1/*
2 * Weida HiTech WDT87xx TouchScreen I2C driver
3 *
4 * Copyright (c) 2015  Weida Hi-Tech Co., Ltd.
5 * HN Chen <hn.chen@weidahitech.com>
6 *
7 * This software is licensed under the terms of the GNU General Public
8 * License, as published by the Free Software Foundation, and
9 * may be copied, distributed, and modified under those terms.
10 */
11
12#include <linux/i2c.h>
13#include <linux/input.h>
14#include <linux/interrupt.h>
15#include <linux/delay.h>
16#include <linux/irq.h>
17#include <linux/io.h>
18#include <linux/module.h>
19#include <linux/slab.h>
20#include <linux/firmware.h>
21#include <linux/input/mt.h>
22#include <linux/acpi.h>
23#include <asm/unaligned.h>
24
25#define WDT87XX_NAME		"wdt87xx_i2c"
26#define WDT87XX_DRV_VER		"0.9.7"
27#define WDT87XX_FW_NAME		"wdt87xx_fw.bin"
28#define WDT87XX_CFG_NAME	"wdt87xx_cfg.bin"
29
30#define MODE_ACTIVE			0x01
31#define MODE_READY			0x02
32#define MODE_IDLE			0x03
33#define MODE_SLEEP			0x04
34#define MODE_STOP			0xFF
35
36#define WDT_MAX_FINGER			10
37#define WDT_RAW_BUF_COUNT		54
38#define WDT_V1_RAW_BUF_COUNT		74
39#define WDT_FIRMWARE_ID			0xa9e368f5
40
41#define PG_SIZE				0x1000
42#define MAX_RETRIES			3
43
44#define MAX_UNIT_AXIS			0x7FFF
45
46#define PKT_READ_SIZE			72
47#define PKT_WRITE_SIZE			80
48
49/* the finger definition of the report event */
50#define FINGER_EV_OFFSET_ID		0
51#define FINGER_EV_OFFSET_X		1
52#define FINGER_EV_OFFSET_Y		3
53#define FINGER_EV_SIZE			5
54
55#define FINGER_EV_V1_OFFSET_ID		0
56#define FINGER_EV_V1_OFFSET_W		1
57#define FINGER_EV_V1_OFFSET_P		2
58#define FINGER_EV_V1_OFFSET_X		3
59#define FINGER_EV_V1_OFFSET_Y		5
60#define FINGER_EV_V1_SIZE		7
61
62/* The definition of a report packet */
63#define TOUCH_PK_OFFSET_REPORT_ID	0
64#define TOUCH_PK_OFFSET_EVENT		1
65#define TOUCH_PK_OFFSET_SCAN_TIME	51
66#define TOUCH_PK_OFFSET_FNGR_NUM	53
67
68#define TOUCH_PK_V1_OFFSET_REPORT_ID	0
69#define TOUCH_PK_V1_OFFSET_EVENT	1
70#define TOUCH_PK_V1_OFFSET_SCAN_TIME	71
71#define TOUCH_PK_V1_OFFSET_FNGR_NUM	73
72
73/* The definition of the controller parameters */
74#define CTL_PARAM_OFFSET_FW_ID		0
75#define CTL_PARAM_OFFSET_PLAT_ID	2
76#define CTL_PARAM_OFFSET_XMLS_ID1	4
77#define CTL_PARAM_OFFSET_XMLS_ID2	6
78#define CTL_PARAM_OFFSET_PHY_CH_X	8
79#define CTL_PARAM_OFFSET_PHY_CH_Y	10
80#define CTL_PARAM_OFFSET_PHY_X0		12
81#define CTL_PARAM_OFFSET_PHY_X1		14
82#define CTL_PARAM_OFFSET_PHY_Y0		16
83#define CTL_PARAM_OFFSET_PHY_Y1		18
84#define CTL_PARAM_OFFSET_PHY_W		22
85#define CTL_PARAM_OFFSET_PHY_H		24
86#define CTL_PARAM_OFFSET_FACTOR		32
87
88/* The definition of the device descriptor */
89#define WDT_GD_DEVICE			1
90#define DEV_DESC_OFFSET_VID		8
91#define DEV_DESC_OFFSET_PID		10
92
93/* Communication commands */
94#define PACKET_SIZE			56
95#define VND_REQ_READ			0x06
96#define VND_READ_DATA			0x07
97#define VND_REQ_WRITE			0x08
98
99#define VND_CMD_START			0x00
100#define VND_CMD_STOP			0x01
101#define VND_CMD_RESET			0x09
102
103#define VND_CMD_ERASE			0x1A
104
105#define VND_GET_CHECKSUM		0x66
106
107#define VND_SET_DATA			0x83
108#define VND_SET_COMMAND_DATA		0x84
109#define VND_SET_CHECKSUM_CALC		0x86
110#define VND_SET_CHECKSUM_LENGTH		0x87
111
112#define VND_CMD_SFLCK			0xFC
113#define VND_CMD_SFUNL			0xFD
114
115#define CMD_SFLCK_KEY			0xC39B
116#define CMD_SFUNL_KEY			0x95DA
117
118#define STRIDX_PLATFORM_ID		0x80
119#define STRIDX_PARAMETERS		0x81
120
121#define CMD_BUF_SIZE			8
122#define PKT_BUF_SIZE			64
123
124/* The definition of the command packet */
125#define CMD_REPORT_ID_OFFSET		0x0
126#define CMD_TYPE_OFFSET			0x1
127#define CMD_INDEX_OFFSET		0x2
128#define CMD_KEY_OFFSET			0x3
129#define CMD_LENGTH_OFFSET		0x4
130#define CMD_DATA_OFFSET			0x8
131
132/* The definition of firmware chunk tags */
133#define FOURCC_ID_RIFF			0x46464952
134#define FOURCC_ID_WHIF			0x46494857
135#define FOURCC_ID_FRMT			0x544D5246
136#define FOURCC_ID_FRWR			0x52575246
137#define FOURCC_ID_CNFG			0x47464E43
138
139#define CHUNK_ID_FRMT			FOURCC_ID_FRMT
140#define CHUNK_ID_FRWR			FOURCC_ID_FRWR
141#define CHUNK_ID_CNFG			FOURCC_ID_CNFG
142
143#define FW_FOURCC1_OFFSET		0
144#define FW_SIZE_OFFSET			4
145#define FW_FOURCC2_OFFSET		8
146#define FW_PAYLOAD_OFFSET		40
147
148#define FW_CHUNK_ID_OFFSET		0
149#define FW_CHUNK_SIZE_OFFSET		4
150#define FW_CHUNK_TGT_START_OFFSET	8
151#define FW_CHUNK_PAYLOAD_LEN_OFFSET	12
152#define FW_CHUNK_SRC_START_OFFSET	16
153#define FW_CHUNK_VERSION_OFFSET		20
154#define FW_CHUNK_ATTR_OFFSET		24
155#define FW_CHUNK_PAYLOAD_OFFSET		32
156
157/* Controller requires minimum 300us between commands */
158#define WDT_COMMAND_DELAY_MS		2
159#define WDT_FLASH_WRITE_DELAY_MS	4
160#define WDT_FW_RESET_TIME		2500
161
162struct wdt87xx_sys_param {
163	u16	fw_id;
164	u16	plat_id;
165	u16	xmls_id1;
166	u16	xmls_id2;
167	u16	phy_ch_x;
168	u16	phy_ch_y;
169	u16	phy_w;
170	u16	phy_h;
171	u16	scaling_factor;
172	u32	max_x;
173	u32	max_y;
174	u16	vendor_id;
175	u16	product_id;
176};
177
178struct wdt87xx_data {
179	struct i2c_client		*client;
180	struct input_dev		*input;
181	/* Mutex for fw update to prevent concurrent access */
182	struct mutex			fw_mutex;
183	struct wdt87xx_sys_param	param;
184	u8				phys[32];
185};
186
187static int wdt87xx_i2c_xfer(struct i2c_client *client,
188			    void *txdata, size_t txlen,
189			    void *rxdata, size_t rxlen)
190{
191	struct i2c_msg msgs[] = {
192		{
193			.addr	= client->addr,
194			.flags	= 0,
195			.len	= txlen,
196			.buf	= txdata,
197		},
198		{
199			.addr	= client->addr,
200			.flags	= I2C_M_RD,
201			.len	= rxlen,
202			.buf	= rxdata,
203		},
204	};
205	int error;
206	int ret;
207
208	ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
209	if (ret != ARRAY_SIZE(msgs)) {
210		error = ret < 0 ? ret : -EIO;
211		dev_err(&client->dev, "%s: i2c transfer failed: %d\n",
212			__func__, error);
213		return error;
214	}
215
216	return 0;
217}
218
219static int wdt87xx_get_desc(struct i2c_client *client, u8 desc_idx,
220			    u8 *buf, size_t len)
221{
222	u8 tx_buf[] = { 0x22, 0x00, 0x10, 0x0E, 0x23, 0x00 };
223	int error;
224
225	tx_buf[2] |= desc_idx & 0xF;
226
227	error = wdt87xx_i2c_xfer(client, tx_buf, sizeof(tx_buf),
228				 buf, len);
229	if (error) {
230		dev_err(&client->dev, "get desc failed: %d\n", error);
231		return error;
232	}
233
234	if (buf[0] != len) {
235		dev_err(&client->dev, "unexpected response to get desc: %d\n",
236			buf[0]);
237		return -EINVAL;
238	}
239
240	mdelay(WDT_COMMAND_DELAY_MS);
241
242	return 0;
243}
244
245static int wdt87xx_get_string(struct i2c_client *client, u8 str_idx,
246			      u8 *buf, size_t len)
247{
248	u8 tx_buf[] = { 0x22, 0x00, 0x13, 0x0E, str_idx, 0x23, 0x00 };
249	u8 rx_buf[PKT_WRITE_SIZE];
250	size_t rx_len = len + 2;
251	int error;
252
253	if (rx_len > sizeof(rx_buf))
254		return -EINVAL;
255
256	error = wdt87xx_i2c_xfer(client, tx_buf, sizeof(tx_buf),
257				 rx_buf, rx_len);
258	if (error) {
259		dev_err(&client->dev, "get string failed: %d\n", error);
260		return error;
261	}
262
263	if (rx_buf[1] != 0x03) {
264		dev_err(&client->dev, "unexpected response to get string: %d\n",
265			rx_buf[1]);
266		return -EINVAL;
267	}
268
269	rx_len = min_t(size_t, len, rx_buf[0]);
270	memcpy(buf, &rx_buf[2], rx_len);
271
272	mdelay(WDT_COMMAND_DELAY_MS);
273
274	return 0;
275}
276
277static int wdt87xx_get_feature(struct i2c_client *client,
278			       u8 *buf, size_t buf_size)
279{
280	u8 tx_buf[8];
281	u8 rx_buf[PKT_WRITE_SIZE];
282	size_t tx_len = 0;
283	size_t rx_len = buf_size + 2;
284	int error;
285
286	if (rx_len > sizeof(rx_buf))
287		return -EINVAL;
288
289	/* Get feature command packet */
290	tx_buf[tx_len++] = 0x22;
291	tx_buf[tx_len++] = 0x00;
292	if (buf[CMD_REPORT_ID_OFFSET] > 0xF) {
293		tx_buf[tx_len++] = 0x30;
294		tx_buf[tx_len++] = 0x02;
295		tx_buf[tx_len++] = buf[CMD_REPORT_ID_OFFSET];
296	} else {
297		tx_buf[tx_len++] = 0x30 | buf[CMD_REPORT_ID_OFFSET];
298		tx_buf[tx_len++] = 0x02;
299	}
300	tx_buf[tx_len++] = 0x23;
301	tx_buf[tx_len++] = 0x00;
302
303	error = wdt87xx_i2c_xfer(client, tx_buf, tx_len, rx_buf, rx_len);
304	if (error) {
305		dev_err(&client->dev, "get feature failed: %d\n", error);
306		return error;
307	}
308
309	rx_len = min_t(size_t, buf_size, get_unaligned_le16(rx_buf));
310	memcpy(buf, &rx_buf[2], rx_len);
311
312	mdelay(WDT_COMMAND_DELAY_MS);
313
314	return 0;
315}
316
317static int wdt87xx_set_feature(struct i2c_client *client,
318			       const u8 *buf, size_t buf_size)
319{
320	u8 tx_buf[PKT_WRITE_SIZE];
321	int tx_len = 0;
322	int error;
323
324	/* Set feature command packet */
325	tx_buf[tx_len++] = 0x22;
326	tx_buf[tx_len++] = 0x00;
327	if (buf[CMD_REPORT_ID_OFFSET] > 0xF) {
328		tx_buf[tx_len++] = 0x30;
329		tx_buf[tx_len++] = 0x03;
330		tx_buf[tx_len++] = buf[CMD_REPORT_ID_OFFSET];
331	} else {
332		tx_buf[tx_len++] = 0x30 | buf[CMD_REPORT_ID_OFFSET];
333		tx_buf[tx_len++] = 0x03;
334	}
335	tx_buf[tx_len++] = 0x23;
336	tx_buf[tx_len++] = 0x00;
337	tx_buf[tx_len++] = (buf_size & 0xFF);
338	tx_buf[tx_len++] = ((buf_size & 0xFF00) >> 8);
339
340	if (tx_len + buf_size > sizeof(tx_buf))
341		return -EINVAL;
342
343	memcpy(&tx_buf[tx_len], buf, buf_size);
344	tx_len += buf_size;
345
346	error = i2c_master_send(client, tx_buf, tx_len);
347	if (error < 0) {
348		dev_err(&client->dev, "set feature failed: %d\n", error);
349		return error;
350	}
351
352	mdelay(WDT_COMMAND_DELAY_MS);
353
354	return 0;
355}
356
357static int wdt87xx_send_command(struct i2c_client *client, int cmd, int value)
358{
359	u8 cmd_buf[CMD_BUF_SIZE];
360
361	/* Set the command packet */
362	cmd_buf[CMD_REPORT_ID_OFFSET] = VND_REQ_WRITE;
363	cmd_buf[CMD_TYPE_OFFSET] = VND_SET_COMMAND_DATA;
364	put_unaligned_le16((u16)cmd, &cmd_buf[CMD_INDEX_OFFSET]);
365
366	switch (cmd) {
367	case VND_CMD_START:
368	case VND_CMD_STOP:
369	case VND_CMD_RESET:
370		/* Mode selector */
371		put_unaligned_le32((value & 0xFF), &cmd_buf[CMD_LENGTH_OFFSET]);
372		break;
373
374	case VND_CMD_SFLCK:
375		put_unaligned_le16(CMD_SFLCK_KEY, &cmd_buf[CMD_KEY_OFFSET]);
376		break;
377
378	case VND_CMD_SFUNL:
379		put_unaligned_le16(CMD_SFUNL_KEY, &cmd_buf[CMD_KEY_OFFSET]);
380		break;
381
382	case VND_CMD_ERASE:
383	case VND_SET_CHECKSUM_CALC:
384	case VND_SET_CHECKSUM_LENGTH:
385		put_unaligned_le32(value, &cmd_buf[CMD_KEY_OFFSET]);
386		break;
387
388	default:
389		cmd_buf[CMD_REPORT_ID_OFFSET] = 0;
390		dev_err(&client->dev, "Invalid command: %d\n", cmd);
391		return -EINVAL;
392	}
393
394	return wdt87xx_set_feature(client, cmd_buf, sizeof(cmd_buf));
395}
396
397static int wdt87xx_sw_reset(struct i2c_client *client)
398{
399	int error;
400
401	dev_dbg(&client->dev, "resetting device now\n");
402
403	error = wdt87xx_send_command(client, VND_CMD_RESET, 0);
404	if (error) {
405		dev_err(&client->dev, "reset failed\n");
406		return error;
407	}
408
409	/* Wait the device to be ready */
410	msleep(WDT_FW_RESET_TIME);
411
412	return 0;
413}
414
415static const void *wdt87xx_get_fw_chunk(const struct firmware *fw, u32 id)
416{
417	size_t pos = FW_PAYLOAD_OFFSET;
418	u32 chunk_id, chunk_size;
419
420	while (pos < fw->size) {
421		chunk_id = get_unaligned_le32(fw->data +
422					      pos + FW_CHUNK_ID_OFFSET);
423		if (chunk_id == id)
424			return fw->data + pos;
425
426		chunk_size = get_unaligned_le32(fw->data +
427						pos + FW_CHUNK_SIZE_OFFSET);
428		pos += chunk_size + 2 * sizeof(u32); /* chunk ID + size */
429	}
430
431	return NULL;
432}
433
434static int wdt87xx_get_sysparam(struct i2c_client *client,
435				struct wdt87xx_sys_param *param)
436{
437	u8 buf[PKT_READ_SIZE];
438	int error;
439
440	error = wdt87xx_get_desc(client, WDT_GD_DEVICE, buf, 18);
441	if (error) {
442		dev_err(&client->dev, "failed to get device desc\n");
443		return error;
444	}
445
446	param->vendor_id = get_unaligned_le16(buf + DEV_DESC_OFFSET_VID);
447	param->product_id = get_unaligned_le16(buf + DEV_DESC_OFFSET_PID);
448
449	error = wdt87xx_get_string(client, STRIDX_PARAMETERS, buf, 34);
450	if (error) {
451		dev_err(&client->dev, "failed to get parameters\n");
452		return error;
453	}
454
455	param->xmls_id1 = get_unaligned_le16(buf + CTL_PARAM_OFFSET_XMLS_ID1);
456	param->xmls_id2 = get_unaligned_le16(buf + CTL_PARAM_OFFSET_XMLS_ID2);
457	param->phy_ch_x = get_unaligned_le16(buf + CTL_PARAM_OFFSET_PHY_CH_X);
458	param->phy_ch_y = get_unaligned_le16(buf + CTL_PARAM_OFFSET_PHY_CH_Y);
459	param->phy_w = get_unaligned_le16(buf + CTL_PARAM_OFFSET_PHY_W) / 10;
460	param->phy_h = get_unaligned_le16(buf + CTL_PARAM_OFFSET_PHY_H) / 10;
461
462	/* Get the scaling factor of pixel to logical coordinate */
463	param->scaling_factor =
464			get_unaligned_le16(buf + CTL_PARAM_OFFSET_FACTOR);
465
466	param->max_x = MAX_UNIT_AXIS;
467	param->max_y = DIV_ROUND_CLOSEST(MAX_UNIT_AXIS * param->phy_h,
468					 param->phy_w);
469
470	error = wdt87xx_get_string(client, STRIDX_PLATFORM_ID, buf, 8);
471	if (error) {
472		dev_err(&client->dev, "failed to get platform id\n");
473		return error;
474	}
475
476	param->plat_id = buf[1];
477
478	buf[0] = 0xf2;
479	error = wdt87xx_get_feature(client, buf, 16);
480	if (error) {
481		dev_err(&client->dev, "failed to get firmware id\n");
482		return error;
483	}
484
485	if (buf[0] != 0xf2) {
486		dev_err(&client->dev, "wrong id of fw response: 0x%x\n",
487			buf[0]);
488		return -EINVAL;
489	}
490
491	param->fw_id = get_unaligned_le16(&buf[1]);
492
493	dev_info(&client->dev,
494		 "fw_id: 0x%x, plat_id: 0x%x, xml_id1: %04x, xml_id2: %04x\n",
495		 param->fw_id, param->plat_id,
496		 param->xmls_id1, param->xmls_id2);
497
498	return 0;
499}
500
501static int wdt87xx_validate_firmware(struct wdt87xx_data *wdt,
502				     const struct firmware *fw)
503{
504	const void *fw_chunk;
505	u32 data1, data2;
506	u32 size;
507	u8 fw_chip_id;
508	u8 chip_id;
509
510	data1 = get_unaligned_le32(fw->data + FW_FOURCC1_OFFSET);
511	data2 = get_unaligned_le32(fw->data + FW_FOURCC2_OFFSET);
512	if (data1 != FOURCC_ID_RIFF || data2 != FOURCC_ID_WHIF) {
513		dev_err(&wdt->client->dev, "check fw tag failed\n");
514		return -EINVAL;
515	}
516
517	size = get_unaligned_le32(fw->data + FW_SIZE_OFFSET);
518	if (size != fw->size) {
519		dev_err(&wdt->client->dev,
520			"fw size mismatch: expected %d, actual %zu\n",
521			size, fw->size);
522		return -EINVAL;
523	}
524
525	/*
526	 * Get the chip_id from the firmware. Make sure that it is the
527	 * right controller to do the firmware and config update.
528	 */
529	fw_chunk = wdt87xx_get_fw_chunk(fw, CHUNK_ID_FRWR);
530	if (!fw_chunk) {
531		dev_err(&wdt->client->dev,
532			"unable to locate firmware chunk\n");
533		return -EINVAL;
534	}
535
536	fw_chip_id = (get_unaligned_le32(fw_chunk +
537					 FW_CHUNK_VERSION_OFFSET) >> 12) & 0xF;
538	chip_id = (wdt->param.fw_id >> 12) & 0xF;
539
540	if (fw_chip_id != chip_id) {
541		dev_err(&wdt->client->dev,
542			"fw version mismatch: fw %d vs. chip %d\n",
543			fw_chip_id, chip_id);
544		return -ENODEV;
545	}
546
547	return 0;
548}
549
550static int wdt87xx_validate_fw_chunk(const void *data, int id)
551{
552	if (id == CHUNK_ID_FRWR) {
553		u32 fw_id;
554
555		fw_id = get_unaligned_le32(data + FW_CHUNK_PAYLOAD_OFFSET);
556		if (fw_id != WDT_FIRMWARE_ID)
557			return -EINVAL;
558	}
559
560	return 0;
561}
562
563static int wdt87xx_write_data(struct i2c_client *client, const char *data,
564			      u32 address, int length)
565{
566	u16 packet_size;
567	int count = 0;
568	int error;
569	u8 pkt_buf[PKT_BUF_SIZE];
570
571	/* Address and length should be 4 bytes aligned */
572	if ((address & 0x3) != 0 || (length & 0x3) != 0) {
573		dev_err(&client->dev,
574			"addr & len must be 4 bytes aligned %x, %x\n",
575			address, length);
576		return -EINVAL;
577	}
578
579	while (length) {
580		packet_size = min(length, PACKET_SIZE);
581
582		pkt_buf[CMD_REPORT_ID_OFFSET] = VND_REQ_WRITE;
583		pkt_buf[CMD_TYPE_OFFSET] = VND_SET_DATA;
584		put_unaligned_le16(packet_size, &pkt_buf[CMD_INDEX_OFFSET]);
585		put_unaligned_le32(address, &pkt_buf[CMD_LENGTH_OFFSET]);
586		memcpy(&pkt_buf[CMD_DATA_OFFSET], data, packet_size);
587
588		error = wdt87xx_set_feature(client, pkt_buf, sizeof(pkt_buf));
589		if (error)
590			return error;
591
592		length -= packet_size;
593		data += packet_size;
594		address += packet_size;
595
596		/* Wait for the controller to finish the write */
597		mdelay(WDT_FLASH_WRITE_DELAY_MS);
598
599		if ((++count % 32) == 0) {
600			/* Delay for fw to clear watch dog */
601			msleep(20);
602		}
603	}
604
605	return 0;
606}
607
608static u16 misr(u16 cur_value, u8 new_value)
609{
610	u32 a, b;
611	u32 bit0;
612	u32 y;
613
614	a = cur_value;
615	b = new_value;
616	bit0 = a ^ (b & 1);
617	bit0 ^= a >> 1;
618	bit0 ^= a >> 2;
619	bit0 ^= a >> 4;
620	bit0 ^= a >> 5;
621	bit0 ^= a >> 7;
622	bit0 ^= a >> 11;
623	bit0 ^= a >> 15;
624	y = (a << 1) ^ b;
625	y = (y & ~1) | (bit0 & 1);
626
627	return (u16)y;
628}
629
630static u16 wdt87xx_calculate_checksum(const u8 *data, size_t length)
631{
632	u16 checksum = 0;
633	size_t i;
634
635	for (i = 0; i < length; i++)
636		checksum = misr(checksum, data[i]);
637
638	return checksum;
639}
640
641static int wdt87xx_get_checksum(struct i2c_client *client, u16 *checksum,
642				u32 address, int length)
643{
644	int error;
645	int time_delay;
646	u8 pkt_buf[PKT_BUF_SIZE];
647	u8 cmd_buf[CMD_BUF_SIZE];
648
649	error = wdt87xx_send_command(client, VND_SET_CHECKSUM_LENGTH, length);
650	if (error) {
651		dev_err(&client->dev, "failed to set checksum length\n");
652		return error;
653	}
654
655	error = wdt87xx_send_command(client, VND_SET_CHECKSUM_CALC, address);
656	if (error) {
657		dev_err(&client->dev, "failed to set checksum address\n");
658		return error;
659	}
660
661	/* Wait the operation to complete */
662	time_delay = DIV_ROUND_UP(length, 1024);
663	msleep(time_delay * 30);
664
665	memset(cmd_buf, 0, sizeof(cmd_buf));
666	cmd_buf[CMD_REPORT_ID_OFFSET] = VND_REQ_READ;
667	cmd_buf[CMD_TYPE_OFFSET] = VND_GET_CHECKSUM;
668	error = wdt87xx_set_feature(client, cmd_buf, sizeof(cmd_buf));
669	if (error) {
670		dev_err(&client->dev, "failed to request checksum\n");
671		return error;
672	}
673
674	memset(pkt_buf, 0, sizeof(pkt_buf));
675	pkt_buf[CMD_REPORT_ID_OFFSET] = VND_READ_DATA;
676	error = wdt87xx_get_feature(client, pkt_buf, sizeof(pkt_buf));
677	if (error) {
678		dev_err(&client->dev, "failed to read checksum\n");
679		return error;
680	}
681
682	*checksum = get_unaligned_le16(&pkt_buf[CMD_DATA_OFFSET]);
683	return 0;
684}
685
686static int wdt87xx_write_firmware(struct i2c_client *client, const void *chunk)
687{
688	u32 start_addr = get_unaligned_le32(chunk + FW_CHUNK_TGT_START_OFFSET);
689	u32 size = get_unaligned_le32(chunk + FW_CHUNK_PAYLOAD_LEN_OFFSET);
690	const void *data = chunk + FW_CHUNK_PAYLOAD_OFFSET;
691	int error;
692	int err1;
693	int page_size;
694	int retry = 0;
695	u16 device_checksum, firmware_checksum;
696
697	dev_dbg(&client->dev, "start 4k page program\n");
698
699	error = wdt87xx_send_command(client, VND_CMD_STOP, MODE_STOP);
700	if (error) {
701		dev_err(&client->dev, "stop report mode failed\n");
702		return error;
703	}
704
705	error = wdt87xx_send_command(client, VND_CMD_SFUNL, 0);
706	if (error) {
707		dev_err(&client->dev, "unlock failed\n");
708		goto out_enable_reporting;
709	}
710
711	mdelay(10);
712
713	while (size) {
714		dev_dbg(&client->dev, "%s: %x, %x\n", __func__,
715			start_addr, size);
716
717		page_size = min_t(u32, size, PG_SIZE);
718		size -= page_size;
719
720		for (retry = 0; retry < MAX_RETRIES; retry++) {
721			error = wdt87xx_send_command(client, VND_CMD_ERASE,
722						     start_addr);
723			if (error) {
724				dev_err(&client->dev,
725					"erase failed at %#08x\n", start_addr);
726				break;
727			}
728
729			msleep(50);
730
731			error = wdt87xx_write_data(client, data, start_addr,
732						   page_size);
733			if (error) {
734				dev_err(&client->dev,
735					"write failed at %#08x (%d bytes)\n",
736					start_addr, page_size);
737				break;
738			}
739
740			error = wdt87xx_get_checksum(client, &device_checksum,
741						     start_addr, page_size);
742			if (error) {
743				dev_err(&client->dev,
744					"failed to retrieve checksum for %#08x (len: %d)\n",
745					start_addr, page_size);
746				break;
747			}
748
749			firmware_checksum =
750				wdt87xx_calculate_checksum(data, page_size);
751
752			if (device_checksum == firmware_checksum)
753				break;
754
755			dev_err(&client->dev,
756				"checksum fail: %d vs %d, retry %d\n",
757				device_checksum, firmware_checksum, retry);
758		}
759
760		if (retry == MAX_RETRIES) {
761			dev_err(&client->dev, "page write failed\n");
762			error = -EIO;
763			goto out_lock_device;
764		}
765
766		start_addr = start_addr + page_size;
767		data = data + page_size;
768	}
769
770out_lock_device:
771	err1 = wdt87xx_send_command(client, VND_CMD_SFLCK, 0);
772	if (err1)
773		dev_err(&client->dev, "lock failed\n");
774
775	mdelay(10);
776
777out_enable_reporting:
778	err1 = wdt87xx_send_command(client, VND_CMD_START, 0);
779	if (err1)
780		dev_err(&client->dev, "start to report failed\n");
781
782	return error ? error : err1;
783}
784
785static int wdt87xx_load_chunk(struct i2c_client *client,
786			      const struct firmware *fw, u32 ck_id)
787{
788	const void *chunk;
789	int error;
790
791	chunk = wdt87xx_get_fw_chunk(fw, ck_id);
792	if (!chunk) {
793		dev_err(&client->dev, "unable to locate chunk (type %d)\n",
794			ck_id);
795		return -EINVAL;
796	}
797
798	error = wdt87xx_validate_fw_chunk(chunk, ck_id);
799	if (error) {
800		dev_err(&client->dev, "invalid chunk (type %d): %d\n",
801			ck_id, error);
802		return error;
803	}
804
805	error = wdt87xx_write_firmware(client, chunk);
806	if (error) {
807		dev_err(&client->dev,
808			"failed to write fw chunk (type %d): %d\n",
809			ck_id, error);
810		return error;
811	}
812
813	return 0;
814}
815
816static int wdt87xx_do_update_firmware(struct i2c_client *client,
817				      const struct firmware *fw,
818				      unsigned int chunk_id)
819{
820	struct wdt87xx_data *wdt = i2c_get_clientdata(client);
821	int error;
822
823	error = wdt87xx_validate_firmware(wdt, fw);
824	if (error)
825		return error;
826
827	error = mutex_lock_interruptible(&wdt->fw_mutex);
828	if (error)
829		return error;
830
831	disable_irq(client->irq);
832
833	error = wdt87xx_load_chunk(client, fw, chunk_id);
834	if (error) {
835		dev_err(&client->dev,
836			"firmware load failed (type: %d): %d\n",
837			chunk_id, error);
838		goto out;
839	}
840
841	error = wdt87xx_sw_reset(client);
842	if (error) {
843		dev_err(&client->dev, "soft reset failed: %d\n", error);
844		goto out;
845	}
846
847	/* Refresh the parameters */
848	error = wdt87xx_get_sysparam(client, &wdt->param);
849	if (error)
850		dev_err(&client->dev,
851			"failed to refresh system paramaters: %d\n", error);
852out:
853	enable_irq(client->irq);
854	mutex_unlock(&wdt->fw_mutex);
855
856	return error ? error : 0;
857}
858
859static int wdt87xx_update_firmware(struct device *dev,
860				   const char *fw_name, unsigned int chunk_id)
861{
862	struct i2c_client *client = to_i2c_client(dev);
863	const struct firmware *fw;
864	int error;
865
866	error = request_firmware(&fw, fw_name, dev);
867	if (error) {
868		dev_err(&client->dev, "unable to retrieve firmware %s: %d\n",
869			fw_name, error);
870		return error;
871	}
872
873	error = wdt87xx_do_update_firmware(client, fw, chunk_id);
874
875	release_firmware(fw);
876
877	return error ? error : 0;
878}
879
880static ssize_t config_csum_show(struct device *dev,
881				struct device_attribute *attr, char *buf)
882{
883	struct i2c_client *client = to_i2c_client(dev);
884	struct wdt87xx_data *wdt = i2c_get_clientdata(client);
885	u32 cfg_csum;
886
887	cfg_csum = wdt->param.xmls_id1;
888	cfg_csum = (cfg_csum << 16) | wdt->param.xmls_id2;
889
890	return scnprintf(buf, PAGE_SIZE, "%x\n", cfg_csum);
891}
892
893static ssize_t fw_version_show(struct device *dev,
894			       struct device_attribute *attr, char *buf)
895{
896	struct i2c_client *client = to_i2c_client(dev);
897	struct wdt87xx_data *wdt = i2c_get_clientdata(client);
898
899	return scnprintf(buf, PAGE_SIZE, "%x\n", wdt->param.fw_id);
900}
901
902static ssize_t plat_id_show(struct device *dev,
903			    struct device_attribute *attr, char *buf)
904{
905	struct i2c_client *client = to_i2c_client(dev);
906	struct wdt87xx_data *wdt = i2c_get_clientdata(client);
907
908	return scnprintf(buf, PAGE_SIZE, "%x\n", wdt->param.plat_id);
909}
910
911static ssize_t update_config_store(struct device *dev,
912				   struct device_attribute *attr,
913				   const char *buf, size_t count)
914{
915	int error;
916
917	error = wdt87xx_update_firmware(dev, WDT87XX_CFG_NAME, CHUNK_ID_CNFG);
918
919	return error ? error : count;
920}
921
922static ssize_t update_fw_store(struct device *dev,
923			       struct device_attribute *attr,
924			       const char *buf, size_t count)
925{
926	int error;
927
928	error = wdt87xx_update_firmware(dev, WDT87XX_FW_NAME, CHUNK_ID_FRWR);
929
930	return error ? error : count;
931}
932
933static DEVICE_ATTR_RO(config_csum);
934static DEVICE_ATTR_RO(fw_version);
935static DEVICE_ATTR_RO(plat_id);
936static DEVICE_ATTR_WO(update_config);
937static DEVICE_ATTR_WO(update_fw);
938
939static struct attribute *wdt87xx_attrs[] = {
940	&dev_attr_config_csum.attr,
941	&dev_attr_fw_version.attr,
942	&dev_attr_plat_id.attr,
943	&dev_attr_update_config.attr,
944	&dev_attr_update_fw.attr,
945	NULL
946};
947
948static const struct attribute_group wdt87xx_attr_group = {
949	.attrs = wdt87xx_attrs,
950};
951
952static void wdt87xx_report_contact(struct input_dev *input,
953				   struct wdt87xx_sys_param *param,
954				   u8 *buf)
955{
956	int finger_id;
957	u32 x, y, w;
958	u8 p;
959
960	finger_id = (buf[FINGER_EV_V1_OFFSET_ID] >> 3) - 1;
961	if (finger_id < 0)
962		return;
963
964	/* Check if this is an active contact */
965	if (!(buf[FINGER_EV_V1_OFFSET_ID] & 0x1))
966		return;
967
968	w = buf[FINGER_EV_V1_OFFSET_W];
969	w *= param->scaling_factor;
970
971	p = buf[FINGER_EV_V1_OFFSET_P];
972
973	x = get_unaligned_le16(buf + FINGER_EV_V1_OFFSET_X);
974
975	y = get_unaligned_le16(buf + FINGER_EV_V1_OFFSET_Y);
976	y = DIV_ROUND_CLOSEST(y * param->phy_h, param->phy_w);
977
978	/* Refuse incorrect coordinates */
979	if (x > param->max_x || y > param->max_y)
980		return;
981
982	dev_dbg(input->dev.parent, "tip on (%d), x(%d), y(%d)\n",
983		finger_id, x, y);
984
985	input_mt_slot(input, finger_id);
986	input_mt_report_slot_state(input, MT_TOOL_FINGER, 1);
987	input_report_abs(input, ABS_MT_TOUCH_MAJOR, w);
988	input_report_abs(input, ABS_MT_PRESSURE, p);
989	input_report_abs(input, ABS_MT_POSITION_X, x);
990	input_report_abs(input, ABS_MT_POSITION_Y, y);
991}
992
993static irqreturn_t wdt87xx_ts_interrupt(int irq, void *dev_id)
994{
995	struct wdt87xx_data *wdt = dev_id;
996	struct i2c_client *client = wdt->client;
997	int i, fingers;
998	int error;
999	u8 raw_buf[WDT_V1_RAW_BUF_COUNT] = {0};
1000
1001	error = i2c_master_recv(client, raw_buf, WDT_V1_RAW_BUF_COUNT);
1002	if (error < 0) {
1003		dev_err(&client->dev, "read v1 raw data failed: %d\n", error);
1004		goto irq_exit;
1005	}
1006
1007	fingers = raw_buf[TOUCH_PK_V1_OFFSET_FNGR_NUM];
1008	if (!fingers)
1009		goto irq_exit;
1010
1011	for (i = 0; i < WDT_MAX_FINGER; i++)
1012		wdt87xx_report_contact(wdt->input,
1013				       &wdt->param,
1014				       &raw_buf[TOUCH_PK_V1_OFFSET_EVENT +
1015						i * FINGER_EV_V1_SIZE]);
1016
1017	input_mt_sync_frame(wdt->input);
1018	input_sync(wdt->input);
1019
1020irq_exit:
1021	return IRQ_HANDLED;
1022}
1023
1024static int wdt87xx_ts_create_input_device(struct wdt87xx_data *wdt)
1025{
1026	struct device *dev = &wdt->client->dev;
1027	struct input_dev *input;
1028	unsigned int res = DIV_ROUND_CLOSEST(MAX_UNIT_AXIS, wdt->param.phy_w);
1029	int error;
1030
1031	input = devm_input_allocate_device(dev);
1032	if (!input) {
1033		dev_err(dev, "failed to allocate input device\n");
1034		return -ENOMEM;
1035	}
1036	wdt->input = input;
1037
1038	input->name = "WDT87xx Touchscreen";
1039	input->id.bustype = BUS_I2C;
1040	input->id.vendor = wdt->param.vendor_id;
1041	input->id.product = wdt->param.product_id;
1042	input->phys = wdt->phys;
1043
1044	input_set_abs_params(input, ABS_MT_POSITION_X, 0,
1045			     wdt->param.max_x, 0, 0);
1046	input_set_abs_params(input, ABS_MT_POSITION_Y, 0,
1047			     wdt->param.max_y, 0, 0);
1048	input_abs_set_res(input, ABS_MT_POSITION_X, res);
1049	input_abs_set_res(input, ABS_MT_POSITION_Y, res);
1050
1051	input_set_abs_params(input, ABS_MT_TOUCH_MAJOR,
1052			     0, wdt->param.max_x, 0, 0);
1053	input_set_abs_params(input, ABS_MT_PRESSURE, 0, 0xFF, 0, 0);
1054
1055	input_mt_init_slots(input, WDT_MAX_FINGER,
1056			    INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
1057
1058	error = input_register_device(input);
1059	if (error) {
1060		dev_err(dev, "failed to register input device: %d\n", error);
1061		return error;
1062	}
1063
1064	return 0;
1065}
1066
1067static int wdt87xx_ts_probe(struct i2c_client *client,
1068			    const struct i2c_device_id *id)
1069{
1070	struct wdt87xx_data *wdt;
1071	int error;
1072
1073	dev_dbg(&client->dev, "adapter=%d, client irq: %d\n",
1074		client->adapter->nr, client->irq);
1075
1076	/* Check if the I2C function is ok in this adaptor */
1077	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
1078		return -ENXIO;
1079
1080	wdt = devm_kzalloc(&client->dev, sizeof(*wdt), GFP_KERNEL);
1081	if (!wdt)
1082		return -ENOMEM;
1083
1084	wdt->client = client;
1085	mutex_init(&wdt->fw_mutex);
1086	i2c_set_clientdata(client, wdt);
1087
1088	snprintf(wdt->phys, sizeof(wdt->phys), "i2c-%u-%04x/input0",
1089		 client->adapter->nr, client->addr);
1090
1091	error = wdt87xx_get_sysparam(client, &wdt->param);
1092	if (error)
1093		return error;
1094
1095	error = wdt87xx_ts_create_input_device(wdt);
1096	if (error)
1097		return error;
1098
1099	error = devm_request_threaded_irq(&client->dev, client->irq,
1100					  NULL, wdt87xx_ts_interrupt,
1101					  IRQF_ONESHOT,
1102					  client->name, wdt);
1103	if (error) {
1104		dev_err(&client->dev, "request irq failed: %d\n", error);
1105		return error;
1106	}
1107
1108	error = sysfs_create_group(&client->dev.kobj, &wdt87xx_attr_group);
1109	if (error) {
1110		dev_err(&client->dev, "create sysfs failed: %d\n", error);
1111		return error;
1112	}
1113
1114	return 0;
1115}
1116
1117static int wdt87xx_ts_remove(struct i2c_client *client)
1118{
1119	sysfs_remove_group(&client->dev.kobj, &wdt87xx_attr_group);
1120
1121	return 0;
1122}
1123
1124static int __maybe_unused wdt87xx_suspend(struct device *dev)
1125{
1126	struct i2c_client *client = to_i2c_client(dev);
1127	int error;
1128
1129	disable_irq(client->irq);
1130
1131	error = wdt87xx_send_command(client, VND_CMD_STOP, MODE_IDLE);
1132	if (error) {
1133		enable_irq(client->irq);
1134		dev_err(&client->dev,
1135			"failed to stop device when suspending: %d\n",
1136			error);
1137		return error;
1138	}
1139
1140	return 0;
1141}
1142
1143static int __maybe_unused wdt87xx_resume(struct device *dev)
1144{
1145	struct i2c_client *client = to_i2c_client(dev);
1146	int error;
1147
1148	/*
1149	 * The chip may have been reset while system is resuming,
1150	 * give it some time to settle.
1151	 */
1152	mdelay(100);
1153
1154	error = wdt87xx_send_command(client, VND_CMD_START, 0);
1155	if (error)
1156		dev_err(&client->dev,
1157			"failed to start device when resuming: %d\n",
1158			error);
1159
1160	enable_irq(client->irq);
1161
1162	return 0;
1163}
1164
1165static SIMPLE_DEV_PM_OPS(wdt87xx_pm_ops, wdt87xx_suspend, wdt87xx_resume);
1166
1167static const struct i2c_device_id wdt87xx_dev_id[] = {
1168	{ WDT87XX_NAME, 0 },
1169	{ }
1170};
1171MODULE_DEVICE_TABLE(i2c, wdt87xx_dev_id);
1172
1173static const struct acpi_device_id wdt87xx_acpi_id[] = {
1174	{ "WDHT0001", 0 },
1175	{ }
1176};
1177MODULE_DEVICE_TABLE(acpi, wdt87xx_acpi_id);
1178
1179static struct i2c_driver wdt87xx_driver = {
1180	.probe		= wdt87xx_ts_probe,
1181	.remove		= wdt87xx_ts_remove,
1182	.id_table	= wdt87xx_dev_id,
1183	.driver	= {
1184		.name	= WDT87XX_NAME,
1185		.pm     = &wdt87xx_pm_ops,
1186		.acpi_match_table = ACPI_PTR(wdt87xx_acpi_id),
1187	},
1188};
1189module_i2c_driver(wdt87xx_driver);
1190
1191MODULE_AUTHOR("HN Chen <hn.chen@weidahitech.com>");
1192MODULE_DESCRIPTION("WeidaHiTech WDT87XX Touchscreen driver");
1193MODULE_VERSION(WDT87XX_DRV_VER);
1194MODULE_LICENSE("GPL");
1195