Commit | Line | Data |
---|---|---|
c942fddf | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
61e3d0f7 WS |
2 | /* |
3 | * Linux I2C core | |
4 | * | |
5 | * Copyright (C) 1995-99 Simon G. Vogl | |
6 | * With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi> | |
7 | * Mux support by Rodolfo Giometti <giometti@enneenne.com> and | |
8 | * Michael Lawnick <michael.lawnick.ext@nsn.com> | |
9 | * | |
2f5a55c5 | 10 | * Copyright (C) 2013-2017 Wolfram Sang <wsa@kernel.org> |
687b81d0 | 11 | */ |
1da177e4 | 12 | |
44239a5a WS |
13 | #define pr_fmt(fmt) "i2c-core: " fmt |
14 | ||
b4e2f6ac | 15 | #include <dt-bindings/i2c/i2c.h> |
53feedf8 WS |
16 | #include <linux/acpi.h> |
17 | #include <linux/clk/clk-conf.h> | |
18 | #include <linux/completion.h> | |
5f9296ba | 19 | #include <linux/delay.h> |
53feedf8 | 20 | #include <linux/err.h> |
1da177e4 | 21 | #include <linux/errno.h> |
10c9ef04 | 22 | #include <linux/gpio/consumer.h> |
1da177e4 | 23 | #include <linux/i2c.h> |
f8756c67 | 24 | #include <linux/i2c-smbus.h> |
1da177e4 | 25 | #include <linux/idr.h> |
53feedf8 WS |
26 | #include <linux/init.h> |
27 | #include <linux/irqflags.h> | |
28 | #include <linux/jump_label.h> | |
29 | #include <linux/kernel.h> | |
30 | #include <linux/module.h> | |
b3585e4f | 31 | #include <linux/mutex.h> |
959e85f7 | 32 | #include <linux/of_device.h> |
53feedf8 | 33 | #include <linux/of.h> |
687b81d0 | 34 | #include <linux/of_irq.h> |
75820314 | 35 | #include <linux/pinctrl/consumer.h> |
f48c767c | 36 | #include <linux/pm_domain.h> |
53feedf8 | 37 | #include <linux/pm_runtime.h> |
3fffd128 | 38 | #include <linux/pm_wakeirq.h> |
e1dba01c | 39 | #include <linux/property.h> |
53feedf8 WS |
40 | #include <linux/rwsem.h> |
41 | #include <linux/slab.h> | |
1da177e4 | 42 | |
9c1600ed DB |
43 | #include "i2c-core.h" |
44 | ||
d9a83d62 DH |
45 | #define CREATE_TRACE_POINTS |
46 | #include <trace/events/i2c.h> | |
1da177e4 | 47 | |
da899f55 WS |
48 | #define I2C_ADDR_OFFSET_TEN_BIT 0xa000 |
49 | #define I2C_ADDR_OFFSET_SLAVE 0x1000 | |
50 | ||
4d5538f5 BT |
51 | #define I2C_ADDR_7BITS_MAX 0x77 |
52 | #define I2C_ADDR_7BITS_COUNT (I2C_ADDR_7BITS_MAX + 1) | |
53 | ||
dde67eb1 PR |
54 | #define I2C_ADDR_DEVICE_ID 0x7c |
55 | ||
61e3d0f7 WS |
56 | /* |
57 | * core_lock protects i2c_adapter_idr, and guarantees that device detection, | |
0c36dd37 | 58 | * deletion of detected devices are serialized |
61e3d0f7 | 59 | */ |
caada32a | 60 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
61 | static DEFINE_IDR(i2c_adapter_idr); |
62 | ||
4735c98f | 63 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver); |
f37dd80a | 64 | |
50888b01 | 65 | static DEFINE_STATIC_KEY_FALSE(i2c_trace_msg_key); |
95026658 | 66 | static bool is_registered; |
d9a83d62 | 67 | |
8cf868af | 68 | int i2c_transfer_trace_reg(void) |
d9a83d62 | 69 | { |
50888b01 | 70 | static_branch_inc(&i2c_trace_msg_key); |
8cf868af | 71 | return 0; |
d9a83d62 DH |
72 | } |
73 | ||
74 | void i2c_transfer_trace_unreg(void) | |
75 | { | |
50888b01 | 76 | static_branch_dec(&i2c_trace_msg_key); |
d9a83d62 DH |
77 | } |
78 | ||
5f441fca | 79 | const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
d2653e92 JD |
80 | const struct i2c_client *client) |
81 | { | |
811073b1 LJ |
82 | if (!(id && client)) |
83 | return NULL; | |
84 | ||
d2653e92 JD |
85 | while (id->name[0]) { |
86 | if (strcmp(client->name, id->name) == 0) | |
87 | return id; | |
88 | id++; | |
89 | } | |
90 | return NULL; | |
91 | } | |
5f441fca | 92 | EXPORT_SYMBOL_GPL(i2c_match_id); |
d2653e92 | 93 | |
1da177e4 LT |
94 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
95 | { | |
51298d12 JD |
96 | struct i2c_client *client = i2c_verify_client(dev); |
97 | struct i2c_driver *driver; | |
98 | ||
7b4fbc50 | 99 | |
959e85f7 | 100 | /* Attempt an OF style match */ |
da10c06a | 101 | if (i2c_of_match_device(drv->of_match_table, client)) |
959e85f7 GL |
102 | return 1; |
103 | ||
907ddf89 MW |
104 | /* Then ACPI style match */ |
105 | if (acpi_driver_match_device(dev, drv)) | |
106 | return 1; | |
107 | ||
51298d12 | 108 | driver = to_i2c_driver(drv); |
811073b1 LJ |
109 | |
110 | /* Finally an I2C match */ | |
111 | if (i2c_match_id(driver->id_table, client)) | |
112 | return 1; | |
d2653e92 | 113 | |
eb8a7908 | 114 | return 0; |
1da177e4 LT |
115 | } |
116 | ||
7eff2e7a | 117 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 | 118 | { |
8dcf3217 | 119 | struct i2c_client *client = to_i2c_client(dev); |
8c4ff6d0 ZR |
120 | int rc; |
121 | ||
af503716 JMC |
122 | rc = of_device_uevent_modalias(dev, env); |
123 | if (rc != -ENODEV) | |
124 | return rc; | |
125 | ||
8c4ff6d0 ZR |
126 | rc = acpi_device_uevent_modalias(dev, env); |
127 | if (rc != -ENODEV) | |
128 | return rc; | |
7b4fbc50 | 129 | |
8dcf3217 | 130 | return add_uevent_var(env, "MODALIAS=%s%s", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
131 | } |
132 | ||
5f9296ba VK |
133 | /* i2c bus recovery routines */ |
134 | static int get_scl_gpio_value(struct i2c_adapter *adap) | |
135 | { | |
3991c5c8 | 136 | return gpiod_get_value_cansleep(adap->bus_recovery_info->scl_gpiod); |
5f9296ba VK |
137 | } |
138 | ||
139 | static void set_scl_gpio_value(struct i2c_adapter *adap, int val) | |
140 | { | |
3991c5c8 | 141 | gpiod_set_value_cansleep(adap->bus_recovery_info->scl_gpiod, val); |
5f9296ba VK |
142 | } |
143 | ||
144 | static int get_sda_gpio_value(struct i2c_adapter *adap) | |
145 | { | |
3991c5c8 | 146 | return gpiod_get_value_cansleep(adap->bus_recovery_info->sda_gpiod); |
5f9296ba VK |
147 | } |
148 | ||
8092178f | 149 | static void set_sda_gpio_value(struct i2c_adapter *adap, int val) |
5f9296ba | 150 | { |
8092178f | 151 | gpiod_set_value_cansleep(adap->bus_recovery_info->sda_gpiod, val); |
5f9296ba VK |
152 | } |
153 | ||
7ca5f6be WS |
154 | static int i2c_generic_bus_free(struct i2c_adapter *adap) |
155 | { | |
156 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
157 | int ret = -EOPNOTSUPP; | |
158 | ||
159 | if (bri->get_bus_free) | |
160 | ret = bri->get_bus_free(adap); | |
161 | else if (bri->get_sda) | |
162 | ret = bri->get_sda(adap); | |
163 | ||
164 | if (ret < 0) | |
165 | return ret; | |
166 | ||
167 | return ret ? 0 : -EBUSY; | |
168 | } | |
169 | ||
5f9296ba VK |
170 | /* |
171 | * We are generating clock pulses. ndelay() determines durating of clk pulses. | |
172 | * We will generate clock with rate 100 KHz and so duration of both clock levels | |
173 | * is: delay in ns = (10^6 / 100) / 2 | |
174 | */ | |
175 | #define RECOVERY_NDELAY 5000 | |
176 | #define RECOVERY_CLK_CNT 9 | |
177 | ||
e1eb7d28 | 178 | int i2c_generic_scl_recovery(struct i2c_adapter *adap) |
5f9296ba VK |
179 | { |
180 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
cf676908 | 181 | int i = 0, scl = 1, ret = 0; |
5f9296ba VK |
182 | |
183 | if (bri->prepare_recovery) | |
2b2190a3 | 184 | bri->prepare_recovery(adap); |
75820314 CC |
185 | if (bri->pinctrl) |
186 | pinctrl_select_state(bri->pinctrl, bri->pins_gpio); | |
5f9296ba | 187 | |
c4ae05b9 WS |
188 | /* |
189 | * If we can set SDA, we will always create a STOP to ensure additional | |
190 | * pulses will do no harm. This is achieved by letting SDA follow SCL | |
191 | * half a cycle later. Check the 'incomplete_write_byte' fault injector | |
cf8ce8b8 RK |
192 | * for details. Note that we must honour tsu:sto, 4us, but lets use 5us |
193 | * here for simplicity. | |
c4ae05b9 | 194 | */ |
f7ff75e2 | 195 | bri->set_scl(adap, scl); |
cf8ce8b8 | 196 | ndelay(RECOVERY_NDELAY); |
72b08fcc | 197 | if (bri->set_sda) |
c4ae05b9 WS |
198 | bri->set_sda(adap, scl); |
199 | ndelay(RECOVERY_NDELAY / 2); | |
8b062608 | 200 | |
5f9296ba VK |
201 | /* |
202 | * By this time SCL is high, as we need to give 9 falling-rising edges | |
203 | */ | |
204 | while (i++ < RECOVERY_CLK_CNT * 2) { | |
f7ff75e2 | 205 | if (scl) { |
5f9296ba VK |
206 | /* SCL shouldn't be low here */ |
207 | if (!bri->get_scl(adap)) { | |
208 | dev_err(&adap->dev, | |
209 | "SCL is stuck low, exit recovery\n"); | |
210 | ret = -EBUSY; | |
211 | break; | |
212 | } | |
213 | } | |
214 | ||
f7ff75e2 WS |
215 | scl = !scl; |
216 | bri->set_scl(adap, scl); | |
c4ae05b9 | 217 | /* Creating STOP again, see above */ |
cf8ce8b8 RK |
218 | if (scl) { |
219 | /* Honour minimum tsu:sto */ | |
220 | ndelay(RECOVERY_NDELAY); | |
221 | } else { | |
222 | /* Honour minimum tf and thd:dat */ | |
223 | ndelay(RECOVERY_NDELAY / 2); | |
224 | } | |
abe41184 | 225 | if (bri->set_sda) |
f7ff75e2 | 226 | bri->set_sda(adap, scl); |
abe41184 | 227 | ndelay(RECOVERY_NDELAY / 2); |
1f35b865 | 228 | |
f7ff75e2 | 229 | if (scl) { |
7ca5f6be | 230 | ret = i2c_generic_bus_free(adap); |
0b71026c WS |
231 | if (ret == 0) |
232 | break; | |
233 | } | |
2806e6ad WS |
234 | } |
235 | ||
7ca5f6be WS |
236 | /* If we can't check bus status, assume recovery worked */ |
237 | if (ret == -EOPNOTSUPP) | |
238 | ret = 0; | |
239 | ||
5f9296ba | 240 | if (bri->unprepare_recovery) |
2b2190a3 | 241 | bri->unprepare_recovery(adap); |
75820314 CC |
242 | if (bri->pinctrl) |
243 | pinctrl_select_state(bri->pinctrl, bri->pins_default); | |
5f9296ba VK |
244 | |
245 | return ret; | |
246 | } | |
c1c21f4e | 247 | EXPORT_SYMBOL_GPL(i2c_generic_scl_recovery); |
5f9296ba | 248 | |
5f9296ba VK |
249 | int i2c_recover_bus(struct i2c_adapter *adap) |
250 | { | |
251 | if (!adap->bus_recovery_info) | |
252 | return -EOPNOTSUPP; | |
253 | ||
254 | dev_dbg(&adap->dev, "Trying i2c bus recovery\n"); | |
255 | return adap->bus_recovery_info->recover_bus(adap); | |
256 | } | |
c1c21f4e | 257 | EXPORT_SYMBOL_GPL(i2c_recover_bus); |
5f9296ba | 258 | |
75820314 CC |
259 | static void i2c_gpio_init_pinctrl_recovery(struct i2c_adapter *adap) |
260 | { | |
261 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
262 | struct device *dev = &adap->dev; | |
263 | struct pinctrl *p = bri->pinctrl; | |
264 | ||
265 | /* | |
266 | * we can't change states without pinctrl, so remove the states if | |
267 | * populated | |
268 | */ | |
269 | if (!p) { | |
270 | bri->pins_default = NULL; | |
271 | bri->pins_gpio = NULL; | |
272 | return; | |
273 | } | |
274 | ||
275 | if (!bri->pins_default) { | |
276 | bri->pins_default = pinctrl_lookup_state(p, | |
277 | PINCTRL_STATE_DEFAULT); | |
278 | if (IS_ERR(bri->pins_default)) { | |
279 | dev_dbg(dev, PINCTRL_STATE_DEFAULT " state not found for GPIO recovery\n"); | |
280 | bri->pins_default = NULL; | |
281 | } | |
282 | } | |
283 | if (!bri->pins_gpio) { | |
284 | bri->pins_gpio = pinctrl_lookup_state(p, "gpio"); | |
285 | if (IS_ERR(bri->pins_gpio)) | |
286 | bri->pins_gpio = pinctrl_lookup_state(p, "recovery"); | |
287 | ||
288 | if (IS_ERR(bri->pins_gpio)) { | |
289 | dev_dbg(dev, "no gpio or recovery state found for GPIO recovery\n"); | |
290 | bri->pins_gpio = NULL; | |
291 | } | |
292 | } | |
293 | ||
294 | /* for pinctrl state changes, we need all the information */ | |
295 | if (bri->pins_default && bri->pins_gpio) { | |
296 | dev_info(dev, "using pinctrl states for GPIO recovery"); | |
297 | } else { | |
298 | bri->pinctrl = NULL; | |
299 | bri->pins_default = NULL; | |
300 | bri->pins_gpio = NULL; | |
301 | } | |
302 | } | |
303 | ||
304 | static int i2c_gpio_init_generic_recovery(struct i2c_adapter *adap) | |
305 | { | |
306 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
307 | struct device *dev = &adap->dev; | |
308 | struct gpio_desc *gpiod; | |
309 | int ret = 0; | |
310 | ||
311 | /* | |
312 | * don't touch the recovery information if the driver is not using | |
313 | * generic SCL recovery | |
314 | */ | |
315 | if (bri->recover_bus && bri->recover_bus != i2c_generic_scl_recovery) | |
316 | return 0; | |
317 | ||
318 | /* | |
319 | * pins might be taken as GPIO, so we should inform pinctrl about | |
320 | * this and move the state to GPIO | |
321 | */ | |
322 | if (bri->pinctrl) | |
323 | pinctrl_select_state(bri->pinctrl, bri->pins_gpio); | |
324 | ||
325 | /* | |
326 | * if there is incomplete or no recovery information, see if generic | |
327 | * GPIO recovery is available | |
328 | */ | |
329 | if (!bri->scl_gpiod) { | |
330 | gpiod = devm_gpiod_get(dev, "scl", GPIOD_OUT_HIGH_OPEN_DRAIN); | |
331 | if (PTR_ERR(gpiod) == -EPROBE_DEFER) { | |
332 | ret = -EPROBE_DEFER; | |
333 | goto cleanup_pinctrl_state; | |
334 | } | |
335 | if (!IS_ERR(gpiod)) { | |
336 | bri->scl_gpiod = gpiod; | |
337 | bri->recover_bus = i2c_generic_scl_recovery; | |
338 | dev_info(dev, "using generic GPIOs for recovery\n"); | |
339 | } | |
340 | } | |
341 | ||
342 | /* SDA GPIOD line is optional, so we care about DEFER only */ | |
343 | if (!bri->sda_gpiod) { | |
344 | /* | |
345 | * We have SCL. Pull SCL low and wait a bit so that SDA glitches | |
346 | * have no effect. | |
347 | */ | |
348 | gpiod_direction_output(bri->scl_gpiod, 0); | |
349 | udelay(10); | |
350 | gpiod = devm_gpiod_get(dev, "sda", GPIOD_IN); | |
351 | ||
352 | /* Wait a bit in case of a SDA glitch, and then release SCL. */ | |
353 | udelay(10); | |
354 | gpiod_direction_output(bri->scl_gpiod, 1); | |
355 | ||
356 | if (PTR_ERR(gpiod) == -EPROBE_DEFER) { | |
357 | ret = -EPROBE_DEFER; | |
358 | goto cleanup_pinctrl_state; | |
359 | } | |
360 | if (!IS_ERR(gpiod)) | |
361 | bri->sda_gpiod = gpiod; | |
362 | } | |
363 | ||
364 | cleanup_pinctrl_state: | |
365 | /* change the state of the pins back to their default state */ | |
366 | if (bri->pinctrl) | |
367 | pinctrl_select_state(bri->pinctrl, bri->pins_default); | |
368 | ||
369 | return ret; | |
370 | } | |
371 | ||
372 | static int i2c_gpio_init_recovery(struct i2c_adapter *adap) | |
373 | { | |
374 | i2c_gpio_init_pinctrl_recovery(adap); | |
375 | return i2c_gpio_init_generic_recovery(adap); | |
376 | } | |
377 | ||
23a698fe | 378 | static int i2c_init_recovery(struct i2c_adapter *adap) |
d3b11d83 WS |
379 | { |
380 | struct i2c_bus_recovery_info *bri = adap->bus_recovery_info; | |
381 | char *err_str; | |
382 | ||
383 | if (!bri) | |
23a698fe | 384 | return 0; |
d3b11d83 | 385 | |
23a698fe CC |
386 | if (i2c_gpio_init_recovery(adap) == -EPROBE_DEFER) |
387 | return -EPROBE_DEFER; | |
75820314 | 388 | |
d3b11d83 WS |
389 | if (!bri->recover_bus) { |
390 | err_str = "no recover_bus() found"; | |
391 | goto err; | |
392 | } | |
393 | ||
3991c5c8 | 394 | if (bri->scl_gpiod && bri->recover_bus == i2c_generic_scl_recovery) { |
d3b11d83 WS |
395 | bri->get_scl = get_scl_gpio_value; |
396 | bri->set_scl = set_scl_gpio_value; | |
8092178f | 397 | if (bri->sda_gpiod) { |
3991c5c8 | 398 | bri->get_sda = get_sda_gpio_value; |
8092178f WS |
399 | /* FIXME: add proper flag instead of '0' once available */ |
400 | if (gpiod_get_direction(bri->sda_gpiod) == 0) | |
401 | bri->set_sda = set_sda_gpio_value; | |
402 | } | |
23a698fe | 403 | } else if (bri->recover_bus == i2c_generic_scl_recovery) { |
d3b11d83 WS |
404 | /* Generic SCL recovery */ |
405 | if (!bri->set_scl || !bri->get_scl) { | |
406 | err_str = "no {get|set}_scl() found"; | |
407 | goto err; | |
408 | } | |
ffc59c49 WS |
409 | if (!bri->set_sda && !bri->get_sda) { |
410 | err_str = "either get_sda() or set_sda() needed"; | |
411 | goto err; | |
412 | } | |
d3b11d83 WS |
413 | } |
414 | ||
23a698fe | 415 | return 0; |
d3b11d83 WS |
416 | err: |
417 | dev_err(&adap->dev, "Not using recovery: %s\n", err_str); | |
418 | adap->bus_recovery_info = NULL; | |
23a698fe CC |
419 | |
420 | return -EINVAL; | |
d3b11d83 WS |
421 | } |
422 | ||
4d5538f5 BT |
423 | static int i2c_smbus_host_notify_to_irq(const struct i2c_client *client) |
424 | { | |
425 | struct i2c_adapter *adap = client->adapter; | |
426 | unsigned int irq; | |
427 | ||
428 | if (!adap->host_notify_domain) | |
429 | return -ENXIO; | |
430 | ||
431 | if (client->flags & I2C_CLIENT_TEN) | |
432 | return -EINVAL; | |
433 | ||
b9bb3fdf | 434 | irq = irq_create_mapping(adap->host_notify_domain, client->addr); |
4d5538f5 BT |
435 | |
436 | return irq > 0 ? irq : -ENXIO; | |
437 | } | |
438 | ||
f37dd80a | 439 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 440 | { |
51298d12 JD |
441 | struct i2c_client *client = i2c_verify_client(dev); |
442 | struct i2c_driver *driver; | |
50c3304a | 443 | int status; |
7b4fbc50 | 444 | |
51298d12 JD |
445 | if (!client) |
446 | return 0; | |
447 | ||
6e76cb7d CK |
448 | client->irq = client->init_irq; |
449 | ||
0c2a3493 | 450 | if (!client->irq) { |
845c8770 MW |
451 | int irq = -ENOENT; |
452 | ||
331c3425 DT |
453 | if (client->flags & I2C_CLIENT_HOST_NOTIFY) { |
454 | dev_dbg(dev, "Using Host Notify IRQ\n"); | |
72bfcee1 JN |
455 | /* Keep adapter active when Host Notify is required */ |
456 | pm_runtime_get_sync(&client->adapter->dev); | |
331c3425 DT |
457 | irq = i2c_smbus_host_notify_to_irq(client); |
458 | } else if (dev->of_node) { | |
3fffd128 DT |
459 | irq = of_irq_get_byname(dev->of_node, "irq"); |
460 | if (irq == -EINVAL || irq == -ENODATA) | |
461 | irq = of_irq_get(dev->of_node, 0); | |
462 | } else if (ACPI_COMPANION(dev)) { | |
16c9db1d | 463 | irq = i2c_acpi_get_irq(client); |
3fffd128 | 464 | } |
3c3dd56f AV |
465 | if (irq == -EPROBE_DEFER) { |
466 | status = irq; | |
467 | goto put_sync_adapter; | |
468 | } | |
331c3425 | 469 | |
6f34be74 GU |
470 | if (irq < 0) |
471 | irq = 0; | |
2fd36c55 LP |
472 | |
473 | client->irq = irq; | |
474 | } | |
475 | ||
0c2a3493 WS |
476 | driver = to_i2c_driver(dev->driver); |
477 | ||
da10c06a | 478 | /* |
f4b17a14 JMC |
479 | * An I2C ID table is not mandatory, if and only if, a suitable OF |
480 | * or ACPI ID table is supplied for the probing device. | |
da10c06a LJ |
481 | */ |
482 | if (!driver->id_table && | |
e3cb82c6 | 483 | !acpi_driver_match_device(dev, dev->driver) && |
3c3dd56f AV |
484 | !i2c_of_match_device(dev->driver->of_match_table, client)) { |
485 | status = -ENODEV; | |
486 | goto put_sync_adapter; | |
487 | } | |
0acc2b32 | 488 | |
3fffd128 | 489 | if (client->flags & I2C_CLIENT_WAKE) { |
3e99834c | 490 | int wakeirq; |
3fffd128 | 491 | |
3e99834c | 492 | wakeirq = of_irq_get_byname(dev->of_node, "wakeup"); |
3c3dd56f AV |
493 | if (wakeirq == -EPROBE_DEFER) { |
494 | status = wakeirq; | |
495 | goto put_sync_adapter; | |
496 | } | |
3fffd128 DT |
497 | |
498 | device_init_wakeup(&client->dev, true); | |
499 | ||
500 | if (wakeirq > 0 && wakeirq != client->irq) | |
501 | status = dev_pm_set_dedicated_wake_irq(dev, wakeirq); | |
502 | else if (client->irq > 0) | |
c18fba23 | 503 | status = dev_pm_set_wake_irq(dev, client->irq); |
3fffd128 DT |
504 | else |
505 | status = 0; | |
506 | ||
507 | if (status) | |
b93d3d37 | 508 | dev_warn(&client->dev, "failed to set up wakeup irq\n"); |
3fffd128 DT |
509 | } |
510 | ||
7b4fbc50 | 511 | dev_dbg(dev, "probe\n"); |
d2653e92 | 512 | |
86be408b SN |
513 | status = of_clk_set_defaults(dev->of_node, false); |
514 | if (status < 0) | |
3fffd128 | 515 | goto err_clear_wakeup_irq; |
86be408b | 516 | |
e09b0d4e | 517 | status = dev_pm_domain_attach(&client->dev, true); |
e6a20b6c | 518 | if (status) |
74cedd30 KB |
519 | goto err_clear_wakeup_irq; |
520 | ||
b8a1a4cd LJ |
521 | /* |
522 | * When there are no more users of probe(), | |
523 | * rename probe_new to probe. | |
524 | */ | |
525 | if (driver->probe_new) | |
526 | status = driver->probe_new(client); | |
527 | else if (driver->probe) | |
528 | status = driver->probe(client, | |
529 | i2c_match_id(driver->id_table, client)); | |
530 | else | |
531 | status = -EINVAL; | |
532 | ||
74cedd30 KB |
533 | if (status) |
534 | goto err_detach_pm_domain; | |
72fa818e | 535 | |
3fffd128 DT |
536 | return 0; |
537 | ||
538 | err_detach_pm_domain: | |
539 | dev_pm_domain_detach(&client->dev, true); | |
540 | err_clear_wakeup_irq: | |
541 | dev_pm_clear_wake_irq(&client->dev); | |
542 | device_init_wakeup(&client->dev, false); | |
3c3dd56f AV |
543 | put_sync_adapter: |
544 | if (client->flags & I2C_CLIENT_HOST_NOTIFY) | |
545 | pm_runtime_put_sync(&client->adapter->dev); | |
546 | ||
50c3304a | 547 | return status; |
f37dd80a | 548 | } |
1da177e4 | 549 | |
f37dd80a DB |
550 | static int i2c_device_remove(struct device *dev) |
551 | { | |
4e970a0a | 552 | struct i2c_client *client = to_i2c_client(dev); |
a1d9e6e4 | 553 | struct i2c_driver *driver; |
a1d9e6e4 | 554 | |
a1d9e6e4 DB |
555 | driver = to_i2c_driver(dev->driver); |
556 | if (driver->remove) { | |
71637c62 UKK |
557 | int status; |
558 | ||
a1d9e6e4 | 559 | dev_dbg(dev, "remove\n"); |
71637c62 | 560 | |
a1d9e6e4 | 561 | status = driver->remove(client); |
71637c62 UKK |
562 | if (status) |
563 | dev_warn(dev, "remove failed (%pe), will be ignored\n", ERR_PTR(status)); | |
a1d9e6e4 | 564 | } |
72fa818e | 565 | |
e09b0d4e | 566 | dev_pm_domain_detach(&client->dev, true); |
3fffd128 DT |
567 | |
568 | dev_pm_clear_wake_irq(&client->dev); | |
569 | device_init_wakeup(&client->dev, false); | |
570 | ||
6e76cb7d | 571 | client->irq = 0; |
72bfcee1 JN |
572 | if (client->flags & I2C_CLIENT_HOST_NOTIFY) |
573 | pm_runtime_put(&client->adapter->dev); | |
6f108dd7 | 574 | |
71637c62 UKK |
575 | /* return always 0 because there is WIP to make remove-functions void */ |
576 | return 0; | |
1da177e4 LT |
577 | } |
578 | ||
f37dd80a | 579 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 580 | { |
51298d12 | 581 | struct i2c_client *client = i2c_verify_client(dev); |
f37dd80a DB |
582 | struct i2c_driver *driver; |
583 | ||
51298d12 | 584 | if (!client || !dev->driver) |
f37dd80a DB |
585 | return; |
586 | driver = to_i2c_driver(dev->driver); | |
587 | if (driver->shutdown) | |
51298d12 | 588 | driver->shutdown(client); |
1da177e4 LT |
589 | } |
590 | ||
9c1600ed DB |
591 | static void i2c_client_dev_release(struct device *dev) |
592 | { | |
593 | kfree(to_i2c_client(dev)); | |
594 | } | |
595 | ||
09b8ce0a | 596 | static ssize_t |
54a19fd4 | 597 | name_show(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 | 598 | { |
4f8cf824 JD |
599 | return sprintf(buf, "%s\n", dev->type == &i2c_client_type ? |
600 | to_i2c_client(dev)->name : to_i2c_adapter(dev)->name); | |
7b4fbc50 | 601 | } |
54a19fd4 | 602 | static DEVICE_ATTR_RO(name); |
7b4fbc50 | 603 | |
09b8ce0a | 604 | static ssize_t |
54a19fd4 | 605 | modalias_show(struct device *dev, struct device_attribute *attr, char *buf) |
7b4fbc50 DB |
606 | { |
607 | struct i2c_client *client = to_i2c_client(dev); | |
8c4ff6d0 ZR |
608 | int len; |
609 | ||
af503716 JMC |
610 | len = of_device_modalias(dev, buf, PAGE_SIZE); |
611 | if (len != -ENODEV) | |
612 | return len; | |
613 | ||
8c4ff6d0 ZR |
614 | len = acpi_device_modalias(dev, buf, PAGE_SIZE -1); |
615 | if (len != -ENODEV) | |
616 | return len; | |
617 | ||
eb8a7908 | 618 | return sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 | 619 | } |
54a19fd4 | 620 | static DEVICE_ATTR_RO(modalias); |
51298d12 JD |
621 | |
622 | static struct attribute *i2c_dev_attrs[] = { | |
623 | &dev_attr_name.attr, | |
7b4fbc50 | 624 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ |
51298d12 JD |
625 | &dev_attr_modalias.attr, |
626 | NULL | |
627 | }; | |
a5eb71b2 | 628 | ATTRIBUTE_GROUPS(i2c_dev); |
54067ee2 | 629 | |
e9ca9eb9 | 630 | struct bus_type i2c_bus_type = { |
f37dd80a DB |
631 | .name = "i2c", |
632 | .match = i2c_device_match, | |
633 | .probe = i2c_device_probe, | |
634 | .remove = i2c_device_remove, | |
635 | .shutdown = i2c_device_shutdown, | |
b864c7d5 | 636 | }; |
e9ca9eb9 | 637 | EXPORT_SYMBOL_GPL(i2c_bus_type); |
b864c7d5 | 638 | |
00a06c22 | 639 | struct device_type i2c_client_type = { |
a5eb71b2 | 640 | .groups = i2c_dev_groups, |
51298d12 JD |
641 | .uevent = i2c_device_uevent, |
642 | .release = i2c_client_dev_release, | |
643 | }; | |
00a06c22 | 644 | EXPORT_SYMBOL_GPL(i2c_client_type); |
51298d12 | 645 | |
9b766b81 DB |
646 | |
647 | /** | |
648 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
649 | * @dev: device, probably from some driver model iterator | |
650 | * | |
651 | * When traversing the driver model tree, perhaps using driver model | |
652 | * iterators like @device_for_each_child(), you can't assume very much | |
653 | * about the nodes you find. Use this function to avoid oopses caused | |
654 | * by wrongly treating some non-I2C device as an i2c_client. | |
655 | */ | |
656 | struct i2c_client *i2c_verify_client(struct device *dev) | |
657 | { | |
51298d12 | 658 | return (dev->type == &i2c_client_type) |
9b766b81 DB |
659 | ? to_i2c_client(dev) |
660 | : NULL; | |
661 | } | |
662 | EXPORT_SYMBOL(i2c_verify_client); | |
663 | ||
664 | ||
da899f55 WS |
665 | /* Return a unique address which takes the flags of the client into account */ |
666 | static unsigned short i2c_encode_flags_to_addr(struct i2c_client *client) | |
667 | { | |
668 | unsigned short addr = client->addr; | |
669 | ||
670 | /* For some client flags, add an arbitrary offset to avoid collisions */ | |
671 | if (client->flags & I2C_CLIENT_TEN) | |
672 | addr |= I2C_ADDR_OFFSET_TEN_BIT; | |
673 | ||
674 | if (client->flags & I2C_CLIENT_SLAVE) | |
675 | addr |= I2C_ADDR_OFFSET_SLAVE; | |
676 | ||
677 | return addr; | |
678 | } | |
679 | ||
3a89db5f | 680 | /* This is a permissive address validity check, I2C address map constraints |
25985edc | 681 | * are purposely not enforced, except for the general call address. */ |
398432ed | 682 | static int i2c_check_addr_validity(unsigned int addr, unsigned short flags) |
3a89db5f | 683 | { |
c4019b70 | 684 | if (flags & I2C_CLIENT_TEN) { |
3a89db5f | 685 | /* 10-bit address, all values are valid */ |
c4019b70 | 686 | if (addr > 0x3ff) |
3a89db5f JD |
687 | return -EINVAL; |
688 | } else { | |
689 | /* 7-bit address, reject the general call address */ | |
c4019b70 | 690 | if (addr == 0x00 || addr > 0x7f) |
3a89db5f JD |
691 | return -EINVAL; |
692 | } | |
693 | return 0; | |
694 | } | |
695 | ||
656b8761 JD |
696 | /* And this is a strict address validity check, used when probing. If a |
697 | * device uses a reserved address, then it shouldn't be probed. 7-bit | |
698 | * addressing is assumed, 10-bit address devices are rare and should be | |
699 | * explicitly enumerated. */ | |
e4991ecd | 700 | int i2c_check_7bit_addr_validity_strict(unsigned short addr) |
656b8761 JD |
701 | { |
702 | /* | |
703 | * Reserved addresses per I2C specification: | |
704 | * 0x00 General call address / START byte | |
705 | * 0x01 CBUS address | |
706 | * 0x02 Reserved for different bus format | |
707 | * 0x03 Reserved for future purposes | |
708 | * 0x04-0x07 Hs-mode master code | |
709 | * 0x78-0x7b 10-bit slave addressing | |
710 | * 0x7c-0x7f Reserved for future purposes | |
711 | */ | |
712 | if (addr < 0x08 || addr > 0x77) | |
713 | return -EINVAL; | |
714 | return 0; | |
715 | } | |
716 | ||
3b5f794b JD |
717 | static int __i2c_check_addr_busy(struct device *dev, void *addrp) |
718 | { | |
719 | struct i2c_client *client = i2c_verify_client(dev); | |
720 | int addr = *(int *)addrp; | |
721 | ||
9bccc70a | 722 | if (client && i2c_encode_flags_to_addr(client) == addr) |
3b5f794b JD |
723 | return -EBUSY; |
724 | return 0; | |
725 | } | |
726 | ||
0826374b ML |
727 | /* walk up mux tree */ |
728 | static int i2c_check_mux_parents(struct i2c_adapter *adapter, int addr) | |
729 | { | |
97cc4d49 | 730 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
731 | int result; |
732 | ||
733 | result = device_for_each_child(&adapter->dev, &addr, | |
734 | __i2c_check_addr_busy); | |
735 | ||
97cc4d49 JD |
736 | if (!result && parent) |
737 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
738 | |
739 | return result; | |
740 | } | |
741 | ||
742 | /* recurse down mux tree */ | |
743 | static int i2c_check_mux_children(struct device *dev, void *addrp) | |
744 | { | |
745 | int result; | |
746 | ||
747 | if (dev->type == &i2c_adapter_type) | |
748 | result = device_for_each_child(dev, addrp, | |
749 | i2c_check_mux_children); | |
750 | else | |
751 | result = __i2c_check_addr_busy(dev, addrp); | |
752 | ||
753 | return result; | |
754 | } | |
755 | ||
3b5f794b JD |
756 | static int i2c_check_addr_busy(struct i2c_adapter *adapter, int addr) |
757 | { | |
97cc4d49 | 758 | struct i2c_adapter *parent = i2c_parent_is_i2c_adapter(adapter); |
0826374b ML |
759 | int result = 0; |
760 | ||
97cc4d49 JD |
761 | if (parent) |
762 | result = i2c_check_mux_parents(parent, addr); | |
0826374b ML |
763 | |
764 | if (!result) | |
765 | result = device_for_each_child(&adapter->dev, &addr, | |
766 | i2c_check_mux_children); | |
767 | ||
768 | return result; | |
3b5f794b JD |
769 | } |
770 | ||
fe61e07e | 771 | /** |
8320f495 | 772 | * i2c_adapter_lock_bus - Get exclusive access to an I2C bus segment |
fe61e07e | 773 | * @adapter: Target I2C bus segment |
8320f495 PR |
774 | * @flags: I2C_LOCK_ROOT_ADAPTER locks the root i2c adapter, I2C_LOCK_SEGMENT |
775 | * locks only this branch in the adapter tree | |
fe61e07e | 776 | */ |
8320f495 PR |
777 | static void i2c_adapter_lock_bus(struct i2c_adapter *adapter, |
778 | unsigned int flags) | |
fe61e07e | 779 | { |
7b94ea50 | 780 | rt_mutex_lock_nested(&adapter->bus_lock, i2c_adapter_depth(adapter)); |
fe61e07e | 781 | } |
fe61e07e JD |
782 | |
783 | /** | |
8320f495 | 784 | * i2c_adapter_trylock_bus - Try to get exclusive access to an I2C bus segment |
fe61e07e | 785 | * @adapter: Target I2C bus segment |
8320f495 PR |
786 | * @flags: I2C_LOCK_ROOT_ADAPTER trylocks the root i2c adapter, I2C_LOCK_SEGMENT |
787 | * trylocks only this branch in the adapter tree | |
fe61e07e | 788 | */ |
8320f495 PR |
789 | static int i2c_adapter_trylock_bus(struct i2c_adapter *adapter, |
790 | unsigned int flags) | |
fe61e07e | 791 | { |
fa96f0cb | 792 | return rt_mutex_trylock(&adapter->bus_lock); |
fe61e07e JD |
793 | } |
794 | ||
795 | /** | |
8320f495 | 796 | * i2c_adapter_unlock_bus - Release exclusive access to an I2C bus segment |
fe61e07e | 797 | * @adapter: Target I2C bus segment |
8320f495 PR |
798 | * @flags: I2C_LOCK_ROOT_ADAPTER unlocks the root i2c adapter, I2C_LOCK_SEGMENT |
799 | * unlocks only this branch in the adapter tree | |
fe61e07e | 800 | */ |
8320f495 PR |
801 | static void i2c_adapter_unlock_bus(struct i2c_adapter *adapter, |
802 | unsigned int flags) | |
fe61e07e | 803 | { |
fa96f0cb | 804 | rt_mutex_unlock(&adapter->bus_lock); |
fe61e07e | 805 | } |
fe61e07e | 806 | |
70762abb | 807 | static void i2c_dev_set_name(struct i2c_adapter *adap, |
728fe6ce HG |
808 | struct i2c_client *client, |
809 | struct i2c_board_info const *info) | |
70762abb JN |
810 | { |
811 | struct acpi_device *adev = ACPI_COMPANION(&client->dev); | |
812 | ||
728fe6ce HG |
813 | if (info && info->dev_name) { |
814 | dev_set_name(&client->dev, "i2c-%s", info->dev_name); | |
815 | return; | |
816 | } | |
817 | ||
70762abb JN |
818 | if (adev) { |
819 | dev_set_name(&client->dev, "i2c-%s", acpi_dev_name(adev)); | |
820 | return; | |
821 | } | |
822 | ||
70762abb | 823 | dev_set_name(&client->dev, "%d-%04x", i2c_adapter_id(adap), |
da899f55 | 824 | i2c_encode_flags_to_addr(client)); |
70762abb JN |
825 | } |
826 | ||
1d7534b6 CK |
827 | int i2c_dev_irq_from_resources(const struct resource *resources, |
828 | unsigned int num_resources) | |
4124c4eb DT |
829 | { |
830 | struct irq_data *irqd; | |
831 | int i; | |
832 | ||
833 | for (i = 0; i < num_resources; i++) { | |
834 | const struct resource *r = &resources[i]; | |
835 | ||
836 | if (resource_type(r) != IORESOURCE_IRQ) | |
837 | continue; | |
838 | ||
839 | if (r->flags & IORESOURCE_BITS) { | |
840 | irqd = irq_get_irq_data(r->start); | |
841 | if (!irqd) | |
842 | break; | |
843 | ||
844 | irqd_set_trigger_type(irqd, r->flags & IORESOURCE_BITS); | |
845 | } | |
846 | ||
847 | return r->start; | |
848 | } | |
849 | ||
850 | return 0; | |
851 | } | |
852 | ||
9c1600ed | 853 | /** |
7159dbda | 854 | * i2c_new_client_device - instantiate an i2c device |
9c1600ed DB |
855 | * @adap: the adapter managing the device |
856 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 857 | * Context: can sleep |
9c1600ed | 858 | * |
f8a227e8 JD |
859 | * Create an i2c device. Binding is handled through driver model |
860 | * probe()/remove() methods. A driver may be bound to this device when we | |
861 | * return from this function, or any later moment (e.g. maybe hotplugging will | |
862 | * load the driver module). This call is not appropriate for use by mainboard | |
863 | * initialization logic, which usually runs during an arch_initcall() long | |
864 | * before any i2c_adapter could exist. | |
9c1600ed DB |
865 | * |
866 | * This returns the new i2c client, which may be saved for later use with | |
7159dbda | 867 | * i2c_unregister_device(); or an ERR_PTR to describe the error. |
9c1600ed | 868 | */ |
550113d4 | 869 | struct i2c_client * |
7159dbda | 870 | i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info) |
9c1600ed DB |
871 | { |
872 | struct i2c_client *client; | |
873 | int status; | |
874 | ||
875 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
876 | if (!client) | |
7159dbda | 877 | return ERR_PTR(-ENOMEM); |
9c1600ed DB |
878 | |
879 | client->adapter = adap; | |
880 | ||
881 | client->dev.platform_data = info->platform_data; | |
ee35425c | 882 | client->flags = info->flags; |
9c1600ed | 883 | client->addr = info->addr; |
4124c4eb | 884 | |
93b6604c JB |
885 | client->init_irq = info->irq; |
886 | if (!client->init_irq) | |
887 | client->init_irq = i2c_dev_irq_from_resources(info->resources, | |
4124c4eb | 888 | info->num_resources); |
9c1600ed | 889 | |
9c1600ed DB |
890 | strlcpy(client->name, info->type, sizeof(client->name)); |
891 | ||
c4019b70 | 892 | status = i2c_check_addr_validity(client->addr, client->flags); |
3a89db5f JD |
893 | if (status) { |
894 | dev_err(&adap->dev, "Invalid %d-bit I2C address 0x%02hx\n", | |
895 | client->flags & I2C_CLIENT_TEN ? 10 : 7, client->addr); | |
896 | goto out_err_silent; | |
897 | } | |
898 | ||
f8a227e8 | 899 | /* Check for address business */ |
9bccc70a | 900 | status = i2c_check_addr_busy(adap, i2c_encode_flags_to_addr(client)); |
f8a227e8 JD |
901 | if (status) |
902 | goto out_err; | |
903 | ||
904 | client->dev.parent = &client->adapter->dev; | |
905 | client->dev.bus = &i2c_bus_type; | |
51298d12 | 906 | client->dev.type = &i2c_client_type; |
04782265 | 907 | client->dev.of_node = of_node_get(info->of_node); |
ce793486 | 908 | client->dev.fwnode = info->fwnode; |
f8a227e8 | 909 | |
728fe6ce | 910 | i2c_dev_set_name(adap, client, info); |
d3e1b617 DT |
911 | |
912 | if (info->properties) { | |
913 | status = device_add_properties(&client->dev, info->properties); | |
914 | if (status) { | |
915 | dev_err(&adap->dev, | |
916 | "Failed to add properties to client %s: %d\n", | |
917 | client->name, status); | |
04782265 | 918 | goto out_err_put_of_node; |
d3e1b617 DT |
919 | } |
920 | } | |
921 | ||
f8a227e8 JD |
922 | status = device_register(&client->dev); |
923 | if (status) | |
d3e1b617 | 924 | goto out_free_props; |
f8a227e8 | 925 | |
f8a227e8 JD |
926 | dev_dbg(&adap->dev, "client [%s] registered with bus id %s\n", |
927 | client->name, dev_name(&client->dev)); | |
928 | ||
9c1600ed | 929 | return client; |
f8a227e8 | 930 | |
d3e1b617 DT |
931 | out_free_props: |
932 | if (info->properties) | |
933 | device_remove_properties(&client->dev); | |
04782265 BB |
934 | out_err_put_of_node: |
935 | of_node_put(info->of_node); | |
f8a227e8 | 936 | out_err: |
b93d3d37 AS |
937 | dev_err(&adap->dev, |
938 | "Failed to register i2c client %s at 0x%02x (%d)\n", | |
939 | client->name, client->addr, status); | |
3a89db5f | 940 | out_err_silent: |
f8a227e8 | 941 | kfree(client); |
7159dbda HK |
942 | return ERR_PTR(status); |
943 | } | |
944 | EXPORT_SYMBOL_GPL(i2c_new_client_device); | |
945 | ||
9c1600ed | 946 | /** |
87e07437 WS |
947 | * i2c_unregister_device - reverse effect of i2c_new_*_device() |
948 | * @client: value returned from i2c_new_*_device() | |
d64f73be | 949 | * Context: can sleep |
9c1600ed DB |
950 | */ |
951 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 | 952 | { |
689f5358 | 953 | if (IS_ERR_OR_NULL(client)) |
7b43dd19 | 954 | return; |
e0638fa4 LW |
955 | |
956 | if (client->dev.of_node) { | |
4f001fd3 | 957 | of_node_clear_flag(client->dev.of_node, OF_POPULATED); |
e0638fa4 LW |
958 | of_node_put(client->dev.of_node); |
959 | } | |
960 | ||
525e6fab OP |
961 | if (ACPI_COMPANION(&client->dev)) |
962 | acpi_device_clear_enumerated(ACPI_COMPANION(&client->dev)); | |
a1d9e6e4 DB |
963 | device_unregister(&client->dev); |
964 | } | |
9c1600ed | 965 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
966 | |
967 | ||
60b129d7 JD |
968 | static const struct i2c_device_id dummy_id[] = { |
969 | { "dummy", 0 }, | |
970 | { }, | |
971 | }; | |
972 | ||
d2653e92 JD |
973 | static int dummy_probe(struct i2c_client *client, |
974 | const struct i2c_device_id *id) | |
975 | { | |
976 | return 0; | |
977 | } | |
978 | ||
979 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
980 | { |
981 | return 0; | |
982 | } | |
983 | ||
984 | static struct i2c_driver dummy_driver = { | |
985 | .driver.name = "dummy", | |
d2653e92 JD |
986 | .probe = dummy_probe, |
987 | .remove = dummy_remove, | |
60b129d7 | 988 | .id_table = dummy_id, |
e9f1373b DB |
989 | }; |
990 | ||
991 | /** | |
7159dbda | 992 | * i2c_new_dummy_device - return a new i2c device bound to a dummy driver |
e9f1373b DB |
993 | * @adapter: the adapter managing the device |
994 | * @address: seven bit address to be used | |
e9f1373b DB |
995 | * Context: can sleep |
996 | * | |
997 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
998 | * with devices that consume multiple addresses. Examples of such chips | |
999 | * include various EEPROMS (like 24c04 and 24c08 models). | |
1000 | * | |
1001 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
1002 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
1003 | * And second, this prevents the specified address from being bound to a | |
1004 | * different driver. | |
1005 | * | |
1006 | * This returns the new i2c client, which should be saved for later use with | |
7159dbda | 1007 | * i2c_unregister_device(); or an ERR_PTR to describe the error. |
e9f1373b | 1008 | */ |
550113d4 | 1009 | struct i2c_client *i2c_new_dummy_device(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
1010 | { |
1011 | struct i2c_board_info info = { | |
60b129d7 | 1012 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
1013 | }; |
1014 | ||
7159dbda HK |
1015 | return i2c_new_client_device(adapter, &info); |
1016 | } | |
1017 | EXPORT_SYMBOL_GPL(i2c_new_dummy_device); | |
1018 | ||
b8f5fe3b HK |
1019 | struct i2c_dummy_devres { |
1020 | struct i2c_client *client; | |
1021 | }; | |
1022 | ||
1023 | static void devm_i2c_release_dummy(struct device *dev, void *res) | |
1024 | { | |
1025 | struct i2c_dummy_devres *this = res; | |
1026 | ||
1027 | i2c_unregister_device(this->client); | |
1028 | } | |
1029 | ||
1030 | /** | |
1031 | * devm_i2c_new_dummy_device - return a new i2c device bound to a dummy driver | |
1032 | * @dev: device the managed resource is bound to | |
1033 | * @adapter: the adapter managing the device | |
1034 | * @address: seven bit address to be used | |
1035 | * Context: can sleep | |
1036 | * | |
1037 | * This is the device-managed version of @i2c_new_dummy_device. It returns the | |
1038 | * new i2c client or an ERR_PTR in case of an error. | |
1039 | */ | |
1040 | struct i2c_client *devm_i2c_new_dummy_device(struct device *dev, | |
1041 | struct i2c_adapter *adapter, | |
1042 | u16 address) | |
1043 | { | |
1044 | struct i2c_dummy_devres *dr; | |
1045 | struct i2c_client *client; | |
1046 | ||
1047 | dr = devres_alloc(devm_i2c_release_dummy, sizeof(*dr), GFP_KERNEL); | |
1048 | if (!dr) | |
1049 | return ERR_PTR(-ENOMEM); | |
1050 | ||
1051 | client = i2c_new_dummy_device(adapter, address); | |
1052 | if (IS_ERR(client)) { | |
1053 | devres_free(dr); | |
1054 | } else { | |
1055 | dr->client = client; | |
1056 | devres_add(dev, dr); | |
1057 | } | |
1058 | ||
1059 | return client; | |
1060 | } | |
1061 | EXPORT_SYMBOL_GPL(devm_i2c_new_dummy_device); | |
1062 | ||
0f614d83 | 1063 | /** |
af80559b | 1064 | * i2c_new_ancillary_device - Helper to get the instantiated secondary address |
0f614d83 JMH |
1065 | * and create the associated device |
1066 | * @client: Handle to the primary client | |
1067 | * @name: Handle to specify which secondary address to get | |
1068 | * @default_addr: Used as a fallback if no secondary address was specified | |
1069 | * Context: can sleep | |
1070 | * | |
1071 | * I2C clients can be composed of multiple I2C slaves bound together in a single | |
1072 | * component. The I2C client driver then binds to the master I2C slave and needs | |
1073 | * to create I2C dummy clients to communicate with all the other slaves. | |
1074 | * | |
1075 | * This function creates and returns an I2C dummy client whose I2C address is | |
1076 | * retrieved from the platform firmware based on the given slave name. If no | |
1077 | * address is specified by the firmware default_addr is used. | |
1078 | * | |
1079 | * On DT-based platforms the address is retrieved from the "reg" property entry | |
1080 | * cell whose "reg-names" value matches the slave name. | |
1081 | * | |
1082 | * This returns the new i2c client, which should be saved for later use with | |
af80559b | 1083 | * i2c_unregister_device(); or an ERR_PTR to describe the error. |
0f614d83 | 1084 | */ |
af80559b | 1085 | struct i2c_client *i2c_new_ancillary_device(struct i2c_client *client, |
0f614d83 JMH |
1086 | const char *name, |
1087 | u16 default_addr) | |
1088 | { | |
1089 | struct device_node *np = client->dev.of_node; | |
1090 | u32 addr = default_addr; | |
1091 | int i; | |
1092 | ||
1093 | if (np) { | |
1094 | i = of_property_match_string(np, "reg-names", name); | |
1095 | if (i >= 0) | |
1096 | of_property_read_u32_index(np, "reg", i, &addr); | |
1097 | } | |
1098 | ||
1099 | dev_dbg(&client->adapter->dev, "Address for %s : 0x%x\n", name, addr); | |
af80559b | 1100 | return i2c_new_dummy_device(client->adapter, addr); |
0f614d83 | 1101 | } |
af80559b | 1102 | EXPORT_SYMBOL_GPL(i2c_new_ancillary_device); |
0f614d83 | 1103 | |
f37dd80a DB |
1104 | /* ------------------------------------------------------------------------- */ |
1105 | ||
16ffadfc DB |
1106 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
1107 | ||
83eaaed0 | 1108 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 1109 | { |
ef2c8321 | 1110 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
1111 | complete(&adap->dev_released); |
1112 | } | |
1113 | ||
8dd1fe15 | 1114 | unsigned int i2c_adapter_depth(struct i2c_adapter *adapter) |
390946b1 JD |
1115 | { |
1116 | unsigned int depth = 0; | |
1117 | ||
1118 | while ((adapter = i2c_parent_is_i2c_adapter(adapter))) | |
1119 | depth++; | |
1120 | ||
2771dc34 BG |
1121 | WARN_ONCE(depth >= MAX_LOCKDEP_SUBCLASSES, |
1122 | "adapter depth exceeds lockdep subclass limit\n"); | |
1123 | ||
390946b1 JD |
1124 | return depth; |
1125 | } | |
8dd1fe15 | 1126 | EXPORT_SYMBOL_GPL(i2c_adapter_depth); |
390946b1 | 1127 | |
99cd8e25 JD |
1128 | /* |
1129 | * Let users instantiate I2C devices through sysfs. This can be used when | |
1130 | * platform initialization code doesn't contain the proper data for | |
1131 | * whatever reason. Also useful for drivers that do device detection and | |
1132 | * detection fails, either because the device uses an unexpected address, | |
1133 | * or this is a compatible device with different ID register values. | |
1134 | * | |
1135 | * Parameter checking may look overzealous, but we really don't want | |
1136 | * the user to provide incorrect parameters. | |
1137 | */ | |
1138 | static ssize_t | |
54a19fd4 GU |
1139 | new_device_store(struct device *dev, struct device_attribute *attr, |
1140 | const char *buf, size_t count) | |
99cd8e25 JD |
1141 | { |
1142 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1143 | struct i2c_board_info info; | |
1144 | struct i2c_client *client; | |
1145 | char *blank, end; | |
1146 | int res; | |
1147 | ||
99cd8e25 JD |
1148 | memset(&info, 0, sizeof(struct i2c_board_info)); |
1149 | ||
1150 | blank = strchr(buf, ' '); | |
1151 | if (!blank) { | |
1152 | dev_err(dev, "%s: Missing parameters\n", "new_device"); | |
1153 | return -EINVAL; | |
1154 | } | |
1155 | if (blank - buf > I2C_NAME_SIZE - 1) { | |
1156 | dev_err(dev, "%s: Invalid device name\n", "new_device"); | |
1157 | return -EINVAL; | |
1158 | } | |
1159 | memcpy(info.type, buf, blank - buf); | |
1160 | ||
1161 | /* Parse remaining parameters, reject extra parameters */ | |
1162 | res = sscanf(++blank, "%hi%c", &info.addr, &end); | |
1163 | if (res < 1) { | |
1164 | dev_err(dev, "%s: Can't parse I2C address\n", "new_device"); | |
1165 | return -EINVAL; | |
1166 | } | |
1167 | if (res > 1 && end != '\n') { | |
1168 | dev_err(dev, "%s: Extra parameters\n", "new_device"); | |
1169 | return -EINVAL; | |
1170 | } | |
1171 | ||
cfa0327b WS |
1172 | if ((info.addr & I2C_ADDR_OFFSET_TEN_BIT) == I2C_ADDR_OFFSET_TEN_BIT) { |
1173 | info.addr &= ~I2C_ADDR_OFFSET_TEN_BIT; | |
1174 | info.flags |= I2C_CLIENT_TEN; | |
1175 | } | |
1176 | ||
1177 | if (info.addr & I2C_ADDR_OFFSET_SLAVE) { | |
1178 | info.addr &= ~I2C_ADDR_OFFSET_SLAVE; | |
1179 | info.flags |= I2C_CLIENT_SLAVE; | |
1180 | } | |
1181 | ||
7159dbda HK |
1182 | client = i2c_new_client_device(adap, &info); |
1183 | if (IS_ERR(client)) | |
1184 | return PTR_ERR(client); | |
99cd8e25 JD |
1185 | |
1186 | /* Keep track of the added device */ | |
dafc50d1 | 1187 | mutex_lock(&adap->userspace_clients_lock); |
6629dcff | 1188 | list_add_tail(&client->detected, &adap->userspace_clients); |
dafc50d1 | 1189 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1190 | dev_info(dev, "%s: Instantiated device %s at 0x%02hx\n", "new_device", |
1191 | info.type, info.addr); | |
1192 | ||
1193 | return count; | |
1194 | } | |
54a19fd4 | 1195 | static DEVICE_ATTR_WO(new_device); |
99cd8e25 JD |
1196 | |
1197 | /* | |
1198 | * And of course let the users delete the devices they instantiated, if | |
1199 | * they got it wrong. This interface can only be used to delete devices | |
1200 | * instantiated by i2c_sysfs_new_device above. This guarantees that we | |
1201 | * don't delete devices to which some kernel code still has references. | |
1202 | * | |
1203 | * Parameter checking may look overzealous, but we really don't want | |
1204 | * the user to delete the wrong device. | |
1205 | */ | |
1206 | static ssize_t | |
54a19fd4 GU |
1207 | delete_device_store(struct device *dev, struct device_attribute *attr, |
1208 | const char *buf, size_t count) | |
99cd8e25 JD |
1209 | { |
1210 | struct i2c_adapter *adap = to_i2c_adapter(dev); | |
1211 | struct i2c_client *client, *next; | |
1212 | unsigned short addr; | |
1213 | char end; | |
1214 | int res; | |
1215 | ||
1216 | /* Parse parameters, reject extra parameters */ | |
1217 | res = sscanf(buf, "%hi%c", &addr, &end); | |
1218 | if (res < 1) { | |
1219 | dev_err(dev, "%s: Can't parse I2C address\n", "delete_device"); | |
1220 | return -EINVAL; | |
1221 | } | |
1222 | if (res > 1 && end != '\n') { | |
1223 | dev_err(dev, "%s: Extra parameters\n", "delete_device"); | |
1224 | return -EINVAL; | |
1225 | } | |
1226 | ||
1227 | /* Make sure the device was added through sysfs */ | |
1228 | res = -ENOENT; | |
390946b1 JD |
1229 | mutex_lock_nested(&adap->userspace_clients_lock, |
1230 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1231 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1232 | detected) { | |
cfa0327b | 1233 | if (i2c_encode_flags_to_addr(client) == addr) { |
99cd8e25 JD |
1234 | dev_info(dev, "%s: Deleting device %s at 0x%02hx\n", |
1235 | "delete_device", client->name, client->addr); | |
1236 | ||
1237 | list_del(&client->detected); | |
1238 | i2c_unregister_device(client); | |
1239 | res = count; | |
1240 | break; | |
1241 | } | |
1242 | } | |
dafc50d1 | 1243 | mutex_unlock(&adap->userspace_clients_lock); |
99cd8e25 JD |
1244 | |
1245 | if (res < 0) | |
1246 | dev_err(dev, "%s: Can't find device in list\n", | |
1247 | "delete_device"); | |
1248 | return res; | |
1249 | } | |
e9b526fe | 1250 | static DEVICE_ATTR_IGNORE_LOCKDEP(delete_device, S_IWUSR, NULL, |
54a19fd4 | 1251 | delete_device_store); |
4f8cf824 JD |
1252 | |
1253 | static struct attribute *i2c_adapter_attrs[] = { | |
1254 | &dev_attr_name.attr, | |
1255 | &dev_attr_new_device.attr, | |
1256 | &dev_attr_delete_device.attr, | |
1257 | NULL | |
1258 | }; | |
a5eb71b2 | 1259 | ATTRIBUTE_GROUPS(i2c_adapter); |
b119dc3f | 1260 | |
0826374b | 1261 | struct device_type i2c_adapter_type = { |
a5eb71b2 | 1262 | .groups = i2c_adapter_groups, |
4f8cf824 | 1263 | .release = i2c_adapter_dev_release, |
1da177e4 | 1264 | }; |
0826374b | 1265 | EXPORT_SYMBOL_GPL(i2c_adapter_type); |
1da177e4 | 1266 | |
643dd09e SW |
1267 | /** |
1268 | * i2c_verify_adapter - return parameter as i2c_adapter or NULL | |
1269 | * @dev: device, probably from some driver model iterator | |
1270 | * | |
1271 | * When traversing the driver model tree, perhaps using driver model | |
1272 | * iterators like @device_for_each_child(), you can't assume very much | |
1273 | * about the nodes you find. Use this function to avoid oopses caused | |
1274 | * by wrongly treating some non-I2C device as an i2c_adapter. | |
1275 | */ | |
1276 | struct i2c_adapter *i2c_verify_adapter(struct device *dev) | |
1277 | { | |
1278 | return (dev->type == &i2c_adapter_type) | |
1279 | ? to_i2c_adapter(dev) | |
1280 | : NULL; | |
1281 | } | |
1282 | EXPORT_SYMBOL(i2c_verify_adapter); | |
1283 | ||
2bb5095a JD |
1284 | #ifdef CONFIG_I2C_COMPAT |
1285 | static struct class_compat *i2c_adapter_compat_class; | |
1286 | #endif | |
1287 | ||
9c1600ed DB |
1288 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
1289 | { | |
1290 | struct i2c_devinfo *devinfo; | |
1291 | ||
f18c41da | 1292 | down_read(&__i2c_board_lock); |
9c1600ed | 1293 | list_for_each_entry(devinfo, &__i2c_board_list, list) { |
87e07437 WS |
1294 | if (devinfo->busnum == adapter->nr && |
1295 | IS_ERR(i2c_new_client_device(adapter, &devinfo->board_info))) | |
09b8ce0a ZX |
1296 | dev_err(&adapter->dev, |
1297 | "Can't create device at 0x%02x\n", | |
9c1600ed DB |
1298 | devinfo->board_info.addr); |
1299 | } | |
f18c41da | 1300 | up_read(&__i2c_board_lock); |
9c1600ed DB |
1301 | } |
1302 | ||
69b0089a JD |
1303 | static int i2c_do_add_adapter(struct i2c_driver *driver, |
1304 | struct i2c_adapter *adap) | |
026526f5 | 1305 | { |
4735c98f JD |
1306 | /* Detect supported devices on that bus, and instantiate them */ |
1307 | i2c_detect(adap, driver); | |
1308 | ||
026526f5 JD |
1309 | return 0; |
1310 | } | |
1311 | ||
69b0089a JD |
1312 | static int __process_new_adapter(struct device_driver *d, void *data) |
1313 | { | |
1314 | return i2c_do_add_adapter(to_i2c_driver(d), data); | |
1315 | } | |
1316 | ||
d1ed7985 PR |
1317 | static const struct i2c_lock_operations i2c_adapter_lock_ops = { |
1318 | .lock_bus = i2c_adapter_lock_bus, | |
1319 | .trylock_bus = i2c_adapter_trylock_bus, | |
1320 | .unlock_bus = i2c_adapter_unlock_bus, | |
1321 | }; | |
1322 | ||
4d5538f5 BT |
1323 | static void i2c_host_notify_irq_teardown(struct i2c_adapter *adap) |
1324 | { | |
1325 | struct irq_domain *domain = adap->host_notify_domain; | |
1326 | irq_hw_number_t hwirq; | |
1327 | ||
1328 | if (!domain) | |
1329 | return; | |
1330 | ||
1331 | for (hwirq = 0 ; hwirq < I2C_ADDR_7BITS_COUNT ; hwirq++) | |
1332 | irq_dispose_mapping(irq_find_mapping(domain, hwirq)); | |
1333 | ||
1334 | irq_domain_remove(domain); | |
1335 | adap->host_notify_domain = NULL; | |
1336 | } | |
1337 | ||
1338 | static int i2c_host_notify_irq_map(struct irq_domain *h, | |
1339 | unsigned int virq, | |
1340 | irq_hw_number_t hw_irq_num) | |
1341 | { | |
1342 | irq_set_chip_and_handler(virq, &dummy_irq_chip, handle_simple_irq); | |
1343 | ||
1344 | return 0; | |
1345 | } | |
1346 | ||
1347 | static const struct irq_domain_ops i2c_host_notify_irq_ops = { | |
1348 | .map = i2c_host_notify_irq_map, | |
1349 | }; | |
1350 | ||
1351 | static int i2c_setup_host_notify_irq_domain(struct i2c_adapter *adap) | |
1352 | { | |
1353 | struct irq_domain *domain; | |
1354 | ||
1355 | if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_HOST_NOTIFY)) | |
1356 | return 0; | |
1357 | ||
8682dc12 | 1358 | domain = irq_domain_create_linear(adap->dev.parent->fwnode, |
4d5538f5 BT |
1359 | I2C_ADDR_7BITS_COUNT, |
1360 | &i2c_host_notify_irq_ops, adap); | |
1361 | if (!domain) | |
1362 | return -ENOMEM; | |
1363 | ||
1364 | adap->host_notify_domain = domain; | |
1365 | ||
1366 | return 0; | |
1367 | } | |
1368 | ||
1369 | /** | |
1370 | * i2c_handle_smbus_host_notify - Forward a Host Notify event to the correct | |
1371 | * I2C client. | |
1372 | * @adap: the adapter | |
1373 | * @addr: the I2C address of the notifying device | |
1374 | * Context: can't sleep | |
1375 | * | |
1376 | * Helper function to be called from an I2C bus driver's interrupt | |
1377 | * handler. It will schedule the Host Notify IRQ. | |
1378 | */ | |
1379 | int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr) | |
1380 | { | |
1381 | int irq; | |
1382 | ||
1383 | if (!adap) | |
1384 | return -EINVAL; | |
1385 | ||
1386 | irq = irq_find_mapping(adap->host_notify_domain, addr); | |
1387 | if (irq <= 0) | |
1388 | return -ENXIO; | |
1389 | ||
1390 | generic_handle_irq(irq); | |
1391 | ||
1392 | return 0; | |
1393 | } | |
1394 | EXPORT_SYMBOL_GPL(i2c_handle_smbus_host_notify); | |
1395 | ||
6e13e641 | 1396 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 1397 | { |
ce0dffaf | 1398 | int res = -EINVAL; |
1da177e4 | 1399 | |
1d0b19c9 | 1400 | /* Can't register until after driver model init */ |
95026658 | 1401 | if (WARN_ON(!is_registered)) { |
35fc37f8 JD |
1402 | res = -EAGAIN; |
1403 | goto out_list; | |
1404 | } | |
1d0b19c9 | 1405 | |
2236baa7 | 1406 | /* Sanity checks */ |
8ddfe410 | 1407 | if (WARN(!adap->name[0], "i2c adapter has no name")) |
ce0dffaf | 1408 | goto out_list; |
8ddfe410 WS |
1409 | |
1410 | if (!adap->algo) { | |
44239a5a | 1411 | pr_err("adapter '%s': no algo supplied!\n", adap->name); |
ce0dffaf | 1412 | goto out_list; |
2236baa7 JD |
1413 | } |
1414 | ||
d1ed7985 PR |
1415 | if (!adap->lock_ops) |
1416 | adap->lock_ops = &i2c_adapter_lock_ops; | |
8320f495 | 1417 | |
9ac6cb5f | 1418 | adap->locked_flags = 0; |
194684e5 | 1419 | rt_mutex_init(&adap->bus_lock); |
6ef91fcc | 1420 | rt_mutex_init(&adap->mux_lock); |
dafc50d1 | 1421 | mutex_init(&adap->userspace_clients_lock); |
6629dcff | 1422 | INIT_LIST_HEAD(&adap->userspace_clients); |
1da177e4 | 1423 | |
8fcfef6e JD |
1424 | /* Set default timeout to 1 second if not already set */ |
1425 | if (adap->timeout == 0) | |
1426 | adap->timeout = HZ; | |
1427 | ||
4d5538f5 BT |
1428 | /* register soft irqs for Host Notify */ |
1429 | res = i2c_setup_host_notify_irq_domain(adap); | |
1430 | if (res) { | |
1431 | pr_err("adapter '%s': can't create Host Notify IRQs (%d)\n", | |
1432 | adap->name, res); | |
1433 | goto out_list; | |
1434 | } | |
1435 | ||
27d9c183 | 1436 | dev_set_name(&adap->dev, "i2c-%d", adap->nr); |
4f8cf824 JD |
1437 | adap->dev.bus = &i2c_bus_type; |
1438 | adap->dev.type = &i2c_adapter_type; | |
b119c6c9 | 1439 | res = device_register(&adap->dev); |
8ddfe410 | 1440 | if (res) { |
44239a5a | 1441 | pr_err("adapter '%s': can't register device (%d)\n", adap->name, res); |
b119c6c9 | 1442 | goto out_list; |
8ddfe410 | 1443 | } |
1da177e4 | 1444 | |
f8756c67 PR |
1445 | res = of_i2c_setup_smbus_alert(adap); |
1446 | if (res) | |
1447 | goto out_reg; | |
1448 | ||
6ada5c1e | 1449 | pm_runtime_no_callbacks(&adap->dev); |
04f59143 | 1450 | pm_suspend_ignore_children(&adap->dev, true); |
9f924169 | 1451 | pm_runtime_enable(&adap->dev); |
6ada5c1e | 1452 | |
23a698fe CC |
1453 | res = i2c_init_recovery(adap); |
1454 | if (res == -EPROBE_DEFER) | |
1455 | goto out_reg; | |
1456 | ||
1457 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); | |
1458 | ||
2bb5095a JD |
1459 | #ifdef CONFIG_I2C_COMPAT |
1460 | res = class_compat_create_link(i2c_adapter_compat_class, &adap->dev, | |
1461 | adap->dev.parent); | |
1462 | if (res) | |
1463 | dev_warn(&adap->dev, | |
1464 | "Failed to create compatibility class link\n"); | |
1465 | #endif | |
1466 | ||
729d6dd5 | 1467 | /* create pre-declared device nodes */ |
687b81d0 | 1468 | of_i2c_register_devices(adap); |
aec809fc | 1469 | i2c_acpi_install_space_handler(adap); |
21653a41 | 1470 | i2c_acpi_register_devices(adap); |
687b81d0 | 1471 | |
6e13e641 DB |
1472 | if (adap->nr < __i2c_first_dynamic_bus_num) |
1473 | i2c_scan_static_board_info(adap); | |
1474 | ||
4735c98f | 1475 | /* Notify drivers */ |
35fc37f8 | 1476 | mutex_lock(&core_lock); |
d6703281 | 1477 | bus_for_each_drv(&i2c_bus_type, NULL, adap, __process_new_adapter); |
caada32a | 1478 | mutex_unlock(&core_lock); |
35fc37f8 JD |
1479 | |
1480 | return 0; | |
b119c6c9 | 1481 | |
f8756c67 PR |
1482 | out_reg: |
1483 | init_completion(&adap->dev_released); | |
1484 | device_unregister(&adap->dev); | |
1485 | wait_for_completion(&adap->dev_released); | |
b119c6c9 | 1486 | out_list: |
35fc37f8 | 1487 | mutex_lock(&core_lock); |
b119c6c9 | 1488 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 JD |
1489 | mutex_unlock(&core_lock); |
1490 | return res; | |
1da177e4 LT |
1491 | } |
1492 | ||
ee5c2744 DA |
1493 | /** |
1494 | * __i2c_add_numbered_adapter - i2c_add_numbered_adapter where nr is never -1 | |
1495 | * @adap: the adapter to register (with adap->nr initialized) | |
1496 | * Context: can sleep | |
1497 | * | |
1498 | * See i2c_add_numbered_adapter() for details. | |
1499 | */ | |
1500 | static int __i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1501 | { | |
84d0b617 | 1502 | int id; |
ee5c2744 DA |
1503 | |
1504 | mutex_lock(&core_lock); | |
84d0b617 | 1505 | id = idr_alloc(&i2c_adapter_idr, adap, adap->nr, adap->nr + 1, GFP_KERNEL); |
ee5c2744 | 1506 | mutex_unlock(&core_lock); |
84d0b617 | 1507 | if (WARN(id < 0, "couldn't get idr")) |
ee5c2744 DA |
1508 | return id == -ENOSPC ? -EBUSY : id; |
1509 | ||
1510 | return i2c_register_adapter(adap); | |
1511 | } | |
1512 | ||
6e13e641 DB |
1513 | /** |
1514 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
1515 | * @adapter: the adapter to add | |
d64f73be | 1516 | * Context: can sleep |
6e13e641 DB |
1517 | * |
1518 | * This routine is used to declare an I2C adapter when its bus number | |
ee5c2744 DA |
1519 | * doesn't matter or when its bus number is specified by an dt alias. |
1520 | * Examples of bases when the bus number doesn't matter: I2C adapters | |
1521 | * dynamically added by USB links or PCI plugin cards. | |
6e13e641 DB |
1522 | * |
1523 | * When this returns zero, a new bus number was allocated and stored | |
1524 | * in adap->nr, and the specified adapter became available for clients. | |
1525 | * Otherwise, a negative errno value is returned. | |
1526 | */ | |
1527 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
1528 | { | |
ee5c2744 | 1529 | struct device *dev = &adapter->dev; |
4ae42b0f | 1530 | int id; |
6e13e641 | 1531 | |
ee5c2744 DA |
1532 | if (dev->of_node) { |
1533 | id = of_alias_get_id(dev->of_node, "i2c"); | |
1534 | if (id >= 0) { | |
1535 | adapter->nr = id; | |
1536 | return __i2c_add_numbered_adapter(adapter); | |
1537 | } | |
1538 | } | |
1539 | ||
caada32a | 1540 | mutex_lock(&core_lock); |
4ae42b0f TH |
1541 | id = idr_alloc(&i2c_adapter_idr, adapter, |
1542 | __i2c_first_dynamic_bus_num, 0, GFP_KERNEL); | |
caada32a | 1543 | mutex_unlock(&core_lock); |
84d0b617 | 1544 | if (WARN(id < 0, "couldn't get idr")) |
4ae42b0f | 1545 | return id; |
6e13e641 DB |
1546 | |
1547 | adapter->nr = id; | |
4ae42b0f | 1548 | |
6e13e641 DB |
1549 | return i2c_register_adapter(adapter); |
1550 | } | |
1551 | EXPORT_SYMBOL(i2c_add_adapter); | |
1552 | ||
1553 | /** | |
1554 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
1555 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 1556 | * Context: can sleep |
6e13e641 DB |
1557 | * |
1558 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
1559 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
1560 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
1561 | * is used to properly configure I2C devices. |
1562 | * | |
488bf314 GL |
1563 | * If the requested bus number is set to -1, then this function will behave |
1564 | * identically to i2c_add_adapter, and will dynamically assign a bus number. | |
1565 | * | |
6e13e641 DB |
1566 | * If no devices have pre-been declared for this bus, then be sure to |
1567 | * register the adapter before any dynamically allocated ones. Otherwise | |
1568 | * the required bus ID may not be available. | |
1569 | * | |
1570 | * When this returns zero, the specified adapter became available for | |
1571 | * clients using the bus number provided in adap->nr. Also, the table | |
1572 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
1573 | * and the appropriate driver model device nodes are created. Otherwise, a | |
1574 | * negative errno value is returned. | |
1575 | */ | |
1576 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
1577 | { | |
488bf314 GL |
1578 | if (adap->nr == -1) /* -1 means dynamically assign bus id */ |
1579 | return i2c_add_adapter(adap); | |
6e13e641 | 1580 | |
ee5c2744 | 1581 | return __i2c_add_numbered_adapter(adap); |
6e13e641 DB |
1582 | } |
1583 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
1584 | ||
19baba4c | 1585 | static void i2c_do_del_adapter(struct i2c_driver *driver, |
69b0089a | 1586 | struct i2c_adapter *adapter) |
026526f5 | 1587 | { |
4735c98f | 1588 | struct i2c_client *client, *_n; |
026526f5 | 1589 | |
acec211c JD |
1590 | /* Remove the devices we created ourselves as the result of hardware |
1591 | * probing (using a driver's detect method) */ | |
4735c98f JD |
1592 | list_for_each_entry_safe(client, _n, &driver->clients, detected) { |
1593 | if (client->adapter == adapter) { | |
1594 | dev_dbg(&adapter->dev, "Removing %s at 0x%x\n", | |
1595 | client->name, client->addr); | |
1596 | list_del(&client->detected); | |
1597 | i2c_unregister_device(client); | |
1598 | } | |
1599 | } | |
026526f5 JD |
1600 | } |
1601 | ||
e549c2b5 | 1602 | static int __unregister_client(struct device *dev, void *dummy) |
5219bf88 JD |
1603 | { |
1604 | struct i2c_client *client = i2c_verify_client(dev); | |
1605 | if (client && strcmp(client->name, "dummy")) | |
1606 | i2c_unregister_device(client); | |
1607 | return 0; | |
1608 | } | |
1609 | ||
1610 | static int __unregister_dummy(struct device *dev, void *dummy) | |
e549c2b5 JD |
1611 | { |
1612 | struct i2c_client *client = i2c_verify_client(dev); | |
7b43dd19 | 1613 | i2c_unregister_device(client); |
e549c2b5 JD |
1614 | return 0; |
1615 | } | |
1616 | ||
69b0089a JD |
1617 | static int __process_removed_adapter(struct device_driver *d, void *data) |
1618 | { | |
19baba4c LPC |
1619 | i2c_do_del_adapter(to_i2c_driver(d), data); |
1620 | return 0; | |
69b0089a JD |
1621 | } |
1622 | ||
d64f73be DB |
1623 | /** |
1624 | * i2c_del_adapter - unregister I2C adapter | |
1625 | * @adap: the adapter being unregistered | |
1626 | * Context: can sleep | |
1627 | * | |
1628 | * This unregisters an I2C adapter which was previously registered | |
1629 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
1630 | */ | |
71546300 | 1631 | void i2c_del_adapter(struct i2c_adapter *adap) |
1da177e4 | 1632 | { |
35fc37f8 | 1633 | struct i2c_adapter *found; |
bbd2d9c9 | 1634 | struct i2c_client *client, *next; |
1da177e4 LT |
1635 | |
1636 | /* First make sure that this adapter was ever added */ | |
35fc37f8 JD |
1637 | mutex_lock(&core_lock); |
1638 | found = idr_find(&i2c_adapter_idr, adap->nr); | |
1639 | mutex_unlock(&core_lock); | |
1640 | if (found != adap) { | |
44239a5a | 1641 | pr_debug("attempting to delete unregistered adapter [%s]\n", adap->name); |
71546300 | 1642 | return; |
1da177e4 LT |
1643 | } |
1644 | ||
aec809fc | 1645 | i2c_acpi_remove_space_handler(adap); |
026526f5 | 1646 | /* Tell drivers about this removal */ |
35fc37f8 | 1647 | mutex_lock(&core_lock); |
19baba4c | 1648 | bus_for_each_drv(&i2c_bus_type, NULL, adap, |
69b0089a | 1649 | __process_removed_adapter); |
35fc37f8 | 1650 | mutex_unlock(&core_lock); |
1da177e4 | 1651 | |
bbd2d9c9 | 1652 | /* Remove devices instantiated from sysfs */ |
390946b1 JD |
1653 | mutex_lock_nested(&adap->userspace_clients_lock, |
1654 | i2c_adapter_depth(adap)); | |
6629dcff JD |
1655 | list_for_each_entry_safe(client, next, &adap->userspace_clients, |
1656 | detected) { | |
1657 | dev_dbg(&adap->dev, "Removing %s at 0x%x\n", client->name, | |
1658 | client->addr); | |
1659 | list_del(&client->detected); | |
1660 | i2c_unregister_device(client); | |
bbd2d9c9 | 1661 | } |
dafc50d1 | 1662 | mutex_unlock(&adap->userspace_clients_lock); |
bbd2d9c9 | 1663 | |
e549c2b5 | 1664 | /* Detach any active clients. This can't fail, thus we do not |
5219bf88 JD |
1665 | * check the returned value. This is a two-pass process, because |
1666 | * we can't remove the dummy devices during the first pass: they | |
1667 | * could have been instantiated by real devices wishing to clean | |
1668 | * them up properly, so we give them a chance to do that first. */ | |
19baba4c LPC |
1669 | device_for_each_child(&adap->dev, NULL, __unregister_client); |
1670 | device_for_each_child(&adap->dev, NULL, __unregister_dummy); | |
1da177e4 | 1671 | |
2bb5095a JD |
1672 | #ifdef CONFIG_I2C_COMPAT |
1673 | class_compat_remove_link(i2c_adapter_compat_class, &adap->dev, | |
1674 | adap->dev.parent); | |
1675 | #endif | |
1676 | ||
c5567521 TLSC |
1677 | /* device name is gone after device_unregister */ |
1678 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); | |
1679 | ||
9f924169 WS |
1680 | pm_runtime_disable(&adap->dev); |
1681 | ||
4d5538f5 BT |
1682 | i2c_host_notify_irq_teardown(adap); |
1683 | ||
26680ee2 WS |
1684 | /* wait until all references to the device are gone |
1685 | * | |
1686 | * FIXME: This is old code and should ideally be replaced by an | |
1687 | * alternative which results in decoupling the lifetime of the struct | |
1688 | * device from the i2c_adapter, like spi or netdev do. Any solution | |
95cc1e3d | 1689 | * should be thoroughly tested with DEBUG_KOBJECT_RELEASE enabled! |
26680ee2 | 1690 | */ |
1da177e4 | 1691 | init_completion(&adap->dev_released); |
1da177e4 | 1692 | device_unregister(&adap->dev); |
1da177e4 | 1693 | wait_for_completion(&adap->dev_released); |
1da177e4 | 1694 | |
6e13e641 | 1695 | /* free bus id */ |
35fc37f8 | 1696 | mutex_lock(&core_lock); |
1da177e4 | 1697 | idr_remove(&i2c_adapter_idr, adap->nr); |
35fc37f8 | 1698 | mutex_unlock(&core_lock); |
1da177e4 | 1699 | |
bd4bc3db JD |
1700 | /* Clear the device structure in case this adapter is ever going to be |
1701 | added again */ | |
1702 | memset(&adap->dev, 0, sizeof(adap->dev)); | |
1da177e4 | 1703 | } |
c0564606 | 1704 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 | 1705 | |
def00b32 WS |
1706 | static void i2c_parse_timing(struct device *dev, char *prop_name, u32 *cur_val_p, |
1707 | u32 def_val, bool use_def) | |
1708 | { | |
1709 | int ret; | |
1710 | ||
1711 | ret = device_property_read_u32(dev, prop_name, cur_val_p); | |
1712 | if (ret && use_def) | |
1713 | *cur_val_p = def_val; | |
1714 | ||
1715 | dev_dbg(dev, "%s: %u\n", prop_name, *cur_val_p); | |
1716 | } | |
1717 | ||
54177ccf WS |
1718 | /** |
1719 | * i2c_parse_fw_timings - get I2C related timing parameters from firmware | |
1720 | * @dev: The device to scan for I2C timing properties | |
1721 | * @t: the i2c_timings struct to be filled with values | |
1722 | * @use_defaults: bool to use sane defaults derived from the I2C specification | |
263a5646 | 1723 | * when properties are not found, otherwise don't update |
54177ccf WS |
1724 | * |
1725 | * Scan the device for the generic I2C properties describing timing parameters | |
1726 | * for the signal and fill the given struct with the results. If a property was | |
1727 | * not found and use_defaults was true, then maximum timings are assumed which | |
1728 | * are derived from the I2C specification. If use_defaults is not used, the | |
263a5646 AS |
1729 | * results will be as before, so drivers can apply their own defaults before |
1730 | * calling this helper. The latter is mainly intended for avoiding regressions | |
1731 | * of existing drivers which want to switch to this function. New drivers | |
1732 | * almost always should use the defaults. | |
54177ccf | 1733 | */ |
54177ccf WS |
1734 | void i2c_parse_fw_timings(struct device *dev, struct i2c_timings *t, bool use_defaults) |
1735 | { | |
def00b32 WS |
1736 | bool u = use_defaults; |
1737 | u32 d; | |
54177ccf | 1738 | |
def00b32 WS |
1739 | i2c_parse_timing(dev, "clock-frequency", &t->bus_freq_hz, |
1740 | I2C_MAX_STANDARD_MODE_FREQ, u); | |
4717be73 | 1741 | |
def00b32 WS |
1742 | d = t->bus_freq_hz <= I2C_MAX_STANDARD_MODE_FREQ ? 1000 : |
1743 | t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; | |
1744 | i2c_parse_timing(dev, "i2c-scl-rising-time-ns", &t->scl_rise_ns, d, u); | |
b84dfe1a | 1745 | |
def00b32 WS |
1746 | d = t->bus_freq_hz <= I2C_MAX_FAST_MODE_FREQ ? 300 : 120; |
1747 | i2c_parse_timing(dev, "i2c-scl-falling-time-ns", &t->scl_fall_ns, d, u); | |
b84dfe1a | 1748 | |
def00b32 WS |
1749 | i2c_parse_timing(dev, "i2c-scl-internal-delay-ns", |
1750 | &t->scl_int_delay_ns, 0, u); | |
1751 | i2c_parse_timing(dev, "i2c-sda-falling-time-ns", &t->sda_fall_ns, | |
1752 | t->scl_fall_ns, u); | |
1753 | i2c_parse_timing(dev, "i2c-sda-hold-time-ns", &t->sda_hold_ns, 0, u); | |
1754 | i2c_parse_timing(dev, "i2c-digital-filter-width-ns", | |
1755 | &t->digital_filter_width_ns, 0, u); | |
1756 | i2c_parse_timing(dev, "i2c-analog-filter-cutoff-frequency", | |
1757 | &t->analog_filter_cutoff_freq_hz, 0, u); | |
54177ccf WS |
1758 | } |
1759 | EXPORT_SYMBOL_GPL(i2c_parse_fw_timings); | |
1760 | ||
7b4fbc50 DB |
1761 | /* ------------------------------------------------------------------------- */ |
1762 | ||
edd7a563 | 1763 | int i2c_for_each_dev(void *data, int (*fn)(struct device *dev, void *data)) |
7ae31482 JD |
1764 | { |
1765 | int res; | |
1766 | ||
1767 | mutex_lock(&core_lock); | |
1768 | res = bus_for_each_dev(&i2c_bus_type, NULL, data, fn); | |
1769 | mutex_unlock(&core_lock); | |
1770 | ||
1771 | return res; | |
1772 | } | |
1773 | EXPORT_SYMBOL_GPL(i2c_for_each_dev); | |
1774 | ||
69b0089a | 1775 | static int __process_new_driver(struct device *dev, void *data) |
7f101a97 | 1776 | { |
4f8cf824 JD |
1777 | if (dev->type != &i2c_adapter_type) |
1778 | return 0; | |
69b0089a | 1779 | return i2c_do_add_adapter(data, to_i2c_adapter(dev)); |
7f101a97 DY |
1780 | } |
1781 | ||
7b4fbc50 DB |
1782 | /* |
1783 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
729d6dd5 | 1784 | * i2c slave chips, on a bus instance associated with some i2c_adapter. |
1da177e4 LT |
1785 | */ |
1786 | ||
de59cf9e | 1787 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 1788 | { |
7eebcb7c | 1789 | int res; |
1da177e4 | 1790 | |
1d0b19c9 | 1791 | /* Can't register until after driver model init */ |
95026658 | 1792 | if (WARN_ON(!is_registered)) |
1d0b19c9 DB |
1793 | return -EAGAIN; |
1794 | ||
1da177e4 | 1795 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 1796 | driver->driver.owner = owner; |
1da177e4 | 1797 | driver->driver.bus = &i2c_bus_type; |
147b36d5 | 1798 | INIT_LIST_HEAD(&driver->clients); |
1da177e4 | 1799 | |
729d6dd5 | 1800 | /* When registration returns, the driver core |
6e13e641 DB |
1801 | * will have called probe() for all matching-but-unbound devices. |
1802 | */ | |
1da177e4 LT |
1803 | res = driver_register(&driver->driver); |
1804 | if (res) | |
7eebcb7c | 1805 | return res; |
438d6c2c | 1806 | |
44239a5a | 1807 | pr_debug("driver [%s] registered\n", driver->driver.name); |
1da177e4 | 1808 | |
4735c98f | 1809 | /* Walk the adapters that are already present */ |
7ae31482 | 1810 | i2c_for_each_dev(driver, __process_new_driver); |
35fc37f8 | 1811 | |
7f101a97 DY |
1812 | return 0; |
1813 | } | |
1814 | EXPORT_SYMBOL(i2c_register_driver); | |
1815 | ||
69b0089a | 1816 | static int __process_removed_driver(struct device *dev, void *data) |
7f101a97 | 1817 | { |
19baba4c LPC |
1818 | if (dev->type == &i2c_adapter_type) |
1819 | i2c_do_del_adapter(data, to_i2c_adapter(dev)); | |
1820 | return 0; | |
1da177e4 LT |
1821 | } |
1822 | ||
a1d9e6e4 DB |
1823 | /** |
1824 | * i2c_del_driver - unregister I2C driver | |
1825 | * @driver: the driver being unregistered | |
d64f73be | 1826 | * Context: can sleep |
a1d9e6e4 | 1827 | */ |
b3e82096 | 1828 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 1829 | { |
7ae31482 | 1830 | i2c_for_each_dev(driver, __process_removed_driver); |
1da177e4 LT |
1831 | |
1832 | driver_unregister(&driver->driver); | |
44239a5a | 1833 | pr_debug("driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 1834 | } |
c0564606 | 1835 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 1836 | |
7b4fbc50 DB |
1837 | /* ------------------------------------------------------------------------- */ |
1838 | ||
9b766b81 DB |
1839 | struct i2c_cmd_arg { |
1840 | unsigned cmd; | |
1841 | void *arg; | |
1842 | }; | |
1843 | ||
1844 | static int i2c_cmd(struct device *dev, void *_arg) | |
1845 | { | |
1846 | struct i2c_client *client = i2c_verify_client(dev); | |
1847 | struct i2c_cmd_arg *arg = _arg; | |
0acc2b32 LPC |
1848 | struct i2c_driver *driver; |
1849 | ||
1850 | if (!client || !client->dev.driver) | |
1851 | return 0; | |
9b766b81 | 1852 | |
0acc2b32 LPC |
1853 | driver = to_i2c_driver(client->dev.driver); |
1854 | if (driver->command) | |
1855 | driver->command(client, arg->cmd, arg->arg); | |
9b766b81 DB |
1856 | return 0; |
1857 | } | |
1858 | ||
1da177e4 LT |
1859 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
1860 | { | |
9b766b81 | 1861 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 1862 | |
9b766b81 DB |
1863 | cmd_arg.cmd = cmd; |
1864 | cmd_arg.arg = arg; | |
1865 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 1866 | } |
c0564606 | 1867 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
1868 | |
1869 | static int __init i2c_init(void) | |
1870 | { | |
1871 | int retval; | |
1872 | ||
03bde7c3 WS |
1873 | retval = of_alias_get_highest_id("i2c"); |
1874 | ||
1875 | down_write(&__i2c_board_lock); | |
1876 | if (retval >= __i2c_first_dynamic_bus_num) | |
1877 | __i2c_first_dynamic_bus_num = retval + 1; | |
1878 | up_write(&__i2c_board_lock); | |
1879 | ||
1da177e4 | 1880 | retval = bus_register(&i2c_bus_type); |
1da177e4 LT |
1881 | if (retval) |
1882 | return retval; | |
b980a26d WS |
1883 | |
1884 | is_registered = true; | |
1885 | ||
2bb5095a JD |
1886 | #ifdef CONFIG_I2C_COMPAT |
1887 | i2c_adapter_compat_class = class_compat_register("i2c-adapter"); | |
1888 | if (!i2c_adapter_compat_class) { | |
1889 | retval = -ENOMEM; | |
1890 | goto bus_err; | |
1891 | } | |
1892 | #endif | |
e9f1373b DB |
1893 | retval = i2c_add_driver(&dummy_driver); |
1894 | if (retval) | |
2bb5095a | 1895 | goto class_err; |
ea7513bb PA |
1896 | |
1897 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) | |
1898 | WARN_ON(of_reconfig_notifier_register(&i2c_of_notifier)); | |
525e6fab OP |
1899 | if (IS_ENABLED(CONFIG_ACPI)) |
1900 | WARN_ON(acpi_reconfig_notifier_register(&i2c_acpi_notifier)); | |
ea7513bb | 1901 | |
e9f1373b DB |
1902 | return 0; |
1903 | ||
2bb5095a JD |
1904 | class_err: |
1905 | #ifdef CONFIG_I2C_COMPAT | |
1906 | class_compat_unregister(i2c_adapter_compat_class); | |
e9f1373b | 1907 | bus_err: |
2bb5095a | 1908 | #endif |
b980a26d | 1909 | is_registered = false; |
e9f1373b DB |
1910 | bus_unregister(&i2c_bus_type); |
1911 | return retval; | |
1da177e4 LT |
1912 | } |
1913 | ||
1914 | static void __exit i2c_exit(void) | |
1915 | { | |
525e6fab OP |
1916 | if (IS_ENABLED(CONFIG_ACPI)) |
1917 | WARN_ON(acpi_reconfig_notifier_unregister(&i2c_acpi_notifier)); | |
ea7513bb PA |
1918 | if (IS_ENABLED(CONFIG_OF_DYNAMIC)) |
1919 | WARN_ON(of_reconfig_notifier_unregister(&i2c_of_notifier)); | |
e9f1373b | 1920 | i2c_del_driver(&dummy_driver); |
2bb5095a JD |
1921 | #ifdef CONFIG_I2C_COMPAT |
1922 | class_compat_unregister(i2c_adapter_compat_class); | |
1923 | #endif | |
1da177e4 | 1924 | bus_unregister(&i2c_bus_type); |
d9a83d62 | 1925 | tracepoint_synchronize_unregister(); |
1da177e4 LT |
1926 | } |
1927 | ||
a10f9e7c DB |
1928 | /* We must initialize early, because some subsystems register i2c drivers |
1929 | * in subsys_initcall() code, but are linked (and initialized) before i2c. | |
1930 | */ | |
1931 | postcore_initcall(i2c_init); | |
1da177e4 LT |
1932 | module_exit(i2c_exit); |
1933 | ||
1934 | /* ---------------------------------------------------- | |
1935 | * the functional interface to the i2c busses. | |
1936 | * ---------------------------------------------------- | |
1937 | */ | |
1938 | ||
b7f62584 WS |
1939 | /* Check if val is exceeding the quirk IFF quirk is non 0 */ |
1940 | #define i2c_quirk_exceeded(val, quirk) ((quirk) && ((val) > (quirk))) | |
1941 | ||
1942 | static int i2c_quirk_error(struct i2c_adapter *adap, struct i2c_msg *msg, char *err_msg) | |
1943 | { | |
1944 | dev_err_ratelimited(&adap->dev, "adapter quirk: %s (addr 0x%04x, size %u, %s)\n", | |
1945 | err_msg, msg->addr, msg->len, | |
1946 | msg->flags & I2C_M_RD ? "read" : "write"); | |
1947 | return -EOPNOTSUPP; | |
1948 | } | |
1949 | ||
1950 | static int i2c_check_for_quirks(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
1951 | { | |
1952 | const struct i2c_adapter_quirks *q = adap->quirks; | |
1953 | int max_num = q->max_num_msgs, i; | |
1954 | bool do_len_check = true; | |
1955 | ||
1956 | if (q->flags & I2C_AQ_COMB) { | |
1957 | max_num = 2; | |
1958 | ||
1959 | /* special checks for combined messages */ | |
1960 | if (num == 2) { | |
1961 | if (q->flags & I2C_AQ_COMB_WRITE_FIRST && msgs[0].flags & I2C_M_RD) | |
1962 | return i2c_quirk_error(adap, &msgs[0], "1st comb msg must be write"); | |
1963 | ||
1964 | if (q->flags & I2C_AQ_COMB_READ_SECOND && !(msgs[1].flags & I2C_M_RD)) | |
1965 | return i2c_quirk_error(adap, &msgs[1], "2nd comb msg must be read"); | |
1966 | ||
1967 | if (q->flags & I2C_AQ_COMB_SAME_ADDR && msgs[0].addr != msgs[1].addr) | |
1968 | return i2c_quirk_error(adap, &msgs[0], "comb msg only to same addr"); | |
1969 | ||
1970 | if (i2c_quirk_exceeded(msgs[0].len, q->max_comb_1st_msg_len)) | |
1971 | return i2c_quirk_error(adap, &msgs[0], "msg too long"); | |
1972 | ||
1973 | if (i2c_quirk_exceeded(msgs[1].len, q->max_comb_2nd_msg_len)) | |
1974 | return i2c_quirk_error(adap, &msgs[1], "msg too long"); | |
1975 | ||
1976 | do_len_check = false; | |
1977 | } | |
1978 | } | |
1979 | ||
1980 | if (i2c_quirk_exceeded(num, max_num)) | |
1981 | return i2c_quirk_error(adap, &msgs[0], "too many messages"); | |
1982 | ||
1983 | for (i = 0; i < num; i++) { | |
1984 | u16 len = msgs[i].len; | |
1985 | ||
1986 | if (msgs[i].flags & I2C_M_RD) { | |
1987 | if (do_len_check && i2c_quirk_exceeded(len, q->max_read_len)) | |
1988 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
d9cfe2ce WS |
1989 | |
1990 | if (q->flags & I2C_AQ_NO_ZERO_LEN_READ && len == 0) | |
1991 | return i2c_quirk_error(adap, &msgs[i], "no zero length"); | |
b7f62584 WS |
1992 | } else { |
1993 | if (do_len_check && i2c_quirk_exceeded(len, q->max_write_len)) | |
1994 | return i2c_quirk_error(adap, &msgs[i], "msg too long"); | |
d9cfe2ce WS |
1995 | |
1996 | if (q->flags & I2C_AQ_NO_ZERO_LEN_WRITE && len == 0) | |
1997 | return i2c_quirk_error(adap, &msgs[i], "no zero length"); | |
b7f62584 WS |
1998 | } |
1999 | } | |
2000 | ||
2001 | return 0; | |
2002 | } | |
2003 | ||
b37d2a3a JD |
2004 | /** |
2005 | * __i2c_transfer - unlocked flavor of i2c_transfer | |
2006 | * @adap: Handle to I2C bus | |
2007 | * @msgs: One or more messages to execute before STOP is issued to | |
2008 | * terminate the operation; each message begins with a START. | |
2009 | * @num: Number of messages to be executed. | |
2010 | * | |
2011 | * Returns negative errno, else the number of messages executed. | |
2012 | * | |
2013 | * Adapter lock must be held when calling this function. No debug logging | |
2014 | * takes place. adap->algo->master_xfer existence isn't checked. | |
2015 | */ | |
2016 | int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) | |
2017 | { | |
2018 | unsigned long orig_jiffies; | |
2019 | int ret, try; | |
2020 | ||
1eace834 AB |
2021 | if (WARN_ON(!msgs || num < 1)) |
2022 | return -EINVAL; | |
5d756112 WS |
2023 | |
2024 | ret = __i2c_check_suspended(adap); | |
2025 | if (ret) | |
2026 | return ret; | |
1eace834 | 2027 | |
b7f62584 WS |
2028 | if (adap->quirks && i2c_check_for_quirks(adap, msgs, num)) |
2029 | return -EOPNOTSUPP; | |
2030 | ||
50888b01 DB |
2031 | /* |
2032 | * i2c_trace_msg_key gets enabled when tracepoint i2c_transfer gets | |
d9a83d62 DH |
2033 | * enabled. This is an efficient way of keeping the for-loop from |
2034 | * being executed when not needed. | |
2035 | */ | |
50888b01 | 2036 | if (static_branch_unlikely(&i2c_trace_msg_key)) { |
d9a83d62 DH |
2037 | int i; |
2038 | for (i = 0; i < num; i++) | |
2039 | if (msgs[i].flags & I2C_M_RD) | |
2040 | trace_i2c_read(adap, &msgs[i], i); | |
2041 | else | |
2042 | trace_i2c_write(adap, &msgs[i], i); | |
2043 | } | |
2044 | ||
b37d2a3a JD |
2045 | /* Retry automatically on arbitration loss */ |
2046 | orig_jiffies = jiffies; | |
2047 | for (ret = 0, try = 0; try <= adap->retries; try++) { | |
63b96983 WS |
2048 | if (i2c_in_atomic_xfer_mode() && adap->algo->master_xfer_atomic) |
2049 | ret = adap->algo->master_xfer_atomic(adap, msgs, num); | |
2050 | else | |
2051 | ret = adap->algo->master_xfer(adap, msgs, num); | |
2052 | ||
b37d2a3a JD |
2053 | if (ret != -EAGAIN) |
2054 | break; | |
2055 | if (time_after(jiffies, orig_jiffies + adap->timeout)) | |
2056 | break; | |
2057 | } | |
2058 | ||
50888b01 | 2059 | if (static_branch_unlikely(&i2c_trace_msg_key)) { |
d9a83d62 DH |
2060 | int i; |
2061 | for (i = 0; i < ret; i++) | |
2062 | if (msgs[i].flags & I2C_M_RD) | |
2063 | trace_i2c_reply(adap, &msgs[i], i); | |
4a3f7691 | 2064 | trace_i2c_result(adap, num, ret); |
d9a83d62 DH |
2065 | } |
2066 | ||
b37d2a3a JD |
2067 | return ret; |
2068 | } | |
2069 | EXPORT_SYMBOL(__i2c_transfer); | |
2070 | ||
a1cdedac DB |
2071 | /** |
2072 | * i2c_transfer - execute a single or combined I2C message | |
2073 | * @adap: Handle to I2C bus | |
2074 | * @msgs: One or more messages to execute before STOP is issued to | |
2075 | * terminate the operation; each message begins with a START. | |
2076 | * @num: Number of messages to be executed. | |
2077 | * | |
2078 | * Returns negative errno, else the number of messages executed. | |
2079 | * | |
2080 | * Note that there is no requirement that each message be sent to | |
2081 | * the same slave address, although that is the most common model. | |
2082 | */ | |
09b8ce0a | 2083 | int i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) |
1da177e4 | 2084 | { |
b37d2a3a | 2085 | int ret; |
1da177e4 | 2086 | |
cc52612e WS |
2087 | if (!adap->algo->master_xfer) { |
2088 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
2089 | return -EOPNOTSUPP; | |
2090 | } | |
2091 | ||
a1cdedac DB |
2092 | /* REVISIT the fault reporting model here is weak: |
2093 | * | |
2094 | * - When we get an error after receiving N bytes from a slave, | |
2095 | * there is no way to report "N". | |
2096 | * | |
2097 | * - When we get a NAK after transmitting N bytes to a slave, | |
2098 | * there is no way to report "N" ... or to let the master | |
2099 | * continue executing the rest of this combined message, if | |
2100 | * that's the appropriate response. | |
2101 | * | |
2102 | * - When for example "num" is two and we successfully complete | |
2103 | * the first message but get an error part way through the | |
2104 | * second, it's unclear whether that should be reported as | |
2105 | * one (discarding status on the second message) or errno | |
2106 | * (discarding status on the first one). | |
2107 | */ | |
83c42212 WS |
2108 | ret = __i2c_lock_bus_helper(adap); |
2109 | if (ret) | |
2110 | return ret; | |
cc52612e WS |
2111 | |
2112 | ret = __i2c_transfer(adap, msgs, num); | |
2113 | i2c_unlock_bus(adap, I2C_LOCK_SEGMENT); | |
2114 | ||
2115 | return ret; | |
1da177e4 | 2116 | } |
c0564606 | 2117 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 | 2118 | |
a1cdedac | 2119 | /** |
8a91732b WS |
2120 | * i2c_transfer_buffer_flags - issue a single I2C message transferring data |
2121 | * to/from a buffer | |
a1cdedac | 2122 | * @client: Handle to slave device |
8a91732b WS |
2123 | * @buf: Where the data is stored |
2124 | * @count: How many bytes to transfer, must be less than 64k since msg.len is u16 | |
2125 | * @flags: The flags to be used for the message, e.g. I2C_M_RD for reads | |
a1cdedac | 2126 | * |
8a91732b | 2127 | * Returns negative errno, or else the number of bytes transferred. |
a1cdedac | 2128 | */ |
8a91732b WS |
2129 | int i2c_transfer_buffer_flags(const struct i2c_client *client, char *buf, |
2130 | int count, u16 flags) | |
1da177e4 | 2131 | { |
1da177e4 | 2132 | int ret; |
8a91732b WS |
2133 | struct i2c_msg msg = { |
2134 | .addr = client->addr, | |
2135 | .flags = flags | (client->flags & I2C_M_TEN), | |
2136 | .len = count, | |
2137 | .buf = buf, | |
2138 | }; | |
815f55f2 | 2139 | |
8a91732b | 2140 | ret = i2c_transfer(client->adapter, &msg, 1); |
815f55f2 | 2141 | |
834aa6f3 | 2142 | /* |
8a91732b WS |
2143 | * If everything went ok (i.e. 1 msg transferred), return #bytes |
2144 | * transferred, else error code. | |
834aa6f3 | 2145 | */ |
815f55f2 | 2146 | return (ret == 1) ? count : ret; |
1da177e4 | 2147 | } |
8a91732b | 2148 | EXPORT_SYMBOL(i2c_transfer_buffer_flags); |
1da177e4 | 2149 | |
dde67eb1 PR |
2150 | /** |
2151 | * i2c_get_device_id - get manufacturer, part id and die revision of a device | |
2152 | * @client: The device to query | |
2153 | * @id: The queried information | |
2154 | * | |
2155 | * Returns negative errno on error, zero on success. | |
2156 | */ | |
2157 | int i2c_get_device_id(const struct i2c_client *client, | |
2158 | struct i2c_device_identity *id) | |
2159 | { | |
2160 | struct i2c_adapter *adap = client->adapter; | |
2161 | union i2c_smbus_data raw_id; | |
2162 | int ret; | |
2163 | ||
2164 | if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_I2C_BLOCK)) | |
2165 | return -EOPNOTSUPP; | |
2166 | ||
2167 | raw_id.block[0] = 3; | |
2168 | ret = i2c_smbus_xfer(adap, I2C_ADDR_DEVICE_ID, 0, | |
2169 | I2C_SMBUS_READ, client->addr << 1, | |
2170 | I2C_SMBUS_I2C_BLOCK_DATA, &raw_id); | |
2171 | if (ret) | |
2172 | return ret; | |
2173 | ||
2174 | id->manufacturer_id = (raw_id.block[1] << 4) | (raw_id.block[2] >> 4); | |
2175 | id->part_id = ((raw_id.block[2] & 0xf) << 5) | (raw_id.block[3] >> 3); | |
2176 | id->die_revision = raw_id.block[3] & 0x7; | |
2177 | return 0; | |
2178 | } | |
2179 | EXPORT_SYMBOL_GPL(i2c_get_device_id); | |
2180 | ||
1da177e4 LT |
2181 | /* ---------------------------------------------------- |
2182 | * the i2c address scanning function | |
2183 | * Will not work for 10-bit addresses! | |
2184 | * ---------------------------------------------------- | |
2185 | */ | |
1da177e4 | 2186 | |
63e4e802 JD |
2187 | /* |
2188 | * Legacy default probe function, mostly relevant for SMBus. The default | |
2189 | * probe method is a quick write, but it is known to corrupt the 24RF08 | |
2190 | * EEPROMs due to a state machine bug, and could also irreversibly | |
2191 | * write-protect some EEPROMs, so for address ranges 0x30-0x37 and 0x50-0x5f, | |
2192 | * we use a short byte read instead. Also, some bus drivers don't implement | |
2193 | * quick write, so we fallback to a byte read in that case too. | |
2194 | * On x86, there is another special case for FSC hardware monitoring chips, | |
2195 | * which want regular byte reads (address 0x73.) Fortunately, these are the | |
2196 | * only known chips using this I2C address on PC hardware. | |
2197 | * Returns 1 if probe succeeded, 0 if not. | |
2198 | */ | |
2199 | static int i2c_default_probe(struct i2c_adapter *adap, unsigned short addr) | |
2200 | { | |
2201 | int err; | |
2202 | union i2c_smbus_data dummy; | |
2203 | ||
2204 | #ifdef CONFIG_X86 | |
2205 | if (addr == 0x73 && (adap->class & I2C_CLASS_HWMON) | |
2206 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE_DATA)) | |
2207 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2208 | I2C_SMBUS_BYTE_DATA, &dummy); | |
2209 | else | |
2210 | #endif | |
8031d79b JD |
2211 | if (!((addr & ~0x07) == 0x30 || (addr & ~0x0f) == 0x50) |
2212 | && i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) | |
63e4e802 JD |
2213 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_WRITE, 0, |
2214 | I2C_SMBUS_QUICK, NULL); | |
8031d79b JD |
2215 | else if (i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) |
2216 | err = i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2217 | I2C_SMBUS_BYTE, &dummy); | |
2218 | else { | |
d63a9e85 AL |
2219 | dev_warn(&adap->dev, "No suitable probing method supported for address 0x%02X\n", |
2220 | addr); | |
8031d79b JD |
2221 | err = -EOPNOTSUPP; |
2222 | } | |
63e4e802 JD |
2223 | |
2224 | return err >= 0; | |
2225 | } | |
2226 | ||
ccfbbd08 | 2227 | static int i2c_detect_address(struct i2c_client *temp_client, |
4735c98f JD |
2228 | struct i2c_driver *driver) |
2229 | { | |
2230 | struct i2c_board_info info; | |
2231 | struct i2c_adapter *adapter = temp_client->adapter; | |
2232 | int addr = temp_client->addr; | |
2233 | int err; | |
2234 | ||
2235 | /* Make sure the address is valid */ | |
66be6056 | 2236 | err = i2c_check_7bit_addr_validity_strict(addr); |
656b8761 | 2237 | if (err) { |
4735c98f JD |
2238 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", |
2239 | addr); | |
656b8761 | 2240 | return err; |
4735c98f JD |
2241 | } |
2242 | ||
9bccc70a | 2243 | /* Skip if already in use (7 bit, no need to encode flags) */ |
3b5f794b | 2244 | if (i2c_check_addr_busy(adapter, addr)) |
4735c98f JD |
2245 | return 0; |
2246 | ||
ccfbbd08 | 2247 | /* Make sure there is something at this address */ |
63e4e802 JD |
2248 | if (!i2c_default_probe(adapter, addr)) |
2249 | return 0; | |
4735c98f JD |
2250 | |
2251 | /* Finally call the custom detection function */ | |
2252 | memset(&info, 0, sizeof(struct i2c_board_info)); | |
2253 | info.addr = addr; | |
310ec792 | 2254 | err = driver->detect(temp_client, &info); |
4735c98f JD |
2255 | if (err) { |
2256 | /* -ENODEV is returned if the detection fails. We catch it | |
2257 | here as this isn't an error. */ | |
2258 | return err == -ENODEV ? 0 : err; | |
2259 | } | |
2260 | ||
2261 | /* Consistency check */ | |
2262 | if (info.type[0] == '\0') { | |
b93d3d37 AS |
2263 | dev_err(&adapter->dev, |
2264 | "%s detection function provided no name for 0x%x\n", | |
2265 | driver->driver.name, addr); | |
4735c98f JD |
2266 | } else { |
2267 | struct i2c_client *client; | |
2268 | ||
2269 | /* Detection succeeded, instantiate the device */ | |
0c176170 WS |
2270 | if (adapter->class & I2C_CLASS_DEPRECATED) |
2271 | dev_warn(&adapter->dev, | |
2272 | "This adapter will soon drop class based instantiation of devices. " | |
2273 | "Please make sure client 0x%02x gets instantiated by other means. " | |
ccf988b6 | 2274 | "Check 'Documentation/i2c/instantiating-devices.rst' for details.\n", |
0c176170 WS |
2275 | info.addr); |
2276 | ||
4735c98f JD |
2277 | dev_dbg(&adapter->dev, "Creating %s at 0x%02x\n", |
2278 | info.type, info.addr); | |
87e07437 WS |
2279 | client = i2c_new_client_device(adapter, &info); |
2280 | if (!IS_ERR(client)) | |
4735c98f JD |
2281 | list_add_tail(&client->detected, &driver->clients); |
2282 | else | |
2283 | dev_err(&adapter->dev, "Failed creating %s at 0x%02x\n", | |
2284 | info.type, info.addr); | |
2285 | } | |
2286 | return 0; | |
2287 | } | |
2288 | ||
2289 | static int i2c_detect(struct i2c_adapter *adapter, struct i2c_driver *driver) | |
2290 | { | |
c3813d6a | 2291 | const unsigned short *address_list; |
4735c98f JD |
2292 | struct i2c_client *temp_client; |
2293 | int i, err = 0; | |
4735c98f | 2294 | |
c3813d6a JD |
2295 | address_list = driver->address_list; |
2296 | if (!driver->detect || !address_list) | |
4735c98f JD |
2297 | return 0; |
2298 | ||
45552272 WS |
2299 | /* Warn that the adapter lost class based instantiation */ |
2300 | if (adapter->class == I2C_CLASS_DEPRECATED) { | |
2301 | dev_dbg(&adapter->dev, | |
b93d3d37 | 2302 | "This adapter dropped support for I2C classes and won't auto-detect %s devices anymore. " |
ccf988b6 | 2303 | "If you need it, check 'Documentation/i2c/instantiating-devices.rst' for alternatives.\n", |
45552272 WS |
2304 | driver->driver.name); |
2305 | return 0; | |
2306 | } | |
2307 | ||
51b54ba9 JD |
2308 | /* Stop here if the classes do not match */ |
2309 | if (!(adapter->class & driver->class)) | |
2310 | return 0; | |
2311 | ||
4735c98f JD |
2312 | /* Set up a temporary client to help detect callback */ |
2313 | temp_client = kzalloc(sizeof(struct i2c_client), GFP_KERNEL); | |
2314 | if (!temp_client) | |
2315 | return -ENOMEM; | |
2316 | temp_client->adapter = adapter; | |
2317 | ||
c3813d6a | 2318 | for (i = 0; address_list[i] != I2C_CLIENT_END; i += 1) { |
b93d3d37 AS |
2319 | dev_dbg(&adapter->dev, |
2320 | "found normal entry for adapter %d, addr 0x%02x\n", | |
dd4f2ca9 | 2321 | i2c_adapter_id(adapter), address_list[i]); |
c3813d6a | 2322 | temp_client->addr = address_list[i]; |
ccfbbd08 | 2323 | err = i2c_detect_address(temp_client, driver); |
51b54ba9 JD |
2324 | if (unlikely(err)) |
2325 | break; | |
4735c98f JD |
2326 | } |
2327 | ||
4735c98f JD |
2328 | kfree(temp_client); |
2329 | return err; | |
2330 | } | |
2331 | ||
d44f19d5 JD |
2332 | int i2c_probe_func_quick_read(struct i2c_adapter *adap, unsigned short addr) |
2333 | { | |
2334 | return i2c_smbus_xfer(adap, addr, 0, I2C_SMBUS_READ, 0, | |
2335 | I2C_SMBUS_QUICK, NULL) >= 0; | |
2336 | } | |
2337 | EXPORT_SYMBOL_GPL(i2c_probe_func_quick_read); | |
2338 | ||
12b5053a | 2339 | struct i2c_client * |
c1d08475 WS |
2340 | i2c_new_scanned_device(struct i2c_adapter *adap, |
2341 | struct i2c_board_info *info, | |
2342 | unsigned short const *addr_list, | |
2343 | int (*probe)(struct i2c_adapter *adap, unsigned short addr)) | |
12b5053a JD |
2344 | { |
2345 | int i; | |
2346 | ||
8031d79b | 2347 | if (!probe) |
9a94241a | 2348 | probe = i2c_default_probe; |
12b5053a | 2349 | |
12b5053a JD |
2350 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
2351 | /* Check address validity */ | |
66be6056 | 2352 | if (i2c_check_7bit_addr_validity_strict(addr_list[i]) < 0) { |
b93d3d37 AS |
2353 | dev_warn(&adap->dev, "Invalid 7-bit address 0x%02x\n", |
2354 | addr_list[i]); | |
12b5053a JD |
2355 | continue; |
2356 | } | |
2357 | ||
9bccc70a | 2358 | /* Check address availability (7 bit, no need to encode flags) */ |
3b5f794b | 2359 | if (i2c_check_addr_busy(adap, addr_list[i])) { |
b93d3d37 AS |
2360 | dev_dbg(&adap->dev, |
2361 | "Address 0x%02x already in use, not probing\n", | |
2362 | addr_list[i]); | |
12b5053a JD |
2363 | continue; |
2364 | } | |
2365 | ||
63e4e802 | 2366 | /* Test address responsiveness */ |
9a94241a | 2367 | if (probe(adap, addr_list[i])) |
63e4e802 | 2368 | break; |
12b5053a | 2369 | } |
12b5053a JD |
2370 | |
2371 | if (addr_list[i] == I2C_CLIENT_END) { | |
2372 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
c1d08475 | 2373 | return ERR_PTR(-ENODEV); |
12b5053a JD |
2374 | } |
2375 | ||
2376 | info->addr = addr_list[i]; | |
c1d08475 WS |
2377 | return i2c_new_client_device(adap, info); |
2378 | } | |
2379 | EXPORT_SYMBOL_GPL(i2c_new_scanned_device); | |
2380 | ||
d735b34d | 2381 | struct i2c_adapter *i2c_get_adapter(int nr) |
1da177e4 | 2382 | { |
1da177e4 | 2383 | struct i2c_adapter *adapter; |
438d6c2c | 2384 | |
caada32a | 2385 | mutex_lock(&core_lock); |
d735b34d | 2386 | adapter = idr_find(&i2c_adapter_idr, nr); |
611e12ea VZ |
2387 | if (!adapter) |
2388 | goto exit; | |
2389 | ||
2390 | if (try_module_get(adapter->owner)) | |
2391 | get_device(&adapter->dev); | |
2392 | else | |
a0920e10 MH |
2393 | adapter = NULL; |
2394 | ||
611e12ea | 2395 | exit: |
caada32a | 2396 | mutex_unlock(&core_lock); |
a0920e10 | 2397 | return adapter; |
1da177e4 | 2398 | } |
c0564606 | 2399 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
2400 | |
2401 | void i2c_put_adapter(struct i2c_adapter *adap) | |
2402 | { | |
611e12ea VZ |
2403 | if (!adap) |
2404 | return; | |
2405 | ||
2406 | put_device(&adap->dev); | |
2407 | module_put(adap->owner); | |
1da177e4 | 2408 | } |
c0564606 | 2409 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 | 2410 | |
e94bc5d1 WS |
2411 | /** |
2412 | * i2c_get_dma_safe_msg_buf() - get a DMA safe buffer for the given i2c_msg | |
2413 | * @msg: the message to be checked | |
bf263c35 WS |
2414 | * @threshold: the minimum number of bytes for which using DMA makes sense. |
2415 | * Should at least be 1. | |
e94bc5d1 WS |
2416 | * |
2417 | * Return: NULL if a DMA safe buffer was not obtained. Use msg->buf with PIO. | |
2418 | * Or a valid pointer to be used with DMA. After use, release it by | |
34d1b82c | 2419 | * calling i2c_put_dma_safe_msg_buf(). |
e94bc5d1 WS |
2420 | * |
2421 | * This function must only be called from process context! | |
2422 | */ | |
2423 | u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold) | |
2424 | { | |
bf263c35 WS |
2425 | /* also skip 0-length msgs for bogus thresholds of 0 */ |
2426 | if (!threshold) | |
2427 | pr_debug("DMA buffer for addr=0x%02x with length 0 is bogus\n", | |
2428 | msg->addr); | |
2429 | if (msg->len < threshold || msg->len == 0) | |
e94bc5d1 WS |
2430 | return NULL; |
2431 | ||
2432 | if (msg->flags & I2C_M_DMA_SAFE) | |
2433 | return msg->buf; | |
2434 | ||
2435 | pr_debug("using bounce buffer for addr=0x%02x, len=%d\n", | |
2436 | msg->addr, msg->len); | |
2437 | ||
2438 | if (msg->flags & I2C_M_RD) | |
2439 | return kzalloc(msg->len, GFP_KERNEL); | |
2440 | else | |
2441 | return kmemdup(msg->buf, msg->len, GFP_KERNEL); | |
2442 | } | |
2443 | EXPORT_SYMBOL_GPL(i2c_get_dma_safe_msg_buf); | |
2444 | ||
2445 | /** | |
82fe39a6 | 2446 | * i2c_put_dma_safe_msg_buf - release DMA safe buffer and sync with i2c_msg |
e94bc5d1 | 2447 | * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL. |
82fe39a6 WS |
2448 | * @msg: the message which the buffer corresponds to |
2449 | * @xferred: bool saying if the message was transferred | |
e94bc5d1 | 2450 | */ |
82fe39a6 | 2451 | void i2c_put_dma_safe_msg_buf(u8 *buf, struct i2c_msg *msg, bool xferred) |
e94bc5d1 WS |
2452 | { |
2453 | if (!buf || buf == msg->buf) | |
2454 | return; | |
2455 | ||
82fe39a6 | 2456 | if (xferred && msg->flags & I2C_M_RD) |
e94bc5d1 WS |
2457 | memcpy(msg->buf, buf, msg->len); |
2458 | ||
2459 | kfree(buf); | |
2460 | } | |
82fe39a6 | 2461 | EXPORT_SYMBOL_GPL(i2c_put_dma_safe_msg_buf); |
e94bc5d1 | 2462 | |
1da177e4 LT |
2463 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); |
2464 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
2465 | MODULE_LICENSE("GPL"); |