1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2012-2013 MundoReader S.L.
4 * Author: Heiko Stuebner <heiko@sntech.de>
5 *
6 * based in parts on Nook zforce driver
7 *
8 * Copyright (C) 2010 Barnes & Noble, Inc.
9 * Author: Pieter Truter<ptruter@intrinsyc.com>
10 */
11
12#include <linux/module.h>
13#include <linux/hrtimer.h>
14#include <linux/slab.h>
15#include <linux/input.h>
16#include <linux/interrupt.h>
17#include <linux/i2c.h>
18#include <linux/delay.h>
19#include <linux/gpio/consumer.h>
20#include <linux/device.h>
21#include <linux/sysfs.h>
22#include <linux/input/mt.h>
23#include <linux/input/touchscreen.h>
24#include <linux/platform_data/zforce_ts.h>
25#include <linux/regulator/consumer.h>
26#include <linux/of.h>
27
28#define WAIT_TIMEOUT msecs_to_jiffies(1000)
29
30#define FRAME_START 0xee
31#define FRAME_MAXSIZE 257
32
33/* Offsets of the different parts of the payload the controller sends */
34#define PAYLOAD_HEADER 0
35#define PAYLOAD_LENGTH 1
36#define PAYLOAD_BODY 2
37
38/* Response offsets */
39#define RESPONSE_ID 0
40#define RESPONSE_DATA 1
41
42/* Commands */
43#define COMMAND_DEACTIVATE 0x00
44#define COMMAND_INITIALIZE 0x01
45#define COMMAND_RESOLUTION 0x02
46#define COMMAND_SETCONFIG 0x03
47#define COMMAND_DATAREQUEST 0x04
48#define COMMAND_SCANFREQ 0x08
49#define COMMAND_STATUS 0X1e
50
51/*
52 * Responses the controller sends as a result of
53 * command requests
54 */
55#define RESPONSE_DEACTIVATE 0x00
56#define RESPONSE_INITIALIZE 0x01
57#define RESPONSE_RESOLUTION 0x02
58#define RESPONSE_SETCONFIG 0x03
59#define RESPONSE_SCANFREQ 0x08
60#define RESPONSE_STATUS 0X1e
61
62/*
63 * Notifications are sent by the touch controller without
64 * being requested by the driver and include for example
65 * touch indications
66 */
67#define NOTIFICATION_TOUCH 0x04
68#define NOTIFICATION_BOOTCOMPLETE 0x07
69#define NOTIFICATION_OVERRUN 0x25
70#define NOTIFICATION_PROXIMITY 0x26
71#define NOTIFICATION_INVALID_COMMAND 0xfe
72
73#define ZFORCE_REPORT_POINTS 2
74#define ZFORCE_MAX_AREA 0xff
75
76#define STATE_DOWN 0
77#define STATE_MOVE 1
78#define STATE_UP 2
79
80#define SETCONFIG_DUALTOUCH (1 << 0)
81
82struct zforce_point {
83 int coord_x;
84 int coord_y;
85 int state;
86 int id;
87 int area_major;
88 int area_minor;
89 int orientation;
90 int pressure;
91 int prblty;
92};
93
94/*
95 * @client the i2c_client
96 * @input the input device
97 * @suspending in the process of going to suspend (don't emit wakeup
98 * events for commands executed to suspend the device)
99 * @suspended device suspended
100 * @access_mutex serialize i2c-access, to keep multipart reads together
101 * @command_done completion to wait for the command result
102 * @command_mutex serialize commands sent to the ic
103 * @command_waiting the id of the command that is currently waiting
104 * for a result
105 * @command_result returned result of the command
106 */
107struct zforce_ts {
108 struct i2c_client *client;
109 struct input_dev *input;
110 struct touchscreen_properties prop;
111 const struct zforce_ts_platdata *pdata;
112 char phys[32];
113
114 struct regulator *reg_vdd;
115
116 struct gpio_desc *gpio_int;
117 struct gpio_desc *gpio_rst;
118
119 bool suspending;
120 bool suspended;
121 bool boot_complete;
122
123 /* Firmware version information */
124 u16 version_major;
125 u16 version_minor;
126 u16 version_build;
127 u16 version_rev;
128
129 struct mutex access_mutex;
130
131 struct completion command_done;
132 struct mutex command_mutex;
133 int command_waiting;
134 int command_result;
135};
136
137static int zforce_command(struct zforce_ts *ts, u8 cmd)
138{
139 struct i2c_client *client = ts->client;
140 char buf[3];
141 int ret;
142
143 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
144
145 buf[0] = FRAME_START;
146 buf[1] = 1; /* data size, command only */
147 buf[2] = cmd;
148
149 mutex_lock(&ts->access_mutex);
150 ret = i2c_master_send(client, buf: &buf[0], ARRAY_SIZE(buf));
151 mutex_unlock(lock: &ts->access_mutex);
152 if (ret < 0) {
153 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
154 return ret;
155 }
156
157 return 0;
158}
159
160static void zforce_reset_assert(struct zforce_ts *ts)
161{
162 gpiod_set_value_cansleep(desc: ts->gpio_rst, value: 1);
163}
164
165static void zforce_reset_deassert(struct zforce_ts *ts)
166{
167 gpiod_set_value_cansleep(desc: ts->gpio_rst, value: 0);
168}
169
170static int zforce_send_wait(struct zforce_ts *ts, const char *buf, int len)
171{
172 struct i2c_client *client = ts->client;
173 int ret;
174
175 ret = mutex_trylock(lock: &ts->command_mutex);
176 if (!ret) {
177 dev_err(&client->dev, "already waiting for a command\n");
178 return -EBUSY;
179 }
180
181 dev_dbg(&client->dev, "sending %d bytes for command 0x%x\n",
182 buf[1], buf[2]);
183
184 ts->command_waiting = buf[2];
185
186 mutex_lock(&ts->access_mutex);
187 ret = i2c_master_send(client, buf, count: len);
188 mutex_unlock(lock: &ts->access_mutex);
189 if (ret < 0) {
190 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
191 goto unlock;
192 }
193
194 dev_dbg(&client->dev, "waiting for result for command 0x%x\n", buf[2]);
195
196 if (wait_for_completion_timeout(x: &ts->command_done, WAIT_TIMEOUT) == 0) {
197 ret = -ETIME;
198 goto unlock;
199 }
200
201 ret = ts->command_result;
202
203unlock:
204 mutex_unlock(lock: &ts->command_mutex);
205 return ret;
206}
207
208static int zforce_command_wait(struct zforce_ts *ts, u8 cmd)
209{
210 struct i2c_client *client = ts->client;
211 char buf[3];
212 int ret;
213
214 dev_dbg(&client->dev, "%s: 0x%x\n", __func__, cmd);
215
216 buf[0] = FRAME_START;
217 buf[1] = 1; /* data size, command only */
218 buf[2] = cmd;
219
220 ret = zforce_send_wait(ts, buf: &buf[0], ARRAY_SIZE(buf));
221 if (ret < 0) {
222 dev_err(&client->dev, "i2c send data request error: %d\n", ret);
223 return ret;
224 }
225
226 return 0;
227}
228
229static int zforce_resolution(struct zforce_ts *ts, u16 x, u16 y)
230{
231 struct i2c_client *client = ts->client;
232 char buf[7] = { FRAME_START, 5, COMMAND_RESOLUTION,
233 (x & 0xff), ((x >> 8) & 0xff),
234 (y & 0xff), ((y >> 8) & 0xff) };
235
236 dev_dbg(&client->dev, "set resolution to (%d,%d)\n", x, y);
237
238 return zforce_send_wait(ts, buf: &buf[0], ARRAY_SIZE(buf));
239}
240
241static int zforce_scan_frequency(struct zforce_ts *ts, u16 idle, u16 finger,
242 u16 stylus)
243{
244 struct i2c_client *client = ts->client;
245 char buf[9] = { FRAME_START, 7, COMMAND_SCANFREQ,
246 (idle & 0xff), ((idle >> 8) & 0xff),
247 (finger & 0xff), ((finger >> 8) & 0xff),
248 (stylus & 0xff), ((stylus >> 8) & 0xff) };
249
250 dev_dbg(&client->dev,
251 "set scan frequency to (idle: %d, finger: %d, stylus: %d)\n",
252 idle, finger, stylus);
253
254 return zforce_send_wait(ts, buf: &buf[0], ARRAY_SIZE(buf));
255}
256
257static int zforce_setconfig(struct zforce_ts *ts, char b1)
258{
259 struct i2c_client *client = ts->client;
260 char buf[7] = { FRAME_START, 5, COMMAND_SETCONFIG,
261 b1, 0, 0, 0 };
262
263 dev_dbg(&client->dev, "set config to (%d)\n", b1);
264
265 return zforce_send_wait(ts, buf: &buf[0], ARRAY_SIZE(buf));
266}
267
268static int zforce_start(struct zforce_ts *ts)
269{
270 struct i2c_client *client = ts->client;
271 int ret;
272
273 dev_dbg(&client->dev, "starting device\n");
274
275 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
276 if (ret) {
277 dev_err(&client->dev, "Unable to initialize, %d\n", ret);
278 return ret;
279 }
280
281 ret = zforce_resolution(ts, x: ts->prop.max_x, y: ts->prop.max_y);
282 if (ret) {
283 dev_err(&client->dev, "Unable to set resolution, %d\n", ret);
284 goto error;
285 }
286
287 ret = zforce_scan_frequency(ts, idle: 10, finger: 50, stylus: 50);
288 if (ret) {
289 dev_err(&client->dev, "Unable to set scan frequency, %d\n",
290 ret);
291 goto error;
292 }
293
294 ret = zforce_setconfig(ts, SETCONFIG_DUALTOUCH);
295 if (ret) {
296 dev_err(&client->dev, "Unable to set config\n");
297 goto error;
298 }
299
300 /* start sending touch events */
301 ret = zforce_command(ts, COMMAND_DATAREQUEST);
302 if (ret) {
303 dev_err(&client->dev, "Unable to request data\n");
304 goto error;
305 }
306
307 /*
308 * Per NN, initial cal. take max. of 200msec.
309 * Allow time to complete this calibration
310 */
311 msleep(msecs: 200);
312
313 return 0;
314
315error:
316 zforce_command_wait(ts, COMMAND_DEACTIVATE);
317 return ret;
318}
319
320static int zforce_stop(struct zforce_ts *ts)
321{
322 struct i2c_client *client = ts->client;
323 int ret;
324
325 dev_dbg(&client->dev, "stopping device\n");
326
327 /* Deactivates touch sensing and puts the device into sleep. */
328 ret = zforce_command_wait(ts, COMMAND_DEACTIVATE);
329 if (ret != 0) {
330 dev_err(&client->dev, "could not deactivate device, %d\n",
331 ret);
332 return ret;
333 }
334
335 return 0;
336}
337
338static int zforce_touch_event(struct zforce_ts *ts, u8 *payload)
339{
340 struct i2c_client *client = ts->client;
341 struct zforce_point point;
342 int count, i, num = 0;
343
344 count = payload[0];
345 if (count > ZFORCE_REPORT_POINTS) {
346 dev_warn(&client->dev,
347 "too many coordinates %d, expected max %d\n",
348 count, ZFORCE_REPORT_POINTS);
349 count = ZFORCE_REPORT_POINTS;
350 }
351
352 for (i = 0; i < count; i++) {
353 point.coord_x =
354 payload[9 * i + 2] << 8 | payload[9 * i + 1];
355 point.coord_y =
356 payload[9 * i + 4] << 8 | payload[9 * i + 3];
357
358 if (point.coord_x > ts->prop.max_x ||
359 point.coord_y > ts->prop.max_y) {
360 dev_warn(&client->dev, "coordinates (%d,%d) invalid\n",
361 point.coord_x, point.coord_y);
362 point.coord_x = point.coord_y = 0;
363 }
364
365 point.state = payload[9 * i + 5] & 0x0f;
366 point.id = (payload[9 * i + 5] & 0xf0) >> 4;
367
368 /* determine touch major, minor and orientation */
369 point.area_major = max(payload[9 * i + 6],
370 payload[9 * i + 7]);
371 point.area_minor = min(payload[9 * i + 6],
372 payload[9 * i + 7]);
373 point.orientation = payload[9 * i + 6] > payload[9 * i + 7];
374
375 point.pressure = payload[9 * i + 8];
376 point.prblty = payload[9 * i + 9];
377
378 dev_dbg(&client->dev,
379 "point %d/%d: state %d, id %d, pressure %d, prblty %d, x %d, y %d, amajor %d, aminor %d, ori %d\n",
380 i, count, point.state, point.id,
381 point.pressure, point.prblty,
382 point.coord_x, point.coord_y,
383 point.area_major, point.area_minor,
384 point.orientation);
385
386 /* the zforce id starts with "1", so needs to be decreased */
387 input_mt_slot(dev: ts->input, slot: point.id - 1);
388
389 input_mt_report_slot_state(dev: ts->input, MT_TOOL_FINGER,
390 active: point.state != STATE_UP);
391
392 if (point.state != STATE_UP) {
393 touchscreen_report_pos(input: ts->input, prop: &ts->prop,
394 x: point.coord_x, y: point.coord_y,
395 multitouch: true);
396 input_report_abs(dev: ts->input, ABS_MT_TOUCH_MAJOR,
397 value: point.area_major);
398 input_report_abs(dev: ts->input, ABS_MT_TOUCH_MINOR,
399 value: point.area_minor);
400 input_report_abs(dev: ts->input, ABS_MT_ORIENTATION,
401 value: point.orientation);
402 num++;
403 }
404 }
405
406 input_mt_sync_frame(dev: ts->input);
407
408 input_mt_report_finger_count(dev: ts->input, count: num);
409
410 input_sync(dev: ts->input);
411
412 return 0;
413}
414
415static int zforce_read_packet(struct zforce_ts *ts, u8 *buf)
416{
417 struct i2c_client *client = ts->client;
418 int ret;
419
420 mutex_lock(&ts->access_mutex);
421
422 /* read 2 byte message header */
423 ret = i2c_master_recv(client, buf, count: 2);
424 if (ret < 0) {
425 dev_err(&client->dev, "error reading header: %d\n", ret);
426 goto unlock;
427 }
428
429 if (buf[PAYLOAD_HEADER] != FRAME_START) {
430 dev_err(&client->dev, "invalid frame start: %d\n", buf[0]);
431 ret = -EIO;
432 goto unlock;
433 }
434
435 if (buf[PAYLOAD_LENGTH] == 0) {
436 dev_err(&client->dev, "invalid payload length: %d\n",
437 buf[PAYLOAD_LENGTH]);
438 ret = -EIO;
439 goto unlock;
440 }
441
442 /* read the message */
443 ret = i2c_master_recv(client, buf: &buf[PAYLOAD_BODY], count: buf[PAYLOAD_LENGTH]);
444 if (ret < 0) {
445 dev_err(&client->dev, "error reading payload: %d\n", ret);
446 goto unlock;
447 }
448
449 dev_dbg(&client->dev, "read %d bytes for response command 0x%x\n",
450 buf[PAYLOAD_LENGTH], buf[PAYLOAD_BODY]);
451
452unlock:
453 mutex_unlock(lock: &ts->access_mutex);
454 return ret;
455}
456
457static void zforce_complete(struct zforce_ts *ts, int cmd, int result)
458{
459 struct i2c_client *client = ts->client;
460
461 if (ts->command_waiting == cmd) {
462 dev_dbg(&client->dev, "completing command 0x%x\n", cmd);
463 ts->command_result = result;
464 complete(&ts->command_done);
465 } else {
466 dev_dbg(&client->dev, "command %d not for us\n", cmd);
467 }
468}
469
470static irqreturn_t zforce_irq(int irq, void *dev_id)
471{
472 struct zforce_ts *ts = dev_id;
473 struct i2c_client *client = ts->client;
474
475 if (ts->suspended && device_may_wakeup(dev: &client->dev))
476 pm_wakeup_event(dev: &client->dev, msec: 500);
477
478 return IRQ_WAKE_THREAD;
479}
480
481static irqreturn_t zforce_irq_thread(int irq, void *dev_id)
482{
483 struct zforce_ts *ts = dev_id;
484 struct i2c_client *client = ts->client;
485 int ret;
486 u8 payload_buffer[FRAME_MAXSIZE];
487 u8 *payload;
488
489 /*
490 * When still suspended, return.
491 * Due to the level-interrupt we will get re-triggered later.
492 */
493 if (ts->suspended) {
494 msleep(msecs: 20);
495 return IRQ_HANDLED;
496 }
497
498 dev_dbg(&client->dev, "handling interrupt\n");
499
500 /* Don't emit wakeup events from commands run by zforce_suspend */
501 if (!ts->suspending && device_may_wakeup(dev: &client->dev))
502 pm_stay_awake(dev: &client->dev);
503
504 /*
505 * Run at least once and exit the loop if
506 * - the optional interrupt GPIO isn't specified
507 * (there is only one packet read per ISR invocation, then)
508 * or
509 * - the GPIO isn't active any more
510 * (packet read until the level GPIO indicates that there is
511 * no IRQ any more)
512 */
513 do {
514 ret = zforce_read_packet(ts, buf: payload_buffer);
515 if (ret < 0) {
516 dev_err(&client->dev,
517 "could not read packet, ret: %d\n", ret);
518 break;
519 }
520
521 payload = &payload_buffer[PAYLOAD_BODY];
522
523 switch (payload[RESPONSE_ID]) {
524 case NOTIFICATION_TOUCH:
525 /*
526 * Always report touch-events received while
527 * suspending, when being a wakeup source
528 */
529 if (ts->suspending && device_may_wakeup(dev: &client->dev))
530 pm_wakeup_event(dev: &client->dev, msec: 500);
531 zforce_touch_event(ts, payload: &payload[RESPONSE_DATA]);
532 break;
533
534 case NOTIFICATION_BOOTCOMPLETE:
535 ts->boot_complete = payload[RESPONSE_DATA];
536 zforce_complete(ts, cmd: payload[RESPONSE_ID], result: 0);
537 break;
538
539 case RESPONSE_INITIALIZE:
540 case RESPONSE_DEACTIVATE:
541 case RESPONSE_SETCONFIG:
542 case RESPONSE_RESOLUTION:
543 case RESPONSE_SCANFREQ:
544 zforce_complete(ts, cmd: payload[RESPONSE_ID],
545 result: payload[RESPONSE_DATA]);
546 break;
547
548 case RESPONSE_STATUS:
549 /*
550 * Version Payload Results
551 * [2:major] [2:minor] [2:build] [2:rev]
552 */
553 ts->version_major = (payload[RESPONSE_DATA + 1] << 8) |
554 payload[RESPONSE_DATA];
555 ts->version_minor = (payload[RESPONSE_DATA + 3] << 8) |
556 payload[RESPONSE_DATA + 2];
557 ts->version_build = (payload[RESPONSE_DATA + 5] << 8) |
558 payload[RESPONSE_DATA + 4];
559 ts->version_rev = (payload[RESPONSE_DATA + 7] << 8) |
560 payload[RESPONSE_DATA + 6];
561 dev_dbg(&ts->client->dev,
562 "Firmware Version %04x:%04x %04x:%04x\n",
563 ts->version_major, ts->version_minor,
564 ts->version_build, ts->version_rev);
565
566 zforce_complete(ts, cmd: payload[RESPONSE_ID], result: 0);
567 break;
568
569 case NOTIFICATION_INVALID_COMMAND:
570 dev_err(&ts->client->dev, "invalid command: 0x%x\n",
571 payload[RESPONSE_DATA]);
572 break;
573
574 default:
575 dev_err(&ts->client->dev,
576 "unrecognized response id: 0x%x\n",
577 payload[RESPONSE_ID]);
578 break;
579 }
580 } while (gpiod_get_value_cansleep(desc: ts->gpio_int));
581
582 if (!ts->suspending && device_may_wakeup(dev: &client->dev))
583 pm_relax(dev: &client->dev);
584
585 dev_dbg(&client->dev, "finished interrupt\n");
586
587 return IRQ_HANDLED;
588}
589
590static int zforce_input_open(struct input_dev *dev)
591{
592 struct zforce_ts *ts = input_get_drvdata(dev);
593
594 return zforce_start(ts);
595}
596
597static void zforce_input_close(struct input_dev *dev)
598{
599 struct zforce_ts *ts = input_get_drvdata(dev);
600 struct i2c_client *client = ts->client;
601 int ret;
602
603 ret = zforce_stop(ts);
604 if (ret)
605 dev_warn(&client->dev, "stopping zforce failed\n");
606
607 return;
608}
609
610static int zforce_suspend(struct device *dev)
611{
612 struct i2c_client *client = to_i2c_client(dev);
613 struct zforce_ts *ts = i2c_get_clientdata(client);
614 struct input_dev *input = ts->input;
615 int ret = 0;
616
617 mutex_lock(&input->mutex);
618 ts->suspending = true;
619
620 /*
621 * When configured as a wakeup source device should always wake
622 * the system, therefore start device if necessary.
623 */
624 if (device_may_wakeup(dev: &client->dev)) {
625 dev_dbg(&client->dev, "suspend while being a wakeup source\n");
626
627 /* Need to start device, if not open, to be a wakeup source. */
628 if (!input_device_enabled(dev: input)) {
629 ret = zforce_start(ts);
630 if (ret)
631 goto unlock;
632 }
633
634 enable_irq_wake(irq: client->irq);
635 } else if (input_device_enabled(dev: input)) {
636 dev_dbg(&client->dev,
637 "suspend without being a wakeup source\n");
638
639 ret = zforce_stop(ts);
640 if (ret)
641 goto unlock;
642
643 disable_irq(irq: client->irq);
644 }
645
646 ts->suspended = true;
647
648unlock:
649 ts->suspending = false;
650 mutex_unlock(lock: &input->mutex);
651
652 return ret;
653}
654
655static int zforce_resume(struct device *dev)
656{
657 struct i2c_client *client = to_i2c_client(dev);
658 struct zforce_ts *ts = i2c_get_clientdata(client);
659 struct input_dev *input = ts->input;
660 int ret = 0;
661
662 mutex_lock(&input->mutex);
663
664 ts->suspended = false;
665
666 if (device_may_wakeup(dev: &client->dev)) {
667 dev_dbg(&client->dev, "resume from being a wakeup source\n");
668
669 disable_irq_wake(irq: client->irq);
670
671 /* need to stop device if it was not open on suspend */
672 if (!input_device_enabled(dev: input)) {
673 ret = zforce_stop(ts);
674 if (ret)
675 goto unlock;
676 }
677 } else if (input_device_enabled(dev: input)) {
678 dev_dbg(&client->dev, "resume without being a wakeup source\n");
679
680 enable_irq(irq: client->irq);
681
682 ret = zforce_start(ts);
683 if (ret < 0)
684 goto unlock;
685 }
686
687unlock:
688 mutex_unlock(lock: &input->mutex);
689
690 return ret;
691}
692
693static DEFINE_SIMPLE_DEV_PM_OPS(zforce_pm_ops, zforce_suspend, zforce_resume);
694
695static void zforce_reset(void *data)
696{
697 struct zforce_ts *ts = data;
698
699 zforce_reset_assert(ts);
700
701 udelay(10);
702
703 if (!IS_ERR(ptr: ts->reg_vdd))
704 regulator_disable(regulator: ts->reg_vdd);
705}
706
707static struct zforce_ts_platdata *zforce_parse_dt(struct device *dev)
708{
709 struct zforce_ts_platdata *pdata;
710 struct device_node *np = dev->of_node;
711
712 if (!np)
713 return ERR_PTR(error: -ENOENT);
714
715 pdata = devm_kzalloc(dev, size: sizeof(*pdata), GFP_KERNEL);
716 if (!pdata) {
717 dev_err(dev, "failed to allocate platform data\n");
718 return ERR_PTR(error: -ENOMEM);
719 }
720
721 of_property_read_u32(np, propname: "x-size", out_value: &pdata->x_max);
722 of_property_read_u32(np, propname: "y-size", out_value: &pdata->y_max);
723
724 return pdata;
725}
726
727static int zforce_probe(struct i2c_client *client)
728{
729 const struct zforce_ts_platdata *pdata = dev_get_platdata(dev: &client->dev);
730 struct zforce_ts *ts;
731 struct input_dev *input_dev;
732 int ret;
733
734 if (!pdata) {
735 pdata = zforce_parse_dt(dev: &client->dev);
736 if (IS_ERR(ptr: pdata))
737 return PTR_ERR(ptr: pdata);
738 }
739
740 ts = devm_kzalloc(dev: &client->dev, size: sizeof(struct zforce_ts), GFP_KERNEL);
741 if (!ts)
742 return -ENOMEM;
743
744 ts->gpio_rst = devm_gpiod_get_optional(dev: &client->dev, con_id: "reset",
745 flags: GPIOD_OUT_HIGH);
746 if (IS_ERR(ptr: ts->gpio_rst)) {
747 ret = PTR_ERR(ptr: ts->gpio_rst);
748 dev_err(&client->dev,
749 "failed to request reset GPIO: %d\n", ret);
750 return ret;
751 }
752
753 if (ts->gpio_rst) {
754 ts->gpio_int = devm_gpiod_get_optional(dev: &client->dev, con_id: "irq",
755 flags: GPIOD_IN);
756 if (IS_ERR(ptr: ts->gpio_int)) {
757 ret = PTR_ERR(ptr: ts->gpio_int);
758 dev_err(&client->dev,
759 "failed to request interrupt GPIO: %d\n", ret);
760 return ret;
761 }
762 } else {
763 /*
764 * Deprecated GPIO handling for compatibility
765 * with legacy binding.
766 */
767
768 /* INT GPIO */
769 ts->gpio_int = devm_gpiod_get_index(dev: &client->dev, NULL, idx: 0,
770 flags: GPIOD_IN);
771 if (IS_ERR(ptr: ts->gpio_int)) {
772 ret = PTR_ERR(ptr: ts->gpio_int);
773 dev_err(&client->dev,
774 "failed to request interrupt GPIO: %d\n", ret);
775 return ret;
776 }
777
778 /* RST GPIO */
779 ts->gpio_rst = devm_gpiod_get_index(dev: &client->dev, NULL, idx: 1,
780 flags: GPIOD_OUT_HIGH);
781 if (IS_ERR(ptr: ts->gpio_rst)) {
782 ret = PTR_ERR(ptr: ts->gpio_rst);
783 dev_err(&client->dev,
784 "failed to request reset GPIO: %d\n", ret);
785 return ret;
786 }
787 }
788
789 ts->reg_vdd = devm_regulator_get_optional(dev: &client->dev, id: "vdd");
790 if (IS_ERR(ptr: ts->reg_vdd)) {
791 ret = PTR_ERR(ptr: ts->reg_vdd);
792 if (ret == -EPROBE_DEFER)
793 return ret;
794 } else {
795 ret = regulator_enable(regulator: ts->reg_vdd);
796 if (ret)
797 return ret;
798
799 /*
800 * according to datasheet add 100us grace time after regular
801 * regulator enable delay.
802 */
803 udelay(100);
804 }
805
806 ret = devm_add_action(&client->dev, zforce_reset, ts);
807 if (ret) {
808 dev_err(&client->dev, "failed to register reset action, %d\n",
809 ret);
810
811 /* hereafter the regulator will be disabled by the action */
812 if (!IS_ERR(ptr: ts->reg_vdd))
813 regulator_disable(regulator: ts->reg_vdd);
814
815 return ret;
816 }
817
818 snprintf(buf: ts->phys, size: sizeof(ts->phys),
819 fmt: "%s/input0", dev_name(dev: &client->dev));
820
821 input_dev = devm_input_allocate_device(&client->dev);
822 if (!input_dev) {
823 dev_err(&client->dev, "could not allocate input device\n");
824 return -ENOMEM;
825 }
826
827 mutex_init(&ts->access_mutex);
828 mutex_init(&ts->command_mutex);
829
830 ts->pdata = pdata;
831 ts->client = client;
832 ts->input = input_dev;
833
834 input_dev->name = "Neonode zForce touchscreen";
835 input_dev->phys = ts->phys;
836 input_dev->id.bustype = BUS_I2C;
837
838 input_dev->open = zforce_input_open;
839 input_dev->close = zforce_input_close;
840
841 __set_bit(EV_KEY, input_dev->evbit);
842 __set_bit(EV_SYN, input_dev->evbit);
843 __set_bit(EV_ABS, input_dev->evbit);
844
845 /* For multi touch */
846 input_set_abs_params(dev: input_dev, ABS_MT_POSITION_X, min: 0,
847 max: pdata->x_max, fuzz: 0, flat: 0);
848 input_set_abs_params(dev: input_dev, ABS_MT_POSITION_Y, min: 0,
849 max: pdata->y_max, fuzz: 0, flat: 0);
850
851 touchscreen_parse_properties(input: input_dev, multitouch: true, prop: &ts->prop);
852 if (ts->prop.max_x == 0 || ts->prop.max_y == 0) {
853 dev_err(&client->dev, "no size specified\n");
854 return -EINVAL;
855 }
856
857 input_set_abs_params(dev: input_dev, ABS_MT_TOUCH_MAJOR, min: 0,
858 ZFORCE_MAX_AREA, fuzz: 0, flat: 0);
859 input_set_abs_params(dev: input_dev, ABS_MT_TOUCH_MINOR, min: 0,
860 ZFORCE_MAX_AREA, fuzz: 0, flat: 0);
861 input_set_abs_params(dev: input_dev, ABS_MT_ORIENTATION, min: 0, max: 1, fuzz: 0, flat: 0);
862 input_mt_init_slots(dev: input_dev, ZFORCE_REPORT_POINTS, INPUT_MT_DIRECT);
863
864 input_set_drvdata(dev: ts->input, data: ts);
865
866 init_completion(x: &ts->command_done);
867
868 /*
869 * The zforce pulls the interrupt low when it has data ready.
870 * After it is triggered the isr thread runs until all the available
871 * packets have been read and the interrupt is high again.
872 * Therefore we can trigger the interrupt anytime it is low and do
873 * not need to limit it to the interrupt edge.
874 */
875 ret = devm_request_threaded_irq(dev: &client->dev, irq: client->irq,
876 handler: zforce_irq, thread_fn: zforce_irq_thread,
877 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
878 devname: input_dev->name, dev_id: ts);
879 if (ret) {
880 dev_err(&client->dev, "irq %d request failed\n", client->irq);
881 return ret;
882 }
883
884 i2c_set_clientdata(client, data: ts);
885
886 /* let the controller boot */
887 zforce_reset_deassert(ts);
888
889 ts->command_waiting = NOTIFICATION_BOOTCOMPLETE;
890 if (wait_for_completion_timeout(x: &ts->command_done, WAIT_TIMEOUT) == 0)
891 dev_warn(&client->dev, "bootcomplete timed out\n");
892
893 /* need to start device to get version information */
894 ret = zforce_command_wait(ts, COMMAND_INITIALIZE);
895 if (ret) {
896 dev_err(&client->dev, "unable to initialize, %d\n", ret);
897 return ret;
898 }
899
900 /* this gets the firmware version among other information */
901 ret = zforce_command_wait(ts, COMMAND_STATUS);
902 if (ret < 0) {
903 dev_err(&client->dev, "couldn't get status, %d\n", ret);
904 zforce_stop(ts);
905 return ret;
906 }
907
908 /* stop device and put it into sleep until it is opened */
909 ret = zforce_stop(ts);
910 if (ret < 0)
911 return ret;
912
913 device_set_wakeup_capable(dev: &client->dev, capable: true);
914
915 ret = input_register_device(input_dev);
916 if (ret) {
917 dev_err(&client->dev, "could not register input device, %d\n",
918 ret);
919 return ret;
920 }
921
922 return 0;
923}
924
925static struct i2c_device_id zforce_idtable[] = {
926 { "zforce-ts", 0 },
927 { }
928};
929MODULE_DEVICE_TABLE(i2c, zforce_idtable);
930
931#ifdef CONFIG_OF
932static const struct of_device_id zforce_dt_idtable[] = {
933 { .compatible = "neonode,zforce" },
934 {},
935};
936MODULE_DEVICE_TABLE(of, zforce_dt_idtable);
937#endif
938
939static struct i2c_driver zforce_driver = {
940 .driver = {
941 .name = "zforce-ts",
942 .pm = pm_sleep_ptr(&zforce_pm_ops),
943 .of_match_table = of_match_ptr(zforce_dt_idtable),
944 },
945 .probe = zforce_probe,
946 .id_table = zforce_idtable,
947};
948
949module_i2c_driver(zforce_driver);
950
951MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>");
952MODULE_DESCRIPTION("zForce TouchScreen Driver");
953MODULE_LICENSE("GPL");
954

source code of linux/drivers/input/touchscreen/zforce_ts.c