Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
438d6c2c | 2 | i2c-dev.c - i2c-bus driver, char device interface |
1da177e4 LT |
3 | |
4 | Copyright (C) 1995-97 Simon G. Vogl | |
5 | Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl> | |
6 | Copyright (C) 2003 Greg Kroah-Hartman <greg@kroah.com> | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 2 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with this program; if not, write to the Free Software | |
20 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | |
21 | */ | |
22 | ||
23 | /* Note that this is a complete rewrite of Simon Vogl's i2c-dev module. | |
24 | But I have used so much of his original code and ideas that it seems | |
25 | only fair to recognize him as co-author -- Frodo */ | |
26 | ||
27 | /* The I2C_RDWR ioctl code is written by Kolja Waschk <waschk@telos.de> */ | |
28 | ||
1da177e4 LT |
29 | #include <linux/kernel.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/fs.h> | |
32 | #include <linux/slab.h> | |
1da177e4 | 33 | #include <linux/init.h> |
f3b3aadb | 34 | #include <linux/list.h> |
1da177e4 LT |
35 | #include <linux/i2c.h> |
36 | #include <linux/i2c-dev.h> | |
3db633ee | 37 | #include <linux/smp_lock.h> |
cd97f39b | 38 | #include <linux/jiffies.h> |
1da177e4 LT |
39 | #include <asm/uaccess.h> |
40 | ||
22f76e74 | 41 | static struct i2c_driver i2cdev_driver; |
1da177e4 | 42 | |
907135aa DB |
43 | /* |
44 | * An i2c_dev represents an i2c_adapter ... an I2C or SMBus master, not a | |
45 | * slave (i2c_client) with which messages will be exchanged. It's coupled | |
46 | * with a character special file which is accessed by user mode drivers. | |
47 | * | |
48 | * The list of i2c_dev structures is parallel to the i2c_adapter lists | |
49 | * maintained by the driver model, and is updated using notifications | |
50 | * delivered to the i2cdev_driver. | |
51 | */ | |
1da177e4 | 52 | struct i2c_dev { |
f3b3aadb | 53 | struct list_head list; |
1da177e4 | 54 | struct i2c_adapter *adap; |
ac11d060 | 55 | struct device *dev; |
1da177e4 | 56 | }; |
1da177e4 LT |
57 | |
58 | #define I2C_MINORS 256 | |
f3b3aadb JD |
59 | static LIST_HEAD(i2c_dev_list); |
60 | static DEFINE_SPINLOCK(i2c_dev_list_lock); | |
1da177e4 LT |
61 | |
62 | static struct i2c_dev *i2c_dev_get_by_minor(unsigned index) | |
63 | { | |
64 | struct i2c_dev *i2c_dev; | |
65 | ||
f3b3aadb JD |
66 | spin_lock(&i2c_dev_list_lock); |
67 | list_for_each_entry(i2c_dev, &i2c_dev_list, list) { | |
68 | if (i2c_dev->adap->nr == index) | |
69 | goto found; | |
70 | } | |
71 | i2c_dev = NULL; | |
72 | found: | |
73 | spin_unlock(&i2c_dev_list_lock); | |
1da177e4 LT |
74 | return i2c_dev; |
75 | } | |
76 | ||
1da177e4 LT |
77 | static struct i2c_dev *get_free_i2c_dev(struct i2c_adapter *adap) |
78 | { | |
79 | struct i2c_dev *i2c_dev; | |
80 | ||
f3b3aadb JD |
81 | if (adap->nr >= I2C_MINORS) { |
82 | printk(KERN_ERR "i2c-dev: Out of device minors (%d)\n", | |
83 | adap->nr); | |
84 | return ERR_PTR(-ENODEV); | |
85 | } | |
86 | ||
5263ebb5 | 87 | i2c_dev = kzalloc(sizeof(*i2c_dev), GFP_KERNEL); |
1da177e4 LT |
88 | if (!i2c_dev) |
89 | return ERR_PTR(-ENOMEM); | |
9455e4c9 | 90 | i2c_dev->adap = adap; |
f3b3aadb JD |
91 | |
92 | spin_lock(&i2c_dev_list_lock); | |
93 | list_add_tail(&i2c_dev->list, &i2c_dev_list); | |
94 | spin_unlock(&i2c_dev_list_lock); | |
1da177e4 | 95 | return i2c_dev; |
1da177e4 LT |
96 | } |
97 | ||
98 | static void return_i2c_dev(struct i2c_dev *i2c_dev) | |
99 | { | |
f3b3aadb JD |
100 | spin_lock(&i2c_dev_list_lock); |
101 | list_del(&i2c_dev->list); | |
102 | spin_unlock(&i2c_dev_list_lock); | |
07125ab2 | 103 | kfree(i2c_dev); |
1da177e4 LT |
104 | } |
105 | ||
ac11d060 GKH |
106 | static ssize_t show_adapter_name(struct device *dev, |
107 | struct device_attribute *attr, char *buf) | |
1da177e4 | 108 | { |
ac11d060 | 109 | struct i2c_dev *i2c_dev = i2c_dev_get_by_minor(MINOR(dev->devt)); |
79472132 GKH |
110 | |
111 | if (!i2c_dev) | |
112 | return -ENODEV; | |
1da177e4 LT |
113 | return sprintf(buf, "%s\n", i2c_dev->adap->name); |
114 | } | |
ac11d060 | 115 | static DEVICE_ATTR(name, S_IRUGO, show_adapter_name, NULL); |
1da177e4 | 116 | |
907135aa DB |
117 | /* ------------------------------------------------------------------------- */ |
118 | ||
119 | /* | |
120 | * After opening an instance of this character special file, a file | |
121 | * descriptor starts out associated only with an i2c_adapter (and bus). | |
122 | * | |
123 | * Using the I2C_RDWR ioctl(), you can then *immediately* issue i2c_msg | |
124 | * traffic to any devices on the bus used by that adapter. That's because | |
125 | * the i2c_msg vectors embed all the addressing information they need, and | |
126 | * are submitted directly to an i2c_adapter. However, SMBus-only adapters | |
127 | * don't support that interface. | |
128 | * | |
129 | * To use read()/write() system calls on that file descriptor, or to use | |
130 | * SMBus interfaces (and work with SMBus-only hosts!), you must first issue | |
131 | * an I2C_SLAVE (or I2C_SLAVE_FORCE) ioctl. That configures an anonymous | |
132 | * (never registered) i2c_client so it holds the addressing information | |
133 | * needed by those system calls and by this SMBus interface. | |
134 | */ | |
135 | ||
1da177e4 LT |
136 | static ssize_t i2cdev_read (struct file *file, char __user *buf, size_t count, |
137 | loff_t *offset) | |
138 | { | |
139 | char *tmp; | |
140 | int ret; | |
141 | ||
142 | struct i2c_client *client = (struct i2c_client *)file->private_data; | |
143 | ||
144 | if (count > 8192) | |
145 | count = 8192; | |
146 | ||
147 | tmp = kmalloc(count,GFP_KERNEL); | |
148 | if (tmp==NULL) | |
149 | return -ENOMEM; | |
150 | ||
2ce5b34f | 151 | pr_debug("i2c-dev: i2c-%d reading %zu bytes.\n", |
cba0a128 | 152 | iminor(file->f_path.dentry->d_inode), count); |
1da177e4 LT |
153 | |
154 | ret = i2c_master_recv(client,tmp,count); | |
155 | if (ret >= 0) | |
156 | ret = copy_to_user(buf,tmp,count)?-EFAULT:ret; | |
157 | kfree(tmp); | |
158 | return ret; | |
159 | } | |
160 | ||
161 | static ssize_t i2cdev_write (struct file *file, const char __user *buf, size_t count, | |
162 | loff_t *offset) | |
163 | { | |
164 | int ret; | |
165 | char *tmp; | |
166 | struct i2c_client *client = (struct i2c_client *)file->private_data; | |
167 | ||
168 | if (count > 8192) | |
169 | count = 8192; | |
170 | ||
171 | tmp = kmalloc(count,GFP_KERNEL); | |
172 | if (tmp==NULL) | |
173 | return -ENOMEM; | |
174 | if (copy_from_user(tmp,buf,count)) { | |
175 | kfree(tmp); | |
176 | return -EFAULT; | |
177 | } | |
178 | ||
2ce5b34f | 179 | pr_debug("i2c-dev: i2c-%d writing %zu bytes.\n", |
cba0a128 | 180 | iminor(file->f_path.dentry->d_inode), count); |
1da177e4 LT |
181 | |
182 | ret = i2c_master_send(client,tmp,count); | |
183 | kfree(tmp); | |
184 | return ret; | |
185 | } | |
186 | ||
9b766b81 DB |
187 | static int i2cdev_check(struct device *dev, void *addrp) |
188 | { | |
189 | struct i2c_client *client = i2c_verify_client(dev); | |
190 | ||
191 | if (!client || client->addr != *(unsigned int *)addrp) | |
192 | return 0; | |
193 | ||
194 | return dev->driver ? -EBUSY : 0; | |
195 | } | |
196 | ||
bd4217d8 JD |
197 | /* This address checking function differs from the one in i2c-core |
198 | in that it considers an address with a registered device, but no | |
9b766b81 | 199 | driver bound to it, as NOT busy. */ |
bd4217d8 JD |
200 | static int i2cdev_check_addr(struct i2c_adapter *adapter, unsigned int addr) |
201 | { | |
9b766b81 | 202 | return device_for_each_child(&adapter->dev, &addr, i2cdev_check); |
bd4217d8 JD |
203 | } |
204 | ||
dba7997a JD |
205 | static noinline int i2cdev_ioctl_rdrw(struct i2c_client *client, |
206 | unsigned long arg) | |
1da177e4 | 207 | { |
1da177e4 | 208 | struct i2c_rdwr_ioctl_data rdwr_arg; |
1da177e4 LT |
209 | struct i2c_msg *rdwr_pa; |
210 | u8 __user **data_ptrs; | |
dba7997a JD |
211 | int i, res; |
212 | ||
213 | if (copy_from_user(&rdwr_arg, | |
214 | (struct i2c_rdwr_ioctl_data __user *)arg, | |
215 | sizeof(rdwr_arg))) | |
216 | return -EFAULT; | |
217 | ||
218 | /* Put an arbitrary limit on the number of messages that can | |
219 | * be sent at once */ | |
220 | if (rdwr_arg.nmsgs > I2C_RDRW_IOCTL_MAX_MSGS) | |
221 | return -EINVAL; | |
222 | ||
223 | rdwr_pa = (struct i2c_msg *) | |
224 | kmalloc(rdwr_arg.nmsgs * sizeof(struct i2c_msg), | |
225 | GFP_KERNEL); | |
226 | if (!rdwr_pa) | |
227 | return -ENOMEM; | |
228 | ||
229 | if (copy_from_user(rdwr_pa, rdwr_arg.msgs, | |
230 | rdwr_arg.nmsgs * sizeof(struct i2c_msg))) { | |
231 | kfree(rdwr_pa); | |
232 | return -EFAULT; | |
233 | } | |
234 | ||
235 | data_ptrs = kmalloc(rdwr_arg.nmsgs * sizeof(u8 __user *), GFP_KERNEL); | |
236 | if (data_ptrs == NULL) { | |
237 | kfree(rdwr_pa); | |
238 | return -ENOMEM; | |
239 | } | |
240 | ||
241 | res = 0; | |
242 | for (i = 0; i < rdwr_arg.nmsgs; i++) { | |
243 | /* Limit the size of the message to a sane amount; | |
244 | * and don't let length change either. */ | |
245 | if ((rdwr_pa[i].len > 8192) || | |
246 | (rdwr_pa[i].flags & I2C_M_RECV_LEN)) { | |
247 | res = -EINVAL; | |
248 | break; | |
249 | } | |
250 | data_ptrs[i] = (u8 __user *)rdwr_pa[i].buf; | |
251 | rdwr_pa[i].buf = kmalloc(rdwr_pa[i].len, GFP_KERNEL); | |
252 | if (rdwr_pa[i].buf == NULL) { | |
253 | res = -ENOMEM; | |
254 | break; | |
255 | } | |
256 | if (copy_from_user(rdwr_pa[i].buf, data_ptrs[i], | |
257 | rdwr_pa[i].len)) { | |
258 | ++i; /* Needs to be kfreed too */ | |
259 | res = -EFAULT; | |
260 | break; | |
261 | } | |
262 | } | |
263 | if (res < 0) { | |
264 | int j; | |
265 | for (j = 0; j < i; ++j) | |
266 | kfree(rdwr_pa[j].buf); | |
267 | kfree(data_ptrs); | |
268 | kfree(rdwr_pa); | |
269 | return res; | |
270 | } | |
271 | ||
272 | res = i2c_transfer(client->adapter, rdwr_pa, rdwr_arg.nmsgs); | |
273 | while (i-- > 0) { | |
274 | if (res >= 0 && (rdwr_pa[i].flags & I2C_M_RD)) { | |
275 | if (copy_to_user(data_ptrs[i], rdwr_pa[i].buf, | |
276 | rdwr_pa[i].len)) | |
277 | res = -EFAULT; | |
278 | } | |
279 | kfree(rdwr_pa[i].buf); | |
280 | } | |
281 | kfree(data_ptrs); | |
282 | kfree(rdwr_pa); | |
283 | return res; | |
284 | } | |
285 | ||
286 | static noinline int i2cdev_ioctl_smbus(struct i2c_client *client, | |
287 | unsigned long arg) | |
288 | { | |
289 | struct i2c_smbus_ioctl_data data_arg; | |
290 | union i2c_smbus_data temp; | |
291 | int datasize, res; | |
292 | ||
293 | if (copy_from_user(&data_arg, | |
294 | (struct i2c_smbus_ioctl_data __user *) arg, | |
295 | sizeof(struct i2c_smbus_ioctl_data))) | |
296 | return -EFAULT; | |
297 | if ((data_arg.size != I2C_SMBUS_BYTE) && | |
298 | (data_arg.size != I2C_SMBUS_QUICK) && | |
299 | (data_arg.size != I2C_SMBUS_BYTE_DATA) && | |
300 | (data_arg.size != I2C_SMBUS_WORD_DATA) && | |
301 | (data_arg.size != I2C_SMBUS_PROC_CALL) && | |
302 | (data_arg.size != I2C_SMBUS_BLOCK_DATA) && | |
303 | (data_arg.size != I2C_SMBUS_I2C_BLOCK_BROKEN) && | |
304 | (data_arg.size != I2C_SMBUS_I2C_BLOCK_DATA) && | |
305 | (data_arg.size != I2C_SMBUS_BLOCK_PROC_CALL)) { | |
306 | dev_dbg(&client->adapter->dev, | |
307 | "size out of range (%x) in ioctl I2C_SMBUS.\n", | |
308 | data_arg.size); | |
309 | return -EINVAL; | |
310 | } | |
311 | /* Note that I2C_SMBUS_READ and I2C_SMBUS_WRITE are 0 and 1, | |
312 | so the check is valid if size==I2C_SMBUS_QUICK too. */ | |
313 | if ((data_arg.read_write != I2C_SMBUS_READ) && | |
314 | (data_arg.read_write != I2C_SMBUS_WRITE)) { | |
315 | dev_dbg(&client->adapter->dev, | |
316 | "read_write out of range (%x) in ioctl I2C_SMBUS.\n", | |
317 | data_arg.read_write); | |
318 | return -EINVAL; | |
319 | } | |
320 | ||
321 | /* Note that command values are always valid! */ | |
322 | ||
323 | if ((data_arg.size == I2C_SMBUS_QUICK) || | |
324 | ((data_arg.size == I2C_SMBUS_BYTE) && | |
325 | (data_arg.read_write == I2C_SMBUS_WRITE))) | |
326 | /* These are special: we do not use data */ | |
327 | return i2c_smbus_xfer(client->adapter, client->addr, | |
328 | client->flags, data_arg.read_write, | |
329 | data_arg.command, data_arg.size, NULL); | |
330 | ||
331 | if (data_arg.data == NULL) { | |
332 | dev_dbg(&client->adapter->dev, | |
333 | "data is NULL pointer in ioctl I2C_SMBUS.\n"); | |
334 | return -EINVAL; | |
335 | } | |
336 | ||
337 | if ((data_arg.size == I2C_SMBUS_BYTE_DATA) || | |
338 | (data_arg.size == I2C_SMBUS_BYTE)) | |
339 | datasize = sizeof(data_arg.data->byte); | |
340 | else if ((data_arg.size == I2C_SMBUS_WORD_DATA) || | |
341 | (data_arg.size == I2C_SMBUS_PROC_CALL)) | |
342 | datasize = sizeof(data_arg.data->word); | |
343 | else /* size == smbus block, i2c block, or block proc. call */ | |
344 | datasize = sizeof(data_arg.data->block); | |
345 | ||
346 | if ((data_arg.size == I2C_SMBUS_PROC_CALL) || | |
347 | (data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) || | |
348 | (data_arg.size == I2C_SMBUS_I2C_BLOCK_DATA) || | |
349 | (data_arg.read_write == I2C_SMBUS_WRITE)) { | |
350 | if (copy_from_user(&temp, data_arg.data, datasize)) | |
351 | return -EFAULT; | |
352 | } | |
353 | if (data_arg.size == I2C_SMBUS_I2C_BLOCK_BROKEN) { | |
354 | /* Convert old I2C block commands to the new | |
355 | convention. This preserves binary compatibility. */ | |
356 | data_arg.size = I2C_SMBUS_I2C_BLOCK_DATA; | |
357 | if (data_arg.read_write == I2C_SMBUS_READ) | |
358 | temp.block[0] = I2C_SMBUS_BLOCK_MAX; | |
359 | } | |
360 | res = i2c_smbus_xfer(client->adapter, client->addr, client->flags, | |
361 | data_arg.read_write, data_arg.command, data_arg.size, &temp); | |
362 | if (!res && ((data_arg.size == I2C_SMBUS_PROC_CALL) || | |
363 | (data_arg.size == I2C_SMBUS_BLOCK_PROC_CALL) || | |
364 | (data_arg.read_write == I2C_SMBUS_READ))) { | |
365 | if (copy_to_user(data_arg.data, &temp, datasize)) | |
366 | return -EFAULT; | |
367 | } | |
368 | return res; | |
369 | } | |
370 | ||
77e38bff | 371 | static long i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) |
dba7997a JD |
372 | { |
373 | struct i2c_client *client = (struct i2c_client *)file->private_data; | |
1da177e4 LT |
374 | unsigned long funcs; |
375 | ||
e8aafcb2 JD |
376 | dev_dbg(&client->adapter->dev, "ioctl, cmd=0x%02x, arg=0x%02lx\n", |
377 | cmd, arg); | |
1da177e4 LT |
378 | |
379 | switch ( cmd ) { | |
380 | case I2C_SLAVE: | |
381 | case I2C_SLAVE_FORCE: | |
907135aa DB |
382 | /* NOTE: devices set up to work with "new style" drivers |
383 | * can't use I2C_SLAVE, even when the device node is not | |
384 | * bound to a driver. Only I2C_SLAVE_FORCE will work. | |
385 | * | |
386 | * Setting the PEC flag here won't affect kernel drivers, | |
387 | * which will be using the i2c_client node registered with | |
388 | * the driver model core. Likewise, when that client has | |
389 | * the PEC flag already set, the i2c-dev driver won't see | |
390 | * (or use) this setting. | |
391 | */ | |
438d6c2c | 392 | if ((arg > 0x3ff) || |
1da177e4 LT |
393 | (((client->flags & I2C_M_TEN) == 0) && arg > 0x7f)) |
394 | return -EINVAL; | |
bd4217d8 | 395 | if (cmd == I2C_SLAVE && i2cdev_check_addr(client->adapter, arg)) |
1da177e4 | 396 | return -EBUSY; |
bd4217d8 | 397 | /* REVISIT: address could become busy later */ |
1da177e4 LT |
398 | client->addr = arg; |
399 | return 0; | |
400 | case I2C_TENBIT: | |
401 | if (arg) | |
402 | client->flags |= I2C_M_TEN; | |
403 | else | |
404 | client->flags &= ~I2C_M_TEN; | |
405 | return 0; | |
406 | case I2C_PEC: | |
407 | if (arg) | |
408 | client->flags |= I2C_CLIENT_PEC; | |
409 | else | |
410 | client->flags &= ~I2C_CLIENT_PEC; | |
411 | return 0; | |
412 | case I2C_FUNCS: | |
413 | funcs = i2c_get_functionality(client->adapter); | |
2c003e8e | 414 | return put_user(funcs, (unsigned long __user *)arg); |
1da177e4 LT |
415 | |
416 | case I2C_RDWR: | |
dba7997a | 417 | return i2cdev_ioctl_rdrw(client, arg); |
1da177e4 LT |
418 | |
419 | case I2C_SMBUS: | |
dba7997a | 420 | return i2cdev_ioctl_smbus(client, arg); |
1da177e4 | 421 | |
53be7959 DB |
422 | case I2C_RETRIES: |
423 | client->adapter->retries = arg; | |
424 | break; | |
425 | case I2C_TIMEOUT: | |
cd97f39b JD |
426 | /* For historical reasons, user-space sets the timeout |
427 | * value in units of 10 ms. | |
428 | */ | |
429 | client->adapter->timeout = msecs_to_jiffies(arg * 10); | |
53be7959 | 430 | break; |
1da177e4 | 431 | default: |
53be7959 DB |
432 | /* NOTE: returning a fault code here could cause trouble |
433 | * in buggy userspace code. Some old kernel bugs returned | |
434 | * zero in this case, and userspace code might accidentally | |
435 | * have depended on that bug. | |
436 | */ | |
437 | return -ENOTTY; | |
1da177e4 LT |
438 | } |
439 | return 0; | |
440 | } | |
441 | ||
442 | static int i2cdev_open(struct inode *inode, struct file *file) | |
443 | { | |
444 | unsigned int minor = iminor(inode); | |
445 | struct i2c_client *client; | |
446 | struct i2c_adapter *adap; | |
447 | struct i2c_dev *i2c_dev; | |
3db633ee | 448 | int ret = 0; |
1da177e4 | 449 | |
3db633ee | 450 | lock_kernel(); |
1da177e4 | 451 | i2c_dev = i2c_dev_get_by_minor(minor); |
3db633ee JC |
452 | if (!i2c_dev) { |
453 | ret = -ENODEV; | |
454 | goto out; | |
455 | } | |
1da177e4 LT |
456 | |
457 | adap = i2c_get_adapter(i2c_dev->adap->nr); | |
3db633ee JC |
458 | if (!adap) { |
459 | ret = -ENODEV; | |
460 | goto out; | |
461 | } | |
1da177e4 | 462 | |
907135aa DB |
463 | /* This creates an anonymous i2c_client, which may later be |
464 | * pointed to some address using I2C_SLAVE or I2C_SLAVE_FORCE. | |
465 | * | |
466 | * This client is ** NEVER REGISTERED ** with the driver model | |
467 | * or I2C core code!! It just holds private copies of addressing | |
468 | * information and maybe a PEC flag. | |
469 | */ | |
22f76e74 | 470 | client = kzalloc(sizeof(*client), GFP_KERNEL); |
1da177e4 LT |
471 | if (!client) { |
472 | i2c_put_adapter(adap); | |
3db633ee JC |
473 | ret = -ENOMEM; |
474 | goto out; | |
1da177e4 | 475 | } |
22f76e74 JD |
476 | snprintf(client->name, I2C_NAME_SIZE, "i2c-dev %d", adap->nr); |
477 | client->driver = &i2cdev_driver; | |
1da177e4 | 478 | |
1da177e4 LT |
479 | client->adapter = adap; |
480 | file->private_data = client; | |
481 | ||
3db633ee JC |
482 | out: |
483 | unlock_kernel(); | |
484 | return ret; | |
1da177e4 LT |
485 | } |
486 | ||
487 | static int i2cdev_release(struct inode *inode, struct file *file) | |
488 | { | |
489 | struct i2c_client *client = file->private_data; | |
490 | ||
491 | i2c_put_adapter(client->adapter); | |
492 | kfree(client); | |
493 | file->private_data = NULL; | |
494 | ||
495 | return 0; | |
496 | } | |
497 | ||
2b8693c0 | 498 | static const struct file_operations i2cdev_fops = { |
1da177e4 LT |
499 | .owner = THIS_MODULE, |
500 | .llseek = no_llseek, | |
501 | .read = i2cdev_read, | |
502 | .write = i2cdev_write, | |
77e38bff | 503 | .unlocked_ioctl = i2cdev_ioctl, |
1da177e4 LT |
504 | .open = i2cdev_open, |
505 | .release = i2cdev_release, | |
506 | }; | |
507 | ||
907135aa DB |
508 | /* ------------------------------------------------------------------------- */ |
509 | ||
510 | /* | |
511 | * The legacy "i2cdev_driver" is used primarily to get notifications when | |
512 | * I2C adapters are added or removed, so that each one gets an i2c_dev | |
513 | * and is thus made available to userspace driver code. | |
514 | */ | |
515 | ||
79472132 | 516 | static struct class *i2c_dev_class; |
1da177e4 LT |
517 | |
518 | static int i2cdev_attach_adapter(struct i2c_adapter *adap) | |
519 | { | |
520 | struct i2c_dev *i2c_dev; | |
defcb46e | 521 | int res; |
1da177e4 LT |
522 | |
523 | i2c_dev = get_free_i2c_dev(adap); | |
524 | if (IS_ERR(i2c_dev)) | |
525 | return PTR_ERR(i2c_dev); | |
526 | ||
1da177e4 | 527 | /* register this i2c device with the driver core */ |
a9b12619 GKH |
528 | i2c_dev->dev = device_create(i2c_dev_class, &adap->dev, |
529 | MKDEV(I2C_MAJOR, adap->nr), NULL, | |
530 | "i2c-%d", adap->nr); | |
3bacb36d AM |
531 | if (IS_ERR(i2c_dev->dev)) { |
532 | res = PTR_ERR(i2c_dev->dev); | |
1da177e4 | 533 | goto error; |
defcb46e | 534 | } |
ac11d060 | 535 | res = device_create_file(i2c_dev->dev, &dev_attr_name); |
defcb46e JD |
536 | if (res) |
537 | goto error_destroy; | |
b32d20dc JD |
538 | |
539 | pr_debug("i2c-dev: adapter [%s] registered as minor %d\n", | |
540 | adap->name, adap->nr); | |
1da177e4 | 541 | return 0; |
defcb46e | 542 | error_destroy: |
ac11d060 | 543 | device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr)); |
1da177e4 LT |
544 | error: |
545 | return_i2c_dev(i2c_dev); | |
defcb46e | 546 | return res; |
1da177e4 LT |
547 | } |
548 | ||
549 | static int i2cdev_detach_adapter(struct i2c_adapter *adap) | |
550 | { | |
551 | struct i2c_dev *i2c_dev; | |
552 | ||
9455e4c9 | 553 | i2c_dev = i2c_dev_get_by_minor(adap->nr); |
b32d20dc JD |
554 | if (!i2c_dev) /* attach_adapter must have failed */ |
555 | return 0; | |
1da177e4 | 556 | |
ac11d060 | 557 | device_remove_file(i2c_dev->dev, &dev_attr_name); |
1da177e4 | 558 | return_i2c_dev(i2c_dev); |
ac11d060 | 559 | device_destroy(i2c_dev_class, MKDEV(I2C_MAJOR, adap->nr)); |
1da177e4 | 560 | |
b6d7b3d1 | 561 | pr_debug("i2c-dev: adapter [%s] unregistered\n", adap->name); |
1da177e4 LT |
562 | return 0; |
563 | } | |
564 | ||
1da177e4 | 565 | static struct i2c_driver i2cdev_driver = { |
35d8b2e6 | 566 | .driver = { |
35d8b2e6 LR |
567 | .name = "dev_driver", |
568 | }, | |
1da177e4 LT |
569 | .attach_adapter = i2cdev_attach_adapter, |
570 | .detach_adapter = i2cdev_detach_adapter, | |
1da177e4 LT |
571 | }; |
572 | ||
907135aa DB |
573 | /* ------------------------------------------------------------------------- */ |
574 | ||
575 | /* | |
576 | * module load/unload record keeping | |
577 | */ | |
578 | ||
1da177e4 LT |
579 | static int __init i2c_dev_init(void) |
580 | { | |
581 | int res; | |
582 | ||
583 | printk(KERN_INFO "i2c /dev entries driver\n"); | |
584 | ||
585 | res = register_chrdev(I2C_MAJOR, "i2c", &i2cdev_fops); | |
586 | if (res) | |
587 | goto out; | |
588 | ||
79472132 | 589 | i2c_dev_class = class_create(THIS_MODULE, "i2c-dev"); |
e74783ec SW |
590 | if (IS_ERR(i2c_dev_class)) { |
591 | res = PTR_ERR(i2c_dev_class); | |
1da177e4 | 592 | goto out_unreg_chrdev; |
e74783ec | 593 | } |
1da177e4 LT |
594 | |
595 | res = i2c_add_driver(&i2cdev_driver); | |
596 | if (res) | |
597 | goto out_unreg_class; | |
598 | ||
1da177e4 LT |
599 | return 0; |
600 | ||
601 | out_unreg_class: | |
79472132 | 602 | class_destroy(i2c_dev_class); |
1da177e4 LT |
603 | out_unreg_chrdev: |
604 | unregister_chrdev(I2C_MAJOR, "i2c"); | |
605 | out: | |
606 | printk(KERN_ERR "%s: Driver Initialisation failed\n", __FILE__); | |
607 | return res; | |
608 | } | |
609 | ||
610 | static void __exit i2c_dev_exit(void) | |
611 | { | |
612 | i2c_del_driver(&i2cdev_driver); | |
79472132 | 613 | class_destroy(i2c_dev_class); |
1da177e4 LT |
614 | unregister_chrdev(I2C_MAJOR,"i2c"); |
615 | } | |
616 | ||
617 | MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and " | |
618 | "Simon G. Vogl <simon@tk.uni-linz.ac.at>"); | |
619 | MODULE_DESCRIPTION("I2C /dev entries driver"); | |
620 | MODULE_LICENSE("GPL"); | |
621 | ||
622 | module_init(i2c_dev_init); | |
623 | module_exit(i2c_dev_exit); |