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  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_MASK		0x18	/* Charge pump mode */
 62#define LP5521_CP_MODE_SHIFT		3
 63#define LP5521_R_TO_BATT		0x04	/* R out: 0 = CP, 1 = Vbat */
 64#define LP5521_CLK_INT			0x01	/* Internal clock */
 65#define LP5521_DEFAULT_CFG		(LP5521_PWM_HF | LP5521_PWRSAVE_EN)
 66
 67/* Status */
 68#define LP5521_EXT_CLK_USED		0x08
 69
 70/* default R channel current register value */
 71#define LP5521_REG_R_CURR_DEFAULT	0xAF
 72
 73/* Reset register value */
 74#define LP5521_RESET			0xFF
 75
 76/* Program Memory Operations */
 77#define LP5521_MODE_R_M			0x30	/* Operation Mode Register */
 78#define LP5521_MODE_G_M			0x0C
 79#define LP5521_MODE_B_M			0x03
 80#define LP5521_LOAD_R			0x10
 81#define LP5521_LOAD_G			0x04
 82#define LP5521_LOAD_B			0x01
 83
 84#define LP5521_R_IS_LOADING(mode)	\
 85	((mode & LP5521_MODE_R_M) == LP5521_LOAD_R)
 86#define LP5521_G_IS_LOADING(mode)	\
 87	((mode & LP5521_MODE_G_M) == LP5521_LOAD_G)
 88#define LP5521_B_IS_LOADING(mode)	\
 89	((mode & LP5521_MODE_B_M) == LP5521_LOAD_B)
 90
 91#define LP5521_EXEC_R_M			0x30	/* Enable Register */
 92#define LP5521_EXEC_G_M			0x0C
 93#define LP5521_EXEC_B_M			0x03
 94#define LP5521_EXEC_M			0x3F
 95#define LP5521_RUN_R			0x20
 96#define LP5521_RUN_G			0x08
 97#define LP5521_RUN_B			0x02
 98
 99static inline void lp5521_wait_opmode_done(void)
100{
101	/* operation mode change needs to be longer than 153 us */
102	usleep_range(200, 300);
103}
104
105static inline void lp5521_wait_enable_done(void)
106{
107	/* it takes more 488 us to update ENABLE register */
108	usleep_range(500, 600);
109}
110
111static void lp5521_set_led_current(struct lp55xx_led *led, u8 led_current)
112{
113	led->led_current = led_current;
114	lp55xx_write(led->chip, LP5521_REG_LED_CURRENT_BASE + led->chan_nr,
115		led_current);
116}
117
118static void lp5521_load_engine(struct lp55xx_chip *chip)
119{
120	enum lp55xx_engine_index idx = chip->engine_idx;
121	static const u8 mask[] = {
122		[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
123		[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
124		[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
125	};
126
127	static const u8 val[] = {
128		[LP55XX_ENGINE_1] = LP5521_LOAD_R,
129		[LP55XX_ENGINE_2] = LP5521_LOAD_G,
130		[LP55XX_ENGINE_3] = LP5521_LOAD_B,
131	};
132
133	lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], val[idx]);
134
135	lp5521_wait_opmode_done();
136}
137
138static void lp5521_stop_all_engines(struct lp55xx_chip *chip)
139{
140	lp55xx_write(chip, LP5521_REG_OP_MODE, 0);
141	lp5521_wait_opmode_done();
142}
143
144static void lp5521_stop_engine(struct lp55xx_chip *chip)
145{
146	enum lp55xx_engine_index idx = chip->engine_idx;
147	static const u8 mask[] = {
148		[LP55XX_ENGINE_1] = LP5521_MODE_R_M,
149		[LP55XX_ENGINE_2] = LP5521_MODE_G_M,
150		[LP55XX_ENGINE_3] = LP5521_MODE_B_M,
151	};
152
153	lp55xx_update_bits(chip, LP5521_REG_OP_MODE, mask[idx], 0);
154
155	lp5521_wait_opmode_done();
156}
157
158static void lp5521_run_engine(struct lp55xx_chip *chip, bool start)
159{
160	int ret;
161	u8 mode;
162	u8 exec;
163
164	/* stop engine */
165	if (!start) {
166		lp5521_stop_engine(chip);
167		lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
168		lp5521_wait_opmode_done();
169		return;
170	}
171
172	/*
173	 * To run the engine,
174	 * operation mode and enable register should updated at the same time
175	 */
176
177	ret = lp55xx_read(chip, LP5521_REG_OP_MODE, &mode);
178	if (ret)
179		return;
180
181	ret = lp55xx_read(chip, LP5521_REG_ENABLE, &exec);
182	if (ret)
183		return;
184
185	/* change operation mode to RUN only when each engine is loading */
186	if (LP5521_R_IS_LOADING(mode)) {
187		mode = (mode & ~LP5521_MODE_R_M) | LP5521_RUN_R;
188		exec = (exec & ~LP5521_EXEC_R_M) | LP5521_RUN_R;
189	}
190
191	if (LP5521_G_IS_LOADING(mode)) {
192		mode = (mode & ~LP5521_MODE_G_M) | LP5521_RUN_G;
193		exec = (exec & ~LP5521_EXEC_G_M) | LP5521_RUN_G;
194	}
195
196	if (LP5521_B_IS_LOADING(mode)) {
197		mode = (mode & ~LP5521_MODE_B_M) | LP5521_RUN_B;
198		exec = (exec & ~LP5521_EXEC_B_M) | LP5521_RUN_B;
199	}
200
201	lp55xx_write(chip, LP5521_REG_OP_MODE, mode);
202	lp5521_wait_opmode_done();
203
204	lp55xx_update_bits(chip, LP5521_REG_ENABLE, LP5521_EXEC_M, exec);
205	lp5521_wait_enable_done();
206}
207
208static int lp5521_update_program_memory(struct lp55xx_chip *chip,
209					const u8 *data, size_t size)
210{
211	enum lp55xx_engine_index idx = chip->engine_idx;
212	u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
213	static const u8 addr[] = {
214		[LP55XX_ENGINE_1] = LP5521_REG_R_PROG_MEM,
215		[LP55XX_ENGINE_2] = LP5521_REG_G_PROG_MEM,
216		[LP55XX_ENGINE_3] = LP5521_REG_B_PROG_MEM,
217	};
218	unsigned cmd;
219	char c[3];
220	int nrchars;
221	int ret;
222	int offset = 0;
223	int i = 0;
224
225	while ((offset < size - 1) && (i < LP5521_PROGRAM_LENGTH)) {
226		/* separate sscanfs because length is working only for %s */
227		ret = sscanf(data + offset, "%2s%n ", c, &nrchars);
228		if (ret != 1)
229			goto err;
230
231		ret = sscanf(c, "%2x", &cmd);
232		if (ret != 1)
233			goto err;
234
235		pattern[i] = (u8)cmd;
236		offset += nrchars;
237		i++;
238	}
239
240	/* Each instruction is 16bit long. Check that length is even */
241	if (i % 2)
242		goto err;
243
244	for (i = 0; i < LP5521_PROGRAM_LENGTH; i++) {
245		ret = lp55xx_write(chip, addr[idx] + i, pattern[i]);
246		if (ret)
247			return -EINVAL;
248	}
249
250	return size;
251
252err:
253	dev_err(&chip->cl->dev, "wrong pattern format\n");
254	return -EINVAL;
255}
256
257static void lp5521_firmware_loaded(struct lp55xx_chip *chip)
258{
259	const struct firmware *fw = chip->fw;
260
261	if (fw->size > LP5521_PROGRAM_LENGTH) {
262		dev_err(&chip->cl->dev, "firmware data size overflow: %zu\n",
263			fw->size);
264		return;
265	}
266
267	/*
268	 * Program memory sequence
269	 *  1) set engine mode to "LOAD"
270	 *  2) write firmware data into program memory
271	 */
272
273	lp5521_load_engine(chip);
274	lp5521_update_program_memory(chip, fw->data, fw->size);
275}
276
277static int lp5521_post_init_device(struct lp55xx_chip *chip)
278{
279	int ret;
280	u8 val;
281
282	/*
283	 * Make sure that the chip is reset by reading back the r channel
284	 * current reg. This is dummy read is required on some platforms -
285	 * otherwise further access to the R G B channels in the
286	 * LP5521_REG_ENABLE register will not have any effect - strange!
287	 */
288	ret = lp55xx_read(chip, LP5521_REG_R_CURRENT, &val);
289	if (ret) {
290		dev_err(&chip->cl->dev, "error in resetting chip\n");
291		return ret;
292	}
293	if (val != LP5521_REG_R_CURR_DEFAULT) {
294		dev_err(&chip->cl->dev,
295			"unexpected data in register (expected 0x%x got 0x%x)\n",
296			LP5521_REG_R_CURR_DEFAULT, val);
297		ret = -EINVAL;
298		return ret;
299	}
300	usleep_range(10000, 20000);
301
302	/* Set all PWMs to direct control mode */
303	ret = lp55xx_write(chip, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
304	if (ret)
305		return ret;
306
307	/* Update configuration for the clock setting */
308	val = LP5521_DEFAULT_CFG;
309	if (!lp55xx_is_extclk_used(chip))
310		val |= LP5521_CLK_INT;
311
312	val |= (chip->pdata->charge_pump_mode << LP5521_CP_MODE_SHIFT) & LP5521_CP_MODE_MASK;
313
314	ret = lp55xx_write(chip, LP5521_REG_CONFIG, val);
315	if (ret)
316		return ret;
317
318	/* Initialize all channels PWM to zero -> leds off */
319	lp55xx_write(chip, LP5521_REG_R_PWM, 0);
320	lp55xx_write(chip, LP5521_REG_G_PWM, 0);
321	lp55xx_write(chip, LP5521_REG_B_PWM, 0);
322
323	/* Set engines are set to run state when OP_MODE enables engines */
324	ret = lp55xx_write(chip, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
325	if (ret)
326		return ret;
327
328	lp5521_wait_enable_done();
329
330	return 0;
331}
332
333static int lp5521_run_selftest(struct lp55xx_chip *chip, char *buf)
334{
335	struct lp55xx_platform_data *pdata = chip->pdata;
336	int ret;
337	u8 status;
338
339	ret = lp55xx_read(chip, LP5521_REG_STATUS, &status);
340	if (ret < 0)
341		return ret;
342
343	if (pdata->clock_mode != LP55XX_CLOCK_EXT)
344		return 0;
345
346	/* Check that ext clock is really in use if requested */
347	if  ((status & LP5521_EXT_CLK_USED) == 0)
348		return -EIO;
349
350	return 0;
351}
352
353static int lp5521_multicolor_brightness(struct lp55xx_led *led)
354{
355	struct lp55xx_chip *chip = led->chip;
356	int ret;
357	int i;
358
359	mutex_lock(&chip->lock);
360	for (i = 0; i < led->mc_cdev.num_colors; i++) {
361		ret = lp55xx_write(chip,
362				   LP5521_REG_LED_PWM_BASE +
363				   led->mc_cdev.subled_info[i].channel,
364				   led->mc_cdev.subled_info[i].brightness);
365		if (ret)
366			break;
367	}
368	mutex_unlock(&chip->lock);
369	return ret;
370}
371
372static int lp5521_led_brightness(struct lp55xx_led *led)
373{
374	struct lp55xx_chip *chip = led->chip;
375	int ret;
376
377	mutex_lock(&chip->lock);
378	ret = lp55xx_write(chip, LP5521_REG_LED_PWM_BASE + led->chan_nr,
379		led->brightness);
380	mutex_unlock(&chip->lock);
381
382	return ret;
383}
384
385static ssize_t show_engine_mode(struct device *dev,
386				struct device_attribute *attr,
387				char *buf, int nr)
388{
389	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
390	struct lp55xx_chip *chip = led->chip;
391	enum lp55xx_engine_mode mode = chip->engines[nr - 1].mode;
392
393	switch (mode) {
394	case LP55XX_ENGINE_RUN:
395		return sprintf(buf, "run\n");
396	case LP55XX_ENGINE_LOAD:
397		return sprintf(buf, "load\n");
398	case LP55XX_ENGINE_DISABLED:
399	default:
400		return sprintf(buf, "disabled\n");
401	}
402}
403show_mode(1)
404show_mode(2)
405show_mode(3)
406
407static ssize_t store_engine_mode(struct device *dev,
408				 struct device_attribute *attr,
409				 const char *buf, size_t len, int nr)
410{
411	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
412	struct lp55xx_chip *chip = led->chip;
413	struct lp55xx_engine *engine = &chip->engines[nr - 1];
414
415	mutex_lock(&chip->lock);
416
417	chip->engine_idx = nr;
418
419	if (!strncmp(buf, "run", 3)) {
420		lp5521_run_engine(chip, true);
421		engine->mode = LP55XX_ENGINE_RUN;
422	} else if (!strncmp(buf, "load", 4)) {
423		lp5521_stop_engine(chip);
424		lp5521_load_engine(chip);
425		engine->mode = LP55XX_ENGINE_LOAD;
426	} else if (!strncmp(buf, "disabled", 8)) {
427		lp5521_stop_engine(chip);
428		engine->mode = LP55XX_ENGINE_DISABLED;
429	}
430
431	mutex_unlock(&chip->lock);
432
433	return len;
434}
435store_mode(1)
436store_mode(2)
437store_mode(3)
438
439static ssize_t store_engine_load(struct device *dev,
440			     struct device_attribute *attr,
441			     const char *buf, size_t len, int nr)
442{
443	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
444	struct lp55xx_chip *chip = led->chip;
445	int ret;
446
447	mutex_lock(&chip->lock);
448
449	chip->engine_idx = nr;
450	lp5521_load_engine(chip);
451	ret = lp5521_update_program_memory(chip, buf, len);
452
453	mutex_unlock(&chip->lock);
454
455	return ret;
456}
457store_load(1)
458store_load(2)
459store_load(3)
460
461static ssize_t lp5521_selftest(struct device *dev,
462			       struct device_attribute *attr,
463			       char *buf)
464{
465	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
466	struct lp55xx_chip *chip = led->chip;
467	int ret;
468
469	mutex_lock(&chip->lock);
470	ret = lp5521_run_selftest(chip, buf);
471	mutex_unlock(&chip->lock);
472
473	return sysfs_emit(buf, "%s\n", ret ? "FAIL" : "OK");
474}
475
476/* device attributes */
477static LP55XX_DEV_ATTR_RW(engine1_mode, show_engine1_mode, store_engine1_mode);
478static LP55XX_DEV_ATTR_RW(engine2_mode, show_engine2_mode, store_engine2_mode);
479static LP55XX_DEV_ATTR_RW(engine3_mode, show_engine3_mode, store_engine3_mode);
480static LP55XX_DEV_ATTR_WO(engine1_load, store_engine1_load);
481static LP55XX_DEV_ATTR_WO(engine2_load, store_engine2_load);
482static LP55XX_DEV_ATTR_WO(engine3_load, store_engine3_load);
483static LP55XX_DEV_ATTR_RO(selftest, lp5521_selftest);
484
485static struct attribute *lp5521_attributes[] = {
486	&dev_attr_engine1_mode.attr,
487	&dev_attr_engine2_mode.attr,
488	&dev_attr_engine3_mode.attr,
489	&dev_attr_engine1_load.attr,
490	&dev_attr_engine2_load.attr,
491	&dev_attr_engine3_load.attr,
492	&dev_attr_selftest.attr,
493	NULL
494};
495
496static const struct attribute_group lp5521_group = {
497	.attrs = lp5521_attributes,
498};
499
500/* Chip specific configurations */
501static struct lp55xx_device_config lp5521_cfg = {
502	.reset = {
503		.addr = LP5521_REG_RESET,
504		.val  = LP5521_RESET,
505	},
506	.enable = {
507		.addr = LP5521_REG_ENABLE,
508		.val  = LP5521_ENABLE_DEFAULT,
509	},
510	.max_channel  = LP5521_MAX_LEDS,
511	.post_init_device   = lp5521_post_init_device,
512	.brightness_fn      = lp5521_led_brightness,
513	.multicolor_brightness_fn = lp5521_multicolor_brightness,
514	.set_led_current    = lp5521_set_led_current,
515	.firmware_cb        = lp5521_firmware_loaded,
516	.run_engine         = lp5521_run_engine,
517	.dev_attr_group     = &lp5521_group,
518};
519
520static int lp5521_probe(struct i2c_client *client)
521{
522	const struct i2c_device_id *id = i2c_client_get_device_id(client);
523	int ret;
524	struct lp55xx_chip *chip;
525	struct lp55xx_led *led;
526	struct lp55xx_platform_data *pdata = dev_get_platdata(&client->dev);
527	struct device_node *np = dev_of_node(&client->dev);
528
529	chip = devm_kzalloc(&client->dev, sizeof(*chip), GFP_KERNEL);
530	if (!chip)
531		return -ENOMEM;
532
533	chip->cfg = &lp5521_cfg;
534
535	if (!pdata) {
536		if (np) {
537			pdata = lp55xx_of_populate_pdata(&client->dev, np,
538							 chip);
539			if (IS_ERR(pdata))
540				return PTR_ERR(pdata);
541		} else {
542			dev_err(&client->dev, "no platform data\n");
543			return -EINVAL;
544		}
545	}
546
547	led = devm_kcalloc(&client->dev,
548			pdata->num_channels, sizeof(*led), GFP_KERNEL);
549	if (!led)
550		return -ENOMEM;
551
552	chip->cl = client;
553	chip->pdata = pdata;
554
555	mutex_init(&chip->lock);
556
557	i2c_set_clientdata(client, led);
558
559	ret = lp55xx_init_device(chip);
560	if (ret)
561		goto err_init;
562
563	dev_info(&client->dev, "%s programmable led chip found\n", id->name);
564
565	ret = lp55xx_register_leds(led, chip);
566	if (ret)
567		goto err_out;
568
569	ret = lp55xx_register_sysfs(chip);
570	if (ret) {
571		dev_err(&client->dev, "registering sysfs failed\n");
572		goto err_out;
573	}
574
575	return 0;
576
577err_out:
578	lp55xx_deinit_device(chip);
579err_init:
580	return ret;
581}
582
583static void lp5521_remove(struct i2c_client *client)
584{
585	struct lp55xx_led *led = i2c_get_clientdata(client);
586	struct lp55xx_chip *chip = led->chip;
587
588	lp5521_stop_all_engines(chip);
589	lp55xx_unregister_sysfs(chip);
590	lp55xx_deinit_device(chip);
591}
592
593static const struct i2c_device_id lp5521_id[] = {
594	{ "lp5521", 0 }, /* Three channel chip */
595	{ }
596};
597MODULE_DEVICE_TABLE(i2c, lp5521_id);
598
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
606static struct i2c_driver lp5521_driver = {
607	.driver = {
608		.name	= "lp5521",
609		.of_match_table = 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");
  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#define LP5521_ENABLE_DEFAULT	\
 85	(LP5521_MASTER_ENABLE | LP5521_LOGARITHMIC_PWM)
 86#define LP5521_ENABLE_RUN_PROGRAM	\
 87	(LP5521_ENABLE_DEFAULT | LP5521_EXEC_RUN)
 88
 89/* Status */
 90#define LP5521_EXT_CLK_USED		0x08
 91
 92/* default R channel current register value */
 93#define LP5521_REG_R_CURR_DEFAULT	0xAF
 94
 95/* Pattern Mode */
 96#define PATTERN_OFF	0
 97
 98struct lp5521_engine {
 99	int		id;
100	u8		mode;
101	u8		prog_page;
102	u8		engine_mask;
103};
104
105struct lp5521_led {
106	int			id;
107	u8			chan_nr;
108	u8			led_current;
109	u8			max_current;
110	struct led_classdev	cdev;
111	struct work_struct	brightness_work;
112	u8			brightness;
113};
114
115struct lp5521_chip {
116	struct lp5521_platform_data *pdata;
117	struct mutex		lock; /* Serialize control */
118	struct i2c_client	*client;
119	struct lp5521_engine	engines[LP5521_MAX_ENGINES];
120	struct lp5521_led	leds[LP5521_MAX_LEDS];
121	u8			num_channels;
122	u8			num_leds;
123};
124
125static inline struct lp5521_led *cdev_to_led(struct led_classdev *cdev)
126{
127	return container_of(cdev, struct lp5521_led, cdev);
128}
129
130static inline struct lp5521_chip *engine_to_lp5521(struct lp5521_engine *engine)
131{
132	return container_of(engine, struct lp5521_chip,
133			    engines[engine->id - 1]);
134}
135
136static inline struct lp5521_chip *led_to_lp5521(struct lp5521_led *led)
137{
138	return container_of(led, struct lp5521_chip,
139			    leds[led->id]);
140}
141
142static void lp5521_led_brightness_work(struct work_struct *work);
143
144static inline int lp5521_write(struct i2c_client *client, u8 reg, u8 value)
145{
146	return i2c_smbus_write_byte_data(client, reg, value);
147}
148
149static int lp5521_read(struct i2c_client *client, u8 reg, u8 *buf)
150{
151	s32 ret;
152
153	ret = i2c_smbus_read_byte_data(client, reg);
154	if (ret < 0)
155		return -EIO;
156
157	*buf = ret;
158	return 0;
159}
160
161static int lp5521_set_engine_mode(struct lp5521_engine *engine, u8 mode)
162{
163	struct lp5521_chip *chip = engine_to_lp5521(engine);
164	struct i2c_client *client = chip->client;
165	int ret;
166	u8 engine_state;
167
168	/* Only transition between RUN and DIRECT mode are handled here */
169	if (mode == LP5521_CMD_LOAD)
170		return 0;
171
172	if (mode == LP5521_CMD_DISABLED)
173		mode = LP5521_CMD_DIRECT;
174
175	ret = lp5521_read(client, LP5521_REG_OP_MODE, &engine_state);
176	if (ret < 0)
177		return ret;
178
179	/* set mode only for this engine */
180	engine_state &= ~(engine->engine_mask);
181	mode &= engine->engine_mask;
182	engine_state |= mode;
183	return lp5521_write(client, LP5521_REG_OP_MODE, engine_state);
184}
185
186static int lp5521_load_program(struct lp5521_engine *eng, const u8 *pattern)
187{
188	struct lp5521_chip *chip = engine_to_lp5521(eng);
189	struct i2c_client *client = chip->client;
190	int ret;
191	int addr;
192	u8 mode;
193
194	/* move current engine to direct mode and remember the state */
195	ret = lp5521_set_engine_mode(eng, LP5521_CMD_DIRECT);
196	if (ret)
197		return ret;
198
199	/* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
200	usleep_range(1000, 2000);
201	ret = lp5521_read(client, LP5521_REG_OP_MODE, &mode);
202	if (ret)
203		return ret;
204
205	/* For loading, all the engines to load mode */
206	lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
207	/* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
208	usleep_range(1000, 2000);
209	lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
210	/* Mode change requires min 500 us delay. 1 - 2 ms  with margin */
211	usleep_range(1000, 2000);
212
213	addr = LP5521_PROG_MEM_BASE + eng->prog_page * LP5521_PROG_MEM_SIZE;
214	i2c_smbus_write_i2c_block_data(client,
215				addr,
216				LP5521_PROG_MEM_SIZE,
217				pattern);
218
219	return lp5521_write(client, LP5521_REG_OP_MODE, mode);
220}
221
222static int lp5521_set_led_current(struct lp5521_chip *chip, int led, u8 curr)
223{
224	return lp5521_write(chip->client,
225		    LP5521_REG_LED_CURRENT_BASE + chip->leds[led].chan_nr,
226		    curr);
227}
228
229static void lp5521_init_engine(struct lp5521_chip *chip)
230{
231	int i;
232	for (i = 0; i < ARRAY_SIZE(chip->engines); i++) {
233		chip->engines[i].id = i + 1;
234		chip->engines[i].engine_mask = LP5521_ENG_MASK_BASE >> (i * 2);
235		chip->engines[i].prog_page = i;
236	}
237}
238
239static int lp5521_configure(struct i2c_client *client)
240{
241	struct lp5521_chip *chip = i2c_get_clientdata(client);
242	int ret;
243	u8 cfg;
244
245	lp5521_init_engine(chip);
246
247	/* Set all PWMs to direct control mode */
248	ret = lp5521_write(client, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
249
250	cfg = chip->pdata->update_config ?
251		: (LP5521_PWRSAVE_EN | LP5521_CP_MODE_AUTO | LP5521_R_TO_BATT);
252	ret |= lp5521_write(client, LP5521_REG_CONFIG, cfg);
253
254	/* Initialize all channels PWM to zero -> leds off */
255	ret |= lp5521_write(client, LP5521_REG_R_PWM, 0);
256	ret |= lp5521_write(client, LP5521_REG_G_PWM, 0);
257	ret |= lp5521_write(client, LP5521_REG_B_PWM, 0);
258
259	/* Set engines are set to run state when OP_MODE enables engines */
260	ret |= lp5521_write(client, LP5521_REG_ENABLE,
261			LP5521_ENABLE_RUN_PROGRAM);
262	/* enable takes 500us. 1 - 2 ms leaves some margin */
263	usleep_range(1000, 2000);
264
265	return ret;
266}
267
268static int lp5521_run_selftest(struct lp5521_chip *chip, char *buf)
269{
270	int ret;
271	u8 status;
272
273	ret = lp5521_read(chip->client, LP5521_REG_STATUS, &status);
274	if (ret < 0)
275		return ret;
276
277	/* Check that ext clock is really in use if requested */
278	if (chip->pdata && chip->pdata->clock_mode == LP5521_CLOCK_EXT)
279		if  ((status & LP5521_EXT_CLK_USED) == 0)
280			return -EIO;
281	return 0;
282}
283
284static void lp5521_set_brightness(struct led_classdev *cdev,
285			     enum led_brightness brightness)
286{
287	struct lp5521_led *led = cdev_to_led(cdev);
288	led->brightness = (u8)brightness;
289	schedule_work(&led->brightness_work);
290}
291
292static void lp5521_led_brightness_work(struct work_struct *work)
293{
294	struct lp5521_led *led = container_of(work,
295					      struct lp5521_led,
296					      brightness_work);
297	struct lp5521_chip *chip = led_to_lp5521(led);
298	struct i2c_client *client = chip->client;
299
300	mutex_lock(&chip->lock);
301	lp5521_write(client, LP5521_REG_LED_PWM_BASE + led->chan_nr,
302		led->brightness);
303	mutex_unlock(&chip->lock);
304}
305
306/* Detect the chip by setting its ENABLE register and reading it back. */
307static int lp5521_detect(struct i2c_client *client)
308{
309	int ret;
310	u8 buf;
311
312	ret = lp5521_write(client, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
313	if (ret)
314		return ret;
315	/* enable takes 500us. 1 - 2 ms leaves some margin */
316	usleep_range(1000, 2000);
317	ret = lp5521_read(client, LP5521_REG_ENABLE, &buf);
318	if (ret)
319		return ret;
320	if (buf != LP5521_ENABLE_DEFAULT)
321		return -ENODEV;
322
323	return 0;
324}
325
326/* Set engine mode and create appropriate sysfs attributes, if required. */
327static int lp5521_set_mode(struct lp5521_engine *engine, u8 mode)
328{
329	int ret = 0;
330
331	/* if in that mode already do nothing, except for run */
332	if (mode == engine->mode && mode != LP5521_CMD_RUN)
333		return 0;
334
335	if (mode == LP5521_CMD_RUN) {
336		ret = lp5521_set_engine_mode(engine, LP5521_CMD_RUN);
337	} else if (mode == LP5521_CMD_LOAD) {
338		lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
339		lp5521_set_engine_mode(engine, LP5521_CMD_LOAD);
340	} else if (mode == LP5521_CMD_DISABLED) {
341		lp5521_set_engine_mode(engine, LP5521_CMD_DISABLED);
342	}
343
344	engine->mode = mode;
345
346	return ret;
347}
348
349static int lp5521_do_store_load(struct lp5521_engine *engine,
350				const char *buf, size_t len)
351{
352	struct lp5521_chip *chip = engine_to_lp5521(engine);
353	struct i2c_client *client = chip->client;
354	int  ret, nrchars, offset = 0, i = 0;
355	char c[3];
356	unsigned cmd;
357	u8 pattern[LP5521_PROGRAM_LENGTH] = {0};
358
359	while ((offset < len - 1) && (i < LP5521_PROGRAM_LENGTH)) {
360		/* separate sscanfs because length is working only for %s */
361		ret = sscanf(buf + offset, "%2s%n ", c, &nrchars);
362		if (ret != 2)
363			goto fail;
364		ret = sscanf(c, "%2x", &cmd);
365		if (ret != 1)
366			goto fail;
367		pattern[i] = (u8)cmd;
368
369		offset += nrchars;
370		i++;
371	}
372
373	/* Each instruction is 16bit long. Check that length is even */
374	if (i % 2)
375		goto fail;
376
377	mutex_lock(&chip->lock);
378	if (engine->mode == LP5521_CMD_LOAD)
379		ret = lp5521_load_program(engine, pattern);
380	else
381		ret = -EINVAL;
382	mutex_unlock(&chip->lock);
383
384	if (ret) {
385		dev_err(&client->dev, "failed loading pattern\n");
386		return ret;
387	}
388
389	return len;
390fail:
391	dev_err(&client->dev, "wrong pattern format\n");
392	return -EINVAL;
393}
394
395static ssize_t store_engine_load(struct device *dev,
396				     struct device_attribute *attr,
397				     const char *buf, size_t len, int nr)
398{
399	struct i2c_client *client = to_i2c_client(dev);
400	struct lp5521_chip *chip = i2c_get_clientdata(client);
401	return lp5521_do_store_load(&chip->engines[nr - 1], buf, len);
402}
403
404#define store_load(nr)							\
405static ssize_t store_engine##nr##_load(struct device *dev,		\
406				     struct device_attribute *attr,	\
407				     const char *buf, size_t len)	\
408{									\
409	return store_engine_load(dev, attr, buf, len, nr);		\
410}
411store_load(1)
412store_load(2)
413store_load(3)
414
415static ssize_t show_engine_mode(struct device *dev,
416				struct device_attribute *attr,
417				char *buf, int nr)
418{
419	struct i2c_client *client = to_i2c_client(dev);
420	struct lp5521_chip *chip = i2c_get_clientdata(client);
421	switch (chip->engines[nr - 1].mode) {
422	case LP5521_CMD_RUN:
423		return sprintf(buf, "run\n");
424	case LP5521_CMD_LOAD:
425		return sprintf(buf, "load\n");
426	case LP5521_CMD_DISABLED:
427		return sprintf(buf, "disabled\n");
428	default:
429		return sprintf(buf, "disabled\n");
430	}
431}
432
433#define show_mode(nr)							\
434static ssize_t show_engine##nr##_mode(struct device *dev,		\
435				    struct device_attribute *attr,	\
436				    char *buf)				\
437{									\
438	return show_engine_mode(dev, attr, buf, nr);			\
439}
440show_mode(1)
441show_mode(2)
442show_mode(3)
443
444static ssize_t store_engine_mode(struct device *dev,
445				 struct device_attribute *attr,
446				 const char *buf, size_t len, int nr)
447{
448	struct i2c_client *client = to_i2c_client(dev);
449	struct lp5521_chip *chip = i2c_get_clientdata(client);
450	struct lp5521_engine *engine = &chip->engines[nr - 1];
451	mutex_lock(&chip->lock);
452
453	if (!strncmp(buf, "run", 3))
454		lp5521_set_mode(engine, LP5521_CMD_RUN);
455	else if (!strncmp(buf, "load", 4))
456		lp5521_set_mode(engine, LP5521_CMD_LOAD);
457	else if (!strncmp(buf, "disabled", 8))
458		lp5521_set_mode(engine, LP5521_CMD_DISABLED);
459
460	mutex_unlock(&chip->lock);
461	return len;
462}
463
464#define store_mode(nr)							\
465static ssize_t store_engine##nr##_mode(struct device *dev,		\
466				     struct device_attribute *attr,	\
467				     const char *buf, size_t len)	\
468{									\
469	return store_engine_mode(dev, attr, buf, len, nr);		\
470}
471store_mode(1)
472store_mode(2)
473store_mode(3)
474
475static ssize_t show_max_current(struct device *dev,
476			    struct device_attribute *attr,
477			    char *buf)
478{
479	struct led_classdev *led_cdev = dev_get_drvdata(dev);
480	struct lp5521_led *led = cdev_to_led(led_cdev);
481
482	return sprintf(buf, "%d\n", led->max_current);
483}
484
485static ssize_t show_current(struct device *dev,
486			    struct device_attribute *attr,
487			    char *buf)
488{
489	struct led_classdev *led_cdev = dev_get_drvdata(dev);
490	struct lp5521_led *led = cdev_to_led(led_cdev);
491
492	return sprintf(buf, "%d\n", led->led_current);
493}
494
495static ssize_t store_current(struct device *dev,
496			     struct device_attribute *attr,
497			     const char *buf, size_t len)
498{
499	struct led_classdev *led_cdev = dev_get_drvdata(dev);
500	struct lp5521_led *led = cdev_to_led(led_cdev);
501	struct lp5521_chip *chip = led_to_lp5521(led);
502	ssize_t ret;
503	unsigned long curr;
504
505	if (kstrtoul(buf, 0, &curr))
506		return -EINVAL;
507
508	if (curr > led->max_current)
509		return -EINVAL;
510
511	mutex_lock(&chip->lock);
512	ret = lp5521_set_led_current(chip, led->id, curr);
513	mutex_unlock(&chip->lock);
514
515	if (ret < 0)
516		return ret;
517
518	led->led_current = (u8)curr;
519
520	return len;
521}
522
523static ssize_t lp5521_selftest(struct device *dev,
524			       struct device_attribute *attr,
525			       char *buf)
526{
527	struct i2c_client *client = to_i2c_client(dev);
528	struct lp5521_chip *chip = i2c_get_clientdata(client);
529	int ret;
530
531	mutex_lock(&chip->lock);
532	ret = lp5521_run_selftest(chip, buf);
533	mutex_unlock(&chip->lock);
534	return sprintf(buf, "%s\n", ret ? "FAIL" : "OK");
535}
536
537static void lp5521_clear_program_memory(struct i2c_client *cl)
538{
539	int i;
540	u8 rgb_mem[] = {
541		LP5521_REG_R_PROG_MEM,
542		LP5521_REG_G_PROG_MEM,
543		LP5521_REG_B_PROG_MEM,
544	};
545
546	for (i = 0; i < ARRAY_SIZE(rgb_mem); i++) {
547		lp5521_write(cl, rgb_mem[i], 0);
548		lp5521_write(cl, rgb_mem[i] + 1, 0);
549	}
550}
551
552static void lp5521_write_program_memory(struct i2c_client *cl,
553				u8 base, u8 *rgb, int size)
554{
555	int i;
556
557	if (!rgb || size <= 0)
558		return;
559
560	for (i = 0; i < size; i++)
561		lp5521_write(cl, base + i, *(rgb + i));
562
563	lp5521_write(cl, base + i, 0);
564	lp5521_write(cl, base + i + 1, 0);
565}
566
567static inline struct lp5521_led_pattern *lp5521_get_pattern
568					(struct lp5521_chip *chip, u8 offset)
569{
570	struct lp5521_led_pattern *ptn;
571	ptn = chip->pdata->patterns + (offset - 1);
572	return ptn;
573}
574
575static void lp5521_run_led_pattern(int mode, struct lp5521_chip *chip)
576{
577	struct lp5521_led_pattern *ptn;
578	struct i2c_client *cl = chip->client;
579	int num_patterns = chip->pdata->num_patterns;
580
581	if (mode > num_patterns || !(chip->pdata->patterns))
582		return;
583
584	if (mode == PATTERN_OFF) {
585		lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_DEFAULT);
586		usleep_range(1000, 2000);
587		lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_DIRECT);
588	} else {
589		ptn = lp5521_get_pattern(chip, mode);
590		if (!ptn)
591			return;
592
593		lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_LOAD);
594		usleep_range(1000, 2000);
595
596		lp5521_clear_program_memory(cl);
597
598		lp5521_write_program_memory(cl, LP5521_REG_R_PROG_MEM,
599					ptn->r, ptn->size_r);
600		lp5521_write_program_memory(cl, LP5521_REG_G_PROG_MEM,
601					ptn->g, ptn->size_g);
602		lp5521_write_program_memory(cl, LP5521_REG_B_PROG_MEM,
603					ptn->b, ptn->size_b);
604
605		lp5521_write(cl, LP5521_REG_OP_MODE, LP5521_CMD_RUN);
606		usleep_range(1000, 2000);
607		lp5521_write(cl, LP5521_REG_ENABLE, LP5521_ENABLE_RUN_PROGRAM);
608	}
609}
610
611static ssize_t store_led_pattern(struct device *dev,
612				struct device_attribute *attr,
613				const char *buf, size_t len)
614{
615	struct lp5521_chip *chip = i2c_get_clientdata(to_i2c_client(dev));
616	unsigned long val;
617	int ret;
618
619	ret = strict_strtoul(buf, 16, &val);
620	if (ret)
621		return ret;
622
623	lp5521_run_led_pattern(val, chip);
624
625	return len;
626}
627
628/* led class device attributes */
629static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, show_current, store_current);
630static DEVICE_ATTR(max_current, S_IRUGO , show_max_current, NULL);
631
632static struct attribute *lp5521_led_attributes[] = {
633	&dev_attr_led_current.attr,
634	&dev_attr_max_current.attr,
635	NULL,
636};
637
638static struct attribute_group lp5521_led_attribute_group = {
639	.attrs = lp5521_led_attributes
640};
641
642/* device attributes */
643static DEVICE_ATTR(engine1_mode, S_IRUGO | S_IWUSR,
644		   show_engine1_mode, store_engine1_mode);
645static DEVICE_ATTR(engine2_mode, S_IRUGO | S_IWUSR,
646		   show_engine2_mode, store_engine2_mode);
647static DEVICE_ATTR(engine3_mode, S_IRUGO | S_IWUSR,
648		   show_engine3_mode, store_engine3_mode);
649static DEVICE_ATTR(engine1_load, S_IWUSR, NULL, store_engine1_load);
650static DEVICE_ATTR(engine2_load, S_IWUSR, NULL, store_engine2_load);
651static DEVICE_ATTR(engine3_load, S_IWUSR, NULL, store_engine3_load);
652static DEVICE_ATTR(selftest, S_IRUGO, lp5521_selftest, NULL);
653static DEVICE_ATTR(led_pattern, S_IWUSR, NULL, store_led_pattern);
654
655static struct attribute *lp5521_attributes[] = {
656	&dev_attr_engine1_mode.attr,
657	&dev_attr_engine2_mode.attr,
658	&dev_attr_engine3_mode.attr,
659	&dev_attr_selftest.attr,
660	&dev_attr_engine1_load.attr,
661	&dev_attr_engine2_load.attr,
662	&dev_attr_engine3_load.attr,
663	&dev_attr_led_pattern.attr,
664	NULL
665};
666
667static const struct attribute_group lp5521_group = {
668	.attrs = lp5521_attributes,
669};
670
671static int lp5521_register_sysfs(struct i2c_client *client)
672{
673	struct device *dev = &client->dev;
674	return sysfs_create_group(&dev->kobj, &lp5521_group);
675}
676
677static void lp5521_unregister_sysfs(struct i2c_client *client)
678{
679	struct lp5521_chip *chip = i2c_get_clientdata(client);
680	struct device *dev = &client->dev;
681	int i;
682
683	sysfs_remove_group(&dev->kobj, &lp5521_group);
684
685	for (i = 0; i < chip->num_leds; i++)
686		sysfs_remove_group(&chip->leds[i].cdev.dev->kobj,
687				&lp5521_led_attribute_group);
688}
689
690static int __devinit lp5521_init_led(struct lp5521_led *led,
691				struct i2c_client *client,
692				int chan, struct lp5521_platform_data *pdata)
693{
694	struct device *dev = &client->dev;
695	char name[32];
696	int res;
697
698	if (chan >= LP5521_MAX_LEDS)
699		return -EINVAL;
700
701	if (pdata->led_config[chan].led_current == 0)
702		return 0;
703
704	led->led_current = pdata->led_config[chan].led_current;
705	led->max_current = pdata->led_config[chan].max_current;
706	led->chan_nr = pdata->led_config[chan].chan_nr;
707
708	if (led->chan_nr >= LP5521_MAX_LEDS) {
709		dev_err(dev, "Use channel numbers between 0 and %d\n",
710			LP5521_MAX_LEDS - 1);
711		return -EINVAL;
712	}
713
714	led->cdev.brightness_set = lp5521_set_brightness;
715	if (pdata->led_config[chan].name) {
716		led->cdev.name = pdata->led_config[chan].name;
717	} else {
718		snprintf(name, sizeof(name), "%s:channel%d",
719			pdata->label ?: client->name, chan);
720		led->cdev.name = name;
721	}
722
723	res = led_classdev_register(dev, &led->cdev);
724	if (res < 0) {
725		dev_err(dev, "couldn't register led on channel %d\n", chan);
726		return res;
727	}
728
729	res = sysfs_create_group(&led->cdev.dev->kobj,
730			&lp5521_led_attribute_group);
731	if (res < 0) {
732		dev_err(dev, "couldn't register current attribute\n");
733		led_classdev_unregister(&led->cdev);
734		return res;
735	}
736	return 0;
737}
738
739static int __devinit lp5521_probe(struct i2c_client *client,
740			const struct i2c_device_id *id)
741{
742	struct lp5521_chip		*chip;
743	struct lp5521_platform_data	*pdata;
744	int ret, i, led;
745	u8 buf;
746
747	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
748	if (!chip)
749		return -ENOMEM;
750
751	i2c_set_clientdata(client, chip);
752	chip->client = client;
753
754	pdata = client->dev.platform_data;
755
756	if (!pdata) {
757		dev_err(&client->dev, "no platform data\n");
758		ret = -EINVAL;
759		goto fail1;
760	}
761
762	mutex_init(&chip->lock);
763
764	chip->pdata   = pdata;
765
766	if (pdata->setup_resources) {
767		ret = pdata->setup_resources();
768		if (ret < 0)
769			goto fail1;
770	}
771
772	if (pdata->enable) {
773		pdata->enable(0);
774		usleep_range(1000, 2000); /* Keep enable down at least 1ms */
775		pdata->enable(1);
776		usleep_range(1000, 2000); /* 500us abs min. */
777	}
778
779	lp5521_write(client, LP5521_REG_RESET, 0xff);
780	usleep_range(10000, 20000); /*
781				     * Exact value is not available. 10 - 20ms
782				     * appears to be enough for reset.
783				     */
784
785	/*
786	 * Make sure that the chip is reset by reading back the r channel
787	 * current reg. This is dummy read is required on some platforms -
788	 * otherwise further access to the R G B channels in the
789	 * LP5521_REG_ENABLE register will not have any effect - strange!
790	 */
791	ret = lp5521_read(client, LP5521_REG_R_CURRENT, &buf);
792	if (ret || buf != LP5521_REG_R_CURR_DEFAULT) {
793		dev_err(&client->dev, "error in resetting chip\n");
794		goto fail2;
795	}
796	usleep_range(10000, 20000);
797
798	ret = lp5521_detect(client);
799
800	if (ret) {
801		dev_err(&client->dev, "Chip not found\n");
802		goto fail2;
803	}
804
805	dev_info(&client->dev, "%s programmable led chip found\n", id->name);
806
807	ret = lp5521_configure(client);
808	if (ret < 0) {
809		dev_err(&client->dev, "error configuring chip\n");
810		goto fail2;
811	}
812
813	/* Initialize leds */
814	chip->num_channels = pdata->num_channels;
815	chip->num_leds = 0;
816	led = 0;
817	for (i = 0; i < pdata->num_channels; i++) {
818		/* Do not initialize channels that are not connected */
819		if (pdata->led_config[i].led_current == 0)
820			continue;
821
822		ret = lp5521_init_led(&chip->leds[led], client, i, pdata);
823		if (ret) {
824			dev_err(&client->dev, "error initializing leds\n");
825			goto fail3;
826		}
827		chip->num_leds++;
828
829		chip->leds[led].id = led;
830		/* Set initial LED current */
831		lp5521_set_led_current(chip, led,
832				chip->leds[led].led_current);
833
834		INIT_WORK(&(chip->leds[led].brightness_work),
835			lp5521_led_brightness_work);
836
837		led++;
838	}
839
840	ret = lp5521_register_sysfs(client);
841	if (ret) {
842		dev_err(&client->dev, "registering sysfs failed\n");
843		goto fail3;
844	}
845	return ret;
846fail3:
847	for (i = 0; i < chip->num_leds; i++) {
848		led_classdev_unregister(&chip->leds[i].cdev);
849		cancel_work_sync(&chip->leds[i].brightness_work);
850	}
851fail2:
852	if (pdata->enable)
853		pdata->enable(0);
854	if (pdata->release_resources)
855		pdata->release_resources();
856fail1:
857	kfree(chip);
858	return ret;
859}
860
861static int __devexit lp5521_remove(struct i2c_client *client)
862{
863	struct lp5521_chip *chip = i2c_get_clientdata(client);
864	int i;
865
866	lp5521_run_led_pattern(PATTERN_OFF, chip);
867	lp5521_unregister_sysfs(client);
868
869	for (i = 0; i < chip->num_leds; i++) {
870		led_classdev_unregister(&chip->leds[i].cdev);
871		cancel_work_sync(&chip->leds[i].brightness_work);
872	}
873
874	if (chip->pdata->enable)
875		chip->pdata->enable(0);
876	if (chip->pdata->release_resources)
877		chip->pdata->release_resources();
878	kfree(chip);
879	return 0;
880}
881
882static const struct i2c_device_id lp5521_id[] = {
883	{ "lp5521", 0 }, /* Three channel chip */
884	{ }
885};
886MODULE_DEVICE_TABLE(i2c, lp5521_id);
887
888static struct i2c_driver lp5521_driver = {
889	.driver = {
890		.name	= "lp5521",
891	},
892	.probe		= lp5521_probe,
893	.remove		= __devexit_p(lp5521_remove),
894	.id_table	= lp5521_id,
895};
896
897module_i2c_driver(lp5521_driver);
898
899MODULE_AUTHOR("Mathias Nyman, Yuri Zaporozhets, Samu Onkalo");
900MODULE_DESCRIPTION("LP5521 LED engine");
901MODULE_LICENSE("GPL v2");