1 /*
2  * HID over I2C protocol implementation
3  *
4  * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
5  * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
6  * Copyright (c) 2012 Red Hat, Inc
7  *
8  * This code is partly based on "USB HID support for Linux":
9  *
10  *  Copyright (c) 1999 Andreas Gal
11  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
12  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
13  *  Copyright (c) 2007-2008 Oliver Neukum
14  *  Copyright (c) 2006-2010 Jiri Kosina
15  *
16  * This file is subject to the terms and conditions of the GNU General Public
17  * License.  See the file COPYING in the main directory of this archive for
18  * more details.
19  */
20 
21 #include <linux/module.h>
22 #include <linux/i2c.h>
23 #include <linux/interrupt.h>
24 #include <linux/input.h>
25 #include <linux/irq.h>
26 #include <linux/delay.h>
27 #include <linux/slab.h>
28 #include <linux/pm.h>
29 #include <linux/pm_runtime.h>
30 #include <linux/device.h>
31 #include <linux/wait.h>
32 #include <linux/err.h>
33 #include <linux/string.h>
34 #include <linux/list.h>
35 #include <linux/jiffies.h>
36 #include <linux/kernel.h>
37 #include <linux/hid.h>
38 #include <linux/mutex.h>
39 #include <linux/acpi.h>
40 #include <linux/of.h>
41 #include <linux/regulator/consumer.h>
42 
43 #include <linux/platform_data/i2c-hid.h>
44 
45 #include "../hid-ids.h"
46 #include "i2c-hid.h"
47 
48 /* quirks to control the device */
49 #define I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV	BIT(0)
50 #define I2C_HID_QUIRK_NO_IRQ_AFTER_RESET	BIT(1)
51 #define I2C_HID_QUIRK_NO_RUNTIME_PM		BIT(2)
52 #define I2C_HID_QUIRK_DELAY_AFTER_SLEEP		BIT(3)
53 #define I2C_HID_QUIRK_BOGUS_IRQ			BIT(4)
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 	unsigned long		sleep_delay;
165 };
166 
167 static const struct i2c_hid_quirks {
168 	__u16 idVendor;
169 	__u16 idProduct;
170 	__u32 quirks;
171 } i2c_hid_quirks[] = {
172 	{ USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8752,
173 		I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
174 	{ USB_VENDOR_ID_WEIDA, USB_DEVICE_ID_WEIDA_8755,
175 		I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV },
176 	{ I2C_VENDOR_ID_HANTICK, I2C_PRODUCT_ID_HANTICK_5288,
177 		I2C_HID_QUIRK_NO_IRQ_AFTER_RESET |
178 		I2C_HID_QUIRK_NO_RUNTIME_PM },
179 	{ I2C_VENDOR_ID_RAYDIUM, I2C_PRODUCT_ID_RAYDIUM_4B33,
180 		I2C_HID_QUIRK_DELAY_AFTER_SLEEP },
181 	{ USB_VENDOR_ID_LG, I2C_DEVICE_ID_LG_8001,
182 		I2C_HID_QUIRK_NO_RUNTIME_PM },
183 	{ I2C_VENDOR_ID_GOODIX, I2C_DEVICE_ID_GOODIX_01F0,
184 		I2C_HID_QUIRK_NO_RUNTIME_PM },
185 	{ USB_VENDOR_ID_ELAN, HID_ANY_ID,
186 		 I2C_HID_QUIRK_BOGUS_IRQ },
187 	{ USB_VENDOR_ID_SYNAPTICS, I2C_DEVICE_ID_SYNAPTICS_7E7E,
188 		I2C_HID_QUIRK_NO_RUNTIME_PM },
189 	{ 0, 0 }
190 };
191 
192 /*
193  * i2c_hid_lookup_quirk: return any quirks associated with a I2C HID device
194  * @idVendor: the 16-bit vendor ID
195  * @idProduct: the 16-bit product ID
196  *
197  * Returns: a u32 quirks value.
198  */
199 static u32 i2c_hid_lookup_quirk(const u16 idVendor, const u16 idProduct)
200 {
201 	u32 quirks = 0;
202 	int n;
203 
204 	for (n = 0; i2c_hid_quirks[n].idVendor; n++)
205 		if (i2c_hid_quirks[n].idVendor == idVendor &&
206 		    (i2c_hid_quirks[n].idProduct == (__u16)HID_ANY_ID ||
207 		     i2c_hid_quirks[n].idProduct == idProduct))
208 			quirks = i2c_hid_quirks[n].quirks;
209 
210 	return quirks;
211 }
212 
213 static int __i2c_hid_command(struct i2c_client *client,
214 		const struct i2c_hid_cmd *command, u8 reportID,
215 		u8 reportType, u8 *args, int args_len,
216 		unsigned char *buf_recv, int data_len)
217 {
218 	struct i2c_hid *ihid = i2c_get_clientdata(client);
219 	union command *cmd = (union command *)ihid->cmdbuf;
220 	int ret;
221 	struct i2c_msg msg[2];
222 	int msg_num = 1;
223 
224 	int length = command->length;
225 	bool wait = command->wait;
226 	unsigned int registerIndex = command->registerIndex;
227 
228 	/* special case for hid_descr_cmd */
229 	if (command == &hid_descr_cmd) {
230 		cmd->c.reg = ihid->wHIDDescRegister;
231 	} else {
232 		cmd->data[0] = ihid->hdesc_buffer[registerIndex];
233 		cmd->data[1] = ihid->hdesc_buffer[registerIndex + 1];
234 	}
235 
236 	if (length > 2) {
237 		cmd->c.opcode = command->opcode;
238 		cmd->c.reportTypeID = reportID | reportType << 4;
239 	}
240 
241 	memcpy(cmd->data + length, args, args_len);
242 	length += args_len;
243 
244 	i2c_hid_dbg(ihid, "%s: cmd=%*ph\n", __func__, length, cmd->data);
245 
246 	msg[0].addr = client->addr;
247 	msg[0].flags = client->flags & I2C_M_TEN;
248 	msg[0].len = length;
249 	msg[0].buf = cmd->data;
250 	if (data_len > 0) {
251 		msg[1].addr = client->addr;
252 		msg[1].flags = client->flags & I2C_M_TEN;
253 		msg[1].flags |= I2C_M_RD;
254 		msg[1].len = data_len;
255 		msg[1].buf = buf_recv;
256 		msg_num = 2;
257 		set_bit(I2C_HID_READ_PENDING, &ihid->flags);
258 	}
259 
260 	if (wait)
261 		set_bit(I2C_HID_RESET_PENDING, &ihid->flags);
262 
263 	ret = i2c_transfer(client->adapter, msg, msg_num);
264 
265 	if (data_len > 0)
266 		clear_bit(I2C_HID_READ_PENDING, &ihid->flags);
267 
268 	if (ret != msg_num)
269 		return ret < 0 ? ret : -EIO;
270 
271 	ret = 0;
272 
273 	if (wait && (ihid->quirks & I2C_HID_QUIRK_NO_IRQ_AFTER_RESET)) {
274 		msleep(100);
275 	} else if (wait) {
276 		i2c_hid_dbg(ihid, "%s: waiting...\n", __func__);
277 		if (!wait_event_timeout(ihid->wait,
278 				!test_bit(I2C_HID_RESET_PENDING, &ihid->flags),
279 				msecs_to_jiffies(5000)))
280 			ret = -ENODATA;
281 		i2c_hid_dbg(ihid, "%s: finished.\n", __func__);
282 	}
283 
284 	return ret;
285 }
286 
287 static int i2c_hid_command(struct i2c_client *client,
288 		const struct i2c_hid_cmd *command,
289 		unsigned char *buf_recv, int data_len)
290 {
291 	return __i2c_hid_command(client, command, 0, 0, NULL, 0,
292 				buf_recv, data_len);
293 }
294 
295 static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
296 		u8 reportID, unsigned char *buf_recv, int data_len)
297 {
298 	struct i2c_hid *ihid = i2c_get_clientdata(client);
299 	u8 args[3];
300 	int ret;
301 	int args_len = 0;
302 	u16 readRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
303 
304 	i2c_hid_dbg(ihid, "%s\n", __func__);
305 
306 	if (reportID >= 0x0F) {
307 		args[args_len++] = reportID;
308 		reportID = 0x0F;
309 	}
310 
311 	args[args_len++] = readRegister & 0xFF;
312 	args[args_len++] = readRegister >> 8;
313 
314 	ret = __i2c_hid_command(client, &hid_get_report_cmd, reportID,
315 		reportType, args, args_len, buf_recv, data_len);
316 	if (ret) {
317 		dev_err(&client->dev,
318 			"failed to retrieve report from device.\n");
319 		return ret;
320 	}
321 
322 	return 0;
323 }
324 
325 /**
326  * i2c_hid_set_or_send_report: forward an incoming report to the device
327  * @client: the i2c_client of the device
328  * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
329  * @reportID: the report ID
330  * @buf: the actual data to transfer, without the report ID
331  * @len: size of buf
332  * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
333  */
334 static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
335 		u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
336 {
337 	struct i2c_hid *ihid = i2c_get_clientdata(client);
338 	u8 *args = ihid->argsbuf;
339 	const struct i2c_hid_cmd *hidcmd;
340 	int ret;
341 	u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
342 	u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
343 	u16 maxOutputLength = le16_to_cpu(ihid->hdesc.wMaxOutputLength);
344 	u16 size;
345 	int args_len;
346 	int index = 0;
347 
348 	i2c_hid_dbg(ihid, "%s\n", __func__);
349 
350 	if (data_len > ihid->bufsize)
351 		return -EINVAL;
352 
353 	size =		2			/* size */ +
354 			(reportID ? 1 : 0)	/* reportID */ +
355 			data_len		/* buf */;
356 	args_len =	(reportID >= 0x0F ? 1 : 0) /* optional third byte */ +
357 			2			/* dataRegister */ +
358 			size			/* args */;
359 
360 	if (!use_data && maxOutputLength == 0)
361 		return -ENOSYS;
362 
363 	if (reportID >= 0x0F) {
364 		args[index++] = reportID;
365 		reportID = 0x0F;
366 	}
367 
368 	/*
369 	 * use the data register for feature reports or if the device does not
370 	 * support the output register
371 	 */
372 	if (use_data) {
373 		args[index++] = dataRegister & 0xFF;
374 		args[index++] = dataRegister >> 8;
375 		hidcmd = &hid_set_report_cmd;
376 	} else {
377 		args[index++] = outputRegister & 0xFF;
378 		args[index++] = outputRegister >> 8;
379 		hidcmd = &hid_no_cmd;
380 	}
381 
382 	args[index++] = size & 0xFF;
383 	args[index++] = size >> 8;
384 
385 	if (reportID)
386 		args[index++] = reportID;
387 
388 	memcpy(&args[index], buf, data_len);
389 
390 	ret = __i2c_hid_command(client, hidcmd, reportID,
391 		reportType, args, args_len, NULL, 0);
392 	if (ret) {
393 		dev_err(&client->dev, "failed to set a report to device.\n");
394 		return ret;
395 	}
396 
397 	return data_len;
398 }
399 
400 static int i2c_hid_set_power(struct i2c_client *client, int power_state)
401 {
402 	struct i2c_hid *ihid = i2c_get_clientdata(client);
403 	int ret;
404 	unsigned long now, delay;
405 
406 	i2c_hid_dbg(ihid, "%s\n", __func__);
407 
408 	/*
409 	 * Some devices require to send a command to wakeup before power on.
410 	 * The call will get a return value (EREMOTEIO) but device will be
411 	 * triggered and activated. After that, it goes like a normal device.
412 	 */
413 	if (power_state == I2C_HID_PWR_ON &&
414 	    ihid->quirks & I2C_HID_QUIRK_SET_PWR_WAKEUP_DEV) {
415 		ret = i2c_hid_command(client, &hid_set_power_cmd, NULL, 0);
416 
417 		/* Device was already activated */
418 		if (!ret)
419 			goto set_pwr_exit;
420 	}
421 
422 	if (ihid->quirks & I2C_HID_QUIRK_DELAY_AFTER_SLEEP &&
423 	    power_state == I2C_HID_PWR_ON) {
424 		now = jiffies;
425 		if (time_after(ihid->sleep_delay, now)) {
426 			delay = jiffies_to_usecs(ihid->sleep_delay - now);
427 			usleep_range(delay, delay + 1);
428 		}
429 	}
430 
431 	ret = __i2c_hid_command(client, &hid_set_power_cmd, power_state,
432 		0, NULL, 0, NULL, 0);
433 
434 	if (ihid->quirks & I2C_HID_QUIRK_DELAY_AFTER_SLEEP &&
435 	    power_state == I2C_HID_PWR_SLEEP)
436 		ihid->sleep_delay = jiffies + msecs_to_jiffies(20);
437 
438 	if (ret)
439 		dev_err(&client->dev, "failed to change power setting.\n");
440 
441 set_pwr_exit:
442 	return ret;
443 }
444 
445 static int i2c_hid_hwreset(struct i2c_client *client)
446 {
447 	struct i2c_hid *ihid = i2c_get_clientdata(client);
448 	int ret;
449 
450 	i2c_hid_dbg(ihid, "%s\n", __func__);
451 
452 	/*
453 	 * This prevents sending feature reports while the device is
454 	 * being reset. Otherwise we may lose the reset complete
455 	 * interrupt.
456 	 */
457 	mutex_lock(&ihid->reset_lock);
458 
459 	ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
460 	if (ret)
461 		goto out_unlock;
462 
463 	/*
464 	 * The HID over I2C specification states that if a DEVICE needs time
465 	 * after the PWR_ON request, it should utilise CLOCK stretching.
466 	 * However, it has been observered that the Windows driver provides a
467 	 * 1ms sleep between the PWR_ON and RESET requests and that some devices
468 	 * rely on this.
469 	 */
470 	usleep_range(1000, 5000);
471 
472 	i2c_hid_dbg(ihid, "resetting...\n");
473 
474 	ret = i2c_hid_command(client, &hid_reset_cmd, NULL, 0);
475 	if (ret) {
476 		dev_err(&client->dev, "failed to reset device.\n");
477 		i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
478 	}
479 
480 out_unlock:
481 	mutex_unlock(&ihid->reset_lock);
482 	return ret;
483 }
484 
485 static void i2c_hid_get_input(struct i2c_hid *ihid)
486 {
487 	int ret;
488 	u32 ret_size;
489 	int size = le16_to_cpu(ihid->hdesc.wMaxInputLength);
490 
491 	if (size > ihid->bufsize)
492 		size = ihid->bufsize;
493 
494 	ret = i2c_master_recv(ihid->client, ihid->inbuf, size);
495 	if (ret != size) {
496 		if (ret < 0)
497 			return;
498 
499 		dev_err(&ihid->client->dev, "%s: got %d data instead of %d\n",
500 			__func__, ret, size);
501 		return;
502 	}
503 
504 	ret_size = ihid->inbuf[0] | ihid->inbuf[1] << 8;
505 
506 	if (!ret_size) {
507 		/* host or device initiated RESET completed */
508 		if (test_and_clear_bit(I2C_HID_RESET_PENDING, &ihid->flags))
509 			wake_up(&ihid->wait);
510 		return;
511 	}
512 
513 	if (ihid->quirks & I2C_HID_QUIRK_BOGUS_IRQ && ret_size == 0xffff) {
514 		dev_warn_once(&ihid->client->dev, "%s: IRQ triggered but "
515 			      "there's no data\n", __func__);
516 		return;
517 	}
518 
519 	if ((ret_size > size) || (ret_size < 2)) {
520 		dev_err(&ihid->client->dev, "%s: incomplete report (%d/%d)\n",
521 			__func__, size, ret_size);
522 		return;
523 	}
524 
525 	i2c_hid_dbg(ihid, "input: %*ph\n", ret_size, ihid->inbuf);
526 
527 	if (test_bit(I2C_HID_STARTED, &ihid->flags))
528 		hid_input_report(ihid->hid, HID_INPUT_REPORT, ihid->inbuf + 2,
529 				ret_size - 2, 1);
530 
531 	return;
532 }
533 
534 static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
535 {
536 	struct i2c_hid *ihid = dev_id;
537 
538 	if (test_bit(I2C_HID_READ_PENDING, &ihid->flags))
539 		return IRQ_HANDLED;
540 
541 	i2c_hid_get_input(ihid);
542 
543 	return IRQ_HANDLED;
544 }
545 
546 static int i2c_hid_get_report_length(struct hid_report *report)
547 {
548 	return ((report->size - 1) >> 3) + 1 +
549 		report->device->report_enum[report->type].numbered + 2;
550 }
551 
552 /*
553  * Traverse the supplied list of reports and find the longest
554  */
555 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
556 		unsigned int *max)
557 {
558 	struct hid_report *report;
559 	unsigned int size;
560 
561 	/* We should not rely on wMaxInputLength, as some devices may set it to
562 	 * a wrong length. */
563 	list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
564 		size = i2c_hid_get_report_length(report);
565 		if (*max < size)
566 			*max = size;
567 	}
568 }
569 
570 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
571 {
572 	kfree(ihid->inbuf);
573 	kfree(ihid->rawbuf);
574 	kfree(ihid->argsbuf);
575 	kfree(ihid->cmdbuf);
576 	ihid->inbuf = NULL;
577 	ihid->rawbuf = NULL;
578 	ihid->cmdbuf = NULL;
579 	ihid->argsbuf = NULL;
580 	ihid->bufsize = 0;
581 }
582 
583 static int i2c_hid_alloc_buffers(struct i2c_hid *ihid, size_t report_size)
584 {
585 	/* the worst case is computed from the set_report command with a
586 	 * reportID > 15 and the maximum report length */
587 	int args_len = sizeof(__u8) + /* ReportID */
588 		       sizeof(__u8) + /* optional ReportID byte */
589 		       sizeof(__u16) + /* data register */
590 		       sizeof(__u16) + /* size of the report */
591 		       report_size; /* report */
592 
593 	ihid->inbuf = kzalloc(report_size, GFP_KERNEL);
594 	ihid->rawbuf = kzalloc(report_size, GFP_KERNEL);
595 	ihid->argsbuf = kzalloc(args_len, GFP_KERNEL);
596 	ihid->cmdbuf = kzalloc(sizeof(union command) + args_len, GFP_KERNEL);
597 
598 	if (!ihid->inbuf || !ihid->rawbuf || !ihid->argsbuf || !ihid->cmdbuf) {
599 		i2c_hid_free_buffers(ihid);
600 		return -ENOMEM;
601 	}
602 
603 	ihid->bufsize = report_size;
604 
605 	return 0;
606 }
607 
608 static int i2c_hid_get_raw_report(struct hid_device *hid,
609 		unsigned char report_number, __u8 *buf, size_t count,
610 		unsigned char report_type)
611 {
612 	struct i2c_client *client = hid->driver_data;
613 	struct i2c_hid *ihid = i2c_get_clientdata(client);
614 	size_t ret_count, ask_count;
615 	int ret;
616 
617 	if (report_type == HID_OUTPUT_REPORT)
618 		return -EINVAL;
619 
620 	/* +2 bytes to include the size of the reply in the query buffer */
621 	ask_count = min(count + 2, (size_t)ihid->bufsize);
622 
623 	ret = i2c_hid_get_report(client,
624 			report_type == HID_FEATURE_REPORT ? 0x03 : 0x01,
625 			report_number, ihid->rawbuf, ask_count);
626 
627 	if (ret < 0)
628 		return ret;
629 
630 	ret_count = ihid->rawbuf[0] | (ihid->rawbuf[1] << 8);
631 
632 	if (ret_count <= 2)
633 		return 0;
634 
635 	ret_count = min(ret_count, ask_count);
636 
637 	/* The query buffer contains the size, dropping it in the reply */
638 	count = min(count, ret_count - 2);
639 	memcpy(buf, ihid->rawbuf + 2, count);
640 
641 	return count;
642 }
643 
644 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
645 		size_t count, unsigned char report_type, bool use_data)
646 {
647 	struct i2c_client *client = hid->driver_data;
648 	struct i2c_hid *ihid = i2c_get_clientdata(client);
649 	int report_id = buf[0];
650 	int ret;
651 
652 	if (report_type == HID_INPUT_REPORT)
653 		return -EINVAL;
654 
655 	mutex_lock(&ihid->reset_lock);
656 
657 	if (report_id) {
658 		buf++;
659 		count--;
660 	}
661 
662 	ret = i2c_hid_set_or_send_report(client,
663 				report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
664 				report_id, buf, count, use_data);
665 
666 	if (report_id && ret >= 0)
667 		ret++; /* add report_id to the number of transfered bytes */
668 
669 	mutex_unlock(&ihid->reset_lock);
670 
671 	return ret;
672 }
673 
674 static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
675 		size_t count)
676 {
677 	return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
678 			false);
679 }
680 
681 static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
682 			       __u8 *buf, size_t len, unsigned char rtype,
683 			       int reqtype)
684 {
685 	switch (reqtype) {
686 	case HID_REQ_GET_REPORT:
687 		return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
688 	case HID_REQ_SET_REPORT:
689 		if (buf[0] != reportnum)
690 			return -EINVAL;
691 		return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
692 	default:
693 		return -EIO;
694 	}
695 }
696 
697 static int i2c_hid_parse(struct hid_device *hid)
698 {
699 	struct i2c_client *client = hid->driver_data;
700 	struct i2c_hid *ihid = i2c_get_clientdata(client);
701 	struct i2c_hid_desc *hdesc = &ihid->hdesc;
702 	unsigned int rsize;
703 	char *rdesc;
704 	int ret;
705 	int tries = 3;
706 	char *use_override;
707 
708 	i2c_hid_dbg(ihid, "entering %s\n", __func__);
709 
710 	rsize = le16_to_cpu(hdesc->wReportDescLength);
711 	if (!rsize || rsize > HID_MAX_DESCRIPTOR_SIZE) {
712 		dbg_hid("weird size of report descriptor (%u)\n", rsize);
713 		return -EINVAL;
714 	}
715 
716 	do {
717 		ret = i2c_hid_hwreset(client);
718 		if (ret)
719 			msleep(1000);
720 	} while (tries-- > 0 && ret);
721 
722 	if (ret)
723 		return ret;
724 
725 	use_override = i2c_hid_get_dmi_hid_report_desc_override(client->name,
726 								&rsize);
727 
728 	if (use_override) {
729 		rdesc = use_override;
730 		i2c_hid_dbg(ihid, "Using a HID report descriptor override\n");
731 	} else {
732 		rdesc = kzalloc(rsize, GFP_KERNEL);
733 
734 		if (!rdesc) {
735 			dbg_hid("couldn't allocate rdesc memory\n");
736 			return -ENOMEM;
737 		}
738 
739 		i2c_hid_dbg(ihid, "asking HID report descriptor\n");
740 
741 		ret = i2c_hid_command(client, &hid_report_descr_cmd,
742 				      rdesc, rsize);
743 		if (ret) {
744 			hid_err(hid, "reading report descriptor failed\n");
745 			kfree(rdesc);
746 			return -EIO;
747 		}
748 	}
749 
750 	i2c_hid_dbg(ihid, "Report Descriptor: %*ph\n", rsize, rdesc);
751 
752 	ret = hid_parse_report(hid, rdesc, rsize);
753 	if (!use_override)
754 		kfree(rdesc);
755 
756 	if (ret) {
757 		dbg_hid("parsing report descriptor failed\n");
758 		return ret;
759 	}
760 
761 	return 0;
762 }
763 
764 static int i2c_hid_start(struct hid_device *hid)
765 {
766 	struct i2c_client *client = hid->driver_data;
767 	struct i2c_hid *ihid = i2c_get_clientdata(client);
768 	int ret;
769 	unsigned int bufsize = HID_MIN_BUFFER_SIZE;
770 
771 	i2c_hid_find_max_report(hid, HID_INPUT_REPORT, &bufsize);
772 	i2c_hid_find_max_report(hid, HID_OUTPUT_REPORT, &bufsize);
773 	i2c_hid_find_max_report(hid, HID_FEATURE_REPORT, &bufsize);
774 
775 	if (bufsize > ihid->bufsize) {
776 		disable_irq(client->irq);
777 		i2c_hid_free_buffers(ihid);
778 
779 		ret = i2c_hid_alloc_buffers(ihid, bufsize);
780 		enable_irq(client->irq);
781 
782 		if (ret)
783 			return ret;
784 	}
785 
786 	return 0;
787 }
788 
789 static void i2c_hid_stop(struct hid_device *hid)
790 {
791 	hid->claimed = 0;
792 }
793 
794 static int i2c_hid_open(struct hid_device *hid)
795 {
796 	struct i2c_client *client = hid->driver_data;
797 	struct i2c_hid *ihid = i2c_get_clientdata(client);
798 	int ret = 0;
799 
800 	ret = pm_runtime_get_sync(&client->dev);
801 	if (ret < 0)
802 		return ret;
803 
804 	set_bit(I2C_HID_STARTED, &ihid->flags);
805 	return 0;
806 }
807 
808 static void i2c_hid_close(struct hid_device *hid)
809 {
810 	struct i2c_client *client = hid->driver_data;
811 	struct i2c_hid *ihid = i2c_get_clientdata(client);
812 
813 	clear_bit(I2C_HID_STARTED, &ihid->flags);
814 
815 	/* Save some power */
816 	pm_runtime_put(&client->dev);
817 }
818 
819 static int i2c_hid_power(struct hid_device *hid, int lvl)
820 {
821 	struct i2c_client *client = hid->driver_data;
822 	struct i2c_hid *ihid = i2c_get_clientdata(client);
823 
824 	i2c_hid_dbg(ihid, "%s lvl:%d\n", __func__, lvl);
825 
826 	switch (lvl) {
827 	case PM_HINT_FULLON:
828 		pm_runtime_get_sync(&client->dev);
829 		break;
830 	case PM_HINT_NORMAL:
831 		pm_runtime_put(&client->dev);
832 		break;
833 	}
834 	return 0;
835 }
836 
837 struct hid_ll_driver i2c_hid_ll_driver = {
838 	.parse = i2c_hid_parse,
839 	.start = i2c_hid_start,
840 	.stop = i2c_hid_stop,
841 	.open = i2c_hid_open,
842 	.close = i2c_hid_close,
843 	.power = i2c_hid_power,
844 	.output_report = i2c_hid_output_report,
845 	.raw_request = i2c_hid_raw_request,
846 };
847 EXPORT_SYMBOL_GPL(i2c_hid_ll_driver);
848 
849 static int i2c_hid_init_irq(struct i2c_client *client)
850 {
851 	struct i2c_hid *ihid = i2c_get_clientdata(client);
852 	unsigned long irqflags = 0;
853 	int ret;
854 
855 	dev_dbg(&client->dev, "Requesting IRQ: %d\n", client->irq);
856 
857 	if (!irq_get_trigger_type(client->irq))
858 		irqflags = IRQF_TRIGGER_LOW;
859 
860 	ret = request_threaded_irq(client->irq, NULL, i2c_hid_irq,
861 				   irqflags | IRQF_ONESHOT, 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 
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 ret;
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 		ret = i2c_hid_command(client, &hid_descr_cmd,
889 				      ihid->hdesc_buffer,
890 				      sizeof(struct i2c_hid_desc));
891 		if (ret) {
892 			dev_err(&client->dev, "hid_descr_cmd failed\n");
893 			return -ENODEV;
894 		}
895 	}
896 
897 	/* Validate the length of HID descriptor, the 4 first bytes:
898 	 * bytes 0-1 -> length
899 	 * bytes 2-3 -> bcdVersion (has to be 1.00) */
900 	/* check bcdVersion == 1.0 */
901 	if (le16_to_cpu(hdesc->bcdVersion) != 0x0100) {
902 		dev_err(&client->dev,
903 			"unexpected HID descriptor bcdVersion (0x%04hx)\n",
904 			le16_to_cpu(hdesc->bcdVersion));
905 		return -ENODEV;
906 	}
907 
908 	/* Descriptor length should be 30 bytes as per the specification */
909 	dsize = le16_to_cpu(hdesc->wHIDDescLength);
910 	if (dsize != sizeof(struct i2c_hid_desc)) {
911 		dev_err(&client->dev, "weird size of HID descriptor (%u)\n",
912 			dsize);
913 		return -ENODEV;
914 	}
915 	i2c_hid_dbg(ihid, "HID Descriptor: %*ph\n", dsize, ihid->hdesc_buffer);
916 	return 0;
917 }
918 
919 #ifdef CONFIG_ACPI
920 static const struct acpi_device_id i2c_hid_acpi_blacklist[] = {
921 	/*
922 	 * The CHPN0001 ACPI device, which is used to describe the Chipone
923 	 * ICN8505 controller, has a _CID of PNP0C50 but is not HID compatible.
924 	 */
925 	{"CHPN0001", 0 },
926 	{ },
927 };
928 
929 static int i2c_hid_acpi_pdata(struct i2c_client *client,
930 		struct i2c_hid_platform_data *pdata)
931 {
932 	static guid_t i2c_hid_guid =
933 		GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
934 			  0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
935 	union acpi_object *obj;
936 	struct acpi_device *adev;
937 	acpi_handle handle;
938 
939 	handle = ACPI_HANDLE(&client->dev);
940 	if (!handle || acpi_bus_get_device(handle, &adev)) {
941 		dev_err(&client->dev, "Error could not get ACPI device\n");
942 		return -ENODEV;
943 	}
944 
945 	if (acpi_match_device_ids(adev, i2c_hid_acpi_blacklist) == 0)
946 		return -ENODEV;
947 
948 	obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL,
949 				      ACPI_TYPE_INTEGER);
950 	if (!obj) {
951 		dev_err(&client->dev, "Error _DSM call to get HID descriptor address failed\n");
952 		return -ENODEV;
953 	}
954 
955 	pdata->hid_descriptor_address = obj->integer.value;
956 	ACPI_FREE(obj);
957 
958 	return 0;
959 }
960 
961 static void i2c_hid_acpi_fix_up_power(struct device *dev)
962 {
963 	struct acpi_device *adev;
964 
965 	adev = ACPI_COMPANION(dev);
966 	if (adev)
967 		acpi_device_fix_up_power(adev);
968 }
969 
970 static const struct acpi_device_id i2c_hid_acpi_match[] = {
971 	{"ACPI0C50", 0 },
972 	{"PNP0C50", 0 },
973 	{ },
974 };
975 MODULE_DEVICE_TABLE(acpi, i2c_hid_acpi_match);
976 #else
977 static inline int i2c_hid_acpi_pdata(struct i2c_client *client,
978 		struct i2c_hid_platform_data *pdata)
979 {
980 	return -ENODEV;
981 }
982 
983 static inline void i2c_hid_acpi_fix_up_power(struct device *dev) {}
984 #endif
985 
986 #ifdef CONFIG_OF
987 static int i2c_hid_of_probe(struct i2c_client *client,
988 		struct i2c_hid_platform_data *pdata)
989 {
990 	struct device *dev = &client->dev;
991 	u32 val;
992 	int ret;
993 
994 	ret = of_property_read_u32(dev->of_node, "hid-descr-addr", &val);
995 	if (ret) {
996 		dev_err(&client->dev, "HID register address not provided\n");
997 		return -ENODEV;
998 	}
999 	if (val >> 16) {
1000 		dev_err(&client->dev, "Bad HID register address: 0x%08x\n",
1001 			val);
1002 		return -EINVAL;
1003 	}
1004 	pdata->hid_descriptor_address = val;
1005 
1006 	return 0;
1007 }
1008 
1009 static const struct of_device_id i2c_hid_of_match[] = {
1010 	{ .compatible = "hid-over-i2c" },
1011 	{},
1012 };
1013 MODULE_DEVICE_TABLE(of, i2c_hid_of_match);
1014 #else
1015 static inline int i2c_hid_of_probe(struct i2c_client *client,
1016 		struct i2c_hid_platform_data *pdata)
1017 {
1018 	return -ENODEV;
1019 }
1020 #endif
1021 
1022 static void i2c_hid_fwnode_probe(struct i2c_client *client,
1023 				 struct i2c_hid_platform_data *pdata)
1024 {
1025 	u32 val;
1026 
1027 	if (!device_property_read_u32(&client->dev, "post-power-on-delay-ms",
1028 				      &val))
1029 		pdata->post_power_delay_ms = val;
1030 }
1031 
1032 static int i2c_hid_probe(struct i2c_client *client,
1033 			 const struct i2c_device_id *dev_id)
1034 {
1035 	int ret;
1036 	struct i2c_hid *ihid;
1037 	struct hid_device *hid;
1038 	__u16 hidRegister;
1039 	struct i2c_hid_platform_data *platform_data = client->dev.platform_data;
1040 
1041 	dbg_hid("HID probe called for i2c 0x%02x\n", client->addr);
1042 
1043 	if (!client->irq) {
1044 		dev_err(&client->dev,
1045 			"HID over i2c has not been provided an Int IRQ\n");
1046 		return -EINVAL;
1047 	}
1048 
1049 	if (client->irq < 0) {
1050 		if (client->irq != -EPROBE_DEFER)
1051 			dev_err(&client->dev,
1052 				"HID over i2c doesn't have a valid IRQ\n");
1053 		return client->irq;
1054 	}
1055 
1056 	ihid = devm_kzalloc(&client->dev, sizeof(*ihid), GFP_KERNEL);
1057 	if (!ihid)
1058 		return -ENOMEM;
1059 
1060 	if (client->dev.of_node) {
1061 		ret = i2c_hid_of_probe(client, &ihid->pdata);
1062 		if (ret)
1063 			return ret;
1064 	} else if (!platform_data) {
1065 		ret = i2c_hid_acpi_pdata(client, &ihid->pdata);
1066 		if (ret)
1067 			return ret;
1068 	} else {
1069 		ihid->pdata = *platform_data;
1070 	}
1071 
1072 	/* Parse platform agnostic common properties from ACPI / device tree */
1073 	i2c_hid_fwnode_probe(client, &ihid->pdata);
1074 
1075 	ihid->pdata.supplies[0].supply = "vdd";
1076 	ihid->pdata.supplies[1].supply = "vddl";
1077 
1078 	ret = devm_regulator_bulk_get(&client->dev,
1079 				      ARRAY_SIZE(ihid->pdata.supplies),
1080 				      ihid->pdata.supplies);
1081 	if (ret)
1082 		return ret;
1083 
1084 	ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1085 				    ihid->pdata.supplies);
1086 	if (ret < 0)
1087 		return ret;
1088 
1089 	if (ihid->pdata.post_power_delay_ms)
1090 		msleep(ihid->pdata.post_power_delay_ms);
1091 
1092 	i2c_set_clientdata(client, ihid);
1093 
1094 	ihid->client = client;
1095 
1096 	hidRegister = ihid->pdata.hid_descriptor_address;
1097 	ihid->wHIDDescRegister = cpu_to_le16(hidRegister);
1098 
1099 	init_waitqueue_head(&ihid->wait);
1100 	mutex_init(&ihid->reset_lock);
1101 
1102 	/* we need to allocate the command buffer without knowing the maximum
1103 	 * size of the reports. Let's use HID_MIN_BUFFER_SIZE, then we do the
1104 	 * real computation later. */
1105 	ret = i2c_hid_alloc_buffers(ihid, HID_MIN_BUFFER_SIZE);
1106 	if (ret < 0)
1107 		goto err_regulator;
1108 
1109 	i2c_hid_acpi_fix_up_power(&client->dev);
1110 
1111 	pm_runtime_get_noresume(&client->dev);
1112 	pm_runtime_set_active(&client->dev);
1113 	pm_runtime_enable(&client->dev);
1114 	device_enable_async_suspend(&client->dev);
1115 
1116 	/* Make sure there is something at this address */
1117 	ret = i2c_smbus_read_byte(client);
1118 	if (ret < 0) {
1119 		dev_dbg(&client->dev, "nothing at this address: %d\n", ret);
1120 		ret = -ENXIO;
1121 		goto err_pm;
1122 	}
1123 
1124 	ret = i2c_hid_fetch_hid_descriptor(ihid);
1125 	if (ret < 0)
1126 		goto err_pm;
1127 
1128 	ret = i2c_hid_init_irq(client);
1129 	if (ret < 0)
1130 		goto err_pm;
1131 
1132 	hid = hid_allocate_device();
1133 	if (IS_ERR(hid)) {
1134 		ret = PTR_ERR(hid);
1135 		goto err_irq;
1136 	}
1137 
1138 	ihid->hid = hid;
1139 
1140 	hid->driver_data = client;
1141 	hid->ll_driver = &i2c_hid_ll_driver;
1142 	hid->dev.parent = &client->dev;
1143 	hid->bus = BUS_I2C;
1144 	hid->version = le16_to_cpu(ihid->hdesc.bcdVersion);
1145 	hid->vendor = le16_to_cpu(ihid->hdesc.wVendorID);
1146 	hid->product = le16_to_cpu(ihid->hdesc.wProductID);
1147 
1148 	snprintf(hid->name, sizeof(hid->name), "%s %04hX:%04hX",
1149 		 client->name, hid->vendor, hid->product);
1150 	strlcpy(hid->phys, dev_name(&client->dev), sizeof(hid->phys));
1151 
1152 	ihid->quirks = i2c_hid_lookup_quirk(hid->vendor, hid->product);
1153 
1154 	ret = hid_add_device(hid);
1155 	if (ret) {
1156 		if (ret != -ENODEV)
1157 			hid_err(client, "can't add hid device: %d\n", ret);
1158 		goto err_mem_free;
1159 	}
1160 
1161 	if (!(ihid->quirks & I2C_HID_QUIRK_NO_RUNTIME_PM))
1162 		pm_runtime_put(&client->dev);
1163 
1164 	return 0;
1165 
1166 err_mem_free:
1167 	hid_destroy_device(hid);
1168 
1169 err_irq:
1170 	free_irq(client->irq, ihid);
1171 
1172 err_pm:
1173 	pm_runtime_put_noidle(&client->dev);
1174 	pm_runtime_disable(&client->dev);
1175 
1176 err_regulator:
1177 	regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1178 			       ihid->pdata.supplies);
1179 	i2c_hid_free_buffers(ihid);
1180 	return ret;
1181 }
1182 
1183 static int i2c_hid_remove(struct i2c_client *client)
1184 {
1185 	struct i2c_hid *ihid = i2c_get_clientdata(client);
1186 	struct hid_device *hid;
1187 
1188 	if (!(ihid->quirks & I2C_HID_QUIRK_NO_RUNTIME_PM))
1189 		pm_runtime_get_sync(&client->dev);
1190 	pm_runtime_disable(&client->dev);
1191 	pm_runtime_set_suspended(&client->dev);
1192 	pm_runtime_put_noidle(&client->dev);
1193 
1194 	hid = ihid->hid;
1195 	hid_destroy_device(hid);
1196 
1197 	free_irq(client->irq, ihid);
1198 
1199 	if (ihid->bufsize)
1200 		i2c_hid_free_buffers(ihid);
1201 
1202 	regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1203 			       ihid->pdata.supplies);
1204 
1205 	return 0;
1206 }
1207 
1208 static void i2c_hid_shutdown(struct i2c_client *client)
1209 {
1210 	struct i2c_hid *ihid = i2c_get_clientdata(client);
1211 
1212 	i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1213 	free_irq(client->irq, ihid);
1214 }
1215 
1216 #ifdef CONFIG_PM_SLEEP
1217 static int i2c_hid_suspend(struct device *dev)
1218 {
1219 	struct i2c_client *client = to_i2c_client(dev);
1220 	struct i2c_hid *ihid = i2c_get_clientdata(client);
1221 	struct hid_device *hid = ihid->hid;
1222 	int ret;
1223 	int wake_status;
1224 
1225 	if (hid->driver && hid->driver->suspend) {
1226 		/*
1227 		 * Wake up the device so that IO issues in
1228 		 * HID driver's suspend code can succeed.
1229 		 */
1230 		ret = pm_runtime_resume(dev);
1231 		if (ret < 0)
1232 			return ret;
1233 
1234 		ret = hid->driver->suspend(hid, PMSG_SUSPEND);
1235 		if (ret < 0)
1236 			return ret;
1237 	}
1238 
1239 	if (!pm_runtime_suspended(dev)) {
1240 		/* Save some power */
1241 		i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1242 
1243 		disable_irq(client->irq);
1244 	}
1245 
1246 	if (device_may_wakeup(&client->dev)) {
1247 		wake_status = enable_irq_wake(client->irq);
1248 		if (!wake_status)
1249 			ihid->irq_wake_enabled = true;
1250 		else
1251 			hid_warn(hid, "Failed to enable irq wake: %d\n",
1252 				wake_status);
1253 	} else {
1254 		regulator_bulk_disable(ARRAY_SIZE(ihid->pdata.supplies),
1255 				       ihid->pdata.supplies);
1256 	}
1257 
1258 	return 0;
1259 }
1260 
1261 static int i2c_hid_resume(struct device *dev)
1262 {
1263 	int ret;
1264 	struct i2c_client *client = to_i2c_client(dev);
1265 	struct i2c_hid *ihid = i2c_get_clientdata(client);
1266 	struct hid_device *hid = ihid->hid;
1267 	int wake_status;
1268 
1269 	if (!device_may_wakeup(&client->dev)) {
1270 		ret = regulator_bulk_enable(ARRAY_SIZE(ihid->pdata.supplies),
1271 					    ihid->pdata.supplies);
1272 		if (ret)
1273 			hid_warn(hid, "Failed to enable supplies: %d\n", ret);
1274 
1275 		if (ihid->pdata.post_power_delay_ms)
1276 			msleep(ihid->pdata.post_power_delay_ms);
1277 	} else if (ihid->irq_wake_enabled) {
1278 		wake_status = disable_irq_wake(client->irq);
1279 		if (!wake_status)
1280 			ihid->irq_wake_enabled = false;
1281 		else
1282 			hid_warn(hid, "Failed to disable irq wake: %d\n",
1283 				wake_status);
1284 	}
1285 
1286 	/* We'll resume to full power */
1287 	pm_runtime_disable(dev);
1288 	pm_runtime_set_active(dev);
1289 	pm_runtime_enable(dev);
1290 
1291 	enable_irq(client->irq);
1292 
1293 	/* Instead of resetting device, simply powers the device on. This
1294 	 * solves "incomplete reports" on Raydium devices 2386:3118 and
1295 	 * 2386:4B33 and fixes various SIS touchscreens no longer sending
1296 	 * data after a suspend/resume.
1297 	 */
1298 	ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
1299 	if (ret)
1300 		return ret;
1301 
1302 	if (hid->driver && hid->driver->reset_resume) {
1303 		ret = hid->driver->reset_resume(hid);
1304 		return ret;
1305 	}
1306 
1307 	return 0;
1308 }
1309 #endif
1310 
1311 #ifdef CONFIG_PM
1312 static int i2c_hid_runtime_suspend(struct device *dev)
1313 {
1314 	struct i2c_client *client = to_i2c_client(dev);
1315 
1316 	i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
1317 	disable_irq(client->irq);
1318 	return 0;
1319 }
1320 
1321 static int i2c_hid_runtime_resume(struct device *dev)
1322 {
1323 	struct i2c_client *client = to_i2c_client(dev);
1324 
1325 	enable_irq(client->irq);
1326 	i2c_hid_set_power(client, I2C_HID_PWR_ON);
1327 	return 0;
1328 }
1329 #endif
1330 
1331 static const struct dev_pm_ops i2c_hid_pm = {
1332 	SET_SYSTEM_SLEEP_PM_OPS(i2c_hid_suspend, i2c_hid_resume)
1333 	SET_RUNTIME_PM_OPS(i2c_hid_runtime_suspend, i2c_hid_runtime_resume,
1334 			   NULL)
1335 };
1336 
1337 static const struct i2c_device_id i2c_hid_id_table[] = {
1338 	{ "hid", 0 },
1339 	{ "hid-over-i2c", 0 },
1340 	{ },
1341 };
1342 MODULE_DEVICE_TABLE(i2c, i2c_hid_id_table);
1343 
1344 
1345 static struct i2c_driver i2c_hid_driver = {
1346 	.driver = {
1347 		.name	= "i2c_hid",
1348 		.pm	= &i2c_hid_pm,
1349 		.acpi_match_table = ACPI_PTR(i2c_hid_acpi_match),
1350 		.of_match_table = of_match_ptr(i2c_hid_of_match),
1351 	},
1352 
1353 	.probe		= i2c_hid_probe,
1354 	.remove		= i2c_hid_remove,
1355 	.shutdown	= i2c_hid_shutdown,
1356 	.id_table	= i2c_hid_id_table,
1357 };
1358 
1359 module_i2c_driver(i2c_hid_driver);
1360 
1361 MODULE_DESCRIPTION("HID over I2C core driver");
1362 MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
1363 MODULE_LICENSE("GPL");
1364