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treewide: remove redundant IS_ERR() before error code check
[linux/fpc-iii.git] / drivers / hid / i2c-hid / i2c-hid-core.c
blob009000c5d55cddfaad101f1b33d5b37497e0f176
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/device.h>
30 #include <linux/wait.h>
31 #include <linux/err.h>
32 #include <linux/string.h>
33 #include <linux/list.h>
34 #include <linux/jiffies.h>
35 #include <linux/kernel.h>
36 #include <linux/hid.h>
37 #include <linux/mutex.h>
38 #include <linux/acpi.h>
39 #include <linux/of.h>
40 #include <linux/regulator/consumer.h>
41
42 #include <linux/platform_data/i2c-hid.h>
43
44 #include "../hid-ids.h"
45 #include "i2c-hid.h"
46
47 /* quirks to control the device */
48 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV BIT(0)
49 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(1)
50 #define I2C_HID_QUIRK_BOGUS_IRQ BIT(4)
51 #define I2C_HID_QUIRK_RESET_ON_RESUME BIT(5)
52 #define I2C_HID_QUIRK_BAD_INPUT_SIZE BIT(6)
53
54
55 /* flags */
56 #define I2C_HID_STARTED 0
57 #define I2C_HID_RESET_PENDING 1
58 #define I2C_HID_READ_PENDING 2
59
60 #define I2C_HID_PWR_ON 0x00
61 #define I2C_HID_PWR_SLEEP 0x01
62
63 /* debug option */
64 static bool debug;
65 module_param(debug, bool, 0444);
66 MODULE_PARM_DESC(debug, "print a lot of debug information");
67
68 #define i2c_hid_dbg(ihid, fmt, arg...) \
69 do { \
70 if (debug) \
71 dev_printk(KERN_DEBUG, &(ihid)->client->dev, fmt, ##arg); \
72 } while (0)
73
74 struct i2c_hid_desc {
75 __le16 wHIDDescLength;
76 __le16 bcdVersion;
77 __le16 wReportDescLength;
78 __le16 wReportDescRegister;
79 __le16 wInputRegister;
80 __le16 wMaxInputLength;
81 __le16 wOutputRegister;
82 __le16 wMaxOutputLength;
83 __le16 wCommandRegister;
84 __le16 wDataRegister;
85 __le16 wVendorID;
86 __le16 wProductID;
87 __le16 wVersionID;
88 __le32 reserved;
89 } __packed;
90
91 struct i2c_hid_cmd {
92 unsigned int registerIndex;
93 __u8 opcode;
94 unsigned int length;
95 bool wait;
96 };
97
98 union command {
99 u8 data[0];
100 struct cmd {
101 __le16 reg;
102 __u8 reportTypeID;
103 __u8 opcode;
104 } __packed c;
105 };
106
107 #define I2C_HID_CMD(opcode_) \
108 .opcode = opcode_, .length = 4, \
109 .registerIndex = offsetof(struct i2c_hid_desc, wCommandRegister)
110
111 /* fetch HID descriptor */
112 static const struct i2c_hid_cmd hid_descr_cmd = { .length = 2 };
113 /* fetch report descriptors */
114 static const struct i2c_hid_cmd hid_report_descr_cmd = {
115 .registerIndex = offsetof(struct i2c_hid_desc,
116 wReportDescRegister),
117 .opcode = 0x00,
118 .length = 2 };
119 /* commands */
120 static const struct i2c_hid_cmd hid_reset_cmd = { I2C_HID_CMD(0x01),
121 .wait = true };
122 static const struct i2c_hid_cmd hid_get_report_cmd = { I2C_HID_CMD(0x02) };
123 static const struct i2c_hid_cmd hid_set_report_cmd = { I2C_HID_CMD(0x03) };
124 static const struct i2c_hid_cmd hid_set_power_cmd = { I2C_HID_CMD(0x08) };
125 static const struct i2c_hid_cmd hid_no_cmd = { .length = 0 };
126
127 /*
128 * These definitions are not used here, but are defined by the spec.
129 * Keeping them here for documentation purposes.
130 *
131 * static const struct i2c_hid_cmd hid_get_idle_cmd = { I2C_HID_CMD(0x04) };
132 * static const struct i2c_hid_cmd hid_set_idle_cmd = { I2C_HID_CMD(0x05) };
133 * static const struct i2c_hid_cmd hid_get_protocol_cmd = { I2C_HID_CMD(0x06) };
134 * static const struct i2c_hid_cmd hid_set_protocol_cmd = { I2C_HID_CMD(0x07) };
135 */
136
137 /* The main device structure */
138 struct i2c_hid {
139 struct i2c_client *client; /* i2c client */
140 struct hid_device *hid; /* pointer to corresponding HID dev */
141 union {
142 __u8 hdesc_buffer[sizeof(struct i2c_hid_desc)];
143 struct i2c_hid_desc hdesc; /* the HID Descriptor */
144 };
145 __le16 wHIDDescRegister; /* location of the i2c
146 * register of the HID
147 * descriptor. */
148 unsigned int bufsize; /* i2c buffer size */
149 u8 *inbuf; /* Input buffer */
150 u8 *rawbuf; /* Raw Input buffer */
151 u8 *cmdbuf; /* Command buffer */
152 u8 *argsbuf; /* Command arguments buffer */
153
154 unsigned long flags; /* device flags */
155 unsigned long quirks; /* Various quirks */
156
157 wait_queue_head_t wait; /* For waiting the interrupt */
158
159 struct i2c_hid_platform_data pdata;
160
161 bool irq_wake_enabled;
162 struct mutex reset_lock;
163 };
164
165 static const struct i2c_hid_quirks {
166 __u16 idVendor;
167 __u16 idProduct;
168 __u32 quirks;
169 } i2c_hid_quirks[] = {
170 { USB_VENDOR_ID_WEIDA, HID_ANY_ID,
171 I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
172 { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
173 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
174 { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_3118,
175 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
176 { USB_VENDOR_ID_ELAN, HID_ANY_ID,
177 I2C_HID_QUIRK_BOGUS_IRQ },
178 { USB_VENDOR_ID_ALPS_JP, HID_ANY_ID,
179 I2C_HID_QUIRK_RESET_ON_RESUME },
180 { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
181 I2C_HID_QUIRK_BAD_INPUT_SIZE },
182 { 0, 0 }
183 };
184
185 /*
186 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
187 * @idVendor: the 16-bit vendor ID
188 * @idProduct: the 16-bit product ID
189 *
190 * Returns: a u32 quirks value.
191 */
192 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
193 {
194 u32 quirks = 0;
195 int n;
196
197 for (n = 0; i2c_hid_quirks[n].idVendor; n++)
198 if (i2c_hid_quirks[n].idVendor == idVendor &&
199 (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
200 i2c_hid_quirks[n].idProduct == idProduct))
201 quirks = i2c_hid_quirks[n].quirks;
202
203 return quirks;
204 }
205
206 static int __i2c_hid_command(struct i2c_client *client,
207 const struct i2c_hid_cmd *command, u8 reportID,
208 u8 reportType, u8 *args, int args_len,
209 unsigned char *buf_recv, int data_len)
210 {
211 struct i2c_hid *ihid = i2c_get_clientdata(client);
212 union command *cmd = (union command *)ihid->cmdbuf;
213 int ret;
214 struct i2c_msg msg[2];
215 int msg_num = 1;
216
217 int length = command->length;
218 bool wait = command->wait;
219 unsigned int registerIndex = command->registerIndex;
220
221 /* special case for hid_descr_cmd */
222 if (command == &hid_descr_cmd) {
223 cmd->c.reg = ihid->wHIDDescRegister;
224 } else {
225 cmd->data[0] = ihid->hdesc_buffer[registerIndex];
226 cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
227 }
228
229 if (length > 2) {
230 cmd->c.opcode = command->opcode;
231 cmd->c.reportTypeID = reportID | reportType << 4;
232 }
233
234 memcpy(cmd->data + length, args, args_len);
235 length += args_len;
236
237 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
238
239 msg[0].addr = client->addr;
240 msg[0].flags = client->flags & I2C_M_TEN;
241 msg[0].len = length;
242 msg[0].buf = cmd->data;
243 if (data_len > 0) {
244 msg[1].addr = client->addr;
245 msg[1].flags = client->flags & I2C_M_TEN;
246 msg[1].flags |= I2C_M_RD;
247 msg[1].len = data_len;
248 msg[1].buf = buf_recv;
249 msg_num = 2;
250 set_bit(I2C_HID_READ_PENDING, &ihid->flags);
251 }
252
253 if (wait)
254 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
255
256 ret = i2c_transfer(client->adapter, msg, msg_num);
257
258 if (data_len > 0)
259 clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
260
261 if (ret != msg_num)
262 return ret < 0 ? ret : -EIO;
263
264 ret = 0;
265
266 if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) {
267 msleep(100);
268 } else if (wait) {
269 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
270 if (!wait_event_timeout(ihid->wait,
271 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
272 msecs_to_jiffies(5000)))
273 ret = -ENODATA;
274 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
275 }
276
277 return ret;
278 }
279
280 static int i2c_hid_command(struct i2c_client *client,
281 const struct i2c_hid_cmd *command,
282 unsigned char *buf_recv, int data_len)
283 {
284 return __i2c_hid_command(client, command, 0, 0, NULL, 0,
285 buf_recv, data_len);
286 }
287
288 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
289 u8 reportID, unsigned char *buf_recv, int data_len)
290 {
291 struct i2c_hid *ihid = i2c_get_clientdata(client);
292 u8 args[3];
293 int ret;
294 int args_len = 0;
295 u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
296
297 i2c_hid_dbg(ihid, "%s\n", __func__);
298
299 if (reportID >= 0x0F) {
300 args[args_len++] = reportID;
301 reportID = 0x0F;
302 }
303
304 args[args_len++] = readRegister & 0xFF;
305 args[args_len++] = readRegister >> 8;
306
307 ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
308 reportType, args, args_len, buf_recv, data_len);
309 if (ret) {
310 dev_err(&client->dev,
311 "failed to retrieve report from device.\n");
312 return ret;
313 }
314
315 return 0;
316 }
317
318 /**
319 * i2c_hid_set_or_send_report: forward an incoming report to the device
320 * @client: the i2c_client of the device
321 * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
322 * @reportID: the report ID
323 * @buf: the actual data to transfer, without the report ID
324 * @len: size of buf
325 * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
326 */
327 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
328 u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
329 {
330 struct i2c_hid *ihid = i2c_get_clientdata(client);
331 u8 *args = ihid->argsbuf;
332 const struct i2c_hid_cmd *hidcmd;
333 int ret;
334 u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
335 u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
336 u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
337 u16 size;
338 int args_len;
339 int index = 0;
340
341 i2c_hid_dbg(ihid, "%s\n", __func__);
342
343 if (data_len > ihid->bufsize)
344 return -EINVAL;
345
346 size = 2 /* size */ +
347 (reportID ? 1 : 0) /* reportID */ +
348 data_len /* buf */;
349 args_len = (reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
350 2 /* dataRegister */ +
351 size /* args */;
352
353 if (!use_data && maxOutputLength == 0)
354 return -ENOSYS;
355
356 if (reportID >= 0x0F) {
357 args[index++] = reportID;
358 reportID = 0x0F;
359 }
360
361 /*
362 * use the data register for feature reports or if the device does not
363 * support the output register
364 */
365 if (use_data) {
366 args[index++] = dataRegister & 0xFF;
367 args[index++] = dataRegister >> 8;
368 hidcmd = &hid_set_report_cmd;
369 } else {
370 args[index++] = outputRegister & 0xFF;
371 args[index++] = outputRegister >> 8;
372 hidcmd = &hid_no_cmd;
373 }
374
375 args[index++] = size & 0xFF;
376 args[index++] = size >> 8;
377
378 if (reportID)
379 args[index++] = reportID;
380
381 memcpy(&args[index], buf, data_len);
382
383 ret = __i2c_hid_command(client, hidcmd, reportID,
384 reportType, args, args_len, NULL, 0);
385 if (ret) {
386 dev_err(&client->dev, "failed to set a report to device.\n");
387 return ret;
388 }
389
390 return data_len;
391 }
392
393 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
394 {
395 struct i2c_hid *ihid = i2c_get_clientdata(client);
396 int ret;
397
398 i2c_hid_dbg(ihid, "%s\n", __func__);
399
400 /*
401 * Some devices require to send a command to wakeup before power on.
402 * The call will get a return value (EREMOTEIO) but device will be
403 * triggered and activated. After that, it goes like a normal device.
404 */
405 if (power_state == I2C_HID_PWR_ON &&
406 ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) {
407 ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0);
408
409 /* Device was already activated */
410 if (!ret)
411 goto set_pwr_exit;
412 }
413
414 ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
415 0, NULL, 0, NULL, 0);
416
417 if (ret)
418 dev_err(&client->dev, "failed to change power setting.\n");
419
420 set_pwr_exit:
421 return ret;
422 }
423
424 static int i2c_hid_hwreset(struct i2c_client *client)
425 {
426 struct i2c_hid *ihid = i2c_get_clientdata(client);
427 int ret;
428
429 i2c_hid_dbg(ihid, "%s\n", __func__);
430
431 /*
432 * This prevents sending feature reports while the device is
433 * being reset. Otherwise we may lose the reset complete
434 * interrupt.
435 */
436 mutex_lock(&ihid->reset_lock);
437
438 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
439 if (ret)
440 goto out_unlock;
441
442 /*
443 * The HID over I2C specification states that if a DEVICE needs time
444 * after the PWR_ON request, it should utilise CLOCK stretching.
445 * However, it has been observered that the Windows driver provides a
446 * 1ms sleep between the PWR_ON and RESET requests and that some devices
447 * rely on this.
448 */
449 usleep_range(1000, 5000);
450
451 i2c_hid_dbg(ihid, "resetting...\n");
452
453 ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
454 if (ret) {
455 dev_err(&client->dev, "failed to reset device.\n");
456 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
457 goto out_unlock;
458 }
459
460 /* At least some SIS devices need this after reset */
461 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
462
463 out_unlock:
464 mutex_unlock(&ihid->reset_lock);
465 return ret;
466 }
467
468 static void i2c_hid_get_input(struct i2c_hid *ihid)
469 {
470 int ret;
471 u32 ret_size;
472 int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
473
474 if (size > ihid->bufsize)
475 size = ihid->bufsize;
476
477 ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
478 if (ret != size) {
479 if (ret < 0)
480 return;
481
482 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
483 __func__, ret, size);
484 return;
485 }
486
487 ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
488
489 if (!ret_size) {
490 /* host or device initiated RESET completed */
491 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
492 wake_up(&ihid->wait);
493 return;
494 }
495
496 if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) {
497 dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but "
498 "there's no data\n", __func__);
499 return;
500 }
501
502 if ((ret_size > size) || (ret_size < 2)) {
503 if (ihid->quirks & I2C_HID_QUIRK_BAD_INPUT_SIZE) {
504 ihid->inbuf[0] = size & 0xff;
505 ihid->inbuf[1] = size >> 8;
506 ret_size = size;
507 } else {
508 dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
509 __func__, size, ret_size);
510 return;
511 }
512 }
513
514 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
515
516 if (test_bit(I2C_HID_STARTED, &ihid->flags))
517 hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
518 ret_size - 2, 1);
519
520 return;
521 }
522
523 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
524 {
525 struct i2c_hid *ihid = dev_id;
526
527 if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
528 return IRQ_HANDLED;
529
530 i2c_hid_get_input(ihid);
531
532 return IRQ_HANDLED;
533 }
534
535 static int i2c_hid_get_report_length(struct hid_report *report)
536 {
537 return ((report->size - 1) >> 3) + 1 +
538 report->device->report_enum[report->type].numbered + 2;
539 }
540
541 /*
542 * Traverse the supplied list of reports and find the longest
543 */
544 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
545 unsigned int *max)
546 {
547 struct hid_report *report;
548 unsigned int size;
549
550 /* We should not rely on wMaxInputLength, as some devices may set it to
551 * a wrong length. */
552 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
553 size = i2c_hid_get_report_length(report);
554 if (*max < size)
555 *max = size;
556 }
557 }
558
559 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
560 {
561 kfree(ihid->inbuf);
562 kfree(ihid->rawbuf);
563 kfree(ihid->argsbuf);
564 kfree(ihid->cmdbuf);
565 ihid->inbuf = NULL;
566 ihid->rawbuf = NULL;
567 ihid->cmdbuf = NULL;
568 ihid->argsbuf = NULL;
569 ihid->bufsize = 0;
570 }
571
572 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
573 {
574 /* the worst case is computed from the set_report command with a
575 * reportID > 15 and the maximum report length */
576 int args_len = sizeof(__u8) + /* ReportID */
577 sizeof(__u8) + /* optional ReportID byte */
578 sizeof(__u16) + /* data register */
579 sizeof(__u16) + /* size of the report */
580 report_size; /* report */
581
582 ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
583 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
584 ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
585 ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
586
587 if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
588 i2c_hid_free_buffers(ihid);
589 return -ENOMEM;
590 }
591
592 ihid->bufsize = report_size;
593
594 return 0;
595 }
596
597 static int i2c_hid_get_raw_report(struct hid_device *hid,
598 unsigned char report_number, __u8 *buf, size_t count,
599 unsigned char report_type)
600 {
601 struct i2c_client *client = hid->driver_data;
602 struct i2c_hid *ihid = i2c_get_clientdata(client);
603 size_t ret_count, ask_count;
604 int ret;
605
606 if (report_type == HID_OUTPUT_REPORT)
607 return -EINVAL;
608
609 /* +2 bytes to include the size of the reply in the query buffer */
610 ask_count = min(count + 2, (size_t)ihid->bufsize);
611
612 ret = i2c_hid_get_report(client,
613 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
614 report_number, ihid->rawbuf, ask_count);
615
616 if (ret < 0)
617 return ret;
618
619 ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
620
621 if (ret_count <= 2)
622 return 0;
623
624 ret_count = min(ret_count, ask_count);
625
626 /* The query buffer contains the size, dropping it in the reply */
627 count = min(count, ret_count - 2);
628 memcpy(buf, ihid->rawbuf + 2, count);
629
630 return count;
631 }
632
633 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
634 size_t count, unsigned char report_type, bool use_data)
635 {
636 struct i2c_client *client = hid->driver_data;
637 struct i2c_hid *ihid = i2c_get_clientdata(client);
638 int report_id = buf[0];
639 int ret;
640
641 if (report_type == HID_INPUT_REPORT)
642 return -EINVAL;
643
644 mutex_lock(&ihid->reset_lock);
645
646 if (report_id) {
647 buf++;
648 count--;
649 }
650
651 ret = i2c_hid_set_or_send_report(client,
652 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
653 report_id, buf, count, use_data);
654
655 if (report_id && ret >= 0)
656 ret++; /* add report_id to the number of transfered bytes */
657
658 mutex_unlock(&ihid->reset_lock);
659
660 return ret;
661 }
662
663 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
664 size_t count)
665 {
666 return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
667 false);
668 }
669
670 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
671 __u8 *buf, size_t len, unsigned char rtype,
672 int reqtype)
673 {
674 switch (reqtype) {
675 case HID_REQ_GET_REPORT:
676 return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
677 case HID_REQ_SET_REPORT:
678 if (buf[0] != reportnum)
679 return -EINVAL;
680 return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
681 default:
682 return -EIO;
683 }
684 }
685
686 static int i2c_hid_parse(struct hid_device *hid)
687 {
688 struct i2c_client *client = hid->driver_data;
689 struct i2c_hid *ihid = i2c_get_clientdata(client);
690 struct i2c_hid_desc *hdesc = &ihid->hdesc;
691 unsigned int rsize;
692 char *rdesc;
693 int ret;
694 int tries = 3;
695 char *use_override;
696
697 i2c_hid_dbg(ihid, "entering %s\n", __func__);
698
699 rsize = le16_to_cpu(hdesc->wReportDescLength);
700 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
701 dbg_hid("weird size of report descriptor (%u)\n", rsize);
702 return -EINVAL;
703 }
704
705 do {
706 ret = i2c_hid_hwreset(client);
707 if (ret)
708 msleep(1000);
709 } while (tries-- > 0 && ret);
710
711 if (ret)
712 return ret;
713
714 use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name,
715 &rsize);
716
717 if (use_override) {
718 rdesc = use_override;
719 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n");
720 } else {
721 rdesc = kzalloc(rsize, GFP_KERNEL);
722
723 if (!rdesc) {
724 dbg_hid("couldn't allocate rdesc memory\n");
725 return -ENOMEM;
726 }
727
728 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
729
730 ret = i2c_hid_command(client, &hid_report_descr_cmd,
731 rdesc, rsize);
732 if (ret) {
733 hid_err(hid, "reading report descriptor failed\n");
734 kfree(rdesc);
735 return -EIO;
736 }
737 }
738
739 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
740
741 ret = hid_parse_report(hid, rdesc, rsize);
742 if (!use_override)
743 kfree(rdesc);
744
745 if (ret) {
746 dbg_hid("parsing report descriptor failed\n");
747 return ret;
748 }
749
750 return 0;
751 }
752
753 static int i2c_hid_start(struct hid_device *hid)
754 {
755 struct i2c_client *client = hid->driver_data;
756 struct i2c_hid *ihid = i2c_get_clientdata(client);
757 int ret;
758 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
759
760 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
761 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
762 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
763
764 if (bufsize > ihid->bufsize) {
765 disable_irq(client->irq);
766 i2c_hid_free_buffers(ihid);
767
768 ret = i2c_hid_alloc_buffers(ihid, bufsize);
769 enable_irq(client->irq);
770
771 if (ret)
772 return ret;
773 }
774
775 return 0;
776 }
777
778 static void i2c_hid_stop(struct hid_device *hid)
779 {
780 hid->claimed = 0;
781 }
782
783 static int i2c_hid_open(struct hid_device *hid)
784 {
785 struct i2c_client *client = hid->driver_data;
786 struct i2c_hid *ihid = i2c_get_clientdata(client);
787
788 set_bit(I2C_HID_STARTED, &ihid->flags);
789 return 0;
790 }
791
792 static void i2c_hid_close(struct hid_device *hid)
793 {
794 struct i2c_client *client = hid->driver_data;
795 struct i2c_hid *ihid = i2c_get_clientdata(client);
796
797 clear_bit(I2C_HID_STARTED, &ihid->flags);
798 }
799
800 struct hid_ll_driver i2c_hid_ll_driver = {
801 .parse = i2c_hid_parse,
802 .start = i2c_hid_start,
803 .stop = i2c_hid_stop,
804 .open = i2c_hid_open,
805 .close = i2c_hid_close,
806 .output_report = i2c_hid_output_report,
807 .raw_request = i2c_hid_raw_request,
808 };
809 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
810
811 static int i2c_hid_init_irq(struct i2c_client *client)
812 {
813 struct i2c_hid *ihid = i2c_get_clientdata(client);
814 unsigned long irqflags = 0;
815 int ret;
816
817 dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
818
819 if (!irq_get_trigger_type(client->irq))
820 irqflags = IRQF_TRIGGER_LOW;
821
822 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
823 irqflags | IRQF_ONESHOT, client->name, ihid);
824 if (ret < 0) {
825 dev_warn(&client->dev,
826 "Could not register for %s interrupt, irq = %d,"
827 " ret = %d\n",
828 client->name, client->irq, ret);
829
830 return ret;
831 }
832
833 return 0;
834 }
835
836 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
837 {
838 struct i2c_client *client = ihid->client;
839 struct i2c_hid_desc *hdesc = &ihid->hdesc;
840 unsigned int dsize;
841 int ret;
842
843 /* i2c hid fetch using a fixed descriptor size (30 bytes) */
844 if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) {
845 i2c_hid_dbg(ihid, "Using a HID descriptor override\n");
846 ihid->hdesc =
847 *i2c_hid_get_dmi_i2c_hid_desc_override(client->name);
848 } else {
849 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
850 ret = i2c_hid_command(client, &hid_descr_cmd,
851 ihid->hdesc_buffer,
852 sizeof(struct i2c_hid_desc));
853 if (ret) {
854 dev_err(&client->dev, "hid_descr_cmd failed\n");
855 return -ENODEV;
856 }
857 }
858
859 /* Validate the length of HID descriptor, the 4 first bytes:
860 * bytes 0-1 -> length
861 * bytes 2-3 -> bcdVersion (has to be 1.00) */
862 /* check bcdVersion == 1.0 */
863 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
864 dev_err(&client->dev,
865 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
866 le16_to_cpu(hdesc->bcdVersion));
867 return -ENODEV;
868 }
869
870 /* Descriptor length should be 30 bytes as per the specification */
871 dsize = le16_to_cpu(hdesc->wHIDDescLength);
872 if (dsize != sizeof(struct i2c_hid_desc)) {
873 dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
874 dsize);
875 return -ENODEV;
876 }
877 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
878 return 0;
879 }
880
881 #ifdef CONFIG_ACPI
882 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {
883 /*
884 * The CHPN0001 ACPI device, which is used to describe the Chipone
885 * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible.
886 */
887 {"CHPN0001", 0 },
888 { },
889 };
890
891 static int i2c_hid_acpi_pdata(struct i2c_client *client,
892 struct i2c_hid_platform_data *pdata)
893 {
894 static guid_t i2c_hid_guid =
895 GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
896 0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
897 union acpi_object *obj;
898 struct acpi_device *adev;
899 acpi_handle handle;
900
901 handle = ACPI_HANDLE(&client->dev);
902 if (!handle || acpi_bus_get_device(handle, &adev)) {
903 dev_err(&client->dev, "Error could not get ACPI device\n");
904 return -ENODEV;
905 }
906
907 if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
908 return -ENODEV;
909
910 obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
911 ACPI_TYPE_INTEGER);
912 if (!obj) {
913 dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n");
914 return -ENODEV;
915 }
916
917 pdata->hid_descriptor_address = obj->integer.value;
918 ACPI_FREE(obj);
919
920 return 0;
921 }
922
923 static void i2c_hid_acpi_fix_up_power(struct device *dev)
924 {
925 struct acpi_device *adev;
926
927 adev = ACPI_COMPANION(dev);
928 if (adev)
929 acpi_device_fix_up_power(adev);
930 }
931
932 static const struct acpi_device_id i2c_hid_acpi_match[] = {
933 {"ACPI0C50", 0 },
934 {"PNP0C50", 0 },
935 { },
936 };
937 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
938 #else
939 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
940 struct i2c_hid_platform_data *pdata)
941 {
942 return -ENODEV;
943 }
944
945 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {}
946 #endif
947
948 #ifdef CONFIG_OF
949 static int i2c_hid_of_probe(struct i2c_client *client,
950 struct i2c_hid_platform_data *pdata)
951 {
952 struct device *dev = &client->dev;
953 u32 val;
954 int ret;
955
956 ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
957 if (ret) {
958 dev_err(&client->dev, "HID register address not provided\n");
959 return -ENODEV;
960 }
961 if (val >> 16) {
962 dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
963 val);
964 return -EINVAL;
965 }
966 pdata->hid_descriptor_address = val;
967
968 return 0;
969 }
970
971 static const struct of_device_id i2c_hid_of_match[] = {
972 { .compatible = "hid-over-i2c" },
973 {},
974 };
975 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
976 #else
977 static inline int i2c_hid_of_probe(struct i2c_client *client,
978 struct i2c_hid_platform_data *pdata)
979 {
980 return -ENODEV;
981 }
982 #endif
983
984 static void i2c_hid_fwnode_probe(struct i2c_client *client,
985 struct i2c_hid_platform_data *pdata)
986 {
987 u32 val;
988
989 if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
990 &val))
991 pdata->post_power_delay_ms = val;
992 }
993
994 static int i2c_hid_probe(struct i2c_client *client,
995 const struct i2c_device_id *dev_id)
996 {
997 int ret;
998 struct i2c_hid *ihid;
999 struct hid_device *hid;
1000 __u16 hidRegister;
1001 struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
1002
1003 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
1004
1005 if (!client->irq) {
1006 dev_err(&client->dev,
1007 "HID over i2c has not been provided an Int IRQ\n");
1008 return -EINVAL;
1009 }
1010
1011 if (client->irq < 0) {
1012 if (client->irq != -EPROBE_DEFER)
1013 dev_err(&client->dev,
1014 "HID over i2c doesn't have a valid IRQ\n");
1015 return client->irq;
1016 }
1017
1018 ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL);
1019 if (!ihid)
1020 return -ENOMEM;
1021
1022 if (client->dev.of_node) {
1023 ret = i2c_hid_of_probe(client, &ihid->pdata);
1024 if (ret)
1025 return ret;
1026 } else if (!platform_data) {
1027 ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
1028 if (ret)
1029 return ret;
1030 } else {
1031 ihid->pdata = *platform_data;
1032 }
1033
1034 /* Parse platform agnostic common properties from ACPI / device tree */
1035 i2c_hid_fwnode_probe(client, &ihid->pdata);
1036
1037 ihid->pdata.supplies[0].supply = "vdd";
1038 ihid->pdata.supplies[1].supply = "vddl";
1039
1040 ret = devm_regulator_bulk_get(&client->dev,
1041 ARRAY_SIZE(ihid->pdata.supplies),
1042 ihid->pdata.supplies);
1043 if (ret)
1044 return ret;
1045
1046 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1047 ihid->pdata.supplies);
1048 if (ret < 0)
1049 return ret;
1050
1051 if (ihid->pdata.post_power_delay_ms)
1052 msleep(ihid->pdata.post_power_delay_ms);
1053
1054 i2c_set_clientdata(client, ihid);
1055
1056 ihid->client = client;
1057
1058 hidRegister = ihid->pdata.hid_descriptor_address;
1059 ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
1060
1061 init_waitqueue_head(&ihid->wait);
1062 mutex_init(&ihid->reset_lock);
1063
1064 /* we need to allocate the command buffer without knowing the maximum
1065 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1066 * real computation later. */
1067 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1068 if (ret < 0)
1069 goto err_regulator;
1070
1071 i2c_hid_acpi_fix_up_power(&client->dev);
1072
1073 device_enable_async_suspend(&client->dev);
1074
1075 /* Make sure there is something at this address */
1076 ret = i2c_smbus_read_byte(client);
1077 if (ret < 0) {
1078 dev_dbg(&client->dev, "nothing at this address: %d\n", ret);
1079 ret = -ENXIO;
1080 goto err_regulator;
1081 }
1082
1083 ret = i2c_hid_fetch_hid_descriptor(ihid);
1084 if (ret < 0)
1085 goto err_regulator;
1086
1087 ret = i2c_hid_init_irq(client);
1088 if (ret < 0)
1089 goto err_regulator;
1090
1091 hid = hid_allocate_device();
1092 if (IS_ERR(hid)) {
1093 ret = PTR_ERR(hid);
1094 goto err_irq;
1095 }
1096
1097 ihid->hid = hid;
1098
1099 hid->driver_data = client;
1100 hid->ll_driver = &i2c_hid_ll_driver;
1101 hid->dev.parent = &client->dev;
1102 hid->bus = BUS_I2C;
1103 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1104 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1105 hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1106
1107 snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX",
1108 client->name, hid->vendor, hid->product);
1109 strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1110
1111 ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1112
1113 ret = hid_add_device(hid);
1114 if (ret) {
1115 if (ret != -ENODEV)
1116 hid_err(client, "can't add hid device: %d\n", ret);
1117 goto err_mem_free;
1118 }
1119
1120 return 0;
1121
1122 err_mem_free:
1123 hid_destroy_device(hid);
1124
1125 err_irq:
1126 free_irq(client->irq, ihid);
1127
1128 err_regulator:
1129 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1130 ihid->pdata.supplies);
1131 i2c_hid_free_buffers(ihid);
1132 return ret;
1133 }
1134
1135 static int i2c_hid_remove(struct i2c_client *client)
1136 {
1137 struct i2c_hid *ihid = i2c_get_clientdata(client);
1138 struct hid_device *hid;
1139
1140 hid = ihid->hid;
1141 hid_destroy_device(hid);
1142
1143 free_irq(client->irq, ihid);
1144
1145 if (ihid->bufsize)
1146 i2c_hid_free_buffers(ihid);
1147
1148 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1149 ihid->pdata.supplies);
1150
1151 return 0;
1152 }
1153
1154 static void i2c_hid_shutdown(struct i2c_client *client)
1155 {
1156 struct i2c_hid *ihid = i2c_get_clientdata(client);
1157
1158 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1159 free_irq(client->irq, ihid);
1160 }
1161
1162 #ifdef CONFIG_PM_SLEEP
1163 static int i2c_hid_suspend(struct device *dev)
1164 {
1165 struct i2c_client *client = to_i2c_client(dev);
1166 struct i2c_hid *ihid = i2c_get_clientdata(client);
1167 struct hid_device *hid = ihid->hid;
1168 int ret;
1169 int wake_status;
1170
1171 if (hid->driver && hid->driver->suspend) {
1172 ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1173 if (ret < 0)
1174 return ret;
1175 }
1176
1177 /* Save some power */
1178 i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1179
1180 disable_irq(client->irq);
1181
1182 if (device_may_wakeup(&client->dev)) {
1183 wake_status = enable_irq_wake(client->irq);
1184 if (!wake_status)
1185 ihid->irq_wake_enabled = true;
1186 else
1187 hid_warn(hid, "Failed to enable irq wake: %d\n",
1188 wake_status);
1189 } else {
1190 regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1191 ihid->pdata.supplies);
1192 }
1193
1194 return 0;
1195 }
1196
1197 static int i2c_hid_resume(struct device *dev)
1198 {
1199 int ret;
1200 struct i2c_client *client = to_i2c_client(dev);
1201 struct i2c_hid *ihid = i2c_get_clientdata(client);
1202 struct hid_device *hid = ihid->hid;
1203 int wake_status;
1204
1205 if (!device_may_wakeup(&client->dev)) {
1206 ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1207 ihid->pdata.supplies);
1208 if (ret)
1209 hid_warn(hid, "Failed to enable supplies: %d\n", ret);
1210
1211 if (ihid->pdata.post_power_delay_ms)
1212 msleep(ihid->pdata.post_power_delay_ms);
1213 } else if (ihid->irq_wake_enabled) {
1214 wake_status = disable_irq_wake(client->irq);
1215 if (!wake_status)
1216 ihid->irq_wake_enabled = false;
1217 else
1218 hid_warn(hid, "Failed to disable irq wake: %d\n",
1219 wake_status);
1220 }
1221
1222 enable_irq(client->irq);
1223
1224 /* Instead of resetting device, simply powers the device on. This
1225 * solves "incomplete reports" on Raydium devices 2386:3118 and
1226 * 2386:4B33 and fixes various SIS touchscreens no longer sending
1227 * data after a suspend/resume.
1228 *
1229 * However some ALPS touchpads generate IRQ storm without reset, so
1230 * let's still reset them here.
1231 */
1232 if (ihid->quirks & I2C_HID_QUIRK_RESET_ON_RESUME)
1233 ret = i2c_hid_hwreset(client);
1234 else
1235 ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
1236
1237 if (ret)
1238 return ret;
1239
1240 if (hid->driver && hid->driver->reset_resume) {
1241 ret = hid->driver->reset_resume(hid);
1242 return ret;
1243 }
1244
1245 return 0;
1246 }
1247 #endif
1248
1249 static const struct dev_pm_ops i2c_hid_pm = {
1250 SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1251 };
1252
1253 static const struct i2c_device_id i2c_hid_id_table[] = {
1254 { "hid", 0 },
1255 { "hid-over-i2c", 0 },
1256 { },
1257 };
1258 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1259
1260
1261 static struct i2c_driver i2c_hid_driver = {
1262 .driver = {
1263 .name = "i2c_hid",
1264 .pm = &i2c_hid_pm,
1265 .acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1266 .of_match_table = of_match_ptr(i2c_hid_of_match),
1267 },
1268
1269 .probe = i2c_hid_probe,
1270 .remove = i2c_hid_remove,
1271 .shutdown = i2c_hid_shutdown,
1272 .id_table = i2c_hid_id_table,
1273 };
1274
1275 module_i2c_driver(i2c_hid_driver);
1276
1277 MODULE_DESCRIPTION("HID over I2C core driver");
1278 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1279 MODULE_LICENSE("GPL");
Linux with added FPC-III support