xref: /linux/drivers/input/mouse/synaptics_i2c.c (revision 58f6259b7a08f8d47d4629609703d358b042f0fd)
1 /*
2  * Synaptics touchpad with I2C interface
3  *
4  * Copyright (C) 2009 Compulab, Ltd.
5  * Mike Rapoport <mike@compulab.co.il>
6  * Igor Grinberg <grinberg@compulab.co.il>
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file COPYING in the main directory of this archive for
10  * more details.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/i2c.h>
15 #include <linux/irq.h>
16 #include <linux/interrupt.h>
17 #include <linux/input.h>
18 #include <linux/delay.h>
19 #include <linux/workqueue.h>
20 #include <linux/slab.h>
21 #include <linux/pm.h>
22 
23 #define DRIVER_NAME		"synaptics_i2c"
24 /* maximum product id is 15 characters */
25 #define PRODUCT_ID_LENGTH	15
26 #define REGISTER_LENGTH		8
27 
28 /*
29  * after soft reset, we should wait for 1 ms
30  * before the device becomes operational
31  */
32 #define SOFT_RESET_DELAY_US	3000
33 /* and after hard reset, we should wait for max 500ms */
34 #define HARD_RESET_DELAY_MS	500
35 
36 /* Registers by SMBus address */
37 #define PAGE_SEL_REG		0xff
38 #define DEVICE_STATUS_REG	0x09
39 
40 /* Registers by RMI address */
41 #define DEV_CONTROL_REG		0x0000
42 #define INTERRUPT_EN_REG	0x0001
43 #define ERR_STAT_REG		0x0002
44 #define INT_REQ_STAT_REG	0x0003
45 #define DEV_COMMAND_REG		0x0004
46 
47 #define RMI_PROT_VER_REG	0x0200
48 #define MANUFACT_ID_REG		0x0201
49 #define PHYS_INT_VER_REG	0x0202
50 #define PROD_PROPERTY_REG	0x0203
51 #define INFO_QUERY_REG0		0x0204
52 #define INFO_QUERY_REG1		(INFO_QUERY_REG0 + 1)
53 #define INFO_QUERY_REG2		(INFO_QUERY_REG0 + 2)
54 #define INFO_QUERY_REG3		(INFO_QUERY_REG0 + 3)
55 
56 #define PRODUCT_ID_REG0		0x0210
57 #define PRODUCT_ID_REG1		(PRODUCT_ID_REG0 + 1)
58 #define PRODUCT_ID_REG2		(PRODUCT_ID_REG0 + 2)
59 #define PRODUCT_ID_REG3		(PRODUCT_ID_REG0 + 3)
60 #define PRODUCT_ID_REG4		(PRODUCT_ID_REG0 + 4)
61 #define PRODUCT_ID_REG5		(PRODUCT_ID_REG0 + 5)
62 #define PRODUCT_ID_REG6		(PRODUCT_ID_REG0 + 6)
63 #define PRODUCT_ID_REG7		(PRODUCT_ID_REG0 + 7)
64 #define PRODUCT_ID_REG8		(PRODUCT_ID_REG0 + 8)
65 #define PRODUCT_ID_REG9		(PRODUCT_ID_REG0 + 9)
66 #define PRODUCT_ID_REG10	(PRODUCT_ID_REG0 + 10)
67 #define PRODUCT_ID_REG11	(PRODUCT_ID_REG0 + 11)
68 #define PRODUCT_ID_REG12	(PRODUCT_ID_REG0 + 12)
69 #define PRODUCT_ID_REG13	(PRODUCT_ID_REG0 + 13)
70 #define PRODUCT_ID_REG14	(PRODUCT_ID_REG0 + 14)
71 #define PRODUCT_ID_REG15	(PRODUCT_ID_REG0 + 15)
72 
73 #define DATA_REG0		0x0400
74 #define ABS_PRESSURE_REG	0x0401
75 #define ABS_MSB_X_REG		0x0402
76 #define ABS_LSB_X_REG		(ABS_MSB_X_REG + 1)
77 #define ABS_MSB_Y_REG		0x0404
78 #define ABS_LSB_Y_REG		(ABS_MSB_Y_REG + 1)
79 #define REL_X_REG		0x0406
80 #define REL_Y_REG		0x0407
81 
82 #define DEV_QUERY_REG0		0x1000
83 #define DEV_QUERY_REG1		(DEV_QUERY_REG0 + 1)
84 #define DEV_QUERY_REG2		(DEV_QUERY_REG0 + 2)
85 #define DEV_QUERY_REG3		(DEV_QUERY_REG0 + 3)
86 #define DEV_QUERY_REG4		(DEV_QUERY_REG0 + 4)
87 #define DEV_QUERY_REG5		(DEV_QUERY_REG0 + 5)
88 #define DEV_QUERY_REG6		(DEV_QUERY_REG0 + 6)
89 #define DEV_QUERY_REG7		(DEV_QUERY_REG0 + 7)
90 #define DEV_QUERY_REG8		(DEV_QUERY_REG0 + 8)
91 
92 #define GENERAL_2D_CONTROL_REG	0x1041
93 #define SENSOR_SENSITIVITY_REG	0x1044
94 #define SENS_MAX_POS_MSB_REG	0x1046
95 #define SENS_MAX_POS_LSB_REG	(SENS_MAX_POS_UPPER_REG + 1)
96 
97 /* Register bits */
98 /* Device Control Register Bits */
99 #define REPORT_RATE_1ST_BIT	6
100 
101 /* Interrupt Enable Register Bits (INTERRUPT_EN_REG) */
102 #define F10_ABS_INT_ENA		0
103 #define F10_REL_INT_ENA		1
104 #define F20_INT_ENA		2
105 
106 /* Interrupt Request Register Bits (INT_REQ_STAT_REG | DEVICE_STATUS_REG) */
107 #define F10_ABS_INT_REQ		0
108 #define F10_REL_INT_REQ		1
109 #define F20_INT_REQ		2
110 /* Device Status Register Bits (DEVICE_STATUS_REG) */
111 #define STAT_CONFIGURED		6
112 #define STAT_ERROR		7
113 
114 /* Device Command Register Bits (DEV_COMMAND_REG) */
115 #define RESET_COMMAND		0x01
116 #define REZERO_COMMAND		0x02
117 
118 /* Data Register 0 Bits (DATA_REG0) */
119 #define GESTURE			3
120 
121 /* Device Query Registers Bits */
122 /* DEV_QUERY_REG3 */
123 #define HAS_PALM_DETECT		1
124 #define HAS_MULTI_FING		2
125 #define HAS_SCROLLER		4
126 #define HAS_2D_SCROLL		5
127 
128 /* General 2D Control Register Bits (GENERAL_2D_CONTROL_REG) */
129 #define NO_DECELERATION		1
130 #define REDUCE_REPORTING	3
131 #define NO_FILTER		5
132 
133 /* Function Masks */
134 /* Device Control Register Masks (DEV_CONTROL_REG) */
135 #define REPORT_RATE_MSK		0xc0
136 #define SLEEP_MODE_MSK		0x07
137 
138 /* Device Sleep Modes */
139 #define FULL_AWAKE		0x0
140 #define NORMAL_OP		0x1
141 #define LOW_PWR_OP		0x2
142 #define VERY_LOW_PWR_OP		0x3
143 #define SENS_SLEEP		0x4
144 #define SLEEP_MOD		0x5
145 #define DEEP_SLEEP		0x6
146 #define HIBERNATE		0x7
147 
148 /* Interrupt Register Mask */
149 /* (INT_REQ_STAT_REG | DEVICE_STATUS_REG | INTERRUPT_EN_REG) */
150 #define INT_ENA_REQ_MSK		0x07
151 #define INT_ENA_ABS_MSK		0x01
152 #define INT_ENA_REL_MSK		0x02
153 #define INT_ENA_F20_MSK		0x04
154 
155 /* Device Status Register Masks (DEVICE_STATUS_REG) */
156 #define CONFIGURED_MSK		0x40
157 #define ERROR_MSK		0x80
158 
159 /* Data Register 0 Masks */
160 #define FINGER_WIDTH_MSK	0xf0
161 #define GESTURE_MSK		0x08
162 #define SENSOR_STATUS_MSK	0x07
163 
164 /*
165  * MSB Position Register Masks
166  * ABS_MSB_X_REG | ABS_MSB_Y_REG | SENS_MAX_POS_MSB_REG |
167  * DEV_QUERY_REG3 | DEV_QUERY_REG5
168  */
169 #define MSB_POSITION_MSK	0x1f
170 
171 /* Device Query Registers Masks */
172 
173 /* DEV_QUERY_REG2 */
174 #define NUM_EXTRA_POS_MSK	0x07
175 
176 /* When in IRQ mode read the device every THREAD_IRQ_SLEEP_SECS */
177 #define THREAD_IRQ_SLEEP_SECS	2
178 #define THREAD_IRQ_SLEEP_MSECS	(THREAD_IRQ_SLEEP_SECS * MSEC_PER_SEC)
179 
180 /*
181  * When in Polling mode and no data received for NO_DATA_THRES msecs
182  * reduce the polling rate to NO_DATA_SLEEP_MSECS
183  */
184 #define NO_DATA_THRES		(MSEC_PER_SEC)
185 #define NO_DATA_SLEEP_MSECS	(MSEC_PER_SEC / 4)
186 
187 /* Control touchpad's No Deceleration option */
188 static bool no_decel = true;
189 module_param(no_decel, bool, 0644);
190 MODULE_PARM_DESC(no_decel, "No Deceleration. Default = 1 (on)");
191 
192 /* Control touchpad's Reduced Reporting option */
193 static bool reduce_report;
194 module_param(reduce_report, bool, 0644);
195 MODULE_PARM_DESC(reduce_report, "Reduced Reporting. Default = 0 (off)");
196 
197 /* Control touchpad's No Filter option */
198 static bool no_filter;
199 module_param(no_filter, bool, 0644);
200 MODULE_PARM_DESC(no_filter, "No Filter. Default = 0 (off)");
201 
202 /*
203  * touchpad Attention line is Active Low and Open Drain,
204  * therefore should be connected to pulled up line
205  * and the irq configuration should be set to Falling Edge Trigger
206  */
207 /* Control IRQ / Polling option */
208 static bool polling_req;
209 module_param(polling_req, bool, 0444);
210 MODULE_PARM_DESC(polling_req, "Request Polling. Default = 0 (use irq)");
211 
212 /* Control Polling Rate */
213 static int scan_rate = 80;
214 module_param(scan_rate, int, 0644);
215 MODULE_PARM_DESC(scan_rate, "Polling rate in times/sec. Default = 80");
216 
217 /* The main device structure */
218 struct synaptics_i2c {
219 	struct i2c_client	*client;
220 	struct input_dev	*input;
221 	struct delayed_work	dwork;
222 	int			no_data_count;
223 	int			no_decel_param;
224 	int			reduce_report_param;
225 	int			no_filter_param;
226 	int			scan_rate_param;
227 	int			scan_ms;
228 };
229 
230 static inline void set_scan_rate(struct synaptics_i2c *touch, int scan_rate)
231 {
232 	touch->scan_ms = MSEC_PER_SEC / scan_rate;
233 	touch->scan_rate_param = scan_rate;
234 }
235 
236 /*
237  * Driver's initial design makes no race condition possible on i2c bus,
238  * so there is no need in any locking.
239  * Keep it in mind, while playing with the code.
240  */
241 static s32 synaptics_i2c_reg_get(struct i2c_client *client, u16 reg)
242 {
243 	int ret;
244 
245 	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
246 	if (ret == 0)
247 		ret = i2c_smbus_read_byte_data(client, reg & 0xff);
248 
249 	return ret;
250 }
251 
252 static s32 synaptics_i2c_reg_set(struct i2c_client *client, u16 reg, u8 val)
253 {
254 	int ret;
255 
256 	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
257 	if (ret == 0)
258 		ret = i2c_smbus_write_byte_data(client, reg & 0xff, val);
259 
260 	return ret;
261 }
262 
263 static s32 synaptics_i2c_word_get(struct i2c_client *client, u16 reg)
264 {
265 	int ret;
266 
267 	ret = i2c_smbus_write_byte_data(client, PAGE_SEL_REG, reg >> 8);
268 	if (ret == 0)
269 		ret = i2c_smbus_read_word_data(client, reg & 0xff);
270 
271 	return ret;
272 }
273 
274 static int synaptics_i2c_config(struct i2c_client *client)
275 {
276 	int ret, control;
277 	u8 int_en;
278 
279 	/* set Report Rate to Device Highest (>=80) and Sleep to normal */
280 	ret = synaptics_i2c_reg_set(client, DEV_CONTROL_REG, 0xc1);
281 	if (ret)
282 		return ret;
283 
284 	/* set Interrupt Disable to Func20 / Enable to Func10) */
285 	int_en = (polling_req) ? 0 : INT_ENA_ABS_MSK | INT_ENA_REL_MSK;
286 	ret = synaptics_i2c_reg_set(client, INTERRUPT_EN_REG, int_en);
287 	if (ret)
288 		return ret;
289 
290 	control = synaptics_i2c_reg_get(client, GENERAL_2D_CONTROL_REG);
291 	/* No Deceleration */
292 	control |= no_decel ? 1 << NO_DECELERATION : 0;
293 	/* Reduced Reporting */
294 	control |= reduce_report ? 1 << REDUCE_REPORTING : 0;
295 	/* No Filter */
296 	control |= no_filter ? 1 << NO_FILTER : 0;
297 	ret = synaptics_i2c_reg_set(client, GENERAL_2D_CONTROL_REG, control);
298 	if (ret)
299 		return ret;
300 
301 	return 0;
302 }
303 
304 static int synaptics_i2c_reset_config(struct i2c_client *client)
305 {
306 	int ret;
307 
308 	/* Reset the Touchpad */
309 	ret = synaptics_i2c_reg_set(client, DEV_COMMAND_REG, RESET_COMMAND);
310 	if (ret) {
311 		dev_err(&client->dev, "Unable to reset device\n");
312 	} else {
313 		usleep_range(SOFT_RESET_DELAY_US, SOFT_RESET_DELAY_US + 100);
314 		ret = synaptics_i2c_config(client);
315 		if (ret)
316 			dev_err(&client->dev, "Unable to config device\n");
317 	}
318 
319 	return ret;
320 }
321 
322 static int synaptics_i2c_check_error(struct i2c_client *client)
323 {
324 	int status, ret = 0;
325 
326 	status = i2c_smbus_read_byte_data(client, DEVICE_STATUS_REG) &
327 		(CONFIGURED_MSK | ERROR_MSK);
328 
329 	if (status != CONFIGURED_MSK)
330 		ret = synaptics_i2c_reset_config(client);
331 
332 	return ret;
333 }
334 
335 static bool synaptics_i2c_get_input(struct synaptics_i2c *touch)
336 {
337 	struct input_dev *input = touch->input;
338 	int xy_delta, gesture;
339 	s32 data;
340 	s8 x_delta, y_delta;
341 
342 	/* Deal with spontaneous resets and errors */
343 	if (synaptics_i2c_check_error(touch->client))
344 		return false;
345 
346 	/* Get Gesture Bit */
347 	data = synaptics_i2c_reg_get(touch->client, DATA_REG0);
348 	gesture = (data >> GESTURE) & 0x1;
349 
350 	/*
351 	 * Get Relative axes. we have to get them in one shot,
352 	 * so we get 2 bytes starting from REL_X_REG.
353 	 */
354 	xy_delta = synaptics_i2c_word_get(touch->client, REL_X_REG) & 0xffff;
355 
356 	/* Separate X from Y */
357 	x_delta = xy_delta & 0xff;
358 	y_delta = (xy_delta >> REGISTER_LENGTH) & 0xff;
359 
360 	/* Report the button event */
361 	input_report_key(input, BTN_LEFT, gesture);
362 
363 	/* Report the deltas */
364 	input_report_rel(input, REL_X, x_delta);
365 	input_report_rel(input, REL_Y, -y_delta);
366 	input_sync(input);
367 
368 	return xy_delta || gesture;
369 }
370 
371 static irqreturn_t synaptics_i2c_irq(int irq, void *dev_id)
372 {
373 	struct synaptics_i2c *touch = dev_id;
374 
375 	mod_delayed_work(system_wq, &touch->dwork, 0);
376 
377 	return IRQ_HANDLED;
378 }
379 
380 static void synaptics_i2c_check_params(struct synaptics_i2c *touch)
381 {
382 	bool reset = false;
383 
384 	if (scan_rate != touch->scan_rate_param)
385 		set_scan_rate(touch, scan_rate);
386 
387 	if (no_decel != touch->no_decel_param) {
388 		touch->no_decel_param = no_decel;
389 		reset = true;
390 	}
391 
392 	if (no_filter != touch->no_filter_param) {
393 		touch->no_filter_param = no_filter;
394 		reset = true;
395 	}
396 
397 	if (reduce_report != touch->reduce_report_param) {
398 		touch->reduce_report_param = reduce_report;
399 		reset = true;
400 	}
401 
402 	if (reset)
403 		synaptics_i2c_reset_config(touch->client);
404 }
405 
406 /* Control the Device polling rate / Work Handler sleep time */
407 static unsigned long synaptics_i2c_adjust_delay(struct synaptics_i2c *touch,
408 						bool have_data)
409 {
410 	unsigned long delay, nodata_count_thres;
411 
412 	if (polling_req) {
413 		delay = touch->scan_ms;
414 		if (have_data) {
415 			touch->no_data_count = 0;
416 		} else {
417 			nodata_count_thres = NO_DATA_THRES / touch->scan_ms;
418 			if (touch->no_data_count < nodata_count_thres)
419 				touch->no_data_count++;
420 			else
421 				delay = NO_DATA_SLEEP_MSECS;
422 		}
423 		return msecs_to_jiffies(delay);
424 	} else {
425 		delay = msecs_to_jiffies(THREAD_IRQ_SLEEP_MSECS);
426 		return round_jiffies_relative(delay);
427 	}
428 }
429 
430 /* Work Handler */
431 static void synaptics_i2c_work_handler(struct work_struct *work)
432 {
433 	bool have_data;
434 	struct synaptics_i2c *touch =
435 			container_of(work, struct synaptics_i2c, dwork.work);
436 	unsigned long delay;
437 
438 	synaptics_i2c_check_params(touch);
439 
440 	have_data = synaptics_i2c_get_input(touch);
441 	delay = synaptics_i2c_adjust_delay(touch, have_data);
442 
443 	/*
444 	 * While interrupt driven, there is no real need to poll the device.
445 	 * But touchpads are very sensitive, so there could be errors
446 	 * related to physical environment and the attention line isn't
447 	 * necessarily asserted. In such case we can lose the touchpad.
448 	 * We poll the device once in THREAD_IRQ_SLEEP_SECS and
449 	 * if error is detected, we try to reset and reconfigure the touchpad.
450 	 */
451 	mod_delayed_work(system_wq, &touch->dwork, delay);
452 }
453 
454 static int synaptics_i2c_open(struct input_dev *input)
455 {
456 	struct synaptics_i2c *touch = input_get_drvdata(input);
457 	int ret;
458 
459 	ret = synaptics_i2c_reset_config(touch->client);
460 	if (ret)
461 		return ret;
462 
463 	if (polling_req)
464 		mod_delayed_work(system_wq, &touch->dwork,
465 				msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
466 
467 	return 0;
468 }
469 
470 static void synaptics_i2c_close(struct input_dev *input)
471 {
472 	struct synaptics_i2c *touch = input_get_drvdata(input);
473 
474 	if (!polling_req)
475 		synaptics_i2c_reg_set(touch->client, INTERRUPT_EN_REG, 0);
476 
477 	cancel_delayed_work_sync(&touch->dwork);
478 
479 	/* Save some power */
480 	synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP);
481 }
482 
483 static void synaptics_i2c_set_input_params(struct synaptics_i2c *touch)
484 {
485 	struct input_dev *input = touch->input;
486 
487 	input->name = touch->client->name;
488 	input->phys = touch->client->adapter->name;
489 	input->id.bustype = BUS_I2C;
490 	input->id.version = synaptics_i2c_word_get(touch->client,
491 						   INFO_QUERY_REG0);
492 	input->dev.parent = &touch->client->dev;
493 	input->open = synaptics_i2c_open;
494 	input->close = synaptics_i2c_close;
495 	input_set_drvdata(input, touch);
496 
497 	/* Register the device as mouse */
498 	__set_bit(EV_REL, input->evbit);
499 	__set_bit(REL_X, input->relbit);
500 	__set_bit(REL_Y, input->relbit);
501 
502 	/* Register device's buttons and keys */
503 	__set_bit(EV_KEY, input->evbit);
504 	__set_bit(BTN_LEFT, input->keybit);
505 }
506 
507 static struct synaptics_i2c *synaptics_i2c_touch_create(struct i2c_client *client)
508 {
509 	struct synaptics_i2c *touch;
510 
511 	touch = kzalloc(sizeof(struct synaptics_i2c), GFP_KERNEL);
512 	if (!touch)
513 		return NULL;
514 
515 	touch->client = client;
516 	touch->no_decel_param = no_decel;
517 	touch->scan_rate_param = scan_rate;
518 	set_scan_rate(touch, scan_rate);
519 	INIT_DELAYED_WORK(&touch->dwork, synaptics_i2c_work_handler);
520 
521 	return touch;
522 }
523 
524 static int synaptics_i2c_probe(struct i2c_client *client)
525 {
526 	int ret;
527 	struct synaptics_i2c *touch;
528 
529 	touch = synaptics_i2c_touch_create(client);
530 	if (!touch)
531 		return -ENOMEM;
532 
533 	ret = synaptics_i2c_reset_config(client);
534 	if (ret)
535 		goto err_mem_free;
536 
537 	if (client->irq < 1)
538 		polling_req = true;
539 
540 	touch->input = input_allocate_device();
541 	if (!touch->input) {
542 		ret = -ENOMEM;
543 		goto err_mem_free;
544 	}
545 
546 	synaptics_i2c_set_input_params(touch);
547 
548 	if (!polling_req) {
549 		dev_dbg(&touch->client->dev,
550 			 "Requesting IRQ: %d\n", touch->client->irq);
551 
552 		ret = request_irq(touch->client->irq, synaptics_i2c_irq,
553 				  IRQ_TYPE_EDGE_FALLING,
554 				  DRIVER_NAME, touch);
555 		if (ret) {
556 			dev_warn(&touch->client->dev,
557 				  "IRQ request failed: %d, "
558 				  "falling back to polling\n", ret);
559 			polling_req = true;
560 			synaptics_i2c_reg_set(touch->client,
561 					      INTERRUPT_EN_REG, 0);
562 		}
563 	}
564 
565 	if (polling_req)
566 		dev_dbg(&touch->client->dev,
567 			 "Using polling at rate: %d times/sec\n", scan_rate);
568 
569 	/* Register the device in input subsystem */
570 	ret = input_register_device(touch->input);
571 	if (ret) {
572 		dev_err(&client->dev,
573 			 "Input device register failed: %d\n", ret);
574 		goto err_input_free;
575 	}
576 
577 	i2c_set_clientdata(client, touch);
578 
579 	return 0;
580 
581 err_input_free:
582 	input_free_device(touch->input);
583 err_mem_free:
584 	kfree(touch);
585 
586 	return ret;
587 }
588 
589 static void synaptics_i2c_remove(struct i2c_client *client)
590 {
591 	struct synaptics_i2c *touch = i2c_get_clientdata(client);
592 
593 	if (!polling_req)
594 		free_irq(client->irq, touch);
595 
596 	input_unregister_device(touch->input);
597 	kfree(touch);
598 }
599 
600 static int synaptics_i2c_suspend(struct device *dev)
601 {
602 	struct i2c_client *client = to_i2c_client(dev);
603 	struct synaptics_i2c *touch = i2c_get_clientdata(client);
604 
605 	cancel_delayed_work_sync(&touch->dwork);
606 
607 	/* Save some power */
608 	synaptics_i2c_reg_set(touch->client, DEV_CONTROL_REG, DEEP_SLEEP);
609 
610 	return 0;
611 }
612 
613 static int synaptics_i2c_resume(struct device *dev)
614 {
615 	int ret;
616 	struct i2c_client *client = to_i2c_client(dev);
617 	struct synaptics_i2c *touch = i2c_get_clientdata(client);
618 
619 	ret = synaptics_i2c_reset_config(client);
620 	if (ret)
621 		return ret;
622 
623 	mod_delayed_work(system_wq, &touch->dwork,
624 				msecs_to_jiffies(NO_DATA_SLEEP_MSECS));
625 
626 	return 0;
627 }
628 
629 static DEFINE_SIMPLE_DEV_PM_OPS(synaptics_i2c_pm, synaptics_i2c_suspend,
630 				synaptics_i2c_resume);
631 
632 static const struct i2c_device_id synaptics_i2c_id_table[] = {
633 	{ "synaptics_i2c", 0 },
634 	{ },
635 };
636 MODULE_DEVICE_TABLE(i2c, synaptics_i2c_id_table);
637 
638 #ifdef CONFIG_OF
639 static const struct of_device_id synaptics_i2c_of_match[] = {
640 	{ .compatible = "synaptics,synaptics_i2c", },
641 	{ },
642 };
643 MODULE_DEVICE_TABLE(of, synaptics_i2c_of_match);
644 #endif
645 
646 static struct i2c_driver synaptics_i2c_driver = {
647 	.driver = {
648 		.name	= DRIVER_NAME,
649 		.of_match_table = of_match_ptr(synaptics_i2c_of_match),
650 		.pm	= pm_sleep_ptr(&synaptics_i2c_pm),
651 	},
652 
653 	.probe		= synaptics_i2c_probe,
654 	.remove		= synaptics_i2c_remove,
655 
656 	.id_table	= synaptics_i2c_id_table,
657 };
658 
659 module_i2c_driver(synaptics_i2c_driver);
660 
661 MODULE_DESCRIPTION("Synaptics I2C touchpad driver");
662 MODULE_AUTHOR("Mike Rapoport, Igor Grinberg, Compulab");
663 MODULE_LICENSE("GPL");
664 
665