summarylogtreecommitdiffstats
path: root/goodix_fwupload.c
blob: 191d4f38d991ec52493f66d4a0b4d474d1f8df38 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Goodix Touchscreen firmware upload support
 *
 * Copyright (c) 2021 Hans de Goede <hdegoede@redhat.com>
 *
 * This is a rewrite of gt9xx_update.c from the Allwinner H3 BSP which is:
 * Copyright (c) 2010 - 2012 Goodix Technology.
 * Author: andrew@goodix.com
 */

#include <linux/device.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include "goodix.h"

#define GOODIX_FW_HEADER_LENGTH		sizeof(struct goodix_fw_header)
#define GOODIX_FW_SECTION_LENGTH	0x2000
#define GOODIX_FW_DSP_LENGTH		0x1000
#define GOODIX_FW_UPLOAD_ADDRESS	0xc000

#define GOODIX_CFG_LOC_HAVE_KEY		 7
#define GOODIX_CFG_LOC_DRVA_NUM		27
#define GOODIX_CFG_LOC_DRVB_NUM		28
#define GOODIX_CFG_LOC_SENS_NUM		29

struct goodix_fw_header {
	u8 hw_info[4];
	u8 pid[8];
	u8 vid[2];
} __packed;

static u16 goodix_firmware_checksum(const u8 *data, int size)
{
	u16 checksum = 0;
	int i;

	for (i = 0; i < size; i += 2)
		checksum += (data[i] << 8) + data[i + 1];

	return checksum;
}

static int goodix_firmware_verify(struct device *dev, const struct firmware *fw)
{
	const struct goodix_fw_header *fw_header;
	size_t expected_size;
	const u8 *data;
	u16 checksum;
	char buf[9];

	expected_size = GOODIX_FW_HEADER_LENGTH + 4 * GOODIX_FW_SECTION_LENGTH +
			GOODIX_FW_DSP_LENGTH;
	if (fw->size != expected_size) {
		dev_err(dev, "Firmware has wrong size, expected %zu got %zu\n",
			expected_size, fw->size);
		return -EINVAL;
	}

	data = fw->data + GOODIX_FW_HEADER_LENGTH;
	checksum = goodix_firmware_checksum(data, 4 * GOODIX_FW_SECTION_LENGTH);
	if (checksum) {
		dev_err(dev, "Main firmware checksum error\n");
		return -EINVAL;
	}

	data += 4 * GOODIX_FW_SECTION_LENGTH;
	checksum = goodix_firmware_checksum(data, GOODIX_FW_DSP_LENGTH);
	if (checksum) {
		dev_err(dev, "DSP firmware checksum error\n");
		return -EINVAL;
	}

	fw_header = (const struct goodix_fw_header *)fw->data;
	dev_info(dev, "Firmware hardware info %02x%02x%02x%02x\n",
		 fw_header->hw_info[0], fw_header->hw_info[1],
		 fw_header->hw_info[2], fw_header->hw_info[3]);
	/* pid is a 8 byte buffer containing a string, weird I know */
	memcpy(buf, fw_header->pid, 8);
	buf[8] = 0;
	dev_info(dev, "Firmware PID: %s VID: %02x%02x\n", buf,
		 fw_header->vid[0], fw_header->vid[1]);
	return 0;
}

static int goodix_enter_upload_mode(struct i2c_client *client)
{
	int tries, error;
	u8 val;

	tries = 200;
	do {
		error = goodix_i2c_write_u8(client,
					    GOODIX_REG_MISCTL_SWRST, 0x0c);
		if (error)
			return error;

		error = goodix_i2c_read(client,
					GOODIX_REG_MISCTL_SWRST, &val, 1);
		if (error)
			return error;

		if (val == 0x0c)
			break;
	} while (--tries);

	if (!tries) {
		dev_err(&client->dev, "Error could not hold ss51 & dsp\n");
		return -EIO;
	}

	/* DSP_CK and DSP_ALU_CK PowerOn */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_DSP_CTL, 0x00);
	if (error)
		return error;

	/* Disable watchdog */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_TMR0_EN, 0x00);
	if (error)
		return error;

	/* Clear cache enable */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_CACHE_EN, 0x00);
	if (error)
		return error;

	/* Set boot from SRAM */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_BOOTCTL, 0x02);
	if (error)
		return error;

	/* Software reboot */
	error = goodix_i2c_write_u8(client,
				    GOODIX_REG_MISCTL_CPU_SWRST_PULSE, 0x01);
	if (error)
		return error;

	/* Clear control flag */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_BOOTCTL, 0x00);
	if (error)
		return error;

	/* Set scramble */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_BOOT_OPT, 0x00);
	if (error)
		return error;

	/* Enable accessing code */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_MEM_CD_EN, 0x01);
	if (error)
		return error;

	return 0;
}

static int goodix_start_firmware(struct i2c_client *client)
{
	int error;
	u8 val;

	/* Init software watchdog */
	error = goodix_i2c_write_u8(client, GOODIX_REG_SW_WDT, 0xaa);
	if (error)
		return error;

	/* Release SS51 & DSP */
	error = goodix_i2c_write_u8(client, GOODIX_REG_MISCTL_SWRST, 0x00);
	if (error)
		return error;

	error = goodix_i2c_read(client, GOODIX_REG_SW_WDT, &val, 1);
	if (error)
		return error;

	/* The value we've written to SW_WDT should have been cleared now */
	if (val == 0xaa) {
		dev_err(&client->dev, "Error SW_WDT reg not cleared on fw startup\n");
		return -EIO;
	}

	/* Re-init software watchdog */
	error = goodix_i2c_write_u8(client, GOODIX_REG_SW_WDT, 0xaa);
	if (error)
		return error;

	return 0;
}

static int goodix_firmware_upload(struct goodix_ts_data *ts)
{
	const struct firmware *fw;
	char fw_name[64];
	const u8 *data;
	int error;

	snprintf(fw_name, sizeof(fw_name), "goodix/%s", ts->firmware_name);

	error = request_firmware(&fw, fw_name, &ts->client->dev);
	if (error) {
		dev_err(&ts->client->dev, "Firmware request error %d\n", error);
		return error;
	}

	error = goodix_firmware_verify(&ts->client->dev, fw);
	if (error)
		goto release;

	error = goodix_reset_no_int_sync(ts);
	if (error)
		goto release;

	error = goodix_enter_upload_mode(ts->client);
	if (error)
		goto release;

	/* Select SRAM bank 0 and upload section 1 & 2 */
	error = goodix_i2c_write_u8(ts->client,
				    GOODIX_REG_MISCTL_SRAM_BANK, 0x00);
	if (error)
		goto release;

	data = fw->data + GOODIX_FW_HEADER_LENGTH;
	error = goodix_i2c_write(ts->client, GOODIX_FW_UPLOAD_ADDRESS,
				 data, 2 * GOODIX_FW_SECTION_LENGTH);
	if (error)
		goto release;

	/* Select SRAM bank 1 and upload section 3 & 4 */
	error = goodix_i2c_write_u8(ts->client,
				    GOODIX_REG_MISCTL_SRAM_BANK, 0x01);
	if (error)
		goto release;

	data += 2 * GOODIX_FW_SECTION_LENGTH;
	error = goodix_i2c_write(ts->client, GOODIX_FW_UPLOAD_ADDRESS,
				 data, 2 * GOODIX_FW_SECTION_LENGTH);
	if (error)
		goto release;

	/* Select SRAM bank 2 and upload the DSP firmware */
	error = goodix_i2c_write_u8(ts->client,
				    GOODIX_REG_MISCTL_SRAM_BANK, 0x02);
	if (error)
		goto release;

	data += 2 * GOODIX_FW_SECTION_LENGTH;
	error = goodix_i2c_write(ts->client, GOODIX_FW_UPLOAD_ADDRESS,
				 data, GOODIX_FW_DSP_LENGTH);
	if (error)
		goto release;

	error = goodix_start_firmware(ts->client);
	if (error)
		goto release;

	error = goodix_int_sync(ts);
release:
	release_firmware(fw);
	return error;
}

static int goodix_prepare_bak_ref(struct goodix_ts_data *ts)
{
	u8 have_key, driver_num, sensor_num;

	if (ts->bak_ref)
		return 0; /* Already done */

	have_key = (ts->config[GOODIX_CFG_LOC_HAVE_KEY] & 0x01);

	driver_num = (ts->config[GOODIX_CFG_LOC_DRVA_NUM] & 0x1f) +
		     (ts->config[GOODIX_CFG_LOC_DRVB_NUM] & 0x1f);
	if (have_key)
		driver_num--;

	sensor_num = (ts->config[GOODIX_CFG_LOC_SENS_NUM] & 0x0f) +
		     ((ts->config[GOODIX_CFG_LOC_SENS_NUM] >> 4) & 0x0f);

	dev_dbg(&ts->client->dev, "Drv %d Sen %d Key %d\n",
		driver_num, sensor_num, have_key);

	ts->bak_ref_len = (driver_num * (sensor_num - 2) + 2) * 2;

	ts->bak_ref = devm_kzalloc(&ts->client->dev,
				   ts->bak_ref_len, GFP_KERNEL);
	if (!ts->bak_ref)
		return -ENOMEM;

	/*
	 * The bak_ref array contains the backup of an array of (self/auto)
	 * calibration related values which the Android version of the driver
	 * stores on the filesystem so that it can be restored after reboot.
	 * The mainline kernel never writes directly to the filesystem like
	 * this, we always start will all the values which give a correction
	 * factor in approx. the -20 - +20 range (in 2s complement) set to 0.
	 *
	 * Note the touchscreen works fine without restoring the reference
	 * values after a reboot / power-cycle.
	 *
	 * The last 2 bytes are a 16 bits unsigned checksum which is expected
	 * to make the addition al all 16 bit unsigned values in the array add
	 * up to 1 (rather then the usual 0), so we must set the last byte to 1.
	 */
	ts->bak_ref[ts->bak_ref_len - 1] = 1;

	return 0;
}

static int goodix_send_main_clock(struct goodix_ts_data *ts)
{
	u32 main_clk = 54; /* Default main clock */
	u8 checksum = 0;
	int i;

	device_property_read_u32(&ts->client->dev,
				 "goodix,main-clk", &main_clk);

	for (i = 0; i < (GOODIX_MAIN_CLK_LEN - 1); i++) {
		ts->main_clk[i] = main_clk;
		checksum += main_clk;
	}

	/* The value of all bytes combines must be 0 */
	ts->main_clk[GOODIX_MAIN_CLK_LEN - 1] = 256 - checksum;

	return goodix_i2c_write(ts->client, GOODIX_REG_MAIN_CLK,
				ts->main_clk, GOODIX_MAIN_CLK_LEN);
}

int goodix_firmware_check(struct goodix_ts_data *ts)
{
	device_property_read_string(&ts->client->dev,
				    "firmware-name", &ts->firmware_name);
	if (!ts->firmware_name)
		return 0;

	if (ts->irq_pin_access_method == IRQ_PIN_ACCESS_NONE) {
		dev_err(&ts->client->dev, "Error no IRQ-pin access method, cannot upload fw.\n");
		return -EINVAL;
	}

	dev_info(&ts->client->dev, "Touchscreen controller needs fw-upload\n");
	ts->load_cfg_from_disk = true;

	return goodix_firmware_upload(ts);
}

bool goodix_handle_fw_request(struct goodix_ts_data *ts)
{
	int error;
	u8 val;

	error = goodix_i2c_read(ts->client, GOODIX_REG_REQUEST, &val, 1);
	if (error)
		return false;

	switch (val) {
	case GOODIX_RQST_RESPONDED:
		/*
		 * If we read back our own last ack the IRQ was not for
		 * a request.
		 */
		return false;
	case GOODIX_RQST_CONFIG:
		error = goodix_send_cfg(ts, ts->config, ts->chip->config_len);
		if (error)
			return false;

		break;
	case GOODIX_RQST_BAK_REF:
		error = goodix_prepare_bak_ref(ts);
		if (error)
			return false;

		error = goodix_i2c_write(ts->client, GOODIX_REG_BAK_REF,
					 ts->bak_ref, ts->bak_ref_len);
		if (error)
			return false;

		break;
	case GOODIX_RQST_RESET:
		error = goodix_firmware_upload(ts);
		if (error)
			return false;

		break;
	case GOODIX_RQST_MAIN_CLOCK:
		error = goodix_send_main_clock(ts);
		if (error)
			return false;

		break;
	case GOODIX_RQST_UNKNOWN:
	case GOODIX_RQST_IDLE:
		break;
	default:
		dev_err_ratelimited(&ts->client->dev, "Unknown Request: 0x%02x\n", val);
	}

	/* Ack the request */
	goodix_i2c_write_u8(ts->client,
			    GOODIX_REG_REQUEST, GOODIX_RQST_RESPONDED);
	return true;
}

void goodix_save_bak_ref(struct goodix_ts_data *ts)
{
	int error;
	u8 val;

	if (!ts->firmware_name)
		return;

	error = goodix_i2c_read(ts->client, GOODIX_REG_STATUS, &val, 1);
	if (error)
		return;

	if (!(val & 0x80))
		return;

	error = goodix_i2c_read(ts->client, GOODIX_REG_BAK_REF,
				ts->bak_ref, ts->bak_ref_len);
	if (error) {
		memset(ts->bak_ref, 0, ts->bak_ref_len);
		ts->bak_ref[ts->bak_ref_len - 1] = 1;
	}
}