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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ili210x.c (26824B)


      1// SPDX-License-Identifier: GPL-2.0-only
      2#include <linux/crc-ccitt.h>
      3#include <linux/delay.h>
      4#include <linux/gpio/consumer.h>
      5#include <linux/i2c.h>
      6#include <linux/ihex.h>
      7#include <linux/input.h>
      8#include <linux/input/mt.h>
      9#include <linux/input/touchscreen.h>
     10#include <linux/interrupt.h>
     11#include <linux/module.h>
     12#include <linux/of_device.h>
     13#include <linux/sizes.h>
     14#include <linux/slab.h>
     15#include <asm/unaligned.h>
     16
     17#define ILI2XXX_POLL_PERIOD	15
     18
     19#define ILI210X_DATA_SIZE	64
     20#define ILI211X_DATA_SIZE	43
     21#define ILI251X_DATA_SIZE1	31
     22#define ILI251X_DATA_SIZE2	20
     23
     24/* Touchscreen commands */
     25#define REG_TOUCHDATA		0x10
     26#define REG_PANEL_INFO		0x20
     27#define REG_FIRMWARE_VERSION	0x40
     28#define REG_PROTOCOL_VERSION	0x42
     29#define REG_KERNEL_VERSION	0x61
     30#define REG_IC_BUSY		0x80
     31#define REG_IC_BUSY_NOT_BUSY	0x50
     32#define REG_GET_MODE		0xc0
     33#define REG_GET_MODE_AP		0x5a
     34#define REG_GET_MODE_BL		0x55
     35#define REG_SET_MODE_AP		0xc1
     36#define REG_SET_MODE_BL		0xc2
     37#define REG_WRITE_DATA		0xc3
     38#define REG_WRITE_ENABLE	0xc4
     39#define REG_READ_DATA_CRC	0xc7
     40#define REG_CALIBRATE		0xcc
     41
     42#define ILI251X_FW_FILENAME	"ilitek/ili251x.bin"
     43
     44struct ili2xxx_chip {
     45	int (*read_reg)(struct i2c_client *client, u8 reg,
     46			void *buf, size_t len);
     47	int (*get_touch_data)(struct i2c_client *client, u8 *data);
     48	bool (*parse_touch_data)(const u8 *data, unsigned int finger,
     49				 unsigned int *x, unsigned int *y,
     50				 unsigned int *z);
     51	bool (*continue_polling)(const u8 *data, bool touch);
     52	unsigned int max_touches;
     53	unsigned int resolution;
     54	bool has_calibrate_reg;
     55	bool has_firmware_proto;
     56	bool has_pressure_reg;
     57};
     58
     59struct ili210x {
     60	struct i2c_client *client;
     61	struct input_dev *input;
     62	struct gpio_desc *reset_gpio;
     63	struct touchscreen_properties prop;
     64	const struct ili2xxx_chip *chip;
     65	u8 version_firmware[8];
     66	u8 version_kernel[5];
     67	u8 version_proto[2];
     68	u8 ic_mode[2];
     69	bool stop;
     70};
     71
     72static int ili210x_read_reg(struct i2c_client *client,
     73			    u8 reg, void *buf, size_t len)
     74{
     75	struct i2c_msg msg[] = {
     76		{
     77			.addr	= client->addr,
     78			.flags	= 0,
     79			.len	= 1,
     80			.buf	= &reg,
     81		},
     82		{
     83			.addr	= client->addr,
     84			.flags	= I2C_M_RD,
     85			.len	= len,
     86			.buf	= buf,
     87		}
     88	};
     89	int error, ret;
     90
     91	ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg));
     92	if (ret != ARRAY_SIZE(msg)) {
     93		error = ret < 0 ? ret : -EIO;
     94		dev_err(&client->dev, "%s failed: %d\n", __func__, error);
     95		return error;
     96	}
     97
     98	return 0;
     99}
    100
    101static int ili210x_read_touch_data(struct i2c_client *client, u8 *data)
    102{
    103	return ili210x_read_reg(client, REG_TOUCHDATA,
    104				data, ILI210X_DATA_SIZE);
    105}
    106
    107static bool ili210x_touchdata_to_coords(const u8 *touchdata,
    108					unsigned int finger,
    109					unsigned int *x, unsigned int *y,
    110					unsigned int *z)
    111{
    112	if (!(touchdata[0] & BIT(finger)))
    113		return false;
    114
    115	*x = get_unaligned_be16(touchdata + 1 + (finger * 4) + 0);
    116	*y = get_unaligned_be16(touchdata + 1 + (finger * 4) + 2);
    117
    118	return true;
    119}
    120
    121static bool ili210x_check_continue_polling(const u8 *data, bool touch)
    122{
    123	return data[0] & 0xf3;
    124}
    125
    126static const struct ili2xxx_chip ili210x_chip = {
    127	.read_reg		= ili210x_read_reg,
    128	.get_touch_data		= ili210x_read_touch_data,
    129	.parse_touch_data	= ili210x_touchdata_to_coords,
    130	.continue_polling	= ili210x_check_continue_polling,
    131	.max_touches		= 2,
    132	.has_calibrate_reg	= true,
    133};
    134
    135static int ili211x_read_touch_data(struct i2c_client *client, u8 *data)
    136{
    137	s16 sum = 0;
    138	int error;
    139	int ret;
    140	int i;
    141
    142	ret = i2c_master_recv(client, data, ILI211X_DATA_SIZE);
    143	if (ret != ILI211X_DATA_SIZE) {
    144		error = ret < 0 ? ret : -EIO;
    145		dev_err(&client->dev, "%s failed: %d\n", __func__, error);
    146		return error;
    147	}
    148
    149	/* This chip uses custom checksum at the end of data */
    150	for (i = 0; i < ILI211X_DATA_SIZE - 1; i++)
    151		sum = (sum + data[i]) & 0xff;
    152
    153	if ((-sum & 0xff) != data[ILI211X_DATA_SIZE - 1]) {
    154		dev_err(&client->dev,
    155			"CRC error (crc=0x%02x expected=0x%02x)\n",
    156			sum, data[ILI211X_DATA_SIZE - 1]);
    157		return -EIO;
    158	}
    159
    160	return 0;
    161}
    162
    163static bool ili211x_touchdata_to_coords(const u8 *touchdata,
    164					unsigned int finger,
    165					unsigned int *x, unsigned int *y,
    166					unsigned int *z)
    167{
    168	u32 data;
    169
    170	data = get_unaligned_be32(touchdata + 1 + (finger * 4) + 0);
    171	if (data == 0xffffffff)	/* Finger up */
    172		return false;
    173
    174	*x = ((touchdata[1 + (finger * 4) + 0] & 0xf0) << 4) |
    175	     touchdata[1 + (finger * 4) + 1];
    176	*y = ((touchdata[1 + (finger * 4) + 0] & 0x0f) << 8) |
    177	     touchdata[1 + (finger * 4) + 2];
    178
    179	return true;
    180}
    181
    182static bool ili211x_decline_polling(const u8 *data, bool touch)
    183{
    184	return false;
    185}
    186
    187static const struct ili2xxx_chip ili211x_chip = {
    188	.read_reg		= ili210x_read_reg,
    189	.get_touch_data		= ili211x_read_touch_data,
    190	.parse_touch_data	= ili211x_touchdata_to_coords,
    191	.continue_polling	= ili211x_decline_polling,
    192	.max_touches		= 10,
    193	.resolution		= 2048,
    194};
    195
    196static bool ili212x_touchdata_to_coords(const u8 *touchdata,
    197					unsigned int finger,
    198					unsigned int *x, unsigned int *y,
    199					unsigned int *z)
    200{
    201	u16 val;
    202
    203	val = get_unaligned_be16(touchdata + 3 + (finger * 5) + 0);
    204	if (!(val & BIT(15)))	/* Touch indication */
    205		return false;
    206
    207	*x = val & 0x3fff;
    208	*y = get_unaligned_be16(touchdata + 3 + (finger * 5) + 2);
    209
    210	return true;
    211}
    212
    213static bool ili212x_check_continue_polling(const u8 *data, bool touch)
    214{
    215	return touch;
    216}
    217
    218static const struct ili2xxx_chip ili212x_chip = {
    219	.read_reg		= ili210x_read_reg,
    220	.get_touch_data		= ili210x_read_touch_data,
    221	.parse_touch_data	= ili212x_touchdata_to_coords,
    222	.continue_polling	= ili212x_check_continue_polling,
    223	.max_touches		= 10,
    224	.has_calibrate_reg	= true,
    225};
    226
    227static int ili251x_read_reg_common(struct i2c_client *client,
    228				   u8 reg, void *buf, size_t len,
    229				   unsigned int delay)
    230{
    231	int error;
    232	int ret;
    233
    234	ret = i2c_master_send(client, &reg, 1);
    235	if (ret == 1) {
    236		if (delay)
    237			usleep_range(delay, delay + 500);
    238
    239		ret = i2c_master_recv(client, buf, len);
    240		if (ret == len)
    241			return 0;
    242	}
    243
    244	error = ret < 0 ? ret : -EIO;
    245	dev_err(&client->dev, "%s failed: %d\n", __func__, error);
    246	return ret;
    247}
    248
    249static int ili251x_read_reg(struct i2c_client *client,
    250			    u8 reg, void *buf, size_t len)
    251{
    252	return ili251x_read_reg_common(client, reg, buf, len, 5000);
    253}
    254
    255static int ili251x_read_touch_data(struct i2c_client *client, u8 *data)
    256{
    257	int error;
    258
    259	error = ili251x_read_reg_common(client, REG_TOUCHDATA,
    260					data, ILI251X_DATA_SIZE1, 0);
    261	if (!error && data[0] == 2) {
    262		error = i2c_master_recv(client, data + ILI251X_DATA_SIZE1,
    263					ILI251X_DATA_SIZE2);
    264		if (error >= 0 && error != ILI251X_DATA_SIZE2)
    265			error = -EIO;
    266	}
    267
    268	return error;
    269}
    270
    271static bool ili251x_touchdata_to_coords(const u8 *touchdata,
    272					unsigned int finger,
    273					unsigned int *x, unsigned int *y,
    274					unsigned int *z)
    275{
    276	u16 val;
    277
    278	val = get_unaligned_be16(touchdata + 1 + (finger * 5) + 0);
    279	if (!(val & BIT(15)))	/* Touch indication */
    280		return false;
    281
    282	*x = val & 0x3fff;
    283	*y = get_unaligned_be16(touchdata + 1 + (finger * 5) + 2);
    284	*z = touchdata[1 + (finger * 5) + 4];
    285
    286	return true;
    287}
    288
    289static bool ili251x_check_continue_polling(const u8 *data, bool touch)
    290{
    291	return touch;
    292}
    293
    294static const struct ili2xxx_chip ili251x_chip = {
    295	.read_reg		= ili251x_read_reg,
    296	.get_touch_data		= ili251x_read_touch_data,
    297	.parse_touch_data	= ili251x_touchdata_to_coords,
    298	.continue_polling	= ili251x_check_continue_polling,
    299	.max_touches		= 10,
    300	.has_calibrate_reg	= true,
    301	.has_firmware_proto	= true,
    302	.has_pressure_reg	= true,
    303};
    304
    305static bool ili210x_report_events(struct ili210x *priv, u8 *touchdata)
    306{
    307	struct input_dev *input = priv->input;
    308	int i;
    309	bool contact = false, touch;
    310	unsigned int x = 0, y = 0, z = 0;
    311
    312	for (i = 0; i < priv->chip->max_touches; i++) {
    313		touch = priv->chip->parse_touch_data(touchdata, i, &x, &y, &z);
    314
    315		input_mt_slot(input, i);
    316		if (input_mt_report_slot_state(input, MT_TOOL_FINGER, touch)) {
    317			touchscreen_report_pos(input, &priv->prop, x, y, true);
    318			if (priv->chip->has_pressure_reg)
    319				input_report_abs(input, ABS_MT_PRESSURE, z);
    320			contact = true;
    321		}
    322	}
    323
    324	input_mt_report_pointer_emulation(input, false);
    325	input_sync(input);
    326
    327	return contact;
    328}
    329
    330static irqreturn_t ili210x_irq(int irq, void *irq_data)
    331{
    332	struct ili210x *priv = irq_data;
    333	struct i2c_client *client = priv->client;
    334	const struct ili2xxx_chip *chip = priv->chip;
    335	u8 touchdata[ILI210X_DATA_SIZE] = { 0 };
    336	bool keep_polling;
    337	ktime_t time_next;
    338	s64 time_delta;
    339	bool touch;
    340	int error;
    341
    342	do {
    343		time_next = ktime_add_ms(ktime_get(), ILI2XXX_POLL_PERIOD);
    344		error = chip->get_touch_data(client, touchdata);
    345		if (error) {
    346			dev_err(&client->dev,
    347				"Unable to get touch data: %d\n", error);
    348			break;
    349		}
    350
    351		touch = ili210x_report_events(priv, touchdata);
    352		keep_polling = chip->continue_polling(touchdata, touch);
    353		if (keep_polling) {
    354			time_delta = ktime_us_delta(time_next, ktime_get());
    355			if (time_delta > 0)
    356				usleep_range(time_delta, time_delta + 1000);
    357		}
    358	} while (!priv->stop && keep_polling);
    359
    360	return IRQ_HANDLED;
    361}
    362
    363static int ili251x_firmware_update_resolution(struct device *dev)
    364{
    365	struct i2c_client *client = to_i2c_client(dev);
    366	struct ili210x *priv = i2c_get_clientdata(client);
    367	u16 resx, resy;
    368	u8 rs[10];
    369	int error;
    370
    371	/* The firmware update blob might have changed the resolution. */
    372	error = priv->chip->read_reg(client, REG_PANEL_INFO, &rs, sizeof(rs));
    373	if (error)
    374		return error;
    375
    376	resx = le16_to_cpup((__le16 *)rs);
    377	resy = le16_to_cpup((__le16 *)(rs + 2));
    378
    379	/* The value reported by the firmware is invalid. */
    380	if (!resx || resx == 0xffff || !resy || resy == 0xffff)
    381		return -EINVAL;
    382
    383	input_abs_set_max(priv->input, ABS_X, resx - 1);
    384	input_abs_set_max(priv->input, ABS_Y, resy - 1);
    385	input_abs_set_max(priv->input, ABS_MT_POSITION_X, resx - 1);
    386	input_abs_set_max(priv->input, ABS_MT_POSITION_Y, resy - 1);
    387
    388	return 0;
    389}
    390
    391static ssize_t ili251x_firmware_update_firmware_version(struct device *dev)
    392{
    393	struct i2c_client *client = to_i2c_client(dev);
    394	struct ili210x *priv = i2c_get_clientdata(client);
    395	int error;
    396	u8 fw[8];
    397
    398	/* Get firmware version */
    399	error = priv->chip->read_reg(client, REG_FIRMWARE_VERSION,
    400				     &fw, sizeof(fw));
    401	if (!error)
    402		memcpy(priv->version_firmware, fw, sizeof(fw));
    403
    404	return error;
    405}
    406
    407static ssize_t ili251x_firmware_update_kernel_version(struct device *dev)
    408{
    409	struct i2c_client *client = to_i2c_client(dev);
    410	struct ili210x *priv = i2c_get_clientdata(client);
    411	int error;
    412	u8 kv[5];
    413
    414	/* Get kernel version */
    415	error = priv->chip->read_reg(client, REG_KERNEL_VERSION,
    416				     &kv, sizeof(kv));
    417	if (!error)
    418		memcpy(priv->version_kernel, kv, sizeof(kv));
    419
    420	return error;
    421}
    422
    423static ssize_t ili251x_firmware_update_protocol_version(struct device *dev)
    424{
    425	struct i2c_client *client = to_i2c_client(dev);
    426	struct ili210x *priv = i2c_get_clientdata(client);
    427	int error;
    428	u8 pv[2];
    429
    430	/* Get protocol version */
    431	error = priv->chip->read_reg(client, REG_PROTOCOL_VERSION,
    432				     &pv, sizeof(pv));
    433	if (!error)
    434		memcpy(priv->version_proto, pv, sizeof(pv));
    435
    436	return error;
    437}
    438
    439static ssize_t ili251x_firmware_update_ic_mode(struct device *dev)
    440{
    441	struct i2c_client *client = to_i2c_client(dev);
    442	struct ili210x *priv = i2c_get_clientdata(client);
    443	int error;
    444	u8 md[2];
    445
    446	/* Get chip boot mode */
    447	error = priv->chip->read_reg(client, REG_GET_MODE, &md, sizeof(md));
    448	if (!error)
    449		memcpy(priv->ic_mode, md, sizeof(md));
    450
    451	return error;
    452}
    453
    454static int ili251x_firmware_update_cached_state(struct device *dev)
    455{
    456	struct i2c_client *client = to_i2c_client(dev);
    457	struct ili210x *priv = i2c_get_clientdata(client);
    458	int error;
    459
    460	if (!priv->chip->has_firmware_proto)
    461		return 0;
    462
    463	/* Wait for firmware to boot and stabilize itself. */
    464	msleep(200);
    465
    466	/* Firmware does report valid information. */
    467	error = ili251x_firmware_update_resolution(dev);
    468	if (error)
    469		return error;
    470
    471	error = ili251x_firmware_update_firmware_version(dev);
    472	if (error)
    473		return error;
    474
    475	error = ili251x_firmware_update_kernel_version(dev);
    476	if (error)
    477		return error;
    478
    479	error = ili251x_firmware_update_protocol_version(dev);
    480	if (error)
    481		return error;
    482
    483	error = ili251x_firmware_update_ic_mode(dev);
    484	if (error)
    485		return error;
    486
    487	return 0;
    488}
    489
    490static ssize_t ili251x_firmware_version_show(struct device *dev,
    491					     struct device_attribute *attr,
    492					     char *buf)
    493{
    494	struct i2c_client *client = to_i2c_client(dev);
    495	struct ili210x *priv = i2c_get_clientdata(client);
    496	u8 *fw = priv->version_firmware;
    497
    498	return sysfs_emit(buf, "%02x%02x.%02x%02x.%02x%02x.%02x%02x\n",
    499			  fw[0], fw[1], fw[2], fw[3],
    500			  fw[4], fw[5], fw[6], fw[7]);
    501}
    502static DEVICE_ATTR(firmware_version, 0444, ili251x_firmware_version_show, NULL);
    503
    504static ssize_t ili251x_kernel_version_show(struct device *dev,
    505					   struct device_attribute *attr,
    506					   char *buf)
    507{
    508	struct i2c_client *client = to_i2c_client(dev);
    509	struct ili210x *priv = i2c_get_clientdata(client);
    510	u8 *kv = priv->version_kernel;
    511
    512	return sysfs_emit(buf, "%02x.%02x.%02x.%02x.%02x\n",
    513			  kv[0], kv[1], kv[2], kv[3], kv[4]);
    514}
    515static DEVICE_ATTR(kernel_version, 0444, ili251x_kernel_version_show, NULL);
    516
    517static ssize_t ili251x_protocol_version_show(struct device *dev,
    518					     struct device_attribute *attr,
    519					     char *buf)
    520{
    521	struct i2c_client *client = to_i2c_client(dev);
    522	struct ili210x *priv = i2c_get_clientdata(client);
    523	u8 *pv = priv->version_proto;
    524
    525	return sysfs_emit(buf, "%02x.%02x\n", pv[0], pv[1]);
    526}
    527static DEVICE_ATTR(protocol_version, 0444, ili251x_protocol_version_show, NULL);
    528
    529static ssize_t ili251x_mode_show(struct device *dev,
    530				 struct device_attribute *attr, char *buf)
    531{
    532	struct i2c_client *client = to_i2c_client(dev);
    533	struct ili210x *priv = i2c_get_clientdata(client);
    534	u8 *md = priv->ic_mode;
    535	char *mode = "AP";
    536
    537	if (md[0] == REG_GET_MODE_AP)		/* Application Mode */
    538		mode = "AP";
    539	else if (md[0] == REG_GET_MODE_BL)	/* BootLoader Mode */
    540		mode = "BL";
    541	else					/* Unknown Mode */
    542		mode = "??";
    543
    544	return sysfs_emit(buf, "%02x.%02x:%s\n", md[0], md[1], mode);
    545}
    546static DEVICE_ATTR(mode, 0444, ili251x_mode_show, NULL);
    547
    548static ssize_t ili210x_calibrate(struct device *dev,
    549				 struct device_attribute *attr,
    550				 const char *buf, size_t count)
    551{
    552	struct i2c_client *client = to_i2c_client(dev);
    553	struct ili210x *priv = i2c_get_clientdata(client);
    554	unsigned long calibrate;
    555	int rc;
    556	u8 cmd = REG_CALIBRATE;
    557
    558	if (kstrtoul(buf, 10, &calibrate))
    559		return -EINVAL;
    560
    561	if (calibrate > 1)
    562		return -EINVAL;
    563
    564	if (calibrate) {
    565		rc = i2c_master_send(priv->client, &cmd, sizeof(cmd));
    566		if (rc != sizeof(cmd))
    567			return -EIO;
    568	}
    569
    570	return count;
    571}
    572static DEVICE_ATTR(calibrate, S_IWUSR, NULL, ili210x_calibrate);
    573
    574static int ili251x_firmware_to_buffer(const struct firmware *fw,
    575				      u8 **buf, u16 *ac_end, u16 *df_end)
    576{
    577	const struct ihex_binrec *rec;
    578	u32 fw_addr, fw_last_addr = 0;
    579	u16 fw_len;
    580	u8 *fw_buf;
    581	int error;
    582
    583	/*
    584	 * The firmware ihex blob can never be bigger than 64 kiB, so make this
    585	 * simple -- allocate a 64 kiB buffer, iterate over the ihex blob records
    586	 * once, copy them all into this buffer at the right locations, and then
    587	 * do all operations on this linear buffer.
    588	 */
    589	fw_buf = kzalloc(SZ_64K, GFP_KERNEL);
    590	if (!fw_buf)
    591		return -ENOMEM;
    592
    593	rec = (const struct ihex_binrec *)fw->data;
    594	while (rec) {
    595		fw_addr = be32_to_cpu(rec->addr);
    596		fw_len = be16_to_cpu(rec->len);
    597
    598		/* The last 32 Byte firmware block can be 0xffe0 */
    599		if (fw_addr + fw_len > SZ_64K || fw_addr > SZ_64K - 32) {
    600			error = -EFBIG;
    601			goto err_big;
    602		}
    603
    604		/* Find the last address before DF start address, that is AC end */
    605		if (fw_addr == 0xf000)
    606			*ac_end = fw_last_addr;
    607		fw_last_addr = fw_addr + fw_len;
    608
    609		memcpy(fw_buf + fw_addr, rec->data, fw_len);
    610		rec = ihex_next_binrec(rec);
    611	}
    612
    613	/* DF end address is the last address in the firmware blob */
    614	*df_end = fw_addr + fw_len;
    615	*buf = fw_buf;
    616	return 0;
    617
    618err_big:
    619	kfree(fw_buf);
    620	return error;
    621}
    622
    623/* Switch mode between Application and BootLoader */
    624static int ili251x_switch_ic_mode(struct i2c_client *client, u8 cmd_mode)
    625{
    626	struct ili210x *priv = i2c_get_clientdata(client);
    627	u8 cmd_wren[3] = { REG_WRITE_ENABLE, 0x5a, 0xa5 };
    628	u8 md[2];
    629	int error;
    630
    631	error = priv->chip->read_reg(client, REG_GET_MODE, md, sizeof(md));
    632	if (error)
    633		return error;
    634	/* Mode already set */
    635	if ((cmd_mode == REG_SET_MODE_AP && md[0] == REG_GET_MODE_AP) ||
    636	    (cmd_mode == REG_SET_MODE_BL && md[0] == REG_GET_MODE_BL))
    637		return 0;
    638
    639	/* Unlock writes */
    640	error = i2c_master_send(client, cmd_wren, sizeof(cmd_wren));
    641	if (error != sizeof(cmd_wren))
    642		return -EINVAL;
    643
    644	mdelay(20);
    645
    646	/* Select mode (BootLoader or Application) */
    647	error = i2c_master_send(client, &cmd_mode, 1);
    648	if (error != 1)
    649		return -EINVAL;
    650
    651	mdelay(200);	/* Reboot into bootloader takes a lot of time ... */
    652
    653	/* Read back mode */
    654	error = priv->chip->read_reg(client, REG_GET_MODE, md, sizeof(md));
    655	if (error)
    656		return error;
    657	/* Check if mode is correct now. */
    658	if ((cmd_mode == REG_SET_MODE_AP && md[0] == REG_GET_MODE_AP) ||
    659	    (cmd_mode == REG_SET_MODE_BL && md[0] == REG_GET_MODE_BL))
    660		return 0;
    661
    662	return -EINVAL;
    663}
    664
    665static int ili251x_firmware_busy(struct i2c_client *client)
    666{
    667	struct ili210x *priv = i2c_get_clientdata(client);
    668	int error, i = 0;
    669	u8 data;
    670
    671	do {
    672		/* The read_reg already contains suitable delay */
    673		error = priv->chip->read_reg(client, REG_IC_BUSY, &data, 1);
    674		if (error)
    675			return error;
    676		if (i++ == 100000)
    677			return -ETIMEDOUT;
    678	} while (data != REG_IC_BUSY_NOT_BUSY);
    679
    680	return 0;
    681}
    682
    683static int ili251x_firmware_write_to_ic(struct device *dev, u8 *fwbuf,
    684					u16 start, u16 end, u8 dataflash)
    685{
    686	struct i2c_client *client = to_i2c_client(dev);
    687	struct ili210x *priv = i2c_get_clientdata(client);
    688	u8 cmd_crc = REG_READ_DATA_CRC;
    689	u8 crcrb[4] = { 0 };
    690	u8 fw_data[33];
    691	u16 fw_addr;
    692	int error;
    693
    694	/*
    695	 * The DF (dataflash) needs 2 bytes offset for unknown reasons,
    696	 * the AC (application) has 2 bytes CRC16-CCITT at the end.
    697	 */
    698	u16 crc = crc_ccitt(0, fwbuf + start + (dataflash ? 2 : 0),
    699			    end - start - 2);
    700
    701	/* Unlock write to either AC (application) or DF (dataflash) area */
    702	u8 cmd_wr[10] = {
    703		REG_WRITE_ENABLE, 0x5a, 0xa5, dataflash,
    704		(end >> 16) & 0xff, (end >> 8) & 0xff, end & 0xff,
    705		(crc >> 16) & 0xff, (crc >> 8) & 0xff, crc & 0xff
    706	};
    707
    708	error = i2c_master_send(client, cmd_wr, sizeof(cmd_wr));
    709	if (error != sizeof(cmd_wr))
    710		return -EINVAL;
    711
    712	error = ili251x_firmware_busy(client);
    713	if (error)
    714		return error;
    715
    716	for (fw_addr = start; fw_addr < end; fw_addr += 32) {
    717		fw_data[0] = REG_WRITE_DATA;
    718		memcpy(&(fw_data[1]), fwbuf + fw_addr, 32);
    719		error = i2c_master_send(client, fw_data, 33);
    720		if (error != sizeof(fw_data))
    721			return error;
    722		error = ili251x_firmware_busy(client);
    723		if (error)
    724			return error;
    725	}
    726
    727	error = i2c_master_send(client, &cmd_crc, 1);
    728	if (error != 1)
    729		return -EINVAL;
    730
    731	error = ili251x_firmware_busy(client);
    732	if (error)
    733		return error;
    734
    735	error = priv->chip->read_reg(client, REG_READ_DATA_CRC,
    736				   &crcrb, sizeof(crcrb));
    737	if (error)
    738		return error;
    739
    740	/* Check CRC readback */
    741	if ((crcrb[0] != (crc & 0xff)) || crcrb[1] != ((crc >> 8) & 0xff))
    742		return -EINVAL;
    743
    744	return 0;
    745}
    746
    747static int ili251x_firmware_reset(struct i2c_client *client)
    748{
    749	u8 cmd_reset[2] = { 0xf2, 0x01 };
    750	int error;
    751
    752	error = i2c_master_send(client, cmd_reset, sizeof(cmd_reset));
    753	if (error != sizeof(cmd_reset))
    754		return -EINVAL;
    755
    756	return ili251x_firmware_busy(client);
    757}
    758
    759static void ili210x_hardware_reset(struct gpio_desc *reset_gpio)
    760{
    761	/* Reset the controller */
    762	gpiod_set_value_cansleep(reset_gpio, 1);
    763	usleep_range(12000, 15000);
    764	gpiod_set_value_cansleep(reset_gpio, 0);
    765	msleep(300);
    766}
    767
    768static ssize_t ili210x_firmware_update_store(struct device *dev,
    769					     struct device_attribute *attr,
    770					     const char *buf, size_t count)
    771{
    772	struct i2c_client *client = to_i2c_client(dev);
    773	struct ili210x *priv = i2c_get_clientdata(client);
    774	const char *fwname = ILI251X_FW_FILENAME;
    775	const struct firmware *fw;
    776	u16 ac_end, df_end;
    777	u8 *fwbuf;
    778	int error;
    779	int i;
    780
    781	error = request_ihex_firmware(&fw, fwname, dev);
    782	if (error) {
    783		dev_err(dev, "Failed to request firmware %s, error=%d\n",
    784			fwname, error);
    785		return error;
    786	}
    787
    788	error = ili251x_firmware_to_buffer(fw, &fwbuf, &ac_end, &df_end);
    789	release_firmware(fw);
    790	if (error)
    791		return error;
    792
    793	/*
    794	 * Disable touchscreen IRQ, so that we would not get spurious touch
    795	 * interrupt during firmware update, and so that the IRQ handler won't
    796	 * trigger and interfere with the firmware update. There is no bit in
    797	 * the touch controller to disable the IRQs during update, so we have
    798	 * to do it this way here.
    799	 */
    800	disable_irq(client->irq);
    801
    802	dev_dbg(dev, "Firmware update started, firmware=%s\n", fwname);
    803
    804	ili210x_hardware_reset(priv->reset_gpio);
    805
    806	error = ili251x_firmware_reset(client);
    807	if (error)
    808		goto exit;
    809
    810	/* This may not succeed on first try, so re-try a few times. */
    811	for (i = 0; i < 5; i++) {
    812		error = ili251x_switch_ic_mode(client, REG_SET_MODE_BL);
    813		if (!error)
    814			break;
    815	}
    816
    817	if (error)
    818		goto exit;
    819
    820	dev_dbg(dev, "IC is now in BootLoader mode\n");
    821
    822	msleep(200);	/* The bootloader seems to need some time too. */
    823
    824	error = ili251x_firmware_write_to_ic(dev, fwbuf, 0xf000, df_end, 1);
    825	if (error) {
    826		dev_err(dev, "DF firmware update failed, error=%d\n", error);
    827		goto exit;
    828	}
    829
    830	dev_dbg(dev, "DataFlash firmware written\n");
    831
    832	error = ili251x_firmware_write_to_ic(dev, fwbuf, 0x2000, ac_end, 0);
    833	if (error) {
    834		dev_err(dev, "AC firmware update failed, error=%d\n", error);
    835		goto exit;
    836	}
    837
    838	dev_dbg(dev, "Application firmware written\n");
    839
    840	/* This may not succeed on first try, so re-try a few times. */
    841	for (i = 0; i < 5; i++) {
    842		error = ili251x_switch_ic_mode(client, REG_SET_MODE_AP);
    843		if (!error)
    844			break;
    845	}
    846
    847	if (error)
    848		goto exit;
    849
    850	dev_dbg(dev, "IC is now in Application mode\n");
    851
    852	error = ili251x_firmware_update_cached_state(dev);
    853	if (error)
    854		goto exit;
    855
    856	error = count;
    857
    858exit:
    859	ili210x_hardware_reset(priv->reset_gpio);
    860	dev_dbg(dev, "Firmware update ended, error=%i\n", error);
    861	enable_irq(client->irq);
    862	kfree(fwbuf);
    863	return error;
    864}
    865
    866static DEVICE_ATTR(firmware_update, 0200, NULL, ili210x_firmware_update_store);
    867
    868static struct attribute *ili210x_attributes[] = {
    869	&dev_attr_calibrate.attr,
    870	&dev_attr_firmware_update.attr,
    871	&dev_attr_firmware_version.attr,
    872	&dev_attr_kernel_version.attr,
    873	&dev_attr_protocol_version.attr,
    874	&dev_attr_mode.attr,
    875	NULL,
    876};
    877
    878static umode_t ili210x_attributes_visible(struct kobject *kobj,
    879					  struct attribute *attr, int index)
    880{
    881	struct device *dev = kobj_to_dev(kobj);
    882	struct i2c_client *client = to_i2c_client(dev);
    883	struct ili210x *priv = i2c_get_clientdata(client);
    884
    885	/* Calibrate is present on all ILI2xxx which have calibrate register */
    886	if (attr == &dev_attr_calibrate.attr)
    887		return priv->chip->has_calibrate_reg ? attr->mode : 0;
    888
    889	/* Firmware/Kernel/Protocol/BootMode is implememted only for ILI251x */
    890	if (!priv->chip->has_firmware_proto)
    891		return 0;
    892
    893	return attr->mode;
    894}
    895
    896static const struct attribute_group ili210x_attr_group = {
    897	.attrs = ili210x_attributes,
    898	.is_visible = ili210x_attributes_visible,
    899};
    900
    901static void ili210x_power_down(void *data)
    902{
    903	struct gpio_desc *reset_gpio = data;
    904
    905	gpiod_set_value_cansleep(reset_gpio, 1);
    906}
    907
    908static void ili210x_stop(void *data)
    909{
    910	struct ili210x *priv = data;
    911
    912	/* Tell ISR to quit even if there is a contact. */
    913	priv->stop = true;
    914}
    915
    916static int ili210x_i2c_probe(struct i2c_client *client,
    917			     const struct i2c_device_id *id)
    918{
    919	struct device *dev = &client->dev;
    920	const struct ili2xxx_chip *chip;
    921	struct ili210x *priv;
    922	struct gpio_desc *reset_gpio;
    923	struct input_dev *input;
    924	int error;
    925	unsigned int max_xy;
    926
    927	dev_dbg(dev, "Probing for ILI210X I2C Touschreen driver");
    928
    929	chip = device_get_match_data(dev);
    930	if (!chip && id)
    931		chip = (const struct ili2xxx_chip *)id->driver_data;
    932	if (!chip) {
    933		dev_err(&client->dev, "unknown device model\n");
    934		return -ENODEV;
    935	}
    936
    937	if (client->irq <= 0) {
    938		dev_err(dev, "No IRQ!\n");
    939		return -EINVAL;
    940	}
    941
    942	reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
    943	if (IS_ERR(reset_gpio))
    944		return PTR_ERR(reset_gpio);
    945
    946	if (reset_gpio) {
    947		error = devm_add_action_or_reset(dev, ili210x_power_down,
    948						 reset_gpio);
    949		if (error)
    950			return error;
    951
    952		ili210x_hardware_reset(reset_gpio);
    953	}
    954
    955	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
    956	if (!priv)
    957		return -ENOMEM;
    958
    959	input = devm_input_allocate_device(dev);
    960	if (!input)
    961		return -ENOMEM;
    962
    963	priv->client = client;
    964	priv->input = input;
    965	priv->reset_gpio = reset_gpio;
    966	priv->chip = chip;
    967	i2c_set_clientdata(client, priv);
    968
    969	/* Setup input device */
    970	input->name = "ILI210x Touchscreen";
    971	input->id.bustype = BUS_I2C;
    972
    973	/* Multi touch */
    974	max_xy = (chip->resolution ?: SZ_64K) - 1;
    975	input_set_abs_params(input, ABS_MT_POSITION_X, 0, max_xy, 0, 0);
    976	input_set_abs_params(input, ABS_MT_POSITION_Y, 0, max_xy, 0, 0);
    977	if (priv->chip->has_pressure_reg)
    978		input_set_abs_params(input, ABS_MT_PRESSURE, 0, 0xa, 0, 0);
    979	error = ili251x_firmware_update_cached_state(dev);
    980	if (error) {
    981		dev_err(dev, "Unable to cache firmware information, err: %d\n",
    982			error);
    983		return error;
    984	}
    985	touchscreen_parse_properties(input, true, &priv->prop);
    986
    987	error = input_mt_init_slots(input, priv->chip->max_touches,
    988				    INPUT_MT_DIRECT);
    989	if (error) {
    990		dev_err(dev, "Unable to set up slots, err: %d\n", error);
    991		return error;
    992	}
    993
    994	error = devm_request_threaded_irq(dev, client->irq, NULL, ili210x_irq,
    995					  IRQF_ONESHOT, client->name, priv);
    996	if (error) {
    997		dev_err(dev, "Unable to request touchscreen IRQ, err: %d\n",
    998			error);
    999		return error;
   1000	}
   1001
   1002	error = devm_add_action_or_reset(dev, ili210x_stop, priv);
   1003	if (error)
   1004		return error;
   1005
   1006	error = devm_device_add_group(dev, &ili210x_attr_group);
   1007	if (error) {
   1008		dev_err(dev, "Unable to create sysfs attributes, err: %d\n",
   1009			error);
   1010		return error;
   1011	}
   1012
   1013	error = input_register_device(priv->input);
   1014	if (error) {
   1015		dev_err(dev, "Cannot register input device, err: %d\n", error);
   1016		return error;
   1017	}
   1018
   1019	return 0;
   1020}
   1021
   1022static const struct i2c_device_id ili210x_i2c_id[] = {
   1023	{ "ili210x", (long)&ili210x_chip },
   1024	{ "ili2117", (long)&ili211x_chip },
   1025	{ "ili2120", (long)&ili212x_chip },
   1026	{ "ili251x", (long)&ili251x_chip },
   1027	{ }
   1028};
   1029MODULE_DEVICE_TABLE(i2c, ili210x_i2c_id);
   1030
   1031static const struct of_device_id ili210x_dt_ids[] = {
   1032	{ .compatible = "ilitek,ili210x", .data = &ili210x_chip },
   1033	{ .compatible = "ilitek,ili2117", .data = &ili211x_chip },
   1034	{ .compatible = "ilitek,ili2120", .data = &ili212x_chip },
   1035	{ .compatible = "ilitek,ili251x", .data = &ili251x_chip },
   1036	{ }
   1037};
   1038MODULE_DEVICE_TABLE(of, ili210x_dt_ids);
   1039
   1040static struct i2c_driver ili210x_ts_driver = {
   1041	.driver = {
   1042		.name = "ili210x_i2c",
   1043		.of_match_table = ili210x_dt_ids,
   1044	},
   1045	.id_table = ili210x_i2c_id,
   1046	.probe = ili210x_i2c_probe,
   1047};
   1048
   1049module_i2c_driver(ili210x_ts_driver);
   1050
   1051MODULE_AUTHOR("Olivier Sobrie <olivier@sobrie.be>");
   1052MODULE_DESCRIPTION("ILI210X I2C Touchscreen Driver");
   1053MODULE_LICENSE("GPL");