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#include <dt-bindings/leds/leds-lp55xx.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 struct lp55xx_led *mcled_cdev_to_led(struct led_classdev_mc *mc_cdev)
39{
40	return container_of(mc_cdev, struct lp55xx_led, mc_cdev);
41}
42
43static void lp55xx_reset_device(struct lp55xx_chip *chip)
44{
45	struct lp55xx_device_config *cfg = chip->cfg;
46	u8 addr = cfg->reset.addr;
47	u8 val  = cfg->reset.val;
48
49	/* no error checking here because no ACK from the device after reset */
50	lp55xx_write(chip, addr, val);
51}
52
53static int lp55xx_detect_device(struct lp55xx_chip *chip)
54{
55	struct lp55xx_device_config *cfg = chip->cfg;
56	u8 addr = cfg->enable.addr;
57	u8 val  = cfg->enable.val;
58	int ret;
59
60	ret = lp55xx_write(chip, addr, val);
61	if (ret)
62		return ret;
63
64	usleep_range(1000, 2000);
65
66	ret = lp55xx_read(chip, addr, &val);
67	if (ret)
68		return ret;
69
70	if (val != cfg->enable.val)
71		return -ENODEV;
72
73	return 0;
74}
75
76static int lp55xx_post_init_device(struct lp55xx_chip *chip)
77{
78	struct lp55xx_device_config *cfg = chip->cfg;
79
80	if (!cfg->post_init_device)
81		return 0;
82
83	return cfg->post_init_device(chip);
84}
85
86static ssize_t led_current_show(struct device *dev,
87			    struct device_attribute *attr,
88			    char *buf)
89{
90	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
91
92	return sysfs_emit(buf, "%d\n", led->led_current);
93}
94
95static ssize_t led_current_store(struct device *dev,
96			     struct device_attribute *attr,
97			     const char *buf, size_t len)
98{
99	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
100	struct lp55xx_chip *chip = led->chip;
101	unsigned long curr;
102
103	if (kstrtoul(buf, 0, &curr))
104		return -EINVAL;
105
106	if (curr > led->max_current)
107		return -EINVAL;
108
109	if (!chip->cfg->set_led_current)
110		return len;
111
112	mutex_lock(&chip->lock);
113	chip->cfg->set_led_current(led, (u8)curr);
114	mutex_unlock(&chip->lock);
115
116	return len;
117}
118
119static ssize_t max_current_show(struct device *dev,
120			    struct device_attribute *attr,
121			    char *buf)
122{
123	struct lp55xx_led *led = dev_to_lp55xx_led(dev);
124
125	return sysfs_emit(buf, "%d\n", led->max_current);
126}
127
128static DEVICE_ATTR_RW(led_current);
129static DEVICE_ATTR_RO(max_current);
130
131static struct attribute *lp55xx_led_attrs[] = {
132	&dev_attr_led_current.attr,
133	&dev_attr_max_current.attr,
134	NULL,
135};
136ATTRIBUTE_GROUPS(lp55xx_led);
137
138static int lp55xx_set_mc_brightness(struct led_classdev *cdev,
139				    enum led_brightness brightness)
140{
141	struct led_classdev_mc *mc_dev = lcdev_to_mccdev(cdev);
142	struct lp55xx_led *led = mcled_cdev_to_led(mc_dev);
143	struct lp55xx_device_config *cfg = led->chip->cfg;
144
145	led_mc_calc_color_components(&led->mc_cdev, brightness);
146	return cfg->multicolor_brightness_fn(led);
147
148}
149
150static int lp55xx_set_brightness(struct led_classdev *cdev,
151			     enum led_brightness brightness)
152{
153	struct lp55xx_led *led = cdev_to_lp55xx_led(cdev);
154	struct lp55xx_device_config *cfg = led->chip->cfg;
155
156	led->brightness = (u8)brightness;
157	return cfg->brightness_fn(led);
158}
159
160static int lp55xx_init_led(struct lp55xx_led *led,
161			struct lp55xx_chip *chip, int chan)
162{
163	struct lp55xx_platform_data *pdata = chip->pdata;
164	struct lp55xx_device_config *cfg = chip->cfg;
165	struct device *dev = &chip->cl->dev;
166	int max_channel = cfg->max_channel;
167	struct mc_subled *mc_led_info;
168	struct led_classdev *led_cdev;
169	char name[32];
170	int i;
171	int ret;
172
173	if (chan >= max_channel) {
174		dev_err(dev, "invalid channel: %d / %d\n", chan, max_channel);
175		return -EINVAL;
176	}
177
178	if (pdata->led_config[chan].led_current == 0)
179		return 0;
180
181	if (pdata->led_config[chan].name) {
182		led->cdev.name = pdata->led_config[chan].name;
183	} else {
184		snprintf(name, sizeof(name), "%s:channel%d",
185			pdata->label ? : chip->cl->name, chan);
186		led->cdev.name = name;
187	}
188
189	if (pdata->led_config[chan].num_colors > 1) {
190		mc_led_info = devm_kcalloc(dev,
191					   pdata->led_config[chan].num_colors,
192					   sizeof(*mc_led_info), GFP_KERNEL);
193		if (!mc_led_info)
194			return -ENOMEM;
195
196		led_cdev = &led->mc_cdev.led_cdev;
197		led_cdev->name = led->cdev.name;
198		led_cdev->brightness_set_blocking = lp55xx_set_mc_brightness;
199		led->mc_cdev.num_colors = pdata->led_config[chan].num_colors;
200		for (i = 0; i < led->mc_cdev.num_colors; i++) {
201			mc_led_info[i].color_index =
202				pdata->led_config[chan].color_id[i];
203			mc_led_info[i].channel =
204					pdata->led_config[chan].output_num[i];
205		}
206
207		led->mc_cdev.subled_info = mc_led_info;
208	} else {
209		led->cdev.brightness_set_blocking = lp55xx_set_brightness;
210	}
211
212	led->cdev.groups = lp55xx_led_groups;
213	led->cdev.default_trigger = pdata->led_config[chan].default_trigger;
214	led->led_current = pdata->led_config[chan].led_current;
215	led->max_current = pdata->led_config[chan].max_current;
216	led->chan_nr = pdata->led_config[chan].chan_nr;
217
218	if (led->chan_nr >= max_channel) {
219		dev_err(dev, "Use channel numbers between 0 and %d\n",
220			max_channel - 1);
221		return -EINVAL;
222	}
223
224	if (pdata->led_config[chan].num_colors > 1)
225		ret = devm_led_classdev_multicolor_register(dev, &led->mc_cdev);
226	else
227		ret = devm_led_classdev_register(dev, &led->cdev);
228
229	if (ret) {
230		dev_err(dev, "led register err: %d\n", ret);
231		return ret;
232	}
233
234	return 0;
235}
236
237static void lp55xx_firmware_loaded(const struct firmware *fw, void *context)
238{
239	struct lp55xx_chip *chip = context;
240	struct device *dev = &chip->cl->dev;
241	enum lp55xx_engine_index idx = chip->engine_idx;
242
243	if (!fw) {
244		dev_err(dev, "firmware request failed\n");
245		return;
246	}
247
248	/* handling firmware data is chip dependent */
249	mutex_lock(&chip->lock);
250
251	chip->engines[idx - 1].mode = LP55XX_ENGINE_LOAD;
252	chip->fw = fw;
253	if (chip->cfg->firmware_cb)
254		chip->cfg->firmware_cb(chip);
255
256	mutex_unlock(&chip->lock);
257
258	/* firmware should be released for other channel use */
259	release_firmware(chip->fw);
260	chip->fw = NULL;
261}
262
263static int lp55xx_request_firmware(struct lp55xx_chip *chip)
264{
265	const char *name = chip->cl->name;
266	struct device *dev = &chip->cl->dev;
267
268	return request_firmware_nowait(THIS_MODULE, false, name, dev,
269				GFP_KERNEL, chip, lp55xx_firmware_loaded);
270}
271
272static ssize_t select_engine_show(struct device *dev,
273			    struct device_attribute *attr,
274			    char *buf)
275{
276	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
277	struct lp55xx_chip *chip = led->chip;
278
279	return sprintf(buf, "%d\n", chip->engine_idx);
280}
281
282static ssize_t select_engine_store(struct device *dev,
283			     struct device_attribute *attr,
284			     const char *buf, size_t len)
285{
286	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
287	struct lp55xx_chip *chip = led->chip;
288	unsigned long val;
289	int ret;
290
291	if (kstrtoul(buf, 0, &val))
292		return -EINVAL;
293
294	/* select the engine to be run */
295
296	switch (val) {
297	case LP55XX_ENGINE_1:
298	case LP55XX_ENGINE_2:
299	case LP55XX_ENGINE_3:
300		mutex_lock(&chip->lock);
301		chip->engine_idx = val;
302		ret = lp55xx_request_firmware(chip);
303		mutex_unlock(&chip->lock);
304		break;
305	default:
306		dev_err(dev, "%lu: invalid engine index. (1, 2, 3)\n", val);
307		return -EINVAL;
308	}
309
310	if (ret) {
311		dev_err(dev, "request firmware err: %d\n", ret);
312		return ret;
313	}
314
315	return len;
316}
317
318static inline void lp55xx_run_engine(struct lp55xx_chip *chip, bool start)
319{
320	if (chip->cfg->run_engine)
321		chip->cfg->run_engine(chip, start);
322}
323
324static ssize_t run_engine_store(struct device *dev,
325			     struct device_attribute *attr,
326			     const char *buf, size_t len)
327{
328	struct lp55xx_led *led = i2c_get_clientdata(to_i2c_client(dev));
329	struct lp55xx_chip *chip = led->chip;
330	unsigned long val;
331
332	if (kstrtoul(buf, 0, &val))
333		return -EINVAL;
334
335	/* run or stop the selected engine */
336
337	if (val <= 0) {
338		lp55xx_run_engine(chip, false);
339		return len;
340	}
341
342	mutex_lock(&chip->lock);
343	lp55xx_run_engine(chip, true);
344	mutex_unlock(&chip->lock);
345
346	return len;
347}
348
349static DEVICE_ATTR_RW(select_engine);
350static DEVICE_ATTR_WO(run_engine);
351
352static struct attribute *lp55xx_engine_attributes[] = {
353	&dev_attr_select_engine.attr,
354	&dev_attr_run_engine.attr,
355	NULL,
356};
357
358static const struct attribute_group lp55xx_engine_attr_group = {
359	.attrs = lp55xx_engine_attributes,
360};
361
362int lp55xx_write(struct lp55xx_chip *chip, u8 reg, u8 val)
363{
364	return i2c_smbus_write_byte_data(chip->cl, reg, val);
365}
366EXPORT_SYMBOL_GPL(lp55xx_write);
367
368int lp55xx_read(struct lp55xx_chip *chip, u8 reg, u8 *val)
369{
370	s32 ret;
371
372	ret = i2c_smbus_read_byte_data(chip->cl, reg);
373	if (ret < 0)
374		return ret;
375
376	*val = ret;
377	return 0;
378}
379EXPORT_SYMBOL_GPL(lp55xx_read);
380
381int lp55xx_update_bits(struct lp55xx_chip *chip, u8 reg, u8 mask, u8 val)
382{
383	int ret;
384	u8 tmp;
385
386	ret = lp55xx_read(chip, reg, &tmp);
387	if (ret)
388		return ret;
389
390	tmp &= ~mask;
391	tmp |= val & mask;
392
393	return lp55xx_write(chip, reg, tmp);
394}
395EXPORT_SYMBOL_GPL(lp55xx_update_bits);
396
397bool lp55xx_is_extclk_used(struct lp55xx_chip *chip)
398{
399	struct clk *clk;
400	int err;
401
402	clk = devm_clk_get(&chip->cl->dev, "32k_clk");
403	if (IS_ERR(clk))
404		goto use_internal_clk;
405
406	err = clk_prepare_enable(clk);
407	if (err)
408		goto use_internal_clk;
409
410	if (clk_get_rate(clk) != LP55XX_CLK_32K) {
411		clk_disable_unprepare(clk);
412		goto use_internal_clk;
413	}
414
415	dev_info(&chip->cl->dev, "%dHz external clock used\n",	LP55XX_CLK_32K);
416
417	chip->clk = clk;
418	return true;
419
420use_internal_clk:
421	dev_info(&chip->cl->dev, "internal clock used\n");
422	return false;
423}
424EXPORT_SYMBOL_GPL(lp55xx_is_extclk_used);
425
426int lp55xx_init_device(struct lp55xx_chip *chip)
427{
428	struct lp55xx_platform_data *pdata;
429	struct lp55xx_device_config *cfg;
430	struct device *dev = &chip->cl->dev;
431	int ret = 0;
432
433	WARN_ON(!chip);
434
435	pdata = chip->pdata;
436	cfg = chip->cfg;
437
438	if (!pdata || !cfg)
439		return -EINVAL;
440
441	if (pdata->enable_gpiod) {
442		gpiod_direction_output(pdata->enable_gpiod, 0);
443
444		gpiod_set_consumer_name(pdata->enable_gpiod, "LP55xx enable");
445		gpiod_set_value_cansleep(pdata->enable_gpiod, 0);
446		usleep_range(1000, 2000); /* Keep enable down at least 1ms */
447		gpiod_set_value_cansleep(pdata->enable_gpiod, 1);
448		usleep_range(1000, 2000); /* 500us abs min. */
449	}
450
451	lp55xx_reset_device(chip);
452
453	/*
454	 * Exact value is not available. 10 - 20ms
455	 * appears to be enough for reset.
456	 */
457	usleep_range(10000, 20000);
458
459	ret = lp55xx_detect_device(chip);
460	if (ret) {
461		dev_err(dev, "device detection err: %d\n", ret);
462		goto err;
463	}
464
465	/* chip specific initialization */
466	ret = lp55xx_post_init_device(chip);
467	if (ret) {
468		dev_err(dev, "post init device err: %d\n", ret);
469		goto err_post_init;
470	}
471
472	return 0;
473
474err_post_init:
475	lp55xx_deinit_device(chip);
476err:
477	return ret;
478}
479EXPORT_SYMBOL_GPL(lp55xx_init_device);
480
481void lp55xx_deinit_device(struct lp55xx_chip *chip)
482{
483	struct lp55xx_platform_data *pdata = chip->pdata;
484
485	if (chip->clk)
486		clk_disable_unprepare(chip->clk);
487
488	if (pdata->enable_gpiod)
489		gpiod_set_value(pdata->enable_gpiod, 0);
490}
491EXPORT_SYMBOL_GPL(lp55xx_deinit_device);
492
493int lp55xx_register_leds(struct lp55xx_led *led, struct lp55xx_chip *chip)
494{
495	struct lp55xx_platform_data *pdata = chip->pdata;
496	struct lp55xx_device_config *cfg = chip->cfg;
497	int num_channels = pdata->num_channels;
498	struct lp55xx_led *each;
499	u8 led_current;
500	int ret;
501	int i;
502
503	if (!cfg->brightness_fn) {
504		dev_err(&chip->cl->dev, "empty brightness configuration\n");
505		return -EINVAL;
506	}
507
508	for (i = 0; i < num_channels; i++) {
509
510		/* do not initialize channels that are not connected */
511		if (pdata->led_config[i].led_current == 0)
512			continue;
513
514		led_current = pdata->led_config[i].led_current;
515		each = led + i;
516		ret = lp55xx_init_led(each, chip, i);
517		if (ret)
518			goto err_init_led;
519
520		chip->num_leds++;
521		each->chip = chip;
522
523		/* setting led current at each channel */
524		if (cfg->set_led_current)
525			cfg->set_led_current(each, led_current);
526	}
527
528	return 0;
529
530err_init_led:
531	return ret;
532}
533EXPORT_SYMBOL_GPL(lp55xx_register_leds);
534
535int lp55xx_register_sysfs(struct lp55xx_chip *chip)
536{
537	struct device *dev = &chip->cl->dev;
538	struct lp55xx_device_config *cfg = chip->cfg;
539	int ret;
540
541	if (!cfg->run_engine || !cfg->firmware_cb)
542		goto dev_specific_attrs;
543
544	ret = sysfs_create_group(&dev->kobj, &lp55xx_engine_attr_group);
545	if (ret)
546		return ret;
547
548dev_specific_attrs:
549	return cfg->dev_attr_group ?
550		sysfs_create_group(&dev->kobj, cfg->dev_attr_group) : 0;
551}
552EXPORT_SYMBOL_GPL(lp55xx_register_sysfs);
553
554void lp55xx_unregister_sysfs(struct lp55xx_chip *chip)
555{
556	struct device *dev = &chip->cl->dev;
557	struct lp55xx_device_config *cfg = chip->cfg;
558
559	if (cfg->dev_attr_group)
560		sysfs_remove_group(&dev->kobj, cfg->dev_attr_group);
561
562	sysfs_remove_group(&dev->kobj, &lp55xx_engine_attr_group);
563}
564EXPORT_SYMBOL_GPL(lp55xx_unregister_sysfs);
565
566static int lp55xx_parse_common_child(struct device_node *np,
567				     struct lp55xx_led_config *cfg,
568				     int led_number, int *chan_nr)
569{
570	int ret;
571
572	of_property_read_string(np, "chan-name",
573				&cfg[led_number].name);
574	of_property_read_u8(np, "led-cur",
575			    &cfg[led_number].led_current);
576	of_property_read_u8(np, "max-cur",
577			    &cfg[led_number].max_current);
578
579	ret = of_property_read_u32(np, "reg", chan_nr);
580	if (ret)
581		return ret;
582
583	if (*chan_nr < 0 || *chan_nr > cfg->max_channel)
584		return -EINVAL;
585
586	return 0;
587}
588
589static int lp55xx_parse_multi_led_child(struct device_node *child,
590					 struct lp55xx_led_config *cfg,
591					 int child_number, int color_number)
592{
593	int chan_nr, color_id, ret;
594
595	ret = lp55xx_parse_common_child(child, cfg, child_number, &chan_nr);
596	if (ret)
597		return ret;
598
599	ret = of_property_read_u32(child, "color", &color_id);
600	if (ret)
601		return ret;
602
603	cfg[child_number].color_id[color_number] = color_id;
604	cfg[child_number].output_num[color_number] = chan_nr;
605
606	return 0;
607}
608
609static int lp55xx_parse_multi_led(struct device_node *np,
610				  struct lp55xx_led_config *cfg,
611				  int child_number)
612{
613	struct device_node *child;
614	int num_colors = 0, ret;
615
616	for_each_available_child_of_node(np, child) {
617		ret = lp55xx_parse_multi_led_child(child, cfg, child_number,
618						   num_colors);
619		if (ret) {
620			of_node_put(child);
621			return ret;
622		}
623		num_colors++;
624	}
625
626	cfg[child_number].num_colors = num_colors;
627
628	return 0;
629}
630
631static int lp55xx_parse_logical_led(struct device_node *np,
632				   struct lp55xx_led_config *cfg,
633				   int child_number)
634{
635	int led_color, ret;
636	int chan_nr = 0;
637
638	cfg[child_number].default_trigger =
639		of_get_property(np, "linux,default-trigger", NULL);
640
641	ret = of_property_read_u32(np, "color", &led_color);
642	if (ret)
643		return ret;
644
645	if (led_color == LED_COLOR_ID_RGB)
646		return lp55xx_parse_multi_led(np, cfg, child_number);
647
648	ret =  lp55xx_parse_common_child(np, cfg, child_number, &chan_nr);
649	if (ret < 0)
650		return ret;
651
652	cfg[child_number].chan_nr = chan_nr;
653
654	return ret;
655}
656
657struct lp55xx_platform_data *lp55xx_of_populate_pdata(struct device *dev,
658						      struct device_node *np,
659						      struct lp55xx_chip *chip)
660{
661	struct device_node *child;
662	struct lp55xx_platform_data *pdata;
663	struct lp55xx_led_config *cfg;
664	int num_channels;
665	int i = 0;
666	int ret;
667
668	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
669	if (!pdata)
670		return ERR_PTR(-ENOMEM);
671
672	num_channels = of_get_available_child_count(np);
673	if (num_channels == 0) {
674		dev_err(dev, "no LED channels\n");
675		return ERR_PTR(-EINVAL);
676	}
677
678	cfg = devm_kcalloc(dev, num_channels, sizeof(*cfg), GFP_KERNEL);
679	if (!cfg)
680		return ERR_PTR(-ENOMEM);
681
682	pdata->led_config = &cfg[0];
683	pdata->num_channels = num_channels;
684	cfg->max_channel = chip->cfg->max_channel;
685
686	for_each_available_child_of_node(np, child) {
687		ret = lp55xx_parse_logical_led(child, cfg, i);
688		if (ret) {
689			of_node_put(child);
690			return ERR_PTR(-EINVAL);
691		}
692		i++;
693	}
694
695	if (of_property_read_u32(np, "ti,charge-pump-mode", &pdata->charge_pump_mode))
696		pdata->charge_pump_mode = LP55XX_CP_AUTO;
697
698	if (pdata->charge_pump_mode > LP55XX_CP_AUTO) {
699		dev_err(dev, "invalid charge pump mode %d\n", pdata->charge_pump_mode);
700		return ERR_PTR(-EINVAL);
701	}
702
703	of_property_read_string(np, "label", &pdata->label);
704	of_property_read_u8(np, "clock-mode", &pdata->clock_mode);
705
706	pdata->enable_gpiod = devm_gpiod_get_optional(dev, "enable",
707						      GPIOD_ASIS);
708	if (IS_ERR(pdata->enable_gpiod))
709		return ERR_CAST(pdata->enable_gpiod);
710
711	/* LP8501 specific */
712	of_property_read_u8(np, "pwr-sel", (u8 *)&pdata->pwr_sel);
713
714	return pdata;
715}
716EXPORT_SYMBOL_GPL(lp55xx_of_populate_pdata);
717
718MODULE_AUTHOR("Milo Kim <milo.kim@ti.com>");
719MODULE_DESCRIPTION("LP55xx Common Driver");
720MODULE_LICENSE("GPL");
721