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mm: memcontrol: use per-cpu stocks for socket memory uncharging
[linux/fpc-iii.git] / drivers / hid / i2c-hid / i2c-hid.c
blob77396145d2d093af60e44c825ffaabd25f9b68a1
1 /*
2 * HID over I2C protocol implementation
3 *
4 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
5 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
6 * Copyright (c) 2012 Red Hat, Inc
7 *
8 * This code is partly based on "USB HID support for Linux":
9 *
10 * Copyright (c) 1999 Andreas Gal
11 * Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
12 * Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
13 * Copyright (c) 2007-2008 Oliver Neukum
14 * Copyright (c) 2006-2010 Jiri Kosina
15 *
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file COPYING in the main directory of this archive for
18 * more details.
19 */
20
21 #include <linux/module.h>
22 #include <linux/i2c.h>
23 #include <linux/interrupt.h>
24 #include <linux/input.h>
25 #include <linux/irq.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/pm.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/device.h>
31 #include <linux/wait.h>
32 #include <linux/err.h>
33 #include <linux/string.h>
34 #include <linux/list.h>
35 #include <linux/jiffies.h>
36 #include <linux/kernel.h>
37 #include <linux/hid.h>
38 #include <linux/mutex.h>
39 #include <linux/acpi.h>
40 #include <linux/of.h>
41 #include <linux/regulator/consumer.h>
42
43 #include <linux/platform_data/i2c-hid.h>
44
45 #include "../hid-ids.h"
46
47 /* quirks to control the device */
48 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV BIT(0)
49
50 /* flags */
51 #define I2C_HID_STARTED 0
52 #define I2C_HID_RESET_PENDING 1
53 #define I2C_HID_READ_PENDING 2
54
55 #define I2C_HID_PWR_ON 0x00
56 #define I2C_HID_PWR_SLEEP 0x01
57
58 /* debug option */
59 static bool debug;
60 module_param(debug, bool, 0444);
61 MODULE_PARM_DESC(debug, "print a lot of debug information");
62
63 #define i2c_hid_dbg(ihid, fmt, arg...) \
64 do { \
65 if (debug) \
66 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
67 } while (0)
68
69 struct i2c_hid_desc {
70 __le16 wHIDDescLength;
71 __le16 bcdVersion;
72 __le16 wReportDescLength;
73 __le16 wReportDescRegister;
74 __le16 wInputRegister;
75 __le16 wMaxInputLength;
76 __le16 wOutputRegister;
77 __le16 wMaxOutputLength;
78 __le16 wCommandRegister;
79 __le16 wDataRegister;
80 __le16 wVendorID;
81 __le16 wProductID;
82 __le16 wVersionID;
83 __le32 reserved;
84 } __packed;
85
86 struct i2c_hid_cmd {
87 unsigned int registerIndex;
88 __u8 opcode;
89 unsigned int length;
90 bool wait;
91 };
92
93 union command {
94 u8 data[0];
95 struct cmd {
96 __le16 reg;
97 __u8 reportTypeID;
98 __u8 opcode;
99 } __packed c;
100 };
101
102 #define I2C_HID_CMD(opcode_) \
103 .opcode = opcode_, .length = 4, \
104 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
105
106 /* fetch HID descriptor */
107 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
108 /* fetch report descriptors */
109 static const struct i2c_hid_cmd hid_report_descr_cmd = {
110 .registerIndex = offsetof(struct i2c_hid_desc,
111 wReportDescRegister),
112 .opcode = 0x00,
113 .length = 2 };
114 /* commands */
115 static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01),
116 .wait = true };
117 static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) };
118 static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) };
119 static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) };
120 static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 };
121
122 /*
123 * These definitions are not used here, but are defined by the spec.
124 * Keeping them here for documentation purposes.
125 *
126 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
127 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
128 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
129 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
130 */
131
132 static DEFINE_MUTEX(i2c_hid_open_mut);
133
134 /* The main device structure */
135 struct i2c_hid {
136 struct i2c_client *client; /* i2c client */
137 struct hid_device *hid; /* pointer to corresponding HID dev */
138 union {
139 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
140 struct i2c_hid_desc hdesc; /* the HID Descriptor */
141 };
142 __le16 wHIDDescRegister; /* location of the i2c
143 * register of the HID
144 * descriptor. */
145 unsigned int bufsize; /* i2c buffer size */
146 char *inbuf; /* Input buffer */
147 char *rawbuf; /* Raw Input buffer */
148 char *cmdbuf; /* Command buffer */
149 char *argsbuf; /* Command arguments buffer */
150
151 unsigned long flags; /* device flags */
152 unsigned long quirks; /* Various quirks */
153
154 wait_queue_head_t wait; /* For waiting the interrupt */
155
156 struct i2c_hid_platform_data pdata;
157
158 bool irq_wake_enabled;
159 struct mutex reset_lock;
160 };
161
162 static const struct i2c_hid_quirks {
163 __u16 idVendor;
164 __u16 idProduct;
165 __u32 quirks;
166 } i2c_hid_quirks[] = {
167 { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8752,
168 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
169 { USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8755,
170 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
171 { 0, 0 }
172 };
173
174 /*
175 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
176 * @idVendor: the 16-bit vendor ID
177 * @idProduct: the 16-bit product ID
178 *
179 * Returns: a u32 quirks value.
180 */
181 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
182 {
183 u32 quirks = 0;
184 int n;
185
186 for (n = 0; i2c_hid_quirks[n].idVendor; n++)
187 if (i2c_hid_quirks[n].idVendor == idVendor &&
188 (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
189 i2c_hid_quirks[n].idProduct == idProduct))
190 quirks = i2c_hid_quirks[n].quirks;
191
192 return quirks;
193 }
194
195 static int __i2c_hid_command(struct i2c_client *client,
196 const struct i2c_hid_cmd *command, u8 reportID,
197 u8 reportType, u8 *args, int args_len,
198 unsigned char *buf_recv, int data_len)
199 {
200 struct i2c_hid *ihid = i2c_get_clientdata(client);
201 union command *cmd = (union command *)ihid->cmdbuf;
202 int ret;
203 struct i2c_msg msg[2];
204 int msg_num = 1;
205
206 int length = command->length;
207 bool wait = command->wait;
208 unsigned int registerIndex = command->registerIndex;
209
210 /* special case for hid_descr_cmd */
211 if (command == &hid_descr_cmd) {
212 cmd->c.reg = ihid->wHIDDescRegister;
213 } else {
214 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
215 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
216 }
217
218 if (length > 2) {
219 cmd->c.opcode = command->opcode;
220 cmd->c.reportTypeID = reportID | reportType << 4;
221 }
222
223 memcpy(cmd->data + length, args, args_len);
224 length += args_len;
225
226 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
227
228 msg[0].addr = client->addr;
229 msg[0].flags = client->flags & I2C_M_TEN;
230 msg[0].len = length;
231 msg[0].buf = cmd->data;
232 if (data_len > 0) {
233 msg[1].addr = client->addr;
234 msg[1].flags = client->flags & I2C_M_TEN;
235 msg[1].flags |= I2C_M_RD;
236 msg[1].len = data_len;
237 msg[1].buf = buf_recv;
238 msg_num = 2;
239 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
240 }
241
242 if (wait)
243 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
244
245 ret = i2c_transfer(client->adapter, msg, msg_num);
246
247 if (data_len > 0)
248 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
249
250 if (ret != msg_num)
251 return ret < 0 ? ret : -EIO;
252
253 ret = 0;
254
255 if (wait) {
256 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
257 if (!wait_event_timeout(ihid->wait,
258 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
259 msecs_to_jiffies(5000)))
260 ret = -ENODATA;
261 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
262 }
263
264 return ret;
265 }
266
267 static int i2c_hid_command(struct i2c_client *client,
268 const struct i2c_hid_cmd *command,
269 unsigned char *buf_recv, int data_len)
270 {
271 return __i2c_hid_command(client, command, 0, 0, NULL, 0,
272 buf_recv, data_len);
273 }
274
275 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
276 u8 reportID, unsigned char *buf_recv, int data_len)
277 {
278 struct i2c_hid *ihid = i2c_get_clientdata(client);
279 u8 args[3];
280 int ret;
281 int args_len = 0;
282 u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
283
284 i2c_hid_dbg(ihid, "%s\n", __func__);
285
286 if (reportID >= 0x0F) {
287 args[args_len++] = reportID;
288 reportID = 0x0F;
289 }
290
291 args[args_len++] = readRegister & 0xFF;
292 args[args_len++] = readRegister >> 8;
293
294 ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
295 reportType, args, args_len, buf_recv, data_len);
296 if (ret) {
297 dev_err(&client->dev,
298 "failed to retrieve report from device.\n");
299 return ret;
300 }
301
302 return 0;
303 }
304
305 /**
306 * i2c_hid_set_or_send_report: forward an incoming report to the device
307 * @client: the i2c_client of the device
308 * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
309 * @reportID: the report ID
310 * @buf: the actual data to transfer, without the report ID
311 * @len: size of buf
312 * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
313 */
314 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
315 u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
316 {
317 struct i2c_hid *ihid = i2c_get_clientdata(client);
318 u8 *args = ihid->argsbuf;
319 const struct i2c_hid_cmd *hidcmd;
320 int ret;
321 u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
322 u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
323 u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
324 u16 size;
325 int args_len;
326 int index = 0;
327
328 i2c_hid_dbg(ihid, "%s\n", __func__);
329
330 if (data_len > ihid->bufsize)
331 return -EINVAL;
332
333 size = 2 /* size */ +
334 (reportID ? 1 : 0) /* reportID */ +
335 data_len /* buf */;
336 args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
337 2 /* dataRegister */ +
338 size /* args */;
339
340 if (!use_data && maxOutputLength == 0)
341 return -ENOSYS;
342
343 if (reportID >= 0x0F) {
344 args[index++] = reportID;
345 reportID = 0x0F;
346 }
347
348 /*
349 * use the data register for feature reports or if the device does not
350 * support the output register
351 */
352 if (use_data) {
353 args[index++] = dataRegister & 0xFF;
354 args[index++] = dataRegister >> 8;
355 hidcmd = &hid_set_report_cmd;
356 } else {
357 args[index++] = outputRegister & 0xFF;
358 args[index++] = outputRegister >> 8;
359 hidcmd = &hid_no_cmd;
360 }
361
362 args[index++] = size & 0xFF;
363 args[index++] = size >> 8;
364
365 if (reportID)
366 args[index++] = reportID;
367
368 memcpy(&args[index], buf, data_len);
369
370 ret = __i2c_hid_command(client, hidcmd, reportID,
371 reportType, args, args_len, NULL, 0);
372 if (ret) {
373 dev_err(&client->dev, "failed to set a report to device.\n");
374 return ret;
375 }
376
377 return data_len;
378 }
379
380 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
381 {
382 struct i2c_hid *ihid = i2c_get_clientdata(client);
383 int ret;
384
385 i2c_hid_dbg(ihid, "%s\n", __func__);
386
387 /*
388 * Some devices require to send a command to wakeup before power on.
389 * The call will get a return value (EREMOTEIO) but device will be
390 * triggered and activated. After that, it goes like a normal device.
391 */
392 if (power_state == I2C_HID_PWR_ON &&
393 ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) {
394 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0);
395
396 /* Device was already activated */
397 if (!ret)
398 goto set_pwr_exit;
399 }
400
401 ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
402 0, NULL, 0, NULL, 0);
403
404 if (ret)
405 dev_err(&client->dev, "failed to change power setting.\n");
406
407 set_pwr_exit:
408 return ret;
409 }
410
411 static int i2c_hid_hwreset(struct i2c_client *client)
412 {
413 struct i2c_hid *ihid = i2c_get_clientdata(client);
414 int ret;
415
416 i2c_hid_dbg(ihid, "%s\n", __func__);
417
418 /*
419 * This prevents sending feature reports while the device is
420 * being reset. Otherwise we may lose the reset complete
421 * interrupt.
422 */
423 mutex_lock(&ihid->reset_lock);
424
425 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
426 if (ret)
427 goto out_unlock;
428
429 /*
430 * The HID over I2C specification states that if a DEVICE needs time
431 * after the PWR_ON request, it should utilise CLOCK stretching.
432 * However, it has been observered that the Windows driver provides a
433 * 1ms sleep between the PWR_ON and RESET requests and that some devices
434 * rely on this.
435 */
436 usleep_range(1000, 5000);
437
438 i2c_hid_dbg(ihid, "resetting...\n");
439
440 ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
441 if (ret) {
442 dev_err(&client->dev, "failed to reset device.\n");
443 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
444 }
445
446 out_unlock:
447 mutex_unlock(&ihid->reset_lock);
448 return ret;
449 }
450
451 static void i2c_hid_get_input(struct i2c_hid *ihid)
452 {
453 int ret, ret_size;
454 int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
455
456 if (size > ihid->bufsize)
457 size = ihid->bufsize;
458
459 ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
460 if (ret != size) {
461 if (ret < 0)
462 return;
463
464 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
465 __func__, ret, size);
466 return;
467 }
468
469 ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
470
471 if (!ret_size) {
472 /* host or device initiated RESET completed */
473 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
474 wake_up(&ihid->wait);
475 return;
476 }
477
478 if (ret_size > size) {
479 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
480 __func__, size, ret_size);
481 return;
482 }
483
484 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
485
486 if (test_bit(I2C_HID_STARTED, &ihid->flags))
487 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
488 ret_size - 2, 1);
489
490 return;
491 }
492
493 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
494 {
495 struct i2c_hid *ihid = dev_id;
496
497 if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
498 return IRQ_HANDLED;
499
500 i2c_hid_get_input(ihid);
501
502 return IRQ_HANDLED;
503 }
504
505 static int i2c_hid_get_report_length(struct hid_report *report)
506 {
507 return ((report->size - 1) >> 3) + 1 +
508 report->device->report_enum[report->type].numbered + 2;
509 }
510
511 /*
512 * Traverse the supplied list of reports and find the longest
513 */
514 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
515 unsigned int *max)
516 {
517 struct hid_report *report;
518 unsigned int size;
519
520 /* We should not rely on wMaxInputLength, as some devices may set it to
521 * a wrong length. */
522 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
523 size = i2c_hid_get_report_length(report);
524 if (*max < size)
525 *max = size;
526 }
527 }
528
529 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
530 {
531 kfree(ihid->inbuf);
532 kfree(ihid->rawbuf);
533 kfree(ihid->argsbuf);
534 kfree(ihid->cmdbuf);
535 ihid->inbuf = NULL;
536 ihid->rawbuf = NULL;
537 ihid->cmdbuf = NULL;
538 ihid->argsbuf = NULL;
539 ihid->bufsize = 0;
540 }
541
542 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
543 {
544 /* the worst case is computed from the set_report command with a
545 * reportID > 15 and the maximum report length */
546 int args_len = sizeof(__u8) + /* optional ReportID byte */
547 sizeof(__u16) + /* data register */
548 sizeof(__u16) + /* size of the report */
549 report_size; /* report */
550
551 ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
552 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
553 ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
554 ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
555
556 if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
557 i2c_hid_free_buffers(ihid);
558 return -ENOMEM;
559 }
560
561 ihid->bufsize = report_size;
562
563 return 0;
564 }
565
566 static int i2c_hid_get_raw_report(struct hid_device *hid,
567 unsigned char report_number, __u8 *buf, size_t count,
568 unsigned char report_type)
569 {
570 struct i2c_client *client = hid->driver_data;
571 struct i2c_hid *ihid = i2c_get_clientdata(client);
572 size_t ret_count, ask_count;
573 int ret;
574
575 if (report_type == HID_OUTPUT_REPORT)
576 return -EINVAL;
577
578 /* +2 bytes to include the size of the reply in the query buffer */
579 ask_count = min(count + 2, (size_t)ihid->bufsize);
580
581 ret = i2c_hid_get_report(client,
582 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
583 report_number, ihid->rawbuf, ask_count);
584
585 if (ret < 0)
586 return ret;
587
588 ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
589
590 if (ret_count <= 2)
591 return 0;
592
593 ret_count = min(ret_count, ask_count);
594
595 /* The query buffer contains the size, dropping it in the reply */
596 count = min(count, ret_count - 2);
597 memcpy(buf, ihid->rawbuf + 2, count);
598
599 return count;
600 }
601
602 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
603 size_t count, unsigned char report_type, bool use_data)
604 {
605 struct i2c_client *client = hid->driver_data;
606 struct i2c_hid *ihid = i2c_get_clientdata(client);
607 int report_id = buf[0];
608 int ret;
609
610 if (report_type == HID_INPUT_REPORT)
611 return -EINVAL;
612
613 mutex_lock(&ihid->reset_lock);
614
615 if (report_id) {
616 buf++;
617 count--;
618 }
619
620 ret = i2c_hid_set_or_send_report(client,
621 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
622 report_id, buf, count, use_data);
623
624 if (report_id && ret >= 0)
625 ret++; /* add report_id to the number of transfered bytes */
626
627 mutex_unlock(&ihid->reset_lock);
628
629 return ret;
630 }
631
632 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
633 size_t count)
634 {
635 return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
636 false);
637 }
638
639 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
640 __u8 *buf, size_t len, unsigned char rtype,
641 int reqtype)
642 {
643 switch (reqtype) {
644 case HID_REQ_GET_REPORT:
645 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
646 case HID_REQ_SET_REPORT:
647 if (buf[0] != reportnum)
648 return -EINVAL;
649 return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
650 default:
651 return -EIO;
652 }
653 }
654
655 static int i2c_hid_parse(struct hid_device *hid)
656 {
657 struct i2c_client *client = hid->driver_data;
658 struct i2c_hid *ihid = i2c_get_clientdata(client);
659 struct i2c_hid_desc *hdesc = &ihid->hdesc;
660 unsigned int rsize;
661 char *rdesc;
662 int ret;
663 int tries = 3;
664
665 i2c_hid_dbg(ihid, "entering %s\n", __func__);
666
667 rsize = le16_to_cpu(hdesc->wReportDescLength);
668 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
669 dbg_hid("weird size of report descriptor (%u)\n", rsize);
670 return -EINVAL;
671 }
672
673 do {
674 ret = i2c_hid_hwreset(client);
675 if (ret)
676 msleep(1000);
677 } while (tries-- > 0 && ret);
678
679 if (ret)
680 return ret;
681
682 rdesc = kzalloc(rsize, GFP_KERNEL);
683
684 if (!rdesc) {
685 dbg_hid("couldn't allocate rdesc memory\n");
686 return -ENOMEM;
687 }
688
689 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
690
691 ret = i2c_hid_command(client, &hid_report_descr_cmd, rdesc, rsize);
692 if (ret) {
693 hid_err(hid, "reading report descriptor failed\n");
694 kfree(rdesc);
695 return -EIO;
696 }
697
698 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
699
700 ret = hid_parse_report(hid, rdesc, rsize);
701 kfree(rdesc);
702 if (ret) {
703 dbg_hid("parsing report descriptor failed\n");
704 return ret;
705 }
706
707 return 0;
708 }
709
710 static int i2c_hid_start(struct hid_device *hid)
711 {
712 struct i2c_client *client = hid->driver_data;
713 struct i2c_hid *ihid = i2c_get_clientdata(client);
714 int ret;
715 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
716
717 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
718 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
719 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
720
721 if (bufsize > ihid->bufsize) {
722 disable_irq(client->irq);
723 i2c_hid_free_buffers(ihid);
724
725 ret = i2c_hid_alloc_buffers(ihid, bufsize);
726 enable_irq(client->irq);
727
728 if (ret)
729 return ret;
730 }
731
732 return 0;
733 }
734
735 static void i2c_hid_stop(struct hid_device *hid)
736 {
737 hid->claimed = 0;
738 }
739
740 static int i2c_hid_open(struct hid_device *hid)
741 {
742 struct i2c_client *client = hid->driver_data;
743 struct i2c_hid *ihid = i2c_get_clientdata(client);
744 int ret = 0;
745
746 ret = pm_runtime_get_sync(&client->dev);
747 if (ret < 0)
748 return ret;
749
750 set_bit(I2C_HID_STARTED, &ihid->flags);
751 return 0;
752 }
753
754 static void i2c_hid_close(struct hid_device *hid)
755 {
756 struct i2c_client *client = hid->driver_data;
757 struct i2c_hid *ihid = i2c_get_clientdata(client);
758
759 clear_bit(I2C_HID_STARTED, &ihid->flags);
760
761 /* Save some power */
762 pm_runtime_put(&client->dev);
763 }
764
765 static int i2c_hid_power(struct hid_device *hid, int lvl)
766 {
767 struct i2c_client *client = hid->driver_data;
768 struct i2c_hid *ihid = i2c_get_clientdata(client);
769
770 i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
771
772 switch (lvl) {
773 case PM_HINT_FULLON:
774 pm_runtime_get_sync(&client->dev);
775 break;
776 case PM_HINT_NORMAL:
777 pm_runtime_put(&client->dev);
778 break;
779 }
780 return 0;
781 }
782
783 struct hid_ll_driver i2c_hid_ll_driver = {
784 .parse = i2c_hid_parse,
785 .start = i2c_hid_start,
786 .stop = i2c_hid_stop,
787 .open = i2c_hid_open,
788 .close = i2c_hid_close,
789 .power = i2c_hid_power,
790 .output_report = i2c_hid_output_report,
791 .raw_request = i2c_hid_raw_request,
792 };
793 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
794
795 static int i2c_hid_init_irq(struct i2c_client *client)
796 {
797 struct i2c_hid *ihid = i2c_get_clientdata(client);
798 unsigned long irqflags = 0;
799 int ret;
800
801 dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
802
803 if (!irq_get_trigger_type(client->irq))
804 irqflags = IRQF_TRIGGER_LOW;
805
806 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
807 irqflags | IRQF_ONESHOT, client->name, ihid);
808 if (ret < 0) {
809 dev_warn(&client->dev,
810 "Could not register for %s interrupt, irq = %d,"
811 " ret = %d\n",
812 client->name, client->irq, ret);
813
814 return ret;
815 }
816
817 return 0;
818 }
819
820 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
821 {
822 struct i2c_client *client = ihid->client;
823 struct i2c_hid_desc *hdesc = &ihid->hdesc;
824 unsigned int dsize;
825 int ret;
826
827 /* i2c hid fetch using a fixed descriptor size (30 bytes) */
828 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
829 ret = i2c_hid_command(client, &hid_descr_cmd, ihid->hdesc_buffer,
830 sizeof(struct i2c_hid_desc));
831 if (ret) {
832 dev_err(&client->dev, "hid_descr_cmd failed\n");
833 return -ENODEV;
834 }
835
836 /* Validate the length of HID descriptor, the 4 first bytes:
837 * bytes 0-1 -> length
838 * bytes 2-3 -> bcdVersion (has to be 1.00) */
839 /* check bcdVersion == 1.0 */
840 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
841 dev_err(&client->dev,
842 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
843 le16_to_cpu(hdesc->bcdVersion));
844 return -ENODEV;
845 }
846
847 /* Descriptor length should be 30 bytes as per the specification */
848 dsize = le16_to_cpu(hdesc->wHIDDescLength);
849 if (dsize != sizeof(struct i2c_hid_desc)) {
850 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
851 dsize);
852 return -ENODEV;
853 }
854 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
855 return 0;
856 }
857
858 #ifdef CONFIG_ACPI
859 static int i2c_hid_acpi_pdata(struct i2c_client *client,
860 struct i2c_hid_platform_data *pdata)
861 {
862 static guid_t i2c_hid_guid =
863 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
864 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
865 union acpi_object *obj;
866 struct acpi_device *adev;
867 acpi_handle handle;
868
869 handle = ACPI_HANDLE(&client->dev);
870 if (!handle || acpi_bus_get_device(handle, &adev))
871 return -ENODEV;
872
873 obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
874 ACPI_TYPE_INTEGER);
875 if (!obj) {
876 dev_err(&client->dev, "device _DSM execution failed\n");
877 return -ENODEV;
878 }
879
880 pdata->hid_descriptor_address = obj->integer.value;
881 ACPI_FREE(obj);
882
883 return 0;
884 }
885
886 static void i2c_hid_acpi_fix_up_power(struct device *dev)
887 {
888 acpi_handle handle = ACPI_HANDLE(dev);
889 struct acpi_device *adev;
890
891 if (handle && acpi_bus_get_device(handle, &adev) == 0)
892 acpi_device_fix_up_power(adev);
893 }
894
895 static const struct acpi_device_id i2c_hid_acpi_match[] = {
896 {"ACPI0C50", 0 },
897 {"PNP0C50", 0 },
898 { },
899 };
900 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
901 #else
902 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
903 struct i2c_hid_platform_data *pdata)
904 {
905 return -ENODEV;
906 }
907
908 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {}
909 #endif
910
911 #ifdef CONFIG_OF
912 static int i2c_hid_of_probe(struct i2c_client *client,
913 struct i2c_hid_platform_data *pdata)
914 {
915 struct device *dev = &client->dev;
916 u32 val;
917 int ret;
918
919 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
920 if (ret) {
921 dev_err(&client->dev, "HID register address not provided\n");
922 return -ENODEV;
923 }
924 if (val >> 16) {
925 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
926 val);
927 return -EINVAL;
928 }
929 pdata->hid_descriptor_address = val;
930
931 ret = of_property_read_u32(dev->of_node, "post-power-on-delay-ms",
932 &val);
933 if (!ret)
934 pdata->post_power_delay_ms = val;
935
936 return 0;
937 }
938
939 static const struct of_device_id i2c_hid_of_match[] = {
940 { .compatible = "hid-over-i2c" },
941 {},
942 };
943 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
944 #else
945 static inline int i2c_hid_of_probe(struct i2c_client *client,
946 struct i2c_hid_platform_data *pdata)
947 {
948 return -ENODEV;
949 }
950 #endif
951
952 static int i2c_hid_probe(struct i2c_client *client,
953 const struct i2c_device_id *dev_id)
954 {
955 int ret;
956 struct i2c_hid *ihid;
957 struct hid_device *hid;
958 __u16 hidRegister;
959 struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
960
961 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
962
963 if (!client->irq) {
964 dev_err(&client->dev,
965 "HID over i2c has not been provided an Int IRQ\n");
966 return -EINVAL;
967 }
968
969 if (client->irq < 0) {
970 if (client->irq != -EPROBE_DEFER)
971 dev_err(&client->dev,
972 "HID over i2c doesn't have a valid IRQ\n");
973 return client->irq;
974 }
975
976 ihid = kzalloc(sizeof(struct i2c_hid), GFP_KERNEL);
977 if (!ihid)
978 return -ENOMEM;
979
980 if (client->dev.of_node) {
981 ret = i2c_hid_of_probe(client, &ihid->pdata);
982 if (ret)
983 goto err;
984 } else if (!platform_data) {
985 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
986 if (ret) {
987 dev_err(&client->dev,
988 "HID register address not provided\n");
989 goto err;
990 }
991 } else {
992 ihid->pdata = *platform_data;
993 }
994
995 ihid->pdata.supply = devm_regulator_get(&client->dev, "vdd");
996 if (IS_ERR(ihid->pdata.supply)) {
997 ret = PTR_ERR(ihid->pdata.supply);
998 if (ret != -EPROBE_DEFER)
999 dev_err(&client->dev, "Failed to get regulator: %d\n",
1000 ret);
1001 goto err;
1002 }
1003
1004 ret = regulator_enable(ihid->pdata.supply);
1005 if (ret < 0) {
1006 dev_err(&client->dev, "Failed to enable regulator: %d\n",
1007 ret);
1008 goto err;
1009 }
1010 if (ihid->pdata.post_power_delay_ms)
1011 msleep(ihid->pdata.post_power_delay_ms);
1012
1013 i2c_set_clientdata(client, ihid);
1014
1015 ihid->client = client;
1016
1017 hidRegister = ihid->pdata.hid_descriptor_address;
1018 ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
1019
1020 init_waitqueue_head(&ihid->wait);
1021 mutex_init(&ihid->reset_lock);
1022
1023 /* we need to allocate the command buffer without knowing the maximum
1024 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1025 * real computation later. */
1026 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1027 if (ret < 0)
1028 goto err_regulator;
1029
1030 i2c_hid_acpi_fix_up_power(&client->dev);
1031
1032 pm_runtime_get_noresume(&client->dev);
1033 pm_runtime_set_active(&client->dev);
1034 pm_runtime_enable(&client->dev);
1035 device_enable_async_suspend(&client->dev);
1036
1037 ret = i2c_hid_fetch_hid_descriptor(ihid);
1038 if (ret < 0)
1039 goto err_pm;
1040
1041 ret = i2c_hid_init_irq(client);
1042 if (ret < 0)
1043 goto err_pm;
1044
1045 hid = hid_allocate_device();
1046 if (IS_ERR(hid)) {
1047 ret = PTR_ERR(hid);
1048 goto err_irq;
1049 }
1050
1051 ihid->hid = hid;
1052
1053 hid->driver_data = client;
1054 hid->ll_driver = &i2c_hid_ll_driver;
1055 hid->dev.parent = &client->dev;
1056 hid->bus = BUS_I2C;
1057 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1058 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1059 hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1060
1061 snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX",
1062 client->name, hid->vendor, hid->product);
1063 strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1064
1065 ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1066
1067 ret = hid_add_device(hid);
1068 if (ret) {
1069 if (ret != -ENODEV)
1070 hid_err(client, "can't add hid device: %d\n", ret);
1071 goto err_mem_free;
1072 }
1073
1074 pm_runtime_put(&client->dev);
1075 return 0;
1076
1077 err_mem_free:
1078 hid_destroy_device(hid);
1079
1080 err_irq:
1081 free_irq(client->irq, ihid);
1082
1083 err_pm:
1084 pm_runtime_put_noidle(&client->dev);
1085 pm_runtime_disable(&client->dev);
1086
1087 err_regulator:
1088 regulator_disable(ihid->pdata.supply);
1089
1090 err:
1091 i2c_hid_free_buffers(ihid);
1092 kfree(ihid);
1093 return ret;
1094 }
1095
1096 static int i2c_hid_remove(struct i2c_client *client)
1097 {
1098 struct i2c_hid *ihid = i2c_get_clientdata(client);
1099 struct hid_device *hid;
1100
1101 pm_runtime_get_sync(&client->dev);
1102 pm_runtime_disable(&client->dev);
1103 pm_runtime_set_suspended(&client->dev);
1104 pm_runtime_put_noidle(&client->dev);
1105
1106 hid = ihid->hid;
1107 hid_destroy_device(hid);
1108
1109 free_irq(client->irq, ihid);
1110
1111 if (ihid->bufsize)
1112 i2c_hid_free_buffers(ihid);
1113
1114 regulator_disable(ihid->pdata.supply);
1115
1116 kfree(ihid);
1117
1118 return 0;
1119 }
1120
1121 static void i2c_hid_shutdown(struct i2c_client *client)
1122 {
1123 struct i2c_hid *ihid = i2c_get_clientdata(client);
1124
1125 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1126 free_irq(client->irq, ihid);
1127 }
1128
1129 #ifdef CONFIG_PM_SLEEP
1130 static int i2c_hid_suspend(struct device *dev)
1131 {
1132 struct i2c_client *client = to_i2c_client(dev);
1133 struct i2c_hid *ihid = i2c_get_clientdata(client);
1134 struct hid_device *hid = ihid->hid;
1135 int ret;
1136 int wake_status;
1137
1138 if (hid->driver && hid->driver->suspend) {
1139 /*
1140 * Wake up the device so that IO issues in
1141 * HID driver's suspend code can succeed.
1142 */
1143 ret = pm_runtime_resume(dev);
1144 if (ret < 0)
1145 return ret;
1146
1147 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1148 if (ret < 0)
1149 return ret;
1150 }
1151
1152 if (!pm_runtime_suspended(dev)) {
1153 /* Save some power */
1154 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1155
1156 disable_irq(client->irq);
1157 }
1158
1159 if (device_may_wakeup(&client->dev)) {
1160 wake_status = enable_irq_wake(client->irq);
1161 if (!wake_status)
1162 ihid->irq_wake_enabled = true;
1163 else
1164 hid_warn(hid, "Failed to enable irq wake: %d\n",
1165 wake_status);
1166 } else {
1167 ret = regulator_disable(ihid->pdata.supply);
1168 if (ret < 0)
1169 hid_warn(hid, "Failed to disable supply: %d\n", ret);
1170 }
1171
1172 return 0;
1173 }
1174
1175 static int i2c_hid_resume(struct device *dev)
1176 {
1177 int ret;
1178 struct i2c_client *client = to_i2c_client(dev);
1179 struct i2c_hid *ihid = i2c_get_clientdata(client);
1180 struct hid_device *hid = ihid->hid;
1181 int wake_status;
1182
1183 if (!device_may_wakeup(&client->dev)) {
1184 ret = regulator_enable(ihid->pdata.supply);
1185 if (ret < 0)
1186 hid_warn(hid, "Failed to enable supply: %d\n", ret);
1187 if (ihid->pdata.post_power_delay_ms)
1188 msleep(ihid->pdata.post_power_delay_ms);
1189 } else if (ihid->irq_wake_enabled) {
1190 wake_status = disable_irq_wake(client->irq);
1191 if (!wake_status)
1192 ihid->irq_wake_enabled = false;
1193 else
1194 hid_warn(hid, "Failed to disable irq wake: %d\n",
1195 wake_status);
1196 }
1197
1198 /* We'll resume to full power */
1199 pm_runtime_disable(dev);
1200 pm_runtime_set_active(dev);
1201 pm_runtime_enable(dev);
1202
1203 enable_irq(client->irq);
1204 ret = i2c_hid_hwreset(client);
1205 if (ret)
1206 return ret;
1207
1208 if (hid->driver && hid->driver->reset_resume) {
1209 ret = hid->driver->reset_resume(hid);
1210 return ret;
1211 }
1212
1213 return 0;
1214 }
1215 #endif
1216
1217 #ifdef CONFIG_PM
1218 static int i2c_hid_runtime_suspend(struct device *dev)
1219 {
1220 struct i2c_client *client = to_i2c_client(dev);
1221
1222 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1223 disable_irq(client->irq);
1224 return 0;
1225 }
1226
1227 static int i2c_hid_runtime_resume(struct device *dev)
1228 {
1229 struct i2c_client *client = to_i2c_client(dev);
1230
1231 enable_irq(client->irq);
1232 i2c_hid_set_power(client, I2C_HID_PWR_ON);
1233 return 0;
1234 }
1235 #endif
1236
1237 static const struct dev_pm_ops i2c_hid_pm = {
1238 SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1239 SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume,
1240 NULL)
1241 };
1242
1243 static const struct i2c_device_id i2c_hid_id_table[] = {
1244 { "hid", 0 },
1245 { "hid-over-i2c", 0 },
1246 { },
1247 };
1248 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1249
1250
1251 static struct i2c_driver i2c_hid_driver = {
1252 .driver = {
1253 .name = "i2c_hid",
1254 .pm = &i2c_hid_pm,
1255 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1256 .of_match_table = of_match_ptr(i2c_hid_of_match),
1257 },
1258
1259 .probe = i2c_hid_probe,
1260 .remove = i2c_hid_remove,
1261 .shutdown = i2c_hid_shutdown,
1262 .id_table = i2c_hid_id_table,
1263 };
1264
1265 module_i2c_driver(i2c_hid_driver);
1266
1267 MODULE_DESCRIPTION("HID over I2C core driver");
1268 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1269 MODULE_LICENSE("GPL");
Linux with added FPC-III support