xref: /linux/drivers/input/touchscreen/silead.c (revision 2fe05e1139a555ae91f00a812cb9520e7d3022ab)
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_TOUCH_ID_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 
68 enum silead_ts_power {
69 	SILEAD_POWER_ON  = 1,
70 	SILEAD_POWER_OFF = 0
71 };
72 
73 struct 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 
87 struct silead_fw_data {
88 	u32 offset;
89 	u32 val;
90 };
91 
92 static 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 	data->input->name = SILEAD_TS_NAME;
113 	data->input->phys = "input/ts";
114 	data->input->id.bustype = BUS_I2C;
115 
116 	error = input_register_device(data->input);
117 	if (error) {
118 		dev_err(dev, "Failed to register input device: %d\n", error);
119 		return error;
120 	}
121 
122 	return 0;
123 }
124 
125 static void silead_ts_set_power(struct i2c_client *client,
126 				enum silead_ts_power state)
127 {
128 	struct silead_ts_data *data = i2c_get_clientdata(client);
129 
130 	if (data->gpio_power) {
131 		gpiod_set_value_cansleep(data->gpio_power, state);
132 		msleep(SILEAD_POWER_SLEEP);
133 	}
134 }
135 
136 static void silead_ts_read_data(struct i2c_client *client)
137 {
138 	struct silead_ts_data *data = i2c_get_clientdata(client);
139 	struct input_dev *input = data->input;
140 	struct device *dev = &client->dev;
141 	u8 *bufp, buf[SILEAD_TS_DATA_LEN];
142 	int touch_nr, error, i;
143 
144 	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_DATA,
145 					      SILEAD_TS_DATA_LEN, buf);
146 	if (error < 0) {
147 		dev_err(dev, "Data read error %d\n", error);
148 		return;
149 	}
150 
151 	touch_nr = buf[0];
152 	if (touch_nr > data->max_fingers) {
153 		dev_warn(dev, "More touches reported then supported %d > %d\n",
154 			 touch_nr, data->max_fingers);
155 		touch_nr = data->max_fingers;
156 	}
157 
158 	bufp = buf + SILEAD_POINT_DATA_LEN;
159 	for (i = 0; i < touch_nr; i++, bufp += SILEAD_POINT_DATA_LEN) {
160 		/* Bits 4-7 are the touch id */
161 		data->id[i] = (bufp[SILEAD_POINT_X_MSB_OFF] &
162 			       SILEAD_TOUCH_ID_MASK) >> 4;
163 		touchscreen_set_mt_pos(&data->pos[i], &data->prop,
164 			get_unaligned_le16(&bufp[SILEAD_POINT_X_OFF]) & 0xfff,
165 			get_unaligned_le16(&bufp[SILEAD_POINT_Y_OFF]) & 0xfff);
166 	}
167 
168 	input_mt_assign_slots(input, data->slots, data->pos, touch_nr, 0);
169 
170 	for (i = 0; i < touch_nr; i++) {
171 		input_mt_slot(input, data->slots[i]);
172 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
173 		input_report_abs(input, ABS_MT_POSITION_X, data->pos[i].x);
174 		input_report_abs(input, ABS_MT_POSITION_Y, data->pos[i].y);
175 
176 		dev_dbg(dev, "x=%d y=%d hw_id=%d sw_id=%d\n", data->pos[i].x,
177 			data->pos[i].y, data->id[i], data->slots[i]);
178 	}
179 
180 	input_mt_sync_frame(input);
181 	input_sync(input);
182 }
183 
184 static int silead_ts_init(struct i2c_client *client)
185 {
186 	struct silead_ts_data *data = i2c_get_clientdata(client);
187 	int error;
188 
189 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
190 					  SILEAD_CMD_RESET);
191 	if (error)
192 		goto i2c_write_err;
193 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
194 
195 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_TOUCH_NR,
196 					data->max_fingers);
197 	if (error)
198 		goto i2c_write_err;
199 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
200 
201 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
202 					  SILEAD_CLOCK);
203 	if (error)
204 		goto i2c_write_err;
205 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
206 
207 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
208 					  SILEAD_CMD_START);
209 	if (error)
210 		goto i2c_write_err;
211 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
212 
213 	return 0;
214 
215 i2c_write_err:
216 	dev_err(&client->dev, "Registers clear error %d\n", error);
217 	return error;
218 }
219 
220 static int silead_ts_reset(struct i2c_client *client)
221 {
222 	int error;
223 
224 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
225 					  SILEAD_CMD_RESET);
226 	if (error)
227 		goto i2c_write_err;
228 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
229 
230 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
231 					  SILEAD_CLOCK);
232 	if (error)
233 		goto i2c_write_err;
234 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
235 
236 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_POWER,
237 					  SILEAD_CMD_START);
238 	if (error)
239 		goto i2c_write_err;
240 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
241 
242 	return 0;
243 
244 i2c_write_err:
245 	dev_err(&client->dev, "Chip reset error %d\n", error);
246 	return error;
247 }
248 
249 static int silead_ts_startup(struct i2c_client *client)
250 {
251 	int error;
252 
253 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET, 0x00);
254 	if (error) {
255 		dev_err(&client->dev, "Startup error %d\n", error);
256 		return error;
257 	}
258 
259 	msleep(SILEAD_STARTUP_SLEEP);
260 
261 	return 0;
262 }
263 
264 static int silead_ts_load_fw(struct i2c_client *client)
265 {
266 	struct device *dev = &client->dev;
267 	struct silead_ts_data *data = i2c_get_clientdata(client);
268 	unsigned int fw_size, i;
269 	const struct firmware *fw;
270 	struct silead_fw_data *fw_data;
271 	int error;
272 
273 	dev_dbg(dev, "Firmware file name: %s", data->fw_name);
274 
275 	error = request_firmware(&fw, data->fw_name, dev);
276 	if (error) {
277 		dev_err(dev, "Firmware request error %d\n", error);
278 		return error;
279 	}
280 
281 	fw_size = fw->size / sizeof(*fw_data);
282 	fw_data = (struct silead_fw_data *)fw->data;
283 
284 	for (i = 0; i < fw_size; i++) {
285 		error = i2c_smbus_write_i2c_block_data(client,
286 						       fw_data[i].offset,
287 						       4,
288 						       (u8 *)&fw_data[i].val);
289 		if (error) {
290 			dev_err(dev, "Firmware load error %d\n", error);
291 			break;
292 		}
293 	}
294 
295 	release_firmware(fw);
296 	return error ?: 0;
297 }
298 
299 static u32 silead_ts_get_status(struct i2c_client *client)
300 {
301 	int error;
302 	__le32 status;
303 
304 	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_STATUS,
305 					      sizeof(status), (u8 *)&status);
306 	if (error < 0) {
307 		dev_err(&client->dev, "Status read error %d\n", error);
308 		return error;
309 	}
310 
311 	return le32_to_cpu(status);
312 }
313 
314 static int silead_ts_get_id(struct i2c_client *client)
315 {
316 	struct silead_ts_data *data = i2c_get_clientdata(client);
317 	__le32 chip_id;
318 	int error;
319 
320 	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_ID,
321 					      sizeof(chip_id), (u8 *)&chip_id);
322 	if (error < 0) {
323 		dev_err(&client->dev, "Chip ID read error %d\n", error);
324 		return error;
325 	}
326 
327 	data->chip_id = le32_to_cpu(chip_id);
328 	dev_info(&client->dev, "Silead chip ID: 0x%8X", data->chip_id);
329 
330 	return 0;
331 }
332 
333 static int silead_ts_setup(struct i2c_client *client)
334 {
335 	int error;
336 	u32 status;
337 
338 	silead_ts_set_power(client, SILEAD_POWER_OFF);
339 	silead_ts_set_power(client, SILEAD_POWER_ON);
340 
341 	error = silead_ts_get_id(client);
342 	if (error)
343 		return error;
344 
345 	error = silead_ts_init(client);
346 	if (error)
347 		return error;
348 
349 	error = silead_ts_reset(client);
350 	if (error)
351 		return error;
352 
353 	error = silead_ts_load_fw(client);
354 	if (error)
355 		return error;
356 
357 	error = silead_ts_startup(client);
358 	if (error)
359 		return error;
360 
361 	status = silead_ts_get_status(client);
362 	if (status != SILEAD_STATUS_OK) {
363 		dev_err(&client->dev,
364 			"Initialization error, status: 0x%X\n", status);
365 		return -ENODEV;
366 	}
367 
368 	return 0;
369 }
370 
371 static irqreturn_t silead_ts_threaded_irq_handler(int irq, void *id)
372 {
373 	struct silead_ts_data *data = id;
374 	struct i2c_client *client = data->client;
375 
376 	silead_ts_read_data(client);
377 
378 	return IRQ_HANDLED;
379 }
380 
381 static void silead_ts_read_props(struct i2c_client *client)
382 {
383 	struct silead_ts_data *data = i2c_get_clientdata(client);
384 	struct device *dev = &client->dev;
385 	const char *str;
386 	int error;
387 
388 	error = device_property_read_u32(dev, "silead,max-fingers",
389 					 &data->max_fingers);
390 	if (error) {
391 		dev_dbg(dev, "Max fingers read error %d\n", error);
392 		data->max_fingers = 5; /* Most devices handle up-to 5 fingers */
393 	}
394 
395 	error = device_property_read_string(dev, "firmware-name", &str);
396 	if (!error)
397 		snprintf(data->fw_name, sizeof(data->fw_name),
398 			 "silead/%s", str);
399 	else
400 		dev_dbg(dev, "Firmware file name read error. Using default.");
401 }
402 
403 #ifdef CONFIG_ACPI
404 static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
405 					 const struct i2c_device_id *id)
406 {
407 	const struct acpi_device_id *acpi_id;
408 	struct device *dev = &data->client->dev;
409 	int i;
410 
411 	if (ACPI_HANDLE(dev)) {
412 		acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
413 		if (!acpi_id)
414 			return -ENODEV;
415 
416 		snprintf(data->fw_name, sizeof(data->fw_name),
417 			 "silead/%s.fw", acpi_id->id);
418 
419 		for (i = 0; i < strlen(data->fw_name); i++)
420 			data->fw_name[i] = tolower(data->fw_name[i]);
421 	} else {
422 		snprintf(data->fw_name, sizeof(data->fw_name),
423 			 "silead/%s.fw", id->name);
424 	}
425 
426 	return 0;
427 }
428 #else
429 static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
430 					 const struct i2c_device_id *id)
431 {
432 	snprintf(data->fw_name, sizeof(data->fw_name),
433 		 "silead/%s.fw", id->name);
434 	return 0;
435 }
436 #endif
437 
438 static void silead_disable_regulator(void *arg)
439 {
440 	struct silead_ts_data *data = arg;
441 
442 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
443 }
444 
445 static int silead_ts_probe(struct i2c_client *client,
446 			   const struct i2c_device_id *id)
447 {
448 	struct silead_ts_data *data;
449 	struct device *dev = &client->dev;
450 	int error;
451 
452 	if (!i2c_check_functionality(client->adapter,
453 				     I2C_FUNC_I2C |
454 				     I2C_FUNC_SMBUS_READ_I2C_BLOCK |
455 				     I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
456 		dev_err(dev, "I2C functionality check failed\n");
457 		return -ENXIO;
458 	}
459 
460 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
461 	if (!data)
462 		return -ENOMEM;
463 
464 	i2c_set_clientdata(client, data);
465 	data->client = client;
466 
467 	error = silead_ts_set_default_fw_name(data, id);
468 	if (error)
469 		return error;
470 
471 	silead_ts_read_props(client);
472 
473 	/* We must have the IRQ provided by DT or ACPI subsytem */
474 	if (client->irq <= 0)
475 		return -ENODEV;
476 
477 	data->regulators[0].supply = "vddio";
478 	data->regulators[1].supply = "avdd";
479 	error = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
480 					data->regulators);
481 	if (error)
482 		return error;
483 
484 	/*
485 	 * Enable regulators at probe and disable them at remove, we need
486 	 * to keep the chip powered otherwise it forgets its firmware.
487 	 */
488 	error = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
489 				      data->regulators);
490 	if (error)
491 		return error;
492 
493 	error = devm_add_action_or_reset(dev, silead_disable_regulator, data);
494 	if (error)
495 		return error;
496 
497 	/* Power GPIO pin */
498 	data->gpio_power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
499 	if (IS_ERR(data->gpio_power)) {
500 		if (PTR_ERR(data->gpio_power) != -EPROBE_DEFER)
501 			dev_err(dev, "Shutdown GPIO request failed\n");
502 		return PTR_ERR(data->gpio_power);
503 	}
504 
505 	error = silead_ts_setup(client);
506 	if (error)
507 		return error;
508 
509 	error = silead_ts_request_input_dev(data);
510 	if (error)
511 		return error;
512 
513 	error = devm_request_threaded_irq(dev, client->irq,
514 					  NULL, silead_ts_threaded_irq_handler,
515 					  IRQF_ONESHOT, client->name, data);
516 	if (error) {
517 		if (error != -EPROBE_DEFER)
518 			dev_err(dev, "IRQ request failed %d\n", error);
519 		return error;
520 	}
521 
522 	return 0;
523 }
524 
525 static int __maybe_unused silead_ts_suspend(struct device *dev)
526 {
527 	struct i2c_client *client = to_i2c_client(dev);
528 
529 	disable_irq(client->irq);
530 	silead_ts_set_power(client, SILEAD_POWER_OFF);
531 	return 0;
532 }
533 
534 static int __maybe_unused silead_ts_resume(struct device *dev)
535 {
536 	struct i2c_client *client = to_i2c_client(dev);
537 	int error, status;
538 
539 	silead_ts_set_power(client, SILEAD_POWER_ON);
540 
541 	error = silead_ts_reset(client);
542 	if (error)
543 		return error;
544 
545 	error = silead_ts_startup(client);
546 	if (error)
547 		return error;
548 
549 	status = silead_ts_get_status(client);
550 	if (status != SILEAD_STATUS_OK) {
551 		dev_err(dev, "Resume error, status: 0x%02x\n", status);
552 		return -ENODEV;
553 	}
554 
555 	enable_irq(client->irq);
556 
557 	return 0;
558 }
559 
560 static SIMPLE_DEV_PM_OPS(silead_ts_pm, silead_ts_suspend, silead_ts_resume);
561 
562 static const struct i2c_device_id silead_ts_id[] = {
563 	{ "gsl1680", 0 },
564 	{ "gsl1688", 0 },
565 	{ "gsl3670", 0 },
566 	{ "gsl3675", 0 },
567 	{ "gsl3692", 0 },
568 	{ "mssl1680", 0 },
569 	{ }
570 };
571 MODULE_DEVICE_TABLE(i2c, silead_ts_id);
572 
573 #ifdef CONFIG_ACPI
574 static const struct acpi_device_id silead_ts_acpi_match[] = {
575 	{ "GSL1680", 0 },
576 	{ "GSL1688", 0 },
577 	{ "GSL3670", 0 },
578 	{ "GSL3675", 0 },
579 	{ "GSL3692", 0 },
580 	{ "MSSL1680", 0 },
581 	{ }
582 };
583 MODULE_DEVICE_TABLE(acpi, silead_ts_acpi_match);
584 #endif
585 
586 #ifdef CONFIG_OF
587 static const struct of_device_id silead_ts_of_match[] = {
588 	{ .compatible = "silead,gsl1680" },
589 	{ .compatible = "silead,gsl1688" },
590 	{ .compatible = "silead,gsl3670" },
591 	{ .compatible = "silead,gsl3675" },
592 	{ .compatible = "silead,gsl3692" },
593 	{ },
594 };
595 MODULE_DEVICE_TABLE(of, silead_ts_of_match);
596 #endif
597 
598 static struct i2c_driver silead_ts_driver = {
599 	.probe = silead_ts_probe,
600 	.id_table = silead_ts_id,
601 	.driver = {
602 		.name = SILEAD_TS_NAME,
603 		.acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
604 		.of_match_table = of_match_ptr(silead_ts_of_match),
605 		.pm = &silead_ts_pm,
606 	},
607 };
608 module_i2c_driver(silead_ts_driver);
609 
610 MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
611 MODULE_DESCRIPTION("Silead I2C touchscreen driver");
612 MODULE_LICENSE("GPL");
613