cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
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elants_i2c.c (42619B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * Elan Microelectronics touch panels with I2C interface
      4 *
      5 * Copyright (C) 2014 Elan Microelectronics Corporation.
      6 * Scott Liu <scott.liu@emc.com.tw>
      7 *
      8 * This code is partly based on hid-multitouch.c:
      9 *
     10 *  Copyright (c) 2010-2012 Stephane Chatty <chatty@enac.fr>
     11 *  Copyright (c) 2010-2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
     12 *  Copyright (c) 2010-2012 Ecole Nationale de l'Aviation Civile, France
     13 *
     14 * This code is partly based on i2c-hid.c:
     15 *
     16 * Copyright (c) 2012 Benjamin Tissoires <benjamin.tissoires@gmail.com>
     17 * Copyright (c) 2012 Ecole Nationale de l'Aviation Civile, France
     18 * Copyright (c) 2012 Red Hat, Inc
     19 */
     20
     21
     22#include <linux/bits.h>
     23#include <linux/module.h>
     24#include <linux/input.h>
     25#include <linux/interrupt.h>
     26#include <linux/irq.h>
     27#include <linux/platform_device.h>
     28#include <linux/async.h>
     29#include <linux/i2c.h>
     30#include <linux/delay.h>
     31#include <linux/uaccess.h>
     32#include <linux/buffer_head.h>
     33#include <linux/slab.h>
     34#include <linux/firmware.h>
     35#include <linux/input/mt.h>
     36#include <linux/input/touchscreen.h>
     37#include <linux/acpi.h>
     38#include <linux/of.h>
     39#include <linux/gpio/consumer.h>
     40#include <linux/regulator/consumer.h>
     41#include <linux/uuid.h>
     42#include <asm/unaligned.h>
     43
     44/* Device, Driver information */
     45#define DEVICE_NAME	"elants_i2c"
     46
     47/* Convert from rows or columns into resolution */
     48#define ELAN_TS_RESOLUTION(n, m)   (((n) - 1) * (m))
     49
     50/* FW header data */
     51#define HEADER_SIZE		4
     52#define FW_HDR_TYPE		0
     53#define FW_HDR_COUNT		1
     54#define FW_HDR_LENGTH		2
     55
     56/* Buffer mode Queue Header information */
     57#define QUEUE_HEADER_SINGLE	0x62
     58#define QUEUE_HEADER_NORMAL	0X63
     59#define QUEUE_HEADER_WAIT	0x64
     60#define QUEUE_HEADER_NORMAL2	0x66
     61
     62/* Command header definition */
     63#define CMD_HEADER_WRITE	0x54
     64#define CMD_HEADER_READ		0x53
     65#define CMD_HEADER_6B_READ	0x5B
     66#define CMD_HEADER_ROM_READ	0x96
     67#define CMD_HEADER_RESP		0x52
     68#define CMD_HEADER_6B_RESP	0x9B
     69#define CMD_HEADER_ROM_RESP	0x95
     70#define CMD_HEADER_HELLO	0x55
     71#define CMD_HEADER_REK		0x66
     72
     73/* FW position data */
     74#define PACKET_SIZE_OLD		40
     75#define PACKET_SIZE		55
     76#define MAX_CONTACT_NUM		10
     77#define FW_POS_HEADER		0
     78#define FW_POS_STATE		1
     79#define FW_POS_TOTAL		2
     80#define FW_POS_XY		3
     81#define FW_POS_TOOL_TYPE	33
     82#define FW_POS_CHECKSUM		34
     83#define FW_POS_WIDTH		35
     84#define FW_POS_PRESSURE		45
     85
     86#define HEADER_REPORT_10_FINGER	0x62
     87
     88/* Header (4 bytes) plus 3 full 10-finger packets */
     89#define MAX_PACKET_SIZE		169
     90
     91#define BOOT_TIME_DELAY_MS	50
     92
     93/* FW read command, 0x53 0x?? 0x0, 0x01 */
     94#define E_ELAN_INFO_FW_VER	0x00
     95#define E_ELAN_INFO_BC_VER	0x10
     96#define E_ELAN_INFO_X_RES	0x60
     97#define E_ELAN_INFO_Y_RES	0x63
     98#define E_ELAN_INFO_REK		0xD0
     99#define E_ELAN_INFO_TEST_VER	0xE0
    100#define E_ELAN_INFO_FW_ID	0xF0
    101#define E_INFO_OSR		0xD6
    102#define E_INFO_PHY_SCAN		0xD7
    103#define E_INFO_PHY_DRIVER	0xD8
    104
    105/* FW write command, 0x54 0x?? 0x0, 0x01 */
    106#define E_POWER_STATE_SLEEP	0x50
    107#define E_POWER_STATE_RESUME	0x58
    108
    109#define MAX_RETRIES		3
    110#define MAX_FW_UPDATE_RETRIES	30
    111
    112#define ELAN_FW_PAGESIZE	132
    113
    114/* calibration timeout definition */
    115#define ELAN_CALI_TIMEOUT_MSEC	12000
    116
    117#define ELAN_POWERON_DELAY_USEC	500
    118#define ELAN_RESET_DELAY_MSEC	20
    119
    120/* FW boot code version */
    121#define BC_VER_H_BYTE_FOR_EKTH3900x1_I2C        0x72
    122#define BC_VER_H_BYTE_FOR_EKTH3900x2_I2C        0x82
    123#define BC_VER_H_BYTE_FOR_EKTH3900x3_I2C        0x92
    124#define BC_VER_H_BYTE_FOR_EKTH5312x1_I2C        0x6D
    125#define BC_VER_H_BYTE_FOR_EKTH5312x2_I2C        0x6E
    126#define BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C       0x77
    127#define BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C       0x78
    128#define BC_VER_H_BYTE_FOR_EKTH5312x1_I2C_USB    0x67
    129#define BC_VER_H_BYTE_FOR_EKTH5312x2_I2C_USB    0x68
    130#define BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C_USB   0x74
    131#define BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C_USB   0x75
    132
    133enum elants_chip_id {
    134	EKTH3500,
    135	EKTF3624,
    136};
    137
    138enum elants_state {
    139	ELAN_STATE_NORMAL,
    140	ELAN_WAIT_QUEUE_HEADER,
    141	ELAN_WAIT_RECALIBRATION,
    142};
    143
    144enum elants_iap_mode {
    145	ELAN_IAP_OPERATIONAL,
    146	ELAN_IAP_RECOVERY,
    147};
    148
    149/* struct elants_data - represents state of Elan touchscreen device */
    150struct elants_data {
    151	struct i2c_client *client;
    152	struct input_dev *input;
    153
    154	struct regulator *vcc33;
    155	struct regulator *vccio;
    156	struct gpio_desc *reset_gpio;
    157
    158	u16 fw_version;
    159	u8 test_version;
    160	u8 solution_version;
    161	u8 bc_version;
    162	u8 iap_version;
    163	u16 hw_version;
    164	u8 major_res;
    165	unsigned int x_res;	/* resolution in units/mm */
    166	unsigned int y_res;
    167	unsigned int x_max;
    168	unsigned int y_max;
    169	unsigned int phy_x;
    170	unsigned int phy_y;
    171	struct touchscreen_properties prop;
    172
    173	enum elants_state state;
    174	enum elants_chip_id chip_id;
    175	enum elants_iap_mode iap_mode;
    176
    177	/* Guards against concurrent access to the device via sysfs */
    178	struct mutex sysfs_mutex;
    179
    180	u8 cmd_resp[HEADER_SIZE];
    181	struct completion cmd_done;
    182
    183	bool wake_irq_enabled;
    184	bool keep_power_in_suspend;
    185
    186	/* Must be last to be used for DMA operations */
    187	u8 buf[MAX_PACKET_SIZE] ____cacheline_aligned;
    188};
    189
    190static int elants_i2c_send(struct i2c_client *client,
    191			   const void *data, size_t size)
    192{
    193	int ret;
    194
    195	ret = i2c_master_send(client, data, size);
    196	if (ret == size)
    197		return 0;
    198
    199	if (ret >= 0)
    200		ret = -EIO;
    201
    202	dev_err(&client->dev, "%s failed (%*ph): %d\n",
    203		__func__, (int)size, data, ret);
    204
    205	return ret;
    206}
    207
    208static int elants_i2c_read(struct i2c_client *client, void *data, size_t size)
    209{
    210	int ret;
    211
    212	ret = i2c_master_recv(client, data, size);
    213	if (ret == size)
    214		return 0;
    215
    216	if (ret >= 0)
    217		ret = -EIO;
    218
    219	dev_err(&client->dev, "%s failed: %d\n", __func__, ret);
    220
    221	return ret;
    222}
    223
    224static int elants_i2c_execute_command(struct i2c_client *client,
    225				      const u8 *cmd, size_t cmd_size,
    226				      u8 *resp, size_t resp_size,
    227				      int retries, const char *cmd_name)
    228{
    229	struct i2c_msg msgs[2];
    230	int ret;
    231	u8 expected_response;
    232
    233	switch (cmd[0]) {
    234	case CMD_HEADER_READ:
    235		expected_response = CMD_HEADER_RESP;
    236		break;
    237
    238	case CMD_HEADER_6B_READ:
    239		expected_response = CMD_HEADER_6B_RESP;
    240		break;
    241
    242	case CMD_HEADER_ROM_READ:
    243		expected_response = CMD_HEADER_ROM_RESP;
    244		break;
    245
    246	default:
    247		dev_err(&client->dev, "(%s): invalid command: %*ph\n",
    248			cmd_name, (int)cmd_size, cmd);
    249		return -EINVAL;
    250	}
    251
    252	for (;;) {
    253		msgs[0].addr = client->addr;
    254		msgs[0].flags = client->flags & I2C_M_TEN;
    255		msgs[0].len = cmd_size;
    256		msgs[0].buf = (u8 *)cmd;
    257
    258		msgs[1].addr = client->addr;
    259		msgs[1].flags = (client->flags & I2C_M_TEN) | I2C_M_RD;
    260		msgs[1].flags |= I2C_M_RD;
    261		msgs[1].len = resp_size;
    262		msgs[1].buf = resp;
    263
    264		ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
    265		if (ret < 0) {
    266			if (--retries > 0) {
    267				dev_dbg(&client->dev,
    268					"(%s) I2C transfer failed: %pe (retrying)\n",
    269					cmd_name, ERR_PTR(ret));
    270				continue;
    271			}
    272
    273			dev_err(&client->dev,
    274				"(%s) I2C transfer failed: %pe\n",
    275				cmd_name, ERR_PTR(ret));
    276			return ret;
    277		}
    278
    279		if (ret != ARRAY_SIZE(msgs) ||
    280		    resp[FW_HDR_TYPE] != expected_response) {
    281			if (--retries > 0) {
    282				dev_dbg(&client->dev,
    283					"(%s) unexpected response: %*ph (retrying)\n",
    284					cmd_name, ret, resp);
    285				continue;
    286			}
    287
    288			dev_err(&client->dev,
    289				"(%s) unexpected response: %*ph\n",
    290				cmd_name, ret, resp);
    291			return -EIO;
    292		}
    293
    294		return 0;
    295	}
    296}
    297
    298static int elants_i2c_calibrate(struct elants_data *ts)
    299{
    300	struct i2c_client *client = ts->client;
    301	int ret, error;
    302	static const u8 w_flashkey[] = { CMD_HEADER_WRITE, 0xC0, 0xE1, 0x5A };
    303	static const u8 rek[] = { CMD_HEADER_WRITE, 0x29, 0x00, 0x01 };
    304	static const u8 rek_resp[] = { CMD_HEADER_REK, 0x66, 0x66, 0x66 };
    305
    306	disable_irq(client->irq);
    307
    308	ts->state = ELAN_WAIT_RECALIBRATION;
    309	reinit_completion(&ts->cmd_done);
    310
    311	elants_i2c_send(client, w_flashkey, sizeof(w_flashkey));
    312	elants_i2c_send(client, rek, sizeof(rek));
    313
    314	enable_irq(client->irq);
    315
    316	ret = wait_for_completion_interruptible_timeout(&ts->cmd_done,
    317				msecs_to_jiffies(ELAN_CALI_TIMEOUT_MSEC));
    318
    319	ts->state = ELAN_STATE_NORMAL;
    320
    321	if (ret <= 0) {
    322		error = ret < 0 ? ret : -ETIMEDOUT;
    323		dev_err(&client->dev,
    324			"error while waiting for calibration to complete: %d\n",
    325			error);
    326		return error;
    327	}
    328
    329	if (memcmp(rek_resp, ts->cmd_resp, sizeof(rek_resp))) {
    330		dev_err(&client->dev,
    331			"unexpected calibration response: %*ph\n",
    332			(int)sizeof(ts->cmd_resp), ts->cmd_resp);
    333		return -EINVAL;
    334	}
    335
    336	return 0;
    337}
    338
    339static int elants_i2c_sw_reset(struct i2c_client *client)
    340{
    341	const u8 soft_rst_cmd[] = { 0x77, 0x77, 0x77, 0x77 };
    342	int error;
    343
    344	error = elants_i2c_send(client, soft_rst_cmd,
    345				sizeof(soft_rst_cmd));
    346	if (error) {
    347		dev_err(&client->dev, "software reset failed: %d\n", error);
    348		return error;
    349	}
    350
    351	/*
    352	 * We should wait at least 10 msec (but no more than 40) before
    353	 * sending fastboot or IAP command to the device.
    354	 */
    355	msleep(30);
    356
    357	return 0;
    358}
    359
    360static u16 elants_i2c_parse_version(u8 *buf)
    361{
    362	return get_unaligned_be32(buf) >> 4;
    363}
    364
    365static int elants_i2c_query_hw_version(struct elants_data *ts)
    366{
    367	struct i2c_client *client = ts->client;
    368	int retry_cnt = MAX_RETRIES;
    369	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_ID, 0x00, 0x01 };
    370	u8 resp[HEADER_SIZE];
    371	int error;
    372
    373	while (retry_cnt--) {
    374		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
    375						   resp, sizeof(resp), 1,
    376						   "read fw id");
    377		if (error)
    378			return error;
    379
    380		ts->hw_version = elants_i2c_parse_version(resp);
    381		if (ts->hw_version != 0xffff)
    382			return 0;
    383	}
    384
    385	dev_err(&client->dev, "Invalid fw id: %#04x\n", ts->hw_version);
    386
    387	return -EINVAL;
    388}
    389
    390static int elants_i2c_query_fw_version(struct elants_data *ts)
    391{
    392	struct i2c_client *client = ts->client;
    393	int retry_cnt = MAX_RETRIES;
    394	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_FW_VER, 0x00, 0x01 };
    395	u8 resp[HEADER_SIZE];
    396	int error;
    397
    398	while (retry_cnt--) {
    399		error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
    400						   resp, sizeof(resp), 1,
    401						   "read fw version");
    402		if (error)
    403			return error;
    404
    405		ts->fw_version = elants_i2c_parse_version(resp);
    406		if (ts->fw_version != 0x0000 && ts->fw_version != 0xffff)
    407			return 0;
    408
    409		dev_dbg(&client->dev, "(read fw version) resp %*phC\n",
    410			(int)sizeof(resp), resp);
    411	}
    412
    413	dev_err(&client->dev, "Invalid fw ver: %#04x\n", ts->fw_version);
    414
    415	return -EINVAL;
    416}
    417
    418static int elants_i2c_query_test_version(struct elants_data *ts)
    419{
    420	struct i2c_client *client = ts->client;
    421	int error;
    422	u16 version;
    423	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_TEST_VER, 0x00, 0x01 };
    424	u8 resp[HEADER_SIZE];
    425
    426	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
    427					   resp, sizeof(resp), MAX_RETRIES,
    428					   "read test version");
    429	if (error) {
    430		dev_err(&client->dev, "Failed to read test version\n");
    431		return error;
    432	}
    433
    434	version = elants_i2c_parse_version(resp);
    435	ts->test_version = version >> 8;
    436	ts->solution_version = version & 0xff;
    437
    438	return 0;
    439}
    440
    441static int elants_i2c_query_bc_version(struct elants_data *ts)
    442{
    443	struct i2c_client *client = ts->client;
    444	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_BC_VER, 0x00, 0x01 };
    445	u8 resp[HEADER_SIZE];
    446	u16 version;
    447	int error;
    448
    449	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
    450					   resp, sizeof(resp), 1,
    451					   "read BC version");
    452	if (error)
    453		return error;
    454
    455	version = elants_i2c_parse_version(resp);
    456	ts->bc_version = version >> 8;
    457	ts->iap_version = version & 0xff;
    458
    459	return 0;
    460}
    461
    462static int elants_i2c_query_ts_info_ektf(struct elants_data *ts)
    463{
    464	struct i2c_client *client = ts->client;
    465	int error;
    466	u8 resp[4];
    467	u16 phy_x, phy_y;
    468	const u8 get_xres_cmd[] = {
    469		CMD_HEADER_READ, E_ELAN_INFO_X_RES, 0x00, 0x00
    470	};
    471	const u8 get_yres_cmd[] = {
    472		CMD_HEADER_READ, E_ELAN_INFO_Y_RES, 0x00, 0x00
    473	};
    474
    475	/* Get X/Y size in mm */
    476	error = elants_i2c_execute_command(client, get_xres_cmd,
    477					   sizeof(get_xres_cmd),
    478					   resp, sizeof(resp), 1,
    479					   "get X size");
    480	if (error)
    481		return error;
    482
    483	phy_x = resp[2] | ((resp[3] & 0xF0) << 4);
    484
    485	error = elants_i2c_execute_command(client, get_yres_cmd,
    486					   sizeof(get_yres_cmd),
    487					   resp, sizeof(resp), 1,
    488					   "get Y size");
    489	if (error)
    490		return error;
    491
    492	phy_y = resp[2] | ((resp[3] & 0xF0) << 4);
    493
    494	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
    495
    496	ts->phy_x = phy_x;
    497	ts->phy_y = phy_y;
    498
    499	/* eKTF doesn't report max size, set it to default values */
    500	ts->x_max = 2240 - 1;
    501	ts->y_max = 1408 - 1;
    502
    503	return 0;
    504}
    505
    506static int elants_i2c_query_ts_info_ekth(struct elants_data *ts)
    507{
    508	struct i2c_client *client = ts->client;
    509	int error;
    510	u8 resp[17];
    511	u16 phy_x, phy_y, rows, cols, osr;
    512	const u8 get_resolution_cmd[] = {
    513		CMD_HEADER_6B_READ, 0x00, 0x00, 0x00, 0x00, 0x00
    514	};
    515	const u8 get_osr_cmd[] = {
    516		CMD_HEADER_READ, E_INFO_OSR, 0x00, 0x01
    517	};
    518	const u8 get_physical_scan_cmd[] = {
    519		CMD_HEADER_READ, E_INFO_PHY_SCAN, 0x00, 0x01
    520	};
    521	const u8 get_physical_drive_cmd[] = {
    522		CMD_HEADER_READ, E_INFO_PHY_DRIVER, 0x00, 0x01
    523	};
    524
    525	/* Get trace number */
    526	error = elants_i2c_execute_command(client,
    527					   get_resolution_cmd,
    528					   sizeof(get_resolution_cmd),
    529					   resp, sizeof(resp), 1,
    530					   "get resolution");
    531	if (error)
    532		return error;
    533
    534	rows = resp[2] + resp[6] + resp[10];
    535	cols = resp[3] + resp[7] + resp[11];
    536
    537	/* Get report resolution value of ABS_MT_TOUCH_MAJOR */
    538	ts->major_res = resp[16];
    539
    540	/* Process mm_to_pixel information */
    541	error = elants_i2c_execute_command(client,
    542					   get_osr_cmd, sizeof(get_osr_cmd),
    543					   resp, sizeof(resp), 1, "get osr");
    544	if (error)
    545		return error;
    546
    547	osr = resp[3];
    548
    549	error = elants_i2c_execute_command(client,
    550					   get_physical_scan_cmd,
    551					   sizeof(get_physical_scan_cmd),
    552					   resp, sizeof(resp), 1,
    553					   "get physical scan");
    554	if (error)
    555		return error;
    556
    557	phy_x = get_unaligned_be16(&resp[2]);
    558
    559	error = elants_i2c_execute_command(client,
    560					   get_physical_drive_cmd,
    561					   sizeof(get_physical_drive_cmd),
    562					   resp, sizeof(resp), 1,
    563					   "get physical drive");
    564	if (error)
    565		return error;
    566
    567	phy_y = get_unaligned_be16(&resp[2]);
    568
    569	dev_dbg(&client->dev, "phy_x=%d, phy_y=%d\n", phy_x, phy_y);
    570
    571	if (rows == 0 || cols == 0 || osr == 0) {
    572		dev_warn(&client->dev,
    573			 "invalid trace number data: %d, %d, %d\n",
    574			 rows, cols, osr);
    575	} else {
    576		/* translate trace number to TS resolution */
    577		ts->x_max = ELAN_TS_RESOLUTION(rows, osr);
    578		ts->x_res = DIV_ROUND_CLOSEST(ts->x_max, phy_x);
    579		ts->y_max = ELAN_TS_RESOLUTION(cols, osr);
    580		ts->y_res = DIV_ROUND_CLOSEST(ts->y_max, phy_y);
    581		ts->phy_x = phy_x;
    582		ts->phy_y = phy_y;
    583	}
    584
    585	return 0;
    586}
    587
    588static int elants_i2c_fastboot(struct i2c_client *client)
    589{
    590	const u8 boot_cmd[] = { 0x4D, 0x61, 0x69, 0x6E };
    591	int error;
    592
    593	error = elants_i2c_send(client, boot_cmd, sizeof(boot_cmd));
    594	if (error) {
    595		dev_err(&client->dev, "boot failed: %d\n", error);
    596		return error;
    597	}
    598
    599	dev_dbg(&client->dev, "boot success -- 0x%x\n", client->addr);
    600	return 0;
    601}
    602
    603static int elants_i2c_initialize(struct elants_data *ts)
    604{
    605	struct i2c_client *client = ts->client;
    606	int error, error2, retry_cnt;
    607	const u8 hello_packet[] = { 0x55, 0x55, 0x55, 0x55 };
    608	const u8 recov_packet[] = { 0x55, 0x55, 0x80, 0x80 };
    609	u8 buf[HEADER_SIZE];
    610
    611	for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
    612		error = elants_i2c_sw_reset(client);
    613		if (error) {
    614			/* Continue initializing if it's the last try */
    615			if (retry_cnt < MAX_RETRIES - 1)
    616				continue;
    617		}
    618
    619		error = elants_i2c_fastboot(client);
    620		if (error) {
    621			/* Continue initializing if it's the last try */
    622			if (retry_cnt < MAX_RETRIES - 1)
    623				continue;
    624		}
    625
    626		/* Wait for Hello packet */
    627		msleep(BOOT_TIME_DELAY_MS);
    628
    629		error = elants_i2c_read(client, buf, sizeof(buf));
    630		if (error) {
    631			dev_err(&client->dev,
    632				"failed to read 'hello' packet: %d\n", error);
    633		} else if (!memcmp(buf, hello_packet, sizeof(hello_packet))) {
    634			ts->iap_mode = ELAN_IAP_OPERATIONAL;
    635			break;
    636		} else if (!memcmp(buf, recov_packet, sizeof(recov_packet))) {
    637			/*
    638			 * Setting error code will mark device
    639			 * in recovery mode below.
    640			 */
    641			error = -EIO;
    642			break;
    643		} else {
    644			error = -EINVAL;
    645			dev_err(&client->dev,
    646				"invalid 'hello' packet: %*ph\n",
    647				(int)sizeof(buf), buf);
    648		}
    649	}
    650
    651	/* hw version is available even if device in recovery state */
    652	error2 = elants_i2c_query_hw_version(ts);
    653	if (!error2)
    654		error2 = elants_i2c_query_bc_version(ts);
    655	if (!error)
    656		error = error2;
    657
    658	if (!error)
    659		error = elants_i2c_query_fw_version(ts);
    660	if (!error)
    661		error = elants_i2c_query_test_version(ts);
    662
    663	switch (ts->chip_id) {
    664	case EKTH3500:
    665		if (!error)
    666			error = elants_i2c_query_ts_info_ekth(ts);
    667		break;
    668	case EKTF3624:
    669		if (!error)
    670			error = elants_i2c_query_ts_info_ektf(ts);
    671		break;
    672	default:
    673		BUG();
    674	}
    675
    676	if (error)
    677		ts->iap_mode = ELAN_IAP_RECOVERY;
    678
    679	return 0;
    680}
    681
    682/*
    683 * Firmware update interface.
    684 */
    685
    686static int elants_i2c_fw_write_page(struct i2c_client *client,
    687				    const void *page)
    688{
    689	const u8 ack_ok[] = { 0xaa, 0xaa };
    690	u8 buf[2];
    691	int retry;
    692	int error;
    693
    694	for (retry = 0; retry < MAX_FW_UPDATE_RETRIES; retry++) {
    695		error = elants_i2c_send(client, page, ELAN_FW_PAGESIZE);
    696		if (error) {
    697			dev_err(&client->dev,
    698				"IAP Write Page failed: %d\n", error);
    699			continue;
    700		}
    701
    702		error = elants_i2c_read(client, buf, 2);
    703		if (error) {
    704			dev_err(&client->dev,
    705				"IAP Ack read failed: %d\n", error);
    706			return error;
    707		}
    708
    709		if (!memcmp(buf, ack_ok, sizeof(ack_ok)))
    710			return 0;
    711
    712		error = -EIO;
    713		dev_err(&client->dev,
    714			"IAP Get Ack Error [%02x:%02x]\n",
    715			buf[0], buf[1]);
    716	}
    717
    718	return error;
    719}
    720
    721static int elants_i2c_validate_remark_id(struct elants_data *ts,
    722					 const struct firmware *fw)
    723{
    724	struct i2c_client *client = ts->client;
    725	int error;
    726	const u8 cmd[] = { CMD_HEADER_ROM_READ, 0x80, 0x1F, 0x00, 0x00, 0x21 };
    727	u8 resp[6] = { 0 };
    728	u16 ts_remark_id = 0;
    729	u16 fw_remark_id = 0;
    730
    731	/* Compare TS Remark ID and FW Remark ID */
    732	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
    733					   resp, sizeof(resp),
    734					   1, "read Remark ID");
    735	if (error)
    736		return error;
    737
    738	ts_remark_id = get_unaligned_be16(&resp[3]);
    739
    740	fw_remark_id = get_unaligned_le16(&fw->data[fw->size - 4]);
    741
    742	if (fw_remark_id != ts_remark_id) {
    743		dev_err(&client->dev,
    744			"Remark ID Mismatched: ts_remark_id=0x%04x, fw_remark_id=0x%04x.\n",
    745			ts_remark_id, fw_remark_id);
    746		return -EINVAL;
    747	}
    748
    749	return 0;
    750}
    751
    752static bool elants_i2c_should_check_remark_id(struct elants_data *ts)
    753{
    754	struct i2c_client *client = ts->client;
    755	const u8 bootcode_version = ts->iap_version;
    756	bool check;
    757
    758	/* I2C eKTH3900 and eKTH5312 are NOT support Remark ID */
    759	if ((bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x1_I2C) ||
    760	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x2_I2C) ||
    761	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH3900x3_I2C) ||
    762	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x1_I2C) ||
    763	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x2_I2C) ||
    764	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C) ||
    765	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C) ||
    766	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x1_I2C_USB) ||
    767	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312x2_I2C_USB) ||
    768	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx1_I2C_USB) ||
    769	    (bootcode_version == BC_VER_H_BYTE_FOR_EKTH5312cx2_I2C_USB)) {
    770		dev_dbg(&client->dev,
    771			"eKTH3900/eKTH5312(0x%02x) are not support remark id\n",
    772			bootcode_version);
    773		check = false;
    774	} else if (bootcode_version >= 0x60) {
    775		check = true;
    776	} else {
    777		check = false;
    778	}
    779
    780	return check;
    781}
    782
    783static int elants_i2c_do_update_firmware(struct i2c_client *client,
    784					 const struct firmware *fw,
    785					 bool force)
    786{
    787	struct elants_data *ts = i2c_get_clientdata(client);
    788	const u8 enter_iap[] = { 0x45, 0x49, 0x41, 0x50 };
    789	const u8 enter_iap2[] = { 0x54, 0x00, 0x12, 0x34 };
    790	const u8 iap_ack[] = { 0x55, 0xaa, 0x33, 0xcc };
    791	const u8 close_idle[] = { 0x54, 0x2c, 0x01, 0x01 };
    792	u8 buf[HEADER_SIZE];
    793	u16 send_id;
    794	int page, n_fw_pages;
    795	int error;
    796	bool check_remark_id = elants_i2c_should_check_remark_id(ts);
    797
    798	/* Recovery mode detection! */
    799	if (force) {
    800		dev_dbg(&client->dev, "Recovery mode procedure\n");
    801
    802		if (check_remark_id) {
    803			error = elants_i2c_validate_remark_id(ts, fw);
    804			if (error)
    805				return error;
    806		}
    807
    808		error = elants_i2c_send(client, enter_iap2, sizeof(enter_iap2));
    809		if (error) {
    810			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
    811				error);
    812			return error;
    813		}
    814	} else {
    815		/* Start IAP Procedure */
    816		dev_dbg(&client->dev, "Normal IAP procedure\n");
    817
    818		/* Close idle mode */
    819		error = elants_i2c_send(client, close_idle, sizeof(close_idle));
    820		if (error)
    821			dev_err(&client->dev, "Failed close idle: %d\n", error);
    822		msleep(60);
    823
    824		elants_i2c_sw_reset(client);
    825		msleep(20);
    826
    827		if (check_remark_id) {
    828			error = elants_i2c_validate_remark_id(ts, fw);
    829			if (error)
    830				return error;
    831		}
    832
    833		error = elants_i2c_send(client, enter_iap, sizeof(enter_iap));
    834		if (error) {
    835			dev_err(&client->dev, "failed to enter IAP mode: %d\n",
    836				error);
    837			return error;
    838		}
    839	}
    840
    841	msleep(20);
    842
    843	/* check IAP state */
    844	error = elants_i2c_read(client, buf, 4);
    845	if (error) {
    846		dev_err(&client->dev,
    847			"failed to read IAP acknowledgement: %d\n",
    848			error);
    849		return error;
    850	}
    851
    852	if (memcmp(buf, iap_ack, sizeof(iap_ack))) {
    853		dev_err(&client->dev,
    854			"failed to enter IAP: %*ph (expected %*ph)\n",
    855			(int)sizeof(buf), buf, (int)sizeof(iap_ack), iap_ack);
    856		return -EIO;
    857	}
    858
    859	dev_info(&client->dev, "successfully entered IAP mode");
    860
    861	send_id = client->addr;
    862	error = elants_i2c_send(client, &send_id, 1);
    863	if (error) {
    864		dev_err(&client->dev, "sending dummy byte failed: %d\n",
    865			error);
    866		return error;
    867	}
    868
    869	/* Clear the last page of Master */
    870	error = elants_i2c_send(client, fw->data, ELAN_FW_PAGESIZE);
    871	if (error) {
    872		dev_err(&client->dev, "clearing of the last page failed: %d\n",
    873			error);
    874		return error;
    875	}
    876
    877	error = elants_i2c_read(client, buf, 2);
    878	if (error) {
    879		dev_err(&client->dev,
    880			"failed to read ACK for clearing the last page: %d\n",
    881			error);
    882		return error;
    883	}
    884
    885	n_fw_pages = fw->size / ELAN_FW_PAGESIZE;
    886	dev_dbg(&client->dev, "IAP Pages = %d\n", n_fw_pages);
    887
    888	for (page = 0; page < n_fw_pages; page++) {
    889		error = elants_i2c_fw_write_page(client,
    890					fw->data + page * ELAN_FW_PAGESIZE);
    891		if (error) {
    892			dev_err(&client->dev,
    893				"failed to write FW page %d: %d\n",
    894				page, error);
    895			return error;
    896		}
    897	}
    898
    899	/* Old iap needs to wait 200ms for WDT and rest is for hello packets */
    900	msleep(300);
    901
    902	dev_info(&client->dev, "firmware update completed\n");
    903	return 0;
    904}
    905
    906static int elants_i2c_fw_update(struct elants_data *ts)
    907{
    908	struct i2c_client *client = ts->client;
    909	const struct firmware *fw;
    910	char *fw_name;
    911	int error;
    912
    913	fw_name = kasprintf(GFP_KERNEL, "elants_i2c_%04x.bin", ts->hw_version);
    914	if (!fw_name)
    915		return -ENOMEM;
    916
    917	dev_info(&client->dev, "requesting fw name = %s\n", fw_name);
    918	error = request_firmware(&fw, fw_name, &client->dev);
    919	kfree(fw_name);
    920	if (error) {
    921		dev_err(&client->dev, "failed to request firmware: %d\n",
    922			error);
    923		return error;
    924	}
    925
    926	if (fw->size % ELAN_FW_PAGESIZE) {
    927		dev_err(&client->dev, "invalid firmware length: %zu\n",
    928			fw->size);
    929		error = -EINVAL;
    930		goto out;
    931	}
    932
    933	disable_irq(client->irq);
    934
    935	error = elants_i2c_do_update_firmware(client, fw,
    936					ts->iap_mode == ELAN_IAP_RECOVERY);
    937	if (error) {
    938		dev_err(&client->dev, "firmware update failed: %d\n", error);
    939		ts->iap_mode = ELAN_IAP_RECOVERY;
    940		goto out_enable_irq;
    941	}
    942
    943	error = elants_i2c_initialize(ts);
    944	if (error) {
    945		dev_err(&client->dev,
    946			"failed to initialize device after firmware update: %d\n",
    947			error);
    948		ts->iap_mode = ELAN_IAP_RECOVERY;
    949		goto out_enable_irq;
    950	}
    951
    952	ts->iap_mode = ELAN_IAP_OPERATIONAL;
    953
    954out_enable_irq:
    955	ts->state = ELAN_STATE_NORMAL;
    956	enable_irq(client->irq);
    957	msleep(100);
    958
    959	if (!error)
    960		elants_i2c_calibrate(ts);
    961out:
    962	release_firmware(fw);
    963	return error;
    964}
    965
    966/*
    967 * Event reporting.
    968 */
    969
    970static void elants_i2c_mt_event(struct elants_data *ts, u8 *buf,
    971				size_t packet_size)
    972{
    973	struct input_dev *input = ts->input;
    974	unsigned int n_fingers;
    975	unsigned int tool_type;
    976	u16 finger_state;
    977	int i;
    978
    979	n_fingers = buf[FW_POS_STATE + 1] & 0x0f;
    980	finger_state = ((buf[FW_POS_STATE + 1] & 0x30) << 4) |
    981			buf[FW_POS_STATE];
    982
    983	dev_dbg(&ts->client->dev,
    984		"n_fingers: %u, state: %04x\n",  n_fingers, finger_state);
    985
    986	/* Note: all fingers have the same tool type */
    987	tool_type = buf[FW_POS_TOOL_TYPE] & BIT(0) ?
    988			MT_TOOL_FINGER : MT_TOOL_PALM;
    989
    990	for (i = 0; i < MAX_CONTACT_NUM && n_fingers; i++) {
    991		if (finger_state & 1) {
    992			unsigned int x, y, p, w;
    993			u8 *pos;
    994
    995			pos = &buf[FW_POS_XY + i * 3];
    996			x = (((u16)pos[0] & 0xf0) << 4) | pos[1];
    997			y = (((u16)pos[0] & 0x0f) << 8) | pos[2];
    998
    999			/*
   1000			 * eKTF3624 may have use "old" touch-report format,
   1001			 * depending on a device and TS firmware version.
   1002			 * For example, ASUS Transformer devices use the "old"
   1003			 * format, while ASUS Nexus 7 uses the "new" formant.
   1004			 */
   1005			if (packet_size == PACKET_SIZE_OLD &&
   1006			    ts->chip_id == EKTF3624) {
   1007				w = buf[FW_POS_WIDTH + i / 2];
   1008				w >>= 4 * (~i & 1);
   1009				w |= w << 4;
   1010				w |= !w;
   1011				p = w;
   1012			} else {
   1013				p = buf[FW_POS_PRESSURE + i];
   1014				w = buf[FW_POS_WIDTH + i];
   1015			}
   1016
   1017			dev_dbg(&ts->client->dev, "i=%d x=%d y=%d p=%d w=%d\n",
   1018				i, x, y, p, w);
   1019
   1020			input_mt_slot(input, i);
   1021			input_mt_report_slot_state(input, tool_type, true);
   1022			touchscreen_report_pos(input, &ts->prop, x, y, true);
   1023			input_event(input, EV_ABS, ABS_MT_PRESSURE, p);
   1024			input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, w);
   1025
   1026			n_fingers--;
   1027		}
   1028
   1029		finger_state >>= 1;
   1030	}
   1031
   1032	input_mt_sync_frame(input);
   1033	input_sync(input);
   1034}
   1035
   1036static u8 elants_i2c_calculate_checksum(u8 *buf)
   1037{
   1038	u8 checksum = 0;
   1039	u8 i;
   1040
   1041	for (i = 0; i < FW_POS_CHECKSUM; i++)
   1042		checksum += buf[i];
   1043
   1044	return checksum;
   1045}
   1046
   1047static void elants_i2c_event(struct elants_data *ts, u8 *buf,
   1048			     size_t packet_size)
   1049{
   1050	u8 checksum = elants_i2c_calculate_checksum(buf);
   1051
   1052	if (unlikely(buf[FW_POS_CHECKSUM] != checksum))
   1053		dev_warn(&ts->client->dev,
   1054			 "%s: invalid checksum for packet %02x: %02x vs. %02x\n",
   1055			 __func__, buf[FW_POS_HEADER],
   1056			 checksum, buf[FW_POS_CHECKSUM]);
   1057	else if (unlikely(buf[FW_POS_HEADER] != HEADER_REPORT_10_FINGER))
   1058		dev_warn(&ts->client->dev,
   1059			 "%s: unknown packet type: %02x\n",
   1060			 __func__, buf[FW_POS_HEADER]);
   1061	else
   1062		elants_i2c_mt_event(ts, buf, packet_size);
   1063}
   1064
   1065static irqreturn_t elants_i2c_irq(int irq, void *_dev)
   1066{
   1067	const u8 wait_packet[] = { 0x64, 0x64, 0x64, 0x64 };
   1068	struct elants_data *ts = _dev;
   1069	struct i2c_client *client = ts->client;
   1070	int report_count, report_len;
   1071	int i;
   1072	int len;
   1073
   1074	len = i2c_master_recv_dmasafe(client, ts->buf, sizeof(ts->buf));
   1075	if (len < 0) {
   1076		dev_err(&client->dev, "%s: failed to read data: %d\n",
   1077			__func__, len);
   1078		goto out;
   1079	}
   1080
   1081	dev_dbg(&client->dev, "%s: packet %*ph\n",
   1082		__func__, HEADER_SIZE, ts->buf);
   1083
   1084	switch (ts->state) {
   1085	case ELAN_WAIT_RECALIBRATION:
   1086		if (ts->buf[FW_HDR_TYPE] == CMD_HEADER_REK) {
   1087			memcpy(ts->cmd_resp, ts->buf, sizeof(ts->cmd_resp));
   1088			complete(&ts->cmd_done);
   1089			ts->state = ELAN_STATE_NORMAL;
   1090		}
   1091		break;
   1092
   1093	case ELAN_WAIT_QUEUE_HEADER:
   1094		if (ts->buf[FW_HDR_TYPE] != QUEUE_HEADER_NORMAL)
   1095			break;
   1096
   1097		ts->state = ELAN_STATE_NORMAL;
   1098		fallthrough;
   1099
   1100	case ELAN_STATE_NORMAL:
   1101
   1102		switch (ts->buf[FW_HDR_TYPE]) {
   1103		case CMD_HEADER_HELLO:
   1104		case CMD_HEADER_RESP:
   1105			break;
   1106
   1107		case QUEUE_HEADER_WAIT:
   1108			if (memcmp(ts->buf, wait_packet, sizeof(wait_packet))) {
   1109				dev_err(&client->dev,
   1110					"invalid wait packet %*ph\n",
   1111					HEADER_SIZE, ts->buf);
   1112			} else {
   1113				ts->state = ELAN_WAIT_QUEUE_HEADER;
   1114				udelay(30);
   1115			}
   1116			break;
   1117
   1118		case QUEUE_HEADER_SINGLE:
   1119			elants_i2c_event(ts, &ts->buf[HEADER_SIZE],
   1120					 ts->buf[FW_HDR_LENGTH]);
   1121			break;
   1122
   1123		case QUEUE_HEADER_NORMAL2: /* CMD_HEADER_REK */
   1124			/*
   1125			 * Depending on firmware version, eKTF3624 touchscreens
   1126			 * may utilize one of these opcodes for the touch events:
   1127			 * 0x63 (NORMAL) and 0x66 (NORMAL2).  The 0x63 is used by
   1128			 * older firmware version and differs from 0x66 such that
   1129			 * touch pressure value needs to be adjusted.  The 0x66
   1130			 * opcode of newer firmware is equal to 0x63 of eKTH3500.
   1131			 */
   1132			if (ts->chip_id != EKTF3624)
   1133				break;
   1134
   1135			fallthrough;
   1136
   1137		case QUEUE_HEADER_NORMAL:
   1138			report_count = ts->buf[FW_HDR_COUNT];
   1139			if (report_count == 0 || report_count > 3) {
   1140				dev_err(&client->dev,
   1141					"bad report count: %*ph\n",
   1142					HEADER_SIZE, ts->buf);
   1143				break;
   1144			}
   1145
   1146			report_len = ts->buf[FW_HDR_LENGTH] / report_count;
   1147
   1148			if (report_len == PACKET_SIZE_OLD &&
   1149			    ts->chip_id == EKTF3624) {
   1150				dev_dbg_once(&client->dev,
   1151					     "using old report format\n");
   1152			} else if (report_len != PACKET_SIZE) {
   1153				dev_err(&client->dev,
   1154					"mismatching report length: %*ph\n",
   1155					HEADER_SIZE, ts->buf);
   1156				break;
   1157			}
   1158
   1159			for (i = 0; i < report_count; i++) {
   1160				u8 *buf = ts->buf + HEADER_SIZE +
   1161							i * report_len;
   1162				elants_i2c_event(ts, buf, report_len);
   1163			}
   1164			break;
   1165
   1166		default:
   1167			dev_err(&client->dev, "unknown packet %*ph\n",
   1168				HEADER_SIZE, ts->buf);
   1169			break;
   1170		}
   1171		break;
   1172	}
   1173
   1174out:
   1175	return IRQ_HANDLED;
   1176}
   1177
   1178/*
   1179 * sysfs interface
   1180 */
   1181static ssize_t calibrate_store(struct device *dev,
   1182			       struct device_attribute *attr,
   1183			       const char *buf, size_t count)
   1184{
   1185	struct i2c_client *client = to_i2c_client(dev);
   1186	struct elants_data *ts = i2c_get_clientdata(client);
   1187	int error;
   1188
   1189	error = mutex_lock_interruptible(&ts->sysfs_mutex);
   1190	if (error)
   1191		return error;
   1192
   1193	error = elants_i2c_calibrate(ts);
   1194
   1195	mutex_unlock(&ts->sysfs_mutex);
   1196	return error ?: count;
   1197}
   1198
   1199static ssize_t write_update_fw(struct device *dev,
   1200			       struct device_attribute *attr,
   1201			       const char *buf, size_t count)
   1202{
   1203	struct i2c_client *client = to_i2c_client(dev);
   1204	struct elants_data *ts = i2c_get_clientdata(client);
   1205	int error;
   1206
   1207	error = mutex_lock_interruptible(&ts->sysfs_mutex);
   1208	if (error)
   1209		return error;
   1210
   1211	error = elants_i2c_fw_update(ts);
   1212	dev_dbg(dev, "firmware update result: %d\n", error);
   1213
   1214	mutex_unlock(&ts->sysfs_mutex);
   1215	return error ?: count;
   1216}
   1217
   1218static ssize_t show_iap_mode(struct device *dev,
   1219			     struct device_attribute *attr, char *buf)
   1220{
   1221	struct i2c_client *client = to_i2c_client(dev);
   1222	struct elants_data *ts = i2c_get_clientdata(client);
   1223
   1224	return sprintf(buf, "%s\n",
   1225		       ts->iap_mode == ELAN_IAP_OPERATIONAL ?
   1226				"Normal" : "Recovery");
   1227}
   1228
   1229static ssize_t show_calibration_count(struct device *dev,
   1230				      struct device_attribute *attr, char *buf)
   1231{
   1232	struct i2c_client *client = to_i2c_client(dev);
   1233	const u8 cmd[] = { CMD_HEADER_READ, E_ELAN_INFO_REK, 0x00, 0x01 };
   1234	u8 resp[HEADER_SIZE];
   1235	u16 rek_count;
   1236	int error;
   1237
   1238	error = elants_i2c_execute_command(client, cmd, sizeof(cmd),
   1239					   resp, sizeof(resp), 1,
   1240					   "read ReK status");
   1241	if (error)
   1242		return sprintf(buf, "%d\n", error);
   1243
   1244	rek_count = get_unaligned_be16(&resp[2]);
   1245	return sprintf(buf, "0x%04x\n", rek_count);
   1246}
   1247
   1248static DEVICE_ATTR_WO(calibrate);
   1249static DEVICE_ATTR(iap_mode, S_IRUGO, show_iap_mode, NULL);
   1250static DEVICE_ATTR(calibration_count, S_IRUGO, show_calibration_count, NULL);
   1251static DEVICE_ATTR(update_fw, S_IWUSR, NULL, write_update_fw);
   1252
   1253struct elants_version_attribute {
   1254	struct device_attribute dattr;
   1255	size_t field_offset;
   1256	size_t field_size;
   1257};
   1258
   1259#define __ELANTS_FIELD_SIZE(_field)					\
   1260	sizeof(((struct elants_data *)NULL)->_field)
   1261#define __ELANTS_VERIFY_SIZE(_field)					\
   1262	(BUILD_BUG_ON_ZERO(__ELANTS_FIELD_SIZE(_field) > 2) +		\
   1263	 __ELANTS_FIELD_SIZE(_field))
   1264#define ELANTS_VERSION_ATTR(_field)					\
   1265	struct elants_version_attribute elants_ver_attr_##_field = {	\
   1266		.dattr = __ATTR(_field, S_IRUGO,			\
   1267				elants_version_attribute_show, NULL),	\
   1268		.field_offset = offsetof(struct elants_data, _field),	\
   1269		.field_size = __ELANTS_VERIFY_SIZE(_field),		\
   1270	}
   1271
   1272static ssize_t elants_version_attribute_show(struct device *dev,
   1273					     struct device_attribute *dattr,
   1274					     char *buf)
   1275{
   1276	struct i2c_client *client = to_i2c_client(dev);
   1277	struct elants_data *ts = i2c_get_clientdata(client);
   1278	struct elants_version_attribute *attr =
   1279		container_of(dattr, struct elants_version_attribute, dattr);
   1280	u8 *field = (u8 *)((char *)ts + attr->field_offset);
   1281	unsigned int fmt_size;
   1282	unsigned int val;
   1283
   1284	if (attr->field_size == 1) {
   1285		val = *field;
   1286		fmt_size = 2; /* 2 HEX digits */
   1287	} else {
   1288		val = *(u16 *)field;
   1289		fmt_size = 4; /* 4 HEX digits */
   1290	}
   1291
   1292	return sprintf(buf, "%0*x\n", fmt_size, val);
   1293}
   1294
   1295static ELANTS_VERSION_ATTR(fw_version);
   1296static ELANTS_VERSION_ATTR(hw_version);
   1297static ELANTS_VERSION_ATTR(test_version);
   1298static ELANTS_VERSION_ATTR(solution_version);
   1299static ELANTS_VERSION_ATTR(bc_version);
   1300static ELANTS_VERSION_ATTR(iap_version);
   1301
   1302static struct attribute *elants_attributes[] = {
   1303	&dev_attr_calibrate.attr,
   1304	&dev_attr_update_fw.attr,
   1305	&dev_attr_iap_mode.attr,
   1306	&dev_attr_calibration_count.attr,
   1307
   1308	&elants_ver_attr_fw_version.dattr.attr,
   1309	&elants_ver_attr_hw_version.dattr.attr,
   1310	&elants_ver_attr_test_version.dattr.attr,
   1311	&elants_ver_attr_solution_version.dattr.attr,
   1312	&elants_ver_attr_bc_version.dattr.attr,
   1313	&elants_ver_attr_iap_version.dattr.attr,
   1314	NULL
   1315};
   1316
   1317static const struct attribute_group elants_attribute_group = {
   1318	.attrs = elants_attributes,
   1319};
   1320
   1321static int elants_i2c_power_on(struct elants_data *ts)
   1322{
   1323	int error;
   1324
   1325	/*
   1326	 * If we do not have reset gpio assume platform firmware
   1327	 * controls regulators and does power them on for us.
   1328	 */
   1329	if (IS_ERR_OR_NULL(ts->reset_gpio))
   1330		return 0;
   1331
   1332	gpiod_set_value_cansleep(ts->reset_gpio, 1);
   1333
   1334	error = regulator_enable(ts->vcc33);
   1335	if (error) {
   1336		dev_err(&ts->client->dev,
   1337			"failed to enable vcc33 regulator: %d\n",
   1338			error);
   1339		goto release_reset_gpio;
   1340	}
   1341
   1342	error = regulator_enable(ts->vccio);
   1343	if (error) {
   1344		dev_err(&ts->client->dev,
   1345			"failed to enable vccio regulator: %d\n",
   1346			error);
   1347		regulator_disable(ts->vcc33);
   1348		goto release_reset_gpio;
   1349	}
   1350
   1351	/*
   1352	 * We need to wait a bit after powering on controller before
   1353	 * we are allowed to release reset GPIO.
   1354	 */
   1355	udelay(ELAN_POWERON_DELAY_USEC);
   1356
   1357release_reset_gpio:
   1358	gpiod_set_value_cansleep(ts->reset_gpio, 0);
   1359	if (error)
   1360		return error;
   1361
   1362	msleep(ELAN_RESET_DELAY_MSEC);
   1363
   1364	return 0;
   1365}
   1366
   1367static void elants_i2c_power_off(void *_data)
   1368{
   1369	struct elants_data *ts = _data;
   1370
   1371	if (!IS_ERR_OR_NULL(ts->reset_gpio)) {
   1372		/*
   1373		 * Activate reset gpio to prevent leakage through the
   1374		 * pin once we shut off power to the controller.
   1375		 */
   1376		gpiod_set_value_cansleep(ts->reset_gpio, 1);
   1377		regulator_disable(ts->vccio);
   1378		regulator_disable(ts->vcc33);
   1379	}
   1380}
   1381
   1382#ifdef CONFIG_ACPI
   1383static const struct acpi_device_id i2c_hid_ids[] = {
   1384	{"ACPI0C50", 0 },
   1385	{"PNP0C50", 0 },
   1386	{ },
   1387};
   1388
   1389static const guid_t i2c_hid_guid =
   1390	GUID_INIT(0x3CDFF6F7, 0x4267, 0x4555,
   1391		  0xAD, 0x05, 0xB3, 0x0A, 0x3D, 0x89, 0x38, 0xDE);
   1392
   1393static bool elants_acpi_is_hid_device(struct device *dev)
   1394{
   1395	acpi_handle handle = ACPI_HANDLE(dev);
   1396	union acpi_object *obj;
   1397
   1398	if (acpi_match_device_ids(ACPI_COMPANION(dev), i2c_hid_ids))
   1399		return false;
   1400
   1401	obj = acpi_evaluate_dsm_typed(handle, &i2c_hid_guid, 1, 1, NULL, ACPI_TYPE_INTEGER);
   1402	if (obj) {
   1403		ACPI_FREE(obj);
   1404		return true;
   1405	}
   1406
   1407	return false;
   1408}
   1409#else
   1410static bool elants_acpi_is_hid_device(struct device *dev)
   1411{
   1412	return false;
   1413}
   1414#endif
   1415
   1416static int elants_i2c_probe(struct i2c_client *client)
   1417{
   1418	union i2c_smbus_data dummy;
   1419	struct elants_data *ts;
   1420	unsigned long irqflags;
   1421	int error;
   1422
   1423	/* Don't bind to i2c-hid compatible devices, these are handled by the i2c-hid drv. */
   1424	if (elants_acpi_is_hid_device(&client->dev)) {
   1425		dev_warn(&client->dev, "This device appears to be an I2C-HID device, not binding\n");
   1426		return -ENODEV;
   1427	}
   1428
   1429	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
   1430		dev_err(&client->dev, "I2C check functionality error\n");
   1431		return -ENXIO;
   1432	}
   1433
   1434	ts = devm_kzalloc(&client->dev, sizeof(struct elants_data), GFP_KERNEL);
   1435	if (!ts)
   1436		return -ENOMEM;
   1437
   1438	mutex_init(&ts->sysfs_mutex);
   1439	init_completion(&ts->cmd_done);
   1440
   1441	ts->client = client;
   1442	ts->chip_id = (enum elants_chip_id)(uintptr_t)device_get_match_data(&client->dev);
   1443	i2c_set_clientdata(client, ts);
   1444
   1445	ts->vcc33 = devm_regulator_get(&client->dev, "vcc33");
   1446	if (IS_ERR(ts->vcc33)) {
   1447		error = PTR_ERR(ts->vcc33);
   1448		if (error != -EPROBE_DEFER)
   1449			dev_err(&client->dev,
   1450				"Failed to get 'vcc33' regulator: %d\n",
   1451				error);
   1452		return error;
   1453	}
   1454
   1455	ts->vccio = devm_regulator_get(&client->dev, "vccio");
   1456	if (IS_ERR(ts->vccio)) {
   1457		error = PTR_ERR(ts->vccio);
   1458		if (error != -EPROBE_DEFER)
   1459			dev_err(&client->dev,
   1460				"Failed to get 'vccio' regulator: %d\n",
   1461				error);
   1462		return error;
   1463	}
   1464
   1465	ts->reset_gpio = devm_gpiod_get(&client->dev, "reset", GPIOD_OUT_LOW);
   1466	if (IS_ERR(ts->reset_gpio)) {
   1467		error = PTR_ERR(ts->reset_gpio);
   1468
   1469		if (error == -EPROBE_DEFER)
   1470			return error;
   1471
   1472		if (error != -ENOENT && error != -ENOSYS) {
   1473			dev_err(&client->dev,
   1474				"failed to get reset gpio: %d\n",
   1475				error);
   1476			return error;
   1477		}
   1478
   1479		ts->keep_power_in_suspend = true;
   1480	}
   1481
   1482	error = elants_i2c_power_on(ts);
   1483	if (error)
   1484		return error;
   1485
   1486	error = devm_add_action_or_reset(&client->dev,
   1487					 elants_i2c_power_off, ts);
   1488	if (error) {
   1489		dev_err(&client->dev,
   1490			"failed to install power off action: %d\n", error);
   1491		return error;
   1492	}
   1493
   1494	/* Make sure there is something at this address */
   1495	if (i2c_smbus_xfer(client->adapter, client->addr, 0,
   1496			   I2C_SMBUS_READ, 0, I2C_SMBUS_BYTE, &dummy) < 0) {
   1497		dev_err(&client->dev, "nothing at this address\n");
   1498		return -ENXIO;
   1499	}
   1500
   1501	error = elants_i2c_initialize(ts);
   1502	if (error) {
   1503		dev_err(&client->dev, "failed to initialize: %d\n", error);
   1504		return error;
   1505	}
   1506
   1507	ts->input = devm_input_allocate_device(&client->dev);
   1508	if (!ts->input) {
   1509		dev_err(&client->dev, "Failed to allocate input device\n");
   1510		return -ENOMEM;
   1511	}
   1512
   1513	ts->input->name = "Elan Touchscreen";
   1514	ts->input->id.bustype = BUS_I2C;
   1515
   1516	/* Multitouch input params setup */
   1517
   1518	input_set_abs_params(ts->input, ABS_MT_POSITION_X, 0, ts->x_max, 0, 0);
   1519	input_set_abs_params(ts->input, ABS_MT_POSITION_Y, 0, ts->y_max, 0, 0);
   1520	input_set_abs_params(ts->input, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
   1521	input_set_abs_params(ts->input, ABS_MT_PRESSURE, 0, 255, 0, 0);
   1522	input_set_abs_params(ts->input, ABS_MT_TOOL_TYPE,
   1523			     0, MT_TOOL_PALM, 0, 0);
   1524
   1525	touchscreen_parse_properties(ts->input, true, &ts->prop);
   1526
   1527	if (ts->chip_id == EKTF3624 && ts->phy_x && ts->phy_y) {
   1528		/* calculate resolution from size */
   1529		ts->x_res = DIV_ROUND_CLOSEST(ts->prop.max_x, ts->phy_x);
   1530		ts->y_res = DIV_ROUND_CLOSEST(ts->prop.max_y, ts->phy_y);
   1531	}
   1532
   1533	input_abs_set_res(ts->input, ABS_MT_POSITION_X, ts->x_res);
   1534	input_abs_set_res(ts->input, ABS_MT_POSITION_Y, ts->y_res);
   1535	input_abs_set_res(ts->input, ABS_MT_TOUCH_MAJOR, ts->major_res);
   1536
   1537	error = input_mt_init_slots(ts->input, MAX_CONTACT_NUM,
   1538				    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
   1539	if (error) {
   1540		dev_err(&client->dev,
   1541			"failed to initialize MT slots: %d\n", error);
   1542		return error;
   1543	}
   1544
   1545	error = input_register_device(ts->input);
   1546	if (error) {
   1547		dev_err(&client->dev,
   1548			"unable to register input device: %d\n", error);
   1549		return error;
   1550	}
   1551
   1552	/*
   1553	 * Platform code (ACPI, DTS) should normally set up interrupt
   1554	 * for us, but in case it did not let's fall back to using falling
   1555	 * edge to be compatible with older Chromebooks.
   1556	 */
   1557	irqflags = irq_get_trigger_type(client->irq);
   1558	if (!irqflags)
   1559		irqflags = IRQF_TRIGGER_FALLING;
   1560
   1561	error = devm_request_threaded_irq(&client->dev, client->irq,
   1562					  NULL, elants_i2c_irq,
   1563					  irqflags | IRQF_ONESHOT,
   1564					  client->name, ts);
   1565	if (error) {
   1566		dev_err(&client->dev, "Failed to register interrupt\n");
   1567		return error;
   1568	}
   1569
   1570	/*
   1571	 * Systems using device tree should set up wakeup via DTS,
   1572	 * the rest will configure device as wakeup source by default.
   1573	 */
   1574	if (!client->dev.of_node)
   1575		device_init_wakeup(&client->dev, true);
   1576
   1577	error = devm_device_add_group(&client->dev, &elants_attribute_group);
   1578	if (error) {
   1579		dev_err(&client->dev, "failed to create sysfs attributes: %d\n",
   1580			error);
   1581		return error;
   1582	}
   1583
   1584	return 0;
   1585}
   1586
   1587static int __maybe_unused elants_i2c_suspend(struct device *dev)
   1588{
   1589	struct i2c_client *client = to_i2c_client(dev);
   1590	struct elants_data *ts = i2c_get_clientdata(client);
   1591	const u8 set_sleep_cmd[] = {
   1592		CMD_HEADER_WRITE, E_POWER_STATE_SLEEP, 0x00, 0x01
   1593	};
   1594	int retry_cnt;
   1595	int error;
   1596
   1597	/* Command not support in IAP recovery mode */
   1598	if (ts->iap_mode != ELAN_IAP_OPERATIONAL)
   1599		return -EBUSY;
   1600
   1601	disable_irq(client->irq);
   1602
   1603	if (device_may_wakeup(dev)) {
   1604		/*
   1605		 * The device will automatically enter idle mode
   1606		 * that has reduced power consumption.
   1607		 */
   1608		ts->wake_irq_enabled = (enable_irq_wake(client->irq) == 0);
   1609	} else if (ts->keep_power_in_suspend) {
   1610		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
   1611			error = elants_i2c_send(client, set_sleep_cmd,
   1612						sizeof(set_sleep_cmd));
   1613			if (!error)
   1614				break;
   1615
   1616			dev_err(&client->dev,
   1617				"suspend command failed: %d\n", error);
   1618		}
   1619	} else {
   1620		elants_i2c_power_off(ts);
   1621	}
   1622
   1623	return 0;
   1624}
   1625
   1626static int __maybe_unused elants_i2c_resume(struct device *dev)
   1627{
   1628	struct i2c_client *client = to_i2c_client(dev);
   1629	struct elants_data *ts = i2c_get_clientdata(client);
   1630	const u8 set_active_cmd[] = {
   1631		CMD_HEADER_WRITE, E_POWER_STATE_RESUME, 0x00, 0x01
   1632	};
   1633	int retry_cnt;
   1634	int error;
   1635
   1636	if (device_may_wakeup(dev)) {
   1637		if (ts->wake_irq_enabled)
   1638			disable_irq_wake(client->irq);
   1639		elants_i2c_sw_reset(client);
   1640	} else if (ts->keep_power_in_suspend) {
   1641		for (retry_cnt = 0; retry_cnt < MAX_RETRIES; retry_cnt++) {
   1642			error = elants_i2c_send(client, set_active_cmd,
   1643						sizeof(set_active_cmd));
   1644			if (!error)
   1645				break;
   1646
   1647			dev_err(&client->dev,
   1648				"resume command failed: %d\n", error);
   1649		}
   1650	} else {
   1651		elants_i2c_power_on(ts);
   1652		elants_i2c_initialize(ts);
   1653	}
   1654
   1655	ts->state = ELAN_STATE_NORMAL;
   1656	enable_irq(client->irq);
   1657
   1658	return 0;
   1659}
   1660
   1661static SIMPLE_DEV_PM_OPS(elants_i2c_pm_ops,
   1662			 elants_i2c_suspend, elants_i2c_resume);
   1663
   1664static const struct i2c_device_id elants_i2c_id[] = {
   1665	{ DEVICE_NAME, EKTH3500 },
   1666	{ "ekth3500", EKTH3500 },
   1667	{ "ektf3624", EKTF3624 },
   1668	{ }
   1669};
   1670MODULE_DEVICE_TABLE(i2c, elants_i2c_id);
   1671
   1672#ifdef CONFIG_ACPI
   1673static const struct acpi_device_id elants_acpi_id[] = {
   1674	{ "ELAN0001", EKTH3500 },
   1675	{ }
   1676};
   1677MODULE_DEVICE_TABLE(acpi, elants_acpi_id);
   1678#endif
   1679
   1680#ifdef CONFIG_OF
   1681static const struct of_device_id elants_of_match[] = {
   1682	{ .compatible = "elan,ekth3500", .data = (void *)EKTH3500 },
   1683	{ .compatible = "elan,ektf3624", .data = (void *)EKTF3624 },
   1684	{ /* sentinel */ }
   1685};
   1686MODULE_DEVICE_TABLE(of, elants_of_match);
   1687#endif
   1688
   1689static struct i2c_driver elants_i2c_driver = {
   1690	.probe_new = elants_i2c_probe,
   1691	.id_table = elants_i2c_id,
   1692	.driver = {
   1693		.name = DEVICE_NAME,
   1694		.pm = &elants_i2c_pm_ops,
   1695		.acpi_match_table = ACPI_PTR(elants_acpi_id),
   1696		.of_match_table = of_match_ptr(elants_of_match),
   1697		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
   1698	},
   1699};
   1700module_i2c_driver(elants_i2c_driver);
   1701
   1702MODULE_AUTHOR("Scott Liu <scott.liu@emc.com.tw>");
   1703MODULE_DESCRIPTION("Elan I2c Touchscreen driver");
   1704MODULE_LICENSE("GPL");