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> |
1da177e4 LT |
36 | #include <asm/uaccess.h> |
37 | ||
9c1600ed DB |
38 | #include "i2c-core.h" |
39 | ||
1da177e4 LT |
40 | |
41 | static LIST_HEAD(adapters); | |
42 | static LIST_HEAD(drivers); | |
b3585e4f | 43 | static DEFINE_MUTEX(core_lists); |
1da177e4 LT |
44 | static DEFINE_IDR(i2c_adapter_idr); |
45 | ||
a1d9e6e4 | 46 | #define is_newstyle_driver(d) ((d)->probe || (d)->remove) |
f37dd80a DB |
47 | |
48 | /* ------------------------------------------------------------------------- */ | |
49 | ||
1da177e4 LT |
50 | static int i2c_device_match(struct device *dev, struct device_driver *drv) |
51 | { | |
7b4fbc50 DB |
52 | struct i2c_client *client = to_i2c_client(dev); |
53 | struct i2c_driver *driver = to_i2c_driver(drv); | |
54 | ||
55 | /* make legacy i2c drivers bypass driver model probing entirely; | |
56 | * such drivers scan each i2c adapter/bus themselves. | |
57 | */ | |
a1d9e6e4 | 58 | if (!is_newstyle_driver(driver)) |
7b4fbc50 DB |
59 | return 0; |
60 | ||
61 | /* new style drivers use the same kind of driver matching policy | |
62 | * as platform devices or SPI: compare device and driver IDs. | |
63 | */ | |
64 | return strcmp(client->driver_name, drv->name) == 0; | |
1da177e4 LT |
65 | } |
66 | ||
7b4fbc50 DB |
67 | #ifdef CONFIG_HOTPLUG |
68 | ||
69 | /* uevent helps with hotplug: modprobe -q $(MODALIAS) */ | |
7eff2e7a | 70 | static int i2c_device_uevent(struct device *dev, struct kobj_uevent_env *env) |
7b4fbc50 DB |
71 | { |
72 | struct i2c_client *client = to_i2c_client(dev); | |
7b4fbc50 DB |
73 | |
74 | /* by definition, legacy drivers can't hotplug */ | |
75 | if (dev->driver || !client->driver_name) | |
76 | return 0; | |
77 | ||
7eff2e7a | 78 | if (add_uevent_var(env, "MODALIAS=%s", client->driver_name)) |
7b4fbc50 | 79 | return -ENOMEM; |
7b4fbc50 DB |
80 | dev_dbg(dev, "uevent\n"); |
81 | return 0; | |
82 | } | |
83 | ||
84 | #else | |
85 | #define i2c_device_uevent NULL | |
86 | #endif /* CONFIG_HOTPLUG */ | |
87 | ||
f37dd80a | 88 | static int i2c_device_probe(struct device *dev) |
1da177e4 | 89 | { |
7b4fbc50 DB |
90 | struct i2c_client *client = to_i2c_client(dev); |
91 | struct i2c_driver *driver = to_i2c_driver(dev->driver); | |
92 | ||
93 | if (!driver->probe) | |
94 | return -ENODEV; | |
95 | client->driver = driver; | |
96 | dev_dbg(dev, "probe\n"); | |
97 | return driver->probe(client); | |
f37dd80a | 98 | } |
1da177e4 | 99 | |
f37dd80a DB |
100 | static int i2c_device_remove(struct device *dev) |
101 | { | |
a1d9e6e4 DB |
102 | struct i2c_client *client = to_i2c_client(dev); |
103 | struct i2c_driver *driver; | |
104 | int status; | |
105 | ||
106 | if (!dev->driver) | |
107 | return 0; | |
108 | ||
109 | driver = to_i2c_driver(dev->driver); | |
110 | if (driver->remove) { | |
111 | dev_dbg(dev, "remove\n"); | |
112 | status = driver->remove(client); | |
113 | } else { | |
114 | dev->driver = NULL; | |
115 | status = 0; | |
116 | } | |
117 | if (status == 0) | |
118 | client->driver = NULL; | |
119 | return status; | |
1da177e4 LT |
120 | } |
121 | ||
f37dd80a | 122 | static void i2c_device_shutdown(struct device *dev) |
1da177e4 | 123 | { |
f37dd80a DB |
124 | struct i2c_driver *driver; |
125 | ||
126 | if (!dev->driver) | |
127 | return; | |
128 | driver = to_i2c_driver(dev->driver); | |
129 | if (driver->shutdown) | |
130 | driver->shutdown(to_i2c_client(dev)); | |
1da177e4 LT |
131 | } |
132 | ||
f37dd80a | 133 | static int i2c_device_suspend(struct device * dev, pm_message_t mesg) |
1da177e4 | 134 | { |
f37dd80a DB |
135 | struct i2c_driver *driver; |
136 | ||
137 | if (!dev->driver) | |
138 | return 0; | |
139 | driver = to_i2c_driver(dev->driver); | |
140 | if (!driver->suspend) | |
141 | return 0; | |
142 | return driver->suspend(to_i2c_client(dev), mesg); | |
1da177e4 LT |
143 | } |
144 | ||
f37dd80a | 145 | static int i2c_device_resume(struct device * dev) |
1da177e4 | 146 | { |
f37dd80a DB |
147 | struct i2c_driver *driver; |
148 | ||
149 | if (!dev->driver) | |
150 | return 0; | |
151 | driver = to_i2c_driver(dev->driver); | |
152 | if (!driver->resume) | |
153 | return 0; | |
154 | return driver->resume(to_i2c_client(dev)); | |
1da177e4 LT |
155 | } |
156 | ||
7b4fbc50 DB |
157 | static void i2c_client_release(struct device *dev) |
158 | { | |
159 | struct i2c_client *client = to_i2c_client(dev); | |
160 | complete(&client->released); | |
161 | } | |
162 | ||
9c1600ed DB |
163 | static void i2c_client_dev_release(struct device *dev) |
164 | { | |
165 | kfree(to_i2c_client(dev)); | |
166 | } | |
167 | ||
7b4fbc50 DB |
168 | static ssize_t show_client_name(struct device *dev, struct device_attribute *attr, char *buf) |
169 | { | |
170 | struct i2c_client *client = to_i2c_client(dev); | |
171 | return sprintf(buf, "%s\n", client->name); | |
172 | } | |
173 | ||
174 | static ssize_t show_modalias(struct device *dev, struct device_attribute *attr, char *buf) | |
175 | { | |
176 | struct i2c_client *client = to_i2c_client(dev); | |
177 | return client->driver_name | |
178 | ? sprintf(buf, "%s\n", client->driver_name) | |
179 | : 0; | |
180 | } | |
181 | ||
182 | static struct device_attribute i2c_dev_attrs[] = { | |
183 | __ATTR(name, S_IRUGO, show_client_name, NULL), | |
184 | /* modalias helps coldplug: modprobe $(cat .../modalias) */ | |
185 | __ATTR(modalias, S_IRUGO, show_modalias, NULL), | |
186 | { }, | |
187 | }; | |
188 | ||
83eaaed0 | 189 | static struct bus_type i2c_bus_type = { |
f37dd80a | 190 | .name = "i2c", |
7b4fbc50 | 191 | .dev_attrs = i2c_dev_attrs, |
f37dd80a | 192 | .match = i2c_device_match, |
7b4fbc50 | 193 | .uevent = i2c_device_uevent, |
f37dd80a DB |
194 | .probe = i2c_device_probe, |
195 | .remove = i2c_device_remove, | |
196 | .shutdown = i2c_device_shutdown, | |
197 | .suspend = i2c_device_suspend, | |
198 | .resume = i2c_device_resume, | |
b864c7d5 RK |
199 | }; |
200 | ||
9c1600ed DB |
201 | /** |
202 | * i2c_new_device - instantiate an i2c device for use with a new style driver | |
203 | * @adap: the adapter managing the device | |
204 | * @info: describes one I2C device; bus_num is ignored | |
d64f73be | 205 | * Context: can sleep |
9c1600ed DB |
206 | * |
207 | * Create a device to work with a new style i2c driver, where binding is | |
208 | * handled through driver model probe()/remove() methods. This call is not | |
209 | * appropriate for use by mainboad initialization logic, which usually runs | |
210 | * during an arch_initcall() long before any i2c_adapter could exist. | |
211 | * | |
212 | * This returns the new i2c client, which may be saved for later use with | |
213 | * i2c_unregister_device(); or NULL to indicate an error. | |
214 | */ | |
215 | struct i2c_client * | |
216 | i2c_new_device(struct i2c_adapter *adap, struct i2c_board_info const *info) | |
217 | { | |
218 | struct i2c_client *client; | |
219 | int status; | |
220 | ||
221 | client = kzalloc(sizeof *client, GFP_KERNEL); | |
222 | if (!client) | |
223 | return NULL; | |
224 | ||
225 | client->adapter = adap; | |
226 | ||
227 | client->dev.platform_data = info->platform_data; | |
3bbb835d DB |
228 | device_init_wakeup(&client->dev, info->flags & I2C_CLIENT_WAKE); |
229 | ||
230 | client->flags = info->flags & ~I2C_CLIENT_WAKE; | |
9c1600ed DB |
231 | client->addr = info->addr; |
232 | client->irq = info->irq; | |
233 | ||
234 | strlcpy(client->driver_name, info->driver_name, | |
235 | sizeof(client->driver_name)); | |
236 | strlcpy(client->name, info->type, sizeof(client->name)); | |
237 | ||
238 | /* a new style driver may be bound to this device when we | |
239 | * return from this function, or any later moment (e.g. maybe | |
240 | * hotplugging will load the driver module). and the device | |
241 | * refcount model is the standard driver model one. | |
242 | */ | |
243 | status = i2c_attach_client(client); | |
244 | if (status < 0) { | |
245 | kfree(client); | |
246 | client = NULL; | |
247 | } | |
248 | return client; | |
249 | } | |
250 | EXPORT_SYMBOL_GPL(i2c_new_device); | |
251 | ||
252 | ||
253 | /** | |
254 | * i2c_unregister_device - reverse effect of i2c_new_device() | |
255 | * @client: value returned from i2c_new_device() | |
d64f73be | 256 | * Context: can sleep |
9c1600ed DB |
257 | */ |
258 | void i2c_unregister_device(struct i2c_client *client) | |
a1d9e6e4 DB |
259 | { |
260 | struct i2c_adapter *adapter = client->adapter; | |
261 | struct i2c_driver *driver = client->driver; | |
262 | ||
263 | if (driver && !is_newstyle_driver(driver)) { | |
264 | dev_err(&client->dev, "can't unregister devices " | |
265 | "with legacy drivers\n"); | |
266 | WARN_ON(1); | |
267 | return; | |
268 | } | |
269 | ||
270 | mutex_lock(&adapter->clist_lock); | |
271 | list_del(&client->list); | |
272 | mutex_unlock(&adapter->clist_lock); | |
273 | ||
274 | device_unregister(&client->dev); | |
275 | } | |
9c1600ed | 276 | EXPORT_SYMBOL_GPL(i2c_unregister_device); |
a1d9e6e4 DB |
277 | |
278 | ||
f37dd80a DB |
279 | /* ------------------------------------------------------------------------- */ |
280 | ||
16ffadfc DB |
281 | /* I2C bus adapters -- one roots each I2C or SMBUS segment */ |
282 | ||
83eaaed0 | 283 | static void i2c_adapter_dev_release(struct device *dev) |
1da177e4 | 284 | { |
ef2c8321 | 285 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
1da177e4 LT |
286 | complete(&adap->dev_released); |
287 | } | |
288 | ||
16ffadfc DB |
289 | static ssize_t |
290 | show_adapter_name(struct device *dev, struct device_attribute *attr, char *buf) | |
291 | { | |
ef2c8321 | 292 | struct i2c_adapter *adap = to_i2c_adapter(dev); |
16ffadfc DB |
293 | return sprintf(buf, "%s\n", adap->name); |
294 | } | |
b119dc3f | 295 | |
16ffadfc DB |
296 | static struct device_attribute i2c_adapter_attrs[] = { |
297 | __ATTR(name, S_IRUGO, show_adapter_name, NULL), | |
298 | { }, | |
299 | }; | |
b119dc3f | 300 | |
83eaaed0 | 301 | static struct class i2c_adapter_class = { |
b119dc3f DB |
302 | .owner = THIS_MODULE, |
303 | .name = "i2c-adapter", | |
16ffadfc | 304 | .dev_attrs = i2c_adapter_attrs, |
1da177e4 LT |
305 | }; |
306 | ||
9c1600ed DB |
307 | static void i2c_scan_static_board_info(struct i2c_adapter *adapter) |
308 | { | |
309 | struct i2c_devinfo *devinfo; | |
310 | ||
311 | mutex_lock(&__i2c_board_lock); | |
312 | list_for_each_entry(devinfo, &__i2c_board_list, list) { | |
313 | if (devinfo->busnum == adapter->nr | |
314 | && !i2c_new_device(adapter, | |
315 | &devinfo->board_info)) | |
316 | printk(KERN_ERR "i2c-core: can't create i2c%d-%04x\n", | |
317 | i2c_adapter_id(adapter), | |
318 | devinfo->board_info.addr); | |
319 | } | |
320 | mutex_unlock(&__i2c_board_lock); | |
321 | } | |
322 | ||
6e13e641 | 323 | static int i2c_register_adapter(struct i2c_adapter *adap) |
1da177e4 | 324 | { |
6e13e641 | 325 | int res = 0; |
1da177e4 LT |
326 | struct list_head *item; |
327 | struct i2c_driver *driver; | |
328 | ||
5c085d36 IM |
329 | mutex_init(&adap->bus_lock); |
330 | mutex_init(&adap->clist_lock); | |
1da177e4 LT |
331 | INIT_LIST_HEAD(&adap->clients); |
332 | ||
6e13e641 DB |
333 | mutex_lock(&core_lists); |
334 | list_add_tail(&adap->list, &adapters); | |
335 | ||
1da177e4 LT |
336 | /* Add the adapter to the driver core. |
337 | * If the parent pointer is not set up, | |
338 | * we add this adapter to the host bus. | |
339 | */ | |
b119dc3f | 340 | if (adap->dev.parent == NULL) { |
1da177e4 | 341 | adap->dev.parent = &platform_bus; |
fe2c8d51 JD |
342 | pr_debug("I2C adapter driver [%s] forgot to specify " |
343 | "physical device\n", adap->name); | |
b119dc3f | 344 | } |
1da177e4 | 345 | sprintf(adap->dev.bus_id, "i2c-%d", adap->nr); |
1da177e4 | 346 | adap->dev.release = &i2c_adapter_dev_release; |
fccb56e4 | 347 | adap->dev.class = &i2c_adapter_class; |
b119c6c9 JD |
348 | res = device_register(&adap->dev); |
349 | if (res) | |
350 | goto out_list; | |
1da177e4 | 351 | |
b6d7b3d1 JD |
352 | dev_dbg(&adap->dev, "adapter [%s] registered\n", adap->name); |
353 | ||
6e13e641 DB |
354 | /* create pre-declared device nodes for new-style drivers */ |
355 | if (adap->nr < __i2c_first_dynamic_bus_num) | |
356 | i2c_scan_static_board_info(adap); | |
357 | ||
7b4fbc50 | 358 | /* let legacy drivers scan this bus for matching devices */ |
1da177e4 LT |
359 | list_for_each(item,&drivers) { |
360 | driver = list_entry(item, struct i2c_driver, list); | |
8a994755 | 361 | if (driver->attach_adapter) |
1da177e4 LT |
362 | /* We ignore the return code; if it fails, too bad */ |
363 | driver->attach_adapter(adap); | |
364 | } | |
365 | ||
1da177e4 | 366 | out_unlock: |
b3585e4f | 367 | mutex_unlock(&core_lists); |
1da177e4 | 368 | return res; |
b119c6c9 | 369 | |
b119c6c9 JD |
370 | out_list: |
371 | list_del(&adap->list); | |
372 | idr_remove(&i2c_adapter_idr, adap->nr); | |
373 | goto out_unlock; | |
1da177e4 LT |
374 | } |
375 | ||
6e13e641 DB |
376 | /** |
377 | * i2c_add_adapter - declare i2c adapter, use dynamic bus number | |
378 | * @adapter: the adapter to add | |
d64f73be | 379 | * Context: can sleep |
6e13e641 DB |
380 | * |
381 | * This routine is used to declare an I2C adapter when its bus number | |
382 | * doesn't matter. Examples: for I2C adapters dynamically added by | |
383 | * USB links or PCI plugin cards. | |
384 | * | |
385 | * When this returns zero, a new bus number was allocated and stored | |
386 | * in adap->nr, and the specified adapter became available for clients. | |
387 | * Otherwise, a negative errno value is returned. | |
388 | */ | |
389 | int i2c_add_adapter(struct i2c_adapter *adapter) | |
390 | { | |
391 | int id, res = 0; | |
392 | ||
393 | retry: | |
394 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
395 | return -ENOMEM; | |
396 | ||
397 | mutex_lock(&core_lists); | |
398 | /* "above" here means "above or equal to", sigh */ | |
399 | res = idr_get_new_above(&i2c_adapter_idr, adapter, | |
400 | __i2c_first_dynamic_bus_num, &id); | |
401 | mutex_unlock(&core_lists); | |
402 | ||
403 | if (res < 0) { | |
404 | if (res == -EAGAIN) | |
405 | goto retry; | |
406 | return res; | |
407 | } | |
408 | ||
409 | adapter->nr = id; | |
410 | return i2c_register_adapter(adapter); | |
411 | } | |
412 | EXPORT_SYMBOL(i2c_add_adapter); | |
413 | ||
414 | /** | |
415 | * i2c_add_numbered_adapter - declare i2c adapter, use static bus number | |
416 | * @adap: the adapter to register (with adap->nr initialized) | |
d64f73be | 417 | * Context: can sleep |
6e13e641 DB |
418 | * |
419 | * This routine is used to declare an I2C adapter when its bus number | |
420 | * matters. Example: for I2C adapters from system-on-chip CPUs, or | |
421 | * otherwise built in to the system's mainboard, and where i2c_board_info | |
422 | * is used to properly configure I2C devices. | |
423 | * | |
424 | * If no devices have pre-been declared for this bus, then be sure to | |
425 | * register the adapter before any dynamically allocated ones. Otherwise | |
426 | * the required bus ID may not be available. | |
427 | * | |
428 | * When this returns zero, the specified adapter became available for | |
429 | * clients using the bus number provided in adap->nr. Also, the table | |
430 | * of I2C devices pre-declared using i2c_register_board_info() is scanned, | |
431 | * and the appropriate driver model device nodes are created. Otherwise, a | |
432 | * negative errno value is returned. | |
433 | */ | |
434 | int i2c_add_numbered_adapter(struct i2c_adapter *adap) | |
435 | { | |
436 | int id; | |
437 | int status; | |
438 | ||
439 | if (adap->nr & ~MAX_ID_MASK) | |
440 | return -EINVAL; | |
441 | ||
442 | retry: | |
443 | if (idr_pre_get(&i2c_adapter_idr, GFP_KERNEL) == 0) | |
444 | return -ENOMEM; | |
445 | ||
446 | mutex_lock(&core_lists); | |
447 | /* "above" here means "above or equal to", sigh; | |
448 | * we need the "equal to" result to force the result | |
449 | */ | |
450 | status = idr_get_new_above(&i2c_adapter_idr, adap, adap->nr, &id); | |
451 | if (status == 0 && id != adap->nr) { | |
452 | status = -EBUSY; | |
453 | idr_remove(&i2c_adapter_idr, id); | |
454 | } | |
455 | mutex_unlock(&core_lists); | |
456 | if (status == -EAGAIN) | |
457 | goto retry; | |
458 | ||
459 | if (status == 0) | |
460 | status = i2c_register_adapter(adap); | |
461 | return status; | |
462 | } | |
463 | EXPORT_SYMBOL_GPL(i2c_add_numbered_adapter); | |
464 | ||
d64f73be DB |
465 | /** |
466 | * i2c_del_adapter - unregister I2C adapter | |
467 | * @adap: the adapter being unregistered | |
468 | * Context: can sleep | |
469 | * | |
470 | * This unregisters an I2C adapter which was previously registered | |
471 | * by @i2c_add_adapter or @i2c_add_numbered_adapter. | |
472 | */ | |
1da177e4 LT |
473 | int i2c_del_adapter(struct i2c_adapter *adap) |
474 | { | |
475 | struct list_head *item, *_n; | |
476 | struct i2c_adapter *adap_from_list; | |
477 | struct i2c_driver *driver; | |
478 | struct i2c_client *client; | |
479 | int res = 0; | |
480 | ||
b3585e4f | 481 | mutex_lock(&core_lists); |
1da177e4 LT |
482 | |
483 | /* First make sure that this adapter was ever added */ | |
484 | list_for_each_entry(adap_from_list, &adapters, list) { | |
485 | if (adap_from_list == adap) | |
486 | break; | |
487 | } | |
488 | if (adap_from_list != adap) { | |
b6d7b3d1 JD |
489 | pr_debug("i2c-core: attempting to delete unregistered " |
490 | "adapter [%s]\n", adap->name); | |
1da177e4 LT |
491 | res = -EINVAL; |
492 | goto out_unlock; | |
493 | } | |
494 | ||
495 | list_for_each(item,&drivers) { | |
496 | driver = list_entry(item, struct i2c_driver, list); | |
497 | if (driver->detach_adapter) | |
498 | if ((res = driver->detach_adapter(adap))) { | |
b6d7b3d1 | 499 | dev_err(&adap->dev, "detach_adapter failed " |
35d8b2e6 LR |
500 | "for driver [%s]\n", |
501 | driver->driver.name); | |
1da177e4 LT |
502 | goto out_unlock; |
503 | } | |
504 | } | |
505 | ||
506 | /* detach any active clients. This must be done first, because | |
a551acc2 | 507 | * it can fail; in which case we give up. */ |
1da177e4 | 508 | list_for_each_safe(item, _n, &adap->clients) { |
a1d9e6e4 DB |
509 | struct i2c_driver *driver; |
510 | ||
1da177e4 | 511 | client = list_entry(item, struct i2c_client, list); |
a1d9e6e4 DB |
512 | driver = client->driver; |
513 | ||
514 | /* new style, follow standard driver model */ | |
515 | if (!driver || is_newstyle_driver(driver)) { | |
516 | i2c_unregister_device(client); | |
517 | continue; | |
518 | } | |
1da177e4 | 519 | |
a1d9e6e4 DB |
520 | /* legacy drivers create and remove clients themselves */ |
521 | if ((res = driver->detach_client(client))) { | |
b6d7b3d1 JD |
522 | dev_err(&adap->dev, "detach_client failed for client " |
523 | "[%s] at address 0x%02x\n", client->name, | |
1da177e4 LT |
524 | client->addr); |
525 | goto out_unlock; | |
526 | } | |
527 | } | |
528 | ||
529 | /* clean up the sysfs representation */ | |
530 | init_completion(&adap->dev_released); | |
1da177e4 LT |
531 | device_unregister(&adap->dev); |
532 | list_del(&adap->list); | |
533 | ||
534 | /* wait for sysfs to drop all references */ | |
535 | wait_for_completion(&adap->dev_released); | |
1da177e4 | 536 | |
6e13e641 | 537 | /* free bus id */ |
1da177e4 LT |
538 | idr_remove(&i2c_adapter_idr, adap->nr); |
539 | ||
b6d7b3d1 | 540 | dev_dbg(&adap->dev, "adapter [%s] unregistered\n", adap->name); |
1da177e4 LT |
541 | |
542 | out_unlock: | |
b3585e4f | 543 | mutex_unlock(&core_lists); |
1da177e4 LT |
544 | return res; |
545 | } | |
c0564606 | 546 | EXPORT_SYMBOL(i2c_del_adapter); |
1da177e4 LT |
547 | |
548 | ||
7b4fbc50 DB |
549 | /* ------------------------------------------------------------------------- */ |
550 | ||
551 | /* | |
552 | * An i2c_driver is used with one or more i2c_client (device) nodes to access | |
553 | * i2c slave chips, on a bus instance associated with some i2c_adapter. There | |
554 | * are two models for binding the driver to its device: "new style" drivers | |
555 | * follow the standard Linux driver model and just respond to probe() calls | |
556 | * issued if the driver core sees they match(); "legacy" drivers create device | |
557 | * nodes themselves. | |
1da177e4 LT |
558 | */ |
559 | ||
de59cf9e | 560 | int i2c_register_driver(struct module *owner, struct i2c_driver *driver) |
1da177e4 | 561 | { |
7eebcb7c | 562 | int res; |
1da177e4 | 563 | |
7b4fbc50 | 564 | /* new style driver methods can't mix with legacy ones */ |
a1d9e6e4 | 565 | if (is_newstyle_driver(driver)) { |
7b4fbc50 DB |
566 | if (driver->attach_adapter || driver->detach_adapter |
567 | || driver->detach_client) { | |
568 | printk(KERN_WARNING | |
569 | "i2c-core: driver [%s] is confused\n", | |
570 | driver->driver.name); | |
571 | return -EINVAL; | |
572 | } | |
573 | } | |
574 | ||
1da177e4 | 575 | /* add the driver to the list of i2c drivers in the driver core */ |
de59cf9e | 576 | driver->driver.owner = owner; |
1da177e4 | 577 | driver->driver.bus = &i2c_bus_type; |
1da177e4 | 578 | |
6e13e641 DB |
579 | /* for new style drivers, when registration returns the driver core |
580 | * will have called probe() for all matching-but-unbound devices. | |
581 | */ | |
1da177e4 LT |
582 | res = driver_register(&driver->driver); |
583 | if (res) | |
7eebcb7c | 584 | return res; |
438d6c2c | 585 | |
7eebcb7c JD |
586 | mutex_lock(&core_lists); |
587 | ||
1da177e4 | 588 | list_add_tail(&driver->list,&drivers); |
35d8b2e6 | 589 | pr_debug("i2c-core: driver [%s] registered\n", driver->driver.name); |
1da177e4 | 590 | |
7b4fbc50 | 591 | /* legacy drivers scan i2c busses directly */ |
8a994755 | 592 | if (driver->attach_adapter) { |
4ad4eac6 DB |
593 | struct i2c_adapter *adapter; |
594 | ||
595 | list_for_each_entry(adapter, &adapters, list) { | |
1da177e4 LT |
596 | driver->attach_adapter(adapter); |
597 | } | |
598 | } | |
599 | ||
b3585e4f | 600 | mutex_unlock(&core_lists); |
7eebcb7c | 601 | return 0; |
1da177e4 | 602 | } |
de59cf9e | 603 | EXPORT_SYMBOL(i2c_register_driver); |
1da177e4 | 604 | |
a1d9e6e4 DB |
605 | /** |
606 | * i2c_del_driver - unregister I2C driver | |
607 | * @driver: the driver being unregistered | |
d64f73be | 608 | * Context: can sleep |
a1d9e6e4 | 609 | */ |
b3e82096 | 610 | void i2c_del_driver(struct i2c_driver *driver) |
1da177e4 LT |
611 | { |
612 | struct list_head *item1, *item2, *_n; | |
613 | struct i2c_client *client; | |
614 | struct i2c_adapter *adap; | |
438d6c2c | 615 | |
b3585e4f | 616 | mutex_lock(&core_lists); |
1da177e4 | 617 | |
a1d9e6e4 DB |
618 | /* new-style driver? */ |
619 | if (is_newstyle_driver(driver)) | |
620 | goto unregister; | |
621 | ||
1da177e4 | 622 | /* Have a look at each adapter, if clients of this driver are still |
438d6c2c | 623 | * attached. If so, detach them to be able to kill the driver |
1da177e4 | 624 | * afterwards. |
1da177e4 LT |
625 | */ |
626 | list_for_each(item1,&adapters) { | |
627 | adap = list_entry(item1, struct i2c_adapter, list); | |
1da177e4 | 628 | if (driver->detach_adapter) { |
b3e82096 | 629 | if (driver->detach_adapter(adap)) { |
b6d7b3d1 | 630 | dev_err(&adap->dev, "detach_adapter failed " |
35d8b2e6 LR |
631 | "for driver [%s]\n", |
632 | driver->driver.name); | |
1da177e4 LT |
633 | } |
634 | } else { | |
635 | list_for_each_safe(item2, _n, &adap->clients) { | |
636 | client = list_entry(item2, struct i2c_client, list); | |
637 | if (client->driver != driver) | |
638 | continue; | |
b6d7b3d1 JD |
639 | dev_dbg(&adap->dev, "detaching client [%s] " |
640 | "at 0x%02x\n", client->name, | |
641 | client->addr); | |
b3e82096 | 642 | if (driver->detach_client(client)) { |
b6d7b3d1 JD |
643 | dev_err(&adap->dev, "detach_client " |
644 | "failed for client [%s] at " | |
645 | "0x%02x\n", client->name, | |
1da177e4 | 646 | client->addr); |
1da177e4 LT |
647 | } |
648 | } | |
649 | } | |
650 | } | |
651 | ||
a1d9e6e4 | 652 | unregister: |
1da177e4 LT |
653 | driver_unregister(&driver->driver); |
654 | list_del(&driver->list); | |
35d8b2e6 | 655 | pr_debug("i2c-core: driver [%s] unregistered\n", driver->driver.name); |
1da177e4 | 656 | |
b3585e4f | 657 | mutex_unlock(&core_lists); |
1da177e4 | 658 | } |
c0564606 | 659 | EXPORT_SYMBOL(i2c_del_driver); |
1da177e4 | 660 | |
7b4fbc50 DB |
661 | /* ------------------------------------------------------------------------- */ |
662 | ||
1da177e4 LT |
663 | static int __i2c_check_addr(struct i2c_adapter *adapter, unsigned int addr) |
664 | { | |
665 | struct list_head *item; | |
666 | struct i2c_client *client; | |
667 | ||
668 | list_for_each(item,&adapter->clients) { | |
669 | client = list_entry(item, struct i2c_client, list); | |
670 | if (client->addr == addr) | |
671 | return -EBUSY; | |
672 | } | |
673 | return 0; | |
674 | } | |
675 | ||
5e31c2bd | 676 | static int i2c_check_addr(struct i2c_adapter *adapter, int addr) |
1da177e4 LT |
677 | { |
678 | int rval; | |
679 | ||
5c085d36 | 680 | mutex_lock(&adapter->clist_lock); |
1da177e4 | 681 | rval = __i2c_check_addr(adapter, addr); |
5c085d36 | 682 | mutex_unlock(&adapter->clist_lock); |
1da177e4 LT |
683 | |
684 | return rval; | |
685 | } | |
686 | ||
687 | int i2c_attach_client(struct i2c_client *client) | |
688 | { | |
689 | struct i2c_adapter *adapter = client->adapter; | |
b119c6c9 | 690 | int res = 0; |
1da177e4 | 691 | |
5c085d36 | 692 | mutex_lock(&adapter->clist_lock); |
1da177e4 | 693 | if (__i2c_check_addr(client->adapter, client->addr)) { |
b119c6c9 JD |
694 | res = -EBUSY; |
695 | goto out_unlock; | |
1da177e4 LT |
696 | } |
697 | list_add_tail(&client->list,&adapter->clients); | |
438d6c2c | 698 | |
1da177e4 | 699 | client->dev.parent = &client->adapter->dev; |
1da177e4 | 700 | client->dev.bus = &i2c_bus_type; |
9c1600ed DB |
701 | |
702 | if (client->driver) | |
703 | client->dev.driver = &client->driver->driver; | |
704 | ||
de81d2aa | 705 | if (client->driver && !is_newstyle_driver(client->driver)) { |
9c1600ed | 706 | client->dev.release = i2c_client_release; |
de81d2aa DB |
707 | client->dev.uevent_suppress = 1; |
708 | } else | |
9c1600ed | 709 | client->dev.release = i2c_client_dev_release; |
438d6c2c | 710 | |
1da177e4 LT |
711 | snprintf(&client->dev.bus_id[0], sizeof(client->dev.bus_id), |
712 | "%d-%04x", i2c_adapter_id(adapter), client->addr); | |
b6d7b3d1 JD |
713 | dev_dbg(&adapter->dev, "client [%s] registered with bus id %s\n", |
714 | client->name, client->dev.bus_id); | |
b119c6c9 JD |
715 | res = device_register(&client->dev); |
716 | if (res) | |
717 | goto out_list; | |
b119c6c9 | 718 | mutex_unlock(&adapter->clist_lock); |
77ed74da JD |
719 | |
720 | if (adapter->client_register) { | |
721 | if (adapter->client_register(client)) { | |
722 | dev_dbg(&adapter->dev, "client_register " | |
723 | "failed for client [%s] at 0x%02x\n", | |
724 | client->name, client->addr); | |
725 | } | |
726 | } | |
727 | ||
728 | return 0; | |
b119c6c9 | 729 | |
b119c6c9 JD |
730 | out_list: |
731 | list_del(&client->list); | |
732 | dev_err(&adapter->dev, "Failed to attach i2c client %s at 0x%02x " | |
733 | "(%d)\n", client->name, client->addr, res); | |
77ed74da JD |
734 | out_unlock: |
735 | mutex_unlock(&adapter->clist_lock); | |
736 | return res; | |
1da177e4 | 737 | } |
c0564606 | 738 | EXPORT_SYMBOL(i2c_attach_client); |
1da177e4 LT |
739 | |
740 | int i2c_detach_client(struct i2c_client *client) | |
741 | { | |
742 | struct i2c_adapter *adapter = client->adapter; | |
743 | int res = 0; | |
438d6c2c | 744 | |
1da177e4 LT |
745 | if (adapter->client_unregister) { |
746 | res = adapter->client_unregister(client); | |
747 | if (res) { | |
748 | dev_err(&client->dev, | |
86749e85 JD |
749 | "client_unregister [%s] failed, " |
750 | "client not detached\n", client->name); | |
1da177e4 LT |
751 | goto out; |
752 | } | |
753 | } | |
754 | ||
5c085d36 | 755 | mutex_lock(&adapter->clist_lock); |
1da177e4 LT |
756 | list_del(&client->list); |
757 | init_completion(&client->released); | |
1da177e4 | 758 | device_unregister(&client->dev); |
5c085d36 | 759 | mutex_unlock(&adapter->clist_lock); |
1da177e4 LT |
760 | wait_for_completion(&client->released); |
761 | ||
762 | out: | |
763 | return res; | |
764 | } | |
c0564606 | 765 | EXPORT_SYMBOL(i2c_detach_client); |
1da177e4 | 766 | |
1da177e4 LT |
767 | int i2c_use_client(struct i2c_client *client) |
768 | { | |
bdc511f4 | 769 | get_device(&client->dev); |
1da177e4 | 770 | return 0; |
1da177e4 | 771 | } |
c0564606 | 772 | EXPORT_SYMBOL(i2c_use_client); |
1da177e4 LT |
773 | |
774 | int i2c_release_client(struct i2c_client *client) | |
775 | { | |
bdc511f4 | 776 | put_device(&client->dev); |
1da177e4 LT |
777 | return 0; |
778 | } | |
c0564606 | 779 | EXPORT_SYMBOL(i2c_release_client); |
1da177e4 LT |
780 | |
781 | void i2c_clients_command(struct i2c_adapter *adap, unsigned int cmd, void *arg) | |
782 | { | |
783 | struct list_head *item; | |
784 | struct i2c_client *client; | |
785 | ||
5c085d36 | 786 | mutex_lock(&adap->clist_lock); |
1da177e4 LT |
787 | list_for_each(item,&adap->clients) { |
788 | client = list_entry(item, struct i2c_client, list); | |
35d8b2e6 | 789 | if (!try_module_get(client->driver->driver.owner)) |
1da177e4 LT |
790 | continue; |
791 | if (NULL != client->driver->command) { | |
5c085d36 | 792 | mutex_unlock(&adap->clist_lock); |
1da177e4 | 793 | client->driver->command(client,cmd,arg); |
5c085d36 | 794 | mutex_lock(&adap->clist_lock); |
1da177e4 | 795 | } |
35d8b2e6 | 796 | module_put(client->driver->driver.owner); |
1da177e4 | 797 | } |
5c085d36 | 798 | mutex_unlock(&adap->clist_lock); |
1da177e4 | 799 | } |
c0564606 | 800 | EXPORT_SYMBOL(i2c_clients_command); |
1da177e4 LT |
801 | |
802 | static int __init i2c_init(void) | |
803 | { | |
804 | int retval; | |
805 | ||
806 | retval = bus_register(&i2c_bus_type); | |
1da177e4 LT |
807 | if (retval) |
808 | return retval; | |
809 | return class_register(&i2c_adapter_class); | |
810 | } | |
811 | ||
812 | static void __exit i2c_exit(void) | |
813 | { | |
814 | class_unregister(&i2c_adapter_class); | |
1da177e4 LT |
815 | bus_unregister(&i2c_bus_type); |
816 | } | |
817 | ||
818 | subsys_initcall(i2c_init); | |
819 | module_exit(i2c_exit); | |
820 | ||
821 | /* ---------------------------------------------------- | |
822 | * the functional interface to the i2c busses. | |
823 | * ---------------------------------------------------- | |
824 | */ | |
825 | ||
826 | int i2c_transfer(struct i2c_adapter * adap, struct i2c_msg *msgs, int num) | |
827 | { | |
828 | int ret; | |
829 | ||
830 | if (adap->algo->master_xfer) { | |
831 | #ifdef DEBUG | |
832 | for (ret = 0; ret < num; ret++) { | |
833 | dev_dbg(&adap->dev, "master_xfer[%d] %c, addr=0x%02x, " | |
209d27c3 JD |
834 | "len=%d%s\n", ret, (msgs[ret].flags & I2C_M_RD) |
835 | ? 'R' : 'W', msgs[ret].addr, msgs[ret].len, | |
836 | (msgs[ret].flags & I2C_M_RECV_LEN) ? "+" : ""); | |
1da177e4 LT |
837 | } |
838 | #endif | |
839 | ||
6ea23039 | 840 | mutex_lock_nested(&adap->bus_lock, adap->level); |
1da177e4 | 841 | ret = adap->algo->master_xfer(adap,msgs,num); |
5c085d36 | 842 | mutex_unlock(&adap->bus_lock); |
1da177e4 LT |
843 | |
844 | return ret; | |
845 | } else { | |
846 | dev_dbg(&adap->dev, "I2C level transfers not supported\n"); | |
847 | return -ENOSYS; | |
848 | } | |
849 | } | |
c0564606 | 850 | EXPORT_SYMBOL(i2c_transfer); |
1da177e4 LT |
851 | |
852 | int i2c_master_send(struct i2c_client *client,const char *buf ,int count) | |
853 | { | |
854 | int ret; | |
855 | struct i2c_adapter *adap=client->adapter; | |
856 | struct i2c_msg msg; | |
857 | ||
815f55f2 JD |
858 | msg.addr = client->addr; |
859 | msg.flags = client->flags & I2C_M_TEN; | |
860 | msg.len = count; | |
861 | msg.buf = (char *)buf; | |
438d6c2c | 862 | |
815f55f2 | 863 | ret = i2c_transfer(adap, &msg, 1); |
1da177e4 | 864 | |
815f55f2 JD |
865 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes |
866 | transmitted, else error code. */ | |
867 | return (ret == 1) ? count : ret; | |
1da177e4 | 868 | } |
c0564606 | 869 | EXPORT_SYMBOL(i2c_master_send); |
1da177e4 LT |
870 | |
871 | int i2c_master_recv(struct i2c_client *client, char *buf ,int count) | |
872 | { | |
873 | struct i2c_adapter *adap=client->adapter; | |
874 | struct i2c_msg msg; | |
875 | int ret; | |
815f55f2 JD |
876 | |
877 | msg.addr = client->addr; | |
878 | msg.flags = client->flags & I2C_M_TEN; | |
879 | msg.flags |= I2C_M_RD; | |
880 | msg.len = count; | |
881 | msg.buf = buf; | |
882 | ||
883 | ret = i2c_transfer(adap, &msg, 1); | |
884 | ||
885 | /* If everything went ok (i.e. 1 msg transmitted), return #bytes | |
886 | transmitted, else error code. */ | |
887 | return (ret == 1) ? count : ret; | |
1da177e4 | 888 | } |
c0564606 | 889 | EXPORT_SYMBOL(i2c_master_recv); |
1da177e4 | 890 | |
1da177e4 LT |
891 | /* ---------------------------------------------------- |
892 | * the i2c address scanning function | |
893 | * Will not work for 10-bit addresses! | |
894 | * ---------------------------------------------------- | |
895 | */ | |
a89ba0bc JD |
896 | static int i2c_probe_address(struct i2c_adapter *adapter, int addr, int kind, |
897 | int (*found_proc) (struct i2c_adapter *, int, int)) | |
898 | { | |
899 | int err; | |
900 | ||
901 | /* Make sure the address is valid */ | |
902 | if (addr < 0x03 || addr > 0x77) { | |
903 | dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", | |
904 | addr); | |
905 | return -EINVAL; | |
9fc6adfa JD |
906 | } |
907 | ||
a89ba0bc JD |
908 | /* Skip if already in use */ |
909 | if (i2c_check_addr(adapter, addr)) | |
910 | return 0; | |
911 | ||
912 | /* Make sure there is something at this address, unless forced */ | |
4c9337da JD |
913 | if (kind < 0) { |
914 | if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, | |
915 | I2C_SMBUS_QUICK, NULL) < 0) | |
916 | return 0; | |
917 | ||
918 | /* prevent 24RF08 corruption */ | |
919 | if ((addr & ~0x0f) == 0x50) | |
920 | i2c_smbus_xfer(adapter, addr, 0, 0, 0, | |
921 | I2C_SMBUS_QUICK, NULL); | |
922 | } | |
a89ba0bc JD |
923 | |
924 | /* Finally call the custom detection function */ | |
925 | err = found_proc(adapter, addr, kind); | |
a89ba0bc JD |
926 | /* -ENODEV can be returned if there is a chip at the given address |
927 | but it isn't supported by this chip driver. We catch it here as | |
928 | this isn't an error. */ | |
114fd183 JD |
929 | if (err == -ENODEV) |
930 | err = 0; | |
931 | ||
932 | if (err) | |
933 | dev_warn(&adapter->dev, "Client creation failed at 0x%x (%d)\n", | |
934 | addr, err); | |
935 | return err; | |
9fc6adfa JD |
936 | } |
937 | ||
1da177e4 | 938 | int i2c_probe(struct i2c_adapter *adapter, |
bfb6df24 | 939 | const struct i2c_client_address_data *address_data, |
1da177e4 LT |
940 | int (*found_proc) (struct i2c_adapter *, int, int)) |
941 | { | |
a89ba0bc | 942 | int i, err; |
1da177e4 LT |
943 | int adap_id = i2c_adapter_id(adapter); |
944 | ||
a89ba0bc JD |
945 | /* Force entries are done first, and are not affected by ignore |
946 | entries */ | |
947 | if (address_data->forces) { | |
bfb6df24 | 948 | const unsigned short * const *forces = address_data->forces; |
a89ba0bc JD |
949 | int kind; |
950 | ||
951 | for (kind = 0; forces[kind]; kind++) { | |
952 | for (i = 0; forces[kind][i] != I2C_CLIENT_END; | |
953 | i += 2) { | |
954 | if (forces[kind][i] == adap_id | |
955 | || forces[kind][i] == ANY_I2C_BUS) { | |
956 | dev_dbg(&adapter->dev, "found force " | |
957 | "parameter for adapter %d, " | |
958 | "addr 0x%02x, kind %d\n", | |
959 | adap_id, forces[kind][i + 1], | |
960 | kind); | |
961 | err = i2c_probe_address(adapter, | |
962 | forces[kind][i + 1], | |
963 | kind, found_proc); | |
964 | if (err) | |
965 | return err; | |
966 | } | |
1da177e4 LT |
967 | } |
968 | } | |
a89ba0bc | 969 | } |
1da177e4 | 970 | |
4366dc94 JD |
971 | /* Stop here if we can't use SMBUS_QUICK */ |
972 | if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_QUICK)) { | |
973 | if (address_data->probe[0] == I2C_CLIENT_END | |
974 | && address_data->normal_i2c[0] == I2C_CLIENT_END) | |
438d6c2c | 975 | return 0; |
4366dc94 JD |
976 | |
977 | dev_warn(&adapter->dev, "SMBus Quick command not supported, " | |
978 | "can't probe for chips\n"); | |
979 | return -1; | |
980 | } | |
981 | ||
a89ba0bc JD |
982 | /* Probe entries are done second, and are not affected by ignore |
983 | entries either */ | |
984 | for (i = 0; address_data->probe[i] != I2C_CLIENT_END; i += 2) { | |
985 | if (address_data->probe[i] == adap_id | |
986 | || address_data->probe[i] == ANY_I2C_BUS) { | |
987 | dev_dbg(&adapter->dev, "found probe parameter for " | |
988 | "adapter %d, addr 0x%02x\n", adap_id, | |
989 | address_data->probe[i + 1]); | |
990 | err = i2c_probe_address(adapter, | |
991 | address_data->probe[i + 1], | |
992 | -1, found_proc); | |
993 | if (err) | |
994 | return err; | |
1da177e4 | 995 | } |
a89ba0bc | 996 | } |
1da177e4 | 997 | |
a89ba0bc JD |
998 | /* Normal entries are done last, unless shadowed by an ignore entry */ |
999 | for (i = 0; address_data->normal_i2c[i] != I2C_CLIENT_END; i += 1) { | |
1000 | int j, ignore; | |
1001 | ||
1002 | ignore = 0; | |
1003 | for (j = 0; address_data->ignore[j] != I2C_CLIENT_END; | |
1004 | j += 2) { | |
1005 | if ((address_data->ignore[j] == adap_id || | |
1006 | address_data->ignore[j] == ANY_I2C_BUS) | |
1007 | && address_data->ignore[j + 1] | |
1008 | == address_data->normal_i2c[i]) { | |
1009 | dev_dbg(&adapter->dev, "found ignore " | |
1010 | "parameter for adapter %d, " | |
1011 | "addr 0x%02x\n", adap_id, | |
1012 | address_data->ignore[j + 1]); | |
2369df93 MH |
1013 | ignore = 1; |
1014 | break; | |
1da177e4 LT |
1015 | } |
1016 | } | |
a89ba0bc | 1017 | if (ignore) |
1da177e4 LT |
1018 | continue; |
1019 | ||
a89ba0bc JD |
1020 | dev_dbg(&adapter->dev, "found normal entry for adapter %d, " |
1021 | "addr 0x%02x\n", adap_id, | |
1022 | address_data->normal_i2c[i]); | |
1023 | err = i2c_probe_address(adapter, address_data->normal_i2c[i], | |
1024 | -1, found_proc); | |
1025 | if (err) | |
1026 | return err; | |
1da177e4 | 1027 | } |
a89ba0bc | 1028 | |
1da177e4 LT |
1029 | return 0; |
1030 | } | |
c0564606 | 1031 | EXPORT_SYMBOL(i2c_probe); |
1da177e4 | 1032 | |
12b5053a JD |
1033 | struct i2c_client * |
1034 | i2c_new_probed_device(struct i2c_adapter *adap, | |
1035 | struct i2c_board_info *info, | |
1036 | unsigned short const *addr_list) | |
1037 | { | |
1038 | int i; | |
1039 | ||
1040 | /* Stop here if the bus doesn't support probing */ | |
1041 | if (!i2c_check_functionality(adap, I2C_FUNC_SMBUS_READ_BYTE)) { | |
1042 | dev_err(&adap->dev, "Probing not supported\n"); | |
1043 | return NULL; | |
1044 | } | |
1045 | ||
1046 | mutex_lock(&adap->clist_lock); | |
1047 | for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { | |
1048 | /* Check address validity */ | |
1049 | if (addr_list[i] < 0x03 || addr_list[i] > 0x77) { | |
1050 | dev_warn(&adap->dev, "Invalid 7-bit address " | |
1051 | "0x%02x\n", addr_list[i]); | |
1052 | continue; | |
1053 | } | |
1054 | ||
1055 | /* Check address availability */ | |
1056 | if (__i2c_check_addr(adap, addr_list[i])) { | |
1057 | dev_dbg(&adap->dev, "Address 0x%02x already in " | |
1058 | "use, not probing\n", addr_list[i]); | |
1059 | continue; | |
1060 | } | |
1061 | ||
1062 | /* Test address responsiveness | |
1063 | The default probe method is a quick write, but it is known | |
1064 | to corrupt the 24RF08 EEPROMs due to a state machine bug, | |
1065 | and could also irreversibly write-protect some EEPROMs, so | |
1066 | for address ranges 0x30-0x37 and 0x50-0x5f, we use a byte | |
1067 | read instead. Also, some bus drivers don't implement | |
1068 | quick write, so we fallback to a byte read it that case | |
1069 | too. */ | |
1070 | if ((addr_list[i] & ~0x07) == 0x30 | |
1071 | || (addr_list[i] & ~0x0f) == 0x50 | |
1072 | || !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) { | |
1073 | if (i2c_smbus_xfer(adap, addr_list[i], 0, | |
1074 | I2C_SMBUS_READ, 0, | |
1075 | I2C_SMBUS_BYTE, NULL) >= 0) | |
1076 | break; | |
1077 | } else { | |
1078 | if (i2c_smbus_xfer(adap, addr_list[i], 0, | |
1079 | I2C_SMBUS_WRITE, 0, | |
1080 | I2C_SMBUS_QUICK, NULL) >= 0) | |
1081 | break; | |
1082 | } | |
1083 | } | |
1084 | mutex_unlock(&adap->clist_lock); | |
1085 | ||
1086 | if (addr_list[i] == I2C_CLIENT_END) { | |
1087 | dev_dbg(&adap->dev, "Probing failed, no device found\n"); | |
1088 | return NULL; | |
1089 | } | |
1090 | ||
1091 | info->addr = addr_list[i]; | |
1092 | return i2c_new_device(adap, info); | |
1093 | } | |
1094 | EXPORT_SYMBOL_GPL(i2c_new_probed_device); | |
1095 | ||
1da177e4 LT |
1096 | struct i2c_adapter* i2c_get_adapter(int id) |
1097 | { | |
1da177e4 | 1098 | struct i2c_adapter *adapter; |
438d6c2c | 1099 | |
b3585e4f | 1100 | mutex_lock(&core_lists); |
a0920e10 MH |
1101 | adapter = (struct i2c_adapter *)idr_find(&i2c_adapter_idr, id); |
1102 | if (adapter && !try_module_get(adapter->owner)) | |
1103 | adapter = NULL; | |
1104 | ||
b3585e4f | 1105 | mutex_unlock(&core_lists); |
a0920e10 | 1106 | return adapter; |
1da177e4 | 1107 | } |
c0564606 | 1108 | EXPORT_SYMBOL(i2c_get_adapter); |
1da177e4 LT |
1109 | |
1110 | void i2c_put_adapter(struct i2c_adapter *adap) | |
1111 | { | |
1112 | module_put(adap->owner); | |
1113 | } | |
c0564606 | 1114 | EXPORT_SYMBOL(i2c_put_adapter); |
1da177e4 LT |
1115 | |
1116 | /* The SMBus parts */ | |
1117 | ||
438d6c2c | 1118 | #define POLY (0x1070U << 3) |
1da177e4 LT |
1119 | static u8 |
1120 | crc8(u16 data) | |
1121 | { | |
1122 | int i; | |
438d6c2c | 1123 | |
1da177e4 | 1124 | for(i = 0; i < 8; i++) { |
438d6c2c | 1125 | if (data & 0x8000) |
1da177e4 LT |
1126 | data = data ^ POLY; |
1127 | data = data << 1; | |
1128 | } | |
1129 | return (u8)(data >> 8); | |
1130 | } | |
1131 | ||
421ef47b JD |
1132 | /* Incremental CRC8 over count bytes in the array pointed to by p */ |
1133 | static u8 i2c_smbus_pec(u8 crc, u8 *p, size_t count) | |
1da177e4 LT |
1134 | { |
1135 | int i; | |
1136 | ||
1137 | for(i = 0; i < count; i++) | |
421ef47b | 1138 | crc = crc8((crc ^ p[i]) << 8); |
1da177e4 LT |
1139 | return crc; |
1140 | } | |
1141 | ||
421ef47b JD |
1142 | /* Assume a 7-bit address, which is reasonable for SMBus */ |
1143 | static u8 i2c_smbus_msg_pec(u8 pec, struct i2c_msg *msg) | |
1da177e4 | 1144 | { |
421ef47b JD |
1145 | /* The address will be sent first */ |
1146 | u8 addr = (msg->addr << 1) | !!(msg->flags & I2C_M_RD); | |
1147 | pec = i2c_smbus_pec(pec, &addr, 1); | |
1148 | ||
1149 | /* The data buffer follows */ | |
1150 | return i2c_smbus_pec(pec, msg->buf, msg->len); | |
1da177e4 LT |
1151 | } |
1152 | ||
421ef47b JD |
1153 | /* Used for write only transactions */ |
1154 | static inline void i2c_smbus_add_pec(struct i2c_msg *msg) | |
1da177e4 | 1155 | { |
421ef47b JD |
1156 | msg->buf[msg->len] = i2c_smbus_msg_pec(0, msg); |
1157 | msg->len++; | |
1da177e4 LT |
1158 | } |
1159 | ||
421ef47b JD |
1160 | /* Return <0 on CRC error |
1161 | If there was a write before this read (most cases) we need to take the | |
1162 | partial CRC from the write part into account. | |
1163 | Note that this function does modify the message (we need to decrease the | |
1164 | message length to hide the CRC byte from the caller). */ | |
1165 | static int i2c_smbus_check_pec(u8 cpec, struct i2c_msg *msg) | |
1da177e4 | 1166 | { |
421ef47b JD |
1167 | u8 rpec = msg->buf[--msg->len]; |
1168 | cpec = i2c_smbus_msg_pec(cpec, msg); | |
1da177e4 | 1169 | |
1da177e4 LT |
1170 | if (rpec != cpec) { |
1171 | pr_debug("i2c-core: Bad PEC 0x%02x vs. 0x%02x\n", | |
1172 | rpec, cpec); | |
1173 | return -1; | |
1174 | } | |
438d6c2c | 1175 | return 0; |
1da177e4 LT |
1176 | } |
1177 | ||
1178 | s32 i2c_smbus_write_quick(struct i2c_client *client, u8 value) | |
1179 | { | |
1180 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
438d6c2c | 1181 | value,0,I2C_SMBUS_QUICK,NULL); |
1da177e4 | 1182 | } |
c0564606 | 1183 | EXPORT_SYMBOL(i2c_smbus_write_quick); |
1da177e4 LT |
1184 | |
1185 | s32 i2c_smbus_read_byte(struct i2c_client *client) | |
1186 | { | |
1187 | union i2c_smbus_data data; | |
1188 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1189 | I2C_SMBUS_READ,0,I2C_SMBUS_BYTE, &data)) | |
1190 | return -1; | |
1191 | else | |
7eff82c8 | 1192 | return data.byte; |
1da177e4 | 1193 | } |
c0564606 | 1194 | EXPORT_SYMBOL(i2c_smbus_read_byte); |
1da177e4 LT |
1195 | |
1196 | s32 i2c_smbus_write_byte(struct i2c_client *client, u8 value) | |
1197 | { | |
1da177e4 | 1198 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
421ef47b | 1199 | I2C_SMBUS_WRITE, value, I2C_SMBUS_BYTE, NULL); |
1da177e4 | 1200 | } |
c0564606 | 1201 | EXPORT_SYMBOL(i2c_smbus_write_byte); |
1da177e4 LT |
1202 | |
1203 | s32 i2c_smbus_read_byte_data(struct i2c_client *client, u8 command) | |
1204 | { | |
1205 | union i2c_smbus_data data; | |
1206 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1207 | I2C_SMBUS_READ,command, I2C_SMBUS_BYTE_DATA,&data)) | |
1208 | return -1; | |
1209 | else | |
7eff82c8 | 1210 | return data.byte; |
1da177e4 | 1211 | } |
c0564606 | 1212 | EXPORT_SYMBOL(i2c_smbus_read_byte_data); |
1da177e4 LT |
1213 | |
1214 | s32 i2c_smbus_write_byte_data(struct i2c_client *client, u8 command, u8 value) | |
1215 | { | |
1216 | union i2c_smbus_data data; | |
1217 | data.byte = value; | |
1218 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1219 | I2C_SMBUS_WRITE,command, | |
1220 | I2C_SMBUS_BYTE_DATA,&data); | |
1221 | } | |
c0564606 | 1222 | EXPORT_SYMBOL(i2c_smbus_write_byte_data); |
1da177e4 LT |
1223 | |
1224 | s32 i2c_smbus_read_word_data(struct i2c_client *client, u8 command) | |
1225 | { | |
1226 | union i2c_smbus_data data; | |
1227 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1228 | I2C_SMBUS_READ,command, I2C_SMBUS_WORD_DATA, &data)) | |
1229 | return -1; | |
1230 | else | |
7eff82c8 | 1231 | return data.word; |
1da177e4 | 1232 | } |
c0564606 | 1233 | EXPORT_SYMBOL(i2c_smbus_read_word_data); |
1da177e4 LT |
1234 | |
1235 | s32 i2c_smbus_write_word_data(struct i2c_client *client, u8 command, u16 value) | |
1236 | { | |
1237 | union i2c_smbus_data data; | |
1238 | data.word = value; | |
1239 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, | |
1240 | I2C_SMBUS_WRITE,command, | |
1241 | I2C_SMBUS_WORD_DATA,&data); | |
1242 | } | |
c0564606 | 1243 | EXPORT_SYMBOL(i2c_smbus_write_word_data); |
1da177e4 | 1244 | |
a64ec07d DB |
1245 | /** |
1246 | * i2c_smbus_read_block_data - SMBus block read request | |
1247 | * @client: Handle to slave device | |
1248 | * @command: Command byte issued to let the slave know what data should | |
1249 | * be returned | |
1250 | * @values: Byte array into which data will be read; big enough to hold | |
1251 | * the data returned by the slave. SMBus allows at most 32 bytes. | |
1252 | * | |
1253 | * Returns the number of bytes read in the slave's response, else a | |
1254 | * negative number to indicate some kind of error. | |
1255 | * | |
1256 | * Note that using this function requires that the client's adapter support | |
1257 | * the I2C_FUNC_SMBUS_READ_BLOCK_DATA functionality. Not all adapter drivers | |
1258 | * support this; its emulation through I2C messaging relies on a specific | |
1259 | * mechanism (I2C_M_RECV_LEN) which may not be implemented. | |
1260 | */ | |
b86a1bc8 JD |
1261 | s32 i2c_smbus_read_block_data(struct i2c_client *client, u8 command, |
1262 | u8 *values) | |
1263 | { | |
1264 | union i2c_smbus_data data; | |
1265 | ||
1266 | if (i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1267 | I2C_SMBUS_READ, command, | |
1268 | I2C_SMBUS_BLOCK_DATA, &data)) | |
1269 | return -1; | |
1270 | ||
1271 | memcpy(values, &data.block[1], data.block[0]); | |
1272 | return data.block[0]; | |
1273 | } | |
1274 | EXPORT_SYMBOL(i2c_smbus_read_block_data); | |
1275 | ||
1da177e4 | 1276 | s32 i2c_smbus_write_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1277 | u8 length, const u8 *values) |
1da177e4 LT |
1278 | { |
1279 | union i2c_smbus_data data; | |
7656032b | 1280 | |
1da177e4 LT |
1281 | if (length > I2C_SMBUS_BLOCK_MAX) |
1282 | length = I2C_SMBUS_BLOCK_MAX; | |
1da177e4 | 1283 | data.block[0] = length; |
7656032b | 1284 | memcpy(&data.block[1], values, length); |
1da177e4 LT |
1285 | return i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
1286 | I2C_SMBUS_WRITE,command, | |
1287 | I2C_SMBUS_BLOCK_DATA,&data); | |
1288 | } | |
c0564606 | 1289 | EXPORT_SYMBOL(i2c_smbus_write_block_data); |
1da177e4 LT |
1290 | |
1291 | /* Returns the number of read bytes */ | |
4b2643d7 JD |
1292 | s32 i2c_smbus_read_i2c_block_data(struct i2c_client *client, u8 command, |
1293 | u8 length, u8 *values) | |
1da177e4 LT |
1294 | { |
1295 | union i2c_smbus_data data; | |
7656032b | 1296 | |
4b2643d7 JD |
1297 | if (length > I2C_SMBUS_BLOCK_MAX) |
1298 | length = I2C_SMBUS_BLOCK_MAX; | |
1299 | data.block[0] = length; | |
1da177e4 LT |
1300 | if (i2c_smbus_xfer(client->adapter,client->addr,client->flags, |
1301 | I2C_SMBUS_READ,command, | |
1302 | I2C_SMBUS_I2C_BLOCK_DATA,&data)) | |
1303 | return -1; | |
7656032b JD |
1304 | |
1305 | memcpy(values, &data.block[1], data.block[0]); | |
1306 | return data.block[0]; | |
1da177e4 | 1307 | } |
c0564606 | 1308 | EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data); |
1da177e4 | 1309 | |
21bbd691 | 1310 | s32 i2c_smbus_write_i2c_block_data(struct i2c_client *client, u8 command, |
46f5ed75 | 1311 | u8 length, const u8 *values) |
21bbd691 JD |
1312 | { |
1313 | union i2c_smbus_data data; | |
1314 | ||
1315 | if (length > I2C_SMBUS_BLOCK_MAX) | |
1316 | length = I2C_SMBUS_BLOCK_MAX; | |
1317 | data.block[0] = length; | |
1318 | memcpy(data.block + 1, values, length); | |
1319 | return i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
1320 | I2C_SMBUS_WRITE, command, | |
1321 | I2C_SMBUS_I2C_BLOCK_DATA, &data); | |
1322 | } | |
c0564606 | 1323 | EXPORT_SYMBOL(i2c_smbus_write_i2c_block_data); |
21bbd691 | 1324 | |
438d6c2c | 1325 | /* Simulate a SMBus command using the i2c protocol |
1da177e4 | 1326 | No checking of parameters is done! */ |
438d6c2c | 1327 | static s32 i2c_smbus_xfer_emulated(struct i2c_adapter * adapter, u16 addr, |
1da177e4 | 1328 | unsigned short flags, |
438d6c2c | 1329 | char read_write, u8 command, int size, |
1da177e4 LT |
1330 | union i2c_smbus_data * data) |
1331 | { | |
1332 | /* So we need to generate a series of msgs. In the case of writing, we | |
1333 | need to use only one message; when reading, we need two. We initialize | |
1334 | most things with sane defaults, to keep the code below somewhat | |
1335 | simpler. */ | |
5c50d188 HI |
1336 | unsigned char msgbuf0[I2C_SMBUS_BLOCK_MAX+3]; |
1337 | unsigned char msgbuf1[I2C_SMBUS_BLOCK_MAX+2]; | |
1da177e4 | 1338 | int num = read_write == I2C_SMBUS_READ?2:1; |
438d6c2c | 1339 | struct i2c_msg msg[2] = { { addr, flags, 1, msgbuf0 }, |
1da177e4 LT |
1340 | { addr, flags | I2C_M_RD, 0, msgbuf1 } |
1341 | }; | |
1342 | int i; | |
421ef47b | 1343 | u8 partial_pec = 0; |
1da177e4 LT |
1344 | |
1345 | msgbuf0[0] = command; | |
1346 | switch(size) { | |
1347 | case I2C_SMBUS_QUICK: | |
1348 | msg[0].len = 0; | |
1349 | /* Special case: The read/write field is used as data */ | |
1350 | msg[0].flags = flags | (read_write==I2C_SMBUS_READ)?I2C_M_RD:0; | |
1351 | num = 1; | |
1352 | break; | |
1353 | case I2C_SMBUS_BYTE: | |
1354 | if (read_write == I2C_SMBUS_READ) { | |
1355 | /* Special case: only a read! */ | |
1356 | msg[0].flags = I2C_M_RD | flags; | |
1357 | num = 1; | |
1358 | } | |
1359 | break; | |
1360 | case I2C_SMBUS_BYTE_DATA: | |
1361 | if (read_write == I2C_SMBUS_READ) | |
1362 | msg[1].len = 1; | |
1363 | else { | |
1364 | msg[0].len = 2; | |
1365 | msgbuf0[1] = data->byte; | |
1366 | } | |
1367 | break; | |
1368 | case I2C_SMBUS_WORD_DATA: | |
1369 | if (read_write == I2C_SMBUS_READ) | |
1370 | msg[1].len = 2; | |
1371 | else { | |
1372 | msg[0].len=3; | |
1373 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1374 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1375 | } |
1376 | break; | |
1377 | case I2C_SMBUS_PROC_CALL: | |
1378 | num = 2; /* Special case */ | |
1379 | read_write = I2C_SMBUS_READ; | |
1380 | msg[0].len = 3; | |
1381 | msg[1].len = 2; | |
1382 | msgbuf0[1] = data->word & 0xff; | |
7eff82c8 | 1383 | msgbuf0[2] = data->word >> 8; |
1da177e4 LT |
1384 | break; |
1385 | case I2C_SMBUS_BLOCK_DATA: | |
1da177e4 | 1386 | if (read_write == I2C_SMBUS_READ) { |
209d27c3 JD |
1387 | msg[1].flags |= I2C_M_RECV_LEN; |
1388 | msg[1].len = 1; /* block length will be added by | |
1389 | the underlying bus driver */ | |
1da177e4 LT |
1390 | } else { |
1391 | msg[0].len = data->block[0] + 2; | |
1392 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 2) { | |
1393 | dev_err(&adapter->dev, "smbus_access called with " | |
1394 | "invalid block write size (%d)\n", | |
1395 | data->block[0]); | |
1396 | return -1; | |
1397 | } | |
5c50d188 | 1398 | for (i = 1; i < msg[0].len; i++) |
1da177e4 LT |
1399 | msgbuf0[i] = data->block[i-1]; |
1400 | } | |
1401 | break; | |
1402 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
209d27c3 JD |
1403 | num = 2; /* Another special case */ |
1404 | read_write = I2C_SMBUS_READ; | |
1405 | if (data->block[0] > I2C_SMBUS_BLOCK_MAX) { | |
1406 | dev_err(&adapter->dev, "%s called with invalid " | |
1407 | "block proc call size (%d)\n", __FUNCTION__, | |
1408 | data->block[0]); | |
1409 | return -1; | |
1410 | } | |
1411 | msg[0].len = data->block[0] + 2; | |
1412 | for (i = 1; i < msg[0].len; i++) | |
1413 | msgbuf0[i] = data->block[i-1]; | |
1414 | msg[1].flags |= I2C_M_RECV_LEN; | |
1415 | msg[1].len = 1; /* block length will be added by | |
1416 | the underlying bus driver */ | |
1417 | break; | |
1da177e4 LT |
1418 | case I2C_SMBUS_I2C_BLOCK_DATA: |
1419 | if (read_write == I2C_SMBUS_READ) { | |
4b2643d7 | 1420 | msg[1].len = data->block[0]; |
1da177e4 LT |
1421 | } else { |
1422 | msg[0].len = data->block[0] + 1; | |
30dac746 | 1423 | if (msg[0].len > I2C_SMBUS_BLOCK_MAX + 1) { |
1da177e4 LT |
1424 | dev_err(&adapter->dev, "i2c_smbus_xfer_emulated called with " |
1425 | "invalid block write size (%d)\n", | |
1426 | data->block[0]); | |
1427 | return -1; | |
1428 | } | |
1429 | for (i = 1; i <= data->block[0]; i++) | |
1430 | msgbuf0[i] = data->block[i]; | |
1431 | } | |
1432 | break; | |
1433 | default: | |
1434 | dev_err(&adapter->dev, "smbus_access called with invalid size (%d)\n", | |
1435 | size); | |
1436 | return -1; | |
1437 | } | |
1438 | ||
421ef47b JD |
1439 | i = ((flags & I2C_CLIENT_PEC) && size != I2C_SMBUS_QUICK |
1440 | && size != I2C_SMBUS_I2C_BLOCK_DATA); | |
1441 | if (i) { | |
1442 | /* Compute PEC if first message is a write */ | |
1443 | if (!(msg[0].flags & I2C_M_RD)) { | |
438d6c2c | 1444 | if (num == 1) /* Write only */ |
421ef47b JD |
1445 | i2c_smbus_add_pec(&msg[0]); |
1446 | else /* Write followed by read */ | |
1447 | partial_pec = i2c_smbus_msg_pec(0, &msg[0]); | |
1448 | } | |
1449 | /* Ask for PEC if last message is a read */ | |
1450 | if (msg[num-1].flags & I2C_M_RD) | |
438d6c2c | 1451 | msg[num-1].len++; |
421ef47b JD |
1452 | } |
1453 | ||
1da177e4 LT |
1454 | if (i2c_transfer(adapter, msg, num) < 0) |
1455 | return -1; | |
1456 | ||
421ef47b JD |
1457 | /* Check PEC if last message is a read */ |
1458 | if (i && (msg[num-1].flags & I2C_M_RD)) { | |
1459 | if (i2c_smbus_check_pec(partial_pec, &msg[num-1]) < 0) | |
1460 | return -1; | |
1461 | } | |
1462 | ||
1da177e4 LT |
1463 | if (read_write == I2C_SMBUS_READ) |
1464 | switch(size) { | |
1465 | case I2C_SMBUS_BYTE: | |
1466 | data->byte = msgbuf0[0]; | |
1467 | break; | |
1468 | case I2C_SMBUS_BYTE_DATA: | |
1469 | data->byte = msgbuf1[0]; | |
1470 | break; | |
438d6c2c | 1471 | case I2C_SMBUS_WORD_DATA: |
1da177e4 LT |
1472 | case I2C_SMBUS_PROC_CALL: |
1473 | data->word = msgbuf1[0] | (msgbuf1[1] << 8); | |
1474 | break; | |
1475 | case I2C_SMBUS_I2C_BLOCK_DATA: | |
4b2643d7 | 1476 | for (i = 0; i < data->block[0]; i++) |
1da177e4 LT |
1477 | data->block[i+1] = msgbuf1[i]; |
1478 | break; | |
209d27c3 JD |
1479 | case I2C_SMBUS_BLOCK_DATA: |
1480 | case I2C_SMBUS_BLOCK_PROC_CALL: | |
1481 | for (i = 0; i < msgbuf1[0] + 1; i++) | |
1482 | data->block[i] = msgbuf1[i]; | |
1483 | break; | |
1da177e4 LT |
1484 | } |
1485 | return 0; | |
1486 | } | |
1487 | ||
1488 | ||
1489 | s32 i2c_smbus_xfer(struct i2c_adapter * adapter, u16 addr, unsigned short flags, | |
438d6c2c | 1490 | char read_write, u8 command, int size, |
1da177e4 LT |
1491 | union i2c_smbus_data * data) |
1492 | { | |
1493 | s32 res; | |
1da177e4 LT |
1494 | |
1495 | flags &= I2C_M_TEN | I2C_CLIENT_PEC; | |
1da177e4 LT |
1496 | |
1497 | if (adapter->algo->smbus_xfer) { | |
5c085d36 | 1498 | mutex_lock(&adapter->bus_lock); |
1da177e4 LT |
1499 | res = adapter->algo->smbus_xfer(adapter,addr,flags,read_write, |
1500 | command,size,data); | |
5c085d36 | 1501 | mutex_unlock(&adapter->bus_lock); |
1da177e4 LT |
1502 | } else |
1503 | res = i2c_smbus_xfer_emulated(adapter,addr,flags,read_write, | |
1504 | command,size,data); | |
1505 | ||
1da177e4 LT |
1506 | return res; |
1507 | } | |
1da177e4 | 1508 | EXPORT_SYMBOL(i2c_smbus_xfer); |
1da177e4 LT |
1509 | |
1510 | MODULE_AUTHOR("Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
1511 | MODULE_DESCRIPTION("I2C-Bus main module"); | |
1512 | MODULE_LICENSE("GPL"); |