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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#include <linux/gpio.h>
18#include <linux/of.h>
19#include <linux/of_gpio.h>
20
21#define PEN_DOWN_INTR 0
22#define MAX_FINGERS 2
23#define RESET_DELAY 30
24#define PENUP_TIMEOUT (10)
25#define DELTA_MIN 16
26#define MASK_BITS 0x03
27#define SHIFT_8 8
28#define SHIFT_2 2
29#define LENGTH_OF_BUFFER 11
30#define I2C_RETRY_COUNT 5
31
32#define BU21013_SENSORS_BTN_0_7_REG 0x70
33#define BU21013_SENSORS_BTN_8_15_REG 0x71
34#define BU21013_SENSORS_BTN_16_23_REG 0x72
35#define BU21013_X1_POS_MSB_REG 0x73
36#define BU21013_X1_POS_LSB_REG 0x74
37#define BU21013_Y1_POS_MSB_REG 0x75
38#define BU21013_Y1_POS_LSB_REG 0x76
39#define BU21013_X2_POS_MSB_REG 0x77
40#define BU21013_X2_POS_LSB_REG 0x78
41#define BU21013_Y2_POS_MSB_REG 0x79
42#define BU21013_Y2_POS_LSB_REG 0x7A
43#define BU21013_INT_CLR_REG 0xE8
44#define BU21013_INT_MODE_REG 0xE9
45#define BU21013_GAIN_REG 0xEA
46#define BU21013_OFFSET_MODE_REG 0xEB
47#define BU21013_XY_EDGE_REG 0xEC
48#define BU21013_RESET_REG 0xED
49#define BU21013_CALIB_REG 0xEE
50#define BU21013_DONE_REG 0xEF
51#define BU21013_SENSOR_0_7_REG 0xF0
52#define BU21013_SENSOR_8_15_REG 0xF1
53#define BU21013_SENSOR_16_23_REG 0xF2
54#define BU21013_POS_MODE1_REG 0xF3
55#define BU21013_POS_MODE2_REG 0xF4
56#define BU21013_CLK_MODE_REG 0xF5
57#define BU21013_IDLE_REG 0xFA
58#define BU21013_FILTER_REG 0xFB
59#define BU21013_TH_ON_REG 0xFC
60#define BU21013_TH_OFF_REG 0xFD
61
62
63#define BU21013_RESET_ENABLE 0x01
64
65#define BU21013_SENSORS_EN_0_7 0x3F
66#define BU21013_SENSORS_EN_8_15 0xFC
67#define BU21013_SENSORS_EN_16_23 0x1F
68
69#define BU21013_POS_MODE1_0 0x02
70#define BU21013_POS_MODE1_1 0x04
71#define BU21013_POS_MODE1_2 0x08
72
73#define BU21013_POS_MODE2_ZERO 0x01
74#define BU21013_POS_MODE2_AVG1 0x02
75#define BU21013_POS_MODE2_AVG2 0x04
76#define BU21013_POS_MODE2_EN_XY 0x08
77#define BU21013_POS_MODE2_EN_RAW 0x10
78#define BU21013_POS_MODE2_MULTI 0x80
79
80#define BU21013_CLK_MODE_DIV 0x01
81#define BU21013_CLK_MODE_EXT 0x02
82#define BU21013_CLK_MODE_CALIB 0x80
83
84#define BU21013_IDLET_0 0x01
85#define BU21013_IDLET_1 0x02
86#define BU21013_IDLET_2 0x04
87#define BU21013_IDLET_3 0x08
88#define BU21013_IDLE_INTERMIT_EN 0x10
89
90#define BU21013_DELTA_0_6 0x7F
91#define BU21013_FILTER_EN 0x80
92
93#define BU21013_INT_MODE_LEVEL 0x00
94#define BU21013_INT_MODE_EDGE 0x01
95
96#define BU21013_GAIN_0 0x01
97#define BU21013_GAIN_1 0x02
98#define BU21013_GAIN_2 0x04
99
100#define BU21013_OFFSET_MODE_DEFAULT 0x00
101#define BU21013_OFFSET_MODE_MOVE 0x01
102#define BU21013_OFFSET_MODE_DISABLE 0x02
103
104#define BU21013_TH_ON_0 0x01
105#define BU21013_TH_ON_1 0x02
106#define BU21013_TH_ON_2 0x04
107#define BU21013_TH_ON_3 0x08
108#define BU21013_TH_ON_4 0x10
109#define BU21013_TH_ON_5 0x20
110#define BU21013_TH_ON_6 0x40
111#define BU21013_TH_ON_7 0x80
112#define BU21013_TH_ON_MAX 0xFF
113
114#define BU21013_TH_OFF_0 0x01
115#define BU21013_TH_OFF_1 0x02
116#define BU21013_TH_OFF_2 0x04
117#define BU21013_TH_OFF_3 0x08
118#define BU21013_TH_OFF_4 0x10
119#define BU21013_TH_OFF_5 0x20
120#define BU21013_TH_OFF_6 0x40
121#define BU21013_TH_OFF_7 0x80
122#define BU21013_TH_OFF_MAX 0xFF
123
124#define BU21013_X_EDGE_0 0x01
125#define BU21013_X_EDGE_1 0x02
126#define BU21013_X_EDGE_2 0x04
127#define BU21013_X_EDGE_3 0x08
128#define BU21013_Y_EDGE_0 0x10
129#define BU21013_Y_EDGE_1 0x20
130#define BU21013_Y_EDGE_2 0x40
131#define BU21013_Y_EDGE_3 0x80
132
133#define BU21013_DONE 0x01
134#define BU21013_NUMBER_OF_X_SENSORS (6)
135#define BU21013_NUMBER_OF_Y_SENSORS (11)
136
137#define DRIVER_TP "bu21013_tp"
138
139/**
140 * struct bu21013_ts_data - touch panel data structure
141 * @client: pointer to the i2c client
142 * @wait: variable to wait_queue_head_t structure
143 * @touch_stopped: touch stop flag
144 * @chip: pointer to the touch panel controller
145 * @in_dev: pointer to the input device structure
146 * @intr_pin: interrupt pin value
147 * @regulator: pointer to the Regulator used for touch screen
148 *
149 * Touch panel device data structure
150 */
151struct bu21013_ts_data {
152 struct i2c_client *client;
153 wait_queue_head_t wait;
154 const struct bu21013_platform_device *chip;
155 struct input_dev *in_dev;
156 struct regulator *regulator;
157 unsigned int irq;
158 unsigned int intr_pin;
159 bool touch_stopped;
160};
161
162/**
163 * bu21013_read_block_data(): read the touch co-ordinates
164 * @data: bu21013_ts_data structure pointer
165 * @buf: byte pointer
166 *
167 * Read the touch co-ordinates using i2c read block into buffer
168 * and returns integer.
169 */
170static int bu21013_read_block_data(struct bu21013_ts_data *data, u8 *buf)
171{
172 int ret, i;
173
174 for (i = 0; i < I2C_RETRY_COUNT; i++) {
175 ret = i2c_smbus_read_i2c_block_data
176 (data->client, BU21013_SENSORS_BTN_0_7_REG,
177 LENGTH_OF_BUFFER, buf);
178 if (ret == LENGTH_OF_BUFFER)
179 return 0;
180 }
181 return -EINVAL;
182}
183
184/**
185 * bu21013_do_touch_report(): Get the touch co-ordinates
186 * @data: bu21013_ts_data structure pointer
187 *
188 * Get the touch co-ordinates from touch sensor registers and writes
189 * into device structure and returns integer.
190 */
191static int bu21013_do_touch_report(struct bu21013_ts_data *data)
192{
193 u8 buf[LENGTH_OF_BUFFER];
194 unsigned int pos_x[2], pos_y[2];
195 bool has_x_sensors, has_y_sensors;
196 int finger_down_count = 0;
197 int i;
198
199 if (data == NULL)
200 return -EINVAL;
201
202 if (bu21013_read_block_data(data, buf) < 0)
203 return -EINVAL;
204
205 has_x_sensors = hweight32(buf[0] & BU21013_SENSORS_EN_0_7);
206 has_y_sensors = hweight32(((buf[1] & BU21013_SENSORS_EN_8_15) |
207 ((buf[2] & BU21013_SENSORS_EN_16_23) << SHIFT_8)) >> SHIFT_2);
208 if (!has_x_sensors || !has_y_sensors)
209 return 0;
210
211 for (i = 0; i < MAX_FINGERS; i++) {
212 const u8 *p = &buf[4 * i + 3];
213 unsigned int x = p[0] << SHIFT_2 | (p[1] & MASK_BITS);
214 unsigned int y = p[2] << SHIFT_2 | (p[3] & MASK_BITS);
215 if (x == 0 || y == 0)
216 continue;
217 pos_x[finger_down_count] = x;
218 pos_y[finger_down_count] = y;
219 finger_down_count++;
220 }
221
222 if (finger_down_count) {
223 if (finger_down_count == 2 &&
224 (abs(pos_x[0] - pos_x[1]) < DELTA_MIN ||
225 abs(pos_y[0] - pos_y[1]) < DELTA_MIN)) {
226 return 0;
227 }
228
229 for (i = 0; i < finger_down_count; i++) {
230 if (data->chip->x_flip)
231 pos_x[i] = data->chip->touch_x_max - pos_x[i];
232 if (data->chip->y_flip)
233 pos_y[i] = data->chip->touch_y_max - pos_y[i];
234
235 input_report_abs(data->in_dev,
236 ABS_MT_POSITION_X, pos_x[i]);
237 input_report_abs(data->in_dev,
238 ABS_MT_POSITION_Y, pos_y[i]);
239 input_mt_sync(data->in_dev);
240 }
241 } else
242 input_mt_sync(data->in_dev);
243
244 input_sync(data->in_dev);
245
246 return 0;
247}
248/**
249 * bu21013_gpio_irq() - gpio thread function for touch interrupt
250 * @irq: irq value
251 * @device_data: void pointer
252 *
253 * This gpio thread function for touch interrupt
254 * and returns irqreturn_t.
255 */
256static irqreturn_t bu21013_gpio_irq(int irq, void *device_data)
257{
258 struct bu21013_ts_data *data = device_data;
259 struct i2c_client *i2c = data->client;
260 int retval;
261
262 do {
263 retval = bu21013_do_touch_report(data);
264 if (retval < 0) {
265 dev_err(&i2c->dev, "bu21013_do_touch_report failed\n");
266 return IRQ_NONE;
267 }
268
269 data->intr_pin = gpio_get_value(data->chip->touch_pin);
270 if (data->intr_pin == PEN_DOWN_INTR)
271 wait_event_timeout(data->wait, data->touch_stopped,
272 msecs_to_jiffies(2));
273 } while (!data->intr_pin && !data->touch_stopped);
274
275 return IRQ_HANDLED;
276}
277
278/**
279 * bu21013_init_chip() - power on sequence for the bu21013 controller
280 * @data: device structure pointer
281 *
282 * This function is used to power on
283 * the bu21013 controller and returns integer.
284 */
285static int bu21013_init_chip(struct bu21013_ts_data *data)
286{
287 int retval;
288 struct i2c_client *i2c = data->client;
289
290 retval = i2c_smbus_write_byte_data(i2c, BU21013_RESET_REG,
291 BU21013_RESET_ENABLE);
292 if (retval < 0) {
293 dev_err(&i2c->dev, "BU21013_RESET reg write failed\n");
294 return retval;
295 }
296 msleep(RESET_DELAY);
297
298 retval = i2c_smbus_write_byte_data(i2c, BU21013_SENSOR_0_7_REG,
299 BU21013_SENSORS_EN_0_7);
300 if (retval < 0) {
301 dev_err(&i2c->dev, "BU21013_SENSOR_0_7 reg write failed\n");
302 return retval;
303 }
304
305 retval = i2c_smbus_write_byte_data(i2c, BU21013_SENSOR_8_15_REG,
306 BU21013_SENSORS_EN_8_15);
307 if (retval < 0) {
308 dev_err(&i2c->dev, "BU21013_SENSOR_8_15 reg write failed\n");
309 return retval;
310 }
311
312 retval = i2c_smbus_write_byte_data(i2c, BU21013_SENSOR_16_23_REG,
313 BU21013_SENSORS_EN_16_23);
314 if (retval < 0) {
315 dev_err(&i2c->dev, "BU21013_SENSOR_16_23 reg write failed\n");
316 return retval;
317 }
318
319 retval = i2c_smbus_write_byte_data(i2c, BU21013_POS_MODE1_REG,
320 (BU21013_POS_MODE1_0 | BU21013_POS_MODE1_1));
321 if (retval < 0) {
322 dev_err(&i2c->dev, "BU21013_POS_MODE1 reg write failed\n");
323 return retval;
324 }
325
326 retval = i2c_smbus_write_byte_data(i2c, BU21013_POS_MODE2_REG,
327 (BU21013_POS_MODE2_ZERO | BU21013_POS_MODE2_AVG1 |
328 BU21013_POS_MODE2_AVG2 | BU21013_POS_MODE2_EN_RAW |
329 BU21013_POS_MODE2_MULTI));
330 if (retval < 0) {
331 dev_err(&i2c->dev, "BU21013_POS_MODE2 reg write failed\n");
332 return retval;
333 }
334
335 if (data->chip->ext_clk)
336 retval = i2c_smbus_write_byte_data(i2c, BU21013_CLK_MODE_REG,
337 (BU21013_CLK_MODE_EXT | BU21013_CLK_MODE_CALIB));
338 else
339 retval = i2c_smbus_write_byte_data(i2c, BU21013_CLK_MODE_REG,
340 (BU21013_CLK_MODE_DIV | BU21013_CLK_MODE_CALIB));
341 if (retval < 0) {
342 dev_err(&i2c->dev, "BU21013_CLK_MODE reg write failed\n");
343 return retval;
344 }
345
346 retval = i2c_smbus_write_byte_data(i2c, BU21013_IDLE_REG,
347 (BU21013_IDLET_0 | BU21013_IDLE_INTERMIT_EN));
348 if (retval < 0) {
349 dev_err(&i2c->dev, "BU21013_IDLE reg write failed\n");
350 return retval;
351 }
352
353 retval = i2c_smbus_write_byte_data(i2c, BU21013_INT_MODE_REG,
354 BU21013_INT_MODE_LEVEL);
355 if (retval < 0) {
356 dev_err(&i2c->dev, "BU21013_INT_MODE reg write failed\n");
357 return retval;
358 }
359
360 retval = i2c_smbus_write_byte_data(i2c, BU21013_FILTER_REG,
361 (BU21013_DELTA_0_6 |
362 BU21013_FILTER_EN));
363 if (retval < 0) {
364 dev_err(&i2c->dev, "BU21013_FILTER reg write failed\n");
365 return retval;
366 }
367
368 retval = i2c_smbus_write_byte_data(i2c, BU21013_TH_ON_REG,
369 BU21013_TH_ON_5);
370 if (retval < 0) {
371 dev_err(&i2c->dev, "BU21013_TH_ON reg write failed\n");
372 return retval;
373 }
374
375 retval = i2c_smbus_write_byte_data(i2c, BU21013_TH_OFF_REG,
376 BU21013_TH_OFF_4 | BU21013_TH_OFF_3);
377 if (retval < 0) {
378 dev_err(&i2c->dev, "BU21013_TH_OFF reg write failed\n");
379 return retval;
380 }
381
382 retval = i2c_smbus_write_byte_data(i2c, BU21013_GAIN_REG,
383 (BU21013_GAIN_0 | BU21013_GAIN_1));
384 if (retval < 0) {
385 dev_err(&i2c->dev, "BU21013_GAIN reg write failed\n");
386 return retval;
387 }
388
389 retval = i2c_smbus_write_byte_data(i2c, BU21013_OFFSET_MODE_REG,
390 BU21013_OFFSET_MODE_DEFAULT);
391 if (retval < 0) {
392 dev_err(&i2c->dev, "BU21013_OFFSET_MODE reg write failed\n");
393 return retval;
394 }
395
396 retval = i2c_smbus_write_byte_data(i2c, BU21013_XY_EDGE_REG,
397 (BU21013_X_EDGE_0 | BU21013_X_EDGE_2 |
398 BU21013_Y_EDGE_1 | BU21013_Y_EDGE_3));
399 if (retval < 0) {
400 dev_err(&i2c->dev, "BU21013_XY_EDGE reg write failed\n");
401 return retval;
402 }
403
404 retval = i2c_smbus_write_byte_data(i2c, BU21013_DONE_REG,
405 BU21013_DONE);
406 if (retval < 0) {
407 dev_err(&i2c->dev, "BU21013_REG_DONE reg write failed\n");
408 return retval;
409 }
410
411 return 0;
412}
413
414/**
415 * bu21013_free_irq() - frees IRQ registered for touchscreen
416 * @bu21013_data: device structure pointer
417 *
418 * This function signals interrupt thread to stop processing and
419 * frees interrupt.
420 */
421static void bu21013_free_irq(struct bu21013_ts_data *bu21013_data)
422{
423 bu21013_data->touch_stopped = true;
424 wake_up(&bu21013_data->wait);
425 free_irq(bu21013_data->irq, bu21013_data);
426}
427
428/**
429 * bu21013_cs_disable() - deconfigures the touch panel controller
430 * @bu21013_data: device structure pointer
431 *
432 * This function is used to deconfigure the chip selection
433 * for touch panel controller.
434 */
435static void bu21013_cs_disable(struct bu21013_ts_data *bu21013_data)
436{
437 int error;
438
439 error = gpio_direction_output(bu21013_data->chip->cs_pin, 0);
440 if (error < 0)
441 dev_warn(&bu21013_data->client->dev,
442 "%s: gpio direction failed, error: %d\n",
443 __func__, error);
444 else
445 gpio_set_value(bu21013_data->chip->cs_pin, 0);
446
447 gpio_free(bu21013_data->chip->cs_pin);
448}
449
450#ifdef CONFIG_OF
451static const struct bu21013_platform_device *
452bu21013_parse_dt(struct device *dev)
453{
454 struct device_node *np = dev->of_node;
455 struct bu21013_platform_device *pdata;
456
457 if (!np) {
458 dev_err(dev, "no device tree or platform data\n");
459 return ERR_PTR(-EINVAL);
460 }
461
462 pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
463 if (!pdata)
464 return ERR_PTR(-ENOMEM);
465
466 pdata->y_flip = pdata->x_flip = false;
467
468 pdata->x_flip = of_property_read_bool(np, "rohm,flip-x");
469 pdata->y_flip = of_property_read_bool(np, "rohm,flip-y");
470
471 of_property_read_u32(np, "rohm,touch-max-x", &pdata->touch_x_max);
472 of_property_read_u32(np, "rohm,touch-max-y", &pdata->touch_y_max);
473
474 pdata->touch_pin = of_get_named_gpio(np, "touch-gpio", 0);
475 pdata->cs_pin = of_get_named_gpio(np, "reset-gpio", 0);
476
477 pdata->ext_clk = false;
478
479 return pdata;
480}
481#else
482static inline const struct bu21013_platform_device *
483bu21013_parse_dt(struct device *dev)
484{
485 dev_err(dev, "no platform data available\n");
486 return ERR_PTR(-EINVAL);
487}
488#endif
489
490/**
491 * bu21013_probe() - initializes the i2c-client touchscreen driver
492 * @client: i2c client structure pointer
493 * @id: i2c device id pointer
494 *
495 * This function used to initializes the i2c-client touchscreen
496 * driver and returns integer.
497 */
498static int bu21013_probe(struct i2c_client *client,
499 const struct i2c_device_id *id)
500{
501 const struct bu21013_platform_device *pdata =
502 dev_get_platdata(&client->dev);
503 struct bu21013_ts_data *bu21013_data;
504 struct input_dev *in_dev;
505 int error;
506
507 if (!i2c_check_functionality(client->adapter,
508 I2C_FUNC_SMBUS_BYTE_DATA)) {
509 dev_err(&client->dev, "i2c smbus byte data not supported\n");
510 return -EIO;
511 }
512
513 if (!pdata) {
514 pdata = bu21013_parse_dt(&client->dev);
515 if (IS_ERR(pdata))
516 return PTR_ERR(pdata);
517 }
518
519 if (!gpio_is_valid(pdata->touch_pin)) {
520 dev_err(&client->dev, "invalid touch_pin supplied\n");
521 return -EINVAL;
522 }
523
524 bu21013_data = kzalloc(sizeof(struct bu21013_ts_data), GFP_KERNEL);
525 in_dev = input_allocate_device();
526 if (!bu21013_data || !in_dev) {
527 dev_err(&client->dev, "device memory alloc failed\n");
528 error = -ENOMEM;
529 goto err_free_mem;
530 }
531
532 bu21013_data->in_dev = in_dev;
533 bu21013_data->chip = pdata;
534 bu21013_data->client = client;
535 bu21013_data->irq = gpio_to_irq(pdata->touch_pin);
536
537 bu21013_data->regulator = regulator_get(&client->dev, "avdd");
538 if (IS_ERR(bu21013_data->regulator)) {
539 dev_err(&client->dev, "regulator_get failed\n");
540 error = PTR_ERR(bu21013_data->regulator);
541 goto err_free_mem;
542 }
543
544 error = regulator_enable(bu21013_data->regulator);
545 if (error < 0) {
546 dev_err(&client->dev, "regulator enable failed\n");
547 goto err_put_regulator;
548 }
549
550 bu21013_data->touch_stopped = false;
551 init_waitqueue_head(&bu21013_data->wait);
552
553 /* configure the gpio pins */
554 error = gpio_request_one(pdata->cs_pin, GPIOF_OUT_INIT_HIGH,
555 "touchp_reset");
556 if (error < 0) {
557 dev_err(&client->dev, "Unable to request gpio reset_pin\n");
558 goto err_disable_regulator;
559 }
560
561 /* configure the touch panel controller */
562 error = bu21013_init_chip(bu21013_data);
563 if (error) {
564 dev_err(&client->dev, "error in bu21013 config\n");
565 goto err_cs_disable;
566 }
567
568 /* register the device to input subsystem */
569 in_dev->name = DRIVER_TP;
570 in_dev->id.bustype = BUS_I2C;
571 in_dev->dev.parent = &client->dev;
572
573 __set_bit(EV_SYN, in_dev->evbit);
574 __set_bit(EV_KEY, in_dev->evbit);
575 __set_bit(EV_ABS, in_dev->evbit);
576
577 input_set_abs_params(in_dev, ABS_MT_POSITION_X, 0,
578 pdata->touch_x_max, 0, 0);
579 input_set_abs_params(in_dev, ABS_MT_POSITION_Y, 0,
580 pdata->touch_y_max, 0, 0);
581 input_set_drvdata(in_dev, bu21013_data);
582
583 error = request_threaded_irq(bu21013_data->irq, NULL, bu21013_gpio_irq,
584 IRQF_TRIGGER_FALLING | IRQF_SHARED |
585 IRQF_ONESHOT,
586 DRIVER_TP, bu21013_data);
587 if (error) {
588 dev_err(&client->dev, "request irq %d failed\n",
589 bu21013_data->irq);
590 goto err_cs_disable;
591 }
592
593 error = input_register_device(in_dev);
594 if (error) {
595 dev_err(&client->dev, "failed to register input device\n");
596 goto err_free_irq;
597 }
598
599 device_init_wakeup(&client->dev, pdata->wakeup);
600 i2c_set_clientdata(client, bu21013_data);
601
602 return 0;
603
604err_free_irq:
605 bu21013_free_irq(bu21013_data);
606err_cs_disable:
607 bu21013_cs_disable(bu21013_data);
608err_disable_regulator:
609 regulator_disable(bu21013_data->regulator);
610err_put_regulator:
611 regulator_put(bu21013_data->regulator);
612err_free_mem:
613 input_free_device(in_dev);
614 kfree(bu21013_data);
615
616 return error;
617}
618/**
619 * bu21013_remove() - removes the i2c-client touchscreen driver
620 * @client: i2c client structure pointer
621 *
622 * This function uses to remove the i2c-client
623 * touchscreen driver and returns integer.
624 */
625static int bu21013_remove(struct i2c_client *client)
626{
627 struct bu21013_ts_data *bu21013_data = i2c_get_clientdata(client);
628
629 bu21013_free_irq(bu21013_data);
630
631 bu21013_cs_disable(bu21013_data);
632
633 input_unregister_device(bu21013_data->in_dev);
634
635 regulator_disable(bu21013_data->regulator);
636 regulator_put(bu21013_data->regulator);
637
638 kfree(bu21013_data);
639
640 device_init_wakeup(&client->dev, false);
641
642 return 0;
643}
644
645#ifdef CONFIG_PM
646/**
647 * bu21013_suspend() - suspend the touch screen controller
648 * @dev: pointer to device structure
649 *
650 * This function is used to suspend the
651 * touch panel controller and returns integer
652 */
653static int bu21013_suspend(struct device *dev)
654{
655 struct bu21013_ts_data *bu21013_data = dev_get_drvdata(dev);
656 struct i2c_client *client = bu21013_data->client;
657
658 bu21013_data->touch_stopped = true;
659 if (device_may_wakeup(&client->dev))
660 enable_irq_wake(bu21013_data->irq);
661 else
662 disable_irq(bu21013_data->irq);
663
664 regulator_disable(bu21013_data->regulator);
665
666 return 0;
667}
668
669/**
670 * bu21013_resume() - resume the touch screen controller
671 * @dev: pointer to device structure
672 *
673 * This function is used to resume the touch panel
674 * controller and returns integer.
675 */
676static int bu21013_resume(struct device *dev)
677{
678 struct bu21013_ts_data *bu21013_data = dev_get_drvdata(dev);
679 struct i2c_client *client = bu21013_data->client;
680 int retval;
681
682 retval = regulator_enable(bu21013_data->regulator);
683 if (retval < 0) {
684 dev_err(&client->dev, "bu21013 regulator enable failed\n");
685 return retval;
686 }
687
688 retval = bu21013_init_chip(bu21013_data);
689 if (retval < 0) {
690 dev_err(&client->dev, "bu21013 controller config failed\n");
691 return retval;
692 }
693
694 bu21013_data->touch_stopped = false;
695
696 if (device_may_wakeup(&client->dev))
697 disable_irq_wake(bu21013_data->irq);
698 else
699 enable_irq(bu21013_data->irq);
700
701 return 0;
702}
703
704static const struct dev_pm_ops bu21013_dev_pm_ops = {
705 .suspend = bu21013_suspend,
706 .resume = bu21013_resume,
707};
708#endif
709
710static const struct i2c_device_id bu21013_id[] = {
711 { DRIVER_TP, 0 },
712 { }
713};
714MODULE_DEVICE_TABLE(i2c, bu21013_id);
715
716static struct i2c_driver bu21013_driver = {
717 .driver = {
718 .name = DRIVER_TP,
719 .owner = THIS_MODULE,
720#ifdef CONFIG_PM
721 .pm = &bu21013_dev_pm_ops,
722#endif
723 },
724 .probe = bu21013_probe,
725 .remove = bu21013_remove,
726 .id_table = bu21013_id,
727};
728
729module_i2c_driver(bu21013_driver);
730
731MODULE_LICENSE("GPL v2");
732MODULE_AUTHOR("Naveen Kumar G <naveen.gaddipati@stericsson.com>");
733MODULE_DESCRIPTION("bu21013 touch screen controller driver");
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) ST-Ericsson SA 2010
4 * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson
5 */
6
7#include <linux/bitops.h>
8#include <linux/delay.h>
9#include <linux/gpio/consumer.h>
10#include <linux/i2c.h>
11#include <linux/input.h>
12#include <linux/input/mt.h>
13#include <linux/input/touchscreen.h>
14#include <linux/interrupt.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/property.h>
18#include <linux/regulator/consumer.h>
19#include <linux/slab.h>
20#include <linux/types.h>
21
22#define MAX_FINGERS 2
23#define RESET_DELAY 30
24#define PENUP_TIMEOUT (10)
25#define DELTA_MIN 16
26#define MASK_BITS 0x03
27#define SHIFT_8 8
28#define SHIFT_2 2
29#define LENGTH_OF_BUFFER 11
30#define I2C_RETRY_COUNT 5
31
32#define BU21013_SENSORS_BTN_0_7_REG 0x70
33#define BU21013_SENSORS_BTN_8_15_REG 0x71
34#define BU21013_SENSORS_BTN_16_23_REG 0x72
35#define BU21013_X1_POS_MSB_REG 0x73
36#define BU21013_X1_POS_LSB_REG 0x74
37#define BU21013_Y1_POS_MSB_REG 0x75
38#define BU21013_Y1_POS_LSB_REG 0x76
39#define BU21013_X2_POS_MSB_REG 0x77
40#define BU21013_X2_POS_LSB_REG 0x78
41#define BU21013_Y2_POS_MSB_REG 0x79
42#define BU21013_Y2_POS_LSB_REG 0x7A
43#define BU21013_INT_CLR_REG 0xE8
44#define BU21013_INT_MODE_REG 0xE9
45#define BU21013_GAIN_REG 0xEA
46#define BU21013_OFFSET_MODE_REG 0xEB
47#define BU21013_XY_EDGE_REG 0xEC
48#define BU21013_RESET_REG 0xED
49#define BU21013_CALIB_REG 0xEE
50#define BU21013_DONE_REG 0xEF
51#define BU21013_SENSOR_0_7_REG 0xF0
52#define BU21013_SENSOR_8_15_REG 0xF1
53#define BU21013_SENSOR_16_23_REG 0xF2
54#define BU21013_POS_MODE1_REG 0xF3
55#define BU21013_POS_MODE2_REG 0xF4
56#define BU21013_CLK_MODE_REG 0xF5
57#define BU21013_IDLE_REG 0xFA
58#define BU21013_FILTER_REG 0xFB
59#define BU21013_TH_ON_REG 0xFC
60#define BU21013_TH_OFF_REG 0xFD
61
62
63#define BU21013_RESET_ENABLE 0x01
64
65#define BU21013_SENSORS_EN_0_7 0x3F
66#define BU21013_SENSORS_EN_8_15 0xFC
67#define BU21013_SENSORS_EN_16_23 0x1F
68
69#define BU21013_POS_MODE1_0 0x02
70#define BU21013_POS_MODE1_1 0x04
71#define BU21013_POS_MODE1_2 0x08
72
73#define BU21013_POS_MODE2_ZERO 0x01
74#define BU21013_POS_MODE2_AVG1 0x02
75#define BU21013_POS_MODE2_AVG2 0x04
76#define BU21013_POS_MODE2_EN_XY 0x08
77#define BU21013_POS_MODE2_EN_RAW 0x10
78#define BU21013_POS_MODE2_MULTI 0x80
79
80#define BU21013_CLK_MODE_DIV 0x01
81#define BU21013_CLK_MODE_EXT 0x02
82#define BU21013_CLK_MODE_CALIB 0x80
83
84#define BU21013_IDLET_0 0x01
85#define BU21013_IDLET_1 0x02
86#define BU21013_IDLET_2 0x04
87#define BU21013_IDLET_3 0x08
88#define BU21013_IDLE_INTERMIT_EN 0x10
89
90#define BU21013_DELTA_0_6 0x7F
91#define BU21013_FILTER_EN 0x80
92
93#define BU21013_INT_MODE_LEVEL 0x00
94#define BU21013_INT_MODE_EDGE 0x01
95
96#define BU21013_GAIN_0 0x01
97#define BU21013_GAIN_1 0x02
98#define BU21013_GAIN_2 0x04
99
100#define BU21013_OFFSET_MODE_DEFAULT 0x00
101#define BU21013_OFFSET_MODE_MOVE 0x01
102#define BU21013_OFFSET_MODE_DISABLE 0x02
103
104#define BU21013_TH_ON_0 0x01
105#define BU21013_TH_ON_1 0x02
106#define BU21013_TH_ON_2 0x04
107#define BU21013_TH_ON_3 0x08
108#define BU21013_TH_ON_4 0x10
109#define BU21013_TH_ON_5 0x20
110#define BU21013_TH_ON_6 0x40
111#define BU21013_TH_ON_7 0x80
112#define BU21013_TH_ON_MAX 0xFF
113
114#define BU21013_TH_OFF_0 0x01
115#define BU21013_TH_OFF_1 0x02
116#define BU21013_TH_OFF_2 0x04
117#define BU21013_TH_OFF_3 0x08
118#define BU21013_TH_OFF_4 0x10
119#define BU21013_TH_OFF_5 0x20
120#define BU21013_TH_OFF_6 0x40
121#define BU21013_TH_OFF_7 0x80
122#define BU21013_TH_OFF_MAX 0xFF
123
124#define BU21013_X_EDGE_0 0x01
125#define BU21013_X_EDGE_1 0x02
126#define BU21013_X_EDGE_2 0x04
127#define BU21013_X_EDGE_3 0x08
128#define BU21013_Y_EDGE_0 0x10
129#define BU21013_Y_EDGE_1 0x20
130#define BU21013_Y_EDGE_2 0x40
131#define BU21013_Y_EDGE_3 0x80
132
133#define BU21013_DONE 0x01
134#define BU21013_NUMBER_OF_X_SENSORS (6)
135#define BU21013_NUMBER_OF_Y_SENSORS (11)
136
137#define DRIVER_TP "bu21013_tp"
138
139/**
140 * struct bu21013_ts - touch panel data structure
141 * @client: pointer to the i2c client
142 * @in_dev: pointer to the input device structure
143 * @props: the device coordinate transformation properties
144 * @regulator: pointer to the Regulator used for touch screen
145 * @cs_gpiod: chip select GPIO line
146 * @int_gpiod: touch interrupt GPIO line
147 * @touch_x_max: maximum X coordinate reported by the device
148 * @touch_y_max: maximum Y coordinate reported by the device
149 * @x_flip: indicates that the driver should invert X coordinate before
150 * reporting
151 * @y_flip: indicates that the driver should invert Y coordinate before
152 * reporting
153 * @touch_stopped: touch stop flag
154 *
155 * Touch panel device data structure
156 */
157struct bu21013_ts {
158 struct i2c_client *client;
159 struct input_dev *in_dev;
160 struct touchscreen_properties props;
161 struct regulator *regulator;
162 struct gpio_desc *cs_gpiod;
163 struct gpio_desc *int_gpiod;
164 u32 touch_x_max;
165 u32 touch_y_max;
166 bool x_flip;
167 bool y_flip;
168 bool touch_stopped;
169};
170
171static int bu21013_read_block_data(struct bu21013_ts *ts, u8 *buf)
172{
173 int ret, i;
174
175 for (i = 0; i < I2C_RETRY_COUNT; i++) {
176 ret = i2c_smbus_read_i2c_block_data(ts->client,
177 BU21013_SENSORS_BTN_0_7_REG,
178 LENGTH_OF_BUFFER, buf);
179 if (ret == LENGTH_OF_BUFFER)
180 return 0;
181 }
182
183 return -EINVAL;
184}
185
186static int bu21013_do_touch_report(struct bu21013_ts *ts)
187{
188 struct input_dev *input = ts->in_dev;
189 struct input_mt_pos pos[MAX_FINGERS];
190 int slots[MAX_FINGERS];
191 u8 buf[LENGTH_OF_BUFFER];
192 bool has_x_sensors, has_y_sensors;
193 int finger_down_count = 0;
194 int i;
195
196 if (bu21013_read_block_data(ts, buf) < 0)
197 return -EINVAL;
198
199 has_x_sensors = hweight32(buf[0] & BU21013_SENSORS_EN_0_7);
200 has_y_sensors = hweight32(((buf[1] & BU21013_SENSORS_EN_8_15) |
201 ((buf[2] & BU21013_SENSORS_EN_16_23) << SHIFT_8)) >> SHIFT_2);
202 if (!has_x_sensors || !has_y_sensors)
203 return 0;
204
205 for (i = 0; i < MAX_FINGERS; i++) {
206 const u8 *data = &buf[4 * i + 3];
207 unsigned int x, y;
208
209 x = data[0] << SHIFT_2 | (data[1] & MASK_BITS);
210 y = data[2] << SHIFT_2 | (data[3] & MASK_BITS);
211 if (x != 0 && y != 0)
212 touchscreen_set_mt_pos(&pos[finger_down_count++],
213 &ts->props, x, y);
214 }
215
216 if (finger_down_count == 2 &&
217 (abs(pos[0].x - pos[1].x) < DELTA_MIN ||
218 abs(pos[0].y - pos[1].y) < DELTA_MIN)) {
219 return 0;
220 }
221
222 input_mt_assign_slots(input, slots, pos, finger_down_count, DELTA_MIN);
223 for (i = 0; i < finger_down_count; i++) {
224 input_mt_slot(input, slots[i]);
225 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
226 input_report_abs(input, ABS_MT_POSITION_X, pos[i].x);
227 input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y);
228 }
229
230 input_mt_sync_frame(input);
231 input_sync(input);
232
233 return 0;
234}
235
236static irqreturn_t bu21013_gpio_irq(int irq, void *device_data)
237{
238 struct bu21013_ts *ts = device_data;
239 int keep_polling;
240 int error;
241
242 do {
243 error = bu21013_do_touch_report(ts);
244 if (error) {
245 dev_err(&ts->client->dev, "%s failed\n", __func__);
246 break;
247 }
248
249 if (unlikely(ts->touch_stopped))
250 break;
251
252 keep_polling = ts->int_gpiod ?
253 gpiod_get_value(ts->int_gpiod) : false;
254 if (keep_polling)
255 usleep_range(2000, 2500);
256 } while (keep_polling);
257
258 return IRQ_HANDLED;
259}
260
261static int bu21013_init_chip(struct bu21013_ts *ts)
262{
263 struct i2c_client *client = ts->client;
264 int error;
265
266 error = i2c_smbus_write_byte_data(client, BU21013_RESET_REG,
267 BU21013_RESET_ENABLE);
268 if (error) {
269 dev_err(&client->dev, "BU21013_RESET reg write failed\n");
270 return error;
271 }
272 msleep(RESET_DELAY);
273
274 error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_0_7_REG,
275 BU21013_SENSORS_EN_0_7);
276 if (error) {
277 dev_err(&client->dev, "BU21013_SENSOR_0_7 reg write failed\n");
278 return error;
279 }
280
281 error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_8_15_REG,
282 BU21013_SENSORS_EN_8_15);
283 if (error) {
284 dev_err(&client->dev, "BU21013_SENSOR_8_15 reg write failed\n");
285 return error;
286 }
287
288 error = i2c_smbus_write_byte_data(client, BU21013_SENSOR_16_23_REG,
289 BU21013_SENSORS_EN_16_23);
290 if (error) {
291 dev_err(&client->dev, "BU21013_SENSOR_16_23 reg write failed\n");
292 return error;
293 }
294
295 error = i2c_smbus_write_byte_data(client, BU21013_POS_MODE1_REG,
296 BU21013_POS_MODE1_0 |
297 BU21013_POS_MODE1_1);
298 if (error) {
299 dev_err(&client->dev, "BU21013_POS_MODE1 reg write failed\n");
300 return error;
301 }
302
303 error = i2c_smbus_write_byte_data(client, BU21013_POS_MODE2_REG,
304 BU21013_POS_MODE2_ZERO |
305 BU21013_POS_MODE2_AVG1 |
306 BU21013_POS_MODE2_AVG2 |
307 BU21013_POS_MODE2_EN_RAW |
308 BU21013_POS_MODE2_MULTI);
309 if (error) {
310 dev_err(&client->dev, "BU21013_POS_MODE2 reg write failed\n");
311 return error;
312 }
313
314 error = i2c_smbus_write_byte_data(client, BU21013_CLK_MODE_REG,
315 BU21013_CLK_MODE_DIV |
316 BU21013_CLK_MODE_CALIB);
317 if (error) {
318 dev_err(&client->dev, "BU21013_CLK_MODE reg write failed\n");
319 return error;
320 }
321
322 error = i2c_smbus_write_byte_data(client, BU21013_IDLE_REG,
323 BU21013_IDLET_0 |
324 BU21013_IDLE_INTERMIT_EN);
325 if (error) {
326 dev_err(&client->dev, "BU21013_IDLE reg write failed\n");
327 return error;
328 }
329
330 error = i2c_smbus_write_byte_data(client, BU21013_INT_MODE_REG,
331 BU21013_INT_MODE_LEVEL);
332 if (error) {
333 dev_err(&client->dev, "BU21013_INT_MODE reg write failed\n");
334 return error;
335 }
336
337 error = i2c_smbus_write_byte_data(client, BU21013_FILTER_REG,
338 BU21013_DELTA_0_6 |
339 BU21013_FILTER_EN);
340 if (error) {
341 dev_err(&client->dev, "BU21013_FILTER reg write failed\n");
342 return error;
343 }
344
345 error = i2c_smbus_write_byte_data(client, BU21013_TH_ON_REG,
346 BU21013_TH_ON_5);
347 if (error) {
348 dev_err(&client->dev, "BU21013_TH_ON reg write failed\n");
349 return error;
350 }
351
352 error = i2c_smbus_write_byte_data(client, BU21013_TH_OFF_REG,
353 BU21013_TH_OFF_4 | BU21013_TH_OFF_3);
354 if (error) {
355 dev_err(&client->dev, "BU21013_TH_OFF reg write failed\n");
356 return error;
357 }
358
359 error = i2c_smbus_write_byte_data(client, BU21013_GAIN_REG,
360 BU21013_GAIN_0 | BU21013_GAIN_1);
361 if (error) {
362 dev_err(&client->dev, "BU21013_GAIN reg write failed\n");
363 return error;
364 }
365
366 error = i2c_smbus_write_byte_data(client, BU21013_OFFSET_MODE_REG,
367 BU21013_OFFSET_MODE_DEFAULT);
368 if (error) {
369 dev_err(&client->dev, "BU21013_OFFSET_MODE reg write failed\n");
370 return error;
371 }
372
373 error = i2c_smbus_write_byte_data(client, BU21013_XY_EDGE_REG,
374 BU21013_X_EDGE_0 |
375 BU21013_X_EDGE_2 |
376 BU21013_Y_EDGE_1 |
377 BU21013_Y_EDGE_3);
378 if (error) {
379 dev_err(&client->dev, "BU21013_XY_EDGE reg write failed\n");
380 return error;
381 }
382
383 error = i2c_smbus_write_byte_data(client, BU21013_DONE_REG,
384 BU21013_DONE);
385 if (error) {
386 dev_err(&client->dev, "BU21013_REG_DONE reg write failed\n");
387 return error;
388 }
389
390 return 0;
391}
392
393static void bu21013_power_off(void *_ts)
394{
395 struct bu21013_ts *ts = _ts;
396
397 regulator_disable(ts->regulator);
398}
399
400static void bu21013_disable_chip(void *_ts)
401{
402 struct bu21013_ts *ts = _ts;
403
404 gpiod_set_value(ts->cs_gpiod, 0);
405}
406
407static int bu21013_probe(struct i2c_client *client)
408{
409 struct bu21013_ts *ts;
410 struct input_dev *in_dev;
411 struct input_absinfo *info;
412 u32 max_x = 0, max_y = 0;
413 struct device *dev = &client->dev;
414 int error;
415
416 if (!i2c_check_functionality(client->adapter,
417 I2C_FUNC_SMBUS_BYTE_DATA)) {
418 dev_err(dev, "i2c smbus byte data not supported\n");
419 return -EIO;
420 }
421
422 if (!client->irq) {
423 dev_err(dev, "No IRQ set up\n");
424 return -EINVAL;
425 }
426
427 ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
428 if (!ts)
429 return -ENOMEM;
430
431 ts->client = client;
432
433 ts->x_flip = device_property_read_bool(dev, "rohm,flip-x");
434 ts->y_flip = device_property_read_bool(dev, "rohm,flip-y");
435
436 in_dev = devm_input_allocate_device(dev);
437 if (!in_dev) {
438 dev_err(dev, "device memory alloc failed\n");
439 return -ENOMEM;
440 }
441 ts->in_dev = in_dev;
442 input_set_drvdata(in_dev, ts);
443
444 /* register the device to input subsystem */
445 in_dev->name = DRIVER_TP;
446 in_dev->id.bustype = BUS_I2C;
447
448 device_property_read_u32(dev, "rohm,touch-max-x", &max_x);
449 device_property_read_u32(dev, "rohm,touch-max-y", &max_y);
450
451 input_set_abs_params(in_dev, ABS_MT_POSITION_X, 0, max_x, 0, 0);
452 input_set_abs_params(in_dev, ABS_MT_POSITION_Y, 0, max_y, 0, 0);
453
454 touchscreen_parse_properties(in_dev, true, &ts->props);
455
456 /* Adjust for the legacy "flip" properties, if present */
457 if (!ts->props.invert_x &&
458 device_property_read_bool(dev, "rohm,flip-x")) {
459 info = &in_dev->absinfo[ABS_MT_POSITION_X];
460 info->maximum -= info->minimum;
461 info->minimum = 0;
462 }
463
464 if (!ts->props.invert_y &&
465 device_property_read_bool(dev, "rohm,flip-y")) {
466 info = &in_dev->absinfo[ABS_MT_POSITION_Y];
467 info->maximum -= info->minimum;
468 info->minimum = 0;
469 }
470
471 error = input_mt_init_slots(in_dev, MAX_FINGERS,
472 INPUT_MT_DIRECT | INPUT_MT_TRACK |
473 INPUT_MT_DROP_UNUSED);
474 if (error) {
475 dev_err(dev, "failed to initialize MT slots");
476 return error;
477 }
478
479 ts->regulator = devm_regulator_get(dev, "avdd");
480 if (IS_ERR(ts->regulator)) {
481 dev_err(dev, "regulator_get failed\n");
482 return PTR_ERR(ts->regulator);
483 }
484
485 error = regulator_enable(ts->regulator);
486 if (error) {
487 dev_err(dev, "regulator enable failed\n");
488 return error;
489 }
490
491 error = devm_add_action_or_reset(dev, bu21013_power_off, ts);
492 if (error) {
493 dev_err(dev, "failed to install power off handler\n");
494 return error;
495 }
496
497 /* Named "CS" on the chip, DT binding is "reset" */
498 ts->cs_gpiod = devm_gpiod_get(dev, "reset", GPIOD_OUT_HIGH);
499 if (IS_ERR(ts->cs_gpiod))
500 return dev_err_probe(dev, PTR_ERR(ts->cs_gpiod), "failed to get CS GPIO\n");
501
502 gpiod_set_consumer_name(ts->cs_gpiod, "BU21013 CS");
503
504 error = devm_add_action_or_reset(dev, bu21013_disable_chip, ts);
505 if (error) {
506 dev_err(dev, "failed to install chip disable handler\n");
507 return error;
508 }
509
510 /* Named "INT" on the chip, DT binding is "touch" */
511 ts->int_gpiod = devm_gpiod_get_optional(dev, "touch", GPIOD_IN);
512 error = PTR_ERR_OR_ZERO(ts->int_gpiod);
513 if (error)
514 return dev_err_probe(dev, error, "failed to get INT GPIO\n");
515
516 if (ts->int_gpiod)
517 gpiod_set_consumer_name(ts->int_gpiod, "BU21013 INT");
518
519 /* configure the touch panel controller */
520 error = bu21013_init_chip(ts);
521 if (error) {
522 dev_err(dev, "error in bu21013 config\n");
523 return error;
524 }
525
526 error = devm_request_threaded_irq(dev, client->irq, NULL, bu21013_gpio_irq,
527 IRQF_ONESHOT, DRIVER_TP, ts);
528 if (error) {
529 dev_err(dev, "request irq %d failed\n", client->irq);
530 return error;
531 }
532
533 error = input_register_device(in_dev);
534 if (error) {
535 dev_err(dev, "failed to register input device\n");
536 return error;
537 }
538
539 i2c_set_clientdata(client, ts);
540
541 return 0;
542}
543
544static void bu21013_remove(struct i2c_client *client)
545{
546 struct bu21013_ts *ts = i2c_get_clientdata(client);
547
548 /* Make sure IRQ will exit quickly even if there is contact */
549 ts->touch_stopped = true;
550 /* The resources will be freed by devm */
551}
552
553static int bu21013_suspend(struct device *dev)
554{
555 struct i2c_client *client = to_i2c_client(dev);
556 struct bu21013_ts *ts = i2c_get_clientdata(client);
557
558 ts->touch_stopped = true;
559 mb();
560 disable_irq(client->irq);
561
562 if (!device_may_wakeup(&client->dev))
563 regulator_disable(ts->regulator);
564
565 return 0;
566}
567
568static int bu21013_resume(struct device *dev)
569{
570 struct i2c_client *client = to_i2c_client(dev);
571 struct bu21013_ts *ts = i2c_get_clientdata(client);
572 int error;
573
574 if (!device_may_wakeup(&client->dev)) {
575 error = regulator_enable(ts->regulator);
576 if (error) {
577 dev_err(&client->dev,
578 "failed to re-enable regulator when resuming\n");
579 return error;
580 }
581
582 error = bu21013_init_chip(ts);
583 if (error) {
584 dev_err(&client->dev,
585 "failed to reinitialize chip when resuming\n");
586 return error;
587 }
588 }
589
590 ts->touch_stopped = false;
591 mb();
592 enable_irq(client->irq);
593
594 return 0;
595}
596
597static DEFINE_SIMPLE_DEV_PM_OPS(bu21013_dev_pm_ops, bu21013_suspend, bu21013_resume);
598
599static const struct i2c_device_id bu21013_id[] = {
600 { DRIVER_TP },
601 { }
602};
603MODULE_DEVICE_TABLE(i2c, bu21013_id);
604
605static struct i2c_driver bu21013_driver = {
606 .driver = {
607 .name = DRIVER_TP,
608 .pm = pm_sleep_ptr(&bu21013_dev_pm_ops),
609 },
610 .probe = bu21013_probe,
611 .remove = bu21013_remove,
612 .id_table = bu21013_id,
613};
614
615module_i2c_driver(bu21013_driver);
616
617MODULE_LICENSE("GPL v2");
618MODULE_AUTHOR("Naveen Kumar G <naveen.gaddipati@stericsson.com>");
619MODULE_DESCRIPTION("bu21013 touch screen controller driver");