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_wakeirq.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 <asm/unaligned.h>
40
41 #include <drm/drm_panel.h>
42
43 #include "../hid-ids.h"
44 #include "i2c-hid.h"
45
46 /* quirks to control the device */
47 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET BIT(0)
48 #define I2C_HID_QUIRK_BOGUS_IRQ BIT(1)
49 #define I2C_HID_QUIRK_RESET_ON_RESUME BIT(2)
50 #define I2C_HID_QUIRK_BAD_INPUT_SIZE BIT(3)
51 #define I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET BIT(4)
52 #define I2C_HID_QUIRK_NO_SLEEP_ON_SUSPEND BIT(5)
53
54 /* Command opcodes */
55 #define I2C_HID_OPCODE_RESET 0x01
56 #define I2C_HID_OPCODE_GET_REPORT 0x02
57 #define I2C_HID_OPCODE_SET_REPORT 0x03
58 #define I2C_HID_OPCODE_GET_IDLE 0x04
59 #define I2C_HID_OPCODE_SET_IDLE 0x05
60 #define I2C_HID_OPCODE_GET_PROTOCOL 0x06
61 #define I2C_HID_OPCODE_SET_PROTOCOL 0x07
62 #define I2C_HID_OPCODE_SET_POWER 0x08
63
64 /* flags */
65 #define I2C_HID_STARTED 0
66 #define I2C_HID_RESET_PENDING 1
67
68 #define I2C_HID_PWR_ON 0x00
69 #define I2C_HID_PWR_SLEEP 0x01
70
71 #define i2c_hid_dbg(ihid, ...) dev_dbg(&(ihid)->client->dev, __VA_ARGS__)
72
73 struct i2c_hid_desc {
74 __le16 wHIDDescLength;
75 __le16 bcdVersion;
76 __le16 wReportDescLength;
77 __le16 wReportDescRegister;
78 __le16 wInputRegister;
79 __le16 wMaxInputLength;
80 __le16 wOutputRegister;
81 __le16 wMaxOutputLength;
82 __le16 wCommandRegister;
83 __le16 wDataRegister;
84 __le16 wVendorID;
85 __le16 wProductID;
86 __le16 wVersionID;
87 __le32 reserved;
88 } __packed;
89
90 /* The main device structure */
91 struct i2c_hid {
92 struct i2c_client *client; /* i2c client */
93 struct hid_device *hid; /* pointer to corresponding HID dev */
94 struct i2c_hid_desc hdesc; /* the HID Descriptor */
95 __le16 wHIDDescRegister; /* location of the i2c
96 * register of the HID
97 * descriptor. */
98 unsigned int bufsize; /* i2c buffer size */
99 u8 *inbuf; /* Input buffer */
100 u8 *rawbuf; /* Raw Input buffer */
101 u8 *cmdbuf; /* Command buffer */
102
103 unsigned long flags; /* device flags */
104 unsigned long quirks; /* Various quirks */
105
106 wait_queue_head_t wait; /* For waiting the interrupt */
107
108 struct mutex reset_lock;
109
110 struct i2chid_ops *ops;
111 struct drm_panel_follower panel_follower;
112 struct work_struct panel_follower_prepare_work;
113 bool is_panel_follower;
114 bool prepare_work_finished;
115 };
116
117 static const struct i2c_hid_quirks {
118 __u16 idVendor;
119 __u16 idProduct;
120 __u32 quirks;
121 } i2c_hid_quirks[] = {
122 { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
123 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
124 { I2C_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_VOYO_WINPAD_A15,
125 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
126 { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_3118,
127 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
128 { USB_VENDOR_ID_ALPS_JP, HID_ANY_ID,
129 I2C_HID_QUIRK_RESET_ON_RESUME },
130 { I2C_VENDOR_ID_SYNAPTICS, I2C_PRODUCT_ID_SYNAPTICS_SYNA2393,
131 I2C_HID_QUIRK_RESET_ON_RESUME },
132 { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
133 I2C_HID_QUIRK_BAD_INPUT_SIZE },
134 { I2C_VENDOR_ID_CIRQUE, I2C_PRODUCT_ID_CIRQUE_1063,
135 I2C_HID_QUIRK_NO_SLEEP_ON_SUSPEND },
136 /*
137 * Sending the wakeup after reset actually break ELAN touchscreen controller
138 */
139 { USB_VENDOR_ID_ELAN, HID_ANY_ID,
140 I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET |
141 I2C_HID_QUIRK_BOGUS_IRQ },
142 { 0, 0 }
143 };
144
145 /*
146 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
147 * @idVendor: the 16-bit vendor ID
148 * @idProduct: the 16-bit product ID
149 *
150 * Returns: a u32 quirks value.
151 */
i2c_hid_lookup_quirk(const u16 idVendor,const u16 idProduct)152 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
153 {
154 u32 quirks = 0;
155 int n;
156
157 for (n = 0; i2c_hid_quirks[n].idVendor; n++)
158 if (i2c_hid_quirks[n].idVendor == idVendor &&
159 (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
160 i2c_hid_quirks[n].idProduct == idProduct))
161 quirks = i2c_hid_quirks[n].quirks;
162
163 return quirks;
164 }
165
i2c_hid_probe_address(struct i2c_hid * ihid)166 static int i2c_hid_probe_address(struct i2c_hid *ihid)
167 {
168 int ret;
169
170 /*
171 * Some STM-based devices need 400µs after a rising clock edge to wake
172 * from deep sleep, in which case the first read will fail. Try after a
173 * short sleep to see if the device came alive on the bus. Certain
174 * Weida Tech devices also need this.
175 */
176 ret = i2c_smbus_read_byte(ihid->client);
177 if (ret < 0) {
178 usleep_range(400, 500);
179 ret = i2c_smbus_read_byte(ihid->client);
180 }
181 return ret < 0 ? ret : 0;
182 }
183
i2c_hid_xfer(struct i2c_hid * ihid,u8 * send_buf,int send_len,u8 * recv_buf,int recv_len)184 static int i2c_hid_xfer(struct i2c_hid *ihid,
185 u8 *send_buf, int send_len, u8 *recv_buf, int recv_len)
186 {
187 struct i2c_client *client = ihid->client;
188 struct i2c_msg msgs[2] = { 0 };
189 int n = 0;
190 int ret;
191
192 if (send_len) {
193 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n",
194 __func__, send_len, send_buf);
195
196 msgs[n].addr = client->addr;
197 msgs[n].flags = (client->flags & I2C_M_TEN) | I2C_M_DMA_SAFE;
198 msgs[n].len = send_len;
199 msgs[n].buf = send_buf;
200 n++;
201 }
202
203 if (recv_len) {
204 msgs[n].addr = client->addr;
205 msgs[n].flags = (client->flags & I2C_M_TEN) |
206 I2C_M_RD | I2C_M_DMA_SAFE;
207 msgs[n].len = recv_len;
208 msgs[n].buf = recv_buf;
209 n++;
210 }
211
212 ret = i2c_transfer(client->adapter, msgs, n);
213
214 if (ret != n)
215 return ret < 0 ? ret : -EIO;
216
217 return 0;
218 }
219
i2c_hid_read_register(struct i2c_hid * ihid,__le16 reg,void * buf,size_t len)220 static int i2c_hid_read_register(struct i2c_hid *ihid, __le16 reg,
221 void *buf, size_t len)
222 {
223 *(__le16 *)ihid->cmdbuf = reg;
224
225 return i2c_hid_xfer(ihid, ihid->cmdbuf, sizeof(__le16), buf, len);
226 }
227
i2c_hid_encode_command(u8 * buf,u8 opcode,int report_type,int report_id)228 static size_t i2c_hid_encode_command(u8 *buf, u8 opcode,
229 int report_type, int report_id)
230 {
231 size_t length = 0;
232
233 if (report_id < 0x0F) {
234 buf[length++] = report_type << 4 | report_id;
235 buf[length++] = opcode;
236 } else {
237 buf[length++] = report_type << 4 | 0x0F;
238 buf[length++] = opcode;
239 buf[length++] = report_id;
240 }
241
242 return length;
243 }
244
i2c_hid_get_report(struct i2c_hid * ihid,u8 report_type,u8 report_id,u8 * recv_buf,size_t recv_len)245 static int i2c_hid_get_report(struct i2c_hid *ihid,
246 u8 report_type, u8 report_id,
247 u8 *recv_buf, size_t recv_len)
248 {
249 size_t length = 0;
250 size_t ret_count;
251 int error;
252
253 i2c_hid_dbg(ihid, "%s\n", __func__);
254
255 /* Command register goes first */
256 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
257 length += sizeof(__le16);
258 /* Next is GET_REPORT command */
259 length += i2c_hid_encode_command(ihid->cmdbuf + length,
260 I2C_HID_OPCODE_GET_REPORT,
261 report_type, report_id);
262 /*
263 * Device will send report data through data register. Because
264 * command can be either 2 or 3 bytes destination for the data
265 * register may be not aligned.
266 */
267 put_unaligned_le16(le16_to_cpu(ihid->hdesc.wDataRegister),
268 ihid->cmdbuf + length);
269 length += sizeof(__le16);
270
271 /*
272 * In addition to report data device will supply data length
273 * in the first 2 bytes of the response, so adjust .
274 */
275 error = i2c_hid_xfer(ihid, ihid->cmdbuf, length,
276 ihid->rawbuf, recv_len + sizeof(__le16));
277 if (error) {
278 dev_err(&ihid->client->dev,
279 "failed to set a report to device: %d\n", error);
280 return error;
281 }
282
283 /* The buffer is sufficiently aligned */
284 ret_count = le16_to_cpup((__le16 *)ihid->rawbuf);
285
286 /* Check for empty report response */
287 if (ret_count <= sizeof(__le16))
288 return 0;
289
290 recv_len = min(recv_len, ret_count - sizeof(__le16));
291 memcpy(recv_buf, ihid->rawbuf + sizeof(__le16), recv_len);
292
293 if (report_id && recv_len != 0 && recv_buf[0] != report_id) {
294 dev_err(&ihid->client->dev,
295 "device returned incorrect report (%d vs %d expected)\n",
296 recv_buf[0], report_id);
297 return -EINVAL;
298 }
299
300 return recv_len;
301 }
302
i2c_hid_format_report(u8 * buf,int report_id,const u8 * data,size_t size)303 static size_t i2c_hid_format_report(u8 *buf, int report_id,
304 const u8 *data, size_t size)
305 {
306 size_t length = sizeof(__le16); /* reserve space to store size */
307
308 if (report_id)
309 buf[length++] = report_id;
310
311 memcpy(buf + length, data, size);
312 length += size;
313
314 /* Store overall size in the beginning of the buffer */
315 put_unaligned_le16(length, buf);
316
317 return length;
318 }
319
320 /**
321 * i2c_hid_set_or_send_report: forward an incoming report to the device
322 * @ihid: the i2c hid device
323 * @report_type: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
324 * @report_id: the report ID
325 * @buf: the actual data to transfer, without the report ID
326 * @data_len: size of buf
327 * @do_set: true: use SET_REPORT HID command, false: send plain OUTPUT report
328 */
i2c_hid_set_or_send_report(struct i2c_hid * ihid,u8 report_type,u8 report_id,const u8 * buf,size_t data_len,bool do_set)329 static int i2c_hid_set_or_send_report(struct i2c_hid *ihid,
330 u8 report_type, u8 report_id,
331 const u8 *buf, size_t data_len,
332 bool do_set)
333 {
334 size_t length = 0;
335 int error;
336
337 i2c_hid_dbg(ihid, "%s\n", __func__);
338
339 if (data_len > ihid->bufsize)
340 return -EINVAL;
341
342 if (!do_set && le16_to_cpu(ihid->hdesc.wMaxOutputLength) == 0)
343 return -ENOSYS;
344
345 if (do_set) {
346 /* Command register goes first */
347 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
348 length += sizeof(__le16);
349 /* Next is SET_REPORT command */
350 length += i2c_hid_encode_command(ihid->cmdbuf + length,
351 I2C_HID_OPCODE_SET_REPORT,
352 report_type, report_id);
353 /*
354 * Report data will go into the data register. Because
355 * command can be either 2 or 3 bytes destination for
356 * the data register may be not aligned.
357 */
358 put_unaligned_le16(le16_to_cpu(ihid->hdesc.wDataRegister),
359 ihid->cmdbuf + length);
360 length += sizeof(__le16);
361 } else {
362 /*
363 * With simple "send report" all data goes into the output
364 * register.
365 */
366 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wOutputRegister;
367 length += sizeof(__le16);
368 }
369
370 length += i2c_hid_format_report(ihid->cmdbuf + length,
371 report_id, buf, data_len);
372
373 error = i2c_hid_xfer(ihid, ihid->cmdbuf, length, NULL, 0);
374 if (error) {
375 dev_err(&ihid->client->dev,
376 "failed to set a report to device: %d\n", error);
377 return error;
378 }
379
380 return data_len;
381 }
382
i2c_hid_set_power_command(struct i2c_hid * ihid,int power_state)383 static int i2c_hid_set_power_command(struct i2c_hid *ihid, int power_state)
384 {
385 size_t length;
386
387 /* SET_POWER uses command register */
388 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
389 length = sizeof(__le16);
390
391 /* Now the command itself */
392 length += i2c_hid_encode_command(ihid->cmdbuf + length,
393 I2C_HID_OPCODE_SET_POWER,
394 0, power_state);
395
396 return i2c_hid_xfer(ihid, ihid->cmdbuf, length, NULL, 0);
397 }
398
i2c_hid_set_power(struct i2c_hid * ihid,int power_state)399 static int i2c_hid_set_power(struct i2c_hid *ihid, int power_state)
400 {
401 int ret;
402
403 i2c_hid_dbg(ihid, "%s\n", __func__);
404
405 ret = i2c_hid_set_power_command(ihid, power_state);
406 if (ret)
407 dev_err(&ihid->client->dev,
408 "failed to change power setting.\n");
409
410 /*
411 * The HID over I2C specification states that if a DEVICE needs time
412 * after the PWR_ON request, it should utilise CLOCK stretching.
413 * However, it has been observered that the Windows driver provides a
414 * 1ms sleep between the PWR_ON and RESET requests.
415 * According to Goodix Windows even waits 60 ms after (other?)
416 * PWR_ON requests. Testing has confirmed that several devices
417 * will not work properly without a delay after a PWR_ON request.
418 */
419 if (!ret && power_state == I2C_HID_PWR_ON)
420 msleep(60);
421
422 return ret;
423 }
424
i2c_hid_start_hwreset(struct i2c_hid * ihid)425 static int i2c_hid_start_hwreset(struct i2c_hid *ihid)
426 {
427 size_t length = 0;
428 int ret;
429
430 i2c_hid_dbg(ihid, "%s\n", __func__);
431
432 /*
433 * This prevents sending feature reports while the device is
434 * being reset. Otherwise we may lose the reset complete
435 * interrupt.
436 */
437 lockdep_assert_held(&ihid->reset_lock);
438
439 ret = i2c_hid_set_power(ihid, I2C_HID_PWR_ON);
440 if (ret)
441 return ret;
442
443 /* Prepare reset command. Command register goes first. */
444 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
445 length += sizeof(__le16);
446 /* Next is RESET command itself */
447 length += i2c_hid_encode_command(ihid->cmdbuf + length,
448 I2C_HID_OPCODE_RESET, 0, 0);
449
450 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
451
452 ret = i2c_hid_xfer(ihid, ihid->cmdbuf, length, NULL, 0);
453 if (ret) {
454 dev_err(&ihid->client->dev,
455 "failed to reset device: %d\n", ret);
456 goto err_clear_reset;
457 }
458
459 return 0;
460
461 err_clear_reset:
462 clear_bit(I2C_HID_RESET_PENDING, &ihid->flags);
463 i2c_hid_set_power(ihid, I2C_HID_PWR_SLEEP);
464 return ret;
465 }
466
i2c_hid_finish_hwreset(struct i2c_hid * ihid)467 static int i2c_hid_finish_hwreset(struct i2c_hid *ihid)
468 {
469 int ret = 0;
470
471 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
472
473 if (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET) {
474 msleep(100);
475 clear_bit(I2C_HID_RESET_PENDING, &ihid->flags);
476 } else if (!wait_event_timeout(ihid->wait,
477 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
478 msecs_to_jiffies(1000))) {
479 dev_warn(&ihid->client->dev, "device did not ack reset within 1000 ms\n");
480 clear_bit(I2C_HID_RESET_PENDING, &ihid->flags);
481 }
482 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
483
484 /* At least some SIS devices need this after reset */
485 if (!(ihid->quirks & I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET))
486 ret = i2c_hid_set_power(ihid, I2C_HID_PWR_ON);
487
488 return ret;
489 }
490
i2c_hid_get_input(struct i2c_hid * ihid)491 static void i2c_hid_get_input(struct i2c_hid *ihid)
492 {
493 u16 size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
494 u16 ret_size;
495 int ret;
496
497 if (size > ihid->bufsize)
498 size = ihid->bufsize;
499
500 ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
501 if (ret != size) {
502 if (ret < 0)
503 return;
504
505 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
506 __func__, ret, size);
507 return;
508 }
509
510 /* Receiving buffer is properly aligned */
511 ret_size = le16_to_cpup((__le16 *)ihid->inbuf);
512 if (!ret_size) {
513 /* host or device initiated RESET completed */
514 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
515 wake_up(&ihid->wait);
516 return;
517 }
518
519 if ((ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ) && ret_size == 0xffff) {
520 dev_warn_once(&ihid->client->dev,
521 "%s: IRQ triggered but there's no data\n",
522 __func__);
523 return;
524 }
525
526 if (ret_size > size || ret_size < sizeof(__le16)) {
527 if (ihid->quirks & I2C_HID_QUIRK_BAD_INPUT_SIZE) {
528 *(__le16 *)ihid->inbuf = cpu_to_le16(size);
529 ret_size = size;
530 } else {
531 dev_err(&ihid->client->dev,
532 "%s: incomplete report (%d/%d)\n",
533 __func__, size, ret_size);
534 return;
535 }
536 }
537
538 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
539
540 if (test_bit(I2C_HID_STARTED, &ihid->flags)) {
541 if (ihid->hid->group != HID_GROUP_RMI)
542 pm_wakeup_event(&ihid->client->dev, 0);
543
544 hid_input_report(ihid->hid, HID_INPUT_REPORT,
545 ihid->inbuf + sizeof(__le16),
546 ret_size - sizeof(__le16), 1);
547 }
548
549 return;
550 }
551
i2c_hid_irq(int irq,void * dev_id)552 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
553 {
554 struct i2c_hid *ihid = dev_id;
555
556 i2c_hid_get_input(ihid);
557
558 return IRQ_HANDLED;
559 }
560
i2c_hid_get_report_length(struct hid_report * report)561 static int i2c_hid_get_report_length(struct hid_report *report)
562 {
563 return ((report->size - 1) >> 3) + 1 +
564 report->device->report_enum[report->type].numbered + 2;
565 }
566
567 /*
568 * Traverse the supplied list of reports and find the longest
569 */
i2c_hid_find_max_report(struct hid_device * hid,unsigned int type,unsigned int * max)570 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
571 unsigned int *max)
572 {
573 struct hid_report *report;
574 unsigned int size;
575
576 /* We should not rely on wMaxInputLength, as some devices may set it to
577 * a wrong length. */
578 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
579 size = i2c_hid_get_report_length(report);
580 if (*max < size)
581 *max = size;
582 }
583 }
584
i2c_hid_free_buffers(struct i2c_hid * ihid)585 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
586 {
587 kfree(ihid->inbuf);
588 kfree(ihid->rawbuf);
589 kfree(ihid->cmdbuf);
590 ihid->inbuf = NULL;
591 ihid->rawbuf = NULL;
592 ihid->cmdbuf = NULL;
593 ihid->bufsize = 0;
594 }
595
i2c_hid_alloc_buffers(struct i2c_hid * ihid,size_t report_size)596 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
597 {
598 /*
599 * The worst case is computed from the set_report command with a
600 * reportID > 15 and the maximum report length.
601 */
602 int cmd_len = sizeof(__le16) + /* command register */
603 sizeof(u8) + /* encoded report type/ID */
604 sizeof(u8) + /* opcode */
605 sizeof(u8) + /* optional 3rd byte report ID */
606 sizeof(__le16) + /* data register */
607 sizeof(__le16) + /* report data size */
608 sizeof(u8) + /* report ID if numbered report */
609 report_size;
610
611 ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
612 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
613 ihid->cmdbuf = kzalloc(cmd_len, GFP_KERNEL);
614
615 if (!ihid->inbuf || !ihid->rawbuf || !ihid->cmdbuf) {
616 i2c_hid_free_buffers(ihid);
617 return -ENOMEM;
618 }
619
620 ihid->bufsize = report_size;
621
622 return 0;
623 }
624
i2c_hid_get_raw_report(struct hid_device * hid,u8 report_type,u8 report_id,u8 * buf,size_t count)625 static int i2c_hid_get_raw_report(struct hid_device *hid,
626 u8 report_type, u8 report_id,
627 u8 *buf, size_t count)
628 {
629 struct i2c_client *client = hid->driver_data;
630 struct i2c_hid *ihid = i2c_get_clientdata(client);
631 int ret_count;
632
633 if (report_type == HID_OUTPUT_REPORT)
634 return -EINVAL;
635
636 /*
637 * In case of unnumbered reports the response from the device will
638 * not have the report ID that the upper layers expect, so we need
639 * to stash it the buffer ourselves and adjust the data size.
640 */
641 if (!report_id) {
642 buf[0] = 0;
643 buf++;
644 count--;
645 }
646
647 ret_count = i2c_hid_get_report(ihid,
648 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
649 report_id, buf, count);
650
651 if (ret_count > 0 && !report_id)
652 ret_count++;
653
654 return ret_count;
655 }
656
i2c_hid_output_raw_report(struct hid_device * hid,u8 report_type,const u8 * buf,size_t count,bool do_set)657 static int i2c_hid_output_raw_report(struct hid_device *hid, u8 report_type,
658 const u8 *buf, size_t count, bool do_set)
659 {
660 struct i2c_client *client = hid->driver_data;
661 struct i2c_hid *ihid = i2c_get_clientdata(client);
662 int report_id = buf[0];
663 int ret;
664
665 if (report_type == HID_INPUT_REPORT)
666 return -EINVAL;
667
668 mutex_lock(&ihid->reset_lock);
669
670 /*
671 * Note that both numbered and unnumbered reports passed here
672 * are supposed to have report ID stored in the 1st byte of the
673 * buffer, so we strip it off unconditionally before passing payload
674 * to i2c_hid_set_or_send_report which takes care of encoding
675 * everything properly.
676 */
677 ret = i2c_hid_set_or_send_report(ihid,
678 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
679 report_id, buf + 1, count - 1, do_set);
680
681 if (ret >= 0)
682 ret++; /* add report_id to the number of transferred bytes */
683
684 mutex_unlock(&ihid->reset_lock);
685
686 return ret;
687 }
688
i2c_hid_output_report(struct hid_device * hid,u8 * buf,size_t count)689 static int i2c_hid_output_report(struct hid_device *hid, u8 *buf, size_t count)
690 {
691 return i2c_hid_output_raw_report(hid, HID_OUTPUT_REPORT, buf, count,
692 false);
693 }
694
i2c_hid_raw_request(struct hid_device * hid,unsigned char reportnum,__u8 * buf,size_t len,unsigned char rtype,int reqtype)695 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
696 __u8 *buf, size_t len, unsigned char rtype,
697 int reqtype)
698 {
699 switch (reqtype) {
700 case HID_REQ_GET_REPORT:
701 return i2c_hid_get_raw_report(hid, rtype, reportnum, buf, len);
702 case HID_REQ_SET_REPORT:
703 if (buf[0] != reportnum)
704 return -EINVAL;
705 return i2c_hid_output_raw_report(hid, rtype, buf, len, true);
706 default:
707 return -EIO;
708 }
709 }
710
i2c_hid_parse(struct hid_device * hid)711 static int i2c_hid_parse(struct hid_device *hid)
712 {
713 struct i2c_client *client = hid->driver_data;
714 struct i2c_hid *ihid = i2c_get_clientdata(client);
715 struct i2c_hid_desc *hdesc = &ihid->hdesc;
716 char *rdesc = NULL, *use_override = NULL;
717 unsigned int rsize;
718 int ret;
719 int tries = 3;
720
721 i2c_hid_dbg(ihid, "entering %s\n", __func__);
722
723 rsize = le16_to_cpu(hdesc->wReportDescLength);
724 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
725 dbg_hid("weird size of report descriptor (%u)\n", rsize);
726 return -EINVAL;
727 }
728
729 mutex_lock(&ihid->reset_lock);
730 do {
731 ret = i2c_hid_start_hwreset(ihid);
732 if (ret == 0)
733 ret = i2c_hid_finish_hwreset(ihid);
734 else
735 msleep(1000);
736 } while (tries-- > 0 && ret);
737 mutex_unlock(&ihid->reset_lock);
738
739 if (ret)
740 return ret;
741
742 use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name,
743 &rsize);
744
745 if (use_override) {
746 rdesc = use_override;
747 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n");
748 } else {
749 rdesc = kzalloc(rsize, GFP_KERNEL);
750 if (!rdesc)
751 return -ENOMEM;
752
753 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
754
755 ret = i2c_hid_read_register(ihid,
756 ihid->hdesc.wReportDescRegister,
757 rdesc, rsize);
758 if (ret) {
759 hid_err(hid, "reading report descriptor failed\n");
760 goto out;
761 }
762 }
763
764 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
765
766 ret = hid_parse_report(hid, rdesc, rsize);
767 if (ret)
768 dbg_hid("parsing report descriptor failed\n");
769
770 out:
771 if (!use_override)
772 kfree(rdesc);
773
774 return ret;
775 }
776
i2c_hid_start(struct hid_device * hid)777 static int i2c_hid_start(struct hid_device *hid)
778 {
779 struct i2c_client *client = hid->driver_data;
780 struct i2c_hid *ihid = i2c_get_clientdata(client);
781 int ret;
782 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
783
784 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
785 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
786 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
787
788 if (bufsize > ihid->bufsize) {
789 disable_irq(client->irq);
790 i2c_hid_free_buffers(ihid);
791
792 ret = i2c_hid_alloc_buffers(ihid, bufsize);
793 enable_irq(client->irq);
794
795 if (ret)
796 return ret;
797 }
798
799 return 0;
800 }
801
i2c_hid_stop(struct hid_device * hid)802 static void i2c_hid_stop(struct hid_device *hid)
803 {
804 hid->claimed = 0;
805 }
806
i2c_hid_open(struct hid_device * hid)807 static int i2c_hid_open(struct hid_device *hid)
808 {
809 struct i2c_client *client = hid->driver_data;
810 struct i2c_hid *ihid = i2c_get_clientdata(client);
811
812 set_bit(I2C_HID_STARTED, &ihid->flags);
813 return 0;
814 }
815
i2c_hid_close(struct hid_device * hid)816 static void i2c_hid_close(struct hid_device *hid)
817 {
818 struct i2c_client *client = hid->driver_data;
819 struct i2c_hid *ihid = i2c_get_clientdata(client);
820
821 clear_bit(I2C_HID_STARTED, &ihid->flags);
822 }
823
824 static const struct hid_ll_driver i2c_hid_ll_driver = {
825 .parse = i2c_hid_parse,
826 .start = i2c_hid_start,
827 .stop = i2c_hid_stop,
828 .open = i2c_hid_open,
829 .close = i2c_hid_close,
830 .output_report = i2c_hid_output_report,
831 .raw_request = i2c_hid_raw_request,
832 };
833
i2c_hid_init_irq(struct i2c_client * client)834 static int i2c_hid_init_irq(struct i2c_client *client)
835 {
836 struct i2c_hid *ihid = i2c_get_clientdata(client);
837 unsigned long irqflags = 0;
838 int ret;
839
840 i2c_hid_dbg(ihid, "Requesting IRQ: %d\n", client->irq);
841
842 if (!irq_get_trigger_type(client->irq))
843 irqflags = IRQF_TRIGGER_LOW;
844
845 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
846 irqflags | IRQF_ONESHOT | IRQF_NO_AUTOEN,
847 client->name, ihid);
848 if (ret < 0) {
849 dev_warn(&client->dev,
850 "Could not register for %s interrupt, irq = %d,"
851 " ret = %d\n",
852 client->name, client->irq, ret);
853
854 return ret;
855 }
856
857 return 0;
858 }
859
i2c_hid_fetch_hid_descriptor(struct i2c_hid * ihid)860 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
861 {
862 struct i2c_client *client = ihid->client;
863 struct i2c_hid_desc *hdesc = &ihid->hdesc;
864 unsigned int dsize;
865 int error;
866
867 /* i2c hid fetch using a fixed descriptor size (30 bytes) */
868 if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) {
869 i2c_hid_dbg(ihid, "Using a HID descriptor override\n");
870 ihid->hdesc =
871 *i2c_hid_get_dmi_i2c_hid_desc_override(client->name);
872 } else {
873 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
874 error = i2c_hid_read_register(ihid,
875 ihid->wHIDDescRegister,
876 &ihid->hdesc,
877 sizeof(ihid->hdesc));
878 if (error) {
879 dev_err(&ihid->client->dev,
880 "failed to fetch HID descriptor: %d\n",
881 error);
882 return -ENODEV;
883 }
884 }
885
886 /* Validate the length of HID descriptor, the 4 first bytes:
887 * bytes 0-1 -> length
888 * bytes 2-3 -> bcdVersion (has to be 1.00) */
889 /* check bcdVersion == 1.0 */
890 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
891 dev_err(&ihid->client->dev,
892 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
893 le16_to_cpu(hdesc->bcdVersion));
894 return -ENODEV;
895 }
896
897 /* Descriptor length should be 30 bytes as per the specification */
898 dsize = le16_to_cpu(hdesc->wHIDDescLength);
899 if (dsize != sizeof(struct i2c_hid_desc)) {
900 dev_err(&ihid->client->dev,
901 "weird size of HID descriptor (%u)\n", dsize);
902 return -ENODEV;
903 }
904 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, &ihid->hdesc);
905 return 0;
906 }
907
i2c_hid_core_power_up(struct i2c_hid * ihid)908 static int i2c_hid_core_power_up(struct i2c_hid *ihid)
909 {
910 if (!ihid->ops->power_up)
911 return 0;
912
913 return ihid->ops->power_up(ihid->ops);
914 }
915
i2c_hid_core_power_down(struct i2c_hid * ihid)916 static void i2c_hid_core_power_down(struct i2c_hid *ihid)
917 {
918 if (!ihid->ops->power_down)
919 return;
920
921 ihid->ops->power_down(ihid->ops);
922 }
923
i2c_hid_core_shutdown_tail(struct i2c_hid * ihid)924 static void i2c_hid_core_shutdown_tail(struct i2c_hid *ihid)
925 {
926 if (!ihid->ops->shutdown_tail)
927 return;
928
929 ihid->ops->shutdown_tail(ihid->ops);
930 }
931
i2c_hid_core_suspend(struct i2c_hid * ihid,bool force_poweroff)932 static int i2c_hid_core_suspend(struct i2c_hid *ihid, bool force_poweroff)
933 {
934 struct i2c_client *client = ihid->client;
935 struct hid_device *hid = ihid->hid;
936 int ret;
937
938 ret = hid_driver_suspend(hid, PMSG_SUSPEND);
939 if (ret < 0)
940 return ret;
941
942 /* Save some power */
943 if (!(ihid->quirks & I2C_HID_QUIRK_NO_SLEEP_ON_SUSPEND))
944 i2c_hid_set_power(ihid, I2C_HID_PWR_SLEEP);
945
946 disable_irq(client->irq);
947
948 if (force_poweroff || !device_may_wakeup(&client->dev))
949 i2c_hid_core_power_down(ihid);
950
951 return 0;
952 }
953
i2c_hid_core_resume(struct i2c_hid * ihid)954 static int i2c_hid_core_resume(struct i2c_hid *ihid)
955 {
956 struct i2c_client *client = ihid->client;
957 struct hid_device *hid = ihid->hid;
958 int ret;
959
960 if (!device_may_wakeup(&client->dev))
961 i2c_hid_core_power_up(ihid);
962
963 enable_irq(client->irq);
964
965 /* Make sure the device is awake on the bus */
966 ret = i2c_hid_probe_address(ihid);
967 if (ret < 0) {
968 dev_err(&client->dev, "nothing at address after resume: %d\n",
969 ret);
970 return -ENXIO;
971 }
972
973 /* Instead of resetting device, simply powers the device on. This
974 * solves "incomplete reports" on Raydium devices 2386:3118 and
975 * 2386:4B33 and fixes various SIS touchscreens no longer sending
976 * data after a suspend/resume.
977 *
978 * However some ALPS touchpads generate IRQ storm without reset, so
979 * let's still reset them here.
980 */
981 if (ihid->quirks & I2C_HID_QUIRK_RESET_ON_RESUME) {
982 mutex_lock(&ihid->reset_lock);
983 ret = i2c_hid_start_hwreset(ihid);
984 if (ret == 0)
985 ret = i2c_hid_finish_hwreset(ihid);
986 mutex_unlock(&ihid->reset_lock);
987 } else {
988 ret = i2c_hid_set_power(ihid, I2C_HID_PWR_ON);
989 }
990
991 if (ret)
992 return ret;
993
994 return hid_driver_reset_resume(hid);
995 }
996
997 /*
998 * Check that the device exists and parse the HID descriptor.
999 */
__i2c_hid_core_probe(struct i2c_hid * ihid)1000 static int __i2c_hid_core_probe(struct i2c_hid *ihid)
1001 {
1002 struct i2c_client *client = ihid->client;
1003 struct hid_device *hid = ihid->hid;
1004 int ret;
1005
1006 ret = i2c_hid_probe_address(ihid);
1007 if (ret < 0) {
1008 i2c_hid_dbg(ihid, "nothing at this address: %d\n", ret);
1009 return -ENXIO;
1010 }
1011
1012 ret = i2c_hid_fetch_hid_descriptor(ihid);
1013 if (ret < 0) {
1014 dev_err(&client->dev,
1015 "Failed to fetch the HID Descriptor\n");
1016 return ret;
1017 }
1018
1019 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1020 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1021 hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1022
1023 hid->initial_quirks |= i2c_hid_get_dmi_quirks(hid->vendor,
1024 hid->product);
1025
1026 snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
1027 client->name, (u16)hid->vendor, (u16)hid->product);
1028 strscpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1029
1030 ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1031
1032 return 0;
1033 }
1034
i2c_hid_core_register_hid(struct i2c_hid * ihid)1035 static int i2c_hid_core_register_hid(struct i2c_hid *ihid)
1036 {
1037 struct i2c_client *client = ihid->client;
1038 struct hid_device *hid = ihid->hid;
1039 int ret;
1040
1041 enable_irq(client->irq);
1042
1043 ret = hid_add_device(hid);
1044 if (ret) {
1045 if (ret != -ENODEV)
1046 hid_err(client, "can't add hid device: %d\n", ret);
1047 disable_irq(client->irq);
1048 return ret;
1049 }
1050
1051 return 0;
1052 }
1053
i2c_hid_core_probe_panel_follower(struct i2c_hid * ihid)1054 static int i2c_hid_core_probe_panel_follower(struct i2c_hid *ihid)
1055 {
1056 int ret;
1057
1058 ret = i2c_hid_core_power_up(ihid);
1059 if (ret)
1060 return ret;
1061
1062 ret = __i2c_hid_core_probe(ihid);
1063 if (ret)
1064 goto err_power_down;
1065
1066 ret = i2c_hid_core_register_hid(ihid);
1067 if (ret)
1068 goto err_power_down;
1069
1070 return 0;
1071
1072 err_power_down:
1073 i2c_hid_core_power_down(ihid);
1074
1075 return ret;
1076 }
1077
ihid_core_panel_prepare_work(struct work_struct * work)1078 static void ihid_core_panel_prepare_work(struct work_struct *work)
1079 {
1080 struct i2c_hid *ihid = container_of(work, struct i2c_hid,
1081 panel_follower_prepare_work);
1082 struct hid_device *hid = ihid->hid;
1083 int ret;
1084
1085 /*
1086 * hid->version is set on the first power up. If it's still zero then
1087 * this is the first power on so we should perform initial power up
1088 * steps.
1089 */
1090 if (!hid->version)
1091 ret = i2c_hid_core_probe_panel_follower(ihid);
1092 else
1093 ret = i2c_hid_core_resume(ihid);
1094
1095 if (ret)
1096 dev_warn(&ihid->client->dev, "Power on failed: %d\n", ret);
1097 else
1098 WRITE_ONCE(ihid->prepare_work_finished, true);
1099
1100 /*
1101 * The work APIs provide a number of memory ordering guarantees
1102 * including one that says that memory writes before schedule_work()
1103 * are always visible to the work function, but they don't appear to
1104 * guarantee that a write that happened in the work is visible after
1105 * cancel_work_sync(). We'll add a write memory barrier here to match
1106 * with i2c_hid_core_panel_unpreparing() to ensure that our write to
1107 * prepare_work_finished is visible there.
1108 */
1109 smp_wmb();
1110 }
1111
i2c_hid_core_panel_prepared(struct drm_panel_follower * follower)1112 static int i2c_hid_core_panel_prepared(struct drm_panel_follower *follower)
1113 {
1114 struct i2c_hid *ihid = container_of(follower, struct i2c_hid, panel_follower);
1115
1116 /*
1117 * Powering on a touchscreen can be a slow process. Queue the work to
1118 * the system workqueue so we don't block the panel's power up.
1119 */
1120 WRITE_ONCE(ihid->prepare_work_finished, false);
1121 schedule_work(&ihid->panel_follower_prepare_work);
1122
1123 return 0;
1124 }
1125
i2c_hid_core_panel_unpreparing(struct drm_panel_follower * follower)1126 static int i2c_hid_core_panel_unpreparing(struct drm_panel_follower *follower)
1127 {
1128 struct i2c_hid *ihid = container_of(follower, struct i2c_hid, panel_follower);
1129
1130 cancel_work_sync(&ihid->panel_follower_prepare_work);
1131
1132 /* Match with ihid_core_panel_prepare_work() */
1133 smp_rmb();
1134 if (!READ_ONCE(ihid->prepare_work_finished))
1135 return 0;
1136
1137 return i2c_hid_core_suspend(ihid, true);
1138 }
1139
1140 static const struct drm_panel_follower_funcs i2c_hid_core_panel_follower_funcs = {
1141 .panel_prepared = i2c_hid_core_panel_prepared,
1142 .panel_unpreparing = i2c_hid_core_panel_unpreparing,
1143 };
1144
i2c_hid_core_register_panel_follower(struct i2c_hid * ihid)1145 static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
1146 {
1147 struct device *dev = &ihid->client->dev;
1148 int ret;
1149
1150 ihid->panel_follower.funcs = &i2c_hid_core_panel_follower_funcs;
1151
1152 /*
1153 * If we're not in control of our own power up/power down then we can't
1154 * do the logic to manage wakeups. Give a warning if a user thought
1155 * that was possible then force the capability off.
1156 */
1157 if (device_can_wakeup(dev)) {
1158 dev_warn(dev, "Can't wakeup if following panel\n");
1159 device_set_wakeup_capable(dev, false);
1160 }
1161
1162 ret = drm_panel_add_follower(dev, &ihid->panel_follower);
1163 if (ret)
1164 return ret;
1165
1166 return 0;
1167 }
1168
i2c_hid_core_probe(struct i2c_client * client,struct i2chid_ops * ops,u16 hid_descriptor_address,u32 quirks)1169 int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
1170 u16 hid_descriptor_address, u32 quirks)
1171 {
1172 int ret;
1173 struct i2c_hid *ihid;
1174 struct hid_device *hid;
1175
1176 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
1177
1178 if (!client->irq) {
1179 dev_err(&client->dev,
1180 "HID over i2c has not been provided an Int IRQ\n");
1181 return -EINVAL;
1182 }
1183
1184 if (client->irq < 0) {
1185 if (client->irq != -EPROBE_DEFER)
1186 dev_err(&client->dev,
1187 "HID over i2c doesn't have a valid IRQ\n");
1188 return client->irq;
1189 }
1190
1191 ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL);
1192 if (!ihid)
1193 return -ENOMEM;
1194
1195 i2c_set_clientdata(client, ihid);
1196
1197 ihid->ops = ops;
1198 ihid->client = client;
1199 ihid->wHIDDescRegister = cpu_to_le16(hid_descriptor_address);
1200 ihid->is_panel_follower = drm_is_panel_follower(&client->dev);
1201
1202 init_waitqueue_head(&ihid->wait);
1203 mutex_init(&ihid->reset_lock);
1204 INIT_WORK(&ihid->panel_follower_prepare_work, ihid_core_panel_prepare_work);
1205
1206 /* we need to allocate the command buffer without knowing the maximum
1207 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1208 * real computation later. */
1209 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1210 if (ret < 0)
1211 return ret;
1212 device_enable_async_suspend(&client->dev);
1213
1214 hid = hid_allocate_device();
1215 if (IS_ERR(hid)) {
1216 ret = PTR_ERR(hid);
1217 goto err_free_buffers;
1218 }
1219
1220 ihid->hid = hid;
1221
1222 hid->driver_data = client;
1223 hid->ll_driver = &i2c_hid_ll_driver;
1224 hid->dev.parent = &client->dev;
1225 hid->bus = BUS_I2C;
1226 hid->initial_quirks = quirks;
1227
1228 /* Power on and probe unless device is a panel follower. */
1229 if (!ihid->is_panel_follower) {
1230 ret = i2c_hid_core_power_up(ihid);
1231 if (ret < 0)
1232 goto err_destroy_device;
1233
1234 ret = __i2c_hid_core_probe(ihid);
1235 if (ret < 0)
1236 goto err_power_down;
1237 }
1238
1239 ret = i2c_hid_init_irq(client);
1240 if (ret < 0)
1241 goto err_power_down;
1242
1243 /*
1244 * If we're a panel follower, we'll register when the panel turns on;
1245 * otherwise we do it right away.
1246 */
1247 if (ihid->is_panel_follower)
1248 ret = i2c_hid_core_register_panel_follower(ihid);
1249 else
1250 ret = i2c_hid_core_register_hid(ihid);
1251 if (ret)
1252 goto err_free_irq;
1253
1254 return 0;
1255
1256 err_free_irq:
1257 free_irq(client->irq, ihid);
1258 err_power_down:
1259 if (!ihid->is_panel_follower)
1260 i2c_hid_core_power_down(ihid);
1261 err_destroy_device:
1262 hid_destroy_device(hid);
1263 err_free_buffers:
1264 i2c_hid_free_buffers(ihid);
1265
1266 return ret;
1267 }
1268 EXPORT_SYMBOL_GPL(i2c_hid_core_probe);
1269
i2c_hid_core_remove(struct i2c_client * client)1270 void i2c_hid_core_remove(struct i2c_client *client)
1271 {
1272 struct i2c_hid *ihid = i2c_get_clientdata(client);
1273 struct hid_device *hid;
1274
1275 /*
1276 * If we're a follower, the act of unfollowing will cause us to be
1277 * powered down. Otherwise we need to manually do it.
1278 */
1279 if (ihid->is_panel_follower)
1280 drm_panel_remove_follower(&ihid->panel_follower);
1281 else
1282 i2c_hid_core_suspend(ihid, true);
1283
1284 hid = ihid->hid;
1285 hid_destroy_device(hid);
1286
1287 free_irq(client->irq, ihid);
1288
1289 if (ihid->bufsize)
1290 i2c_hid_free_buffers(ihid);
1291 }
1292 EXPORT_SYMBOL_GPL(i2c_hid_core_remove);
1293
i2c_hid_core_shutdown(struct i2c_client * client)1294 void i2c_hid_core_shutdown(struct i2c_client *client)
1295 {
1296 struct i2c_hid *ihid = i2c_get_clientdata(client);
1297
1298 i2c_hid_set_power(ihid, I2C_HID_PWR_SLEEP);
1299 free_irq(client->irq, ihid);
1300
1301 i2c_hid_core_shutdown_tail(ihid);
1302 }
1303 EXPORT_SYMBOL_GPL(i2c_hid_core_shutdown);
1304
i2c_hid_core_pm_suspend(struct device * dev)1305 static int i2c_hid_core_pm_suspend(struct device *dev)
1306 {
1307 struct i2c_client *client = to_i2c_client(dev);
1308 struct i2c_hid *ihid = i2c_get_clientdata(client);
1309
1310 if (ihid->is_panel_follower)
1311 return 0;
1312
1313 return i2c_hid_core_suspend(ihid, false);
1314 }
1315
i2c_hid_core_pm_resume(struct device * dev)1316 static int i2c_hid_core_pm_resume(struct device *dev)
1317 {
1318 struct i2c_client *client = to_i2c_client(dev);
1319 struct i2c_hid *ihid = i2c_get_clientdata(client);
1320
1321 if (ihid->is_panel_follower)
1322 return 0;
1323
1324 return i2c_hid_core_resume(ihid);
1325 }
1326
1327 const struct dev_pm_ops i2c_hid_core_pm = {
1328 SYSTEM_SLEEP_PM_OPS(i2c_hid_core_pm_suspend, i2c_hid_core_pm_resume)
1329 };
1330 EXPORT_SYMBOL_GPL(i2c_hid_core_pm);
1331
1332 MODULE_DESCRIPTION("HID over I2C core driver");
1333 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1334 MODULE_LICENSE("GPL");
1335