1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * TI LP8860 4-Channel LED Driver
4 *
5 * Copyright (C) 2014 Texas Instruments
6 *
7 * Author: Dan Murphy <dmurphy@ti.com>
8 */
9
10#include <linux/i2c.h>
11#include <linux/init.h>
12#include <linux/leds.h>
13#include <linux/regmap.h>
14#include <linux/regulator/consumer.h>
15#include <linux/module.h>
16#include <linux/mutex.h>
17#include <linux/of.h>
18#include <linux/gpio/consumer.h>
19#include <linux/slab.h>
20
21#define LP8860_DISP_CL1_BRT_MSB		0x00
22#define LP8860_DISP_CL1_BRT_LSB		0x01
23#define LP8860_DISP_CL1_CURR_MSB	0x02
24#define LP8860_DISP_CL1_CURR_LSB	0x03
25#define LP8860_CL2_BRT_MSB		0x04
26#define LP8860_CL2_BRT_LSB		0x05
27#define LP8860_CL2_CURRENT		0x06
28#define LP8860_CL3_BRT_MSB		0x07
29#define LP8860_CL3_BRT_LSB		0x08
30#define LP8860_CL3_CURRENT		0x09
31#define LP8860_CL4_BRT_MSB		0x0a
32#define LP8860_CL4_BRT_LSB		0x0b
33#define LP8860_CL4_CURRENT		0x0c
34#define LP8860_CONFIG			0x0d
35#define LP8860_STATUS			0x0e
36#define LP8860_FAULT			0x0f
37#define LP8860_LED_FAULT		0x10
38#define LP8860_FAULT_CLEAR		0x11
39#define LP8860_ID			0x12
40#define LP8860_TEMP_MSB			0x13
41#define LP8860_TEMP_LSB			0x14
42#define LP8860_DISP_LED_CURR_MSB	0x15
43#define LP8860_DISP_LED_CURR_LSB	0x16
44#define LP8860_DISP_LED_PWM_MSB		0x17
45#define LP8860_DISP_LED_PWM_LSB		0x18
46#define LP8860_EEPROM_CNTRL		0x19
47#define LP8860_EEPROM_UNLOCK		0x1a
48
49#define LP8860_EEPROM_REG_0		0x60
50#define LP8860_EEPROM_REG_1		0x61
51#define LP8860_EEPROM_REG_2		0x62
52#define LP8860_EEPROM_REG_3		0x63
53#define LP8860_EEPROM_REG_4		0x64
54#define LP8860_EEPROM_REG_5		0x65
55#define LP8860_EEPROM_REG_6		0x66
56#define LP8860_EEPROM_REG_7		0x67
57#define LP8860_EEPROM_REG_8		0x68
58#define LP8860_EEPROM_REG_9		0x69
59#define LP8860_EEPROM_REG_10		0x6a
60#define LP8860_EEPROM_REG_11		0x6b
61#define LP8860_EEPROM_REG_12		0x6c
62#define LP8860_EEPROM_REG_13		0x6d
63#define LP8860_EEPROM_REG_14		0x6e
64#define LP8860_EEPROM_REG_15		0x6f
65#define LP8860_EEPROM_REG_16		0x70
66#define LP8860_EEPROM_REG_17		0x71
67#define LP8860_EEPROM_REG_18		0x72
68#define LP8860_EEPROM_REG_19		0x73
69#define LP8860_EEPROM_REG_20		0x74
70#define LP8860_EEPROM_REG_21		0x75
71#define LP8860_EEPROM_REG_22		0x76
72#define LP8860_EEPROM_REG_23		0x77
73#define LP8860_EEPROM_REG_24		0x78
74
75#define LP8860_LOCK_EEPROM		0x00
76#define LP8860_UNLOCK_EEPROM		0x01
77#define LP8860_PROGRAM_EEPROM		0x02
78#define LP8860_EEPROM_CODE_1		0x08
79#define LP8860_EEPROM_CODE_2		0xba
80#define LP8860_EEPROM_CODE_3		0xef
81
82#define LP8860_CLEAR_FAULTS		0x01
83
84#define LP8860_NAME			"lp8860"
85
86/**
87 * struct lp8860_led
88 * @lock: Lock for reading/writing the device
89 * @client: Pointer to the I2C client
90 * @led_dev: led class device pointer
91 * @regmap: Devices register map
92 * @eeprom_regmap: EEPROM register map
93 * @enable_gpio: VDDIO/EN gpio to enable communication interface
94 * @regulator: LED supply regulator pointer
95 */
96struct lp8860_led {
97	struct mutex lock;
98	struct i2c_client *client;
99	struct led_classdev led_dev;
100	struct regmap *regmap;
101	struct regmap *eeprom_regmap;
102	struct gpio_desc *enable_gpio;
103	struct regulator *regulator;
104};
105
106struct lp8860_eeprom_reg {
107	uint8_t reg;
108	uint8_t value;
109};
110
111static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
112	{ LP8860_EEPROM_REG_0, 0xed },
113	{ LP8860_EEPROM_REG_1, 0xdf },
114	{ LP8860_EEPROM_REG_2, 0xdc },
115	{ LP8860_EEPROM_REG_3, 0xf0 },
116	{ LP8860_EEPROM_REG_4, 0xdf },
117	{ LP8860_EEPROM_REG_5, 0xe5 },
118	{ LP8860_EEPROM_REG_6, 0xf2 },
119	{ LP8860_EEPROM_REG_7, 0x77 },
120	{ LP8860_EEPROM_REG_8, 0x77 },
121	{ LP8860_EEPROM_REG_9, 0x71 },
122	{ LP8860_EEPROM_REG_10, 0x3f },
123	{ LP8860_EEPROM_REG_11, 0xb7 },
124	{ LP8860_EEPROM_REG_12, 0x17 },
125	{ LP8860_EEPROM_REG_13, 0xef },
126	{ LP8860_EEPROM_REG_14, 0xb0 },
127	{ LP8860_EEPROM_REG_15, 0x87 },
128	{ LP8860_EEPROM_REG_16, 0xce },
129	{ LP8860_EEPROM_REG_17, 0x72 },
130	{ LP8860_EEPROM_REG_18, 0xe5 },
131	{ LP8860_EEPROM_REG_19, 0xdf },
132	{ LP8860_EEPROM_REG_20, 0x35 },
133	{ LP8860_EEPROM_REG_21, 0x06 },
134	{ LP8860_EEPROM_REG_22, 0xdc },
135	{ LP8860_EEPROM_REG_23, 0x88 },
136	{ LP8860_EEPROM_REG_24, 0x3E },
137};
138
139static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
140{
141	int ret;
142
143	mutex_lock(&led->lock);
144
145	if (lock == LP8860_UNLOCK_EEPROM) {
146		ret = regmap_write(led->regmap,
147			LP8860_EEPROM_UNLOCK,
148			LP8860_EEPROM_CODE_1);
149		if (ret) {
150			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
151			goto out;
152		}
153
154		ret = regmap_write(led->regmap,
155			LP8860_EEPROM_UNLOCK,
156			LP8860_EEPROM_CODE_2);
157		if (ret) {
158			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
159			goto out;
160		}
161		ret = regmap_write(led->regmap,
162			LP8860_EEPROM_UNLOCK,
163			LP8860_EEPROM_CODE_3);
164		if (ret) {
165			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
166			goto out;
167		}
168	} else {
169		ret = regmap_write(led->regmap,
170			LP8860_EEPROM_UNLOCK,
171			LP8860_LOCK_EEPROM);
172	}
173
174out:
175	mutex_unlock(&led->lock);
176	return ret;
177}
178
179static int lp8860_fault_check(struct lp8860_led *led)
180{
181	int ret, fault;
182	unsigned int read_buf;
183
184	ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
185	if (ret)
186		goto out;
187
188	fault = read_buf;
189
190	ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
191	if (ret)
192		goto out;
193
194	fault |= read_buf;
195
196	/* Attempt to clear any faults */
197	if (fault)
198		ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
199			LP8860_CLEAR_FAULTS);
200out:
201	return ret;
202}
203
204static int lp8860_brightness_set(struct led_classdev *led_cdev,
205				enum led_brightness brt_val)
206{
207	struct lp8860_led *led =
208			container_of(led_cdev, struct lp8860_led, led_dev);
209	int disp_brightness = brt_val * 255;
210	int ret;
211
212	mutex_lock(&led->lock);
213
214	ret = lp8860_fault_check(led);
215	if (ret) {
216		dev_err(&led->client->dev, "Cannot read/clear faults\n");
217		goto out;
218	}
219
220	ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
221			(disp_brightness & 0xff00) >> 8);
222	if (ret) {
223		dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
224		goto out;
225	}
226
227	ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
228			disp_brightness & 0xff);
229	if (ret) {
230		dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
231		goto out;
232	}
233out:
234	mutex_unlock(&led->lock);
235	return ret;
236}
237
238static int lp8860_init(struct lp8860_led *led)
239{
240	unsigned int read_buf;
241	int ret, i, reg_count;
242
243	if (led->regulator) {
244		ret = regulator_enable(led->regulator);
245		if (ret) {
246			dev_err(&led->client->dev,
247				"Failed to enable regulator\n");
248			return ret;
249		}
250	}
251
252	gpiod_direction_output(led->enable_gpio, 1);
253
254	ret = lp8860_fault_check(led);
255	if (ret)
256		goto out;
257
258	ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
259	if (ret)
260		goto out;
261
262	ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
263	if (ret) {
264		dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
265		goto out;
266	}
267
268	reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
269	for (i = 0; i < reg_count; i++) {
270		ret = regmap_write(led->eeprom_regmap,
271				lp8860_eeprom_disp_regs[i].reg,
272				lp8860_eeprom_disp_regs[i].value);
273		if (ret) {
274			dev_err(&led->client->dev, "Failed writing EEPROM\n");
275			goto out;
276		}
277	}
278
279	ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
280	if (ret)
281		goto out;
282
283	ret = regmap_write(led->regmap,
284			LP8860_EEPROM_CNTRL,
285			LP8860_PROGRAM_EEPROM);
286	if (ret) {
287		dev_err(&led->client->dev, "Failed programming EEPROM\n");
288		goto out;
289	}
290
291	return ret;
292
293out:
294	if (ret)
295		gpiod_direction_output(led->enable_gpio, 0);
296
297	if (led->regulator) {
298		ret = regulator_disable(led->regulator);
299		if (ret)
300			dev_err(&led->client->dev,
301				"Failed to disable regulator\n");
302	}
303
304	return ret;
305}
306
307static const struct reg_default lp8860_reg_defs[] = {
308	{ LP8860_DISP_CL1_BRT_MSB, 0x00},
309	{ LP8860_DISP_CL1_BRT_LSB, 0x00},
310	{ LP8860_DISP_CL1_CURR_MSB, 0x00},
311	{ LP8860_DISP_CL1_CURR_LSB, 0x00},
312	{ LP8860_CL2_BRT_MSB, 0x00},
313	{ LP8860_CL2_BRT_LSB, 0x00},
314	{ LP8860_CL2_CURRENT, 0x00},
315	{ LP8860_CL3_BRT_MSB, 0x00},
316	{ LP8860_CL3_BRT_LSB, 0x00},
317	{ LP8860_CL3_CURRENT, 0x00},
318	{ LP8860_CL4_BRT_MSB, 0x00},
319	{ LP8860_CL4_BRT_LSB, 0x00},
320	{ LP8860_CL4_CURRENT, 0x00},
321	{ LP8860_CONFIG, 0x00},
322	{ LP8860_FAULT_CLEAR, 0x00},
323	{ LP8860_EEPROM_CNTRL, 0x80},
324	{ LP8860_EEPROM_UNLOCK, 0x00},
325};
326
327static const struct regmap_config lp8860_regmap_config = {
328	.reg_bits = 8,
329	.val_bits = 8,
330
331	.max_register = LP8860_EEPROM_UNLOCK,
332	.reg_defaults = lp8860_reg_defs,
333	.num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
334	.cache_type = REGCACHE_NONE,
335};
336
337static const struct reg_default lp8860_eeprom_defs[] = {
338	{ LP8860_EEPROM_REG_0, 0x00 },
339	{ LP8860_EEPROM_REG_1, 0x00 },
340	{ LP8860_EEPROM_REG_2, 0x00 },
341	{ LP8860_EEPROM_REG_3, 0x00 },
342	{ LP8860_EEPROM_REG_4, 0x00 },
343	{ LP8860_EEPROM_REG_5, 0x00 },
344	{ LP8860_EEPROM_REG_6, 0x00 },
345	{ LP8860_EEPROM_REG_7, 0x00 },
346	{ LP8860_EEPROM_REG_8, 0x00 },
347	{ LP8860_EEPROM_REG_9, 0x00 },
348	{ LP8860_EEPROM_REG_10, 0x00 },
349	{ LP8860_EEPROM_REG_11, 0x00 },
350	{ LP8860_EEPROM_REG_12, 0x00 },
351	{ LP8860_EEPROM_REG_13, 0x00 },
352	{ LP8860_EEPROM_REG_14, 0x00 },
353	{ LP8860_EEPROM_REG_15, 0x00 },
354	{ LP8860_EEPROM_REG_16, 0x00 },
355	{ LP8860_EEPROM_REG_17, 0x00 },
356	{ LP8860_EEPROM_REG_18, 0x00 },
357	{ LP8860_EEPROM_REG_19, 0x00 },
358	{ LP8860_EEPROM_REG_20, 0x00 },
359	{ LP8860_EEPROM_REG_21, 0x00 },
360	{ LP8860_EEPROM_REG_22, 0x00 },
361	{ LP8860_EEPROM_REG_23, 0x00 },
362	{ LP8860_EEPROM_REG_24, 0x00 },
363};
364
365static const struct regmap_config lp8860_eeprom_regmap_config = {
366	.reg_bits = 8,
367	.val_bits = 8,
368
369	.max_register = LP8860_EEPROM_REG_24,
370	.reg_defaults = lp8860_eeprom_defs,
371	.num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
372	.cache_type = REGCACHE_NONE,
373};
374
375static int lp8860_probe(struct i2c_client *client)
376{
377	int ret;
378	struct lp8860_led *led;
379	struct device_node *np = dev_of_node(&client->dev);
380	struct device_node *child_node;
381	struct led_init_data init_data = {};
382
383	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
384	if (!led)
385		return -ENOMEM;
386
387	child_node = of_get_next_available_child(np, NULL);
388	if (!child_node)
389		return -EINVAL;
390
391	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
392						   "enable", GPIOD_OUT_LOW);
393	if (IS_ERR(led->enable_gpio)) {
394		ret = PTR_ERR(led->enable_gpio);
395		dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
396		return ret;
397	}
398
399	led->regulator = devm_regulator_get(&client->dev, "vled");
400	if (IS_ERR(led->regulator))
401		led->regulator = NULL;
402
403	led->client = client;
404	led->led_dev.brightness_set_blocking = lp8860_brightness_set;
405
406	mutex_init(&led->lock);
407
408	i2c_set_clientdata(client, led);
409
410	led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
411	if (IS_ERR(led->regmap)) {
412		ret = PTR_ERR(led->regmap);
413		dev_err(&client->dev, "Failed to allocate register map: %d\n",
414			ret);
415		return ret;
416	}
417
418	led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
419	if (IS_ERR(led->eeprom_regmap)) {
420		ret = PTR_ERR(led->eeprom_regmap);
421		dev_err(&client->dev, "Failed to allocate register map: %d\n",
422			ret);
423		return ret;
424	}
425
426	ret = lp8860_init(led);
427	if (ret)
428		return ret;
429
430	init_data.fwnode = of_fwnode_handle(child_node);
431	init_data.devicename = LP8860_NAME;
432	init_data.default_label = ":display_cluster";
433
434	ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev,
435					     &init_data);
436	if (ret) {
437		dev_err(&client->dev, "led register err: %d\n", ret);
438		return ret;
439	}
440
441	return 0;
442}
443
444static void lp8860_remove(struct i2c_client *client)
445{
446	struct lp8860_led *led = i2c_get_clientdata(client);
447	int ret;
448
449	gpiod_direction_output(led->enable_gpio, 0);
450
451	if (led->regulator) {
452		ret = regulator_disable(led->regulator);
453		if (ret)
454			dev_err(&led->client->dev,
455				"Failed to disable regulator\n");
456	}
457
458	mutex_destroy(&led->lock);
459}
460
461static const struct i2c_device_id lp8860_id[] = {
462	{ "lp8860", 0 },
463	{ }
464};
465MODULE_DEVICE_TABLE(i2c, lp8860_id);
466
467static const struct of_device_id of_lp8860_leds_match[] = {
468	{ .compatible = "ti,lp8860", },
469	{},
470};
471MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
472
473static struct i2c_driver lp8860_driver = {
474	.driver = {
475		.name	= "lp8860",
476		.of_match_table = of_lp8860_leds_match,
477	},
478	.probe		= lp8860_probe,
479	.remove		= lp8860_remove,
480	.id_table	= lp8860_id,
481};
482module_i2c_driver(lp8860_driver);
483
484MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
485MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
486MODULE_LICENSE("GPL v2");
487