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(cdev: 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, reg: 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, reg: addr, val);
61 if (ret)
62 return ret;
63
64 usleep_range(min: 1000, max: 2000);
65
66 ret = lp55xx_read(chip, reg: addr, val: &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, fmt: "%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(s: buf, base: 0, res: &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(lock: &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, fmt: "%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(led_cdev: cdev);
142 struct lp55xx_led *led = mcled_cdev_to_led(mc_cdev: mc_dev);
143 struct lp55xx_device_config *cfg = led->chip->cfg;
144
145 led_mc_calc_color_components(mcled_cdev: &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(buf: name, size: sizeof(name), fmt: "%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 n: pdata->led_config[chan].num_colors,
192 size: 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(parent: dev, mcled_cdev: &led->mc_cdev);
226 else
227 ret = devm_led_classdev_register(parent: dev, led_cdev: &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(lock: &chip->lock);
257
258 /* firmware should be released for other channel use */
259 release_firmware(fw: 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, uevent: false, name, device: dev,
269 GFP_KERNEL, context: chip, cont: 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, fmt: "%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(s: buf, base: 0, res: &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(lock: &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(s: buf, base: 0, res: &val))
333 return -EINVAL;
334
335 /* run or stop the selected engine */
336
337 if (val <= 0) {
338 lp55xx_run_engine(chip, start: false);
339 return len;
340 }
341
342 mutex_lock(&chip->lock);
343 lp55xx_run_engine(chip, start: true);
344 mutex_unlock(lock: &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(client: chip->cl, command: reg, value: 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(client: chip->cl, command: 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(dev: &chip->cl->dev, id: "32k_clk");
403 if (IS_ERR(ptr: 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(desc: pdata->enable_gpiod, value: 0);
443
444 gpiod_set_consumer_name(desc: pdata->enable_gpiod, name: "LP55xx enable");
445 gpiod_set_value_cansleep(desc: pdata->enable_gpiod, value: 0);
446 usleep_range(min: 1000, max: 2000); /* Keep enable down at least 1ms */
447 gpiod_set_value_cansleep(desc: pdata->enable_gpiod, value: 1);
448 usleep_range(min: 1000, max: 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(min: 10000, max: 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(clk: chip->clk);
487
488 if (pdata->enable_gpiod)
489 gpiod_set_value(desc: pdata->enable_gpiod, value: 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(led: each, chip, chan: 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(kobj: &dev->kobj, grp: &lp55xx_engine_attr_group);
545 if (ret)
546 return ret;
547
548dev_specific_attrs:
549 return cfg->dev_attr_group ?
550 sysfs_create_group(kobj: &dev->kobj, grp: 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(kobj: &dev->kobj, grp: cfg->dev_attr_group);
561
562 sysfs_remove_group(kobj: &dev->kobj, grp: &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, propname: "chan-name",
573 out_string: &cfg[led_number].name);
574 of_property_read_u8(np, propname: "led-cur",
575 out_value: &cfg[led_number].led_current);
576 of_property_read_u8(np, propname: "max-cur",
577 out_value: &cfg[led_number].max_current);
578
579 ret = of_property_read_u32(np, propname: "reg", out_value: 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(np: child, cfg, led_number: child_number, chan_nr: &chan_nr);
596 if (ret)
597 return ret;
598
599 ret = of_property_read_u32(np: child, propname: "color", out_value: &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 color_number: num_colors);
619 if (ret) {
620 of_node_put(node: 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(node: np, name: "linux,default-trigger", NULL);
640
641 ret = of_property_read_u32(np, propname: "color", out_value: &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, led_number: child_number, chan_nr: &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, size: sizeof(*pdata), GFP_KERNEL);
669 if (!pdata)
670 return ERR_PTR(error: -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(error: -EINVAL);
676 }
677
678 cfg = devm_kcalloc(dev, n: num_channels, size: sizeof(*cfg), GFP_KERNEL);
679 if (!cfg)
680 return ERR_PTR(error: -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(np: child, cfg, child_number: i);
688 if (ret) {
689 of_node_put(node: child);
690 return ERR_PTR(error: -EINVAL);
691 }
692 i++;
693 }
694
695 if (of_property_read_u32(np, propname: "ti,charge-pump-mode", out_value: &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(error: -EINVAL);
701 }
702
703 of_property_read_string(np, propname: "label", out_string: &pdata->label);
704 of_property_read_u8(np, propname: "clock-mode", out_value: &pdata->clock_mode);
705
706 pdata->enable_gpiod = devm_gpiod_get_optional(dev, con_id: "enable",
707 flags: GPIOD_ASIS);
708 if (IS_ERR(ptr: pdata->enable_gpiod))
709 return ERR_CAST(ptr: pdata->enable_gpiod);
710
711 /* LP8501 specific */
712 of_property_read_u8(np, propname: "pwr-sel", out_value: (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

source code of linux/drivers/leds/leds-lp55xx-common.c