Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* i2c-core.c - a device driver for the iic-bus interface */ |
2 | /* ------------------------------------------------------------------------- */ | |
3 | /* Copyright (C) 1995-99 Simon G. Vogl | |
4 | ||
5 | This program is free software; you can redistribute it and/or modify | |
6 | it under the terms of the GNU General Public License as published by | |
7 | the Free Software Foundation; either version 2 of the License, or | |
8 | (at your option) any later version. | |
9 | ||
10 | This program is distributed in the hope that it will be useful, | |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
13 | GNU General Public License for more details. | |
14 | ||
15 | You should have received a copy of the GNU General Public License | |
16 | along with this program; if not, write to the Free Software | |
17 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
18 | /* ------------------------------------------------------------------------- */ | |
19 | ||
96de0e25 | 20 | /* With some changes from Kyösti Mälkki <kmalkki@cc.hut.fi>. |
1da177e4 | 21 | All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl> |
421ef47b JD |
22 | SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and |
23 | Jean Delvare <khali@linux-fr.org> */ | |
1da177e4 | 24 | |
1da177e4 LT |
25 | #include <linux/module.h> |
26 | #include <linux/kernel.h> | |
27 | #include <linux/errno.h> | |
28 | #include <linux/slab.h> | |
29 | #include <linux/i2c.h> | |
30 | #include <linux/init.h> | |
31 | #include <linux/idr.h> | |
32 | #include <linux/seq_file.h> | |
d052d1be | 33 | #include <linux/platform_device.h> |
b3585e4f | 34 | #include <linux/mutex.h> |
b8d6f45b | 35 | #include <linux/completion.h> |
cea443a8 MR |
36 | #include <linux/hardirq.h> |
37 | #include <linux/irqflags.h> | |
6188e10d | 38 | #include <linux/semaphore.h> |
1da177e4 LT |
39 | #include <asm/uaccess.h> |
40 | ||
9c1600ed DB |
41 | #include "i2c-core.h" |
42 | ||
1da177e4 | 43 | |
caada32a | 44 | static DEFINE_MUTEX(core_lock); |
1da177e4 LT |
45 | static DEFINE_IDR(i2c_adapter_idr); |
46 | ||
a1d9e6e4 | 47 | #define is_newstyle_driver(d) ((d)->probe || (d)->remove) |
f37dd80a DB |
48 | |
49 | /* ------------------------------------------------------------------------- */ | |
50 | ||
d2653e92 JD |
51 | static const struct i2c_device_id *i2c_match_id(const struct i2c_device_id *id, |
52 | const struct i2c_client *client) | |
53 | { | |
54 | while (id->name[0]) { | |
55 | if (strcmp(client->name, id->name) == 0) | |
56 | return id; | |
57 | id++; | |
58 | } | |
59 | return NULL; | |
60 | } | |
61 | ||
1da177e4 LT |
62 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
63 | { | |
7b4fbc50 DB |
64 | struct i2c_client *client = to_i2c_client(dev); |
65 | struct i2c_driver *driver = to_i2c_driver(drv); | |
66 | ||
67 | /* make legacy i2c drivers bypass driver model probing entirely; | |
68 | * such drivers scan each i2c adapter/bus themselves. | |
69 | */ | |
a1d9e6e4 | 70 | if (!is_newstyle_driver(driver)) |
7b4fbc50 DB |
71 | return 0; |
72 | ||
d2653e92 JD |
73 | /* match on an id table if there is one */ |
74 | if (driver->id_table) | |
75 | return i2c_match_id(driver->id_table, client) != NULL; | |
76 | ||
7b4fbc50 DB |
77 | /* new style drivers use the same kind of driver matching policy |
78 | * as platform devices or SPI: compare device and driver IDs. | |
79 | */ | |
80 | return strcmp(client->driver_name, drv->name) == 0; | |
1da177e4 LT |
81 | } |
82 | ||
7b4fbc50 DB |
83 | #ifdef CONFIG_HOTPLUG |
84 | ||
85 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 86 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
87 | { |
88 | struct i2c_client *client = to_i2c_client(dev); | |
7b4fbc50 DB |
89 | |
90 | /* by definition, legacy drivers can't hotplug */ | |
d2653e92 | 91 | if (dev->driver) |
7b4fbc50 DB |
92 | return 0; |
93 | ||
d2653e92 JD |
94 | if (client->driver_name[0]) { |
95 | if (add_uevent_var(env, "MODALIAS=%s", client->driver_name)) | |
96 | return -ENOMEM; | |
97 | } else { | |
98 | if (add_uevent_var(env, "MODALIAS=%s%s", | |
99 | I2C_MODULE_PREFIX, client->name)) | |
100 | return -ENOMEM; | |
101 | } | |
7b4fbc50 DB |
102 | dev_dbg(dev, "uevent\n"); |
103 | return 0; | |
104 | } | |
105 | ||
106 | #else | |
107 | #define i2c_device_uevent NULL | |
108 | #endif /* CONFIG_HOTPLUG */ | |
109 | ||
f37dd80a | 110 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 111 | { |
7b4fbc50 DB |
112 | struct i2c_client *client = to_i2c_client(dev); |
113 | struct i2c_driver *driver = to_i2c_driver(dev->driver); | |
d2653e92 | 114 | const struct i2c_device_id *id; |
50c3304a | 115 | int status; |
7b4fbc50 DB |
116 | |
117 | if (!driver->probe) | |
118 | return -ENODEV; | |
119 | client->driver = driver; | |
120 | dev_dbg(dev, "probe\n"); | |
d2653e92 JD |
121 | |
122 | if (driver->id_table) | |
123 | id = i2c_match_id(driver->id_table, client); | |
124 | else | |
125 | id = NULL; | |
126 | status = driver->probe(client, id); | |
50c3304a HV |
127 | if (status) |
128 | client->driver = NULL; | |
129 | return status; | |
f37dd80a | 130 | } |
1da177e4 | 131 | |
f37dd80a DB |
132 | static int i2c_device_remove(struct device *dev) |
133 | { | |
a1d9e6e4 DB |
134 | struct i2c_client *client = to_i2c_client(dev); |
135 | struct i2c_driver *driver; | |
136 | int status; | |
137 | ||
138 | if (!dev->driver) | |
139 | return 0; | |
140 | ||
141 | driver = to_i2c_driver(dev->driver); | |
142 | if (driver->remove) { | |
143 | dev_dbg(dev, "remove\n"); | |
144 | status = driver->remove(client); | |
145 | } else { | |
146 | dev->driver = NULL; | |
147 | status = 0; | |
148 | } | |
149 | if (status == 0) | |
150 | client->driver = NULL; | |
151 | return status; | |
1da177e4 LT |
152 | } |
153 | ||
f37dd80a | 154 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 155 | { |
f37dd80a DB |
156 | struct i2c_driver *driver; |
157 | ||
158 | if (!dev->driver) | |
159 | return; | |
160 | driver = to_i2c_driver(dev->driver); | |
161 | if (driver->shutdown) | |
162 | driver->shutdown(to_i2c_client(dev)); | |
1da177e4 LT |
163 | } |
164 | ||
f37dd80a | 165 | static int i2c_device_suspend(struct device * dev, pm_message_t mesg) |
1da177e4 | 166 | { |
f37dd80a DB |
167 | struct i2c_driver *driver; |
168 | ||
169 | if (!dev->driver) | |
170 | return 0; | |
171 | driver = to_i2c_driver(dev->driver); | |
172 | if (!driver->suspend) | |
173 | return 0; | |
174 | return driver->suspend(to_i2c_client(dev), mesg); | |
1da177e4 LT |
175 | } |
176 | ||
f37dd80a | 177 | static int i2c_device_resume(struct device * dev) |
1da177e4 | 178 | { |
f37dd80a DB |
179 | struct i2c_driver *driver; |
180 | ||
181 | if (!dev->driver) | |
182 | return 0; | |
183 | driver = to_i2c_driver(dev->driver); | |
184 | if (!driver->resume) | |
185 | return 0; | |
186 | return driver->resume(to_i2c_client(dev)); | |
1da177e4 LT |
187 | } |
188 | ||
7b4fbc50 DB |
189 | static void i2c_client_release(struct device *dev) |
190 | { | |
191 | struct i2c_client *client = to_i2c_client(dev); | |
192 | complete(&client->released); | |
193 | } | |
194 | ||
9c1600ed DB |
195 | static void i2c_client_dev_release(struct device *dev) |
196 | { | |
197 | kfree(to_i2c_client(dev)); | |
198 | } | |
199 | ||
7b4fbc50 DB |
200 | static ssize_t show_client_name(struct device *dev, struct device_attribute *attr, char *buf) |
201 | { | |
202 | struct i2c_client *client = to_i2c_client(dev); | |
203 | return sprintf(buf, "%s\n", client->name); | |
204 | } | |
205 | ||
206 | static ssize_t show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
207 | { | |
208 | struct i2c_client *client = to_i2c_client(dev); | |
d2653e92 | 209 | return client->driver_name[0] |
7b4fbc50 | 210 | ? sprintf(buf, "%s\n", client->driver_name) |
d2653e92 | 211 | : sprintf(buf, "%s%s\n", I2C_MODULE_PREFIX, client->name); |
7b4fbc50 DB |
212 | } |
213 | ||
214 | static struct device_attribute i2c_dev_attrs[] = { | |
215 | __ATTR(name, S_IRUGO, show_client_name, NULL), | |
216 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ | |
217 | __ATTR(modalias, S_IRUGO, show_modalias, NULL), | |
218 | { }, | |
219 | }; | |
220 | ||
83eaaed0 | 221 | static struct bus_type i2c_bus_type = { |
f37dd80a | 222 | .name = "i2c", |
7b4fbc50 | 223 | .dev_attrs = i2c_dev_attrs, |
f37dd80a | 224 | .match = i2c_device_match, |
7b4fbc50 | 225 | .uevent = i2c_device_uevent, |
f37dd80a DB |
226 | .probe = i2c_device_probe, |
227 | .remove = i2c_device_remove, | |
228 | .shutdown = i2c_device_shutdown, | |
229 | .suspend = i2c_device_suspend, | |
230 | .resume = i2c_device_resume, | |
b864c7d5 RK |
231 | }; |
232 | ||
9b766b81 DB |
233 | |
234 | /** | |
235 | * i2c_verify_client - return parameter as i2c_client, or NULL | |
236 | * @dev: device, probably from some driver model iterator | |
237 | * | |
238 | * When traversing the driver model tree, perhaps using driver model | |
239 | * iterators like @device_for_each_child(), you can't assume very much | |
240 | * about the nodes you find. Use this function to avoid oopses caused | |
241 | * by wrongly treating some non-I2C device as an i2c_client. | |
242 | */ | |
243 | struct i2c_client *i2c_verify_client(struct device *dev) | |
244 | { | |
245 | return (dev->bus == &i2c_bus_type) | |
246 | ? to_i2c_client(dev) | |
247 | : NULL; | |
248 | } | |
249 | EXPORT_SYMBOL(i2c_verify_client); | |
250 | ||
251 | ||
9c1600ed DB |
252 | /** |
253 | * i2c_new_device - instantiate an i2c device for use with a new style driver | |
254 | * @adap: the adapter managing the device | |
255 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 256 | * Context: can sleep |
9c1600ed DB |
257 | * |
258 | * Create a device to work with a new style i2c driver, where binding is | |
259 | * handled through driver model probe()/remove() methods. This call is not | |
260 | * appropriate for use by mainboad initialization logic, which usually runs | |
261 | * during an arch_initcall() long before any i2c_adapter could exist. | |
262 | * | |
263 | * This returns the new i2c client, which may be saved for later use with | |
264 | * i2c_unregister_device(); or NULL to indicate an error. | |
265 | */ | |
266 | struct i2c_client * | |
267 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
268 | { | |
269 | struct i2c_client *client; | |
270 | int status; | |
271 | ||
272 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
273 | if (!client) | |
274 | return NULL; | |
275 | ||
276 | client->adapter = adap; | |
277 | ||
278 | client->dev.platform_data = info->platform_data; | |
3bbb835d DB |
279 | device_init_wakeup(&client->dev, info->flags & I2C_CLIENT_WAKE); |
280 | ||
281 | client->flags = info->flags & ~I2C_CLIENT_WAKE; | |
9c1600ed DB |
282 | client->addr = info->addr; |
283 | client->irq = info->irq; | |
284 | ||
285 | strlcpy(client->driver_name, info->driver_name, | |
286 | sizeof(client->driver_name)); | |
287 | strlcpy(client->name, info->type, sizeof(client->name)); | |
288 | ||
289 | /* a new style driver may be bound to this device when we | |
290 | * return from this function, or any later moment (e.g. maybe | |
291 | * hotplugging will load the driver module). and the device | |
292 | * refcount model is the standard driver model one. | |
293 | */ | |
294 | status = i2c_attach_client(client); | |
295 | if (status < 0) { | |
296 | kfree(client); | |
297 | client = NULL; | |
298 | } | |
299 | return client; | |
300 | } | |
301 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
302 | ||
303 | ||
304 | /** | |
305 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
306 | * @client: value returned from i2c_new_device() | |
d64f73be | 307 | * Context: can sleep |
9c1600ed DB |
308 | */ |
309 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 DB |
310 | { |
311 | struct i2c_adapter *adapter = client->adapter; | |
312 | struct i2c_driver *driver = client->driver; | |
313 | ||
314 | if (driver && !is_newstyle_driver(driver)) { | |
315 | dev_err(&client->dev, "can't unregister devices " | |
316 | "with legacy drivers\n"); | |
317 | WARN_ON(1); | |
318 | return; | |
319 | } | |
320 | ||
321 | mutex_lock(&adapter->clist_lock); | |
322 | list_del(&client->list); | |
323 | mutex_unlock(&adapter->clist_lock); | |
324 | ||
325 | device_unregister(&client->dev); | |
326 | } | |
9c1600ed | 327 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
328 | |
329 | ||
60b129d7 JD |
330 | static const struct i2c_device_id dummy_id[] = { |
331 | { "dummy", 0 }, | |
332 | { }, | |
333 | }; | |
334 | ||
d2653e92 JD |
335 | static int dummy_probe(struct i2c_client *client, |
336 | const struct i2c_device_id *id) | |
337 | { | |
338 | return 0; | |
339 | } | |
340 | ||
341 | static int dummy_remove(struct i2c_client *client) | |
e9f1373b DB |
342 | { |
343 | return 0; | |
344 | } | |
345 | ||
346 | static struct i2c_driver dummy_driver = { | |
347 | .driver.name = "dummy", | |
d2653e92 JD |
348 | .probe = dummy_probe, |
349 | .remove = dummy_remove, | |
60b129d7 | 350 | .id_table = dummy_id, |
e9f1373b DB |
351 | }; |
352 | ||
353 | /** | |
354 | * i2c_new_dummy - return a new i2c device bound to a dummy driver | |
355 | * @adapter: the adapter managing the device | |
356 | * @address: seven bit address to be used | |
e9f1373b DB |
357 | * Context: can sleep |
358 | * | |
359 | * This returns an I2C client bound to the "dummy" driver, intended for use | |
360 | * with devices that consume multiple addresses. Examples of such chips | |
361 | * include various EEPROMS (like 24c04 and 24c08 models). | |
362 | * | |
363 | * These dummy devices have two main uses. First, most I2C and SMBus calls | |
364 | * except i2c_transfer() need a client handle; the dummy will be that handle. | |
365 | * And second, this prevents the specified address from being bound to a | |
366 | * different driver. | |
367 | * | |
368 | * This returns the new i2c client, which should be saved for later use with | |
369 | * i2c_unregister_device(); or NULL to indicate an error. | |
370 | */ | |
371 | struct i2c_client * | |
60b129d7 | 372 | i2c_new_dummy(struct i2c_adapter *adapter, u16 address) |
e9f1373b DB |
373 | { |
374 | struct i2c_board_info info = { | |
60b129d7 | 375 | I2C_BOARD_INFO("dummy", address), |
e9f1373b DB |
376 | }; |
377 | ||
e9f1373b DB |
378 | return i2c_new_device(adapter, &info); |
379 | } | |
380 | EXPORT_SYMBOL_GPL(i2c_new_dummy); | |
381 | ||
f37dd80a DB |
382 | /* ------------------------------------------------------------------------- */ |
383 | ||
16ffadfc DB |
384 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
385 | ||
83eaaed0 | 386 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 387 | { |
ef2c8321 | 388 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
389 | complete(&adap->dev_released); |
390 | } | |
391 | ||
16ffadfc DB |
392 | static ssize_t |
393 | show_adapter_name(struct device *dev, struct device_attribute *attr, char *buf) | |
394 | { | |
ef2c8321 | 395 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
16ffadfc DB |
396 | return sprintf(buf, "%s\n", adap->name); |
397 | } | |
b119dc3f | 398 | |
16ffadfc DB |
399 | static struct device_attribute i2c_adapter_attrs[] = { |
400 | __ATTR(name, S_IRUGO, show_adapter_name, NULL), | |
401 | { }, | |
402 | }; | |
b119dc3f | 403 | |
83eaaed0 | 404 | static struct class i2c_adapter_class = { |
b119dc3f DB |
405 | .owner = THIS_MODULE, |
406 | .name = "i2c-adapter", | |
16ffadfc | 407 | .dev_attrs = i2c_adapter_attrs, |
1da177e4 LT |
408 | }; |
409 | ||
9c1600ed DB |
410 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
411 | { | |
412 | struct i2c_devinfo *devinfo; | |
413 | ||
414 | mutex_lock(&__i2c_board_lock); | |
415 | list_for_each_entry(devinfo, &__i2c_board_list, list) { | |
416 | if (devinfo->busnum == adapter->nr | |
417 | && !i2c_new_device(adapter, | |
418 | &devinfo->board_info)) | |
419 | printk(KERN_ERR "i2c-core: can't create i2c%d-%04x\n", | |
420 | i2c_adapter_id(adapter), | |
421 | devinfo->board_info.addr); | |
422 | } | |
423 | mutex_unlock(&__i2c_board_lock); | |
424 | } | |
425 | ||
026526f5 JD |
426 | static int i2c_do_add_adapter(struct device_driver *d, void *data) |
427 | { | |
428 | struct i2c_driver *driver = to_i2c_driver(d); | |
429 | struct i2c_adapter *adap = data; | |
430 | ||
431 | if (driver->attach_adapter) { | |
432 | /* We ignore the return code; if it fails, too bad */ | |
433 | driver->attach_adapter(adap); | |
434 | } | |
435 | return 0; | |
436 | } | |
437 | ||
6e13e641 | 438 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 439 | { |
026526f5 | 440 | int res = 0, dummy; |
1da177e4 | 441 | |
5c085d36 IM |
442 | mutex_init(&adap->bus_lock); |
443 | mutex_init(&adap->clist_lock); | |
1da177e4 LT |
444 | INIT_LIST_HEAD(&adap->clients); |
445 | ||
caada32a | 446 | mutex_lock(&core_lock); |
6e13e641 | 447 | |
1da177e4 LT |
448 | /* Add the adapter to the driver core. |
449 | * If the parent pointer is not set up, | |
450 | * we add this adapter to the host bus. | |
451 | */ | |
b119dc3f | 452 | if (adap->dev.parent == NULL) { |
1da177e4 | 453 | adap->dev.parent = &platform_bus; |
fe2c8d51 JD |
454 | pr_debug("I2C adapter driver [%s] forgot to specify " |
455 | "physical device\n", adap->name); | |
b119dc3f | 456 | } |
1da177e4 | 457 | sprintf(adap->dev.bus_id, "i2c-%d", adap->nr); |
1da177e4 | 458 | adap->dev.release = &i2c_adapter_dev_release; |
fccb56e4 | 459 | adap->dev.class = &i2c_adapter_class; |
b119c6c9 JD |
460 | res = device_register(&adap->dev); |
461 | if (res) | |
462 | goto out_list; | |
1da177e4 | 463 | |
b6d7b3d1 JD |
464 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
465 | ||
6e13e641 DB |
466 | /* create pre-declared device nodes for new-style drivers */ |
467 | if (adap->nr < __i2c_first_dynamic_bus_num) | |
468 | i2c_scan_static_board_info(adap); | |
469 | ||
7b4fbc50 | 470 | /* let legacy drivers scan this bus for matching devices */ |
026526f5 JD |
471 | dummy = bus_for_each_drv(&i2c_bus_type, NULL, adap, |
472 | i2c_do_add_adapter); | |
1da177e4 | 473 | |
1da177e4 | 474 | out_unlock: |
caada32a | 475 | mutex_unlock(&core_lock); |
1da177e4 | 476 | return res; |
b119c6c9 | 477 | |
b119c6c9 | 478 | out_list: |
b119c6c9 JD |
479 | idr_remove(&i2c_adapter_idr, adap->nr); |
480 | goto out_unlock; | |
1da177e4 LT |
481 | } |
482 | ||
6e13e641 DB |
483 | /** |
484 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
485 | * @adapter: the adapter to add | |
d64f73be | 486 | * Context: can sleep |
6e13e641 DB |
487 | * |
488 | * This routine is used to declare an I2C adapter when its bus number | |
489 | * doesn't matter. Examples: for I2C adapters dynamically added by | |
490 | * USB links or PCI plugin cards. | |
491 | * | |
492 | * When this returns zero, a new bus number was allocated and stored | |
493 | * in adap->nr, and the specified adapter became available for clients. | |
494 | * Otherwise, a negative errno value is returned. | |
495 | */ | |
496 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
497 | { | |
498 | int id, res = 0; | |
499 | ||
500 | retry: | |
501 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
502 | return -ENOMEM; | |
503 | ||
caada32a | 504 | mutex_lock(&core_lock); |
6e13e641 DB |
505 | /* "above" here means "above or equal to", sigh */ |
506 | res = idr_get_new_above(&i2c_adapter_idr, adapter, | |
507 | __i2c_first_dynamic_bus_num, &id); | |
caada32a | 508 | mutex_unlock(&core_lock); |
6e13e641 DB |
509 | |
510 | if (res < 0) { | |
511 | if (res == -EAGAIN) | |
512 | goto retry; | |
513 | return res; | |
514 | } | |
515 | ||
516 | adapter->nr = id; | |
517 | return i2c_register_adapter(adapter); | |
518 | } | |
519 | EXPORT_SYMBOL(i2c_add_adapter); | |
520 | ||
521 | /** | |
522 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
523 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 524 | * Context: can sleep |
6e13e641 DB |
525 | * |
526 | * This routine is used to declare an I2C adapter when its bus number | |
8c07e46f RD |
527 | * matters. For example, use it for I2C adapters from system-on-chip CPUs, |
528 | * or otherwise built in to the system's mainboard, and where i2c_board_info | |
6e13e641 DB |
529 | * is used to properly configure I2C devices. |
530 | * | |
531 | * If no devices have pre-been declared for this bus, then be sure to | |
532 | * register the adapter before any dynamically allocated ones. Otherwise | |
533 | * the required bus ID may not be available. | |
534 | * | |
535 | * When this returns zero, the specified adapter became available for | |
536 | * clients using the bus number provided in adap->nr. Also, the table | |
537 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
538 | * and the appropriate driver model device nodes are created. Otherwise, a | |
539 | * negative errno value is returned. | |
540 | */ | |
541 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
542 | { | |
543 | int id; | |
544 | int status; | |
545 | ||
546 | if (adap->nr & ~MAX_ID_MASK) | |
547 | return -EINVAL; | |
548 | ||
549 | retry: | |
550 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
551 | return -ENOMEM; | |
552 | ||
caada32a | 553 | mutex_lock(&core_lock); |
6e13e641 DB |
554 | /* "above" here means "above or equal to", sigh; |
555 | * we need the "equal to" result to force the result | |
556 | */ | |
557 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); | |
558 | if (status == 0 && id != adap->nr) { | |
559 | status = -EBUSY; | |
560 | idr_remove(&i2c_adapter_idr, id); | |
561 | } | |
caada32a | 562 | mutex_unlock(&core_lock); |
6e13e641 DB |
563 | if (status == -EAGAIN) |
564 | goto retry; | |
565 | ||
566 | if (status == 0) | |
567 | status = i2c_register_adapter(adap); | |
568 | return status; | |
569 | } | |
570 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
571 | ||
026526f5 JD |
572 | static int i2c_do_del_adapter(struct device_driver *d, void *data) |
573 | { | |
574 | struct i2c_driver *driver = to_i2c_driver(d); | |
575 | struct i2c_adapter *adapter = data; | |
576 | int res; | |
577 | ||
578 | if (!driver->detach_adapter) | |
579 | return 0; | |
580 | res = driver->detach_adapter(adapter); | |
581 | if (res) | |
582 | dev_err(&adapter->dev, "detach_adapter failed (%d) " | |
583 | "for driver [%s]\n", res, driver->driver.name); | |
584 | return res; | |
585 | } | |
586 | ||
d64f73be DB |
587 | /** |
588 | * i2c_del_adapter - unregister I2C adapter | |
589 | * @adap: the adapter being unregistered | |
590 | * Context: can sleep | |
591 | * | |
592 | * This unregisters an I2C adapter which was previously registered | |
593 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
594 | */ | |
1da177e4 LT |
595 | int i2c_del_adapter(struct i2c_adapter *adap) |
596 | { | |
597 | struct list_head *item, *_n; | |
1da177e4 LT |
598 | struct i2c_client *client; |
599 | int res = 0; | |
600 | ||
caada32a | 601 | mutex_lock(&core_lock); |
1da177e4 LT |
602 | |
603 | /* First make sure that this adapter was ever added */ | |
87c6c229 | 604 | if (idr_find(&i2c_adapter_idr, adap->nr) != adap) { |
b6d7b3d1 JD |
605 | pr_debug("i2c-core: attempting to delete unregistered " |
606 | "adapter [%s]\n", adap->name); | |
1da177e4 LT |
607 | res = -EINVAL; |
608 | goto out_unlock; | |
609 | } | |
610 | ||
026526f5 JD |
611 | /* Tell drivers about this removal */ |
612 | res = bus_for_each_drv(&i2c_bus_type, NULL, adap, | |
613 | i2c_do_del_adapter); | |
614 | if (res) | |
615 | goto out_unlock; | |
1da177e4 LT |
616 | |
617 | /* detach any active clients. This must be done first, because | |
a551acc2 | 618 | * it can fail; in which case we give up. */ |
1da177e4 | 619 | list_for_each_safe(item, _n, &adap->clients) { |
a1d9e6e4 DB |
620 | struct i2c_driver *driver; |
621 | ||
1da177e4 | 622 | client = list_entry(item, struct i2c_client, list); |
a1d9e6e4 DB |
623 | driver = client->driver; |
624 | ||
625 | /* new style, follow standard driver model */ | |
626 | if (!driver || is_newstyle_driver(driver)) { | |
627 | i2c_unregister_device(client); | |
628 | continue; | |
629 | } | |
1da177e4 | 630 | |
a1d9e6e4 DB |
631 | /* legacy drivers create and remove clients themselves */ |
632 | if ((res = driver->detach_client(client))) { | |
b6d7b3d1 JD |
633 | dev_err(&adap->dev, "detach_client failed for client " |
634 | "[%s] at address 0x%02x\n", client->name, | |
1da177e4 LT |
635 | client->addr); |
636 | goto out_unlock; | |
637 | } | |
638 | } | |
639 | ||
640 | /* clean up the sysfs representation */ | |
641 | init_completion(&adap->dev_released); | |
1da177e4 | 642 | device_unregister(&adap->dev); |
1da177e4 LT |
643 | |
644 | /* wait for sysfs to drop all references */ | |
645 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 646 | |
6e13e641 | 647 | /* free bus id */ |
1da177e4 LT |
648 | idr_remove(&i2c_adapter_idr, adap->nr); |
649 | ||
b6d7b3d1 | 650 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); |
1da177e4 LT |
651 | |
652 | out_unlock: | |
caada32a | 653 | mutex_unlock(&core_lock); |
1da177e4 LT |
654 | return res; |
655 | } | |
c0564606 | 656 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 LT |
657 | |
658 | ||
7b4fbc50 DB |
659 | /* ------------------------------------------------------------------------- */ |
660 | ||
661 | /* | |
662 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
663 | * i2c slave chips, on a bus instance associated with some i2c_adapter. There | |
664 | * are two models for binding the driver to its device: "new style" drivers | |
665 | * follow the standard Linux driver model and just respond to probe() calls | |
666 | * issued if the driver core sees they match(); "legacy" drivers create device | |
667 | * nodes themselves. | |
1da177e4 LT |
668 | */ |
669 | ||
de59cf9e | 670 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 671 | { |
7eebcb7c | 672 | int res; |
1da177e4 | 673 | |
7b4fbc50 | 674 | /* new style driver methods can't mix with legacy ones */ |
a1d9e6e4 | 675 | if (is_newstyle_driver(driver)) { |
7b4fbc50 DB |
676 | if (driver->attach_adapter || driver->detach_adapter |
677 | || driver->detach_client) { | |
678 | printk(KERN_WARNING | |
679 | "i2c-core: driver [%s] is confused\n", | |
680 | driver->driver.name); | |
681 | return -EINVAL; | |
682 | } | |
683 | } | |
684 | ||
1da177e4 | 685 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 686 | driver->driver.owner = owner; |
1da177e4 | 687 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 688 | |
6e13e641 DB |
689 | /* for new style drivers, when registration returns the driver core |
690 | * will have called probe() for all matching-but-unbound devices. | |
691 | */ | |
1da177e4 LT |
692 | res = driver_register(&driver->driver); |
693 | if (res) | |
7eebcb7c | 694 | return res; |
438d6c2c | 695 | |
caada32a | 696 | mutex_lock(&core_lock); |
7eebcb7c | 697 | |
35d8b2e6 | 698 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 699 | |
7b4fbc50 | 700 | /* legacy drivers scan i2c busses directly */ |
8a994755 | 701 | if (driver->attach_adapter) { |
4ad4eac6 DB |
702 | struct i2c_adapter *adapter; |
703 | ||
87c6c229 JD |
704 | down(&i2c_adapter_class.sem); |
705 | list_for_each_entry(adapter, &i2c_adapter_class.devices, | |
706 | dev.node) { | |
1da177e4 LT |
707 | driver->attach_adapter(adapter); |
708 | } | |
87c6c229 | 709 | up(&i2c_adapter_class.sem); |
1da177e4 LT |
710 | } |
711 | ||
caada32a | 712 | mutex_unlock(&core_lock); |
7eebcb7c | 713 | return 0; |
1da177e4 | 714 | } |
de59cf9e | 715 | EXPORT_SYMBOL(i2c_register_driver); |
1da177e4 | 716 | |
a1d9e6e4 DB |
717 | /** |
718 | * i2c_del_driver - unregister I2C driver | |
719 | * @driver: the driver being unregistered | |
d64f73be | 720 | * Context: can sleep |
a1d9e6e4 | 721 | */ |
b3e82096 | 722 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 | 723 | { |
87c6c229 | 724 | struct list_head *item2, *_n; |
1da177e4 LT |
725 | struct i2c_client *client; |
726 | struct i2c_adapter *adap; | |
438d6c2c | 727 | |
caada32a | 728 | mutex_lock(&core_lock); |
1da177e4 | 729 | |
a1d9e6e4 DB |
730 | /* new-style driver? */ |
731 | if (is_newstyle_driver(driver)) | |
732 | goto unregister; | |
733 | ||
1da177e4 | 734 | /* Have a look at each adapter, if clients of this driver are still |
438d6c2c | 735 | * attached. If so, detach them to be able to kill the driver |
1da177e4 | 736 | * afterwards. |
1da177e4 | 737 | */ |
87c6c229 JD |
738 | down(&i2c_adapter_class.sem); |
739 | list_for_each_entry(adap, &i2c_adapter_class.devices, dev.node) { | |
1da177e4 | 740 | if (driver->detach_adapter) { |
b3e82096 | 741 | if (driver->detach_adapter(adap)) { |
b6d7b3d1 | 742 | dev_err(&adap->dev, "detach_adapter failed " |
35d8b2e6 LR |
743 | "for driver [%s]\n", |
744 | driver->driver.name); | |
1da177e4 LT |
745 | } |
746 | } else { | |
747 | list_for_each_safe(item2, _n, &adap->clients) { | |
748 | client = list_entry(item2, struct i2c_client, list); | |
749 | if (client->driver != driver) | |
750 | continue; | |
b6d7b3d1 JD |
751 | dev_dbg(&adap->dev, "detaching client [%s] " |
752 | "at 0x%02x\n", client->name, | |
753 | client->addr); | |
b3e82096 | 754 | if (driver->detach_client(client)) { |
b6d7b3d1 JD |
755 | dev_err(&adap->dev, "detach_client " |
756 | "failed for client [%s] at " | |
757 | "0x%02x\n", client->name, | |
1da177e4 | 758 | client->addr); |
1da177e4 LT |
759 | } |
760 | } | |
761 | } | |
762 | } | |
87c6c229 | 763 | up(&i2c_adapter_class.sem); |
1da177e4 | 764 | |
a1d9e6e4 | 765 | unregister: |
1da177e4 | 766 | driver_unregister(&driver->driver); |
35d8b2e6 | 767 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 768 | |
caada32a | 769 | mutex_unlock(&core_lock); |
1da177e4 | 770 | } |
c0564606 | 771 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 772 | |
7b4fbc50 DB |
773 | /* ------------------------------------------------------------------------- */ |
774 | ||
9b766b81 | 775 | static int __i2c_check_addr(struct device *dev, void *addrp) |
1da177e4 | 776 | { |
9b766b81 DB |
777 | struct i2c_client *client = i2c_verify_client(dev); |
778 | int addr = *(int *)addrp; | |
1da177e4 | 779 | |
9b766b81 DB |
780 | if (client && client->addr == addr) |
781 | return -EBUSY; | |
1da177e4 LT |
782 | return 0; |
783 | } | |
784 | ||
5e31c2bd | 785 | static int i2c_check_addr(struct i2c_adapter *adapter, int addr) |
1da177e4 | 786 | { |
9b766b81 | 787 | return device_for_each_child(&adapter->dev, &addr, __i2c_check_addr); |
1da177e4 LT |
788 | } |
789 | ||
790 | int i2c_attach_client(struct i2c_client *client) | |
791 | { | |
792 | struct i2c_adapter *adapter = client->adapter; | |
b119c6c9 | 793 | int res = 0; |
1da177e4 | 794 | |
1da177e4 | 795 | client->dev.parent = &client->adapter->dev; |
1da177e4 | 796 | client->dev.bus = &i2c_bus_type; |
9c1600ed DB |
797 | |
798 | if (client->driver) | |
799 | client->dev.driver = &client->driver->driver; | |
800 | ||
de81d2aa | 801 | if (client->driver && !is_newstyle_driver(client->driver)) { |
9c1600ed | 802 | client->dev.release = i2c_client_release; |
de81d2aa DB |
803 | client->dev.uevent_suppress = 1; |
804 | } else | |
9c1600ed | 805 | client->dev.release = i2c_client_dev_release; |
438d6c2c | 806 | |
1da177e4 LT |
807 | snprintf(&client->dev.bus_id[0], sizeof(client->dev.bus_id), |
808 | "%d-%04x", i2c_adapter_id(adapter), client->addr); | |
b119c6c9 JD |
809 | res = device_register(&client->dev); |
810 | if (res) | |
86ec5ec8 DB |
811 | goto out_err; |
812 | ||
813 | mutex_lock(&adapter->clist_lock); | |
814 | list_add_tail(&client->list, &adapter->clients); | |
b119c6c9 | 815 | mutex_unlock(&adapter->clist_lock); |
77ed74da | 816 | |
86ec5ec8 DB |
817 | dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n", |
818 | client->name, client->dev.bus_id); | |
819 | ||
77ed74da JD |
820 | if (adapter->client_register) { |
821 | if (adapter->client_register(client)) { | |
822 | dev_dbg(&adapter->dev, "client_register " | |
823 | "failed for client [%s] at 0x%02x\n", | |
824 | client->name, client->addr); | |
825 | } | |
826 | } | |
827 | ||
828 | return 0; | |
b119c6c9 | 829 | |
86ec5ec8 | 830 | out_err: |
b119c6c9 JD |
831 | dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x " |
832 | "(%d)\n", client->name, client->addr, res); | |
77ed74da | 833 | return res; |
1da177e4 | 834 | } |
c0564606 | 835 | EXPORT_SYMBOL(i2c_attach_client); |
1da177e4 LT |
836 | |
837 | int i2c_detach_client(struct i2c_client *client) | |
838 | { | |
839 | struct i2c_adapter *adapter = client->adapter; | |
840 | int res = 0; | |
438d6c2c | 841 | |
1da177e4 LT |
842 | if (adapter->client_unregister) { |
843 | res = adapter->client_unregister(client); | |
844 | if (res) { | |
845 | dev_err(&client->dev, | |
86749e85 JD |
846 | "client_unregister [%s] failed, " |
847 | "client not detached\n", client->name); | |
1da177e4 LT |
848 | goto out; |
849 | } | |
850 | } | |
851 | ||
5c085d36 | 852 | mutex_lock(&adapter->clist_lock); |
1da177e4 | 853 | list_del(&client->list); |
9ddced16 JD |
854 | mutex_unlock(&adapter->clist_lock); |
855 | ||
1da177e4 | 856 | init_completion(&client->released); |
1da177e4 | 857 | device_unregister(&client->dev); |
1da177e4 LT |
858 | wait_for_completion(&client->released); |
859 | ||
860 | out: | |
861 | return res; | |
862 | } | |
c0564606 | 863 | EXPORT_SYMBOL(i2c_detach_client); |
1da177e4 | 864 | |
e48d3319 JD |
865 | /** |
866 | * i2c_use_client - increments the reference count of the i2c client structure | |
867 | * @client: the client being referenced | |
868 | * | |
869 | * Each live reference to a client should be refcounted. The driver model does | |
870 | * that automatically as part of driver binding, so that most drivers don't | |
871 | * need to do this explicitly: they hold a reference until they're unbound | |
872 | * from the device. | |
873 | * | |
874 | * A pointer to the client with the incremented reference counter is returned. | |
875 | */ | |
876 | struct i2c_client *i2c_use_client(struct i2c_client *client) | |
1da177e4 | 877 | { |
bdc511f4 | 878 | get_device(&client->dev); |
e48d3319 | 879 | return client; |
1da177e4 | 880 | } |
c0564606 | 881 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 | 882 | |
e48d3319 JD |
883 | /** |
884 | * i2c_release_client - release a use of the i2c client structure | |
885 | * @client: the client being no longer referenced | |
886 | * | |
887 | * Must be called when a user of a client is finished with it. | |
888 | */ | |
889 | void i2c_release_client(struct i2c_client *client) | |
1da177e4 | 890 | { |
bdc511f4 | 891 | put_device(&client->dev); |
1da177e4 | 892 | } |
c0564606 | 893 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 | 894 | |
9b766b81 DB |
895 | struct i2c_cmd_arg { |
896 | unsigned cmd; | |
897 | void *arg; | |
898 | }; | |
899 | ||
900 | static int i2c_cmd(struct device *dev, void *_arg) | |
901 | { | |
902 | struct i2c_client *client = i2c_verify_client(dev); | |
903 | struct i2c_cmd_arg *arg = _arg; | |
904 | ||
905 | if (client && client->driver && client->driver->command) | |
906 | client->driver->command(client, arg->cmd, arg->arg); | |
907 | return 0; | |
908 | } | |
909 | ||
1da177e4 LT |
910 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) |
911 | { | |
9b766b81 | 912 | struct i2c_cmd_arg cmd_arg; |
1da177e4 | 913 | |
9b766b81 DB |
914 | cmd_arg.cmd = cmd; |
915 | cmd_arg.arg = arg; | |
916 | device_for_each_child(&adap->dev, &cmd_arg, i2c_cmd); | |
1da177e4 | 917 | } |
c0564606 | 918 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
919 | |
920 | static int __init i2c_init(void) | |
921 | { | |
922 | int retval; | |
923 | ||
924 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
925 | if (retval) |
926 | return retval; | |
e9f1373b DB |
927 | retval = class_register(&i2c_adapter_class); |
928 | if (retval) | |
929 | goto bus_err; | |
930 | retval = i2c_add_driver(&dummy_driver); | |
931 | if (retval) | |
932 | goto class_err; | |
933 | return 0; | |
934 | ||
935 | class_err: | |
936 | class_unregister(&i2c_adapter_class); | |
937 | bus_err: | |
938 | bus_unregister(&i2c_bus_type); | |
939 | return retval; | |
1da177e4 LT |
940 | } |
941 | ||
942 | static void __exit i2c_exit(void) | |
943 | { | |
e9f1373b | 944 | i2c_del_driver(&dummy_driver); |
1da177e4 | 945 | class_unregister(&i2c_adapter_class); |
1da177e4 LT |
946 | bus_unregister(&i2c_bus_type); |
947 | } | |
948 | ||
949 | subsys_initcall(i2c_init); | |
950 | module_exit(i2c_exit); | |
951 | ||
952 | /* ---------------------------------------------------- | |
953 | * the functional interface to the i2c busses. | |
954 | * ---------------------------------------------------- | |
955 | */ | |
956 | ||
957 | int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num) | |
958 | { | |
959 | int ret; | |
960 | ||
961 | if (adap->algo->master_xfer) { | |
962 | #ifdef DEBUG | |
963 | for (ret = 0; ret < num; ret++) { | |
964 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
965 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
966 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
967 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
968 | } |
969 | #endif | |
970 | ||
cea443a8 MR |
971 | if (in_atomic() || irqs_disabled()) { |
972 | ret = mutex_trylock(&adap->bus_lock); | |
973 | if (!ret) | |
974 | /* I2C activity is ongoing. */ | |
975 | return -EAGAIN; | |
976 | } else { | |
977 | mutex_lock_nested(&adap->bus_lock, adap->level); | |
978 | } | |
979 | ||
1da177e4 | 980 | ret = adap->algo->master_xfer(adap,msgs,num); |
5c085d36 | 981 | mutex_unlock(&adap->bus_lock); |
1da177e4 LT |
982 | |
983 | return ret; | |
984 | } else { | |
985 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
986 | return -ENOSYS; | |
987 | } | |
988 | } | |
c0564606 | 989 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 LT |
990 | |
991 | int i2c_master_send(struct i2c_client *client,const char *buf ,int count) | |
992 | { | |
993 | int ret; | |
994 | struct i2c_adapter *adap=client->adapter; | |
995 | struct i2c_msg msg; | |
996 | ||
815f55f2 JD |
997 | msg.addr = client->addr; |
998 | msg.flags = client->flags & I2C_M_TEN; | |
999 | msg.len = count; | |
1000 | msg.buf = (char *)buf; | |
438d6c2c | 1001 | |
815f55f2 | 1002 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 1003 | |
815f55f2 JD |
1004 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
1005 | transmitted, else error code. */ | |
1006 | return (ret == 1) ? count : ret; | |
1da177e4 | 1007 | } |
c0564606 | 1008 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 LT |
1009 | |
1010 | int i2c_master_recv(struct i2c_client *client, char *buf ,int count) | |
1011 | { | |
1012 | struct i2c_adapter *adap=client->adapter; | |
1013 | struct i2c_msg msg; | |
1014 | int ret; | |
815f55f2 JD |
1015 | |
1016 | msg.addr = client->addr; | |
1017 | msg.flags = client->flags & I2C_M_TEN; | |
1018 | msg.flags |= I2C_M_RD; | |
1019 | msg.len = count; | |
1020 | msg.buf = buf; | |
1021 | ||
1022 | ret = i2c_transfer(adap, &msg, 1); | |
1023 | ||
1024 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes | |
1025 | transmitted, else error code. */ | |
1026 | return (ret == 1) ? count : ret; | |
1da177e4 | 1027 | } |
c0564606 | 1028 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 1029 | |
1da177e4 LT |
1030 | /* ---------------------------------------------------- |
1031 | * the i2c address scanning function | |
1032 | * Will not work for 10-bit addresses! | |
1033 | * ---------------------------------------------------- | |
1034 | */ | |
a89ba0bc JD |
1035 | static int i2c_probe_address(struct i2c_adapter *adapter, int addr, int kind, |
1036 | int (*found_proc) (struct i2c_adapter *, int, int)) | |
1037 | { | |
1038 | int err; | |
1039 | ||
1040 | /* Make sure the address is valid */ | |
1041 | if (addr < 0x03 || addr > 0x77) { | |
1042 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", | |
1043 | addr); | |
1044 | return -EINVAL; | |
9fc6adfa JD |
1045 | } |
1046 | ||
a89ba0bc JD |
1047 | /* Skip if already in use */ |
1048 | if (i2c_check_addr(adapter, addr)) | |
1049 | return 0; | |
1050 | ||
1051 | /* Make sure there is something at this address, unless forced */ | |
4c9337da JD |
1052 | if (kind < 0) { |
1053 | if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, | |
1054 | I2C_SMBUS_QUICK, NULL) < 0) | |
1055 | return 0; | |
1056 | ||
1057 | /* prevent 24RF08 corruption */ | |
1058 | if ((addr & ~0x0f) == 0x50) | |
1059 | i2c_smbus_xfer(adapter, addr, 0, 0, 0, | |
1060 | I2C_SMBUS_QUICK, NULL); | |
1061 | } | |
a89ba0bc JD |
1062 | |
1063 | /* Finally call the custom detection function */ | |
1064 | err = found_proc(adapter, addr, kind); | |
a89ba0bc JD |
1065 | /* -ENODEV can be returned if there is a chip at the given address |
1066 | but it isn't supported by this chip driver. We catch it here as | |
1067 | this isn't an error. */ | |
114fd183 JD |
1068 | if (err == -ENODEV) |
1069 | err = 0; | |
1070 | ||
1071 | if (err) | |
1072 | dev_warn(&adapter->dev, "Client creation failed at 0x%x (%d)\n", | |
1073 | addr, err); | |
1074 | return err; | |
9fc6adfa JD |
1075 | } |
1076 | ||
1da177e4 | 1077 | int i2c_probe(struct i2c_adapter *adapter, |
bfb6df24 | 1078 | const struct i2c_client_address_data *address_data, |
1da177e4 LT |
1079 | int (*found_proc) (struct i2c_adapter *, int, int)) |
1080 | { | |
a89ba0bc | 1081 | int i, err; |
1da177e4 LT |
1082 | int adap_id = i2c_adapter_id(adapter); |
1083 | ||
a89ba0bc JD |
1084 | /* Force entries are done first, and are not affected by ignore |
1085 | entries */ | |
1086 | if (address_data->forces) { | |
bfb6df24 | 1087 | const unsigned short * const *forces = address_data->forces; |
a89ba0bc JD |
1088 | int kind; |
1089 | ||
1090 | for (kind = 0; forces[kind]; kind++) { | |
1091 | for (i = 0; forces[kind][i] != I2C_CLIENT_END; | |
1092 | i += 2) { | |
1093 | if (forces[kind][i] == adap_id | |
1094 | || forces[kind][i] == ANY_I2C_BUS) { | |
1095 | dev_dbg(&adapter->dev, "found force " | |
1096 | "parameter for adapter %d, " | |
1097 | "addr 0x%02x, kind %d\n", | |
1098 | adap_id, forces[kind][i + 1], | |
1099 | kind); | |
1100 | err = i2c_probe_address(adapter, | |
1101 | forces[kind][i + 1], | |
1102 | kind, found_proc); | |
1103 | if (err) | |
1104 | return err; | |
1105 | } | |
1da177e4 LT |
1106 | } |
1107 | } | |
a89ba0bc | 1108 | } |
1da177e4 | 1109 | |
4366dc94 JD |
1110 | /* Stop here if we can't use SMBUS_QUICK */ |
1111 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) { | |
1112 | if (address_data->probe[0] == I2C_CLIENT_END | |
1113 | && address_data->normal_i2c[0] == I2C_CLIENT_END) | |
438d6c2c | 1114 | return 0; |
4366dc94 JD |
1115 | |
1116 | dev_warn(&adapter->dev, "SMBus Quick command not supported, " | |
1117 | "can't probe for chips\n"); | |
1118 | return -1; | |
1119 | } | |
1120 | ||
a89ba0bc JD |
1121 | /* Probe entries are done second, and are not affected by ignore |
1122 | entries either */ | |
1123 | for (i = 0; address_data->probe[i] != I2C_CLIENT_END; i += 2) { | |
1124 | if (address_data->probe[i] == adap_id | |
1125 | || address_data->probe[i] == ANY_I2C_BUS) { | |
1126 | dev_dbg(&adapter->dev, "found probe parameter for " | |
1127 | "adapter %d, addr 0x%02x\n", adap_id, | |
1128 | address_data->probe[i + 1]); | |
1129 | err = i2c_probe_address(adapter, | |
1130 | address_data->probe[i + 1], | |
1131 | -1, found_proc); | |
1132 | if (err) | |
1133 | return err; | |
1da177e4 | 1134 | } |
a89ba0bc | 1135 | } |
1da177e4 | 1136 | |
a89ba0bc JD |
1137 | /* Normal entries are done last, unless shadowed by an ignore entry */ |
1138 | for (i = 0; address_data->normal_i2c[i] != I2C_CLIENT_END; i += 1) { | |
1139 | int j, ignore; | |
1140 | ||
1141 | ignore = 0; | |
1142 | for (j = 0; address_data->ignore[j] != I2C_CLIENT_END; | |
1143 | j += 2) { | |
1144 | if ((address_data->ignore[j] == adap_id || | |
1145 | address_data->ignore[j] == ANY_I2C_BUS) | |
1146 | && address_data->ignore[j + 1] | |
1147 | == address_data->normal_i2c[i]) { | |
1148 | dev_dbg(&adapter->dev, "found ignore " | |
1149 | "parameter for adapter %d, " | |
1150 | "addr 0x%02x\n", adap_id, | |
1151 | address_data->ignore[j + 1]); | |
2369df93 MH |
1152 | ignore = 1; |
1153 | break; | |
1da177e4 LT |
1154 | } |
1155 | } | |
a89ba0bc | 1156 | if (ignore) |
1da177e4 LT |
1157 | continue; |
1158 | ||
a89ba0bc JD |
1159 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
1160 | "addr 0x%02x\n", adap_id, | |
1161 | address_data->normal_i2c[i]); | |
1162 | err = i2c_probe_address(adapter, address_data->normal_i2c[i], | |
1163 | -1, found_proc); | |
1164 | if (err) | |
1165 | return err; | |
1da177e4 | 1166 | } |
a89ba0bc | 1167 | |
1da177e4 LT |
1168 | return 0; |
1169 | } | |
c0564606 | 1170 | EXPORT_SYMBOL(i2c_probe); |
1da177e4 | 1171 | |
12b5053a JD |
1172 | struct i2c_client * |
1173 | i2c_new_probed_device(struct i2c_adapter *adap, | |
1174 | struct i2c_board_info *info, | |
1175 | unsigned short const *addr_list) | |
1176 | { | |
1177 | int i; | |
1178 | ||
1179 | /* Stop here if the bus doesn't support probing */ | |
1180 | if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) { | |
1181 | dev_err(&adap->dev, "Probing not supported\n"); | |
1182 | return NULL; | |
1183 | } | |
1184 | ||
12b5053a JD |
1185 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { |
1186 | /* Check address validity */ | |
1187 | if (addr_list[i] < 0x03 || addr_list[i] > 0x77) { | |
1188 | dev_warn(&adap->dev, "Invalid 7-bit address " | |
1189 | "0x%02x\n", addr_list[i]); | |
1190 | continue; | |
1191 | } | |
1192 | ||
1193 | /* Check address availability */ | |
9b766b81 | 1194 | if (i2c_check_addr(adap, addr_list[i])) { |
12b5053a JD |
1195 | dev_dbg(&adap->dev, "Address 0x%02x already in " |
1196 | "use, not probing\n", addr_list[i]); | |
1197 | continue; | |
1198 | } | |
1199 | ||
1200 | /* Test address responsiveness | |
1201 | The default probe method is a quick write, but it is known | |
1202 | to corrupt the 24RF08 EEPROMs due to a state machine bug, | |
1203 | and could also irreversibly write-protect some EEPROMs, so | |
1204 | for address ranges 0x30-0x37 and 0x50-0x5f, we use a byte | |
1205 | read instead. Also, some bus drivers don't implement | |
1206 | quick write, so we fallback to a byte read it that case | |
1207 | too. */ | |
1208 | if ((addr_list[i] & ~0x07) == 0x30 | |
1209 | || (addr_list[i] & ~0x0f) == 0x50 | |
1210 | || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) { | |
1211 | if (i2c_smbus_xfer(adap, addr_list[i], 0, | |
1212 | I2C_SMBUS_READ, 0, | |
1213 | I2C_SMBUS_BYTE, NULL) >= 0) | |
1214 | break; | |
1215 | } else { | |
1216 | if (i2c_smbus_xfer(adap, addr_list[i], 0, | |
1217 | I2C_SMBUS_WRITE, 0, | |
1218 | I2C_SMBUS_QUICK, NULL) >= 0) | |
1219 | break; | |
1220 | } | |
1221 | } | |
12b5053a JD |
1222 | |
1223 | if (addr_list[i] == I2C_CLIENT_END) { | |
1224 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
1225 | return NULL; | |
1226 | } | |
1227 | ||
1228 | info->addr = addr_list[i]; | |
1229 | return i2c_new_device(adap, info); | |
1230 | } | |
1231 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
1232 | ||
1da177e4 LT |
1233 | struct i2c_adapter* i2c_get_adapter(int id) |
1234 | { | |
1da177e4 | 1235 | struct i2c_adapter *adapter; |
438d6c2c | 1236 | |
caada32a | 1237 | mutex_lock(&core_lock); |
a0920e10 MH |
1238 | adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id); |
1239 | if (adapter && !try_module_get(adapter->owner)) | |
1240 | adapter = NULL; | |
1241 | ||
caada32a | 1242 | mutex_unlock(&core_lock); |
a0920e10 | 1243 | return adapter; |
1da177e4 | 1244 | } |
c0564606 | 1245 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
1246 | |
1247 | void i2c_put_adapter(struct i2c_adapter *adap) | |
1248 | { | |
1249 | module_put(adap->owner); | |
1250 | } | |
c0564606 | 1251 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
1252 | |
1253 | /* The SMBus parts */ | |
1254 | ||
438d6c2c | 1255 | #define POLY (0x1070U << 3) |
1da177e4 LT |
1256 | static u8 |
1257 | crc8(u16 data) | |
1258 | { | |
1259 | int i; | |
438d6c2c | 1260 | |
1da177e4 | 1261 | for(i = 0; i < 8; i++) { |
438d6c2c | 1262 | if (data & 0x8000) |
1da177e4 LT |
1263 | data = data ^ POLY; |
1264 | data = data << 1; | |
1265 | } | |
1266 | return (u8)(data >> 8); | |
1267 | } | |
1268 | ||
421ef47b JD |
1269 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
1270 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
1271 | { |
1272 | int i; | |
1273 | ||
1274 | for(i = 0; i < count; i++) | |
421ef47b | 1275 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
1276 | return crc; |
1277 | } | |
1278 | ||
421ef47b JD |
1279 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
1280 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 1281 | { |
421ef47b JD |
1282 | /* The address will be sent first */ |
1283 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
1284 | pec = i2c_smbus_pec(pec, &addr, 1); | |
1285 | ||
1286 | /* The data buffer follows */ | |
1287 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
1288 | } |
1289 | ||
421ef47b JD |
1290 | /* Used for write only transactions */ |
1291 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 1292 | { |
421ef47b JD |
1293 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
1294 | msg->len++; | |
1da177e4 LT |
1295 | } |
1296 | ||
421ef47b JD |
1297 | /* Return <0 on CRC error |
1298 | If there was a write before this read (most cases) we need to take the | |
1299 | partial CRC from the write part into account. | |
1300 | Note that this function does modify the message (we need to decrease the | |
1301 | message length to hide the CRC byte from the caller). */ | |
1302 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 1303 | { |
421ef47b JD |
1304 | u8 rpec = msg->buf[--msg->len]; |
1305 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 1306 | |
1da177e4 LT |
1307 | if (rpec != cpec) { |
1308 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
1309 | rpec, cpec); | |
1310 | return -1; | |
1311 | } | |
438d6c2c | 1312 | return 0; |
1da177e4 LT |
1313 | } |
1314 | ||
1315 | s32 i2c_smbus_write_quick(struct i2c_client *client, u8 value) | |
1316 | { | |
1317 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
438d6c2c | 1318 | value,0,I2C_SMBUS_QUICK,NULL); |
1da177e4 | 1319 | } |
c0564606 | 1320 | EXPORT_SYMBOL(i2c_smbus_write_quick); |
1da177e4 LT |
1321 | |
1322 | s32 i2c_smbus_read_byte(struct i2c_client *client) | |
1323 | { | |
1324 | union i2c_smbus_data data; | |
1325 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1326 | I2C_SMBUS_READ,0,I2C_SMBUS_BYTE, &data)) | |
1327 | return -1; | |
1328 | else | |
7eff82c8 | 1329 | return data.byte; |
1da177e4 | 1330 | } |
c0564606 | 1331 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 LT |
1332 | |
1333 | s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) | |
1334 | { | |
1da177e4 | 1335 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
421ef47b | 1336 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 1337 | } |
c0564606 | 1338 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 LT |
1339 | |
1340 | s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) | |
1341 | { | |
1342 | union i2c_smbus_data data; | |
1343 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1344 | I2C_SMBUS_READ,command, I2C_SMBUS_BYTE_DATA,&data)) | |
1345 | return -1; | |
1346 | else | |
7eff82c8 | 1347 | return data.byte; |
1da177e4 | 1348 | } |
c0564606 | 1349 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 LT |
1350 | |
1351 | s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value) | |
1352 | { | |
1353 | union i2c_smbus_data data; | |
1354 | data.byte = value; | |
1355 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1356 | I2C_SMBUS_WRITE,command, | |
1357 | I2C_SMBUS_BYTE_DATA,&data); | |
1358 | } | |
c0564606 | 1359 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 LT |
1360 | |
1361 | s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command) | |
1362 | { | |
1363 | union i2c_smbus_data data; | |
1364 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1365 | I2C_SMBUS_READ,command, I2C_SMBUS_WORD_DATA, &data)) | |
1366 | return -1; | |
1367 | else | |
7eff82c8 | 1368 | return data.word; |
1da177e4 | 1369 | } |
c0564606 | 1370 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 LT |
1371 | |
1372 | s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value) | |
1373 | { | |
1374 | union i2c_smbus_data data; | |
1375 | data.word = value; | |
1376 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1377 | I2C_SMBUS_WRITE,command, | |
1378 | I2C_SMBUS_WORD_DATA,&data); | |
1379 | } | |
c0564606 | 1380 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 1381 | |
a64ec07d DB |
1382 | /** |
1383 | * i2c_smbus_read_block_data - SMBus block read request | |
1384 | * @client: Handle to slave device | |
1385 | * @command: Command byte issued to let the slave know what data should | |
1386 | * be returned | |
1387 | * @values: Byte array into which data will be read; big enough to hold | |
1388 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
1389 | * | |
1390 | * Returns the number of bytes read in the slave's response, else a | |
1391 | * negative number to indicate some kind of error. | |
1392 | * | |
1393 | * Note that using this function requires that the client's adapter support | |
1394 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
1395 | * support this; its emulation through I2C messaging relies on a specific | |
1396 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
1397 | */ | |
b86a1bc8 JD |
1398 | s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command, |
1399 | u8 *values) | |
1400 | { | |
1401 | union i2c_smbus_data data; | |
1402 | ||
1403 | if (i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1404 | I2C_SMBUS_READ, command, | |
1405 | I2C_SMBUS_BLOCK_DATA, &data)) | |
1406 | return -1; | |
1407 | ||
1408 | memcpy(values, &data.block[1], data.block[0]); | |
1409 | return data.block[0]; | |
1410 | } | |
1411 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
1412 | ||
1da177e4 | 1413 | s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1414 | u8 length, const u8 *values) |
1da177e4 LT |
1415 | { |
1416 | union i2c_smbus_data data; | |
7656032b | 1417 | |
1da177e4 LT |
1418 | if (length > I2C_SMBUS_BLOCK_MAX) |
1419 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 1420 | data.block[0] = length; |
7656032b | 1421 | memcpy(&data.block[1], values, length); |
1da177e4 LT |
1422 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
1423 | I2C_SMBUS_WRITE,command, | |
1424 | I2C_SMBUS_BLOCK_DATA,&data); | |
1425 | } | |
c0564606 | 1426 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
1427 | |
1428 | /* Returns the number of read bytes */ | |
4b2643d7 JD |
1429 | s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, |
1430 | u8 length, u8 *values) | |
1da177e4 LT |
1431 | { |
1432 | union i2c_smbus_data data; | |
7656032b | 1433 | |
4b2643d7 JD |
1434 | if (length > I2C_SMBUS_BLOCK_MAX) |
1435 | length = I2C_SMBUS_BLOCK_MAX; | |
1436 | data.block[0] = length; | |
1da177e4 LT |
1437 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
1438 | I2C_SMBUS_READ,command, | |
1439 | I2C_SMBUS_I2C_BLOCK_DATA,&data)) | |
1440 | return -1; | |
7656032b JD |
1441 | |
1442 | memcpy(values, &data.block[1], data.block[0]); | |
1443 | return data.block[0]; | |
1da177e4 | 1444 | } |
c0564606 | 1445 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 1446 | |
21bbd691 | 1447 | s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1448 | u8 length, const u8 *values) |
21bbd691 JD |
1449 | { |
1450 | union i2c_smbus_data data; | |
1451 | ||
1452 | if (length > I2C_SMBUS_BLOCK_MAX) | |
1453 | length = I2C_SMBUS_BLOCK_MAX; | |
1454 | data.block[0] = length; | |
1455 | memcpy(data.block + 1, values, length); | |
1456 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1457 | I2C_SMBUS_WRITE, command, | |
1458 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1459 | } | |
c0564606 | 1460 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 1461 | |
438d6c2c | 1462 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 1463 | No checking of parameters is done! */ |
438d6c2c | 1464 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, |
1da177e4 | 1465 | unsigned short flags, |
438d6c2c | 1466 | char read_write, u8 command, int size, |
1da177e4 LT |
1467 | union i2c_smbus_data * data) |
1468 | { | |
1469 | /* So we need to generate a series of msgs. In the case of writing, we | |
1470 | need to use only one message; when reading, we need two. We initialize | |
1471 | most things with sane defaults, to keep the code below somewhat | |
1472 | simpler. */ | |
5c50d188 HI |
1473 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
1474 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
1da177e4 | 1475 | int num = read_write == I2C_SMBUS_READ?2:1; |
438d6c2c | 1476 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
1da177e4 LT |
1477 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
1478 | }; | |
1479 | int i; | |
421ef47b | 1480 | u8 partial_pec = 0; |
1da177e4 LT |
1481 | |
1482 | msgbuf0[0] = command; | |
1483 | switch(size) { | |
1484 | case I2C_SMBUS_QUICK: | |
1485 | msg[0].len = 0; | |
1486 | /* Special case: The read/write field is used as data */ | |
1487 | msg[0].flags = flags | (read_write==I2C_SMBUS_READ)?I2C_M_RD:0; | |
1488 | num = 1; | |
1489 | break; | |
1490 | case I2C_SMBUS_BYTE: | |
1491 | if (read_write == I2C_SMBUS_READ) { | |
1492 | /* Special case: only a read! */ | |
1493 | msg[0].flags = I2C_M_RD | flags; | |
1494 | num = 1; | |
1495 | } | |
1496 | break; | |
1497 | case I2C_SMBUS_BYTE_DATA: | |
1498 | if (read_write == I2C_SMBUS_READ) | |
1499 | msg[1].len = 1; | |
1500 | else { | |
1501 | msg[0].len = 2; | |
1502 | msgbuf0[1] = data->byte; | |
1503 | } | |
1504 | break; | |
1505 | case I2C_SMBUS_WORD_DATA: | |
1506 | if (read_write == I2C_SMBUS_READ) | |
1507 | msg[1].len = 2; | |
1508 | else { | |
1509 | msg[0].len=3; | |
1510 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1511 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1512 | } |
1513 | break; | |
1514 | case I2C_SMBUS_PROC_CALL: | |
1515 | num = 2; /* Special case */ | |
1516 | read_write = I2C_SMBUS_READ; | |
1517 | msg[0].len = 3; | |
1518 | msg[1].len = 2; | |
1519 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1520 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1521 | break; |
1522 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 1523 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
1524 | msg[1].flags |= I2C_M_RECV_LEN; |
1525 | msg[1].len = 1; /* block length will be added by | |
1526 | the underlying bus driver */ | |
1da177e4 LT |
1527 | } else { |
1528 | msg[0].len = data->block[0] + 2; | |
1529 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
1530 | dev_err(&adapter->dev, "smbus_access called with " | |
1531 | "invalid block write size (%d)\n", | |
1532 | data->block[0]); | |
1533 | return -1; | |
1534 | } | |
5c50d188 | 1535 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
1536 | msgbuf0[i] = data->block[i-1]; |
1537 | } | |
1538 | break; | |
1539 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
1540 | num = 2; /* Another special case */ |
1541 | read_write = I2C_SMBUS_READ; | |
1542 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
1543 | dev_err(&adapter->dev, "%s called with invalid " | |
08882d20 | 1544 | "block proc call size (%d)\n", __func__, |
209d27c3 JD |
1545 | data->block[0]); |
1546 | return -1; | |
1547 | } | |
1548 | msg[0].len = data->block[0] + 2; | |
1549 | for (i = 1; i < msg[0].len; i++) | |
1550 | msgbuf0[i] = data->block[i-1]; | |
1551 | msg[1].flags |= I2C_M_RECV_LEN; | |
1552 | msg[1].len = 1; /* block length will be added by | |
1553 | the underlying bus driver */ | |
1554 | break; | |
1da177e4 LT |
1555 | case I2C_SMBUS_I2C_BLOCK_DATA: |
1556 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 1557 | msg[1].len = data->block[0]; |
1da177e4 LT |
1558 | } else { |
1559 | msg[0].len = data->block[0] + 1; | |
30dac746 | 1560 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
1da177e4 LT |
1561 | dev_err(&adapter->dev, "i2c_smbus_xfer_emulated called with " |
1562 | "invalid block write size (%d)\n", | |
1563 | data->block[0]); | |
1564 | return -1; | |
1565 | } | |
1566 | for (i = 1; i <= data->block[0]; i++) | |
1567 | msgbuf0[i] = data->block[i]; | |
1568 | } | |
1569 | break; | |
1570 | default: | |
1571 | dev_err(&adapter->dev, "smbus_access called with invalid size (%d)\n", | |
1572 | size); | |
1573 | return -1; | |
1574 | } | |
1575 | ||
421ef47b JD |
1576 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
1577 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
1578 | if (i) { | |
1579 | /* Compute PEC if first message is a write */ | |
1580 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 1581 | if (num == 1) /* Write only */ |
421ef47b JD |
1582 | i2c_smbus_add_pec(&msg[0]); |
1583 | else /* Write followed by read */ | |
1584 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
1585 | } | |
1586 | /* Ask for PEC if last message is a read */ | |
1587 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 1588 | msg[num-1].len++; |
421ef47b JD |
1589 | } |
1590 | ||
1da177e4 LT |
1591 | if (i2c_transfer(adapter, msg, num) < 0) |
1592 | return -1; | |
1593 | ||
421ef47b JD |
1594 | /* Check PEC if last message is a read */ |
1595 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
1596 | if (i2c_smbus_check_pec(partial_pec, &msg[num-1]) < 0) | |
1597 | return -1; | |
1598 | } | |
1599 | ||
1da177e4 LT |
1600 | if (read_write == I2C_SMBUS_READ) |
1601 | switch(size) { | |
1602 | case I2C_SMBUS_BYTE: | |
1603 | data->byte = msgbuf0[0]; | |
1604 | break; | |
1605 | case I2C_SMBUS_BYTE_DATA: | |
1606 | data->byte = msgbuf1[0]; | |
1607 | break; | |
438d6c2c | 1608 | case I2C_SMBUS_WORD_DATA: |
1da177e4 LT |
1609 | case I2C_SMBUS_PROC_CALL: |
1610 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
1611 | break; | |
1612 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
4b2643d7 | 1613 | for (i = 0; i < data->block[0]; i++) |
1da177e4 LT |
1614 | data->block[i+1] = msgbuf1[i]; |
1615 | break; | |
209d27c3 JD |
1616 | case I2C_SMBUS_BLOCK_DATA: |
1617 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
1618 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
1619 | data->block[i] = msgbuf1[i]; | |
1620 | break; | |
1da177e4 LT |
1621 | } |
1622 | return 0; | |
1623 | } | |
1624 | ||
1625 | ||
1626 | s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags, | |
438d6c2c | 1627 | char read_write, u8 command, int size, |
1da177e4 LT |
1628 | union i2c_smbus_data * data) |
1629 | { | |
1630 | s32 res; | |
1da177e4 LT |
1631 | |
1632 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; | |
1da177e4 LT |
1633 | |
1634 | if (adapter->algo->smbus_xfer) { | |
5c085d36 | 1635 | mutex_lock(&adapter->bus_lock); |
1da177e4 LT |
1636 | res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write, |
1637 | command,size,data); | |
5c085d36 | 1638 | mutex_unlock(&adapter->bus_lock); |
1da177e4 LT |
1639 | } else |
1640 | res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write, | |
1641 | command,size,data); | |
1642 | ||
1da177e4 LT |
1643 | return res; |
1644 | } | |
1da177e4 | 1645 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
1646 | |
1647 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
1648 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
1649 | MODULE_LICENSE("GPL"); |