1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* -------------------------------------------------------------------------
3  * Copyright (C) 2014-2015, Intel Corporation
4  *
5  * Derived from:
6  *  gslX68X.c
7  *  Copyright (C) 2010-2015, Shanghai Sileadinc Co.Ltd
8  *
9  * -------------------------------------------------------------------------
10  */
11 
12 #include <linux/i2c.h>
13 #include <linux/module.h>
14 #include <linux/acpi.h>
15 #include <linux/interrupt.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/delay.h>
18 #include <linux/firmware.h>
19 #include <linux/input.h>
20 #include <linux/input/mt.h>
21 #include <linux/input/touchscreen.h>
22 #include <linux/pm.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/irq.h>
25 #include <linux/regulator/consumer.h>
26 
27 #include <asm/unaligned.h>
28 
29 #define SILEAD_TS_NAME		"silead_ts"
30 
31 #define SILEAD_REG_RESET	0xE0
32 #define SILEAD_REG_DATA		0x80
33 #define SILEAD_REG_TOUCH_NR	0x80
34 #define SILEAD_REG_POWER	0xBC
35 #define SILEAD_REG_CLOCK	0xE4
36 #define SILEAD_REG_STATUS	0xB0
37 #define SILEAD_REG_ID		0xFC
38 #define SILEAD_REG_MEM_CHECK	0xB0
39 
40 #define SILEAD_STATUS_OK	0x5A5A5A5A
41 #define SILEAD_TS_DATA_LEN	44
42 #define SILEAD_CLOCK		0x04
43 
44 #define SILEAD_CMD_RESET	0x88
45 #define SILEAD_CMD_START	0x00
46 
47 #define SILEAD_POINT_DATA_LEN	0x04
48 #define SILEAD_POINT_Y_OFF      0x00
49 #define SILEAD_POINT_Y_MSB_OFF	0x01
50 #define SILEAD_POINT_X_OFF	0x02
51 #define SILEAD_POINT_X_MSB_OFF	0x03
52 #define SILEAD_EXTRA_DATA_MASK	0xF0
53 
54 #define SILEAD_CMD_SLEEP_MIN	10000
55 #define SILEAD_CMD_SLEEP_MAX	20000
56 #define SILEAD_POWER_SLEEP	20
57 #define SILEAD_STARTUP_SLEEP	30
58 
59 #define SILEAD_MAX_FINGERS	10
60 
61 enum silead_ts_power {
62 	SILEAD_POWER_ON  = 1,
63 	SILEAD_POWER_OFF = 0
64 };
65 
66 struct silead_ts_data {
67 	struct i2c_client *client;
68 	struct gpio_desc *gpio_power;
69 	struct input_dev *input;
70 	struct input_dev *pen_input;
71 	struct regulator_bulk_data regulators[2];
72 	char fw_name[64];
73 	struct touchscreen_properties prop;
74 	u32 max_fingers;
75 	u32 chip_id;
76 	struct input_mt_pos pos[SILEAD_MAX_FINGERS];
77 	int slots[SILEAD_MAX_FINGERS];
78 	int id[SILEAD_MAX_FINGERS];
79 	u32 efi_fw_min_max[4];
80 	bool efi_fw_min_max_set;
81 	bool pen_supported;
82 	bool pen_down;
83 	u32 pen_x_res;
84 	u32 pen_y_res;
85 	int pen_up_count;
86 };
87 
88 struct silead_fw_data {
89 	u32 offset;
90 	u32 val;
91 };
92 
silead_apply_efi_fw_min_max(struct silead_ts_data * data)93 static void silead_apply_efi_fw_min_max(struct silead_ts_data *data)
94 {
95 	struct input_absinfo *absinfo_x = &data->input->absinfo[ABS_MT_POSITION_X];
96 	struct input_absinfo *absinfo_y = &data->input->absinfo[ABS_MT_POSITION_Y];
97 
98 	if (!data->efi_fw_min_max_set)
99 		return;
100 
101 	absinfo_x->minimum = data->efi_fw_min_max[0];
102 	absinfo_x->maximum = data->efi_fw_min_max[1];
103 	absinfo_y->minimum = data->efi_fw_min_max[2];
104 	absinfo_y->maximum = data->efi_fw_min_max[3];
105 
106 	if (data->prop.invert_x) {
107 		absinfo_x->maximum -= absinfo_x->minimum;
108 		absinfo_x->minimum = 0;
109 	}
110 
111 	if (data->prop.invert_y) {
112 		absinfo_y->maximum -= absinfo_y->minimum;
113 		absinfo_y->minimum = 0;
114 	}
115 
116 	if (data->prop.swap_x_y) {
117 		swap(absinfo_x->minimum, absinfo_y->minimum);
118 		swap(absinfo_x->maximum, absinfo_y->maximum);
119 	}
120 }
121 
silead_ts_request_input_dev(struct silead_ts_data * data)122 static int silead_ts_request_input_dev(struct silead_ts_data *data)
123 {
124 	struct device *dev = &data->client->dev;
125 	int error;
126 
127 	data->input = devm_input_allocate_device(dev);
128 	if (!data->input) {
129 		dev_err(dev,
130 			"Failed to allocate input device\n");
131 		return -ENOMEM;
132 	}
133 
134 	input_set_abs_params(data->input, ABS_MT_POSITION_X, 0, 4095, 0, 0);
135 	input_set_abs_params(data->input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
136 	touchscreen_parse_properties(data->input, true, &data->prop);
137 	silead_apply_efi_fw_min_max(data);
138 
139 	input_mt_init_slots(data->input, data->max_fingers,
140 			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED |
141 			    INPUT_MT_TRACK);
142 
143 	if (device_property_read_bool(dev, "silead,home-button"))
144 		input_set_capability(data->input, EV_KEY, KEY_LEFTMETA);
145 
146 	data->input->name = SILEAD_TS_NAME;
147 	data->input->phys = "input/ts";
148 	data->input->id.bustype = BUS_I2C;
149 
150 	error = input_register_device(data->input);
151 	if (error) {
152 		dev_err(dev, "Failed to register input device: %d\n", error);
153 			return error;
154 	}
155 
156 	return 0;
157 }
158 
silead_ts_request_pen_input_dev(struct silead_ts_data * data)159 static int silead_ts_request_pen_input_dev(struct silead_ts_data *data)
160 {
161 	struct device *dev = &data->client->dev;
162 	int error;
163 
164 	if (!data->pen_supported)
165 		return 0;
166 
167 	data->pen_input = devm_input_allocate_device(dev);
168 	if (!data->pen_input)
169 		return -ENOMEM;
170 
171 	input_set_abs_params(data->pen_input, ABS_X, 0, 4095, 0, 0);
172 	input_set_abs_params(data->pen_input, ABS_Y, 0, 4095, 0, 0);
173 	input_set_capability(data->pen_input, EV_KEY, BTN_TOUCH);
174 	input_set_capability(data->pen_input, EV_KEY, BTN_TOOL_PEN);
175 	set_bit(INPUT_PROP_DIRECT, data->pen_input->propbit);
176 	touchscreen_parse_properties(data->pen_input, false, &data->prop);
177 	input_abs_set_res(data->pen_input, ABS_X, data->pen_x_res);
178 	input_abs_set_res(data->pen_input, ABS_Y, data->pen_y_res);
179 
180 	data->pen_input->name = SILEAD_TS_NAME " pen";
181 	data->pen_input->phys = "input/pen";
182 	data->input->id.bustype = BUS_I2C;
183 
184 	error = input_register_device(data->pen_input);
185 	if (error) {
186 		dev_err(dev, "Failed to register pen input device: %d\n", error);
187 		return error;
188 	}
189 
190 	return 0;
191 }
192 
silead_ts_set_power(struct i2c_client * client,enum silead_ts_power state)193 static void silead_ts_set_power(struct i2c_client *client,
194 				enum silead_ts_power state)
195 {
196 	struct silead_ts_data *data = i2c_get_clientdata(client);
197 
198 	if (data->gpio_power) {
199 		gpiod_set_value_cansleep(data->gpio_power, state);
200 		msleep(SILEAD_POWER_SLEEP);
201 	}
202 }
203 
silead_ts_handle_pen_data(struct silead_ts_data * data,u8 * buf)204 static bool silead_ts_handle_pen_data(struct silead_ts_data *data, u8 *buf)
205 {
206 	u8 *coord = buf + SILEAD_POINT_DATA_LEN;
207 	struct input_mt_pos pos;
208 
209 	if (!data->pen_supported || buf[2] != 0x00 || buf[3] != 0x00)
210 		return false;
211 
212 	if (buf[0] == 0x00 && buf[1] == 0x00 && data->pen_down) {
213 		data->pen_up_count++;
214 		if (data->pen_up_count == 6) {
215 			data->pen_down = false;
216 			goto sync;
217 		}
218 		return true;
219 	}
220 
221 	if (buf[0] == 0x01 && buf[1] == 0x08) {
222 		touchscreen_set_mt_pos(&pos, &data->prop,
223 			get_unaligned_le16(&coord[SILEAD_POINT_X_OFF]) & 0xfff,
224 			get_unaligned_le16(&coord[SILEAD_POINT_Y_OFF]) & 0xfff);
225 
226 		input_report_abs(data->pen_input, ABS_X, pos.x);
227 		input_report_abs(data->pen_input, ABS_Y, pos.y);
228 
229 		data->pen_up_count = 0;
230 		data->pen_down = true;
231 		goto sync;
232 	}
233 
234 	return false;
235 
236 sync:
237 	input_report_key(data->pen_input, BTN_TOOL_PEN, data->pen_down);
238 	input_report_key(data->pen_input, BTN_TOUCH, data->pen_down);
239 	input_sync(data->pen_input);
240 	return true;
241 }
242 
silead_ts_read_data(struct i2c_client * client)243 static void silead_ts_read_data(struct i2c_client *client)
244 {
245 	struct silead_ts_data *data = i2c_get_clientdata(client);
246 	struct input_dev *input = data->input;
247 	struct device *dev = &client->dev;
248 	u8 *bufp, buf[SILEAD_TS_DATA_LEN];
249 	int touch_nr, softbutton, error, i;
250 	bool softbutton_pressed = false;
251 
252 	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_DATA,
253 					      SILEAD_TS_DATA_LEN, buf);
254 	if (error < 0) {
255 		dev_err(dev, "Data read error %d\n", error);
256 		return;
257 	}
258 
259 	if (buf[0] > data->max_fingers) {
260 		dev_warn(dev, "More touches reported then supported %d > %d\n",
261 			 buf[0], data->max_fingers);
262 		buf[0] = data->max_fingers;
263 	}
264 
265 	if (silead_ts_handle_pen_data(data, buf))
266 		goto sync; /* Pen is down, release all previous touches */
267 
268 	touch_nr = 0;
269 	bufp = buf + SILEAD_POINT_DATA_LEN;
270 	for (i = 0; i < buf[0]; i++, bufp += SILEAD_POINT_DATA_LEN) {
271 		softbutton = (bufp[SILEAD_POINT_Y_MSB_OFF] &
272 			      SILEAD_EXTRA_DATA_MASK) >> 4;
273 
274 		if (softbutton) {
275 			/*
276 			 * For now only respond to softbutton == 0x01, some
277 			 * tablets *without* a capacative button send 0x04
278 			 * when crossing the edges of the screen.
279 			 */
280 			if (softbutton == 0x01)
281 				softbutton_pressed = true;
282 
283 			continue;
284 		}
285 
286 		/*
287 		 * Bits 4-7 are the touch id, note not all models have
288 		 * hardware touch ids so atm we don't use these.
289 		 */
290 		data->id[touch_nr] = (bufp[SILEAD_POINT_X_MSB_OFF] &
291 				      SILEAD_EXTRA_DATA_MASK) >> 4;
292 		touchscreen_set_mt_pos(&data->pos[touch_nr], &data->prop,
293 			get_unaligned_le16(&bufp[SILEAD_POINT_X_OFF]) & 0xfff,
294 			get_unaligned_le16(&bufp[SILEAD_POINT_Y_OFF]) & 0xfff);
295 		touch_nr++;
296 	}
297 
298 	input_mt_assign_slots(input, data->slots, data->pos, touch_nr, 0);
299 
300 	for (i = 0; i < touch_nr; i++) {
301 		input_mt_slot(input, data->slots[i]);
302 		input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
303 		input_report_abs(input, ABS_MT_POSITION_X, data->pos[i].x);
304 		input_report_abs(input, ABS_MT_POSITION_Y, data->pos[i].y);
305 
306 		dev_dbg(dev, "x=%d y=%d hw_id=%d sw_id=%d\n", data->pos[i].x,
307 			data->pos[i].y, data->id[i], data->slots[i]);
308 	}
309 
310 sync:
311 	input_mt_sync_frame(input);
312 	input_report_key(input, KEY_LEFTMETA, softbutton_pressed);
313 	input_sync(input);
314 }
315 
silead_ts_init(struct i2c_client * client)316 static int silead_ts_init(struct i2c_client *client)
317 {
318 	struct silead_ts_data *data = i2c_get_clientdata(client);
319 	int error;
320 
321 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
322 					  SILEAD_CMD_RESET);
323 	if (error)
324 		goto i2c_write_err;
325 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
326 
327 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_TOUCH_NR,
328 					data->max_fingers);
329 	if (error)
330 		goto i2c_write_err;
331 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
332 
333 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
334 					  SILEAD_CLOCK);
335 	if (error)
336 		goto i2c_write_err;
337 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
338 
339 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
340 					  SILEAD_CMD_START);
341 	if (error)
342 		goto i2c_write_err;
343 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
344 
345 	return 0;
346 
347 i2c_write_err:
348 	dev_err(&client->dev, "Registers clear error %d\n", error);
349 	return error;
350 }
351 
silead_ts_reset(struct i2c_client * client)352 static int silead_ts_reset(struct i2c_client *client)
353 {
354 	int error;
355 
356 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
357 					  SILEAD_CMD_RESET);
358 	if (error)
359 		goto i2c_write_err;
360 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
361 
362 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
363 					  SILEAD_CLOCK);
364 	if (error)
365 		goto i2c_write_err;
366 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
367 
368 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_POWER,
369 					  SILEAD_CMD_START);
370 	if (error)
371 		goto i2c_write_err;
372 	usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
373 
374 	return 0;
375 
376 i2c_write_err:
377 	dev_err(&client->dev, "Chip reset error %d\n", error);
378 	return error;
379 }
380 
silead_ts_startup(struct i2c_client * client)381 static int silead_ts_startup(struct i2c_client *client)
382 {
383 	int error;
384 
385 	error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET, 0x00);
386 	if (error) {
387 		dev_err(&client->dev, "Startup error %d\n", error);
388 		return error;
389 	}
390 
391 	msleep(SILEAD_STARTUP_SLEEP);
392 
393 	return 0;
394 }
395 
silead_ts_load_fw(struct i2c_client * client)396 static int silead_ts_load_fw(struct i2c_client *client)
397 {
398 	struct device *dev = &client->dev;
399 	struct silead_ts_data *data = i2c_get_clientdata(client);
400 	const struct firmware *fw = NULL;
401 	struct silead_fw_data *fw_data;
402 	unsigned int fw_size, i;
403 	int error;
404 
405 	dev_dbg(dev, "Firmware file name: %s", data->fw_name);
406 
407 	/*
408 	 * Unfortunately, at the time of writing this comment, we have been unable to
409 	 * get permission from Silead, or from device OEMs, to distribute the necessary
410 	 * Silead firmware files in linux-firmware.
411 	 *
412 	 * On a whole bunch of devices the UEFI BIOS code contains a touchscreen driver,
413 	 * which contains an embedded copy of the firmware. The fw-loader code has a
414 	 * "platform" fallback mechanism, which together with info on the firmware
415 	 * from drivers/platform/x86/touchscreen_dmi.c will use the firmware from the
416 	 * UEFI driver when the firmware is missing from /lib/firmware. This makes the
417 	 * touchscreen work OOTB without users needing to manually download the firmware.
418 	 *
419 	 * The firmware bundled with the original Windows/Android is usually newer then
420 	 * the firmware in the UEFI driver and it is better calibrated. This better
421 	 * calibration can lead to significant differences in the reported min/max
422 	 * coordinates.
423 	 *
424 	 * To deal with this we first try to load the firmware without "platform"
425 	 * fallback. If that fails we retry with "platform" fallback and if that
426 	 * succeeds we apply an (optional) set of alternative min/max values from the
427 	 * "silead,efi-fw-min-max" property.
428 	 */
429 	error = firmware_request_nowarn(&fw, data->fw_name, dev);
430 	if (error) {
431 		error = firmware_request_platform(&fw, data->fw_name, dev);
432 		if (error) {
433 			dev_err(dev, "Firmware request error %d\n", error);
434 			return error;
435 		}
436 
437 		error = device_property_read_u32_array(dev, "silead,efi-fw-min-max",
438 						       data->efi_fw_min_max,
439 						       ARRAY_SIZE(data->efi_fw_min_max));
440 		if (!error)
441 			data->efi_fw_min_max_set = true;
442 
443 		/* The EFI (platform) embedded fw does not have pen support */
444 		if (data->pen_supported) {
445 			dev_warn(dev, "Warning loading '%s' from filesystem failed, using EFI embedded copy.\n",
446 				 data->fw_name);
447 			dev_warn(dev, "Warning pen support is known to be broken in the EFI embedded fw version\n");
448 			data->pen_supported = false;
449 		}
450 	}
451 
452 	fw_size = fw->size / sizeof(*fw_data);
453 	fw_data = (struct silead_fw_data *)fw->data;
454 
455 	for (i = 0; i < fw_size; i++) {
456 		error = i2c_smbus_write_i2c_block_data(client,
457 						       fw_data[i].offset,
458 						       4,
459 						       (u8 *)&fw_data[i].val);
460 		if (error) {
461 			dev_err(dev, "Firmware load error %d\n", error);
462 			break;
463 		}
464 	}
465 
466 	release_firmware(fw);
467 	return error ?: 0;
468 }
469 
silead_ts_get_status(struct i2c_client * client)470 static u32 silead_ts_get_status(struct i2c_client *client)
471 {
472 	int error;
473 	__le32 status;
474 
475 	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_STATUS,
476 					      sizeof(status), (u8 *)&status);
477 	if (error < 0) {
478 		dev_err(&client->dev, "Status read error %d\n", error);
479 		return error;
480 	}
481 
482 	return le32_to_cpu(status);
483 }
484 
silead_ts_get_id(struct i2c_client * client)485 static int silead_ts_get_id(struct i2c_client *client)
486 {
487 	struct silead_ts_data *data = i2c_get_clientdata(client);
488 	__le32 chip_id;
489 	int error;
490 
491 	error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_ID,
492 					      sizeof(chip_id), (u8 *)&chip_id);
493 	if (error < 0)
494 		return error;
495 
496 	data->chip_id = le32_to_cpu(chip_id);
497 	dev_info(&client->dev, "Silead chip ID: 0x%8X", data->chip_id);
498 
499 	return 0;
500 }
501 
silead_ts_setup(struct i2c_client * client)502 static int silead_ts_setup(struct i2c_client *client)
503 {
504 	int error;
505 	u32 status;
506 
507 	/*
508 	 * Some buggy BIOS-es bring up the chip in a stuck state where it
509 	 * blocks the I2C bus. The following steps are necessary to
510 	 * unstuck the chip / bus:
511 	 * 1. Turn off the Silead chip.
512 	 * 2. Try to do an I2C transfer with the chip, this will fail in
513 	 *    response to which the I2C-bus-driver will call:
514 	 *    i2c_recover_bus() which will unstuck the I2C-bus. Note the
515 	 *    unstuck-ing of the I2C bus only works if we first drop the
516 	 *    chip off the bus by turning it off.
517 	 * 3. Turn the chip back on.
518 	 *
519 	 * On the x86/ACPI systems were this problem is seen, step 1. and
520 	 * 3. require making ACPI calls and dealing with ACPI Power
521 	 * Resources. The workaround below runtime-suspends the chip to
522 	 * turn it off, leaving it up to the ACPI subsystem to deal with
523 	 * this.
524 	 */
525 
526 	if (device_property_read_bool(&client->dev,
527 				      "silead,stuck-controller-bug")) {
528 		pm_runtime_set_active(&client->dev);
529 		pm_runtime_enable(&client->dev);
530 		pm_runtime_allow(&client->dev);
531 
532 		pm_runtime_suspend(&client->dev);
533 
534 		dev_warn(&client->dev, FW_BUG "Stuck I2C bus: please ignore the next 'controller timed out' error\n");
535 		silead_ts_get_id(client);
536 
537 		/* The forbid will also resume the device */
538 		pm_runtime_forbid(&client->dev);
539 		pm_runtime_disable(&client->dev);
540 	}
541 
542 	silead_ts_set_power(client, SILEAD_POWER_OFF);
543 	silead_ts_set_power(client, SILEAD_POWER_ON);
544 
545 	error = silead_ts_get_id(client);
546 	if (error) {
547 		dev_err(&client->dev, "Chip ID read error %d\n", error);
548 		return error;
549 	}
550 
551 	error = silead_ts_init(client);
552 	if (error)
553 		return error;
554 
555 	error = silead_ts_reset(client);
556 	if (error)
557 		return error;
558 
559 	error = silead_ts_load_fw(client);
560 	if (error)
561 		return error;
562 
563 	error = silead_ts_startup(client);
564 	if (error)
565 		return error;
566 
567 	status = silead_ts_get_status(client);
568 	if (status != SILEAD_STATUS_OK) {
569 		dev_err(&client->dev,
570 			"Initialization error, status: 0x%X\n", status);
571 		return -ENODEV;
572 	}
573 
574 	return 0;
575 }
576 
silead_ts_threaded_irq_handler(int irq,void * id)577 static irqreturn_t silead_ts_threaded_irq_handler(int irq, void *id)
578 {
579 	struct silead_ts_data *data = id;
580 	struct i2c_client *client = data->client;
581 
582 	silead_ts_read_data(client);
583 
584 	return IRQ_HANDLED;
585 }
586 
silead_ts_read_props(struct i2c_client * client)587 static void silead_ts_read_props(struct i2c_client *client)
588 {
589 	struct silead_ts_data *data = i2c_get_clientdata(client);
590 	struct device *dev = &client->dev;
591 	const char *str;
592 	int error;
593 
594 	error = device_property_read_u32(dev, "silead,max-fingers",
595 					 &data->max_fingers);
596 	if (error) {
597 		dev_dbg(dev, "Max fingers read error %d\n", error);
598 		data->max_fingers = 5; /* Most devices handle up-to 5 fingers */
599 	}
600 
601 	error = device_property_read_string(dev, "firmware-name", &str);
602 	if (!error)
603 		snprintf(data->fw_name, sizeof(data->fw_name),
604 			 "silead/%s", str);
605 	else
606 		dev_dbg(dev, "Firmware file name read error. Using default.");
607 
608 	data->pen_supported = device_property_read_bool(dev, "silead,pen-supported");
609 	device_property_read_u32(dev, "silead,pen-resolution-x", &data->pen_x_res);
610 	device_property_read_u32(dev, "silead,pen-resolution-y", &data->pen_y_res);
611 }
612 
613 #ifdef CONFIG_ACPI
silead_ts_set_default_fw_name(struct silead_ts_data * data,const struct i2c_device_id * id)614 static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
615 					 const struct i2c_device_id *id)
616 {
617 	const struct acpi_device_id *acpi_id;
618 	struct device *dev = &data->client->dev;
619 	int i;
620 
621 	if (ACPI_HANDLE(dev)) {
622 		acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
623 		if (!acpi_id)
624 			return -ENODEV;
625 
626 		snprintf(data->fw_name, sizeof(data->fw_name),
627 			 "silead/%s.fw", acpi_id->id);
628 
629 		for (i = 0; i < strlen(data->fw_name); i++)
630 			data->fw_name[i] = tolower(data->fw_name[i]);
631 	} else {
632 		snprintf(data->fw_name, sizeof(data->fw_name),
633 			 "silead/%s.fw", id->name);
634 	}
635 
636 	return 0;
637 }
638 #else
silead_ts_set_default_fw_name(struct silead_ts_data * data,const struct i2c_device_id * id)639 static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
640 					 const struct i2c_device_id *id)
641 {
642 	snprintf(data->fw_name, sizeof(data->fw_name),
643 		 "silead/%s.fw", id->name);
644 	return 0;
645 }
646 #endif
647 
silead_disable_regulator(void * arg)648 static void silead_disable_regulator(void *arg)
649 {
650 	struct silead_ts_data *data = arg;
651 
652 	regulator_bulk_disable(ARRAY_SIZE(data->regulators), data->regulators);
653 }
654 
silead_ts_probe(struct i2c_client * client)655 static int silead_ts_probe(struct i2c_client *client)
656 {
657 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
658 	struct silead_ts_data *data;
659 	struct device *dev = &client->dev;
660 	int error;
661 
662 	if (!i2c_check_functionality(client->adapter,
663 				     I2C_FUNC_I2C |
664 				     I2C_FUNC_SMBUS_READ_I2C_BLOCK |
665 				     I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
666 		dev_err(dev, "I2C functionality check failed\n");
667 		return -ENXIO;
668 	}
669 
670 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
671 	if (!data)
672 		return -ENOMEM;
673 
674 	i2c_set_clientdata(client, data);
675 	data->client = client;
676 
677 	error = silead_ts_set_default_fw_name(data, id);
678 	if (error)
679 		return error;
680 
681 	silead_ts_read_props(client);
682 
683 	/* We must have the IRQ provided by DT or ACPI subsystem */
684 	if (client->irq <= 0)
685 		return -ENODEV;
686 
687 	data->regulators[0].supply = "vddio";
688 	data->regulators[1].supply = "avdd";
689 	error = devm_regulator_bulk_get(dev, ARRAY_SIZE(data->regulators),
690 					data->regulators);
691 	if (error)
692 		return error;
693 
694 	/*
695 	 * Enable regulators at probe and disable them at remove, we need
696 	 * to keep the chip powered otherwise it forgets its firmware.
697 	 */
698 	error = regulator_bulk_enable(ARRAY_SIZE(data->regulators),
699 				      data->regulators);
700 	if (error)
701 		return error;
702 
703 	error = devm_add_action_or_reset(dev, silead_disable_regulator, data);
704 	if (error)
705 		return error;
706 
707 	/* Power GPIO pin */
708 	data->gpio_power = devm_gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
709 	if (IS_ERR(data->gpio_power))
710 		return dev_err_probe(dev, PTR_ERR(data->gpio_power),
711 				     "Shutdown GPIO request failed\n");
712 
713 	error = silead_ts_setup(client);
714 	if (error)
715 		return error;
716 
717 	error = silead_ts_request_input_dev(data);
718 	if (error)
719 		return error;
720 
721 	error = silead_ts_request_pen_input_dev(data);
722 	if (error)
723 		return error;
724 
725 	error = devm_request_threaded_irq(dev, client->irq,
726 					  NULL, silead_ts_threaded_irq_handler,
727 					  IRQF_ONESHOT, client->name, data);
728 	if (error) {
729 		if (error != -EPROBE_DEFER)
730 			dev_err(dev, "IRQ request failed %d\n", error);
731 		return error;
732 	}
733 
734 	return 0;
735 }
736 
silead_ts_suspend(struct device * dev)737 static int silead_ts_suspend(struct device *dev)
738 {
739 	struct i2c_client *client = to_i2c_client(dev);
740 
741 	disable_irq(client->irq);
742 	silead_ts_set_power(client, SILEAD_POWER_OFF);
743 	return 0;
744 }
745 
silead_ts_resume(struct device * dev)746 static int silead_ts_resume(struct device *dev)
747 {
748 	struct i2c_client *client = to_i2c_client(dev);
749 	bool second_try = false;
750 	int error, status;
751 
752 	silead_ts_set_power(client, SILEAD_POWER_ON);
753 
754  retry:
755 	error = silead_ts_reset(client);
756 	if (error)
757 		return error;
758 
759 	if (second_try) {
760 		error = silead_ts_load_fw(client);
761 		if (error)
762 			return error;
763 	}
764 
765 	error = silead_ts_startup(client);
766 	if (error)
767 		return error;
768 
769 	status = silead_ts_get_status(client);
770 	if (status != SILEAD_STATUS_OK) {
771 		if (!second_try) {
772 			second_try = true;
773 			dev_dbg(dev, "Reloading firmware after unsuccessful resume\n");
774 			goto retry;
775 		}
776 		dev_err(dev, "Resume error, status: 0x%02x\n", status);
777 		return -ENODEV;
778 	}
779 
780 	enable_irq(client->irq);
781 
782 	return 0;
783 }
784 
785 static DEFINE_SIMPLE_DEV_PM_OPS(silead_ts_pm, silead_ts_suspend, silead_ts_resume);
786 
787 static const struct i2c_device_id silead_ts_id[] = {
788 	{ "gsl1680", 0 },
789 	{ "gsl1688", 0 },
790 	{ "gsl3670", 0 },
791 	{ "gsl3675", 0 },
792 	{ "gsl3692", 0 },
793 	{ "mssl1680", 0 },
794 	{ }
795 };
796 MODULE_DEVICE_TABLE(i2c, silead_ts_id);
797 
798 #ifdef CONFIG_ACPI
799 static const struct acpi_device_id silead_ts_acpi_match[] = {
800 	{ "GSL1680", 0 },
801 	{ "GSL1688", 0 },
802 	{ "GSL3670", 0 },
803 	{ "GSL3675", 0 },
804 	{ "GSL3692", 0 },
805 	{ "MSSL1680", 0 },
806 	{ "MSSL0001", 0 },
807 	{ "MSSL0002", 0 },
808 	{ "MSSL0017", 0 },
809 	{ }
810 };
811 MODULE_DEVICE_TABLE(acpi, silead_ts_acpi_match);
812 #endif
813 
814 #ifdef CONFIG_OF
815 static const struct of_device_id silead_ts_of_match[] = {
816 	{ .compatible = "silead,gsl1680" },
817 	{ .compatible = "silead,gsl1688" },
818 	{ .compatible = "silead,gsl3670" },
819 	{ .compatible = "silead,gsl3675" },
820 	{ .compatible = "silead,gsl3692" },
821 	{ },
822 };
823 MODULE_DEVICE_TABLE(of, silead_ts_of_match);
824 #endif
825 
826 static struct i2c_driver silead_ts_driver = {
827 	.probe = silead_ts_probe,
828 	.id_table = silead_ts_id,
829 	.driver = {
830 		.name = SILEAD_TS_NAME,
831 		.acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
832 		.of_match_table = of_match_ptr(silead_ts_of_match),
833 		.pm = pm_sleep_ptr(&silead_ts_pm),
834 	},
835 };
836 module_i2c_driver(silead_ts_driver);
837 
838 MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
839 MODULE_DESCRIPTION("Silead I2C touchscreen driver");
840 MODULE_LICENSE("GPL");
841