1/* -------------------------------------------------------------------------
2 * Copyright (C) 2014-2015, Intel Corporation
3 *
4 * Derived from:
5 * gslX68X.c
6 * Copyright (C) 2010-2015, Shanghai Sileadinc Co.Ltd
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 * -------------------------------------------------------------------------
18 */
19
20#include <linux/i2c.h>
21#include <linux/module.h>
22#include <linux/acpi.h>
23#include <linux/interrupt.h>
24#include <linux/gpio/consumer.h>
25#include <linux/delay.h>
26#include <linux/firmware.h>
27#include <linux/input.h>
28#include <linux/input/mt.h>
29#include <linux/input/touchscreen.h>
30#include <linux/pm.h>
31#include <linux/irq.h>
32#include <linux/regulator/consumer.h>
33
34#include <asm/unaligned.h>
35
36#define SILEAD_TS_NAME "silead_ts"
37
38#define SILEAD_REG_RESET 0xE0
39#define SILEAD_REG_DATA 0x80
40#define SILEAD_REG_TOUCH_NR 0x80
41#define SILEAD_REG_POWER 0xBC
42#define SILEAD_REG_CLOCK 0xE4
43#define SILEAD_REG_STATUS 0xB0
44#define SILEAD_REG_ID 0xFC
45#define SILEAD_REG_MEM_CHECK 0xB0
46
47#define SILEAD_STATUS_OK 0x5A5A5A5A
48#define SILEAD_TS_DATA_LEN 44
49#define SILEAD_CLOCK 0x04
50
51#define SILEAD_CMD_RESET 0x88
52#define SILEAD_CMD_START 0x00
53
54#define SILEAD_POINT_DATA_LEN 0x04
55#define SILEAD_POINT_Y_OFF 0x00
56#define SILEAD_POINT_Y_MSB_OFF 0x01
57#define SILEAD_POINT_X_OFF 0x02
58#define SILEAD_POINT_X_MSB_OFF 0x03
59#define SILEAD_EXTRA_DATA_MASK 0xF0
60
61#define SILEAD_CMD_SLEEP_MIN 10000
62#define SILEAD_CMD_SLEEP_MAX 20000
63#define SILEAD_POWER_SLEEP 20
64#define SILEAD_STARTUP_SLEEP 30
65
66#define SILEAD_MAX_FINGERS 10
67
68enum silead_ts_power {
69 SILEAD_POWER_ON = 1,
70 SILEAD_POWER_OFF = 0
71};
72
73struct silead_ts_data {
74 struct i2c_client *client;
75 struct gpio_desc *gpio_power;
76 struct input_dev *input;
77 struct regulator_bulk_data regulators[2];
78 char fw_name[64];
79 struct touchscreen_properties prop;
80 u32 max_fingers;
81 u32 chip_id;
82 struct input_mt_pos pos[SILEAD_MAX_FINGERS];
83 int slots[SILEAD_MAX_FINGERS];
84 int id[SILEAD_MAX_FINGERS];
85};
86
87struct silead_fw_data {
88 u32 offset;
89 u32 val;
90};
91
92static int silead_ts_request_input_dev(struct silead_ts_data *data)
93{
94 struct device *dev = &data->client->dev;
95 int error;
96
97 data->input = devm_input_allocate_device(dev);
98 if (!data->input) {
99 dev_err(dev,
100 "Failed to allocate input device\n");
101 return -ENOMEM;
102 }
103
104 input_set_abs_params(data->input, ABS_MT_POSITION_X, 0, 4095, 0, 0);
105 input_set_abs_params(data->input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
106 touchscreen_parse_properties(data->input, true, &data->prop);
107
108 input_mt_init_slots(data->input, data->max_fingers,
109 INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED |
110 INPUT_MT_TRACK);
111
112 if (device_property_read_bool(dev, "silead,home-button"))
113 input_set_capability(data->input, EV_KEY, KEY_LEFTMETA);
114
115 data->input->name = SILEAD_TS_NAME;
116 data->input->phys = "input/ts";
117 data->input->id.bustype = BUS_I2C;
118
119 error = input_register_device(data->input);
120 if (error) {
121 dev_err(dev, "Failed to register input device: %d\n", error);
122 return error;
123 }
124
125 return 0;
126}
127
128static void silead_ts_set_power(struct i2c_client *client,
129 enum silead_ts_power state)
130{
131 struct silead_ts_data *data = i2c_get_clientdata(client);
132
133 if (data->gpio_power) {
134 gpiod_set_value_cansleep(data->gpio_power, state);
135 msleep(SILEAD_POWER_SLEEP);
136 }
137}
138
139static void silead_ts_read_data(struct i2c_client *client)
140{
141 struct silead_ts_data *data = i2c_get_clientdata(client);
142 struct input_dev *input = data->input;
143 struct device *dev = &client->dev;
144 u8 *bufp, buf[SILEAD_TS_DATA_LEN];
145 int touch_nr, softbutton, error, i;
146 bool softbutton_pressed = false;
147
148 error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_DATA,
149 SILEAD_TS_DATA_LEN, buf);
150 if (error < 0) {
151 dev_err(dev, "Data read error %d\n", error);
152 return;
153 }
154
155 if (buf[0] > data->max_fingers) {
156 dev_warn(dev, "More touches reported then supported %d > %d\n",
157 buf[0], data->max_fingers);
158 buf[0] = data->max_fingers;
159 }
160
161 touch_nr = 0;
162 bufp = buf + SILEAD_POINT_DATA_LEN;
163 for (i = 0; i < buf[0]; i++, bufp += SILEAD_POINT_DATA_LEN) {
164 softbutton = (bufp[SILEAD_POINT_Y_MSB_OFF] &
165 SILEAD_EXTRA_DATA_MASK) >> 4;
166
167 if (softbutton) {
168 /*
169 * For now only respond to softbutton == 0x01, some
170 * tablets *without* a capacative button send 0x04
171 * when crossing the edges of the screen.
172 */
173 if (softbutton == 0x01)
174 softbutton_pressed = true;
175
176 continue;
177 }
178
179 /*
180 * Bits 4-7 are the touch id, note not all models have
181 * hardware touch ids so atm we don't use these.
182 */
183 data->id[touch_nr] = (bufp[SILEAD_POINT_X_MSB_OFF] &
184 SILEAD_EXTRA_DATA_MASK) >> 4;
185 touchscreen_set_mt_pos(&data->pos[touch_nr], &data->prop,
186 get_unaligned_le16(&bufp[SILEAD_POINT_X_OFF]) & 0xfff,
187 get_unaligned_le16(&bufp[SILEAD_POINT_Y_OFF]) & 0xfff);
188 touch_nr++;
189 }
190
191 input_mt_assign_slots(input, data->slots, data->pos, touch_nr, 0);
192
193 for (i = 0; i < touch_nr; i++) {
194 input_mt_slot(input, data->slots[i]);
195 input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
196 input_report_abs(input, ABS_MT_POSITION_X, data->pos[i].x);
197 input_report_abs(input, ABS_MT_POSITION_Y, data->pos[i].y);
198
199 dev_dbg(dev, "x=%d y=%d hw_id=%d sw_id=%d\n", data->pos[i].x,
200 data->pos[i].y, data->id[i], data->slots[i]);
201 }
202
203 input_mt_sync_frame(input);
204 input_report_key(input, KEY_LEFTMETA, softbutton_pressed);
205 input_sync(input);
206}
207
208static int silead_ts_init(struct i2c_client *client)
209{
210 struct silead_ts_data *data = i2c_get_clientdata(client);
211 int error;
212
213 error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
214 SILEAD_CMD_RESET);
215 if (error)
216 goto i2c_write_err;
217 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
218
219 error = i2c_smbus_write_byte_data(client, SILEAD_REG_TOUCH_NR,
220 data->max_fingers);
221 if (error)
222 goto i2c_write_err;
223 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
224
225 error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
226 SILEAD_CLOCK);
227 if (error)
228 goto i2c_write_err;
229 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
230
231 error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
232 SILEAD_CMD_START);
233 if (error)
234 goto i2c_write_err;
235 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
236
237 return 0;
238
239i2c_write_err:
240 dev_err(&client->dev, "Registers clear error %d\n", error);
241 return error;
242}
243
244static int silead_ts_reset(struct i2c_client *client)
245{
246 int error;
247
248 error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
249 SILEAD_CMD_RESET);
250 if (error)
251 goto i2c_write_err;
252 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
253
254 error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
255 SILEAD_CLOCK);
256 if (error)
257 goto i2c_write_err;
258 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
259
260 error = i2c_smbus_write_byte_data(client, SILEAD_REG_POWER,
261 SILEAD_CMD_START);
262 if (error)
263 goto i2c_write_err;
264 usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
265
266 return 0;
267
268i2c_write_err:
269 dev_err(&client->dev, "Chip reset error %d\n", error);
270 return error;
271}
272
273static int silead_ts_startup(struct i2c_client *client)
274{
275 int error;
276
277 error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET, 0x00);
278 if (error) {
279 dev_err(&client->dev, "Startup error %d\n", error);
280 return error;
281 }
282
283 msleep(SILEAD_STARTUP_SLEEP);
284
285 return 0;
286}
287
288static int silead_ts_load_fw(struct i2c_client *client)
289{
290 struct device *dev = &client->dev;
291 struct silead_ts_data *data = i2c_get_clientdata(client);
292 unsigned int fw_size, i;
293 const struct firmware *fw;
294 struct silead_fw_data *fw_data;
295 int error;
296
297 dev_dbg(dev, "Firmware file name: %s", data->fw_name);
298
299 error = request_firmware(&fw, data->fw_name, dev);
300 if (error) {
301 dev_err(dev, "Firmware request error %d\n", error);
302 return error;
303 }
304
305 fw_size = fw->size / sizeof(*fw_data);
306 fw_data = (struct silead_fw_data *)fw->data;
307
308 for (i = 0; i < fw_size; i++) {
309 error = i2c_smbus_write_i2c_block_data(client,
310 fw_data[i].offset,
311 4,
312 (u8 *)&fw_data[i].val);
313 if (error) {
314 dev_err(dev, "Firmware load error %d\n", error);
315 break;
316 }
317 }
318
319 release_firmware(fw);
320 return error ?: 0;
321}
322
323static u32 silead_ts_get_status(struct i2c_client *client)
324{
325 int error;
326 __le32 status;
327
328 error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_STATUS,
329 sizeof(status), (u8 *)&status);
330 if (error < 0) {
331 dev_err(&client->dev, "Status read error %d\n", error);
332 return error;
333 }
334
335 return le32_to_cpu(status);
336}
337
338static int silead_ts_get_id(struct i2c_client *client)
339{
340 struct silead_ts_data *data = i2c_get_clientdata(client);
341 __le32 chip_id;
342 int error;
343
344 error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_ID,
345 sizeof(chip_id), (u8 *)&chip_id);
346 if (error < 0) {
347 dev_err(&client->dev, "Chip ID read error %d\n", error);
348 return error;
349 }
350
351 data->chip_id = le32_to_cpu(chip_id);
352 dev_info(&client->dev, "Silead chip ID: 0x%8X", data->chip_id);
353
354 return 0;
355}
356
357static int silead_ts_setup(struct i2c_client *client)
358{
359 int error;
360 u32 status;
361
362 silead_ts_set_power(client, SILEAD_POWER_OFF);
363 silead_ts_set_power(client, SILEAD_POWER_ON);
364
365 error = silead_ts_get_id(client);
366 if (error)
367 return error;
368
369 error = silead_ts_init(client);
370 if (error)
371 return error;
372
373 error = silead_ts_reset(client);
374 if (error)
375 return error;
376
377 error = silead_ts_load_fw(client);
378 if (error)
379 return error;
380
381 error = silead_ts_startup(client);
382 if (error)
383 return error;
384
385 status = silead_ts_get_status(client);
386 if (status != SILEAD_STATUS_OK) {
387 dev_err(&client->dev,
388 "Initialization error, status: 0x%X\n", status);
389 return -ENODEV;
390 }
391
392 return 0;
393}
394
395static irqreturn_t silead_ts_threaded_irq_handler(int irq, void *id)
396{
397 struct silead_ts_data *data = id;
398 struct i2c_client *client = data->client;
399
400 silead_ts_read_data(client);
401
402 return IRQ_HANDLED;
403}
404
405static void silead_ts_read_props(struct i2c_client *client)
406{
407 struct silead_ts_data *data = i2c_get_clientdata(client);
408 struct device *dev = &client->dev;
409 const char *str;
410 int error;
411
412 error = device_property_read_u32(dev, "silead,max-fingers",
413 &data->max_fingers);
414 if (error) {
415 dev_dbg(dev, "Max fingers read error %d\n", error);
416 data->max_fingers = 5; /* Most devices handle up-to 5 fingers */
417 }
418
419 error = device_property_read_string(dev, "firmware-name", &str);
420 if (!error)
421 snprintf(data->fw_name, sizeof(data->fw_name),
422 "silead/%s", str);
423 else
424 dev_dbg(dev, "Firmware file name read error. Using default.");
425}
426
427#ifdef CONFIG_ACPI
428static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
429 const struct i2c_device_id *id)
430{
431 const struct acpi_device_id *acpi_id;
432 struct device *dev = &data->client->dev;
433 int i;
434
435 if (ACPI_HANDLE(dev)) {
436 acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
437 if (!acpi_id)
438 return -ENODEV;
439
440 snprintf(data->fw_name, sizeof(data->fw_name),
441 "silead/%s.fw", acpi_id->id);
442
443 for (i = 0; i < strlen(data->fw_name); i++)
444 data->fw_name[i] = tolower(data->fw_name[i]);
445 } else {
446 snprintf(data->fw_name, sizeof(data->fw_name),
447 "silead/%s.fw", id->name);
448 }
449
450 return 0;
451}
452#else
453static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
454 const struct i2c_device_id *id)
455{
456 snprintf(data->fw_name, sizeof(data->fw_name),
457 "silead/%s.fw", id->name);
458 return 0;
459}
460#endif
461
462static void silead_disable_regulator(void *arg)
463{
464 struct silead_ts_data *data = arg;
465
466 regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
467}
468
469static int silead_ts_probe(struct i2c_client *client,
470 const struct i2c_device_id *id)
471{
472 struct silead_ts_data *data;
473 struct device *dev = &client->dev;
474 int error;
475
476 if (!i2c_check_functionality(client->adapter,
477 I2C_FUNC_I2C |
478 I2C_FUNC_SMBUS_READ_I2C_BLOCK |
479 I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
480 dev_err(dev, "I2C functionality check failed\n");
481 return -ENXIO;
482 }
483
484 data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
485 if (!data)
486 return -ENOMEM;
487
488 i2c_set_clientdata(client, data);
489 data->client = client;
490
491 error = silead_ts_set_default_fw_name(data, id);
492 if (error)
493 return error;
494
495 silead_ts_read_props(client);
496
497 /* We must have the IRQ provided by DT or ACPI subsytem */
498 if (client->irq <= 0)
499 return -ENODEV;
500
501 data->regulators[0].supply = "vddio";
502 data->regulators[1].supply = "avdd";
503 error = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
504 data->regulators);
505 if (error)
506 return error;
507
508 /*
509 * Enable regulators at probe and disable them at remove, we need
510 * to keep the chip powered otherwise it forgets its firmware.
511 */
512 error = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
513 data->regulators);
514 if (error)
515 return error;
516
517 error = devm_add_action_or_reset(dev, silead_disable_regulator, data);
518 if (error)
519 return error;
520
521 /* Power GPIO pin */
522 data->gpio_power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
523 if (IS_ERR(data->gpio_power)) {
524 if (PTR_ERR(data->gpio_power) != -EPROBE_DEFER)
525 dev_err(dev, "Shutdown GPIO request failed\n");
526 return PTR_ERR(data->gpio_power);
527 }
528
529 error = silead_ts_setup(client);
530 if (error)
531 return error;
532
533 error = silead_ts_request_input_dev(data);
534 if (error)
535 return error;
536
537 error = devm_request_threaded_irq(dev, client->irq,
538 NULL, silead_ts_threaded_irq_handler,
539 IRQF_ONESHOT, client->name, data);
540 if (error) {
541 if (error != -EPROBE_DEFER)
542 dev_err(dev, "IRQ request failed %d\n", error);
543 return error;
544 }
545
546 return 0;
547}
548
549static int __maybe_unused silead_ts_suspend(struct device *dev)
550{
551 struct i2c_client *client = to_i2c_client(dev);
552
553 disable_irq(client->irq);
554 silead_ts_set_power(client, SILEAD_POWER_OFF);
555 return 0;
556}
557
558static int __maybe_unused silead_ts_resume(struct device *dev)
559{
560 struct i2c_client *client = to_i2c_client(dev);
561 bool second_try = false;
562 int error, status;
563
564 silead_ts_set_power(client, SILEAD_POWER_ON);
565
566 retry:
567 error = silead_ts_reset(client);
568 if (error)
569 return error;
570
571 if (second_try) {
572 error = silead_ts_load_fw(client);
573 if (error)
574 return error;
575 }
576
577 error = silead_ts_startup(client);
578 if (error)
579 return error;
580
581 status = silead_ts_get_status(client);
582 if (status != SILEAD_STATUS_OK) {
583 if (!second_try) {
584 second_try = true;
585 dev_dbg(dev, "Reloading firmware after unsuccessful resume\n");
586 goto retry;
587 }
588 dev_err(dev, "Resume error, status: 0x%02x\n", status);
589 return -ENODEV;
590 }
591
592 enable_irq(client->irq);
593
594 return 0;
595}
596
597static SIMPLE_DEV_PM_OPS(silead_ts_pm, silead_ts_suspend, silead_ts_resume);
598
599static const struct i2c_device_id silead_ts_id[] = {
600 { "gsl1680", 0 },
601 { "gsl1688", 0 },
602 { "gsl3670", 0 },
603 { "gsl3675", 0 },
604 { "gsl3692", 0 },
605 { "mssl1680", 0 },
606 { }
607};
608MODULE_DEVICE_TABLE(i2c, silead_ts_id);
609
610#ifdef CONFIG_ACPI
611static const struct acpi_device_id silead_ts_acpi_match[] = {
612 { "GSL1680", 0 },
613 { "GSL1688", 0 },
614 { "GSL3670", 0 },
615 { "GSL3675", 0 },
616 { "GSL3692", 0 },
617 { "MSSL1680", 0 },
618 { "MSSL0001", 0 },
619 { "MSSL0002", 0 },
620 { }
621};
622MODULE_DEVICE_TABLE(acpi, silead_ts_acpi_match);
623#endif
624
625#ifdef CONFIG_OF
626static const struct of_device_id silead_ts_of_match[] = {
627 { .compatible = "silead,gsl1680" },
628 { .compatible = "silead,gsl1688" },
629 { .compatible = "silead,gsl3670" },
630 { .compatible = "silead,gsl3675" },
631 { .compatible = "silead,gsl3692" },
632 { },
633};
634MODULE_DEVICE_TABLE(of, silead_ts_of_match);
635#endif
636
637static struct i2c_driver silead_ts_driver = {
638 .probe = silead_ts_probe,
639 .id_table = silead_ts_id,
640 .driver = {
641 .name = SILEAD_TS_NAME,
642 .acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
643 .of_match_table = of_match_ptr(silead_ts_of_match),
644 .pm = &silead_ts_pm,
645 },
646};
647module_i2c_driver(silead_ts_driver);
648
649MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
650MODULE_DESCRIPTION("Silead I2C touchscreen driver");
651MODULE_LICENSE("GPL");
652