cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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silead.c (22432B)


      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
     61enum silead_ts_power {
     62	SILEAD_POWER_ON  = 1,
     63	SILEAD_POWER_OFF = 0
     64};
     65
     66struct 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
     88struct silead_fw_data {
     89	u32 offset;
     90	u32 val;
     91};
     92
     93static 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
    122static 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
    159static 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
    193static 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
    204static 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
    236sync:
    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
    243static 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
    310sync:
    311	input_mt_sync_frame(input);
    312	input_report_key(input, KEY_LEFTMETA, softbutton_pressed);
    313	input_sync(input);
    314}
    315
    316static 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
    347i2c_write_err:
    348	dev_err(&client->dev, "Registers clear error %d\n", error);
    349	return error;
    350}
    351
    352static 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
    376i2c_write_err:
    377	dev_err(&client->dev, "Chip reset error %d\n", error);
    378	return error;
    379}
    380
    381static 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
    396static 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
    470static 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
    485static 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
    502static 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
    577static 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
    587static 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
    614static 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
    639static 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
    648static 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
    655static int silead_ts_probe(struct i2c_client *client,
    656			   const struct i2c_device_id *id)
    657{
    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		if (PTR_ERR(data->gpio_power) != -EPROBE_DEFER)
    711			dev_err(dev, "Shutdown GPIO request failed\n");
    712		return PTR_ERR(data->gpio_power);
    713	}
    714
    715	error = silead_ts_setup(client);
    716	if (error)
    717		return error;
    718
    719	error = silead_ts_request_input_dev(data);
    720	if (error)
    721		return error;
    722
    723	error = silead_ts_request_pen_input_dev(data);
    724	if (error)
    725		return error;
    726
    727	error = devm_request_threaded_irq(dev, client->irq,
    728					  NULL, silead_ts_threaded_irq_handler,
    729					  IRQF_ONESHOT, client->name, data);
    730	if (error) {
    731		if (error != -EPROBE_DEFER)
    732			dev_err(dev, "IRQ request failed %d\n", error);
    733		return error;
    734	}
    735
    736	return 0;
    737}
    738
    739static int __maybe_unused silead_ts_suspend(struct device *dev)
    740{
    741	struct i2c_client *client = to_i2c_client(dev);
    742
    743	disable_irq(client->irq);
    744	silead_ts_set_power(client, SILEAD_POWER_OFF);
    745	return 0;
    746}
    747
    748static int __maybe_unused silead_ts_resume(struct device *dev)
    749{
    750	struct i2c_client *client = to_i2c_client(dev);
    751	bool second_try = false;
    752	int error, status;
    753
    754	silead_ts_set_power(client, SILEAD_POWER_ON);
    755
    756 retry:
    757	error = silead_ts_reset(client);
    758	if (error)
    759		return error;
    760
    761	if (second_try) {
    762		error = silead_ts_load_fw(client);
    763		if (error)
    764			return error;
    765	}
    766
    767	error = silead_ts_startup(client);
    768	if (error)
    769		return error;
    770
    771	status = silead_ts_get_status(client);
    772	if (status != SILEAD_STATUS_OK) {
    773		if (!second_try) {
    774			second_try = true;
    775			dev_dbg(dev, "Reloading firmware after unsuccessful resume\n");
    776			goto retry;
    777		}
    778		dev_err(dev, "Resume error, status: 0x%02x\n", status);
    779		return -ENODEV;
    780	}
    781
    782	enable_irq(client->irq);
    783
    784	return 0;
    785}
    786
    787static SIMPLE_DEV_PM_OPS(silead_ts_pm, silead_ts_suspend, silead_ts_resume);
    788
    789static const struct i2c_device_id silead_ts_id[] = {
    790	{ "gsl1680", 0 },
    791	{ "gsl1688", 0 },
    792	{ "gsl3670", 0 },
    793	{ "gsl3675", 0 },
    794	{ "gsl3692", 0 },
    795	{ "mssl1680", 0 },
    796	{ }
    797};
    798MODULE_DEVICE_TABLE(i2c, silead_ts_id);
    799
    800#ifdef CONFIG_ACPI
    801static const struct acpi_device_id silead_ts_acpi_match[] = {
    802	{ "GSL1680", 0 },
    803	{ "GSL1688", 0 },
    804	{ "GSL3670", 0 },
    805	{ "GSL3675", 0 },
    806	{ "GSL3692", 0 },
    807	{ "MSSL1680", 0 },
    808	{ "MSSL0001", 0 },
    809	{ "MSSL0002", 0 },
    810	{ "MSSL0017", 0 },
    811	{ }
    812};
    813MODULE_DEVICE_TABLE(acpi, silead_ts_acpi_match);
    814#endif
    815
    816#ifdef CONFIG_OF
    817static const struct of_device_id silead_ts_of_match[] = {
    818	{ .compatible = "silead,gsl1680" },
    819	{ .compatible = "silead,gsl1688" },
    820	{ .compatible = "silead,gsl3670" },
    821	{ .compatible = "silead,gsl3675" },
    822	{ .compatible = "silead,gsl3692" },
    823	{ },
    824};
    825MODULE_DEVICE_TABLE(of, silead_ts_of_match);
    826#endif
    827
    828static struct i2c_driver silead_ts_driver = {
    829	.probe = silead_ts_probe,
    830	.id_table = silead_ts_id,
    831	.driver = {
    832		.name = SILEAD_TS_NAME,
    833		.acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
    834		.of_match_table = of_match_ptr(silead_ts_of_match),
    835		.pm = &silead_ts_pm,
    836	},
    837};
    838module_i2c_driver(silead_ts_driver);
    839
    840MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
    841MODULE_DESCRIPTION("Silead I2C touchscreen driver");
    842MODULE_LICENSE("GPL");