xref: /openbmc/linux/drivers/leds/leds-lp8860.c (revision b830f94f)
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/of_gpio.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/slab.h>
21 #include <uapi/linux/uleds.h>
22 
23 #define LP8860_DISP_CL1_BRT_MSB		0x00
24 #define LP8860_DISP_CL1_BRT_LSB		0x01
25 #define LP8860_DISP_CL1_CURR_MSB	0x02
26 #define LP8860_DISP_CL1_CURR_LSB	0x03
27 #define LP8860_CL2_BRT_MSB		0x04
28 #define LP8860_CL2_BRT_LSB		0x05
29 #define LP8860_CL2_CURRENT		0x06
30 #define LP8860_CL3_BRT_MSB		0x07
31 #define LP8860_CL3_BRT_LSB		0x08
32 #define LP8860_CL3_CURRENT		0x09
33 #define LP8860_CL4_BRT_MSB		0x0a
34 #define LP8860_CL4_BRT_LSB		0x0b
35 #define LP8860_CL4_CURRENT		0x0c
36 #define LP8860_CONFIG			0x0d
37 #define LP8860_STATUS			0x0e
38 #define LP8860_FAULT			0x0f
39 #define LP8860_LED_FAULT		0x10
40 #define LP8860_FAULT_CLEAR		0x11
41 #define LP8860_ID			0x12
42 #define LP8860_TEMP_MSB			0x13
43 #define LP8860_TEMP_LSB			0x14
44 #define LP8860_DISP_LED_CURR_MSB	0x15
45 #define LP8860_DISP_LED_CURR_LSB	0x16
46 #define LP8860_DISP_LED_PWM_MSB		0x17
47 #define LP8860_DISP_LED_PWM_LSB		0x18
48 #define LP8860_EEPROM_CNTRL		0x19
49 #define LP8860_EEPROM_UNLOCK		0x1a
50 
51 #define LP8860_EEPROM_REG_0		0x60
52 #define LP8860_EEPROM_REG_1		0x61
53 #define LP8860_EEPROM_REG_2		0x62
54 #define LP8860_EEPROM_REG_3		0x63
55 #define LP8860_EEPROM_REG_4		0x64
56 #define LP8860_EEPROM_REG_5		0x65
57 #define LP8860_EEPROM_REG_6		0x66
58 #define LP8860_EEPROM_REG_7		0x67
59 #define LP8860_EEPROM_REG_8		0x68
60 #define LP8860_EEPROM_REG_9		0x69
61 #define LP8860_EEPROM_REG_10		0x6a
62 #define LP8860_EEPROM_REG_11		0x6b
63 #define LP8860_EEPROM_REG_12		0x6c
64 #define LP8860_EEPROM_REG_13		0x6d
65 #define LP8860_EEPROM_REG_14		0x6e
66 #define LP8860_EEPROM_REG_15		0x6f
67 #define LP8860_EEPROM_REG_16		0x70
68 #define LP8860_EEPROM_REG_17		0x71
69 #define LP8860_EEPROM_REG_18		0x72
70 #define LP8860_EEPROM_REG_19		0x73
71 #define LP8860_EEPROM_REG_20		0x74
72 #define LP8860_EEPROM_REG_21		0x75
73 #define LP8860_EEPROM_REG_22		0x76
74 #define LP8860_EEPROM_REG_23		0x77
75 #define LP8860_EEPROM_REG_24		0x78
76 
77 #define LP8860_LOCK_EEPROM		0x00
78 #define LP8860_UNLOCK_EEPROM		0x01
79 #define LP8860_PROGRAM_EEPROM		0x02
80 #define LP8860_EEPROM_CODE_1		0x08
81 #define LP8860_EEPROM_CODE_2		0xba
82 #define LP8860_EEPROM_CODE_3		0xef
83 
84 #define LP8860_CLEAR_FAULTS		0x01
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  * @label - LED label
96  */
97 struct lp8860_led {
98 	struct mutex lock;
99 	struct i2c_client *client;
100 	struct led_classdev led_dev;
101 	struct regmap *regmap;
102 	struct regmap *eeprom_regmap;
103 	struct gpio_desc *enable_gpio;
104 	struct regulator *regulator;
105 	char label[LED_MAX_NAME_SIZE];
106 };
107 
108 struct lp8860_eeprom_reg {
109 	uint8_t reg;
110 	uint8_t value;
111 };
112 
113 static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
114 	{ LP8860_EEPROM_REG_0, 0xed },
115 	{ LP8860_EEPROM_REG_1, 0xdf },
116 	{ LP8860_EEPROM_REG_2, 0xdc },
117 	{ LP8860_EEPROM_REG_3, 0xf0 },
118 	{ LP8860_EEPROM_REG_4, 0xdf },
119 	{ LP8860_EEPROM_REG_5, 0xe5 },
120 	{ LP8860_EEPROM_REG_6, 0xf2 },
121 	{ LP8860_EEPROM_REG_7, 0x77 },
122 	{ LP8860_EEPROM_REG_8, 0x77 },
123 	{ LP8860_EEPROM_REG_9, 0x71 },
124 	{ LP8860_EEPROM_REG_10, 0x3f },
125 	{ LP8860_EEPROM_REG_11, 0xb7 },
126 	{ LP8860_EEPROM_REG_12, 0x17 },
127 	{ LP8860_EEPROM_REG_13, 0xef },
128 	{ LP8860_EEPROM_REG_14, 0xb0 },
129 	{ LP8860_EEPROM_REG_15, 0x87 },
130 	{ LP8860_EEPROM_REG_16, 0xce },
131 	{ LP8860_EEPROM_REG_17, 0x72 },
132 	{ LP8860_EEPROM_REG_18, 0xe5 },
133 	{ LP8860_EEPROM_REG_19, 0xdf },
134 	{ LP8860_EEPROM_REG_20, 0x35 },
135 	{ LP8860_EEPROM_REG_21, 0x06 },
136 	{ LP8860_EEPROM_REG_22, 0xdc },
137 	{ LP8860_EEPROM_REG_23, 0x88 },
138 	{ LP8860_EEPROM_REG_24, 0x3E },
139 };
140 
141 static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
142 {
143 	int ret;
144 
145 	mutex_lock(&led->lock);
146 
147 	if (lock == LP8860_UNLOCK_EEPROM) {
148 		ret = regmap_write(led->regmap,
149 			LP8860_EEPROM_UNLOCK,
150 			LP8860_EEPROM_CODE_1);
151 		if (ret) {
152 			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
153 			goto out;
154 		}
155 
156 		ret = regmap_write(led->regmap,
157 			LP8860_EEPROM_UNLOCK,
158 			LP8860_EEPROM_CODE_2);
159 		if (ret) {
160 			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
161 			goto out;
162 		}
163 		ret = regmap_write(led->regmap,
164 			LP8860_EEPROM_UNLOCK,
165 			LP8860_EEPROM_CODE_3);
166 		if (ret) {
167 			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
168 			goto out;
169 		}
170 	} else {
171 		ret = regmap_write(led->regmap,
172 			LP8860_EEPROM_UNLOCK,
173 			LP8860_LOCK_EEPROM);
174 	}
175 
176 out:
177 	mutex_unlock(&led->lock);
178 	return ret;
179 }
180 
181 static int lp8860_fault_check(struct lp8860_led *led)
182 {
183 	int ret, fault;
184 	unsigned int read_buf;
185 
186 	ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
187 	if (ret)
188 		goto out;
189 
190 	fault = read_buf;
191 
192 	ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
193 	if (ret)
194 		goto out;
195 
196 	fault |= read_buf;
197 
198 	/* Attempt to clear any faults */
199 	if (fault)
200 		ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
201 			LP8860_CLEAR_FAULTS);
202 out:
203 	return ret;
204 }
205 
206 static int lp8860_brightness_set(struct led_classdev *led_cdev,
207 				enum led_brightness brt_val)
208 {
209 	struct lp8860_led *led =
210 			container_of(led_cdev, struct lp8860_led, led_dev);
211 	int disp_brightness = brt_val * 255;
212 	int ret;
213 
214 	mutex_lock(&led->lock);
215 
216 	ret = lp8860_fault_check(led);
217 	if (ret) {
218 		dev_err(&led->client->dev, "Cannot read/clear faults\n");
219 		goto out;
220 	}
221 
222 	ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
223 			(disp_brightness & 0xff00) >> 8);
224 	if (ret) {
225 		dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
226 		goto out;
227 	}
228 
229 	ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
230 			disp_brightness & 0xff);
231 	if (ret) {
232 		dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
233 		goto out;
234 	}
235 out:
236 	mutex_unlock(&led->lock);
237 	return ret;
238 }
239 
240 static int lp8860_init(struct lp8860_led *led)
241 {
242 	unsigned int read_buf;
243 	int ret, i, reg_count;
244 
245 	if (led->regulator) {
246 		ret = regulator_enable(led->regulator);
247 		if (ret) {
248 			dev_err(&led->client->dev,
249 				"Failed to enable regulator\n");
250 			return ret;
251 		}
252 	}
253 
254 	if (led->enable_gpio)
255 		gpiod_direction_output(led->enable_gpio, 1);
256 
257 	ret = lp8860_fault_check(led);
258 	if (ret)
259 		goto out;
260 
261 	ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
262 	if (ret)
263 		goto out;
264 
265 	ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
266 	if (ret) {
267 		dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
268 		goto out;
269 	}
270 
271 	reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
272 	for (i = 0; i < reg_count; i++) {
273 		ret = regmap_write(led->eeprom_regmap,
274 				lp8860_eeprom_disp_regs[i].reg,
275 				lp8860_eeprom_disp_regs[i].value);
276 		if (ret) {
277 			dev_err(&led->client->dev, "Failed writing EEPROM\n");
278 			goto out;
279 		}
280 	}
281 
282 	ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
283 	if (ret)
284 		goto out;
285 
286 	ret = regmap_write(led->regmap,
287 			LP8860_EEPROM_CNTRL,
288 			LP8860_PROGRAM_EEPROM);
289 	if (ret) {
290 		dev_err(&led->client->dev, "Failed programming EEPROM\n");
291 		goto out;
292 	}
293 
294 	return ret;
295 
296 out:
297 	if (ret)
298 		if (led->enable_gpio)
299 			gpiod_direction_output(led->enable_gpio, 0);
300 
301 	if (led->regulator) {
302 		ret = regulator_disable(led->regulator);
303 		if (ret)
304 			dev_err(&led->client->dev,
305 				"Failed to disable regulator\n");
306 	}
307 
308 	return ret;
309 }
310 
311 static const struct reg_default lp8860_reg_defs[] = {
312 	{ LP8860_DISP_CL1_BRT_MSB, 0x00},
313 	{ LP8860_DISP_CL1_BRT_LSB, 0x00},
314 	{ LP8860_DISP_CL1_CURR_MSB, 0x00},
315 	{ LP8860_DISP_CL1_CURR_LSB, 0x00},
316 	{ LP8860_CL2_BRT_MSB, 0x00},
317 	{ LP8860_CL2_BRT_LSB, 0x00},
318 	{ LP8860_CL2_CURRENT, 0x00},
319 	{ LP8860_CL3_BRT_MSB, 0x00},
320 	{ LP8860_CL3_BRT_LSB, 0x00},
321 	{ LP8860_CL3_CURRENT, 0x00},
322 	{ LP8860_CL4_BRT_MSB, 0x00},
323 	{ LP8860_CL4_BRT_LSB, 0x00},
324 	{ LP8860_CL4_CURRENT, 0x00},
325 	{ LP8860_CONFIG, 0x00},
326 	{ LP8860_FAULT_CLEAR, 0x00},
327 	{ LP8860_EEPROM_CNTRL, 0x80},
328 	{ LP8860_EEPROM_UNLOCK, 0x00},
329 };
330 
331 static const struct regmap_config lp8860_regmap_config = {
332 	.reg_bits = 8,
333 	.val_bits = 8,
334 
335 	.max_register = LP8860_EEPROM_UNLOCK,
336 	.reg_defaults = lp8860_reg_defs,
337 	.num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
338 	.cache_type = REGCACHE_NONE,
339 };
340 
341 static const struct reg_default lp8860_eeprom_defs[] = {
342 	{ LP8860_EEPROM_REG_0, 0x00 },
343 	{ LP8860_EEPROM_REG_1, 0x00 },
344 	{ LP8860_EEPROM_REG_2, 0x00 },
345 	{ LP8860_EEPROM_REG_3, 0x00 },
346 	{ LP8860_EEPROM_REG_4, 0x00 },
347 	{ LP8860_EEPROM_REG_5, 0x00 },
348 	{ LP8860_EEPROM_REG_6, 0x00 },
349 	{ LP8860_EEPROM_REG_7, 0x00 },
350 	{ LP8860_EEPROM_REG_8, 0x00 },
351 	{ LP8860_EEPROM_REG_9, 0x00 },
352 	{ LP8860_EEPROM_REG_10, 0x00 },
353 	{ LP8860_EEPROM_REG_11, 0x00 },
354 	{ LP8860_EEPROM_REG_12, 0x00 },
355 	{ LP8860_EEPROM_REG_13, 0x00 },
356 	{ LP8860_EEPROM_REG_14, 0x00 },
357 	{ LP8860_EEPROM_REG_15, 0x00 },
358 	{ LP8860_EEPROM_REG_16, 0x00 },
359 	{ LP8860_EEPROM_REG_17, 0x00 },
360 	{ LP8860_EEPROM_REG_18, 0x00 },
361 	{ LP8860_EEPROM_REG_19, 0x00 },
362 	{ LP8860_EEPROM_REG_20, 0x00 },
363 	{ LP8860_EEPROM_REG_21, 0x00 },
364 	{ LP8860_EEPROM_REG_22, 0x00 },
365 	{ LP8860_EEPROM_REG_23, 0x00 },
366 	{ LP8860_EEPROM_REG_24, 0x00 },
367 };
368 
369 static const struct regmap_config lp8860_eeprom_regmap_config = {
370 	.reg_bits = 8,
371 	.val_bits = 8,
372 
373 	.max_register = LP8860_EEPROM_REG_24,
374 	.reg_defaults = lp8860_eeprom_defs,
375 	.num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
376 	.cache_type = REGCACHE_NONE,
377 };
378 
379 static int lp8860_probe(struct i2c_client *client,
380 			const struct i2c_device_id *id)
381 {
382 	int ret;
383 	struct lp8860_led *led;
384 	struct device_node *np = client->dev.of_node;
385 	struct device_node *child_node;
386 	const char *name;
387 
388 	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
389 	if (!led)
390 		return -ENOMEM;
391 
392 	for_each_available_child_of_node(np, child_node) {
393 		led->led_dev.default_trigger = of_get_property(child_node,
394 						    "linux,default-trigger",
395 						    NULL);
396 
397 		ret = of_property_read_string(child_node, "label", &name);
398 		if (!ret)
399 			snprintf(led->label, sizeof(led->label), "%s:%s",
400 				 id->name, name);
401 		else
402 			snprintf(led->label, sizeof(led->label),
403 				"%s::display_cluster", id->name);
404 	}
405 
406 	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
407 						   "enable", GPIOD_OUT_LOW);
408 	if (IS_ERR(led->enable_gpio)) {
409 		ret = PTR_ERR(led->enable_gpio);
410 		dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
411 		return ret;
412 	}
413 
414 	led->regulator = devm_regulator_get(&client->dev, "vled");
415 	if (IS_ERR(led->regulator))
416 		led->regulator = NULL;
417 
418 	led->client = client;
419 	led->led_dev.name = led->label;
420 	led->led_dev.brightness_set_blocking = lp8860_brightness_set;
421 
422 	mutex_init(&led->lock);
423 
424 	i2c_set_clientdata(client, led);
425 
426 	led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
427 	if (IS_ERR(led->regmap)) {
428 		ret = PTR_ERR(led->regmap);
429 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
430 			ret);
431 		return ret;
432 	}
433 
434 	led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
435 	if (IS_ERR(led->eeprom_regmap)) {
436 		ret = PTR_ERR(led->eeprom_regmap);
437 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
438 			ret);
439 		return ret;
440 	}
441 
442 	ret = lp8860_init(led);
443 	if (ret)
444 		return ret;
445 
446 	ret = devm_led_classdev_register(&client->dev, &led->led_dev);
447 	if (ret) {
448 		dev_err(&client->dev, "led register err: %d\n", ret);
449 		return ret;
450 	}
451 
452 	return 0;
453 }
454 
455 static int lp8860_remove(struct i2c_client *client)
456 {
457 	struct lp8860_led *led = i2c_get_clientdata(client);
458 	int ret;
459 
460 	if (led->enable_gpio)
461 		gpiod_direction_output(led->enable_gpio, 0);
462 
463 	if (led->regulator) {
464 		ret = regulator_disable(led->regulator);
465 		if (ret)
466 			dev_err(&led->client->dev,
467 				"Failed to disable regulator\n");
468 	}
469 
470 	mutex_destroy(&led->lock);
471 
472 	return 0;
473 }
474 
475 static const struct i2c_device_id lp8860_id[] = {
476 	{ "lp8860", 0 },
477 	{ }
478 };
479 MODULE_DEVICE_TABLE(i2c, lp8860_id);
480 
481 static const struct of_device_id of_lp8860_leds_match[] = {
482 	{ .compatible = "ti,lp8860", },
483 	{},
484 };
485 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
486 
487 static struct i2c_driver lp8860_driver = {
488 	.driver = {
489 		.name	= "lp8860",
490 		.of_match_table = of_lp8860_leds_match,
491 	},
492 	.probe		= lp8860_probe,
493 	.remove		= lp8860_remove,
494 	.id_table	= lp8860_id,
495 };
496 module_i2c_driver(lp8860_driver);
497 
498 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
499 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
500 MODULE_LICENSE("GPL v2");
501