summaryrefslogtreecommitdiffstats
path: root/drivers/leds/leds-lp5523.c
blob: 365e9148e5e8fefd28499c3117a3ead57ee5ed90 (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
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
/*
 * lp5523.c - LP5523 LED Driver
 *
 * Copyright (C) 2010 Nokia Corporation
 * Copyright (C) 2012 Texas Instruments
 *
 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
 *          Milo(Woogyom) Kim <milo.kim@ti.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA
 */

#include <linux/delay.h>
#include <linux/firmware.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>

#include "leds-lp55xx-common.h"

#define LP5523_PROGRAM_LENGTH		32
#define LP5523_MAX_LEDS			9

/* Registers */
#define LP5523_REG_ENABLE		0x00
#define LP5523_REG_OP_MODE		0x01
#define LP5523_REG_ENABLE_LEDS_MSB	0x04
#define LP5523_REG_ENABLE_LEDS_LSB	0x05
#define LP5523_REG_LED_PWM_BASE		0x16
#define LP5523_REG_LED_CURRENT_BASE	0x26
#define LP5523_REG_CONFIG		0x36
#define LP5523_REG_STATUS		0x3A
#define LP5523_REG_RESET		0x3D
#define LP5523_REG_LED_TEST_CTRL	0x41
#define LP5523_REG_LED_TEST_ADC		0x42
#define LP5523_REG_PROG_PAGE_SEL	0x4F
#define LP5523_REG_PROG_MEM		0x50

/* Bit description in registers */
#define LP5523_ENABLE			0x40
#define LP5523_AUTO_INC			0x40
#define LP5523_PWR_SAVE			0x20
#define LP5523_PWM_PWR_SAVE		0x04
#define LP5523_CP_AUTO			0x18
#define LP5523_AUTO_CLK			0x02

#define LP5523_EN_LEDTEST		0x80
#define LP5523_LEDTEST_DONE		0x80
#define LP5523_RESET			0xFF
#define LP5523_ADC_SHORTCIRC_LIM	80
#define LP5523_EXT_CLK_USED		0x08

/* Memory Page Selection */
#define LP5523_PAGE_ENG1		0
#define LP5523_PAGE_ENG2		1
#define LP5523_PAGE_ENG3		2

/* Program Memory Operations */
#define LP5523_MODE_ENG1_M		0x30	/* Operation Mode Register */
#define LP5523_MODE_ENG2_M		0x0C
#define LP5523_MODE_ENG3_M		0x03
#define LP5523_LOAD_ENG1		0x10
#define LP5523_LOAD_ENG2		0x04
#define LP5523_LOAD_ENG3		0x01

#define LP5523_ENG1_IS_LOADING(mode)	\
	((mode & LP5523_MODE_ENG1_M) == LP5523_LOAD_ENG1)
#define LP5523_ENG2_IS_LOADING(mode)	\
	((mode & LP5523_MODE_ENG2_M) == LP5523_LOAD_ENG2)
#define LP5523_ENG3_IS_LOADING(mode)	\
	((mode & LP5523_MODE_ENG3_M) == LP5523_LOAD_ENG3)

#define LP5523_EXEC_ENG1_M		0x30	/* Enable Register */
#define LP5523_EXEC_ENG2_M		0x0C
#define LP5523_EXEC_ENG3_M		0x03
#define LP5523_EXEC_M			0x3F
#define LP5523_RUN_ENG1			0x20
#define LP5523_RUN_ENG2			0x08
#define LP5523_RUN_ENG3			0x02

enum lp5523_chip_id {
	LP5523,
	LP55231,
};

static inline void lp5523_wait_opmode_done(void)
{
	usleep_range(1000, 2000);
}

static void lp5523_set_led_current(struct lp55xx_led *led, u8 led_current)
{
	led->led_current = led_current;
	lp55xx_write(led->chip, LP5523_REG_LED_CURRENT_BASE + led->chan_nr,
		led_current);
}

static int lp5523_post_init_device(struct lp55xx_chip *chip)
{
	int ret;

	ret = lp55xx_write(chip, LP5523_REG_ENABLE, LP5523_ENABLE);
	if (ret)
		return ret;

	/* Chip startup time is 500 us, 1 - 2 ms gives some margin */
	usleep_range(1000, 2000);

	ret = lp55xx_write(chip, LP5523_REG_CONFIG,
			    LP5523_AUTO_INC | LP5523_PWR_SAVE |
			    LP5523_CP_AUTO | LP5523_AUTO_CLK |
			    LP5523_PWM_PWR_SAVE);
	if (ret)
		return ret;

	/* turn on all leds */
	ret = lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_MSB, 0x01);
	if (ret)
		return ret;

	return lp55xx_write(chip, LP5523_REG_ENABLE_LEDS_LSB, 0xff);
}

static void lp5523_load_engine(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	u8 mask[] = {
		[LP55XX_ENGINE_1] = LP5523_MODE_ENG1_M,
		[LP55XX_ENGINE_2] = LP5523_MODE_ENG2_M,
		[LP55XX_ENGINE_3] = LP5523_MODE_ENG3_M,
	};

	u8 val[] = {
		[LP55XX_ENGINE_1] = LP5523_LOAD_ENG1,
		[LP55XX_ENGINE_2] = LP5523_LOAD_ENG2,
		[LP55XX_ENGINE_3] = LP5523_LOAD_ENG3,
	};

	u8 page_sel[] = {
		[LP55XX_ENGINE_1] = LP5523_PAGE_ENG1,
		[LP55XX_ENGINE_2] = LP5523_PAGE_ENG2,
		[LP55XX_ENGINE_3] = LP5523_PAGE_ENG3,
	};

	lp55xx_update_bits(chip, LP5523_REG_OP_MODE, mask[idx], val[idx]);

	lp5523_wait_opmode_done();

	lp55xx_write(chip, LP5523_REG_PROG_PAGE_SEL, page_sel[idx]);
}

static void lp5523_stop_engine(struct lp55xx_chip *chip)
{
	lp55xx_write(chip, LP5523_REG_OP_MODE, 0);
	lp5523_wait_opmode_done();
}

static void lp5523_turn_off_channels(struct lp55xx_chip *chip)
{
	int i;

	for (i = 0; i < LP5523_MAX_LEDS; i++)
		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0);
}

static void lp5523_run_engine(struct lp55xx_chip *chip, bool start)
{
	int ret;
	u8 mode;
	u8 exec;

	/* stop engine */
	if (!start) {
		lp5523_stop_engine(chip);
		lp5523_turn_off_channels(chip);
		return;
	}

	/*
	 * To run the engine,
	 * operation mode and enable register should updated at the same time
	 */

	ret = lp55xx_read(chip, LP5523_REG_OP_MODE, &mode);
	if (ret)
		return;

	ret = lp55xx_read(chip, LP5523_REG_ENABLE, &exec);
	if (ret)
		return;

	/* change operation mode to RUN only when each engine is loading */
	if (LP5523_ENG1_IS_LOADING(mode)) {
		mode = (mode & ~LP5523_MODE_ENG1_M) | LP5523_RUN_ENG1;
		exec = (exec & ~LP5523_EXEC_ENG1_M) | LP5523_RUN_ENG1;
	}

	if (LP5523_ENG2_IS_LOADING(mode)) {
		mode = (mode & ~LP5523_MODE_ENG2_M) | LP5523_RUN_ENG2;
		exec = (exec & ~LP5523_EXEC_ENG2_M) | LP5523_RUN_ENG2;
	}

	if (LP5523_ENG3_IS_LOADING(mode)) {
		mode = (mode & ~LP5523_MODE_ENG3_M) | LP5523_RUN_ENG3;
		exec = (exec & ~LP5523_EXEC_ENG3_M) | LP5523_RUN_ENG3;
	}

	lp55xx_write(chip, LP5523_REG_OP_MODE, mode);
	lp5523_wait_opmode_done();

	lp55xx_update_bits(chip, LP5523_REG_ENABLE, LP5523_EXEC_M, exec);
}

static int lp5523_update_program_memory(struct lp55xx_chip *chip,
					const u8 *data, size_t size)
{
	u8 pattern[LP5523_PROGRAM_LENGTH] = {0};
	unsigned cmd;
	char c[3];
	int update_size;
	int nrchars;
	int offset = 0;
	int ret;
	int i;

	/* clear program memory before updating */
	for (i = 0; i < LP5523_PROGRAM_LENGTH; i++)
		lp55xx_write(chip, LP5523_REG_PROG_MEM + i, 0);

	i = 0;
	while ((offset < size - 1) && (i < LP5523_PROGRAM_LENGTH)) {
		/* separate sscanfs because length is working only for %s */
		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
		if (ret != 1)
			goto err;

		ret = sscanf(c, "%2x", &cmd);
		if (ret != 1)
			goto err;

		pattern[i] = (u8)cmd;
		offset += nrchars;
		i++;
	}

	/* Each instruction is 16bit long. Check that length is even */
	if (i % 2)
		goto err;

	update_size = i;
	for (i = 0; i < update_size; i++)
		lp55xx_write(chip, LP5523_REG_PROG_MEM + i, pattern[i]);

	return 0;

err:
	dev_err(&chip->cl->dev, "wrong pattern format\n");
	return -EINVAL;
}

static void lp5523_firmware_loaded(struct lp55xx_chip *chip)
{
	const struct firmware *fw = chip->fw;

	if (fw->size > LP5523_PROGRAM_LENGTH) {
		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
			fw->size);
		return;
	}

	/*
	 * Program momery sequence
	 *  1) set engine mode to "LOAD"
	 *  2) write firmware data into program memory
	 */

	lp5523_load_engine(chip);
	lp5523_update_program_memory(chip, fw->data, fw->size);
}

static ssize_t lp5523_selftest(struct device *dev,
			       struct device_attribute *attr,
			       char *buf)
{
	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
	struct lp55xx_chip *chip = led->chip;
	struct lp55xx_platform_data *pdata = chip->pdata;
	int i, ret, pos = 0;
	u8 status, adc, vdd;

	mutex_lock(&chip->lock);

	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
	if (ret < 0)
		goto fail;

	/* Check that ext clock is really in use if requested */
	if (pdata->clock_mode == LP55XX_CLOCK_EXT) {
		if  ((status & LP5523_EXT_CLK_USED) == 0)
			goto fail;
	}

	/* Measure VDD (i.e. VBAT) first (channel 16 corresponds to VDD) */
	lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL, LP5523_EN_LEDTEST | 16);
	usleep_range(3000, 6000); /* ADC conversion time is typically 2.7 ms */
	ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
	if (ret < 0)
		goto fail;

	if (!(status & LP5523_LEDTEST_DONE))
		usleep_range(3000, 6000); /* Was not ready. Wait little bit */

	ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &vdd);
	if (ret < 0)
		goto fail;

	vdd--;	/* There may be some fluctuation in measurement */

	for (i = 0; i < LP5523_MAX_LEDS; i++) {
		/* Skip non-existing channels */
		if (pdata->led_config[i].led_current == 0)
			continue;

		/* Set default current */
		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
			pdata->led_config[i].led_current);

		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0xff);
		/* let current stabilize 2 - 4ms before measurements start */
		usleep_range(2000, 4000);
		lp55xx_write(chip, LP5523_REG_LED_TEST_CTRL,
			     LP5523_EN_LEDTEST | i);
		/* ADC conversion time is 2.7 ms typically */
		usleep_range(3000, 6000);
		ret = lp55xx_read(chip, LP5523_REG_STATUS, &status);
		if (ret < 0)
			goto fail;

		if (!(status & LP5523_LEDTEST_DONE))
			usleep_range(3000, 6000);/* Was not ready. Wait. */

		ret = lp55xx_read(chip, LP5523_REG_LED_TEST_ADC, &adc);
		if (ret < 0)
			goto fail;

		if (adc >= vdd || adc < LP5523_ADC_SHORTCIRC_LIM)
			pos += sprintf(buf + pos, "LED %d FAIL\n", i);

		lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + i, 0x00);

		/* Restore current */
		lp55xx_write(chip, LP5523_REG_LED_CURRENT_BASE + i,
			led->led_current);
		led++;
	}
	if (pos == 0)
		pos = sprintf(buf, "OK\n");
	goto release_lock;
fail:
	pos = sprintf(buf, "FAIL\n");

release_lock:
	mutex_unlock(&chip->lock);

	return pos;
}

static void lp5523_led_brightness_work(struct work_struct *work)
{
	struct lp55xx_led *led = container_of(work, struct lp55xx_led,
					      brightness_work);
	struct lp55xx_chip *chip = led->chip;

	mutex_lock(&chip->lock);
	lp55xx_write(chip, LP5523_REG_LED_PWM_BASE + led->chan_nr,
		     led->brightness);
	mutex_unlock(&chip->lock);
}

static DEVICE_ATTR(selftest, S_IRUGO, lp5523_selftest, NULL);

static struct attribute *lp5523_attributes[] = {
	&dev_attr_selftest.attr,
	NULL,
};

static const struct attribute_group lp5523_group = {
	.attrs = lp5523_attributes,
};

/* Chip specific configurations */
static struct lp55xx_device_config lp5523_cfg = {
	.reset = {
		.addr = LP5523_REG_RESET,
		.val  = LP5523_RESET,
	},
	.enable = {
		.addr = LP5523_REG_ENABLE,
		.val  = LP5523_ENABLE,
	},
	.max_channel  = LP5523_MAX_LEDS,
	.post_init_device   = lp5523_post_init_device,
	.brightness_work_fn = lp5523_led_brightness_work,
	.set_led_current    = lp5523_set_led_current,
	.firmware_cb        = lp5523_firmware_loaded,
	.run_engine         = lp5523_run_engine,
	.dev_attr_group     = &lp5523_group,
};

static int lp5523_probe(struct i2c_client *client,
			const struct i2c_device_id *id)
{
	int ret;
	struct lp55xx_chip *chip;
	struct lp55xx_led *led;
	struct lp55xx_platform_data *pdata;
	struct device_node *np = client->dev.of_node;

	if (!client->dev.platform_data) {
		if (np) {
			ret = lp55xx_of_populate_pdata(&client->dev, np);
			if (ret < 0)
				return ret;
		} else {
			dev_err(&client->dev, "no platform data\n");
			return -EINVAL;
		}
	}
	pdata = client->dev.platform_data;

	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
	if (!chip)
		return -ENOMEM;

	led = devm_kzalloc(&client->dev,
			sizeof(*led) * pdata->num_channels, GFP_KERNEL);
	if (!led)
		return -ENOMEM;

	chip->cl = client;
	chip->pdata = pdata;
	chip->cfg = &lp5523_cfg;

	mutex_init(&chip->lock);

	i2c_set_clientdata(client, led);

	ret = lp55xx_init_device(chip);
	if (ret)
		goto err_init;

	dev_info(&client->dev, "%s Programmable led chip found\n", id->name);

	ret = lp55xx_register_leds(led, chip);
	if (ret)
		goto err_register_leds;

	ret = lp55xx_register_sysfs(chip);
	if (ret) {
		dev_err(&client->dev, "registering sysfs failed\n");
		goto err_register_sysfs;
	}

	return 0;

err_register_sysfs:
	lp55xx_unregister_leds(led, chip);
err_register_leds:
	lp55xx_deinit_device(chip);
err_init:
	return ret;
}

static int lp5523_remove(struct i2c_client *client)
{
	struct lp55xx_led *led = i2c_get_clientdata(client);
	struct lp55xx_chip *chip = led->chip;

	lp5523_stop_engine(chip);
	lp55xx_unregister_sysfs(chip);
	lp55xx_unregister_leds(led, chip);
	lp55xx_deinit_device(chip);

	return 0;
}

static const struct i2c_device_id lp5523_id[] = {
	{ "lp5523",  LP5523 },
	{ "lp55231", LP55231 },
	{ "national,lp5523", 0 }, /* OF compatible */
	{ }
};

MODULE_DEVICE_TABLE(i2c, lp5523_id);

static struct i2c_driver lp5523_driver = {
	.driver = {
		.name	= "lp5523x",
	},
	.probe		= lp5523_probe,
	.remove		= lp5523_remove,
	.id_table	= lp5523_id,
};

module_i2c_driver(lp5523_driver);

MODULE_AUTHOR("Mathias Nyman <mathias.nyman@nokia.com>");
MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
MODULE_DESCRIPTION("LP5523 LED engine");
MODULE_LICENSE("GPL");