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 <linux/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 #define I2C_HID_QUIRK_DELAY_WAKEUP_AFTER_RESUME BIT(6)
54
55 /* Command opcodes */
56 #define I2C_HID_OPCODE_RESET 0x01
57 #define I2C_HID_OPCODE_GET_REPORT 0x02
58 #define I2C_HID_OPCODE_SET_REPORT 0x03
59 #define I2C_HID_OPCODE_GET_IDLE 0x04
60 #define I2C_HID_OPCODE_SET_IDLE 0x05
61 #define I2C_HID_OPCODE_GET_PROTOCOL 0x06
62 #define I2C_HID_OPCODE_SET_PROTOCOL 0x07
63 #define I2C_HID_OPCODE_SET_POWER 0x08
64
65 /* flags */
66 #define I2C_HID_STARTED 0
67 #define I2C_HID_RESET_PENDING 1
68
69 #define I2C_HID_PWR_ON 0x00
70 #define I2C_HID_PWR_SLEEP 0x01
71
72 #define i2c_hid_dbg(ihid, ...) dev_dbg(&(ihid)->client->dev, __VA_ARGS__)
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 /* The main device structure */
92 struct i2c_hid {
93 struct i2c_client *client; /* i2c client */
94 struct hid_device *hid; /* pointer to corresponding HID dev */
95 struct i2c_hid_desc hdesc; /* the HID Descriptor */
96 __le16 wHIDDescRegister; /* location of the i2c
97 * register of the HID
98 * descriptor. */
99 unsigned int bufsize; /* i2c buffer size */
100 u8 *inbuf; /* Input buffer */
101 u8 *rawbuf; /* Raw Input buffer */
102 u8 *cmdbuf; /* Command buffer */
103
104 unsigned long flags; /* device flags */
105 unsigned long quirks; /* Various quirks */
106
107 wait_queue_head_t wait; /* For waiting the interrupt */
108
109 struct mutex cmd_lock; /* protects cmdbuf and rawbuf */
110 struct mutex reset_lock;
111
112 struct i2chid_ops *ops;
113 struct drm_panel_follower panel_follower;
114 struct work_struct panel_follower_prepare_work;
115 bool is_panel_follower;
116 bool prepare_work_finished;
117 };
118
119 static const struct i2c_hid_quirks {
120 __u16 idVendor;
121 __u16 idProduct;
122 __u32 quirks;
123 } i2c_hid_quirks[] = {
124 { I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
125 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
126 { I2C_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_VOYO_WINPAD_A15,
127 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
128 { I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_3118,
129 I2C_HID_QUIRK_NO_IRQ_AFTER_RESET },
130 { USB_VENDOR_ID_ALPS_JP, HID_ANY_ID,
131 I2C_HID_QUIRK_RESET_ON_RESUME },
132 { I2C_VENDOR_ID_SYNAPTICS, I2C_PRODUCT_ID_SYNAPTICS_SYNA2393,
133 I2C_HID_QUIRK_RESET_ON_RESUME },
134 { USB_VENDOR_ID_ITE, I2C_DEVICE_ID_ITE_LENOVO_LEGION_Y720,
135 I2C_HID_QUIRK_BAD_INPUT_SIZE },
136 { I2C_VENDOR_ID_CIRQUE, I2C_PRODUCT_ID_CIRQUE_1063,
137 I2C_HID_QUIRK_NO_SLEEP_ON_SUSPEND },
138 /*
139 * Sending the wakeup after reset actually break ELAN touchscreen controller
140 */
141 { USB_VENDOR_ID_ELAN, HID_ANY_ID,
142 I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET |
143 I2C_HID_QUIRK_BOGUS_IRQ },
144 { I2C_VENDOR_ID_GOODIX, I2C_DEVICE_ID_GOODIX_0D42,
145 I2C_HID_QUIRK_DELAY_WAKEUP_AFTER_RESUME },
146 { 0, 0 }
147 };
148
149 /*
150 * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
151 * @idVendor: the 16-bit vendor ID
152 * @idProduct: the 16-bit product ID
153 *
154 * Returns: a u32 quirks value.
155 */
i2c_hid_lookup_quirk(const u16 idVendor,const u16 idProduct)156 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
157 {
158 u32 quirks = 0;
159 int n;
160
161 for (n = 0; i2c_hid_quirks[n].idVendor; n++)
162 if (i2c_hid_quirks[n].idVendor == idVendor &&
163 (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
164 i2c_hid_quirks[n].idProduct == idProduct))
165 quirks = i2c_hid_quirks[n].quirks;
166
167 return quirks;
168 }
169
i2c_hid_probe_address(struct i2c_hid * ihid)170 static int i2c_hid_probe_address(struct i2c_hid *ihid)
171 {
172 int ret;
173
174 /*
175 * Some STM-based devices need 400µs after a rising clock edge to wake
176 * from deep sleep, in which case the first read will fail. Try after a
177 * short sleep to see if the device came alive on the bus. Certain
178 * Weida Tech devices also need this.
179 */
180 ret = i2c_smbus_read_byte(ihid->client);
181 if (ret < 0) {
182 usleep_range(400, 500);
183 ret = i2c_smbus_read_byte(ihid->client);
184 }
185 return ret < 0 ? ret : 0;
186 }
187
i2c_hid_xfer(struct i2c_hid * ihid,u8 * send_buf,int send_len,u8 * recv_buf,int recv_len)188 static int i2c_hid_xfer(struct i2c_hid *ihid,
189 u8 *send_buf, int send_len, u8 *recv_buf, int recv_len)
190 {
191 struct i2c_client *client = ihid->client;
192 struct i2c_msg msgs[2] = { 0 };
193 int n = 0;
194 int ret;
195
196 if (send_len) {
197 i2c_hid_dbg(ihid, "%s: cmd=%*ph\n",
198 __func__, send_len, send_buf);
199
200 msgs[n].addr = client->addr;
201 msgs[n].flags = (client->flags & I2C_M_TEN) | I2C_M_DMA_SAFE;
202 msgs[n].len = send_len;
203 msgs[n].buf = send_buf;
204 n++;
205 }
206
207 if (recv_len) {
208 msgs[n].addr = client->addr;
209 msgs[n].flags = (client->flags & I2C_M_TEN) |
210 I2C_M_RD | I2C_M_DMA_SAFE;
211 msgs[n].len = recv_len;
212 msgs[n].buf = recv_buf;
213 n++;
214 }
215
216 ret = i2c_transfer(client->adapter, msgs, n);
217
218 if (ret != n)
219 return ret < 0 ? ret : -EIO;
220
221 return 0;
222 }
223
i2c_hid_read_register(struct i2c_hid * ihid,__le16 reg,void * buf,size_t len)224 static int i2c_hid_read_register(struct i2c_hid *ihid, __le16 reg,
225 void *buf, size_t len)
226 {
227 guard(mutex)(&ihid->cmd_lock);
228
229 *(__le16 *)ihid->cmdbuf = reg;
230
231 return i2c_hid_xfer(ihid, ihid->cmdbuf, sizeof(__le16), buf, len);
232 }
233
i2c_hid_encode_command(u8 * buf,u8 opcode,int report_type,int report_id)234 static size_t i2c_hid_encode_command(u8 *buf, u8 opcode,
235 int report_type, int report_id)
236 {
237 size_t length = 0;
238
239 if (report_id < 0x0F) {
240 buf[length++] = report_type << 4 | report_id;
241 buf[length++] = opcode;
242 } else {
243 buf[length++] = report_type << 4 | 0x0F;
244 buf[length++] = opcode;
245 buf[length++] = report_id;
246 }
247
248 return length;
249 }
250
i2c_hid_get_report(struct i2c_hid * ihid,u8 report_type,u8 report_id,u8 * recv_buf,size_t recv_len)251 static int i2c_hid_get_report(struct i2c_hid *ihid,
252 u8 report_type, u8 report_id,
253 u8 *recv_buf, size_t recv_len)
254 {
255 size_t length = 0;
256 size_t ret_count;
257 int error;
258
259 i2c_hid_dbg(ihid, "%s\n", __func__);
260
261 guard(mutex)(&ihid->cmd_lock);
262
263 /* Command register goes first */
264 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
265 length += sizeof(__le16);
266 /* Next is GET_REPORT command */
267 length += i2c_hid_encode_command(ihid->cmdbuf + length,
268 I2C_HID_OPCODE_GET_REPORT,
269 report_type, report_id);
270 /*
271 * Device will send report data through data register. Because
272 * command can be either 2 or 3 bytes destination for the data
273 * register may be not aligned.
274 */
275 put_unaligned_le16(le16_to_cpu(ihid->hdesc.wDataRegister),
276 ihid->cmdbuf + length);
277 length += sizeof(__le16);
278
279 /*
280 * In addition to report data device will supply data length
281 * in the first 2 bytes of the response, so adjust .
282 */
283 error = i2c_hid_xfer(ihid, ihid->cmdbuf, length,
284 ihid->rawbuf, recv_len + sizeof(__le16));
285 if (error) {
286 dev_err(&ihid->client->dev,
287 "failed to set a report to device: %d\n", error);
288 return error;
289 }
290
291 /* The buffer is sufficiently aligned */
292 ret_count = le16_to_cpup((__le16 *)ihid->rawbuf);
293
294 /* Check for empty report response */
295 if (ret_count <= sizeof(__le16))
296 return 0;
297
298 recv_len = min(recv_len, ret_count - sizeof(__le16));
299 memcpy(recv_buf, ihid->rawbuf + sizeof(__le16), recv_len);
300
301 if (report_id && recv_len != 0 && recv_buf[0] != report_id) {
302 dev_err(&ihid->client->dev,
303 "device returned incorrect report (%d vs %d expected)\n",
304 recv_buf[0], report_id);
305 return -EINVAL;
306 }
307
308 return recv_len;
309 }
310
i2c_hid_format_report(u8 * buf,int report_id,const u8 * data,size_t size)311 static size_t i2c_hid_format_report(u8 *buf, int report_id,
312 const u8 *data, size_t size)
313 {
314 size_t length = sizeof(__le16); /* reserve space to store size */
315
316 if (report_id)
317 buf[length++] = report_id;
318
319 memcpy(buf + length, data, size);
320 length += size;
321
322 /* Store overall size in the beginning of the buffer */
323 put_unaligned_le16(length, buf);
324
325 return length;
326 }
327
328 /**
329 * i2c_hid_set_or_send_report: forward an incoming report to the device
330 * @ihid: the i2c hid device
331 * @report_type: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
332 * @report_id: the report ID
333 * @buf: the actual data to transfer, without the report ID
334 * @data_len: size of buf
335 * @do_set: true: use SET_REPORT HID command, false: send plain OUTPUT report
336 */
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)337 static int i2c_hid_set_or_send_report(struct i2c_hid *ihid,
338 u8 report_type, u8 report_id,
339 const u8 *buf, size_t data_len,
340 bool do_set)
341 {
342 size_t length = 0;
343 int error;
344
345 i2c_hid_dbg(ihid, "%s\n", __func__);
346
347 if (data_len > ihid->bufsize)
348 return -EINVAL;
349
350 if (!do_set && le16_to_cpu(ihid->hdesc.wMaxOutputLength) == 0)
351 return -ENOSYS;
352
353 guard(mutex)(&ihid->cmd_lock);
354
355 if (do_set) {
356 /* Command register goes first */
357 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
358 length += sizeof(__le16);
359 /* Next is SET_REPORT command */
360 length += i2c_hid_encode_command(ihid->cmdbuf + length,
361 I2C_HID_OPCODE_SET_REPORT,
362 report_type, report_id);
363 /*
364 * Report data will go into the data register. Because
365 * command can be either 2 or 3 bytes destination for
366 * the data register may be not aligned.
367 */
368 put_unaligned_le16(le16_to_cpu(ihid->hdesc.wDataRegister),
369 ihid->cmdbuf + length);
370 length += sizeof(__le16);
371 } else {
372 /*
373 * With simple "send report" all data goes into the output
374 * register.
375 */
376 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wOutputRegister;
377 length += sizeof(__le16);
378 }
379
380 length += i2c_hid_format_report(ihid->cmdbuf + length,
381 report_id, buf, data_len);
382
383 error = i2c_hid_xfer(ihid, ihid->cmdbuf, length, NULL, 0);
384 if (error) {
385 dev_err(&ihid->client->dev,
386 "failed to set a report to device: %d\n", error);
387 return error;
388 }
389
390 return data_len;
391 }
392
i2c_hid_set_power_command(struct i2c_hid * ihid,int power_state)393 static int i2c_hid_set_power_command(struct i2c_hid *ihid, int power_state)
394 {
395 size_t length;
396
397 guard(mutex)(&ihid->cmd_lock);
398
399 /* SET_POWER uses command register */
400 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
401 length = sizeof(__le16);
402
403 /* Now the command itself */
404 length += i2c_hid_encode_command(ihid->cmdbuf + length,
405 I2C_HID_OPCODE_SET_POWER,
406 0, power_state);
407
408 return i2c_hid_xfer(ihid, ihid->cmdbuf, length, NULL, 0);
409 }
410
i2c_hid_set_power(struct i2c_hid * ihid,int power_state)411 static int i2c_hid_set_power(struct i2c_hid *ihid, int power_state)
412 {
413 int ret;
414
415 i2c_hid_dbg(ihid, "%s\n", __func__);
416
417 ret = i2c_hid_set_power_command(ihid, power_state);
418 if (ret)
419 dev_err(&ihid->client->dev,
420 "failed to change power setting.\n");
421
422 /*
423 * The HID over I2C specification states that if a DEVICE needs time
424 * after the PWR_ON request, it should utilise CLOCK stretching.
425 * However, it has been observered that the Windows driver provides a
426 * 1ms sleep between the PWR_ON and RESET requests.
427 * According to Goodix Windows even waits 60 ms after (other?)
428 * PWR_ON requests. Testing has confirmed that several devices
429 * will not work properly without a delay after a PWR_ON request.
430 */
431 if (!ret && power_state == I2C_HID_PWR_ON)
432 msleep(60);
433
434 return ret;
435 }
436
i2c_hid_start_hwreset(struct i2c_hid * ihid)437 static int i2c_hid_start_hwreset(struct i2c_hid *ihid)
438 {
439 size_t length = 0;
440 int ret;
441
442 i2c_hid_dbg(ihid, "%s\n", __func__);
443
444 /*
445 * This prevents sending feature reports while the device is
446 * being reset. Otherwise we may lose the reset complete
447 * interrupt.
448 */
449 lockdep_assert_held(&ihid->reset_lock);
450
451 ret = i2c_hid_set_power(ihid, I2C_HID_PWR_ON);
452 if (ret)
453 return ret;
454
455 scoped_guard(mutex, &ihid->cmd_lock) {
456 /* Prepare reset command. Command register goes first. */
457 *(__le16 *)ihid->cmdbuf = ihid->hdesc.wCommandRegister;
458 length += sizeof(__le16);
459 /* Next is RESET command itself */
460 length += i2c_hid_encode_command(ihid->cmdbuf + length,
461 I2C_HID_OPCODE_RESET, 0, 0);
462
463 set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
464
465 ret = i2c_hid_xfer(ihid, ihid->cmdbuf, length, NULL, 0);
466 if (ret) {
467 dev_err(&ihid->client->dev,
468 "failed to reset device: %d\n", ret);
469 break;
470 }
471
472 return 0;
473 }
474
475 /* Clean up if sending reset command failed */
476 clear_bit(I2C_HID_RESET_PENDING, &ihid->flags);
477 i2c_hid_set_power(ihid, I2C_HID_PWR_SLEEP);
478 return ret;
479 }
480
i2c_hid_finish_hwreset(struct i2c_hid * ihid)481 static int i2c_hid_finish_hwreset(struct i2c_hid *ihid)
482 {
483 int ret = 0;
484
485 i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
486
487 if (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET) {
488 msleep(100);
489 clear_bit(I2C_HID_RESET_PENDING, &ihid->flags);
490 } else if (!wait_event_timeout(ihid->wait,
491 !test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
492 msecs_to_jiffies(1000))) {
493 dev_warn(&ihid->client->dev, "device did not ack reset within 1000 ms\n");
494 clear_bit(I2C_HID_RESET_PENDING, &ihid->flags);
495 }
496 i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
497
498 /* At least some SIS devices need this after reset */
499 if (!(ihid->quirks & I2C_HID_QUIRK_NO_WAKEUP_AFTER_RESET))
500 ret = i2c_hid_set_power(ihid, I2C_HID_PWR_ON);
501
502 return ret;
503 }
504
i2c_hid_get_input(struct i2c_hid * ihid)505 static void i2c_hid_get_input(struct i2c_hid *ihid)
506 {
507 u16 size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
508 u16 ret_size;
509 int ret;
510
511 if (size > ihid->bufsize)
512 size = ihid->bufsize;
513
514 ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
515 if (ret != size) {
516 if (ret < 0)
517 return;
518
519 dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
520 __func__, ret, size);
521 return;
522 }
523
524 /* Receiving buffer is properly aligned */
525 ret_size = le16_to_cpup((__le16 *)ihid->inbuf);
526 if (!ret_size) {
527 /* host or device initiated RESET completed */
528 if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
529 wake_up(&ihid->wait);
530 return;
531 }
532
533 if ((ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ) && ret_size == 0xffff) {
534 dev_warn_once(&ihid->client->dev,
535 "%s: IRQ triggered but there's no data\n",
536 __func__);
537 return;
538 }
539
540 if (ret_size > size || ret_size < sizeof(__le16)) {
541 if (ihid->quirks & I2C_HID_QUIRK_BAD_INPUT_SIZE) {
542 *(__le16 *)ihid->inbuf = cpu_to_le16(size);
543 ret_size = size;
544 } else {
545 dev_err(&ihid->client->dev,
546 "%s: incomplete report (%d/%d)\n",
547 __func__, size, ret_size);
548 return;
549 }
550 }
551
552 i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
553
554 if (test_bit(I2C_HID_STARTED, &ihid->flags)) {
555 if (ihid->hid->group != HID_GROUP_RMI)
556 pm_wakeup_event(&ihid->client->dev, 0);
557
558 hid_input_report(ihid->hid, HID_INPUT_REPORT,
559 ihid->inbuf + sizeof(__le16),
560 ret_size - sizeof(__le16), 1);
561 }
562
563 return;
564 }
565
i2c_hid_irq(int irq,void * dev_id)566 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
567 {
568 struct i2c_hid *ihid = dev_id;
569
570 i2c_hid_get_input(ihid);
571
572 return IRQ_HANDLED;
573 }
574
i2c_hid_get_report_length(struct hid_report * report)575 static int i2c_hid_get_report_length(struct hid_report *report)
576 {
577 return ((report->size - 1) >> 3) + 1 +
578 report->device->report_enum[report->type].numbered + 2;
579 }
580
581 /*
582 * Traverse the supplied list of reports and find the longest
583 */
i2c_hid_find_max_report(struct hid_device * hid,unsigned int type,unsigned int * max)584 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
585 unsigned int *max)
586 {
587 struct hid_report *report;
588 unsigned int size;
589
590 /* We should not rely on wMaxInputLength, as some devices may set it to
591 * a wrong length. */
592 list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
593 size = i2c_hid_get_report_length(report);
594 if (*max < size)
595 *max = size;
596 }
597 }
598
i2c_hid_free_buffers(struct i2c_hid * ihid)599 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
600 {
601 kfree(ihid->inbuf);
602 kfree(ihid->rawbuf);
603 kfree(ihid->cmdbuf);
604 ihid->inbuf = NULL;
605 ihid->rawbuf = NULL;
606 ihid->cmdbuf = NULL;
607 ihid->bufsize = 0;
608 }
609
i2c_hid_alloc_buffers(struct i2c_hid * ihid,size_t report_size)610 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
611 {
612 /*
613 * The worst case is computed from the set_report command with a
614 * reportID > 15 and the maximum report length.
615 */
616 int cmd_len = sizeof(__le16) + /* command register */
617 sizeof(u8) + /* encoded report type/ID */
618 sizeof(u8) + /* opcode */
619 sizeof(u8) + /* optional 3rd byte report ID */
620 sizeof(__le16) + /* data register */
621 sizeof(__le16) + /* report data size */
622 sizeof(u8) + /* report ID if numbered report */
623 report_size;
624
625 ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
626 ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
627 ihid->cmdbuf = kzalloc(cmd_len, GFP_KERNEL);
628
629 if (!ihid->inbuf || !ihid->rawbuf || !ihid->cmdbuf) {
630 i2c_hid_free_buffers(ihid);
631 return -ENOMEM;
632 }
633
634 ihid->bufsize = report_size;
635
636 return 0;
637 }
638
i2c_hid_get_raw_report(struct hid_device * hid,u8 report_type,u8 report_id,u8 * buf,size_t count)639 static int i2c_hid_get_raw_report(struct hid_device *hid,
640 u8 report_type, u8 report_id,
641 u8 *buf, size_t count)
642 {
643 struct i2c_client *client = hid->driver_data;
644 struct i2c_hid *ihid = i2c_get_clientdata(client);
645 int ret_count;
646
647 if (report_type == HID_OUTPUT_REPORT)
648 return -EINVAL;
649
650 /*
651 * In case of unnumbered reports the response from the device will
652 * not have the report ID that the upper layers expect, so we need
653 * to stash it the buffer ourselves and adjust the data size.
654 */
655 if (!report_id) {
656 buf[0] = 0;
657 buf++;
658 count--;
659 }
660
661 ret_count = i2c_hid_get_report(ihid,
662 report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
663 report_id, buf, count);
664
665 if (ret_count > 0 && !report_id)
666 ret_count++;
667
668 return ret_count;
669 }
670
i2c_hid_output_raw_report(struct hid_device * hid,u8 report_type,const u8 * buf,size_t count,bool do_set)671 static int i2c_hid_output_raw_report(struct hid_device *hid, u8 report_type,
672 const u8 *buf, size_t count, bool do_set)
673 {
674 struct i2c_client *client = hid->driver_data;
675 struct i2c_hid *ihid = i2c_get_clientdata(client);
676 int report_id = buf[0];
677 int ret;
678
679 if (report_type == HID_INPUT_REPORT)
680 return -EINVAL;
681
682 mutex_lock(&ihid->reset_lock);
683
684 /*
685 * Note that both numbered and unnumbered reports passed here
686 * are supposed to have report ID stored in the 1st byte of the
687 * buffer, so we strip it off unconditionally before passing payload
688 * to i2c_hid_set_or_send_report which takes care of encoding
689 * everything properly.
690 */
691 ret = i2c_hid_set_or_send_report(ihid,
692 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
693 report_id, buf + 1, count - 1, do_set);
694
695 if (ret >= 0)
696 ret++; /* add report_id to the number of transferred bytes */
697
698 mutex_unlock(&ihid->reset_lock);
699
700 return ret;
701 }
702
i2c_hid_output_report(struct hid_device * hid,u8 * buf,size_t count)703 static int i2c_hid_output_report(struct hid_device *hid, u8 *buf, size_t count)
704 {
705 return i2c_hid_output_raw_report(hid, HID_OUTPUT_REPORT, buf, count,
706 false);
707 }
708
i2c_hid_raw_request(struct hid_device * hid,unsigned char reportnum,__u8 * buf,size_t len,unsigned char rtype,int reqtype)709 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
710 __u8 *buf, size_t len, unsigned char rtype,
711 int reqtype)
712 {
713 switch (reqtype) {
714 case HID_REQ_GET_REPORT:
715 return i2c_hid_get_raw_report(hid, rtype, reportnum, buf, len);
716 case HID_REQ_SET_REPORT:
717 if (buf[0] != reportnum)
718 return -EINVAL;
719 return i2c_hid_output_raw_report(hid, rtype, buf, len, true);
720 default:
721 return -EIO;
722 }
723 }
724
i2c_hid_parse(struct hid_device * hid)725 static int i2c_hid_parse(struct hid_device *hid)
726 {
727 struct i2c_client *client = hid->driver_data;
728 struct i2c_hid *ihid = i2c_get_clientdata(client);
729 struct i2c_hid_desc *hdesc = &ihid->hdesc;
730 char *rdesc = NULL, *use_override = NULL;
731 unsigned int rsize;
732 int ret;
733 int tries = 3;
734
735 i2c_hid_dbg(ihid, "entering %s\n", __func__);
736
737 rsize = le16_to_cpu(hdesc->wReportDescLength);
738 if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
739 dbg_hid("weird size of report descriptor (%u)\n", rsize);
740 return -EINVAL;
741 }
742
743 mutex_lock(&ihid->reset_lock);
744 do {
745 ret = i2c_hid_start_hwreset(ihid);
746 if (ret == 0)
747 ret = i2c_hid_finish_hwreset(ihid);
748 else
749 msleep(1000);
750 } while (tries-- > 0 && ret);
751 mutex_unlock(&ihid->reset_lock);
752
753 if (ret)
754 return ret;
755
756 use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name,
757 &rsize);
758
759 if (use_override) {
760 rdesc = use_override;
761 i2c_hid_dbg(ihid, "Using a HID report descriptor override\n");
762 } else {
763 rdesc = kzalloc(rsize, GFP_KERNEL);
764 if (!rdesc)
765 return -ENOMEM;
766
767 i2c_hid_dbg(ihid, "asking HID report descriptor\n");
768
769 ret = i2c_hid_read_register(ihid,
770 ihid->hdesc.wReportDescRegister,
771 rdesc, rsize);
772 if (ret) {
773 hid_err(hid, "reading report descriptor failed\n");
774 goto out;
775 }
776 }
777
778 i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
779
780 ret = hid_parse_report(hid, rdesc, rsize);
781 if (ret)
782 dbg_hid("parsing report descriptor failed\n");
783
784 out:
785 if (!use_override)
786 kfree(rdesc);
787
788 return ret;
789 }
790
i2c_hid_start(struct hid_device * hid)791 static int i2c_hid_start(struct hid_device *hid)
792 {
793 struct i2c_client *client = hid->driver_data;
794 struct i2c_hid *ihid = i2c_get_clientdata(client);
795 int ret;
796 unsigned int bufsize = HID_MIN_BUFFER_SIZE;
797
798 i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
799 i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
800 i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
801
802 if (bufsize > ihid->bufsize) {
803 disable_irq(client->irq);
804 i2c_hid_free_buffers(ihid);
805
806 ret = i2c_hid_alloc_buffers(ihid, bufsize);
807 enable_irq(client->irq);
808
809 if (ret)
810 return ret;
811 }
812
813 return 0;
814 }
815
i2c_hid_stop(struct hid_device * hid)816 static void i2c_hid_stop(struct hid_device *hid)
817 {
818 hid->claimed = 0;
819 }
820
i2c_hid_open(struct hid_device * hid)821 static int i2c_hid_open(struct hid_device *hid)
822 {
823 struct i2c_client *client = hid->driver_data;
824 struct i2c_hid *ihid = i2c_get_clientdata(client);
825
826 set_bit(I2C_HID_STARTED, &ihid->flags);
827 return 0;
828 }
829
i2c_hid_close(struct hid_device * hid)830 static void i2c_hid_close(struct hid_device *hid)
831 {
832 struct i2c_client *client = hid->driver_data;
833 struct i2c_hid *ihid = i2c_get_clientdata(client);
834
835 clear_bit(I2C_HID_STARTED, &ihid->flags);
836 }
837
838 static const struct hid_ll_driver i2c_hid_ll_driver = {
839 .parse = i2c_hid_parse,
840 .start = i2c_hid_start,
841 .stop = i2c_hid_stop,
842 .open = i2c_hid_open,
843 .close = i2c_hid_close,
844 .output_report = i2c_hid_output_report,
845 .raw_request = i2c_hid_raw_request,
846 };
847
i2c_hid_init_irq(struct i2c_client * client)848 static int i2c_hid_init_irq(struct i2c_client *client)
849 {
850 struct i2c_hid *ihid = i2c_get_clientdata(client);
851 unsigned long irqflags = 0;
852 int ret;
853
854 i2c_hid_dbg(ihid, "Requesting IRQ: %d\n", client->irq);
855
856 if (!irq_get_trigger_type(client->irq))
857 irqflags = IRQF_TRIGGER_LOW;
858
859 ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
860 irqflags | IRQF_ONESHOT | IRQF_NO_AUTOEN,
861 client->name, ihid);
862 if (ret < 0) {
863 dev_warn(&client->dev,
864 "Could not register for %s interrupt, irq = %d,"
865 " ret = %d\n",
866 client->name, client->irq, ret);
867
868 return ret;
869 }
870
871 return 0;
872 }
873
i2c_hid_fetch_hid_descriptor(struct i2c_hid * ihid)874 static int i2c_hid_fetch_hid_descriptor(struct i2c_hid *ihid)
875 {
876 struct i2c_client *client = ihid->client;
877 struct i2c_hid_desc *hdesc = &ihid->hdesc;
878 unsigned int dsize;
879 int error;
880
881 /* i2c hid fetch using a fixed descriptor size (30 bytes) */
882 if (i2c_hid_get_dmi_i2c_hid_desc_override(client->name)) {
883 i2c_hid_dbg(ihid, "Using a HID descriptor override\n");
884 ihid->hdesc =
885 *i2c_hid_get_dmi_i2c_hid_desc_override(client->name);
886 } else {
887 i2c_hid_dbg(ihid, "Fetching the HID descriptor\n");
888 error = i2c_hid_read_register(ihid,
889 ihid->wHIDDescRegister,
890 &ihid->hdesc,
891 sizeof(ihid->hdesc));
892 if (error) {
893 dev_err(&ihid->client->dev,
894 "failed to fetch HID descriptor: %d\n",
895 error);
896 return -ENODEV;
897 }
898 }
899
900 /* Validate the length of HID descriptor, the 4 first bytes:
901 * bytes 0-1 -> length
902 * bytes 2-3 -> bcdVersion (has to be 1.00) */
903 /* check bcdVersion == 1.0 */
904 if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
905 dev_err(&ihid->client->dev,
906 "unexpected HID descriptor bcdVersion (0x%04hx)\n",
907 le16_to_cpu(hdesc->bcdVersion));
908 return -ENODEV;
909 }
910
911 /* Descriptor length should be 30 bytes as per the specification */
912 dsize = le16_to_cpu(hdesc->wHIDDescLength);
913 if (dsize != sizeof(struct i2c_hid_desc)) {
914 dev_err(&ihid->client->dev,
915 "weird size of HID descriptor (%u)\n", dsize);
916 return -ENODEV;
917 }
918 i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, &ihid->hdesc);
919 return 0;
920 }
921
i2c_hid_core_power_up(struct i2c_hid * ihid)922 static int i2c_hid_core_power_up(struct i2c_hid *ihid)
923 {
924 if (!ihid->ops->power_up)
925 return 0;
926
927 return ihid->ops->power_up(ihid->ops);
928 }
929
i2c_hid_core_power_down(struct i2c_hid * ihid)930 static void i2c_hid_core_power_down(struct i2c_hid *ihid)
931 {
932 if (!ihid->ops->power_down)
933 return;
934
935 ihid->ops->power_down(ihid->ops);
936 }
937
i2c_hid_core_shutdown_tail(struct i2c_hid * ihid)938 static void i2c_hid_core_shutdown_tail(struct i2c_hid *ihid)
939 {
940 if (!ihid->ops->shutdown_tail)
941 return;
942
943 ihid->ops->shutdown_tail(ihid->ops);
944 }
945
i2c_hid_core_suspend(struct i2c_hid * ihid,bool force_poweroff)946 static int i2c_hid_core_suspend(struct i2c_hid *ihid, bool force_poweroff)
947 {
948 struct i2c_client *client = ihid->client;
949 struct hid_device *hid = ihid->hid;
950 int ret;
951
952 ret = hid_driver_suspend(hid, PMSG_SUSPEND);
953 if (ret < 0)
954 return ret;
955
956 /* Save some power */
957 if (!(ihid->quirks & I2C_HID_QUIRK_NO_SLEEP_ON_SUSPEND))
958 i2c_hid_set_power(ihid, I2C_HID_PWR_SLEEP);
959
960 disable_irq(client->irq);
961
962 if (force_poweroff || !device_may_wakeup(&client->dev))
963 i2c_hid_core_power_down(ihid);
964
965 return 0;
966 }
967
i2c_hid_core_resume(struct i2c_hid * ihid)968 static int i2c_hid_core_resume(struct i2c_hid *ihid)
969 {
970 struct i2c_client *client = ihid->client;
971 struct hid_device *hid = ihid->hid;
972 int ret;
973
974 if (!device_may_wakeup(&client->dev))
975 i2c_hid_core_power_up(ihid);
976
977 enable_irq(client->irq);
978
979 /* Make sure the device is awake on the bus */
980 ret = i2c_hid_probe_address(ihid);
981 if (ret < 0) {
982 dev_err(&client->dev, "nothing at address after resume: %d\n",
983 ret);
984 return -ENXIO;
985 }
986
987 /* On Goodix 27c6:0d42 wait extra time before device wakeup.
988 * It's not clear why but if we send wakeup too early, the device will
989 * never trigger input interrupts.
990 */
991 if (ihid->quirks & I2C_HID_QUIRK_DELAY_WAKEUP_AFTER_RESUME)
992 msleep(1500);
993
994 /* Instead of resetting device, simply powers the device on. This
995 * solves "incomplete reports" on Raydium devices 2386:3118 and
996 * 2386:4B33 and fixes various SIS touchscreens no longer sending
997 * data after a suspend/resume.
998 *
999 * However some ALPS touchpads generate IRQ storm without reset, so
1000 * let's still reset them here.
1001 */
1002 if (ihid->quirks & I2C_HID_QUIRK_RESET_ON_RESUME) {
1003 mutex_lock(&ihid->reset_lock);
1004 ret = i2c_hid_start_hwreset(ihid);
1005 if (ret == 0)
1006 ret = i2c_hid_finish_hwreset(ihid);
1007 mutex_unlock(&ihid->reset_lock);
1008 } else {
1009 ret = i2c_hid_set_power(ihid, I2C_HID_PWR_ON);
1010 }
1011
1012 if (ret)
1013 return ret;
1014
1015 return hid_driver_reset_resume(hid);
1016 }
1017
1018 /*
1019 * Check that the device exists and parse the HID descriptor.
1020 */
__i2c_hid_core_probe(struct i2c_hid * ihid)1021 static int __i2c_hid_core_probe(struct i2c_hid *ihid)
1022 {
1023 struct i2c_client *client = ihid->client;
1024 struct hid_device *hid = ihid->hid;
1025 int ret;
1026
1027 ret = i2c_hid_probe_address(ihid);
1028 if (ret < 0) {
1029 i2c_hid_dbg(ihid, "nothing at this address: %d\n", ret);
1030 return -ENXIO;
1031 }
1032
1033 ret = i2c_hid_fetch_hid_descriptor(ihid);
1034 if (ret < 0) {
1035 dev_err(&client->dev,
1036 "Failed to fetch the HID Descriptor\n");
1037 return ret;
1038 }
1039
1040 hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1041 hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1042 hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1043
1044 hid->initial_quirks |= i2c_hid_get_dmi_quirks(hid->vendor,
1045 hid->product);
1046
1047 snprintf(hid->name, sizeof(hid->name), "%s %04X:%04X",
1048 client->name, (u16)hid->vendor, (u16)hid->product);
1049 strscpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1050
1051 ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1052
1053 return 0;
1054 }
1055
i2c_hid_core_register_hid(struct i2c_hid * ihid)1056 static int i2c_hid_core_register_hid(struct i2c_hid *ihid)
1057 {
1058 struct i2c_client *client = ihid->client;
1059 struct hid_device *hid = ihid->hid;
1060 int ret;
1061
1062 enable_irq(client->irq);
1063
1064 ret = hid_add_device(hid);
1065 if (ret) {
1066 if (ret != -ENODEV)
1067 hid_err(client, "can't add hid device: %d\n", ret);
1068 disable_irq(client->irq);
1069 return ret;
1070 }
1071
1072 return 0;
1073 }
1074
i2c_hid_core_probe_panel_follower(struct i2c_hid * ihid)1075 static int i2c_hid_core_probe_panel_follower(struct i2c_hid *ihid)
1076 {
1077 int ret;
1078
1079 ret = i2c_hid_core_power_up(ihid);
1080 if (ret)
1081 return ret;
1082
1083 ret = __i2c_hid_core_probe(ihid);
1084 if (ret)
1085 goto err_power_down;
1086
1087 ret = i2c_hid_core_register_hid(ihid);
1088 if (ret)
1089 goto err_power_down;
1090
1091 return 0;
1092
1093 err_power_down:
1094 i2c_hid_core_power_down(ihid);
1095
1096 return ret;
1097 }
1098
ihid_core_panel_prepare_work(struct work_struct * work)1099 static void ihid_core_panel_prepare_work(struct work_struct *work)
1100 {
1101 struct i2c_hid *ihid = container_of(work, struct i2c_hid,
1102 panel_follower_prepare_work);
1103 struct hid_device *hid = ihid->hid;
1104 int ret;
1105
1106 /*
1107 * hid->version is set on the first power up. If it's still zero then
1108 * this is the first power on so we should perform initial power up
1109 * steps.
1110 */
1111 if (!hid->version)
1112 ret = i2c_hid_core_probe_panel_follower(ihid);
1113 else
1114 ret = i2c_hid_core_resume(ihid);
1115
1116 if (ret)
1117 dev_warn(&ihid->client->dev, "Power on failed: %d\n", ret);
1118 else
1119 WRITE_ONCE(ihid->prepare_work_finished, true);
1120
1121 /*
1122 * The work APIs provide a number of memory ordering guarantees
1123 * including one that says that memory writes before schedule_work()
1124 * are always visible to the work function, but they don't appear to
1125 * guarantee that a write that happened in the work is visible after
1126 * cancel_work_sync(). We'll add a write memory barrier here to match
1127 * with i2c_hid_core_panel_unpreparing() to ensure that our write to
1128 * prepare_work_finished is visible there.
1129 */
1130 smp_wmb();
1131 }
1132
i2c_hid_core_panel_prepared(struct drm_panel_follower * follower)1133 static int i2c_hid_core_panel_prepared(struct drm_panel_follower *follower)
1134 {
1135 struct i2c_hid *ihid = container_of(follower, struct i2c_hid, panel_follower);
1136
1137 /*
1138 * Powering on a touchscreen can be a slow process. Queue the work to
1139 * the system workqueue so we don't block the panel's power up.
1140 */
1141 WRITE_ONCE(ihid->prepare_work_finished, false);
1142 schedule_work(&ihid->panel_follower_prepare_work);
1143
1144 return 0;
1145 }
1146
i2c_hid_core_panel_unpreparing(struct drm_panel_follower * follower)1147 static int i2c_hid_core_panel_unpreparing(struct drm_panel_follower *follower)
1148 {
1149 struct i2c_hid *ihid = container_of(follower, struct i2c_hid, panel_follower);
1150
1151 cancel_work_sync(&ihid->panel_follower_prepare_work);
1152
1153 /* Match with ihid_core_panel_prepare_work() */
1154 smp_rmb();
1155 if (!READ_ONCE(ihid->prepare_work_finished))
1156 return 0;
1157
1158 return i2c_hid_core_suspend(ihid, true);
1159 }
1160
1161 static const struct drm_panel_follower_funcs i2c_hid_core_panel_follower_funcs = {
1162 .panel_prepared = i2c_hid_core_panel_prepared,
1163 .panel_unpreparing = i2c_hid_core_panel_unpreparing,
1164 };
1165
i2c_hid_core_register_panel_follower(struct i2c_hid * ihid)1166 static int i2c_hid_core_register_panel_follower(struct i2c_hid *ihid)
1167 {
1168 struct device *dev = &ihid->client->dev;
1169 int ret;
1170
1171 ihid->panel_follower.funcs = &i2c_hid_core_panel_follower_funcs;
1172
1173 /*
1174 * If we're not in control of our own power up/power down then we can't
1175 * do the logic to manage wakeups. Give a warning if a user thought
1176 * that was possible then force the capability off.
1177 */
1178 if (device_can_wakeup(dev)) {
1179 dev_warn(dev, "Can't wakeup if following panel\n");
1180 device_set_wakeup_capable(dev, false);
1181 }
1182
1183 ret = drm_panel_add_follower(dev, &ihid->panel_follower);
1184 if (ret)
1185 return ret;
1186
1187 return 0;
1188 }
1189
i2c_hid_core_probe(struct i2c_client * client,struct i2chid_ops * ops,u16 hid_descriptor_address,u32 quirks)1190 int i2c_hid_core_probe(struct i2c_client *client, struct i2chid_ops *ops,
1191 u16 hid_descriptor_address, u32 quirks)
1192 {
1193 int ret;
1194 struct i2c_hid *ihid;
1195 struct hid_device *hid;
1196
1197 dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
1198
1199 if (!client->irq) {
1200 dev_err(&client->dev,
1201 "HID over i2c has not been provided an Int IRQ\n");
1202 return -EINVAL;
1203 }
1204
1205 if (client->irq < 0) {
1206 if (client->irq != -EPROBE_DEFER)
1207 dev_err(&client->dev,
1208 "HID over i2c doesn't have a valid IRQ\n");
1209 return client->irq;
1210 }
1211
1212 ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL);
1213 if (!ihid)
1214 return -ENOMEM;
1215
1216 i2c_set_clientdata(client, ihid);
1217
1218 ihid->ops = ops;
1219 ihid->client = client;
1220 ihid->wHIDDescRegister = cpu_to_le16(hid_descriptor_address);
1221 ihid->is_panel_follower = drm_is_panel_follower(&client->dev);
1222
1223 init_waitqueue_head(&ihid->wait);
1224 mutex_init(&ihid->cmd_lock);
1225 mutex_init(&ihid->reset_lock);
1226 INIT_WORK(&ihid->panel_follower_prepare_work, ihid_core_panel_prepare_work);
1227
1228 /* we need to allocate the command buffer without knowing the maximum
1229 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1230 * real computation later. */
1231 ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1232 if (ret < 0)
1233 return ret;
1234 device_enable_async_suspend(&client->dev);
1235
1236 hid = hid_allocate_device();
1237 if (IS_ERR(hid)) {
1238 ret = PTR_ERR(hid);
1239 goto err_free_buffers;
1240 }
1241
1242 ihid->hid = hid;
1243
1244 hid->driver_data = client;
1245 hid->ll_driver = &i2c_hid_ll_driver;
1246 hid->dev.parent = &client->dev;
1247 hid->bus = BUS_I2C;
1248 hid->initial_quirks = quirks;
1249
1250 /* Power on and probe unless device is a panel follower. */
1251 if (!ihid->is_panel_follower) {
1252 ret = i2c_hid_core_power_up(ihid);
1253 if (ret < 0)
1254 goto err_destroy_device;
1255
1256 ret = __i2c_hid_core_probe(ihid);
1257 if (ret < 0)
1258 goto err_power_down;
1259 }
1260
1261 ret = i2c_hid_init_irq(client);
1262 if (ret < 0)
1263 goto err_power_down;
1264
1265 /*
1266 * If we're a panel follower, we'll register when the panel turns on;
1267 * otherwise we do it right away.
1268 */
1269 if (ihid->is_panel_follower)
1270 ret = i2c_hid_core_register_panel_follower(ihid);
1271 else
1272 ret = i2c_hid_core_register_hid(ihid);
1273 if (ret)
1274 goto err_free_irq;
1275
1276 return 0;
1277
1278 err_free_irq:
1279 free_irq(client->irq, ihid);
1280 err_power_down:
1281 if (!ihid->is_panel_follower)
1282 i2c_hid_core_power_down(ihid);
1283 err_destroy_device:
1284 hid_destroy_device(hid);
1285 err_free_buffers:
1286 i2c_hid_free_buffers(ihid);
1287
1288 return ret;
1289 }
1290 EXPORT_SYMBOL_GPL(i2c_hid_core_probe);
1291
i2c_hid_core_remove(struct i2c_client * client)1292 void i2c_hid_core_remove(struct i2c_client *client)
1293 {
1294 struct i2c_hid *ihid = i2c_get_clientdata(client);
1295 struct hid_device *hid;
1296
1297 /*
1298 * If we're a follower, the act of unfollowing will cause us to be
1299 * powered down. Otherwise we need to manually do it.
1300 */
1301 if (ihid->is_panel_follower)
1302 drm_panel_remove_follower(&ihid->panel_follower);
1303 else
1304 i2c_hid_core_suspend(ihid, true);
1305
1306 hid = ihid->hid;
1307 hid_destroy_device(hid);
1308
1309 free_irq(client->irq, ihid);
1310
1311 if (ihid->bufsize)
1312 i2c_hid_free_buffers(ihid);
1313 }
1314 EXPORT_SYMBOL_GPL(i2c_hid_core_remove);
1315
i2c_hid_core_shutdown(struct i2c_client * client)1316 void i2c_hid_core_shutdown(struct i2c_client *client)
1317 {
1318 struct i2c_hid *ihid = i2c_get_clientdata(client);
1319
1320 i2c_hid_set_power(ihid, I2C_HID_PWR_SLEEP);
1321 free_irq(client->irq, ihid);
1322
1323 i2c_hid_core_shutdown_tail(ihid);
1324 }
1325 EXPORT_SYMBOL_GPL(i2c_hid_core_shutdown);
1326
i2c_hid_core_pm_suspend(struct device * dev)1327 static int i2c_hid_core_pm_suspend(struct device *dev)
1328 {
1329 struct i2c_client *client = to_i2c_client(dev);
1330 struct i2c_hid *ihid = i2c_get_clientdata(client);
1331
1332 if (ihid->is_panel_follower)
1333 return 0;
1334
1335 return i2c_hid_core_suspend(ihid, false);
1336 }
1337
i2c_hid_core_pm_resume(struct device * dev)1338 static int i2c_hid_core_pm_resume(struct device *dev)
1339 {
1340 struct i2c_client *client = to_i2c_client(dev);
1341 struct i2c_hid *ihid = i2c_get_clientdata(client);
1342
1343 if (ihid->is_panel_follower)
1344 return 0;
1345
1346 return i2c_hid_core_resume(ihid);
1347 }
1348
1349 const struct dev_pm_ops i2c_hid_core_pm = {
1350 SYSTEM_SLEEP_PM_OPS(i2c_hid_core_pm_suspend, i2c_hid_core_pm_resume)
1351 };
1352 EXPORT_SYMBOL_GPL(i2c_hid_core_pm);
1353
1354 MODULE_DESCRIPTION("HID over I2C core driver");
1355 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1356 MODULE_LICENSE("GPL");
1357