1 /*
2  * Copyright (C) ST-Ericsson SA 2010
3  * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
4  * License terms:GNU General Public License (GPL) version 2
5  */
6 
7 #include <linux/kernel.h>
8 #include <linux/delay.h>
9 #include <linux/interrupt.h>
10 #include <linux/i2c.h>
11 #include <linux/workqueue.h>
12 #include <linux/input.h>
13 #include <linux/input/bu21013.h>
14 #include <linux/slab.h>
15 #include <linux/regulator/consumer.h>
16 #include <linux/module.h>
17 
18 #define PEN_DOWN_INTR	0
19 #define MAX_FINGERS	2
20 #define RESET_DELAY	30
21 #define PENUP_TIMEOUT	(10)
22 #define DELTA_MIN	16
23 #define MASK_BITS	0x03
24 #define SHIFT_8		8
25 #define SHIFT_2		2
26 #define LENGTH_OF_BUFFER	11
27 #define I2C_RETRY_COUNT	5
28 
29 #define BU21013_SENSORS_BTN_0_7_REG	0x70
30 #define BU21013_SENSORS_BTN_8_15_REG	0x71
31 #define BU21013_SENSORS_BTN_16_23_REG	0x72
32 #define BU21013_X1_POS_MSB_REG		0x73
33 #define BU21013_X1_POS_LSB_REG		0x74
34 #define BU21013_Y1_POS_MSB_REG		0x75
35 #define BU21013_Y1_POS_LSB_REG		0x76
36 #define BU21013_X2_POS_MSB_REG		0x77
37 #define BU21013_X2_POS_LSB_REG		0x78
38 #define BU21013_Y2_POS_MSB_REG		0x79
39 #define BU21013_Y2_POS_LSB_REG		0x7A
40 #define BU21013_INT_CLR_REG		0xE8
41 #define BU21013_INT_MODE_REG		0xE9
42 #define BU21013_GAIN_REG		0xEA
43 #define BU21013_OFFSET_MODE_REG		0xEB
44 #define BU21013_XY_EDGE_REG		0xEC
45 #define BU21013_RESET_REG		0xED
46 #define BU21013_CALIB_REG		0xEE
47 #define BU21013_DONE_REG		0xEF
48 #define BU21013_SENSOR_0_7_REG		0xF0
49 #define BU21013_SENSOR_8_15_REG		0xF1
50 #define BU21013_SENSOR_16_23_REG	0xF2
51 #define BU21013_POS_MODE1_REG		0xF3
52 #define BU21013_POS_MODE2_REG		0xF4
53 #define BU21013_CLK_MODE_REG		0xF5
54 #define BU21013_IDLE_REG		0xFA
55 #define BU21013_FILTER_REG		0xFB
56 #define BU21013_TH_ON_REG		0xFC
57 #define BU21013_TH_OFF_REG		0xFD
58 
59 
60 #define BU21013_RESET_ENABLE		0x01
61 
62 #define BU21013_SENSORS_EN_0_7		0x3F
63 #define BU21013_SENSORS_EN_8_15		0xFC
64 #define BU21013_SENSORS_EN_16_23	0x1F
65 
66 #define BU21013_POS_MODE1_0		0x02
67 #define BU21013_POS_MODE1_1		0x04
68 #define BU21013_POS_MODE1_2		0x08
69 
70 #define BU21013_POS_MODE2_ZERO		0x01
71 #define BU21013_POS_MODE2_AVG1		0x02
72 #define BU21013_POS_MODE2_AVG2		0x04
73 #define BU21013_POS_MODE2_EN_XY		0x08
74 #define BU21013_POS_MODE2_EN_RAW	0x10
75 #define BU21013_POS_MODE2_MULTI		0x80
76 
77 #define BU21013_CLK_MODE_DIV		0x01
78 #define BU21013_CLK_MODE_EXT		0x02
79 #define BU21013_CLK_MODE_CALIB		0x80
80 
81 #define BU21013_IDLET_0			0x01
82 #define BU21013_IDLET_1			0x02
83 #define BU21013_IDLET_2			0x04
84 #define BU21013_IDLET_3			0x08
85 #define BU21013_IDLE_INTERMIT_EN	0x10
86 
87 #define BU21013_DELTA_0_6	0x7F
88 #define BU21013_FILTER_EN	0x80
89 
90 #define BU21013_INT_MODE_LEVEL	0x00
91 #define BU21013_INT_MODE_EDGE	0x01
92 
93 #define BU21013_GAIN_0		0x01
94 #define BU21013_GAIN_1		0x02
95 #define BU21013_GAIN_2		0x04
96 
97 #define BU21013_OFFSET_MODE_DEFAULT	0x00
98 #define BU21013_OFFSET_MODE_MOVE	0x01
99 #define BU21013_OFFSET_MODE_DISABLE	0x02
100 
101 #define BU21013_TH_ON_0		0x01
102 #define BU21013_TH_ON_1		0x02
103 #define BU21013_TH_ON_2		0x04
104 #define BU21013_TH_ON_3		0x08
105 #define BU21013_TH_ON_4		0x10
106 #define BU21013_TH_ON_5		0x20
107 #define BU21013_TH_ON_6		0x40
108 #define BU21013_TH_ON_7		0x80
109 #define BU21013_TH_ON_MAX	0xFF
110 
111 #define BU21013_TH_OFF_0	0x01
112 #define BU21013_TH_OFF_1	0x02
113 #define BU21013_TH_OFF_2	0x04
114 #define BU21013_TH_OFF_3	0x08
115 #define BU21013_TH_OFF_4	0x10
116 #define BU21013_TH_OFF_5	0x20
117 #define BU21013_TH_OFF_6	0x40
118 #define BU21013_TH_OFF_7	0x80
119 #define BU21013_TH_OFF_MAX	0xFF
120 
121 #define BU21013_X_EDGE_0	0x01
122 #define BU21013_X_EDGE_1	0x02
123 #define BU21013_X_EDGE_2	0x04
124 #define BU21013_X_EDGE_3	0x08
125 #define BU21013_Y_EDGE_0	0x10
126 #define BU21013_Y_EDGE_1	0x20
127 #define BU21013_Y_EDGE_2	0x40
128 #define BU21013_Y_EDGE_3	0x80
129 
130 #define BU21013_DONE	0x01
131 #define BU21013_NUMBER_OF_X_SENSORS	(6)
132 #define BU21013_NUMBER_OF_Y_SENSORS	(11)
133 
134 #define DRIVER_TP	"bu21013_tp"
135 
136 /**
137  * struct bu21013_ts_data - touch panel data structure
138  * @client: pointer to the i2c client
139  * @wait: variable to wait_queue_head_t structure
140  * @touch_stopped: touch stop flag
141  * @chip: pointer to the touch panel controller
142  * @in_dev: pointer to the input device structure
143  * @intr_pin: interrupt pin value
144  * @regulator: pointer to the Regulator used for touch screen
145  *
146  * Touch panel device data structure
147  */
148 struct bu21013_ts_data {
149 	struct i2c_client *client;
150 	wait_queue_head_t wait;
151 	bool touch_stopped;
152 	const struct bu21013_platform_device *chip;
153 	struct input_dev *in_dev;
154 	unsigned int intr_pin;
155 	struct regulator *regulator;
156 };
157 
158 /**
159  * bu21013_read_block_data(): read the touch co-ordinates
160  * @data: bu21013_ts_data structure pointer
161  * @buf: byte pointer
162  *
163  * Read the touch co-ordinates using i2c read block into buffer
164  * and returns integer.
165  */
166 static int bu21013_read_block_data(struct bu21013_ts_data *data, u8 *buf)
167 {
168 	int ret, i;
169 
170 	for (i = 0; i < I2C_RETRY_COUNT; i++) {
171 		ret = i2c_smbus_read_i2c_block_data
172 			(data->client, BU21013_SENSORS_BTN_0_7_REG,
173 				LENGTH_OF_BUFFER, buf);
174 		if (ret == LENGTH_OF_BUFFER)
175 			return 0;
176 	}
177 	return -EINVAL;
178 }
179 
180 /**
181  * bu21013_do_touch_report(): Get the touch co-ordinates
182  * @data: bu21013_ts_data structure pointer
183  *
184  * Get the touch co-ordinates from touch sensor registers and writes
185  * into device structure and returns integer.
186  */
187 static int bu21013_do_touch_report(struct bu21013_ts_data *data)
188 {
189 	u8	buf[LENGTH_OF_BUFFER];
190 	unsigned int pos_x[2], pos_y[2];
191 	bool	has_x_sensors, has_y_sensors;
192 	int	finger_down_count = 0;
193 	int	i;
194 
195 	if (data == NULL)
196 		return -EINVAL;
197 
198 	if (bu21013_read_block_data(data, buf) < 0)
199 		return -EINVAL;
200 
201 	has_x_sensors = hweight32(buf[0] & BU21013_SENSORS_EN_0_7);
202 	has_y_sensors = hweight32(((buf[1] & BU21013_SENSORS_EN_8_15) |
203 		((buf[2] & BU21013_SENSORS_EN_16_23) << SHIFT_8)) >> SHIFT_2);
204 	if (!has_x_sensors || !has_y_sensors)
205 		return 0;
206 
207 	for (i = 0; i < MAX_FINGERS; i++) {
208 		const u8 *p = &buf[4 * i + 3];
209 		unsigned int x = p[0] << SHIFT_2 | (p[1] & MASK_BITS);
210 		unsigned int y = p[2] << SHIFT_2 | (p[3] & MASK_BITS);
211 		if (x == 0 || y == 0)
212 			continue;
213 		pos_x[finger_down_count] = x;
214 		pos_y[finger_down_count] = y;
215 		finger_down_count++;
216 	}
217 
218 	if (finger_down_count) {
219 		if (finger_down_count == 2 &&
220 		    (abs(pos_x[0] - pos_x[1]) < DELTA_MIN ||
221 		     abs(pos_y[0] - pos_y[1]) < DELTA_MIN)) {
222 			return 0;
223 		}
224 
225 		for (i = 0; i < finger_down_count; i++) {
226 			if (data->chip->x_flip)
227 				pos_x[i] = data->chip->touch_x_max - pos_x[i];
228 			if (data->chip->y_flip)
229 				pos_y[i] = data->chip->touch_y_max - pos_y[i];
230 
231 			input_report_abs(data->in_dev,
232 					 ABS_MT_POSITION_X, pos_x[i]);
233 			input_report_abs(data->in_dev,
234 					 ABS_MT_POSITION_Y, pos_y[i]);
235 			input_mt_sync(data->in_dev);
236 		}
237 	} else
238 		input_mt_sync(data->in_dev);
239 
240 	input_sync(data->in_dev);
241 
242 	return 0;
243 }
244 /**
245  * bu21013_gpio_irq() - gpio thread function for touch interrupt
246  * @irq: irq value
247  * @device_data: void pointer
248  *
249  * This gpio thread function for touch interrupt
250  * and returns irqreturn_t.
251  */
252 static irqreturn_t bu21013_gpio_irq(int irq, void *device_data)
253 {
254 	struct bu21013_ts_data *data = device_data;
255 	struct i2c_client *i2c = data->client;
256 	int retval;
257 
258 	do {
259 		retval = bu21013_do_touch_report(data);
260 		if (retval < 0) {
261 			dev_err(&i2c->dev, "bu21013_do_touch_report failed\n");
262 			return IRQ_NONE;
263 		}
264 
265 		data->intr_pin = data->chip->irq_read_val();
266 		if (data->intr_pin == PEN_DOWN_INTR)
267 			wait_event_timeout(data->wait, data->touch_stopped,
268 					   msecs_to_jiffies(2));
269 	} while (!data->intr_pin && !data->touch_stopped);
270 
271 	return IRQ_HANDLED;
272 }
273 
274 /**
275  * bu21013_init_chip() - power on sequence for the bu21013 controller
276  * @data: device structure pointer
277  *
278  * This function is used to power on
279  * the bu21013 controller and returns integer.
280  */
281 static int bu21013_init_chip(struct bu21013_ts_data *data)
282 {
283 	int retval;
284 	struct i2c_client *i2c = data->client;
285 
286 	retval = i2c_smbus_write_byte_data(i2c, BU21013_RESET_REG,
287 					BU21013_RESET_ENABLE);
288 	if (retval < 0) {
289 		dev_err(&i2c->dev, "BU21013_RESET reg write failed\n");
290 		return retval;
291 	}
292 	msleep(RESET_DELAY);
293 
294 	retval = i2c_smbus_write_byte_data(i2c, BU21013_SENSOR_0_7_REG,
295 					BU21013_SENSORS_EN_0_7);
296 	if (retval < 0) {
297 		dev_err(&i2c->dev, "BU21013_SENSOR_0_7 reg write failed\n");
298 		return retval;
299 	}
300 
301 	retval = i2c_smbus_write_byte_data(i2c, BU21013_SENSOR_8_15_REG,
302 						BU21013_SENSORS_EN_8_15);
303 	if (retval < 0) {
304 		dev_err(&i2c->dev, "BU21013_SENSOR_8_15 reg write failed\n");
305 		return retval;
306 	}
307 
308 	retval = i2c_smbus_write_byte_data(i2c, BU21013_SENSOR_16_23_REG,
309 						BU21013_SENSORS_EN_16_23);
310 	if (retval < 0) {
311 		dev_err(&i2c->dev, "BU21013_SENSOR_16_23 reg write failed\n");
312 		return retval;
313 	}
314 
315 	retval = i2c_smbus_write_byte_data(i2c, BU21013_POS_MODE1_REG,
316 				(BU21013_POS_MODE1_0 | BU21013_POS_MODE1_1));
317 	if (retval < 0) {
318 		dev_err(&i2c->dev, "BU21013_POS_MODE1 reg write failed\n");
319 		return retval;
320 	}
321 
322 	retval = i2c_smbus_write_byte_data(i2c, BU21013_POS_MODE2_REG,
323 			(BU21013_POS_MODE2_ZERO | BU21013_POS_MODE2_AVG1 |
324 			BU21013_POS_MODE2_AVG2 | BU21013_POS_MODE2_EN_RAW |
325 			BU21013_POS_MODE2_MULTI));
326 	if (retval < 0) {
327 		dev_err(&i2c->dev, "BU21013_POS_MODE2 reg write failed\n");
328 		return retval;
329 	}
330 
331 	if (data->chip->ext_clk)
332 		retval = i2c_smbus_write_byte_data(i2c, BU21013_CLK_MODE_REG,
333 			(BU21013_CLK_MODE_EXT | BU21013_CLK_MODE_CALIB));
334 	else
335 		retval = i2c_smbus_write_byte_data(i2c, BU21013_CLK_MODE_REG,
336 			(BU21013_CLK_MODE_DIV | BU21013_CLK_MODE_CALIB));
337 	if (retval < 0) {
338 		dev_err(&i2c->dev, "BU21013_CLK_MODE reg write failed\n");
339 		return retval;
340 	}
341 
342 	retval = i2c_smbus_write_byte_data(i2c, BU21013_IDLE_REG,
343 				(BU21013_IDLET_0 | BU21013_IDLE_INTERMIT_EN));
344 	if (retval < 0) {
345 		dev_err(&i2c->dev, "BU21013_IDLE reg write failed\n");
346 		return retval;
347 	}
348 
349 	retval = i2c_smbus_write_byte_data(i2c, BU21013_INT_MODE_REG,
350 						BU21013_INT_MODE_LEVEL);
351 	if (retval < 0) {
352 		dev_err(&i2c->dev, "BU21013_INT_MODE reg write failed\n");
353 		return retval;
354 	}
355 
356 	retval = i2c_smbus_write_byte_data(i2c, BU21013_FILTER_REG,
357 						(BU21013_DELTA_0_6 |
358 							BU21013_FILTER_EN));
359 	if (retval < 0) {
360 		dev_err(&i2c->dev, "BU21013_FILTER reg write failed\n");
361 		return retval;
362 	}
363 
364 	retval = i2c_smbus_write_byte_data(i2c, BU21013_TH_ON_REG,
365 					BU21013_TH_ON_5);
366 	if (retval < 0) {
367 		dev_err(&i2c->dev, "BU21013_TH_ON reg write failed\n");
368 		return retval;
369 	}
370 
371 	retval = i2c_smbus_write_byte_data(i2c, BU21013_TH_OFF_REG,
372 				BU21013_TH_OFF_4 | BU21013_TH_OFF_3);
373 	if (retval < 0) {
374 		dev_err(&i2c->dev, "BU21013_TH_OFF reg write failed\n");
375 		return retval;
376 	}
377 
378 	retval = i2c_smbus_write_byte_data(i2c, BU21013_GAIN_REG,
379 					(BU21013_GAIN_0 | BU21013_GAIN_1));
380 	if (retval < 0) {
381 		dev_err(&i2c->dev, "BU21013_GAIN reg write failed\n");
382 		return retval;
383 	}
384 
385 	retval = i2c_smbus_write_byte_data(i2c, BU21013_OFFSET_MODE_REG,
386 					BU21013_OFFSET_MODE_DEFAULT);
387 	if (retval < 0) {
388 		dev_err(&i2c->dev, "BU21013_OFFSET_MODE reg write failed\n");
389 		return retval;
390 	}
391 
392 	retval = i2c_smbus_write_byte_data(i2c, BU21013_XY_EDGE_REG,
393 				(BU21013_X_EDGE_0 | BU21013_X_EDGE_2 |
394 				BU21013_Y_EDGE_1 | BU21013_Y_EDGE_3));
395 	if (retval < 0) {
396 		dev_err(&i2c->dev, "BU21013_XY_EDGE reg write failed\n");
397 		return retval;
398 	}
399 
400 	retval = i2c_smbus_write_byte_data(i2c, BU21013_DONE_REG,
401 							BU21013_DONE);
402 	if (retval < 0) {
403 		dev_err(&i2c->dev, "BU21013_REG_DONE reg write failed\n");
404 		return retval;
405 	}
406 
407 	return 0;
408 }
409 
410 /**
411  * bu21013_free_irq() - frees IRQ registered for touchscreen
412  * @bu21013_data: device structure pointer
413  *
414  * This function signals interrupt thread to stop processing and
415  * frees interrupt.
416  */
417 static void bu21013_free_irq(struct bu21013_ts_data *bu21013_data)
418 {
419 	bu21013_data->touch_stopped = true;
420 	wake_up(&bu21013_data->wait);
421 	free_irq(bu21013_data->chip->irq, bu21013_data);
422 }
423 
424 /**
425  * bu21013_probe() - initializes the i2c-client touchscreen driver
426  * @client: i2c client structure pointer
427  * @id: i2c device id pointer
428  *
429  * This function used to initializes the i2c-client touchscreen
430  * driver and returns integer.
431  */
432 static int __devinit bu21013_probe(struct i2c_client *client,
433 					const struct i2c_device_id *id)
434 {
435 	struct bu21013_ts_data *bu21013_data;
436 	struct input_dev *in_dev;
437 	const struct bu21013_platform_device *pdata =
438 					client->dev.platform_data;
439 	int error;
440 
441 	if (!i2c_check_functionality(client->adapter,
442 					I2C_FUNC_SMBUS_BYTE_DATA)) {
443 		dev_err(&client->dev, "i2c smbus byte data not supported\n");
444 		return -EIO;
445 	}
446 
447 	if (!pdata) {
448 		dev_err(&client->dev, "platform data not defined\n");
449 		return -EINVAL;
450 	}
451 
452 	bu21013_data = kzalloc(sizeof(struct bu21013_ts_data), GFP_KERNEL);
453 	in_dev = input_allocate_device();
454 	if (!bu21013_data || !in_dev) {
455 		dev_err(&client->dev, "device memory alloc failed\n");
456 		error = -ENOMEM;
457 		goto err_free_mem;
458 	}
459 
460 	bu21013_data->in_dev = in_dev;
461 	bu21013_data->chip = pdata;
462 	bu21013_data->client = client;
463 
464 	bu21013_data->regulator = regulator_get(&client->dev, "V-TOUCH");
465 	if (IS_ERR(bu21013_data->regulator)) {
466 		dev_err(&client->dev, "regulator_get failed\n");
467 		error = PTR_ERR(bu21013_data->regulator);
468 		goto err_free_mem;
469 	}
470 
471 	error = regulator_enable(bu21013_data->regulator);
472 	if (error < 0) {
473 		dev_err(&client->dev, "regulator enable failed\n");
474 		goto err_put_regulator;
475 	}
476 
477 	bu21013_data->touch_stopped = false;
478 	init_waitqueue_head(&bu21013_data->wait);
479 
480 	/* configure the gpio pins */
481 	if (pdata->cs_en) {
482 		error = pdata->cs_en(pdata->cs_pin);
483 		if (error < 0) {
484 			dev_err(&client->dev, "chip init failed\n");
485 			goto err_disable_regulator;
486 		}
487 	}
488 
489 	/* configure the touch panel controller */
490 	error = bu21013_init_chip(bu21013_data);
491 	if (error) {
492 		dev_err(&client->dev, "error in bu21013 config\n");
493 		goto err_cs_disable;
494 	}
495 
496 	/* register the device to input subsystem */
497 	in_dev->name = DRIVER_TP;
498 	in_dev->id.bustype = BUS_I2C;
499 	in_dev->dev.parent = &client->dev;
500 
501 	__set_bit(EV_SYN, in_dev->evbit);
502 	__set_bit(EV_KEY, in_dev->evbit);
503 	__set_bit(EV_ABS, in_dev->evbit);
504 
505 	input_set_abs_params(in_dev, ABS_MT_POSITION_X, 0,
506 						pdata->touch_x_max, 0, 0);
507 	input_set_abs_params(in_dev, ABS_MT_POSITION_Y, 0,
508 						pdata->touch_y_max, 0, 0);
509 	input_set_drvdata(in_dev, bu21013_data);
510 
511 	error = request_threaded_irq(pdata->irq, NULL, bu21013_gpio_irq,
512 				     IRQF_TRIGGER_FALLING | IRQF_SHARED,
513 				     DRIVER_TP, bu21013_data);
514 	if (error) {
515 		dev_err(&client->dev, "request irq %d failed\n", pdata->irq);
516 		goto err_cs_disable;
517 	}
518 
519 	error = input_register_device(in_dev);
520 	if (error) {
521 		dev_err(&client->dev, "failed to register input device\n");
522 		goto err_free_irq;
523 	}
524 
525 	device_init_wakeup(&client->dev, pdata->wakeup);
526 	i2c_set_clientdata(client, bu21013_data);
527 
528 	return 0;
529 
530 err_free_irq:
531 	bu21013_free_irq(bu21013_data);
532 err_cs_disable:
533 	pdata->cs_dis(pdata->cs_pin);
534 err_disable_regulator:
535 	regulator_disable(bu21013_data->regulator);
536 err_put_regulator:
537 	regulator_put(bu21013_data->regulator);
538 err_free_mem:
539 	input_free_device(in_dev);
540 	kfree(bu21013_data);
541 
542 	return error;
543 }
544 /**
545  * bu21013_remove() - removes the i2c-client touchscreen driver
546  * @client: i2c client structure pointer
547  *
548  * This function uses to remove the i2c-client
549  * touchscreen driver and returns integer.
550  */
551 static int __devexit bu21013_remove(struct i2c_client *client)
552 {
553 	struct bu21013_ts_data *bu21013_data = i2c_get_clientdata(client);
554 
555 	bu21013_free_irq(bu21013_data);
556 
557 	bu21013_data->chip->cs_dis(bu21013_data->chip->cs_pin);
558 
559 	input_unregister_device(bu21013_data->in_dev);
560 
561 	regulator_disable(bu21013_data->regulator);
562 	regulator_put(bu21013_data->regulator);
563 
564 	kfree(bu21013_data);
565 
566 	device_init_wakeup(&client->dev, false);
567 
568 	return 0;
569 }
570 
571 #ifdef CONFIG_PM
572 /**
573  * bu21013_suspend() - suspend the touch screen controller
574  * @dev: pointer to device structure
575  *
576  * This function is used to suspend the
577  * touch panel controller and returns integer
578  */
579 static int bu21013_suspend(struct device *dev)
580 {
581 	struct bu21013_ts_data *bu21013_data = dev_get_drvdata(dev);
582 	struct i2c_client *client = bu21013_data->client;
583 
584 	bu21013_data->touch_stopped = true;
585 	if (device_may_wakeup(&client->dev))
586 		enable_irq_wake(bu21013_data->chip->irq);
587 	else
588 		disable_irq(bu21013_data->chip->irq);
589 
590 	regulator_disable(bu21013_data->regulator);
591 
592 	return 0;
593 }
594 
595 /**
596  * bu21013_resume() - resume the touch screen controller
597  * @dev: pointer to device structure
598  *
599  * This function is used to resume the touch panel
600  * controller and returns integer.
601  */
602 static int bu21013_resume(struct device *dev)
603 {
604 	struct bu21013_ts_data *bu21013_data = dev_get_drvdata(dev);
605 	struct i2c_client *client = bu21013_data->client;
606 	int retval;
607 
608 	retval = regulator_enable(bu21013_data->regulator);
609 	if (retval < 0) {
610 		dev_err(&client->dev, "bu21013 regulator enable failed\n");
611 		return retval;
612 	}
613 
614 	retval = bu21013_init_chip(bu21013_data);
615 	if (retval < 0) {
616 		dev_err(&client->dev, "bu21013 controller config failed\n");
617 		return retval;
618 	}
619 
620 	bu21013_data->touch_stopped = false;
621 
622 	if (device_may_wakeup(&client->dev))
623 		disable_irq_wake(bu21013_data->chip->irq);
624 	else
625 		enable_irq(bu21013_data->chip->irq);
626 
627 	return 0;
628 }
629 
630 static const struct dev_pm_ops bu21013_dev_pm_ops = {
631 	.suspend = bu21013_suspend,
632 	.resume  = bu21013_resume,
633 };
634 #endif
635 
636 static const struct i2c_device_id bu21013_id[] = {
637 	{ DRIVER_TP, 0 },
638 	{ }
639 };
640 MODULE_DEVICE_TABLE(i2c, bu21013_id);
641 
642 static struct i2c_driver bu21013_driver = {
643 	.driver	= {
644 		.name	=	DRIVER_TP,
645 		.owner	=	THIS_MODULE,
646 #ifdef CONFIG_PM
647 		.pm	=	&bu21013_dev_pm_ops,
648 #endif
649 	},
650 	.probe		=	bu21013_probe,
651 	.remove		=	__devexit_p(bu21013_remove),
652 	.id_table	=	bu21013_id,
653 };
654 
655 module_i2c_driver(bu21013_driver);
656 
657 MODULE_LICENSE("GPL v2");
658 MODULE_AUTHOR("Naveen Kumar G <naveen.gaddipati@stericsson.com>");
659 MODULE_DESCRIPTION("bu21013 touch screen controller driver");
660