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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LP5521 LED chip driver.
  4 *
  5 * Copyright (C) 2010 Nokia Corporation
  6 * Copyright (C) 2012 Texas Instruments
  7 *
  8 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
  9 *          Milo(Woogyom) Kim <milo.kim@ti.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 10 */
 11
 12#include <linux/delay.h>
 13#include <linux/firmware.h>
 14#include <linux/i2c.h>
 15#include <linux/leds.h>
 16#include <linux/module.h>
 
 
 17#include <linux/mutex.h>
 18#include <linux/platform_data/leds-lp55xx.h>
 
 
 
 
 
 
 
 
 19#include <linux/slab.h>
 20#include <linux/of.h>
 21
 22#include "leds-lp55xx-common.h"
 
 
 
 23
 24#define LP5521_PROGRAM_LENGTH		32
 25#define LP5521_MAX_LEDS			3
 26#define LP5521_CMD_DIRECT		0x3F
 
 
 
 
 27
 28/* Registers */
 29#define LP5521_REG_ENABLE		0x00
 30#define LP5521_REG_OP_MODE		0x01
 31#define LP5521_REG_R_PWM		0x02
 32#define LP5521_REG_G_PWM		0x03
 33#define LP5521_REG_B_PWM		0x04
 34#define LP5521_REG_R_CURRENT		0x05
 35#define LP5521_REG_G_CURRENT		0x06
 36#define LP5521_REG_B_CURRENT		0x07
 37#define LP5521_REG_CONFIG		0x08
 
 
 
 38#define LP5521_REG_STATUS		0x0C
 39#define LP5521_REG_RESET		0x0D
 
 40#define LP5521_REG_R_PROG_MEM		0x10
 41#define LP5521_REG_G_PROG_MEM		0x30
 42#define LP5521_REG_B_PROG_MEM		0x50
 43
 
 
 
 44/* Base register to set LED current */
 45#define LP5521_REG_LED_CURRENT_BASE	LP5521_REG_R_CURRENT
 
 46/* Base register to set the brightness */
 47#define LP5521_REG_LED_PWM_BASE		LP5521_REG_R_PWM
 48
 49/* Bits in ENABLE register */
 50#define LP5521_MASTER_ENABLE		0x40	/* Chip master enable */
 51#define LP5521_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
 52#define LP5521_EXEC_RUN			0x2A
 53#define LP5521_ENABLE_DEFAULT	\
 54	(LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
 55#define LP5521_ENABLE_RUN_PROGRAM	\
 56	(LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
 57
 58/* CONFIG register */
 59#define LP5521_PWM_HF			0x40	/* PWM: 0 = 256Hz, 1 = 558Hz */
 60#define LP5521_PWRSAVE_EN		0x20	/* 1 = Power save mode */
 61#define LP5521_CP_MODE_OFF		0	/* Charge pump (CP) off */
 62#define LP5521_CP_MODE_BYPASS		8	/* CP forced to bypass mode */
 63#define LP5521_CP_MODE_1X5		0x10	/* CP forced to 1.5x mode */
 64#define LP5521_CP_MODE_AUTO		0x18	/* Automatic mode selection */
 65#define LP5521_R_TO_BATT		0x04	/* R out: 0 = CP, 1 = Vbat */
 66#define LP5521_CLK_INT			0x01	/* Internal clock */
 67#define LP5521_DEFAULT_CFG		\
 68	(LP5521_PWM_HF | LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO)
 69
 70/* Status */
 71#define LP5521_EXT_CLK_USED		0x08
 72
 73/* default R channel current register value */
 74#define LP5521_REG_R_CURR_DEFAULT	0xAF
 75
 76/* Reset register value */
 77#define LP5521_RESET			0xFF
 78
 79/* Program Memory Operations */
 80#define LP5521_MODE_R_M			0x30	/* Operation Mode Register */
 81#define LP5521_MODE_G_M			0x0C
 82#define LP5521_MODE_B_M			0x03
 83#define LP5521_LOAD_R			0x10
 84#define LP5521_LOAD_G			0x04
 85#define LP5521_LOAD_B			0x01
 86
 87#define LP5521_R_IS_LOADING(mode)	\
 88	((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
 89#define LP5521_G_IS_LOADING(mode)	\
 90	((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
 91#define LP5521_B_IS_LOADING(mode)	\
 92	((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
 
 
 
 93
 94#define LP5521_EXEC_R_M			0x30	/* Enable Register */
 95#define LP5521_EXEC_G_M			0x0C
 96#define LP5521_EXEC_B_M			0x03
 97#define LP5521_EXEC_M			0x3F
 98#define LP5521_RUN_R			0x20
 99#define LP5521_RUN_G			0x08
100#define LP5521_RUN_B			0x02
 
 
101
102static inline void lp5521_wait_opmode_done(void)
103{
104	/* operation mode change needs to be longer than 153 us */
105	usleep_range(200, 300);
106}
107
108static inline void lp5521_wait_enable_done(void)
109{
110	/* it takes more 488 us to update ENABLE register */
111	usleep_range(500, 600);
112}
113
114static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
115{
116	led->led_current = led_current;
117	lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
118		led_current);
119}
120
121static void lp5521_load_engine(struct lp55xx_chip *chip)
122{
123	enum lp55xx_engine_index idx = chip->engine_idx;
124	static const u8 mask[] = {
125		[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
126		[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
127		[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
128	};
129
130	static const u8 val[] = {
131		[LP55XX_ENGINE_1] = LP5521_LOAD_R,
132		[LP55XX_ENGINE_2] = LP5521_LOAD_G,
133		[LP55XX_ENGINE_3] = LP5521_LOAD_B,
134	};
135
136	lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
137
138	lp5521_wait_opmode_done();
139}
140
141static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
142{
143	lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
144	lp5521_wait_opmode_done();
145}
146
147static void lp5521_stop_engine(struct lp55xx_chip *chip)
148{
149	enum lp55xx_engine_index idx = chip->engine_idx;
150	static const u8 mask[] = {
151		[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
152		[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
153		[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
154	};
155
156	lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
 
 
157
158	lp5521_wait_opmode_done();
 
159}
160
161static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
162{
 
 
163	int ret;
164	u8 mode;
165	u8 exec;
166
167	/* stop engine */
168	if (!start) {
169		lp5521_stop_engine(chip);
170		lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
171		lp5521_wait_opmode_done();
172		return;
173	}
174
175	/*
176	 * To run the engine,
177	 * operation mode and enable register should updated at the same time
178	 */
179
180	ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
181	if (ret)
182		return;
183
184	ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
185	if (ret)
186		return;
187
188	/* change operation mode to RUN only when each engine is loading */
189	if (LP5521_R_IS_LOADING(mode)) {
190		mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
191		exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
192	}
193
194	if (LP5521_G_IS_LOADING(mode)) {
195		mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
196		exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
197	}
198
199	if (LP5521_B_IS_LOADING(mode)) {
200		mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
201		exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
202	}
203
204	lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
205	lp5521_wait_opmode_done();
 
 
 
206
207	lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
208	lp5521_wait_enable_done();
209}
210
211static int lp5521_update_program_memory(struct lp55xx_chip *chip,
212					const u8 *data, size_t size)
213{
214	enum lp55xx_engine_index idx = chip->engine_idx;
215	u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
216	static const u8 addr[] = {
217		[LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
218		[LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
219		[LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
220	};
221	unsigned cmd;
222	char c[3];
223	int nrchars;
224	int ret;
225	int offset = 0;
226	int i = 0;
227
228	while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
229		/* separate sscanfs because length is working only for %s */
230		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
231		if (ret != 1)
232			goto err;
233
234		ret = sscanf(c, "%2x", &cmd);
235		if (ret != 1)
236			goto err;
237
238		pattern[i] = (u8)cmd;
239		offset += nrchars;
240		i++;
241	}
242
243	/* Each instruction is 16bit long. Check that length is even */
244	if (i % 2)
245		goto err;
246
247	for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
248		ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
249		if (ret)
250			return -EINVAL;
251	}
252
253	return size;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
254
255err:
256	dev_err(&chip->cl->dev, "wrong pattern format\n");
257	return -EINVAL;
258}
259
260static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
261{
262	const struct firmware *fw = chip->fw;
 
 
 
263
264	if (fw->size > LP5521_PROGRAM_LENGTH) {
265		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
266			fw->size);
267		return;
 
 
 
268	}
269
270	/*
271	 * Program memory sequence
272	 *  1) set engine mode to "LOAD"
273	 *  2) write firmware data into program memory
274	 */
275
276	lp5521_load_engine(chip);
277	lp5521_update_program_memory(chip, fw->data, fw->size);
278}
279
280static int lp5521_post_init_device(struct lp55xx_chip *chip)
281{
 
282	int ret;
283	u8 val;
284
285	/*
286	 * Make sure that the chip is reset by reading back the r channel
287	 * current reg. This is dummy read is required on some platforms -
288	 * otherwise further access to the R G B channels in the
289	 * LP5521_REG_ENABLE register will not have any effect - strange!
290	 */
291	ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
292	if (ret) {
293		dev_err(&chip->cl->dev, "error in resetting chip\n");
294		return ret;
295	}
296	if (val != LP5521_REG_R_CURR_DEFAULT) {
297		dev_err(&chip->cl->dev,
298			"unexpected data in register (expected 0x%x got 0x%x)\n",
299			LP5521_REG_R_CURR_DEFAULT, val);
300		ret = -EINVAL;
301		return ret;
302	}
303	usleep_range(10000, 20000);
304
305	/* Set all PWMs to direct control mode */
306	ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
307
308	/* Update configuration for the clock setting */
309	val = LP5521_DEFAULT_CFG;
310	if (!lp55xx_is_extclk_used(chip))
311		val |= LP5521_CLK_INT;
312
313	ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
314	if (ret)
315		return ret;
316
317	/* Initialize all channels PWM to zero -> leds off */
318	lp55xx_write(chip, LP5521_REG_R_PWM, 0);
319	lp55xx_write(chip, LP5521_REG_G_PWM, 0);
320	lp55xx_write(chip, LP5521_REG_B_PWM, 0);
321
322	/* Set engines are set to run state when OP_MODE enables engines */
323	ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
324	if (ret)
325		return ret;
326
327	lp5521_wait_enable_done();
328
329	return 0;
330}
331
332static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
333{
334	struct lp55xx_platform_data *pdata = chip->pdata;
335	int ret;
336	u8 status;
337
338	ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
339	if (ret < 0)
340		return ret;
341
342	if (pdata->clock_mode != LP55XX_CLOCK_EXT)
343		return 0;
344
345	/* Check that ext clock is really in use if requested */
346	if  ((status & LP5521_EXT_CLK_USED) == 0)
347		return -EIO;
348
349	return 0;
350}
351
352static int lp5521_multicolor_brightness(struct lp55xx_led *led)
 
353{
354	struct lp55xx_chip *chip = led->chip;
355	int ret;
356	int i;
 
 
 
 
 
 
 
 
 
357
358	mutex_lock(&chip->lock);
359	for (i = 0; i < led->mc_cdev.num_colors; i++) {
360		ret = lp55xx_write(chip,
361				   LP5521_REG_LED_PWM_BASE +
362				   led->mc_cdev.subled_info[i].channel,
363				   led->mc_cdev.subled_info[i].brightness);
364		if (ret)
365			break;
366	}
367	mutex_unlock(&chip->lock);
368	return ret;
369}
370
371static int lp5521_led_brightness(struct lp55xx_led *led)
 
372{
373	struct lp55xx_chip *chip = led->chip;
374	int ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
375
376	mutex_lock(&chip->lock);
377	ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
378		led->brightness);
 
 
379	mutex_unlock(&chip->lock);
380
381	return ret;
 
 
 
 
 
 
 
 
382}
383
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
384static ssize_t show_engine_mode(struct device *dev,
385				struct device_attribute *attr,
386				char *buf, int nr)
387{
388	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
389	struct lp55xx_chip *chip = led->chip;
390	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
391
392	switch (mode) {
393	case LP55XX_ENGINE_RUN:
394		return sprintf(buf, "run\n");
395	case LP55XX_ENGINE_LOAD:
396		return sprintf(buf, "load\n");
397	case LP55XX_ENGINE_DISABLED:
 
398	default:
399		return sprintf(buf, "disabled\n");
400	}
401}
 
 
 
 
 
 
 
 
402show_mode(1)
403show_mode(2)
404show_mode(3)
405
406static ssize_t store_engine_mode(struct device *dev,
407				 struct device_attribute *attr,
408				 const char *buf, size_t len, int nr)
409{
410	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
411	struct lp55xx_chip *chip = led->chip;
412	struct lp55xx_engine *engine = &chip->engines[nr - 1];
413
414	mutex_lock(&chip->lock);
415
416	chip->engine_idx = nr;
417
418	if (!strncmp(buf, "run", 3)) {
419		lp5521_run_engine(chip, true);
420		engine->mode = LP55XX_ENGINE_RUN;
421	} else if (!strncmp(buf, "load", 4)) {
422		lp5521_stop_engine(chip);
423		lp5521_load_engine(chip);
424		engine->mode = LP55XX_ENGINE_LOAD;
425	} else if (!strncmp(buf, "disabled", 8)) {
426		lp5521_stop_engine(chip);
427		engine->mode = LP55XX_ENGINE_DISABLED;
428	}
429
430	mutex_unlock(&chip->lock);
431
432	return len;
433}
 
 
 
 
 
 
 
 
434store_mode(1)
435store_mode(2)
436store_mode(3)
437
438static ssize_t store_engine_load(struct device *dev,
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
439			     struct device_attribute *attr,
440			     const char *buf, size_t len, int nr)
441{
442	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
443	struct lp55xx_chip *chip = led->chip;
444	int ret;
 
 
445
446	mutex_lock(&chip->lock);
 
447
448	chip->engine_idx = nr;
449	lp5521_load_engine(chip);
450	ret = lp5521_update_program_memory(chip, buf, len);
451
 
 
452	mutex_unlock(&chip->lock);
453
454	return ret;
 
 
 
 
 
455}
456store_load(1)
457store_load(2)
458store_load(3)
459
460static ssize_t lp5521_selftest(struct device *dev,
461			       struct device_attribute *attr,
462			       char *buf)
463{
464	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
465	struct lp55xx_chip *chip = led->chip;
466	int ret;
467
468	mutex_lock(&chip->lock);
469	ret = lp5521_run_selftest(chip, buf);
470	mutex_unlock(&chip->lock);
471
472	return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");
473}
474
 
 
 
 
 
 
 
 
 
 
 
 
 
 
475/* device attributes */
476static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
477static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
478static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
479static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
480static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
481static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
482static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
 
 
 
483
484static struct attribute *lp5521_attributes[] = {
485	&dev_attr_engine1_mode.attr,
486	&dev_attr_engine2_mode.attr,
487	&dev_attr_engine3_mode.attr,
 
488	&dev_attr_engine1_load.attr,
489	&dev_attr_engine2_load.attr,
490	&dev_attr_engine3_load.attr,
491	&dev_attr_selftest.attr,
492	NULL
493};
494
495static const struct attribute_group lp5521_group = {
496	.attrs = lp5521_attributes,
497};
498
499/* Chip specific configurations */
500static struct lp55xx_device_config lp5521_cfg = {
501	.reset = {
502		.addr = LP5521_REG_RESET,
503		.val  = LP5521_RESET,
504	},
505	.enable = {
506		.addr = LP5521_REG_ENABLE,
507		.val  = LP5521_ENABLE_DEFAULT,
508	},
509	.max_channel  = LP5521_MAX_LEDS,
510	.post_init_device   = lp5521_post_init_device,
511	.brightness_fn      = lp5521_led_brightness,
512	.multicolor_brightness_fn = lp5521_multicolor_brightness,
513	.set_led_current    = lp5521_set_led_current,
514	.firmware_cb        = lp5521_firmware_loaded,
515	.run_engine         = lp5521_run_engine,
516	.dev_attr_group     = &lp5521_group,
517};
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
518
519static int lp5521_probe(struct i2c_client *client,
520			const struct i2c_device_id *id)
521{
522	int ret;
523	struct lp55xx_chip *chip;
524	struct lp55xx_led *led;
525	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
526	struct device_node *np = dev_of_node(&client->dev);
527
528	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
529	if (!chip)
530		return -ENOMEM;
531
532	chip->cfg = &lp5521_cfg;
 
 
 
533
534	if (!pdata) {
535		if (np) {
536			pdata = lp55xx_of_populate_pdata(&client->dev, np,
537							 chip);
538			if (IS_ERR(pdata))
539				return PTR_ERR(pdata);
540		} else {
541			dev_err(&client->dev, "no platform data\n");
542			return -EINVAL;
543		}
544	}
545
546	led = devm_kcalloc(&client->dev,
547			pdata->num_channels, sizeof(*led), GFP_KERNEL);
548	if (!led)
549		return -ENOMEM;
550
551	chip->cl = client;
552	chip->pdata = pdata;
553
554	mutex_init(&chip->lock);
555
556	i2c_set_clientdata(client, led);
557
558	ret = lp55xx_init_device(chip);
559	if (ret)
560		goto err_init;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
561
562	dev_info(&client->dev, "%s programmable led chip found\n", id->name);
563
564	ret = lp55xx_register_leds(led, chip);
565	if (ret)
566		goto err_out;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
567
568	ret = lp55xx_register_sysfs(chip);
 
 
 
 
 
 
569	if (ret) {
570		dev_err(&client->dev, "registering sysfs failed\n");
571		goto err_out;
572	}
573
574	return 0;
575
576err_out:
577	lp55xx_deinit_device(chip);
578err_init:
 
 
 
 
 
 
 
579	return ret;
580}
581
582static void lp5521_remove(struct i2c_client *client)
583{
584	struct lp55xx_led *led = i2c_get_clientdata(client);
585	struct lp55xx_chip *chip = led->chip;
 
 
 
 
 
 
 
586
587	lp5521_stop_all_engines(chip);
588	lp55xx_unregister_sysfs(chip);
589	lp55xx_deinit_device(chip);
 
 
 
590}
591
592static const struct i2c_device_id lp5521_id[] = {
593	{ "lp5521", 0 }, /* Three channel chip */
594	{ }
595};
596MODULE_DEVICE_TABLE(i2c, lp5521_id);
597
598#ifdef CONFIG_OF
599static const struct of_device_id of_lp5521_leds_match[] = {
600	{ .compatible = "national,lp5521", },
601	{},
602};
603
604MODULE_DEVICE_TABLE(of, of_lp5521_leds_match);
605#endif
606static struct i2c_driver lp5521_driver = {
607	.driver = {
608		.name	= "lp5521",
609		.of_match_table = of_match_ptr(of_lp5521_leds_match),
610	},
611	.probe		= lp5521_probe,
612	.remove		= lp5521_remove,
613	.id_table	= lp5521_id,
614};
615
616module_i2c_driver(lp5521_driver);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
617
618MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
619MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
620MODULE_DESCRIPTION("LP5521 LED engine");
621MODULE_LICENSE("GPL v2");
v3.1
 
  1/*
  2 * LP5521 LED chip driver.
  3 *
  4 * Copyright (C) 2010 Nokia Corporation
 
  5 *
  6 * Contact: Samu Onkalo <samu.p.onkalo@nokia.com>
  7 *
  8 * This program is free software; you can redistribute it and/or
  9 * modify it under the terms of the GNU General Public License
 10 * version 2 as published by the Free Software Foundation.
 11 *
 12 * This program is distributed in the hope that it will be useful, but
 13 * WITHOUT ANY WARRANTY; without even the implied warranty of
 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU
 15 * General Public License for more details.
 16 *
 17 * You should have received a copy of the GNU General Public License
 18 * along with this program; if not, write to the Free Software
 19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 20 * 02110-1301 USA
 21 */
 22
 
 
 
 
 23#include <linux/module.h>
 24#include <linux/init.h>
 25#include <linux/i2c.h>
 26#include <linux/mutex.h>
 27#include <linux/gpio.h>
 28#include <linux/interrupt.h>
 29#include <linux/delay.h>
 30#include <linux/ctype.h>
 31#include <linux/spinlock.h>
 32#include <linux/wait.h>
 33#include <linux/leds.h>
 34#include <linux/leds-lp5521.h>
 35#include <linux/workqueue.h>
 36#include <linux/slab.h>
 
 37
 38#define LP5521_PROGRAM_LENGTH		32	/* in bytes */
 39
 40#define LP5521_MAX_LEDS			3	/* Maximum number of LEDs */
 41#define LP5521_MAX_ENGINES		3	/* Maximum number of engines */
 42
 43#define LP5521_ENG_MASK_BASE		0x30	/* 00110000 */
 44#define LP5521_ENG_STATUS_MASK		0x07	/* 00000111 */
 45
 46#define LP5521_CMD_LOAD			0x15	/* 00010101 */
 47#define LP5521_CMD_RUN			0x2a	/* 00101010 */
 48#define LP5521_CMD_DIRECT		0x3f	/* 00111111 */
 49#define LP5521_CMD_DISABLED		0x00	/* 00000000 */
 50
 51/* Registers */
 52#define LP5521_REG_ENABLE		0x00
 53#define LP5521_REG_OP_MODE		0x01
 54#define LP5521_REG_R_PWM		0x02
 55#define LP5521_REG_G_PWM		0x03
 56#define LP5521_REG_B_PWM		0x04
 57#define LP5521_REG_R_CURRENT		0x05
 58#define LP5521_REG_G_CURRENT		0x06
 59#define LP5521_REG_B_CURRENT		0x07
 60#define LP5521_REG_CONFIG		0x08
 61#define LP5521_REG_R_CHANNEL_PC		0x09
 62#define LP5521_REG_G_CHANNEL_PC		0x0A
 63#define LP5521_REG_B_CHANNEL_PC		0x0B
 64#define LP5521_REG_STATUS		0x0C
 65#define LP5521_REG_RESET		0x0D
 66#define LP5521_REG_GPO			0x0E
 67#define LP5521_REG_R_PROG_MEM		0x10
 68#define LP5521_REG_G_PROG_MEM		0x30
 69#define LP5521_REG_B_PROG_MEM		0x50
 70
 71#define LP5521_PROG_MEM_BASE		LP5521_REG_R_PROG_MEM
 72#define LP5521_PROG_MEM_SIZE		0x20
 73
 74/* Base register to set LED current */
 75#define LP5521_REG_LED_CURRENT_BASE	LP5521_REG_R_CURRENT
 76
 77/* Base register to set the brightness */
 78#define LP5521_REG_LED_PWM_BASE		LP5521_REG_R_PWM
 79
 80/* Bits in ENABLE register */
 81#define LP5521_MASTER_ENABLE		0x40	/* Chip master enable */
 82#define LP5521_LOGARITHMIC_PWM		0x80	/* Logarithmic PWM adjustment */
 83#define LP5521_EXEC_RUN			0x2A
 
 
 
 
 84
 85/* Bits in CONFIG register */
 86#define LP5521_PWM_HF			0x40	/* PWM: 0 = 256Hz, 1 = 558Hz */
 87#define LP5521_PWRSAVE_EN		0x20	/* 1 = Power save mode */
 88#define LP5521_CP_MODE_OFF		0	/* Charge pump (CP) off */
 89#define LP5521_CP_MODE_BYPASS		8	/* CP forced to bypass mode */
 90#define LP5521_CP_MODE_1X5		0x10	/* CP forced to 1.5x mode */
 91#define LP5521_CP_MODE_AUTO		0x18	/* Automatic mode selection */
 92#define LP5521_R_TO_BATT		4	/* R out: 0 = CP, 1 = Vbat */
 93#define LP5521_CLK_SRC_EXT		0	/* Ext-clk source (CLK_32K) */
 94#define LP5521_CLK_INT			1	/* Internal clock */
 95#define LP5521_CLK_AUTO			2	/* Automatic clock selection */
 96
 97/* Status */
 98#define LP5521_EXT_CLK_USED		0x08
 99
100struct lp5521_engine {
101	int		id;
102	u8		mode;
103	u8		prog_page;
104	u8		engine_mask;
105};
 
 
 
 
 
 
 
106
107struct lp5521_led {
108	int			id;
109	u8			chan_nr;
110	u8			led_current;
111	u8			max_current;
112	struct led_classdev	cdev;
113	struct work_struct	brightness_work;
114	u8			brightness;
115};
116
117struct lp5521_chip {
118	struct lp5521_platform_data *pdata;
119	struct mutex		lock; /* Serialize control */
120	struct i2c_client	*client;
121	struct lp5521_engine	engines[LP5521_MAX_ENGINES];
122	struct lp5521_led	leds[LP5521_MAX_LEDS];
123	u8			num_channels;
124	u8			num_leds;
125};
126
127static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
128{
129	return container_of(cdev, struct lp5521_led, cdev);
 
130}
131
132static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
133{
134	return container_of(engine, struct lp5521_chip,
135			    engines[engine->id - 1]);
136}
137
138static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
139{
140	return container_of(led, struct lp5521_chip,
141			    leds[led->id]);
 
142}
143
144static void lp5521_led_brightness_work(struct work_struct *work);
 
 
 
 
 
 
 
 
 
 
 
 
 
145
146static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
 
 
 
 
 
147{
148	return i2c_smbus_write_byte_data(client, reg, value);
 
149}
150
151static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
152{
153	s32 ret;
 
 
 
 
 
154
155	ret = i2c_smbus_read_byte_data(client, reg);
156	if (ret < 0)
157		return -EIO;
158
159	*buf = ret;
160	return 0;
161}
162
163static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
164{
165	struct lp5521_chip *chip = engine_to_lp5521(engine);
166	struct i2c_client *client = chip->client;
167	int ret;
168	u8 engine_state;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
169
170	/* Only transition between RUN and DIRECT mode are handled here */
171	if (mode == LP5521_CMD_LOAD)
172		return 0;
 
 
 
 
 
 
 
 
 
 
173
174	if (mode == LP5521_CMD_DISABLED)
175		mode = LP5521_CMD_DIRECT;
 
 
176
177	ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
 
 
 
178
179	/* set mode only for this engine */
180	engine_state &= ~(engine->engine_mask);
181	mode &= engine->engine_mask;
182	engine_state |= mode;
183	ret |= lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
184
185	return ret;
 
186}
187
188static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
 
189{
190	struct lp5521_chip *chip = engine_to_lp5521(eng);
191	struct i2c_client *client = chip->client;
 
 
 
 
 
 
 
 
192	int ret;
193	int addr;
194	u8 mode;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
195
196	/* move current engine to direct mode and remember the state */
197	ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
198	/* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
199	usleep_range(1000, 2000);
200	ret |= lp5521_read(client, LP5521_REG_OP_MODE, &mode);
201
202	/* For loading, all the engines to load mode */
203	lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
204	/* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
205	usleep_range(1000, 2000);
206	lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
207	/* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
208	usleep_range(1000, 2000);
209
210	addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
211	i2c_smbus_write_i2c_block_data(client,
212				addr,
213				LP5521_PROG_MEM_SIZE,
214				pattern);
215
216	ret |= lp5521_write(client, LP5521_REG_OP_MODE, mode);
217	return ret;
 
218}
219
220static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
221{
222	return lp5521_write(chip->client,
223		    LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
224		    curr);
225}
226
227static void lp5521_init_engine(struct lp5521_chip *chip)
228{
229	int i;
230	for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
231		chip->engines[i].id = i + 1;
232		chip->engines[i].engine_mask = LP5521_ENG_MASK_BASE >> (i * 2);
233		chip->engines[i].prog_page = i;
234	}
 
 
 
 
 
 
 
 
 
235}
236
237static int lp5521_configure(struct i2c_client *client)
238{
239	struct lp5521_chip *chip = i2c_get_clientdata(client);
240	int ret;
 
241
242	lp5521_init_engine(chip);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
243
244	/* Set all PWMs to direct control mode */
245	ret = lp5521_write(client, LP5521_REG_OP_MODE, 0x3F);
 
 
 
 
 
246
247	/* Enable auto-powersave, set charge pump to auto, red to battery */
248	ret |= lp5521_write(client, LP5521_REG_CONFIG,
249		LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
250
251	/* Initialize all channels PWM to zero -> leds off */
252	ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
253	ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
254	ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
255
256	/* Set engines are set to run state when OP_MODE enables engines */
257	ret |= lp5521_write(client, LP5521_REG_ENABLE,
258			LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM |
259			LP5521_EXEC_RUN);
260	/* enable takes 500us. 1 - 2 ms leaves some margin */
261	usleep_range(1000, 2000);
262
263	return ret;
264}
265
266static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
267{
 
268	int ret;
269	u8 status;
270
271	ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
272	if (ret < 0)
273		return ret;
274
 
 
 
275	/* Check that ext clock is really in use if requested */
276	if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
277		if  ((status & LP5521_EXT_CLK_USED) == 0)
278			return -EIO;
279	return 0;
280}
281
282static void lp5521_set_brightness(struct led_classdev *cdev,
283			     enum led_brightness brightness)
284{
285	struct lp5521_led *led = cdev_to_led(cdev);
286	led->brightness = (u8)brightness;
287	schedule_work(&led->brightness_work);
288}
289
290static void lp5521_led_brightness_work(struct work_struct *work)
291{
292	struct lp5521_led *led = container_of(work,
293					      struct lp5521_led,
294					      brightness_work);
295	struct lp5521_chip *chip = led_to_lp5521(led);
296	struct i2c_client *client = chip->client;
297
298	mutex_lock(&chip->lock);
299	lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
300		led->brightness);
 
 
 
 
 
 
301	mutex_unlock(&chip->lock);
 
302}
303
304/* Detect the chip by setting its ENABLE register and reading it back. */
305static int lp5521_detect(struct i2c_client *client)
306{
 
307	int ret;
308	u8 buf;
309
310	ret = lp5521_write(client, LP5521_REG_ENABLE,
311			LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM);
312	if (ret)
313		return ret;
314	/* enable takes 500us. 1 - 2 ms leaves some margin */
315	usleep_range(1000, 2000);
316	ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
317	if (ret)
318		return ret;
319	if (buf != (LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM))
320		return -ENODEV;
321
322	return 0;
323}
324
325/* Set engine mode and create appropriate sysfs attributes, if required. */
326static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
327{
328	int ret = 0;
329
330	/* if in that mode already do nothing, except for run */
331	if (mode == engine->mode && mode != LP5521_CMD_RUN)
332		return 0;
333
334	if (mode == LP5521_CMD_RUN) {
335		ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
336	} else if (mode == LP5521_CMD_LOAD) {
337		lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
338		lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
339	} else if (mode == LP5521_CMD_DISABLED) {
340		lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
341	}
342
343	engine->mode = mode;
344
345	return ret;
346}
347
348static int lp5521_do_store_load(struct lp5521_engine *engine,
349				const char *buf, size_t len)
350{
351	struct lp5521_chip *chip = engine_to_lp5521(engine);
352	struct i2c_client *client = chip->client;
353	int  ret, nrchars, offset = 0, i = 0;
354	char c[3];
355	unsigned cmd;
356	u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
357
358	while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
359		/* separate sscanfs because length is working only for %s */
360		ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
361		if (ret != 2)
362			goto fail;
363		ret = sscanf(c, "%2x", &cmd);
364		if (ret != 1)
365			goto fail;
366		pattern[i] = (u8)cmd;
367
368		offset += nrchars;
369		i++;
370	}
371
372	/* Each instruction is 16bit long. Check that length is even */
373	if (i % 2)
374		goto fail;
375
376	mutex_lock(&chip->lock);
377	if (engine->mode == LP5521_CMD_LOAD)
378		ret = lp5521_load_program(engine, pattern);
379	else
380		ret = -EINVAL;
381	mutex_unlock(&chip->lock);
382
383	if (ret) {
384		dev_err(&client->dev, "failed loading pattern\n");
385		return ret;
386	}
387
388	return len;
389fail:
390	dev_err(&client->dev, "wrong pattern format\n");
391	return -EINVAL;
392}
393
394static ssize_t store_engine_load(struct device *dev,
395				     struct device_attribute *attr,
396				     const char *buf, size_t len, int nr)
397{
398	struct i2c_client *client = to_i2c_client(dev);
399	struct lp5521_chip *chip = i2c_get_clientdata(client);
400	return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
401}
402
403#define store_load(nr)							\
404static ssize_t store_engine##nr##_load(struct device *dev,		\
405				     struct device_attribute *attr,	\
406				     const char *buf, size_t len)	\
407{									\
408	return store_engine_load(dev, attr, buf, len, nr);		\
409}
410store_load(1)
411store_load(2)
412store_load(3)
413
414static ssize_t show_engine_mode(struct device *dev,
415				struct device_attribute *attr,
416				char *buf, int nr)
417{
418	struct i2c_client *client = to_i2c_client(dev);
419	struct lp5521_chip *chip = i2c_get_clientdata(client);
420	switch (chip->engines[nr - 1].mode) {
421	case LP5521_CMD_RUN:
 
 
422		return sprintf(buf, "run\n");
423	case LP5521_CMD_LOAD:
424		return sprintf(buf, "load\n");
425	case LP5521_CMD_DISABLED:
426		return sprintf(buf, "disabled\n");
427	default:
428		return sprintf(buf, "disabled\n");
429	}
430}
431
432#define show_mode(nr)							\
433static ssize_t show_engine##nr##_mode(struct device *dev,		\
434				    struct device_attribute *attr,	\
435				    char *buf)				\
436{									\
437	return show_engine_mode(dev, attr, buf, nr);			\
438}
439show_mode(1)
440show_mode(2)
441show_mode(3)
442
443static ssize_t store_engine_mode(struct device *dev,
444				 struct device_attribute *attr,
445				 const char *buf, size_t len, int nr)
446{
447	struct i2c_client *client = to_i2c_client(dev);
448	struct lp5521_chip *chip = i2c_get_clientdata(client);
449	struct lp5521_engine *engine = &chip->engines[nr - 1];
 
450	mutex_lock(&chip->lock);
451
452	if (!strncmp(buf, "run", 3))
453		lp5521_set_mode(engine, LP5521_CMD_RUN);
454	else if (!strncmp(buf, "load", 4))
455		lp5521_set_mode(engine, LP5521_CMD_LOAD);
456	else if (!strncmp(buf, "disabled", 8))
457		lp5521_set_mode(engine, LP5521_CMD_DISABLED);
 
 
 
 
 
 
 
458
459	mutex_unlock(&chip->lock);
 
460	return len;
461}
462
463#define store_mode(nr)							\
464static ssize_t store_engine##nr##_mode(struct device *dev,		\
465				     struct device_attribute *attr,	\
466				     const char *buf, size_t len)	\
467{									\
468	return store_engine_mode(dev, attr, buf, len, nr);		\
469}
470store_mode(1)
471store_mode(2)
472store_mode(3)
473
474static ssize_t show_max_current(struct device *dev,
475			    struct device_attribute *attr,
476			    char *buf)
477{
478	struct led_classdev *led_cdev = dev_get_drvdata(dev);
479	struct lp5521_led *led = cdev_to_led(led_cdev);
480
481	return sprintf(buf, "%d\n", led->max_current);
482}
483
484static ssize_t show_current(struct device *dev,
485			    struct device_attribute *attr,
486			    char *buf)
487{
488	struct led_classdev *led_cdev = dev_get_drvdata(dev);
489	struct lp5521_led *led = cdev_to_led(led_cdev);
490
491	return sprintf(buf, "%d\n", led->led_current);
492}
493
494static ssize_t store_current(struct device *dev,
495			     struct device_attribute *attr,
496			     const char *buf, size_t len)
497{
498	struct led_classdev *led_cdev = dev_get_drvdata(dev);
499	struct lp5521_led *led = cdev_to_led(led_cdev);
500	struct lp5521_chip *chip = led_to_lp5521(led);
501	ssize_t ret;
502	unsigned long curr;
503
504	if (strict_strtoul(buf, 0, &curr))
505		return -EINVAL;
506
507	if (curr > led->max_current)
508		return -EINVAL;
 
509
510	mutex_lock(&chip->lock);
511	ret = lp5521_set_led_current(chip, led->id, curr);
512	mutex_unlock(&chip->lock);
513
514	if (ret < 0)
515		return ret;
516
517	led->led_current = (u8)curr;
518
519	return len;
520}
 
 
 
521
522static ssize_t lp5521_selftest(struct device *dev,
523			       struct device_attribute *attr,
524			       char *buf)
525{
526	struct i2c_client *client = to_i2c_client(dev);
527	struct lp5521_chip *chip = i2c_get_clientdata(client);
528	int ret;
529
530	mutex_lock(&chip->lock);
531	ret = lp5521_run_selftest(chip, buf);
532	mutex_unlock(&chip->lock);
533	return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
 
534}
535
536/* led class device attributes */
537static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, show_current, store_current);
538static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
539
540static struct attribute *lp5521_led_attributes[] = {
541	&dev_attr_led_current.attr,
542	&dev_attr_max_current.attr,
543	NULL,
544};
545
546static struct attribute_group lp5521_led_attribute_group = {
547	.attrs = lp5521_led_attributes
548};
549
550/* device attributes */
551static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
552		   show_engine1_mode, store_engine1_mode);
553static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
554		   show_engine2_mode, store_engine2_mode);
555static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
556		   show_engine3_mode, store_engine3_mode);
557static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
558static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
559static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
560static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
561
562static struct attribute *lp5521_attributes[] = {
563	&dev_attr_engine1_mode.attr,
564	&dev_attr_engine2_mode.attr,
565	&dev_attr_engine3_mode.attr,
566	&dev_attr_selftest.attr,
567	&dev_attr_engine1_load.attr,
568	&dev_attr_engine2_load.attr,
569	&dev_attr_engine3_load.attr,
 
570	NULL
571};
572
573static const struct attribute_group lp5521_group = {
574	.attrs = lp5521_attributes,
575};
576
577static int lp5521_register_sysfs(struct i2c_client *client)
578{
579	struct device *dev = &client->dev;
580	return sysfs_create_group(&dev->kobj, &lp5521_group);
581}
582
583static void lp5521_unregister_sysfs(struct i2c_client *client)
584{
585	struct lp5521_chip *chip = i2c_get_clientdata(client);
586	struct device *dev = &client->dev;
587	int i;
588
589	sysfs_remove_group(&dev->kobj, &lp5521_group);
590
591	for (i = 0; i < chip->num_leds; i++)
592		sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
593				&lp5521_led_attribute_group);
594}
595
596static int __devinit lp5521_init_led(struct lp5521_led *led,
597				struct i2c_client *client,
598				int chan, struct lp5521_platform_data *pdata)
599{
600	struct device *dev = &client->dev;
601	char name[32];
602	int res;
603
604	if (chan >= LP5521_MAX_LEDS)
605		return -EINVAL;
606
607	if (pdata->led_config[chan].led_current == 0)
608		return 0;
609
610	led->led_current = pdata->led_config[chan].led_current;
611	led->max_current = pdata->led_config[chan].max_current;
612	led->chan_nr = pdata->led_config[chan].chan_nr;
613
614	if (led->chan_nr >= LP5521_MAX_LEDS) {
615		dev_err(dev, "Use channel numbers between 0 and %d\n",
616			LP5521_MAX_LEDS - 1);
617		return -EINVAL;
618	}
619
620	snprintf(name, sizeof(name), "%s:channel%d",
621			pdata->label ?: client->name, chan);
622	led->cdev.brightness_set = lp5521_set_brightness;
623	led->cdev.name = name;
624	res = led_classdev_register(dev, &led->cdev);
625	if (res < 0) {
626		dev_err(dev, "couldn't register led on channel %d\n", chan);
627		return res;
628	}
629
630	res = sysfs_create_group(&led->cdev.dev->kobj,
631			&lp5521_led_attribute_group);
632	if (res < 0) {
633		dev_err(dev, "couldn't register current attribute\n");
634		led_classdev_unregister(&led->cdev);
635		return res;
636	}
637	return 0;
638}
639
640static int __devinit lp5521_probe(struct i2c_client *client,
641			const struct i2c_device_id *id)
642{
643	struct lp5521_chip		*chip;
644	struct lp5521_platform_data	*pdata;
645	int ret, i, led;
 
 
646
647	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
648	if (!chip)
649		return -ENOMEM;
650
651	i2c_set_clientdata(client, chip);
652	chip->client = client;
653
654	pdata = client->dev.platform_data;
655
656	if (!pdata) {
657		dev_err(&client->dev, "no platform data\n");
658		ret = -EINVAL;
659		goto fail1;
 
 
 
 
 
 
660	}
661
 
 
 
 
 
 
 
 
662	mutex_init(&chip->lock);
663
664	chip->pdata   = pdata;
665
666	if (pdata->setup_resources) {
667		ret = pdata->setup_resources();
668		if (ret < 0)
669			goto fail1;
670	}
671
672	if (pdata->enable) {
673		pdata->enable(0);
674		usleep_range(1000, 2000); /* Keep enable down at least 1ms */
675		pdata->enable(1);
676		usleep_range(1000, 2000); /* 500us abs min. */
677	}
678
679	lp5521_write(client, LP5521_REG_RESET, 0xff);
680	usleep_range(10000, 20000); /*
681				     * Exact value is not available. 10 - 20ms
682				     * appears to be enough for reset.
683				     */
684	ret = lp5521_detect(client);
685
686	if (ret) {
687		dev_err(&client->dev, "Chip not found\n");
688		goto fail2;
689	}
690
691	dev_info(&client->dev, "%s programmable led chip found\n", id->name);
692
693	ret = lp5521_configure(client);
694	if (ret < 0) {
695		dev_err(&client->dev, "error configuring chip\n");
696		goto fail2;
697	}
698
699	/* Initialize leds */
700	chip->num_channels = pdata->num_channels;
701	chip->num_leds = 0;
702	led = 0;
703	for (i = 0; i < pdata->num_channels; i++) {
704		/* Do not initialize channels that are not connected */
705		if (pdata->led_config[i].led_current == 0)
706			continue;
707
708		ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
709		if (ret) {
710			dev_err(&client->dev, "error initializing leds\n");
711			goto fail3;
712		}
713		chip->num_leds++;
714
715		chip->leds[led].id = led;
716		/* Set initial LED current */
717		lp5521_set_led_current(chip, led,
718				chip->leds[led].led_current);
719
720		INIT_WORK(&(chip->leds[led].brightness_work),
721			lp5521_led_brightness_work);
722
723		led++;
724	}
725
726	ret = lp5521_register_sysfs(client);
727	if (ret) {
728		dev_err(&client->dev, "registering sysfs failed\n");
729		goto fail3;
730	}
731	return ret;
732fail3:
733	for (i = 0; i < chip->num_leds; i++) {
734		led_classdev_unregister(&chip->leds[i].cdev);
735		cancel_work_sync(&chip->leds[i].brightness_work);
736	}
737fail2:
738	if (pdata->enable)
739		pdata->enable(0);
740	if (pdata->release_resources)
741		pdata->release_resources();
742fail1:
743	kfree(chip);
744	return ret;
745}
746
747static int __devexit lp5521_remove(struct i2c_client *client)
748{
749	struct lp5521_chip *chip = i2c_get_clientdata(client);
750	int i;
751
752	lp5521_unregister_sysfs(client);
753
754	for (i = 0; i < chip->num_leds; i++) {
755		led_classdev_unregister(&chip->leds[i].cdev);
756		cancel_work_sync(&chip->leds[i].brightness_work);
757	}
758
759	if (chip->pdata->enable)
760		chip->pdata->enable(0);
761	if (chip->pdata->release_resources)
762		chip->pdata->release_resources();
763	kfree(chip);
764	return 0;
765}
766
767static const struct i2c_device_id lp5521_id[] = {
768	{ "lp5521", 0 }, /* Three channel chip */
769	{ }
770};
771MODULE_DEVICE_TABLE(i2c, lp5521_id);
772
 
 
 
 
 
 
 
 
773static struct i2c_driver lp5521_driver = {
774	.driver = {
775		.name	= "lp5521",
 
776	},
777	.probe		= lp5521_probe,
778	.remove		= __devexit_p(lp5521_remove),
779	.id_table	= lp5521_id,
780};
781
782static int __init lp5521_init(void)
783{
784	int ret;
785
786	ret = i2c_add_driver(&lp5521_driver);
787
788	if (ret < 0)
789		printk(KERN_ALERT "Adding lp5521 driver failed\n");
790
791	return ret;
792}
793
794static void __exit lp5521_exit(void)
795{
796	i2c_del_driver(&lp5521_driver);
797}
798
799module_init(lp5521_init);
800module_exit(lp5521_exit);
801
802MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
 
803MODULE_DESCRIPTION("LP5521 LED engine");
804MODULE_LICENSE("GPL v2");