summaryrefslogtreecommitdiff
path: root/drivers/leds/leds-lp8501.c
blob: 00f068b0fa6f0610886d851fdfc907a759326779 (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
/*
 * TI LP8501 9 channel LED Driver
 *
 * Copyright (C) 2013 Texas Instruments
 *
 * Author: 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.
 *
 */

#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/of.h>
#include <linux/platform_data/leds-lp55xx.h>
#include <linux/slab.h>

#include "leds-lp55xx-common.h"

#define LP8501_PROGRAM_LENGTH		32
#define LP8501_MAX_LEDS			9

/* Registers */
#define LP8501_REG_ENABLE		0x00
#define LP8501_ENABLE			BIT(6)
#define LP8501_EXEC_M			0x3F
#define LP8501_EXEC_ENG1_M		0x30
#define LP8501_EXEC_ENG2_M		0x0C
#define LP8501_EXEC_ENG3_M		0x03
#define LP8501_RUN_ENG1			0x20
#define LP8501_RUN_ENG2			0x08
#define LP8501_RUN_ENG3			0x02

#define LP8501_REG_OP_MODE		0x01
#define LP8501_MODE_ENG1_M		0x30
#define LP8501_MODE_ENG2_M		0x0C
#define LP8501_MODE_ENG3_M		0x03
#define LP8501_LOAD_ENG1		0x10
#define LP8501_LOAD_ENG2		0x04
#define LP8501_LOAD_ENG3		0x01

#define LP8501_REG_PWR_CONFIG		0x05
#define LP8501_PWR_CONFIG_M		0x03

#define LP8501_REG_LED_PWM_BASE		0x16

#define LP8501_REG_LED_CURRENT_BASE	0x26

#define LP8501_REG_CONFIG		0x36
#define LP8501_PWM_PSAVE		BIT(7)
#define LP8501_AUTO_INC			BIT(6)
#define LP8501_PWR_SAVE			BIT(5)
#define LP8501_CP_AUTO			0x18
#define LP8501_INT_CLK			BIT(0)
#define LP8501_DEFAULT_CFG	\
	(LP8501_PWM_PSAVE | LP8501_AUTO_INC | LP8501_PWR_SAVE | LP8501_CP_AUTO)

#define LP8501_REG_RESET		0x3D
#define LP8501_RESET			0xFF

#define LP8501_REG_PROG_PAGE_SEL	0x4F
#define LP8501_PAGE_ENG1		0
#define LP8501_PAGE_ENG2		1
#define LP8501_PAGE_ENG3		2

#define LP8501_REG_PROG_MEM		0x50

#define LP8501_ENG1_IS_LOADING(mode)	\
	((mode & LP8501_MODE_ENG1_M) == LP8501_LOAD_ENG1)
#define LP8501_ENG2_IS_LOADING(mode)	\
	((mode & LP8501_MODE_ENG2_M) == LP8501_LOAD_ENG2)
#define LP8501_ENG3_IS_LOADING(mode)	\
	((mode & LP8501_MODE_ENG3_M) == LP8501_LOAD_ENG3)

static inline void lp8501_wait_opmode_done(void)
{
	usleep_range(1000, 2000);
}

static void lp8501_set_led_current(struct lp55xx_led *led, u8 led_current)
{
	led->led_current = led_current;
	lp55xx_write(led->chip, LP8501_REG_LED_CURRENT_BASE + led->chan_nr,
		led_current);
}

static int lp8501_post_init_device(struct lp55xx_chip *chip)
{
	int ret;
	u8 val = LP8501_DEFAULT_CFG;

	ret = lp55xx_write(chip, LP8501_REG_ENABLE, LP8501_ENABLE);
	if (ret)
		return ret;

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

	if (chip->pdata->clock_mode != LP55XX_CLOCK_EXT)
		val |= LP8501_INT_CLK;

	ret = lp55xx_write(chip, LP8501_REG_CONFIG, val);
	if (ret)
		return ret;

	/* Power selection for each output */
	return lp55xx_update_bits(chip, LP8501_REG_PWR_CONFIG,
				LP8501_PWR_CONFIG_M, chip->pdata->pwr_sel);
}

static void lp8501_load_engine(struct lp55xx_chip *chip)
{
	enum lp55xx_engine_index idx = chip->engine_idx;
	u8 mask[] = {
		[LP55XX_ENGINE_1] = LP8501_MODE_ENG1_M,
		[LP55XX_ENGINE_2] = LP8501_MODE_ENG2_M,
		[LP55XX_ENGINE_3] = LP8501_MODE_ENG3_M,
	};

	u8 val[] = {
		[LP55XX_ENGINE_1] = LP8501_LOAD_ENG1,
		[LP55XX_ENGINE_2] = LP8501_LOAD_ENG2,
		[LP55XX_ENGINE_3] = LP8501_LOAD_ENG3,
	};

	u8 page_sel[] = {
		[LP55XX_ENGINE_1] = LP8501_PAGE_ENG1,
		[LP55XX_ENGINE_2] = LP8501_PAGE_ENG2,
		[LP55XX_ENGINE_3] = LP8501_PAGE_ENG3,
	};

	lp55xx_update_bits(chip, LP8501_REG_OP_MODE, mask[idx], val[idx]);

	lp8501_wait_opmode_done();

	lp55xx_write(chip, LP8501_REG_PROG_PAGE_SEL, page_sel[idx]);
}

static void lp8501_stop_engine(struct lp55xx_chip *chip)
{
	lp55xx_write(chip, LP8501_REG_OP_MODE, 0);
	lp8501_wait_opmode_done();
}

static void lp8501_turn_off_channels(struct lp55xx_chip *chip)
{
	int i;

	for (i = 0; i < LP8501_MAX_LEDS; i++)
		lp55xx_write(chip, LP8501_REG_LED_PWM_BASE + i, 0);
}

static void lp8501_run_engine(struct lp55xx_chip *chip, bool start)
{
	int ret;
	u8 mode;
	u8 exec;

	/* stop engine */
	if (!start) {
		lp8501_stop_engine(chip);
		lp8501_turn_off_channels(chip);
		return;
	}

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

	ret = lp55xx_read(chip, LP8501_REG_OP_MODE, &mode);
	if (ret)
		return;

	ret = lp55xx_read(chip, LP8501_REG_ENABLE, &exec);
	if (ret)
		return;

	/* change operation mode to RUN only when each engine is loading */
	if (LP8501_ENG1_IS_LOADING(mode)) {
		mode = (mode & ~LP8501_MODE_ENG1_M) | LP8501_RUN_ENG1;
		exec = (exec & ~LP8501_EXEC_ENG1_M) | LP8501_RUN_ENG1;
	}

	if (LP8501_ENG2_IS_LOADING(mode)) {
		mode = (mode & ~LP8501_MODE_ENG2_M) | LP8501_RUN_ENG2;
		exec = (exec & ~LP8501_EXEC_ENG2_M) | LP8501_RUN_ENG2;
	}

	if (LP8501_ENG3_IS_LOADING(mode)) {
		mode = (mode & ~LP8501_MODE_ENG3_M) | LP8501_RUN_ENG3;
		exec = (exec & ~LP8501_EXEC_ENG3_M) | LP8501_RUN_ENG3;
	}

	lp55xx_write(chip, LP8501_REG_OP_MODE, mode);
	lp8501_wait_opmode_done();

	lp55xx_update_bits(chip, LP8501_REG_ENABLE, LP8501_EXEC_M, exec);
}

static int lp8501_update_program_memory(struct lp55xx_chip *chip,
					const u8 *data, size_t size)
{
	u8 pattern[LP8501_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 < LP8501_PROGRAM_LENGTH; i++)
		lp55xx_write(chip, LP8501_REG_PROG_MEM + i, 0);

	i = 0;
	while ((offset < size - 1) && (i < LP8501_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, LP8501_REG_PROG_MEM + i, pattern[i]);

	return 0;

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

static void lp8501_firmware_loaded(struct lp55xx_chip *chip)
{
	const struct firmware *fw = chip->fw;

	if (fw->size > LP8501_PROGRAM_LENGTH) {
		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
			fw->size);
		return;
	}

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

	lp8501_load_engine(chip);
	lp8501_update_program_memory(chip, fw->data, fw->size);
}

static void lp8501_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, LP8501_REG_LED_PWM_BASE + led->chan_nr,
		     led->brightness);
	mutex_unlock(&chip->lock);
}

/* Chip specific configurations */
static struct lp55xx_device_config lp8501_cfg = {
	.reset = {
		.addr = LP8501_REG_RESET,
		.val  = LP8501_RESET,
	},
	.enable = {
		.addr = LP8501_REG_ENABLE,
		.val  = LP8501_ENABLE,
	},
	.max_channel  = LP8501_MAX_LEDS,
	.post_init_device   = lp8501_post_init_device,
	.brightness_work_fn = lp8501_led_brightness_work,
	.set_led_current    = lp8501_set_led_current,
	.firmware_cb        = lp8501_firmware_loaded,
	.run_engine         = lp8501_run_engine,
};

static int lp8501_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 (!dev_get_platdata(&client->dev)) {
		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 = dev_get_platdata(&client->dev);

	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 = &lp8501_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 lp8501_remove(struct i2c_client *client)
{
	struct lp55xx_led *led = i2c_get_clientdata(client);
	struct lp55xx_chip *chip = led->chip;

	lp8501_stop_engine(chip);
	lp55xx_unregister_sysfs(chip);
	lp55xx_unregister_leds(led, chip);
	lp55xx_deinit_device(chip);

	return 0;
}

static const struct i2c_device_id lp8501_id[] = {
	{ "lp8501",  0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, lp8501_id);

#ifdef CONFIG_OF
static const struct of_device_id of_lp8501_leds_match[] = {
	{ .compatible = "ti,lp8501", },
	{},
};

MODULE_DEVICE_TABLE(of, of_lp8501_leds_match);
#endif

static struct i2c_driver lp8501_driver = {
	.driver = {
		.name	= "lp8501",
		.of_match_table = of_match_ptr(of_lp8501_leds_match),
	},
	.probe		= lp8501_probe,
	.remove		= lp8501_remove,
	.id_table	= lp8501_id,
};

module_i2c_driver(lp8501_driver);

MODULE_DESCRIPTION("Texas Instruments LP8501 LED drvier");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL");