ | |
2414 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
2415 | { | |
2416 | int err; | |
2417 | union i2c_smbus_data dummy; | |
2418 | ||
2419 | #ifdef CONFIG_X86 | |
2420 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
2421 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
2422 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2423 | I2C_SMBUS_BYTE_DATA, &dummy); | |
2424 | else | |
2425 | #endif | |
8031d79b JD |
2426 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
2427 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
2428 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
2429 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
2430 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
2431 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2432 | I2C_SMBUS_BYTE, &dummy); | |
2433 | else { | |
d63a9e85 AL |
2434 | dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", |
2435 | addr); | |
8031d79b JD |
2436 | err = -EOPNOTSUPP; |
2437 | } | |
63e4e802 JD |
2438 | |
2439 | return err >= 0; | |
2440 | } | |
2441 | ||
ccfbbd08 | 2442 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
2443 | struct i2c_driver *driver) |
2444 | { | |
2445 | struct i2c_board_info info; | |
2446 | struct i2c_adapter *adapter = temp_client->adapter; | |
2447 | int addr = temp_client->addr; | |
2448 | int err; | |
2449 | ||
2450 | /* Make sure the address is valid */ | |
66be6056 | 2451 | err = i2c_check_7bit_addr_validity_strict(addr); |
656b8761 | 2452 | if (err) { |
4735c98f JD |
2453 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
2454 | addr); | |
656b8761 | 2455 | return err; |
4735c98f JD |
2456 | } |
2457 | ||
9bccc70a | 2458 | /* Skip if already in use (7 bit, no need to encode flags) */ |
3b5f794b | 2459 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
2460 | return 0; |
2461 | ||
ccfbbd08 | 2462 | /* Make sure there is something at this address */ |
63e4e802 JD |
2463 | if (!i2c_default_probe(adapter, addr)) |
2464 | return 0; | |
4735c98f JD |
2465 | |
2466 | /* Finally call the custom detection function */ | |
2467 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
2468 | info.addr = addr; | |
310ec792 | 2469 | err = driver->detect(temp_client, &info); |
4735c98f JD |
2470 | if (err) { |
2471 | /* -ENODEV is returned if the detection fails. We catch it | |
2472 | here as this isn't an error. */ | |
2473 | return err == -ENODEV ? 0 : err; | |
2474 | } | |
2475 | ||
2476 | /* Consistency check */ | |
2477 | if (info.type[0] == '\0') { | |
2478 | dev_err(&adapter->dev, "%s detection function provided " | |
2479 | "no name for 0x%x\n", driver->driver.name, | |
2480 | addr); | |
2481 | } else { | |
2482 | struct i2c_client *client; | |
2483 | ||
2484 | /* Detection succeeded, instantiate the device */ | |
0c176170 WS |
2485 | if (adapter->class & I2C_CLASS_DEPRECATED) |
2486 | dev_warn(&adapter->dev, | |
2487 | "This adapter will soon drop class based instantiation of devices. " | |
2488 | "Please make sure client 0x%02x gets instantiated by other means. " | |
2489 | "Check 'Documentation/i2c/instantiating-devices' for details.\n", | |
2490 | info.addr); | |
2491 | ||
4735c98f JD |
2492 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", |
2493 | info.type, info.addr); | |
2494 | client = i2c_new_device(adapter, &info); | |
2495 | if (client) | |
2496 | list_add_tail(&client->detected, &driver->clients); | |
2497 | else | |
2498 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
2499 | info.type, info.addr); | |
2500 | } | |
2501 | return 0; | |
2502 | } | |
2503 | ||
2504 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
2505 | { | |
c3813d6a | 2506 | const unsigned short *address_list; |
4735c98f JD |
2507 | struct i2c_client *temp_client; |
2508 | int i, err = 0; | |
2509 | int adap_id = i2c_adapter_id(adapter); | |
2510 | ||
c3813d6a JD |
2511 | address_list = driver->address_list; |
2512 | if (!driver->detect || !address_list) | |
4735c98f JD |
2513 | return 0; |
2514 | ||
45552272 WS |
2515 | /* Warn that the adapter lost class based instantiation */ |
2516 | if (adapter->class == I2C_CLASS_DEPRECATED) { | |
2517 | dev_dbg(&adapter->dev, | |
2518 | "This adapter dropped support for I2C classes and " | |
2519 | "won't auto-detect %s devices anymore. If you need it, check " | |
2520 | "'Documentation/i2c/instantiating-devices' for alternatives.\n", | |
2521 | driver->driver.name); | |
2522 | return 0; | |
2523 | } | |
2524 | ||
51b54ba9 JD |
2525 | /* Stop here if the classes do not match */ |
2526 | if (!(adapter->class & driver->class)) | |
2527 | return 0; | |
2528 | ||
4735c98f JD |
2529 | /* Set up a temporary client to help detect callback */ |
2530 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
2531 | if (!temp_client) | |
2532 | return -ENOMEM; | |
2533 | temp_client->adapter = adapter; | |
2534 | ||
c3813d6a | 2535 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
4735c98f | 2536 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
c3813d6a JD |
2537 | "addr 0x%02x\n", adap_id, address_list[i]); |
2538 | temp_client->addr = address_list[i]; | |
ccfbbd08 | 2539 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
2540 | if (unlikely(err)) |
2541 | break; | |
4735c98f JD |
2542 | } |
2543 | ||
4735c98f JD |
2544 | kfree(temp_client); |
2545 | return err; | |
2546 | } | |
2547 | ||
d44f19d5 JD |
2548 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
2549 | { | |
2550 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2551 | I2C_SMBUS_QUICK, NULL) >= 0; | |
2552 | } | |
2553 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
2554 | ||
12b5053a JD |
2555 | struct i2c_client * |
2556 | i2c_new_probed_device(struct i2c_adapter *adap, | |
2557 | struct i2c_board_info *info, | |
9a94241a JD |
2558 | unsigned short const *addr_list, |
2559 | int (*probe)(struct i2c_adapter *, unsigned short addr)) | |
12b5053a JD |
2560 | { |
2561 | int i; | |
2562 | ||
8031d79b | 2563 | if (!probe) |
9a94241a | 2564 | probe = i2c_default_probe; |
12b5053a | 2565 | |
12b5053a JD |
2566 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
2567 | /* Check address validity */ | |
66be6056 | 2568 | if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { |
12b5053a JD |
2569 | dev_warn(&adap->dev, "Invalid 7-bit address " |
2570 | "0x%02x\n", addr_list[i]); | |
2571 | continue; | |
2572 | } | |
2573 | ||
9bccc70a | 2574 | /* Check address availability (7 bit, no need to encode flags) */ |
3b5f794b | 2575 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
12b5053a JD |
2576 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
2577 | "use, not probing\n", addr_list[i]); | |
2578 | continue; | |
2579 | } | |
2580 | ||
63e4e802 | 2581 | /* Test address responsiveness */ |
9a94241a | 2582 | if (probe(adap, addr_list[i])) |
63e4e802 | 2583 | break; |
12b5053a | 2584 | } |
12b5053a JD |
2585 | |
2586 | if (addr_list[i] == I2C_CLIENT_END) { | |
2587 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
2588 | return NULL; | |
2589 | } | |
2590 | ||
2591 | info->addr = addr_list[i]; | |
2592 | return i2c_new_device(adap, info); | |
2593 | } | |
2594 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
2595 | ||
d735b34d | 2596 | struct i2c_adapter *i2c_get_adapter(int nr) |
1da177e4 | 2597 | { |
1da177e4 | 2598 | struct i2c_adapter *adapter; |
438d6c2c | 2599 | |
caada32a | 2600 | mutex_lock(&core_lock); |
d735b34d | 2601 | adapter = idr_find(&i2c_adapter_idr, nr); |
611e12ea VZ |
2602 | if (!adapter) |
2603 | goto exit; | |
2604 | ||
2605 | if (try_module_get(adapter->owner)) | |
2606 | get_device(&adapter->dev); | |
2607 | else | |
a0920e10 MH |
2608 | adapter = NULL; |
2609 | ||
611e12ea | 2610 | exit: |
caada32a | 2611 | mutex_unlock(&core_lock); |
a0920e10 | 2612 | return adapter; |
1da177e4 | 2613 | } |
c0564606 | 2614 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
2615 | |
2616 | void i2c_put_adapter(struct i2c_adapter *adap) | |
2617 | { | |
611e12ea VZ |
2618 | if (!adap) |
2619 | return; | |
2620 | ||
2621 | put_device(&adap->dev); | |
2622 | module_put(adap->owner); | |
1da177e4 | 2623 | } |
c0564606 | 2624 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
2625 | |
2626 | /* The SMBus parts */ | |
2627 | ||
438d6c2c | 2628 | #define POLY (0x1070U << 3) |
09b8ce0a | 2629 | static u8 crc8(u16 data) |
1da177e4 LT |
2630 | { |
2631 | int i; | |
438d6c2c | 2632 | |
7225acf4 | 2633 | for (i = 0; i < 8; i++) { |
438d6c2c | 2634 | if (data & 0x8000) |
1da177e4 LT |
2635 | data = data ^ POLY; |
2636 | data = data << 1; | |
2637 | } | |
2638 | return (u8)(data >> 8); | |
2639 | } | |
2640 | ||
421ef47b JD |
2641 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
2642 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
2643 | { |
2644 | int i; | |
2645 | ||
7225acf4 | 2646 | for (i = 0; i < count; i++) |
421ef47b | 2647 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
2648 | return crc; |
2649 | } | |
2650 | ||
421ef47b JD |
2651 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
2652 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 2653 | { |
421ef47b JD |
2654 | /* The address will be sent first */ |
2655 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
2656 | pec = i2c_smbus_pec(pec, &addr, 1); | |
2657 | ||
2658 | /* The data buffer follows */ | |
2659 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
2660 | } |
2661 | ||
421ef47b JD |
2662 | /* Used for write only transactions */ |
2663 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 2664 | { |
421ef47b JD |
2665 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
2666 | msg->len++; | |
1da177e4 LT |
2667 | } |
2668 | ||
421ef47b JD |
2669 | /* Return <0 on CRC error |
2670 | If there was a write before this read (most cases) we need to take the | |
2671 | partial CRC from the write part into account. | |
2672 | Note that this function does modify the message (we need to decrease the | |
2673 | message length to hide the CRC byte from the caller). */ | |
2674 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 2675 | { |
421ef47b JD |
2676 | u8 rpec = msg->buf[--msg->len]; |
2677 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 2678 | |
1da177e4 LT |
2679 | if (rpec != cpec) { |
2680 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
2681 | rpec, cpec); | |
24a5bb7b | 2682 | return -EBADMSG; |
1da177e4 | 2683 | } |
438d6c2c | 2684 | return 0; |
1da177e4 LT |
2685 | } |
2686 | ||
a1cdedac DB |
2687 | /** |
2688 | * i2c_smbus_read_byte - SMBus "receive byte" protocol | |
2689 | * @client: Handle to slave device | |
2690 | * | |
2691 | * This executes the SMBus "receive byte" protocol, returning negative errno | |
2692 | * else the byte received from the device. | |
2693 | */ | |
0cc43a18 | 2694 | s32 i2c_smbus_read_byte(const struct i2c_client *client) |
1da177e4 LT |
2695 | { |
2696 | union i2c_smbus_data data; | |
24a5bb7b DB |
2697 | int status; |
2698 | ||
2699 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2700 | I2C_SMBUS_READ, 0, | |
2701 | I2C_SMBUS_BYTE, &data); | |
2702 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2703 | } |
c0564606 | 2704 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 | 2705 | |
a1cdedac DB |
2706 | /** |
2707 | * i2c_smbus_write_byte - SMBus "send byte" protocol | |
2708 | * @client: Handle to slave device | |
2709 | * @value: Byte to be sent | |
2710 | * | |
2711 | * This executes the SMBus "send byte" protocol, returning negative errno | |
2712 | * else zero on success. | |
2713 | */ | |
0cc43a18 | 2714 | s32 i2c_smbus_write_byte(const struct i2c_client *client, u8 value) |
1da177e4 | 2715 | { |
7225acf4 | 2716 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
421ef47b | 2717 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 2718 | } |
c0564606 | 2719 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 | 2720 | |
a1cdedac DB |
2721 | /** |
2722 | * i2c_smbus_read_byte_data - SMBus "read byte" protocol | |
2723 | * @client: Handle to slave device | |
2724 | * @command: Byte interpreted by slave | |
2725 | * | |
2726 | * This executes the SMBus "read byte" protocol, returning negative errno | |
2727 | * else a data byte received from the device. | |
2728 | */ | |
0cc43a18 | 2729 | s32 i2c_smbus_read_byte_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2730 | { |
2731 | union i2c_smbus_data data; | |
24a5bb7b DB |
2732 | int status; |
2733 | ||
2734 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2735 | I2C_SMBUS_READ, command, | |
2736 | I2C_SMBUS_BYTE_DATA, &data); | |
2737 | return (status < 0) ? status : data.byte; | |
1da177e4 | 2738 | } |
c0564606 | 2739 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 | 2740 | |
a1cdedac DB |
2741 | /** |
2742 | * i2c_smbus_write_byte_data - SMBus "write byte" protocol | |
2743 | * @client: Handle to slave device | |
2744 | * @command: Byte interpreted by slave | |
2745 | * @value: Byte being written | |
2746 | * | |
2747 | * This executes the SMBus "write byte" protocol, returning negative errno | |
2748 | * else zero on success. | |
2749 | */ | |
0cc43a18 JD |
2750 | s32 i2c_smbus_write_byte_data(const struct i2c_client *client, u8 command, |
2751 | u8 value) | |
1da177e4 LT |
2752 | { |
2753 | union i2c_smbus_data data; | |
2754 | data.byte = value; | |
7225acf4 FH |
2755 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2756 | I2C_SMBUS_WRITE, command, | |
2757 | I2C_SMBUS_BYTE_DATA, &data); | |
1da177e4 | 2758 | } |
c0564606 | 2759 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 | 2760 | |
a1cdedac DB |
2761 | /** |
2762 | * i2c_smbus_read_word_data - SMBus "read word" protocol | |
2763 | * @client: Handle to slave device | |
2764 | * @command: Byte interpreted by slave | |
2765 | * | |
2766 | * This executes the SMBus "read word" protocol, returning negative errno | |
2767 | * else a 16-bit unsigned "word" received from the device. | |
2768 | */ | |
0cc43a18 | 2769 | s32 i2c_smbus_read_word_data(const struct i2c_client *client, u8 command) |
1da177e4 LT |
2770 | { |
2771 | union i2c_smbus_data data; | |
24a5bb7b DB |
2772 | int status; |
2773 | ||
2774 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2775 | I2C_SMBUS_READ, command, | |
2776 | I2C_SMBUS_WORD_DATA, &data); | |
2777 | return (status < 0) ? status : data.word; | |
1da177e4 | 2778 | } |
c0564606 | 2779 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 | 2780 | |
a1cdedac DB |
2781 | /** |
2782 | * i2c_smbus_write_word_data - SMBus "write word" protocol | |
2783 | * @client: Handle to slave device | |
2784 | * @command: Byte interpreted by slave | |
2785 | * @value: 16-bit "word" being written | |
2786 | * | |
2787 | * This executes the SMBus "write word" protocol, returning negative errno | |
2788 | * else zero on success. | |
2789 | */ | |
0cc43a18 JD |
2790 | s32 i2c_smbus_write_word_data(const struct i2c_client *client, u8 command, |
2791 | u16 value) | |
1da177e4 LT |
2792 | { |
2793 | union i2c_smbus_data data; | |
2794 | data.word = value; | |
7225acf4 FH |
2795 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2796 | I2C_SMBUS_WRITE, command, | |
2797 | I2C_SMBUS_WORD_DATA, &data); | |
1da177e4 | 2798 | } |
c0564606 | 2799 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 2800 | |
a64ec07d | 2801 | /** |
a1cdedac | 2802 | * i2c_smbus_read_block_data - SMBus "block read" protocol |
a64ec07d | 2803 | * @client: Handle to slave device |
a1cdedac | 2804 | * @command: Byte interpreted by slave |
a64ec07d DB |
2805 | * @values: Byte array into which data will be read; big enough to hold |
2806 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
2807 | * | |
a1cdedac DB |
2808 | * This executes the SMBus "block read" protocol, returning negative errno |
2809 | * else the number of data bytes in the slave's response. | |
a64ec07d DB |
2810 | * |
2811 | * Note that using this function requires that the client's adapter support | |
2812 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
2813 | * support this; its emulation through I2C messaging relies on a specific | |
2814 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
2815 | */ | |
0cc43a18 | 2816 | s32 i2c_smbus_read_block_data(const struct i2c_client *client, u8 command, |
b86a1bc8 JD |
2817 | u8 *values) |
2818 | { | |
2819 | union i2c_smbus_data data; | |
24a5bb7b | 2820 | int status; |
b86a1bc8 | 2821 | |
24a5bb7b DB |
2822 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2823 | I2C_SMBUS_READ, command, | |
2824 | I2C_SMBUS_BLOCK_DATA, &data); | |
2825 | if (status) | |
2826 | return status; | |
b86a1bc8 JD |
2827 | |
2828 | memcpy(values, &data.block[1], data.block[0]); | |
2829 | return data.block[0]; | |
2830 | } | |
2831 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
2832 | ||
a1cdedac DB |
2833 | /** |
2834 | * i2c_smbus_write_block_data - SMBus "block write" protocol | |
2835 | * @client: Handle to slave device | |
2836 | * @command: Byte interpreted by slave | |
2837 | * @length: Size of data block; SMBus allows at most 32 bytes | |
2838 | * @values: Byte array which will be written. | |
2839 | * | |
2840 | * This executes the SMBus "block write" protocol, returning negative errno | |
2841 | * else zero on success. | |
2842 | */ | |
0cc43a18 | 2843 | s32 i2c_smbus_write_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2844 | u8 length, const u8 *values) |
1da177e4 LT |
2845 | { |
2846 | union i2c_smbus_data data; | |
7656032b | 2847 | |
1da177e4 LT |
2848 | if (length > I2C_SMBUS_BLOCK_MAX) |
2849 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 2850 | data.block[0] = length; |
7656032b | 2851 | memcpy(&data.block[1], values, length); |
7225acf4 FH |
2852 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2853 | I2C_SMBUS_WRITE, command, | |
2854 | I2C_SMBUS_BLOCK_DATA, &data); | |
1da177e4 | 2855 | } |
c0564606 | 2856 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
2857 | |
2858 | /* Returns the number of read bytes */ | |
0cc43a18 | 2859 | s32 i2c_smbus_read_i2c_block_data(const struct i2c_client *client, u8 command, |
4b2643d7 | 2860 | u8 length, u8 *values) |
1da177e4 LT |
2861 | { |
2862 | union i2c_smbus_data data; | |
24a5bb7b | 2863 | int status; |
7656032b | 2864 | |
4b2643d7 JD |
2865 | if (length > I2C_SMBUS_BLOCK_MAX) |
2866 | length = I2C_SMBUS_BLOCK_MAX; | |
2867 | data.block[0] = length; | |
24a5bb7b DB |
2868 | status = i2c_smbus_xfer(client->adapter, client->addr, client->flags, |
2869 | I2C_SMBUS_READ, command, | |
2870 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2871 | if (status < 0) | |
2872 | return status; | |
7656032b JD |
2873 | |
2874 | memcpy(values, &data.block[1], data.block[0]); | |
2875 | return data.block[0]; | |
1da177e4 | 2876 | } |
c0564606 | 2877 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 2878 | |
0cc43a18 | 2879 | s32 i2c_smbus_write_i2c_block_data(const struct i2c_client *client, u8 command, |
46f5ed75 | 2880 | u8 length, const u8 *values) |
21bbd691 JD |
2881 | { |
2882 | union i2c_smbus_data data; | |
2883 | ||
2884 | if (length > I2C_SMBUS_BLOCK_MAX) | |
2885 | length = I2C_SMBUS_BLOCK_MAX; | |
2886 | data.block[0] = length; | |
2887 | memcpy(data.block + 1, values, length); | |
2888 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
2889 | I2C_SMBUS_WRITE, command, | |
2890 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
2891 | } | |
c0564606 | 2892 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 2893 | |
438d6c2c | 2894 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 2895 | No checking of parameters is done! */ |
7225acf4 FH |
2896 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter *adapter, u16 addr, |
2897 | unsigned short flags, | |
2898 | char read_write, u8 command, int size, | |
2899 | union i2c_smbus_data *data) | |
1da177e4 LT |
2900 | { |
2901 | /* So we need to generate a series of msgs. In the case of writing, we | |
2902 | need to use only one message; when reading, we need two. We initialize | |
2903 | most things with sane defaults, to keep the code below somewhat | |
2904 | simpler. */ | |
5c50d188 HI |
2905 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
2906 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
7225acf4 | 2907 | int num = read_write == I2C_SMBUS_READ ? 2 : 1; |
1da177e4 | 2908 | int i; |
421ef47b | 2909 | u8 partial_pec = 0; |
24a5bb7b | 2910 | int status; |
230da094 S |
2911 | struct i2c_msg msg[2] = { |
2912 | { | |
2913 | .addr = addr, | |
2914 | .flags = flags, | |
2915 | .len = 1, | |
2916 | .buf = msgbuf0, | |
2917 | }, { | |
2918 | .addr = addr, | |
2919 | .flags = flags | I2C_M_RD, | |
2920 | .len = 0, | |
2921 | .buf = msgbuf1, | |
2922 | }, | |
2923 | }; | |
1da177e4 LT |
2924 | |
2925 | msgbuf0[0] = command; | |
7225acf4 | 2926 | switch (size) { |
1da177e4 LT |
2927 | case I2C_SMBUS_QUICK: |
2928 | msg[0].len = 0; | |
2929 | /* Special case: The read/write field is used as data */ | |
f29d2e02 RK |
2930 | msg[0].flags = flags | (read_write == I2C_SMBUS_READ ? |
2931 | I2C_M_RD : 0); | |
1da177e4 LT |
2932 | num = 1; |
2933 | break; | |
2934 | case I2C_SMBUS_BYTE: | |
2935 | if (read_write == I2C_SMBUS_READ) { | |
2936 | /* Special case: only a read! */ | |
2937 | msg[0].flags = I2C_M_RD | flags; | |
2938 | num = 1; | |
2939 | } | |
2940 | break; | |
2941 | case I2C_SMBUS_BYTE_DATA: | |
2942 | if (read_write == I2C_SMBUS_READ) | |
2943 | msg[1].len = 1; | |
2944 | else { | |
2945 | msg[0].len = 2; | |
2946 | msgbuf0[1] = data->byte; | |
2947 | } | |
2948 | break; | |
2949 | case I2C_SMBUS_WORD_DATA: | |
2950 | if (read_write == I2C_SMBUS_READ) | |
2951 | msg[1].len = 2; | |
2952 | else { | |
7225acf4 | 2953 | msg[0].len = 3; |
1da177e4 | 2954 | msgbuf0[1] = data->word & 0xff; |
7eff82c8 | 2955 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2956 | } |
2957 | break; | |
2958 | case I2C_SMBUS_PROC_CALL: | |
2959 | num = 2; /* Special case */ | |
2960 | read_write = I2C_SMBUS_READ; | |
2961 | msg[0].len = 3; | |
2962 | msg[1].len = 2; | |
2963 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 2964 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
2965 | break; |
2966 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 2967 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
2968 | msg[1].flags |= I2C_M_RECV_LEN; |
2969 | msg[1].len = 1; /* block length will be added by | |
2970 | the underlying bus driver */ | |
1da177e4 LT |
2971 | } else { |
2972 | msg[0].len = data->block[0] + 2; | |
2973 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
24a5bb7b DB |
2974 | dev_err(&adapter->dev, |
2975 | "Invalid block write size %d\n", | |
2976 | data->block[0]); | |
2977 | return -EINVAL; | |
1da177e4 | 2978 | } |
5c50d188 | 2979 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
2980 | msgbuf0[i] = data->block[i-1]; |
2981 | } | |
2982 | break; | |
2983 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
2984 | num = 2; /* Another special case */ |
2985 | read_write = I2C_SMBUS_READ; | |
2986 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
24a5bb7b DB |
2987 | dev_err(&adapter->dev, |
2988 | "Invalid block write size %d\n", | |
209d27c3 | 2989 | data->block[0]); |
24a5bb7b | 2990 | return -EINVAL; |
209d27c3 JD |
2991 | } |
2992 | msg[0].len = data->block[0] + 2; | |
2993 | for (i = 1; i < msg[0].len; i++) | |
2994 | msgbuf0[i] = data->block[i-1]; | |
2995 | msg[1].flags |= I2C_M_RECV_LEN; | |
2996 | msg[1].len = 1; /* block length will be added by | |
2997 | the underlying bus driver */ | |
2998 | break; | |
1da177e4 LT |
2999 | case I2C_SMBUS_I2C_BLOCK_DATA: |
3000 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 3001 | msg[1].len = data->block[0]; |
1da177e4 LT |
3002 | } else { |
3003 | msg[0].len = data->block[0] + 1; | |
30dac746 | 3004 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
24a5bb7b DB |
3005 | dev_err(&adapter->dev, |
3006 | "Invalid block write size %d\n", | |
3007 | data->block[0]); | |
3008 | return -EINVAL; | |
1da177e4 LT |
3009 | } |
3010 | for (i = 1; i <= data->block[0]; i++) | |
3011 | msgbuf0[i] = data->block[i]; | |
3012 | } | |
3013 | break; | |
3014 | default: | |
24a5bb7b DB |
3015 | dev_err(&adapter->dev, "Unsupported transaction %d\n", size); |
3016 | return -EOPNOTSUPP; | |
1da177e4 LT |
3017 | } |
3018 | ||
421ef47b JD |
3019 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
3020 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
3021 | if (i) { | |
3022 | /* Compute PEC if first message is a write */ | |
3023 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 3024 | if (num == 1) /* Write only */ |
421ef47b JD |
3025 | i2c_smbus_add_pec(&msg[0]); |
3026 | else /* Write followed by read */ | |
3027 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
3028 | } | |
3029 | /* Ask for PEC if last message is a read */ | |
3030 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 3031 | msg[num-1].len++; |
421ef47b JD |
3032 | } |
3033 | ||
24a5bb7b DB |
3034 | status = i2c_transfer(adapter, msg, num); |
3035 | if (status < 0) | |
3036 | return status; | |
1da177e4 | 3037 | |
421ef47b JD |
3038 | /* Check PEC if last message is a read */ |
3039 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
24a5bb7b DB |
3040 | status = i2c_smbus_check_pec(partial_pec, &msg[num-1]); |
3041 | if (status < 0) | |
3042 | return status; | |
421ef47b JD |
3043 | } |
3044 | ||
1da177e4 | 3045 | if (read_write == I2C_SMBUS_READ) |
7225acf4 FH |
3046 | switch (size) { |
3047 | case I2C_SMBUS_BYTE: | |
3048 | data->byte = msgbuf0[0]; | |
3049 | break; | |
3050 | case I2C_SMBUS_BYTE_DATA: | |
3051 | data->byte = msgbuf1[0]; | |
3052 | break; | |
3053 | case I2C_SMBUS_WORD_DATA: | |
3054 | case I2C_SMBUS_PROC_CALL: | |
3055 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
3056 | break; | |
3057 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
3058 | for (i = 0; i < data->block[0]; i++) | |
3059 | data->block[i+1] = msgbuf1[i]; | |
3060 | break; | |
3061 | case I2C_SMBUS_BLOCK_DATA: | |
3062 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
3063 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
3064 | data->block[i] = msgbuf1[i]; | |
3065 | break; | |
1da177e4 LT |
3066 | } |
3067 | return 0; | |
3068 | } | |
3069 | ||
a1cdedac DB |
3070 | /** |
3071 | * i2c_smbus_xfer - execute SMBus protocol operations | |
3072 | * @adapter: Handle to I2C bus | |
3073 | * @addr: Address of SMBus slave on that bus | |
3074 | * @flags: I2C_CLIENT_* flags (usually zero or I2C_CLIENT_PEC) | |
3075 | * @read_write: I2C_SMBUS_READ or I2C_SMBUS_WRITE | |
3076 | * @command: Byte interpreted by slave, for protocols which use such bytes | |
3077 | * @protocol: SMBus protocol operation to execute, such as I2C_SMBUS_PROC_CALL | |
3078 | * @data: Data to be read or written | |
3079 | * | |
3080 | * This executes an SMBus protocol operation, and returns a negative | |
3081 | * errno code else zero on success. | |
3082 | */ | |
09b8ce0a | 3083 | s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr, unsigned short flags, |
a1cdedac | 3084 | char read_write, u8 command, int protocol, |
09b8ce0a | 3085 | union i2c_smbus_data *data) |
1da177e4 | 3086 | { |
66b650f0 CW |
3087 | unsigned long orig_jiffies; |
3088 | int try; | |
1da177e4 | 3089 | s32 res; |
1da177e4 | 3090 | |
8a325997 DH |
3091 | /* If enabled, the following two tracepoints are conditional on |
3092 | * read_write and protocol. | |
3093 | */ | |
3094 | trace_smbus_write(adapter, addr, flags, read_write, | |
3095 | command, protocol, data); | |
3096 | trace_smbus_read(adapter, addr, flags, read_write, | |
3097 | command, protocol); | |
3098 | ||
d47726c5 | 3099 | flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB; |
1da177e4 LT |
3100 | |
3101 | if (adapter->algo->smbus_xfer) { | |
fe61e07e | 3102 | i2c_lock_adapter(adapter); |
66b650f0 CW |
3103 | |
3104 | /* Retry automatically on arbitration loss */ | |
3105 | orig_jiffies = jiffies; | |
3106 | for (res = 0, try = 0; try <= adapter->retries; try++) { | |
3107 | res = adapter->algo->smbus_xfer(adapter, addr, flags, | |
3108 | read_write, command, | |
3109 | protocol, data); | |
3110 | if (res != -EAGAIN) | |
3111 | break; | |
3112 | if (time_after(jiffies, | |
3113 | orig_jiffies + adapter->timeout)) | |
3114 | break; | |
3115 | } | |
fe61e07e | 3116 | i2c_unlock_adapter(adapter); |
1da177e4 | 3117 | |
72fc2c7f | 3118 | if (res != -EOPNOTSUPP || !adapter->algo->master_xfer) |
8a325997 | 3119 | goto trace; |
72fc2c7f LP |
3120 | /* |
3121 | * Fall back to i2c_smbus_xfer_emulated if the adapter doesn't | |
3122 | * implement native support for the SMBus operation. | |
3123 | */ | |
3124 | } | |
3125 | ||
8a325997 DH |
3126 | res = i2c_smbus_xfer_emulated(adapter, addr, flags, read_write, |
3127 | command, protocol, data); | |
3128 | ||
3129 | trace: | |
3130 | /* If enabled, the reply tracepoint is conditional on read_write. */ | |
3131 | trace_smbus_reply(adapter, addr, flags, read_write, | |
3132 | command, protocol, data); | |
3133 | trace_smbus_result(adapter, addr, flags, read_write, | |
3134 | command, protocol, res); | |
3135 | ||
3136 | return res; | |
1da177e4 | 3137 | } |
1da177e4 | 3138 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 | 3139 | |
01eef96e IT |
3140 | /** |
3141 | * i2c_smbus_read_i2c_block_data_or_emulated - read block or emulate | |
3142 | * @client: Handle to slave device | |
3143 | * @command: Byte interpreted by slave | |
3144 | * @length: Size of data block; SMBus allows at most I2C_SMBUS_BLOCK_MAX bytes | |
3145 | * @values: Byte array into which data will be read; big enough to hold | |
3146 | * the data returned by the slave. SMBus allows at most | |
3147 | * I2C_SMBUS_BLOCK_MAX bytes. | |
3148 | * | |
3149 | * This executes the SMBus "block read" protocol if supported by the adapter. | |
3150 | * If block read is not supported, it emulates it using either word or byte | |
3151 | * read protocols depending on availability. | |
3152 | * | |
3153 | * The addresses of the I2C slave device that are accessed with this function | |
3154 | * must be mapped to a linear region, so that a block read will have the same | |
3155 | * effect as a byte read. Before using this function you must double-check | |
3156 | * if the I2C slave does support exchanging a block transfer with a byte | |
3157 | * transfer. | |
3158 | */ | |
3159 | s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, | |
3160 | u8 command, u8 length, u8 *values) | |
3161 | { | |
3162 | u8 i = 0; | |
3163 | int status; | |
3164 | ||
3165 | if (length > I2C_SMBUS_BLOCK_MAX) | |
3166 | length = I2C_SMBUS_BLOCK_MAX; | |
3167 | ||
3168 | if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) | |
3169 | return i2c_smbus_read_i2c_block_data(client, command, length, values); | |
3170 | ||
3171 | if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
3172 | return -EOPNOTSUPP; | |
3173 | ||
3174 | if (i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_READ_WORD_DATA)) { | |
3175 | while ((i + 2) <= length) { | |
3176 | status = i2c_smbus_read_word_data(client, command + i); | |
3177 | if (status < 0) | |
3178 | return status; | |
3179 | values[i] = status & 0xff; | |
3180 | values[i + 1] = status >> 8; | |
3181 | i += 2; | |
3182 | } | |
3183 | } | |
3184 | ||
3185 | while (i < length) { | |
3186 | status = i2c_smbus_read_byte_data(client, command + i); | |
3187 | if (status < 0) | |
3188 | return status; | |
3189 | values[i] = status; | |
3190 | i++; | |
3191 | } | |
3192 | ||
3193 | return i; | |
3194 | } | |
3195 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated); | |
3196 | ||
d5fd120e | 3197 | #if IS_ENABLED(CONFIG_I2C_SLAVE) |
4b1acc43 WS |
3198 | int i2c_slave_register(struct i2c_client *client, i2c_slave_cb_t slave_cb) |
3199 | { | |
3200 | int ret; | |
3201 | ||
0c7cab96 WS |
3202 | if (!client || !slave_cb) { |
3203 | WARN(1, "insufficent data\n"); | |
4b1acc43 | 3204 | return -EINVAL; |
0c7cab96 | 3205 | } |
4b1acc43 | 3206 | |
c6909d6f WS |
3207 | if (!(client->flags & I2C_CLIENT_SLAVE)) |
3208 | dev_warn(&client->dev, "%s: client slave flag not set. You might see address collisions\n", | |
3209 | __func__); | |
3210 | ||
4b1acc43 WS |
3211 | if (!(client->flags & I2C_CLIENT_TEN)) { |
3212 | /* Enforce stricter address checking */ | |
66be6056 | 3213 | ret = i2c_check_7bit_addr_validity_strict(client->addr); |
0c7cab96 WS |
3214 | if (ret) { |
3215 | dev_err(&client->dev, "%s: invalid address\n", __func__); | |
4b1acc43 | 3216 | return ret; |
0c7cab96 | 3217 | } |
4b1acc43 WS |
3218 | } |
3219 | ||
0c7cab96 WS |
3220 | if (!client->adapter->algo->reg_slave) { |
3221 | dev_err(&client->dev, "%s: not supported by adapter\n", __func__); | |
4b1acc43 | 3222 | return -EOPNOTSUPP; |
0c7cab96 | 3223 | } |
4b1acc43 WS |
3224 | |
3225 | client->slave_cb = slave_cb; | |
3226 | ||
3227 | i2c_lock_adapter(client->adapter); | |
3228 | ret = client->adapter->algo->reg_slave(client); | |
3229 | i2c_unlock_adapter(client->adapter); | |
3230 | ||
0c7cab96 | 3231 | if (ret) { |
4b1acc43 | 3232 | client->slave_cb = NULL; |
0c7cab96 WS |
3233 | dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); |
3234 | } | |
4b1acc43 WS |
3235 | |
3236 | return ret; | |
3237 | } | |
3238 | EXPORT_SYMBOL_GPL(i2c_slave_register); | |
3239 | ||
3240 | int i2c_slave_unregister(struct i2c_client *client) | |
3241 | { | |
3242 | int ret; | |
3243 | ||
0c7cab96 WS |
3244 | if (!client->adapter->algo->unreg_slave) { |
3245 | dev_err(&client->dev, "%s: not supported by adapter\n", __func__); | |
4b1acc43 | 3246 | return -EOPNOTSUPP; |
0c7cab96 | 3247 | } |
4b1acc43 WS |
3248 | |
3249 | i2c_lock_adapter(client->adapter); | |
3250 | ret = client->adapter->algo->unreg_slave(client); | |
3251 | i2c_unlock_adapter(client->adapter); | |
3252 | ||
3253 | if (ret == 0) | |
3254 | client->slave_cb = NULL; | |
0c7cab96 WS |
3255 | else |
3256 | dev_err(&client->dev, "%s: adapter returned error %d\n", __func__, ret); | |
4b1acc43 WS |
3257 | |
3258 | return ret; | |
3259 | } | |
3260 | EXPORT_SYMBOL_GPL(i2c_slave_unregister); | |
d5fd120e | 3261 | #endif |
4b1acc43 | 3262 | |
1da177e4 LT |
3263 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); |
3264 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
3265 | MODULE_LICENSE("GPL"); |