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v6.2
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LP5521/LP5523/LP55231/LP5562 Common Driver
  4 *
  5 * Copyright 2012 Texas Instruments
  6 *
  7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
  8 *
  9 * Derived from leds-lp5521.c, leds-lp5523.c
 10 */
 11
 12#include <linux/clk.h>
 13#include <linux/delay.h>
 14#include <linux/firmware.h>
 15#include <linux/i2c.h>
 16#include <linux/leds.h>
 17#include <linux/module.h>
 18#include <linux/platform_data/leds-lp55xx.h>
 19#include <linux/slab.h>
 20#include <linux/gpio/consumer.h>
 
 21
 22#include "leds-lp55xx-common.h"
 23
 24/* External clock rate */
 25#define LP55XX_CLK_32K			32768
 26
 27static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
 28{
 29	return container_of(cdev, struct lp55xx_led, cdev);
 30}
 31
 32static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
 33{
 34	return cdev_to_lp55xx_led(dev_get_drvdata(dev));
 35}
 36
 37static struct lp55xx_led *mcled_cdev_to_led(struct led_classdev_mc *mc_cdev)
 38{
 39	return container_of(mc_cdev, struct lp55xx_led, mc_cdev);
 40}
 41
 42static void lp55xx_reset_device(struct lp55xx_chip *chip)
 43{
 44	struct lp55xx_device_config *cfg = chip->cfg;
 45	u8 addr = cfg->reset.addr;
 46	u8 val  = cfg->reset.val;
 47
 48	/* no error checking here because no ACK from the device after reset */
 49	lp55xx_write(chip, addr, val);
 50}
 51
 52static int lp55xx_detect_device(struct lp55xx_chip *chip)
 53{
 54	struct lp55xx_device_config *cfg = chip->cfg;
 55	u8 addr = cfg->enable.addr;
 56	u8 val  = cfg->enable.val;
 57	int ret;
 58
 59	ret = lp55xx_write(chip, addr, val);
 60	if (ret)
 61		return ret;
 62
 63	usleep_range(1000, 2000);
 64
 65	ret = lp55xx_read(chip, addr, &val);
 66	if (ret)
 67		return ret;
 68
 69	if (val != cfg->enable.val)
 70		return -ENODEV;
 71
 72	return 0;
 73}
 74
 75static int lp55xx_post_init_device(struct lp55xx_chip *chip)
 76{
 77	struct lp55xx_device_config *cfg = chip->cfg;
 78
 79	if (!cfg->post_init_device)
 80		return 0;
 81
 82	return cfg->post_init_device(chip);
 83}
 84
 85static ssize_t led_current_show(struct device *dev,
 86			    struct device_attribute *attr,
 87			    char *buf)
 88{
 89	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
 90
 91	return sysfs_emit(buf, "%d\n", led->led_current);
 92}
 93
 94static ssize_t led_current_store(struct device *dev,
 95			     struct device_attribute *attr,
 96			     const char *buf, size_t len)
 97{
 98	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
 99	struct lp55xx_chip *chip = led->chip;
100	unsigned long curr;
101
102	if (kstrtoul(buf, 0, &curr))
103		return -EINVAL;
104
105	if (curr > led->max_current)
106		return -EINVAL;
107
108	if (!chip->cfg->set_led_current)
109		return len;
110
111	mutex_lock(&chip->lock);
112	chip->cfg->set_led_current(led, (u8)curr);
113	mutex_unlock(&chip->lock);
114
115	return len;
116}
117
118static ssize_t max_current_show(struct device *dev,
119			    struct device_attribute *attr,
120			    char *buf)
121{
122	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
123
124	return sysfs_emit(buf, "%d\n", led->max_current);
125}
126
127static DEVICE_ATTR_RW(led_current);
128static DEVICE_ATTR_RO(max_current);
 
129
130static struct attribute *lp55xx_led_attrs[] = {
131	&dev_attr_led_current.attr,
132	&dev_attr_max_current.attr,
133	NULL,
134};
135ATTRIBUTE_GROUPS(lp55xx_led);
136
137static int lp55xx_set_mc_brightness(struct led_classdev *cdev,
138				    enum led_brightness brightness)
139{
140	struct led_classdev_mc *mc_dev = lcdev_to_mccdev(cdev);
141	struct lp55xx_led *led = mcled_cdev_to_led(mc_dev);
142	struct lp55xx_device_config *cfg = led->chip->cfg;
143
144	led_mc_calc_color_components(&led->mc_cdev, brightness);
145	return cfg->multicolor_brightness_fn(led);
146
147}
148
149static int lp55xx_set_brightness(struct led_classdev *cdev,
150			     enum led_brightness brightness)
151{
152	struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
153	struct lp55xx_device_config *cfg = led->chip->cfg;
154
155	led->brightness = (u8)brightness;
156	return cfg->brightness_fn(led);
157}
158
159static int lp55xx_init_led(struct lp55xx_led *led,
160			struct lp55xx_chip *chip, int chan)
161{
162	struct lp55xx_platform_data *pdata = chip->pdata;
163	struct lp55xx_device_config *cfg = chip->cfg;
164	struct device *dev = &chip->cl->dev;
165	int max_channel = cfg->max_channel;
166	struct mc_subled *mc_led_info;
167	struct led_classdev *led_cdev;
168	char name[32];
169	int i;
170	int ret;
 
171
172	if (chan >= max_channel) {
173		dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
174		return -EINVAL;
175	}
176
177	if (pdata->led_config[chan].led_current == 0)
178		return 0;
179
180	if (pdata->led_config[chan].name) {
181		led->cdev.name = pdata->led_config[chan].name;
182	} else {
183		snprintf(name, sizeof(name), "%s:channel%d",
184			pdata->label ? : chip->cl->name, chan);
185		led->cdev.name = name;
186	}
187
188	if (pdata->led_config[chan].num_colors > 1) {
189		mc_led_info = devm_kcalloc(dev,
190					   pdata->led_config[chan].num_colors,
191					   sizeof(*mc_led_info), GFP_KERNEL);
192		if (!mc_led_info)
193			return -ENOMEM;
194
195		led_cdev = &led->mc_cdev.led_cdev;
196		led_cdev->name = led->cdev.name;
197		led_cdev->brightness_set_blocking = lp55xx_set_mc_brightness;
198		led->mc_cdev.num_colors = pdata->led_config[chan].num_colors;
199		for (i = 0; i < led->mc_cdev.num_colors; i++) {
200			mc_led_info[i].color_index =
201				pdata->led_config[chan].color_id[i];
202			mc_led_info[i].channel =
203					pdata->led_config[chan].output_num[i];
204		}
205
206		led->mc_cdev.subled_info = mc_led_info;
207	} else {
208		led->cdev.brightness_set_blocking = lp55xx_set_brightness;
209	}
210
211	led->cdev.groups = lp55xx_led_groups;
212	led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
213	led->led_current = pdata->led_config[chan].led_current;
214	led->max_current = pdata->led_config[chan].max_current;
215	led->chan_nr = pdata->led_config[chan].chan_nr;
 
216
217	if (led->chan_nr >= max_channel) {
218		dev_err(dev, "Use channel numbers between 0 and %d\n",
219			max_channel - 1);
220		return -EINVAL;
221	}
222
223	if (pdata->led_config[chan].num_colors > 1)
224		ret = devm_led_classdev_multicolor_register(dev, &led->mc_cdev);
225	else
226		ret = devm_led_classdev_register(dev, &led->cdev);
 
 
 
 
 
 
227
 
228	if (ret) {
229		dev_err(dev, "led register err: %d\n", ret);
230		return ret;
231	}
232
233	return 0;
234}
235
236static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
237{
238	struct lp55xx_chip *chip = context;
239	struct device *dev = &chip->cl->dev;
240	enum lp55xx_engine_index idx = chip->engine_idx;
241
242	if (!fw) {
243		dev_err(dev, "firmware request failed\n");
244		return;
245	}
246
247	/* handling firmware data is chip dependent */
248	mutex_lock(&chip->lock);
249
250	chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
251	chip->fw = fw;
252	if (chip->cfg->firmware_cb)
253		chip->cfg->firmware_cb(chip);
254
255	mutex_unlock(&chip->lock);
256
257	/* firmware should be released for other channel use */
258	release_firmware(chip->fw);
259	chip->fw = NULL;
260}
261
262static int lp55xx_request_firmware(struct lp55xx_chip *chip)
263{
264	const char *name = chip->cl->name;
265	struct device *dev = &chip->cl->dev;
266
267	return request_firmware_nowait(THIS_MODULE, false, name, dev,
268				GFP_KERNEL, chip, lp55xx_firmware_loaded);
269}
270
271static ssize_t select_engine_show(struct device *dev,
272			    struct device_attribute *attr,
273			    char *buf)
274{
275	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
276	struct lp55xx_chip *chip = led->chip;
277
278	return sprintf(buf, "%d\n", chip->engine_idx);
279}
280
281static ssize_t select_engine_store(struct device *dev,
282			     struct device_attribute *attr,
283			     const char *buf, size_t len)
284{
285	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
286	struct lp55xx_chip *chip = led->chip;
287	unsigned long val;
288	int ret;
289
290	if (kstrtoul(buf, 0, &val))
291		return -EINVAL;
292
293	/* select the engine to be run */
294
295	switch (val) {
296	case LP55XX_ENGINE_1:
297	case LP55XX_ENGINE_2:
298	case LP55XX_ENGINE_3:
299		mutex_lock(&chip->lock);
300		chip->engine_idx = val;
301		ret = lp55xx_request_firmware(chip);
302		mutex_unlock(&chip->lock);
303		break;
304	default:
305		dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
306		return -EINVAL;
307	}
308
309	if (ret) {
310		dev_err(dev, "request firmware err: %d\n", ret);
311		return ret;
312	}
313
314	return len;
315}
316
317static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
318{
319	if (chip->cfg->run_engine)
320		chip->cfg->run_engine(chip, start);
321}
322
323static ssize_t run_engine_store(struct device *dev,
324			     struct device_attribute *attr,
325			     const char *buf, size_t len)
326{
327	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
328	struct lp55xx_chip *chip = led->chip;
329	unsigned long val;
330
331	if (kstrtoul(buf, 0, &val))
332		return -EINVAL;
333
334	/* run or stop the selected engine */
335
336	if (val <= 0) {
337		lp55xx_run_engine(chip, false);
338		return len;
339	}
340
341	mutex_lock(&chip->lock);
342	lp55xx_run_engine(chip, true);
343	mutex_unlock(&chip->lock);
344
345	return len;
346}
347
348static DEVICE_ATTR_RW(select_engine);
349static DEVICE_ATTR_WO(run_engine);
 
350
351static struct attribute *lp55xx_engine_attributes[] = {
352	&dev_attr_select_engine.attr,
353	&dev_attr_run_engine.attr,
354	NULL,
355};
356
357static const struct attribute_group lp55xx_engine_attr_group = {
358	.attrs = lp55xx_engine_attributes,
359};
360
361int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
362{
363	return i2c_smbus_write_byte_data(chip->cl, reg, val);
364}
365EXPORT_SYMBOL_GPL(lp55xx_write);
366
367int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
368{
369	s32 ret;
370
371	ret = i2c_smbus_read_byte_data(chip->cl, reg);
372	if (ret < 0)
373		return ret;
374
375	*val = ret;
376	return 0;
377}
378EXPORT_SYMBOL_GPL(lp55xx_read);
379
380int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
381{
382	int ret;
383	u8 tmp;
384
385	ret = lp55xx_read(chip, reg, &tmp);
386	if (ret)
387		return ret;
388
389	tmp &= ~mask;
390	tmp |= val & mask;
391
392	return lp55xx_write(chip, reg, tmp);
393}
394EXPORT_SYMBOL_GPL(lp55xx_update_bits);
395
396bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
397{
398	struct clk *clk;
399	int err;
400
401	clk = devm_clk_get(&chip->cl->dev, "32k_clk");
402	if (IS_ERR(clk))
403		goto use_internal_clk;
404
405	err = clk_prepare_enable(clk);
406	if (err)
407		goto use_internal_clk;
408
409	if (clk_get_rate(clk) != LP55XX_CLK_32K) {
410		clk_disable_unprepare(clk);
411		goto use_internal_clk;
412	}
413
414	dev_info(&chip->cl->dev, "%dHz external clock used\n",	LP55XX_CLK_32K);
415
416	chip->clk = clk;
417	return true;
418
419use_internal_clk:
420	dev_info(&chip->cl->dev, "internal clock used\n");
421	return false;
422}
423EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);
424
425int lp55xx_init_device(struct lp55xx_chip *chip)
426{
427	struct lp55xx_platform_data *pdata;
428	struct lp55xx_device_config *cfg;
429	struct device *dev = &chip->cl->dev;
430	int ret = 0;
431
432	WARN_ON(!chip);
433
434	pdata = chip->pdata;
435	cfg = chip->cfg;
436
437	if (!pdata || !cfg)
438		return -EINVAL;
439
440	if (pdata->enable_gpiod) {
441		gpiod_direction_output(pdata->enable_gpiod, 0);
 
 
 
 
 
 
442
443		gpiod_set_consumer_name(pdata->enable_gpiod, "LP55xx enable");
444		gpiod_set_value(pdata->enable_gpiod, 0);
445		usleep_range(1000, 2000); /* Keep enable down at least 1ms */
446		gpiod_set_value(pdata->enable_gpiod, 1);
447		usleep_range(1000, 2000); /* 500us abs min. */
448	}
449
450	lp55xx_reset_device(chip);
451
452	/*
453	 * Exact value is not available. 10 - 20ms
454	 * appears to be enough for reset.
455	 */
456	usleep_range(10000, 20000);
457
458	ret = lp55xx_detect_device(chip);
459	if (ret) {
460		dev_err(dev, "device detection err: %d\n", ret);
461		goto err;
462	}
463
464	/* chip specific initialization */
465	ret = lp55xx_post_init_device(chip);
466	if (ret) {
467		dev_err(dev, "post init device err: %d\n", ret);
468		goto err_post_init;
469	}
470
471	return 0;
472
473err_post_init:
474	lp55xx_deinit_device(chip);
475err:
476	return ret;
477}
478EXPORT_SYMBOL_GPL(lp55xx_init_device);
479
480void lp55xx_deinit_device(struct lp55xx_chip *chip)
481{
482	struct lp55xx_platform_data *pdata = chip->pdata;
483
484	if (chip->clk)
485		clk_disable_unprepare(chip->clk);
486
487	if (pdata->enable_gpiod)
488		gpiod_set_value(pdata->enable_gpiod, 0);
489}
490EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
491
492int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
493{
494	struct lp55xx_platform_data *pdata = chip->pdata;
495	struct lp55xx_device_config *cfg = chip->cfg;
496	int num_channels = pdata->num_channels;
497	struct lp55xx_led *each;
498	u8 led_current;
499	int ret;
500	int i;
501
502	if (!cfg->brightness_fn) {
503		dev_err(&chip->cl->dev, "empty brightness configuration\n");
504		return -EINVAL;
505	}
506
507	for (i = 0; i < num_channels; i++) {
508
509		/* do not initialize channels that are not connected */
510		if (pdata->led_config[i].led_current == 0)
511			continue;
512
513		led_current = pdata->led_config[i].led_current;
514		each = led + i;
515		ret = lp55xx_init_led(each, chip, i);
516		if (ret)
517			goto err_init_led;
518
519		chip->num_leds++;
520		each->chip = chip;
521
522		/* setting led current at each channel */
523		if (cfg->set_led_current)
524			cfg->set_led_current(each, led_current);
525	}
526
527	return 0;
528
529err_init_led:
 
530	return ret;
531}
532EXPORT_SYMBOL_GPL(lp55xx_register_leds);
533
 
 
 
 
 
 
 
 
 
 
 
 
534int lp55xx_register_sysfs(struct lp55xx_chip *chip)
535{
536	struct device *dev = &chip->cl->dev;
537	struct lp55xx_device_config *cfg = chip->cfg;
538	int ret;
539
540	if (!cfg->run_engine || !cfg->firmware_cb)
541		goto dev_specific_attrs;
542
543	ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
544	if (ret)
545		return ret;
546
547dev_specific_attrs:
548	return cfg->dev_attr_group ?
549		sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
550}
551EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
552
553void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
554{
555	struct device *dev = &chip->cl->dev;
556	struct lp55xx_device_config *cfg = chip->cfg;
557
558	if (cfg->dev_attr_group)
559		sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);
560
561	sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
562}
563EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);
564
565static int lp55xx_parse_common_child(struct device_node *np,
566				     struct lp55xx_led_config *cfg,
567				     int led_number, int *chan_nr)
568{
569	int ret;
570
571	of_property_read_string(np, "chan-name",
572				&cfg[led_number].name);
573	of_property_read_u8(np, "led-cur",
574			    &cfg[led_number].led_current);
575	of_property_read_u8(np, "max-cur",
576			    &cfg[led_number].max_current);
577
578	ret = of_property_read_u32(np, "reg", chan_nr);
579	if (ret)
580		return ret;
581
582	if (*chan_nr < 0 || *chan_nr > cfg->max_channel)
583		return -EINVAL;
584
585	return 0;
586}
587
588static int lp55xx_parse_multi_led_child(struct device_node *child,
589					 struct lp55xx_led_config *cfg,
590					 int child_number, int color_number)
591{
592	int chan_nr, color_id, ret;
593
594	ret = lp55xx_parse_common_child(child, cfg, child_number, &chan_nr);
595	if (ret)
596		return ret;
597
598	ret = of_property_read_u32(child, "color", &color_id);
599	if (ret)
600		return ret;
601
602	cfg[child_number].color_id[color_number] = color_id;
603	cfg[child_number].output_num[color_number] = chan_nr;
604
605	return 0;
606}
607
608static int lp55xx_parse_multi_led(struct device_node *np,
609				  struct lp55xx_led_config *cfg,
610				  int child_number)
611{
612	struct device_node *child;
613	int num_colors = 0, ret;
614
615	for_each_available_child_of_node(np, child) {
616		ret = lp55xx_parse_multi_led_child(child, cfg, child_number,
617						   num_colors);
618		if (ret) {
619			of_node_put(child);
620			return ret;
621		}
622		num_colors++;
623	}
624
625	cfg[child_number].num_colors = num_colors;
626
627	return 0;
628}
629
630static int lp55xx_parse_logical_led(struct device_node *np,
631				   struct lp55xx_led_config *cfg,
632				   int child_number)
633{
634	int led_color, ret;
635	int chan_nr = 0;
636
637	cfg[child_number].default_trigger =
638		of_get_property(np, "linux,default-trigger", NULL);
639
640	ret = of_property_read_u32(np, "color", &led_color);
641	if (ret)
642		return ret;
643
644	if (led_color == LED_COLOR_ID_RGB)
645		return lp55xx_parse_multi_led(np, cfg, child_number);
646
647	ret =  lp55xx_parse_common_child(np, cfg, child_number, &chan_nr);
648	if (ret < 0)
649		return ret;
650
651	cfg[child_number].chan_nr = chan_nr;
652
653	return ret;
654}
655
656struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
657						      struct device_node *np,
658						      struct lp55xx_chip *chip)
659{
660	struct device_node *child;
661	struct lp55xx_platform_data *pdata;
662	struct lp55xx_led_config *cfg;
663	int num_channels;
664	int i = 0;
665	int ret;
666
667	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
668	if (!pdata)
669		return ERR_PTR(-ENOMEM);
670
671	num_channels = of_get_available_child_count(np);
672	if (num_channels == 0) {
673		dev_err(dev, "no LED channels\n");
674		return ERR_PTR(-EINVAL);
675	}
676
677	cfg = devm_kcalloc(dev, num_channels, sizeof(*cfg), GFP_KERNEL);
678	if (!cfg)
679		return ERR_PTR(-ENOMEM);
680
681	pdata->led_config = &cfg[0];
682	pdata->num_channels = num_channels;
683	cfg->max_channel = chip->cfg->max_channel;
684
685	for_each_available_child_of_node(np, child) {
686		ret = lp55xx_parse_logical_led(child, cfg, i);
687		if (ret) {
688			of_node_put(child);
689			return ERR_PTR(-EINVAL);
690		}
 
 
 
691		i++;
692	}
693
694	of_property_read_string(np, "label", &pdata->label);
695	of_property_read_u8(np, "clock-mode", &pdata->clock_mode);
696
697	pdata->enable_gpiod = devm_gpiod_get_optional(dev, "enable",
698						      GPIOD_ASIS);
699	if (IS_ERR(pdata->enable_gpiod))
700		return ERR_CAST(pdata->enable_gpiod);
701
702	/* LP8501 specific */
703	of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);
704
705	return pdata;
706}
707EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);
708
709MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
710MODULE_DESCRIPTION("LP55xx Common Driver");
711MODULE_LICENSE("GPL");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * LP5521/LP5523/LP55231/LP5562 Common Driver
  4 *
  5 * Copyright 2012 Texas Instruments
  6 *
  7 * Author: Milo(Woogyom) Kim <milo.kim@ti.com>
  8 *
  9 * Derived from leds-lp5521.c, leds-lp5523.c
 10 */
 11
 12#include <linux/clk.h>
 13#include <linux/delay.h>
 14#include <linux/firmware.h>
 15#include <linux/i2c.h>
 16#include <linux/leds.h>
 17#include <linux/module.h>
 18#include <linux/platform_data/leds-lp55xx.h>
 19#include <linux/slab.h>
 20#include <linux/gpio.h>
 21#include <linux/of_gpio.h>
 22
 23#include "leds-lp55xx-common.h"
 24
 25/* External clock rate */
 26#define LP55XX_CLK_32K			32768
 27
 28static struct lp55xx_led *cdev_to_lp55xx_led(struct led_classdev *cdev)
 29{
 30	return container_of(cdev, struct lp55xx_led, cdev);
 31}
 32
 33static struct lp55xx_led *dev_to_lp55xx_led(struct device *dev)
 34{
 35	return cdev_to_lp55xx_led(dev_get_drvdata(dev));
 36}
 37
 
 
 
 
 
 38static void lp55xx_reset_device(struct lp55xx_chip *chip)
 39{
 40	struct lp55xx_device_config *cfg = chip->cfg;
 41	u8 addr = cfg->reset.addr;
 42	u8 val  = cfg->reset.val;
 43
 44	/* no error checking here because no ACK from the device after reset */
 45	lp55xx_write(chip, addr, val);
 46}
 47
 48static int lp55xx_detect_device(struct lp55xx_chip *chip)
 49{
 50	struct lp55xx_device_config *cfg = chip->cfg;
 51	u8 addr = cfg->enable.addr;
 52	u8 val  = cfg->enable.val;
 53	int ret;
 54
 55	ret = lp55xx_write(chip, addr, val);
 56	if (ret)
 57		return ret;
 58
 59	usleep_range(1000, 2000);
 60
 61	ret = lp55xx_read(chip, addr, &val);
 62	if (ret)
 63		return ret;
 64
 65	if (val != cfg->enable.val)
 66		return -ENODEV;
 67
 68	return 0;
 69}
 70
 71static int lp55xx_post_init_device(struct lp55xx_chip *chip)
 72{
 73	struct lp55xx_device_config *cfg = chip->cfg;
 74
 75	if (!cfg->post_init_device)
 76		return 0;
 77
 78	return cfg->post_init_device(chip);
 79}
 80
 81static ssize_t lp55xx_show_current(struct device *dev,
 82			    struct device_attribute *attr,
 83			    char *buf)
 84{
 85	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
 86
 87	return scnprintf(buf, PAGE_SIZE, "%d\n", led->led_current);
 88}
 89
 90static ssize_t lp55xx_store_current(struct device *dev,
 91			     struct device_attribute *attr,
 92			     const char *buf, size_t len)
 93{
 94	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
 95	struct lp55xx_chip *chip = led->chip;
 96	unsigned long curr;
 97
 98	if (kstrtoul(buf, 0, &curr))
 99		return -EINVAL;
100
101	if (curr > led->max_current)
102		return -EINVAL;
103
104	if (!chip->cfg->set_led_current)
105		return len;
106
107	mutex_lock(&chip->lock);
108	chip->cfg->set_led_current(led, (u8)curr);
109	mutex_unlock(&chip->lock);
110
111	return len;
112}
113
114static ssize_t lp55xx_show_max_current(struct device *dev,
115			    struct device_attribute *attr,
116			    char *buf)
117{
118	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
119
120	return scnprintf(buf, PAGE_SIZE, "%d\n", led->max_current);
121}
122
123static DEVICE_ATTR(led_current, S_IRUGO | S_IWUSR, lp55xx_show_current,
124		lp55xx_store_current);
125static DEVICE_ATTR(max_current, S_IRUGO , lp55xx_show_max_current, NULL);
126
127static struct attribute *lp55xx_led_attrs[] = {
128	&dev_attr_led_current.attr,
129	&dev_attr_max_current.attr,
130	NULL,
131};
132ATTRIBUTE_GROUPS(lp55xx_led);
133
 
 
 
 
 
 
 
 
 
 
 
 
134static int lp55xx_set_brightness(struct led_classdev *cdev,
135			     enum led_brightness brightness)
136{
137	struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
138	struct lp55xx_device_config *cfg = led->chip->cfg;
139
140	led->brightness = (u8)brightness;
141	return cfg->brightness_fn(led);
142}
143
144static int lp55xx_init_led(struct lp55xx_led *led,
145			struct lp55xx_chip *chip, int chan)
146{
147	struct lp55xx_platform_data *pdata = chip->pdata;
148	struct lp55xx_device_config *cfg = chip->cfg;
149	struct device *dev = &chip->cl->dev;
 
 
 
150	char name[32];
 
151	int ret;
152	int max_channel = cfg->max_channel;
153
154	if (chan >= max_channel) {
155		dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
156		return -EINVAL;
157	}
158
159	if (pdata->led_config[chan].led_current == 0)
160		return 0;
161
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
162	led->led_current = pdata->led_config[chan].led_current;
163	led->max_current = pdata->led_config[chan].max_current;
164	led->chan_nr = pdata->led_config[chan].chan_nr;
165	led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
166
167	if (led->chan_nr >= max_channel) {
168		dev_err(dev, "Use channel numbers between 0 and %d\n",
169			max_channel - 1);
170		return -EINVAL;
171	}
172
173	led->cdev.brightness_set_blocking = lp55xx_set_brightness;
174	led->cdev.groups = lp55xx_led_groups;
175
176	if (pdata->led_config[chan].name) {
177		led->cdev.name = pdata->led_config[chan].name;
178	} else {
179		snprintf(name, sizeof(name), "%s:channel%d",
180			pdata->label ? : chip->cl->name, chan);
181		led->cdev.name = name;
182	}
183
184	ret = led_classdev_register(dev, &led->cdev);
185	if (ret) {
186		dev_err(dev, "led register err: %d\n", ret);
187		return ret;
188	}
189
190	return 0;
191}
192
193static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
194{
195	struct lp55xx_chip *chip = context;
196	struct device *dev = &chip->cl->dev;
197	enum lp55xx_engine_index idx = chip->engine_idx;
198
199	if (!fw) {
200		dev_err(dev, "firmware request failed\n");
201		return;
202	}
203
204	/* handling firmware data is chip dependent */
205	mutex_lock(&chip->lock);
206
207	chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
208	chip->fw = fw;
209	if (chip->cfg->firmware_cb)
210		chip->cfg->firmware_cb(chip);
211
212	mutex_unlock(&chip->lock);
213
214	/* firmware should be released for other channel use */
215	release_firmware(chip->fw);
216	chip->fw = NULL;
217}
218
219static int lp55xx_request_firmware(struct lp55xx_chip *chip)
220{
221	const char *name = chip->cl->name;
222	struct device *dev = &chip->cl->dev;
223
224	return request_firmware_nowait(THIS_MODULE, false, name, dev,
225				GFP_KERNEL, chip, lp55xx_firmware_loaded);
226}
227
228static ssize_t lp55xx_show_engine_select(struct device *dev,
229			    struct device_attribute *attr,
230			    char *buf)
231{
232	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
233	struct lp55xx_chip *chip = led->chip;
234
235	return sprintf(buf, "%d\n", chip->engine_idx);
236}
237
238static ssize_t lp55xx_store_engine_select(struct device *dev,
239			     struct device_attribute *attr,
240			     const char *buf, size_t len)
241{
242	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
243	struct lp55xx_chip *chip = led->chip;
244	unsigned long val;
245	int ret;
246
247	if (kstrtoul(buf, 0, &val))
248		return -EINVAL;
249
250	/* select the engine to be run */
251
252	switch (val) {
253	case LP55XX_ENGINE_1:
254	case LP55XX_ENGINE_2:
255	case LP55XX_ENGINE_3:
256		mutex_lock(&chip->lock);
257		chip->engine_idx = val;
258		ret = lp55xx_request_firmware(chip);
259		mutex_unlock(&chip->lock);
260		break;
261	default:
262		dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
263		return -EINVAL;
264	}
265
266	if (ret) {
267		dev_err(dev, "request firmware err: %d\n", ret);
268		return ret;
269	}
270
271	return len;
272}
273
274static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
275{
276	if (chip->cfg->run_engine)
277		chip->cfg->run_engine(chip, start);
278}
279
280static ssize_t lp55xx_store_engine_run(struct device *dev,
281			     struct device_attribute *attr,
282			     const char *buf, size_t len)
283{
284	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
285	struct lp55xx_chip *chip = led->chip;
286	unsigned long val;
287
288	if (kstrtoul(buf, 0, &val))
289		return -EINVAL;
290
291	/* run or stop the selected engine */
292
293	if (val <= 0) {
294		lp55xx_run_engine(chip, false);
295		return len;
296	}
297
298	mutex_lock(&chip->lock);
299	lp55xx_run_engine(chip, true);
300	mutex_unlock(&chip->lock);
301
302	return len;
303}
304
305static DEVICE_ATTR(select_engine, S_IRUGO | S_IWUSR,
306		   lp55xx_show_engine_select, lp55xx_store_engine_select);
307static DEVICE_ATTR(run_engine, S_IWUSR, NULL, lp55xx_store_engine_run);
308
309static struct attribute *lp55xx_engine_attributes[] = {
310	&dev_attr_select_engine.attr,
311	&dev_attr_run_engine.attr,
312	NULL,
313};
314
315static const struct attribute_group lp55xx_engine_attr_group = {
316	.attrs = lp55xx_engine_attributes,
317};
318
319int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
320{
321	return i2c_smbus_write_byte_data(chip->cl, reg, val);
322}
323EXPORT_SYMBOL_GPL(lp55xx_write);
324
325int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
326{
327	s32 ret;
328
329	ret = i2c_smbus_read_byte_data(chip->cl, reg);
330	if (ret < 0)
331		return ret;
332
333	*val = ret;
334	return 0;
335}
336EXPORT_SYMBOL_GPL(lp55xx_read);
337
338int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
339{
340	int ret;
341	u8 tmp;
342
343	ret = lp55xx_read(chip, reg, &tmp);
344	if (ret)
345		return ret;
346
347	tmp &= ~mask;
348	tmp |= val & mask;
349
350	return lp55xx_write(chip, reg, tmp);
351}
352EXPORT_SYMBOL_GPL(lp55xx_update_bits);
353
354bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
355{
356	struct clk *clk;
357	int err;
358
359	clk = devm_clk_get(&chip->cl->dev, "32k_clk");
360	if (IS_ERR(clk))
361		goto use_internal_clk;
362
363	err = clk_prepare_enable(clk);
364	if (err)
365		goto use_internal_clk;
366
367	if (clk_get_rate(clk) != LP55XX_CLK_32K) {
368		clk_disable_unprepare(clk);
369		goto use_internal_clk;
370	}
371
372	dev_info(&chip->cl->dev, "%dHz external clock used\n",	LP55XX_CLK_32K);
373
374	chip->clk = clk;
375	return true;
376
377use_internal_clk:
378	dev_info(&chip->cl->dev, "internal clock used\n");
379	return false;
380}
381EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);
382
383int lp55xx_init_device(struct lp55xx_chip *chip)
384{
385	struct lp55xx_platform_data *pdata;
386	struct lp55xx_device_config *cfg;
387	struct device *dev = &chip->cl->dev;
388	int ret = 0;
389
390	WARN_ON(!chip);
391
392	pdata = chip->pdata;
393	cfg = chip->cfg;
394
395	if (!pdata || !cfg)
396		return -EINVAL;
397
398	if (gpio_is_valid(pdata->enable_gpio)) {
399		ret = devm_gpio_request_one(dev, pdata->enable_gpio,
400					    GPIOF_DIR_OUT, "lp5523_enable");
401		if (ret < 0) {
402			dev_err(dev, "could not acquire enable gpio (err=%d)\n",
403				ret);
404			goto err;
405		}
406
407		gpio_set_value(pdata->enable_gpio, 0);
 
408		usleep_range(1000, 2000); /* Keep enable down at least 1ms */
409		gpio_set_value(pdata->enable_gpio, 1);
410		usleep_range(1000, 2000); /* 500us abs min. */
411	}
412
413	lp55xx_reset_device(chip);
414
415	/*
416	 * Exact value is not available. 10 - 20ms
417	 * appears to be enough for reset.
418	 */
419	usleep_range(10000, 20000);
420
421	ret = lp55xx_detect_device(chip);
422	if (ret) {
423		dev_err(dev, "device detection err: %d\n", ret);
424		goto err;
425	}
426
427	/* chip specific initialization */
428	ret = lp55xx_post_init_device(chip);
429	if (ret) {
430		dev_err(dev, "post init device err: %d\n", ret);
431		goto err_post_init;
432	}
433
434	return 0;
435
436err_post_init:
437	lp55xx_deinit_device(chip);
438err:
439	return ret;
440}
441EXPORT_SYMBOL_GPL(lp55xx_init_device);
442
443void lp55xx_deinit_device(struct lp55xx_chip *chip)
444{
445	struct lp55xx_platform_data *pdata = chip->pdata;
446
447	if (chip->clk)
448		clk_disable_unprepare(chip->clk);
449
450	if (gpio_is_valid(pdata->enable_gpio))
451		gpio_set_value(pdata->enable_gpio, 0);
452}
453EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
454
455int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
456{
457	struct lp55xx_platform_data *pdata = chip->pdata;
458	struct lp55xx_device_config *cfg = chip->cfg;
459	int num_channels = pdata->num_channels;
460	struct lp55xx_led *each;
461	u8 led_current;
462	int ret;
463	int i;
464
465	if (!cfg->brightness_fn) {
466		dev_err(&chip->cl->dev, "empty brightness configuration\n");
467		return -EINVAL;
468	}
469
470	for (i = 0; i < num_channels; i++) {
471
472		/* do not initialize channels that are not connected */
473		if (pdata->led_config[i].led_current == 0)
474			continue;
475
476		led_current = pdata->led_config[i].led_current;
477		each = led + i;
478		ret = lp55xx_init_led(each, chip, i);
479		if (ret)
480			goto err_init_led;
481
482		chip->num_leds++;
483		each->chip = chip;
484
485		/* setting led current at each channel */
486		if (cfg->set_led_current)
487			cfg->set_led_current(each, led_current);
488	}
489
490	return 0;
491
492err_init_led:
493	lp55xx_unregister_leds(led, chip);
494	return ret;
495}
496EXPORT_SYMBOL_GPL(lp55xx_register_leds);
497
498void lp55xx_unregister_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
499{
500	int i;
501	struct lp55xx_led *each;
502
503	for (i = 0; i < chip->num_leds; i++) {
504		each = led + i;
505		led_classdev_unregister(&each->cdev);
506	}
507}
508EXPORT_SYMBOL_GPL(lp55xx_unregister_leds);
509
510int lp55xx_register_sysfs(struct lp55xx_chip *chip)
511{
512	struct device *dev = &chip->cl->dev;
513	struct lp55xx_device_config *cfg = chip->cfg;
514	int ret;
515
516	if (!cfg->run_engine || !cfg->firmware_cb)
517		goto dev_specific_attrs;
518
519	ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
520	if (ret)
521		return ret;
522
523dev_specific_attrs:
524	return cfg->dev_attr_group ?
525		sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
526}
527EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
528
529void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
530{
531	struct device *dev = &chip->cl->dev;
532	struct lp55xx_device_config *cfg = chip->cfg;
533
534	if (cfg->dev_attr_group)
535		sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);
536
537	sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
538}
539EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);
540
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
541struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
542						      struct device_node *np)
 
543{
544	struct device_node *child;
545	struct lp55xx_platform_data *pdata;
546	struct lp55xx_led_config *cfg;
547	int num_channels;
548	int i = 0;
 
549
550	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
551	if (!pdata)
552		return ERR_PTR(-ENOMEM);
553
554	num_channels = of_get_child_count(np);
555	if (num_channels == 0) {
556		dev_err(dev, "no LED channels\n");
557		return ERR_PTR(-EINVAL);
558	}
559
560	cfg = devm_kcalloc(dev, num_channels, sizeof(*cfg), GFP_KERNEL);
561	if (!cfg)
562		return ERR_PTR(-ENOMEM);
563
564	pdata->led_config = &cfg[0];
565	pdata->num_channels = num_channels;
 
566
567	for_each_child_of_node(np, child) {
568		cfg[i].chan_nr = i;
569
570		of_property_read_string(child, "chan-name", &cfg[i].name);
571		of_property_read_u8(child, "led-cur", &cfg[i].led_current);
572		of_property_read_u8(child, "max-cur", &cfg[i].max_current);
573		cfg[i].default_trigger =
574			of_get_property(child, "linux,default-trigger", NULL);
575
576		i++;
577	}
578
579	of_property_read_string(np, "label", &pdata->label);
580	of_property_read_u8(np, "clock-mode", &pdata->clock_mode);
581
582	pdata->enable_gpio = of_get_named_gpio(np, "enable-gpio", 0);
 
 
 
583
584	/* LP8501 specific */
585	of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);
586
587	return pdata;
588}
589EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);
590
591MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
592MODULE_DESCRIPTION("LP55xx Common Driver");
593MODULE_LICENSE("GPL");