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 
22 #define LP8860_DISP_CL1_BRT_MSB		0x00
23 #define LP8860_DISP_CL1_BRT_LSB		0x01
24 #define LP8860_DISP_CL1_CURR_MSB	0x02
25 #define LP8860_DISP_CL1_CURR_LSB	0x03
26 #define LP8860_CL2_BRT_MSB		0x04
27 #define LP8860_CL2_BRT_LSB		0x05
28 #define LP8860_CL2_CURRENT		0x06
29 #define LP8860_CL3_BRT_MSB		0x07
30 #define LP8860_CL3_BRT_LSB		0x08
31 #define LP8860_CL3_CURRENT		0x09
32 #define LP8860_CL4_BRT_MSB		0x0a
33 #define LP8860_CL4_BRT_LSB		0x0b
34 #define LP8860_CL4_CURRENT		0x0c
35 #define LP8860_CONFIG			0x0d
36 #define LP8860_STATUS			0x0e
37 #define LP8860_FAULT			0x0f
38 #define LP8860_LED_FAULT		0x10
39 #define LP8860_FAULT_CLEAR		0x11
40 #define LP8860_ID			0x12
41 #define LP8860_TEMP_MSB			0x13
42 #define LP8860_TEMP_LSB			0x14
43 #define LP8860_DISP_LED_CURR_MSB	0x15
44 #define LP8860_DISP_LED_CURR_LSB	0x16
45 #define LP8860_DISP_LED_PWM_MSB		0x17
46 #define LP8860_DISP_LED_PWM_LSB		0x18
47 #define LP8860_EEPROM_CNTRL		0x19
48 #define LP8860_EEPROM_UNLOCK		0x1a
49 
50 #define LP8860_EEPROM_REG_0		0x60
51 #define LP8860_EEPROM_REG_1		0x61
52 #define LP8860_EEPROM_REG_2		0x62
53 #define LP8860_EEPROM_REG_3		0x63
54 #define LP8860_EEPROM_REG_4		0x64
55 #define LP8860_EEPROM_REG_5		0x65
56 #define LP8860_EEPROM_REG_6		0x66
57 #define LP8860_EEPROM_REG_7		0x67
58 #define LP8860_EEPROM_REG_8		0x68
59 #define LP8860_EEPROM_REG_9		0x69
60 #define LP8860_EEPROM_REG_10		0x6a
61 #define LP8860_EEPROM_REG_11		0x6b
62 #define LP8860_EEPROM_REG_12		0x6c
63 #define LP8860_EEPROM_REG_13		0x6d
64 #define LP8860_EEPROM_REG_14		0x6e
65 #define LP8860_EEPROM_REG_15		0x6f
66 #define LP8860_EEPROM_REG_16		0x70
67 #define LP8860_EEPROM_REG_17		0x71
68 #define LP8860_EEPROM_REG_18		0x72
69 #define LP8860_EEPROM_REG_19		0x73
70 #define LP8860_EEPROM_REG_20		0x74
71 #define LP8860_EEPROM_REG_21		0x75
72 #define LP8860_EEPROM_REG_22		0x76
73 #define LP8860_EEPROM_REG_23		0x77
74 #define LP8860_EEPROM_REG_24		0x78
75 
76 #define LP8860_LOCK_EEPROM		0x00
77 #define LP8860_UNLOCK_EEPROM		0x01
78 #define LP8860_PROGRAM_EEPROM		0x02
79 #define LP8860_EEPROM_CODE_1		0x08
80 #define LP8860_EEPROM_CODE_2		0xba
81 #define LP8860_EEPROM_CODE_3		0xef
82 
83 #define LP8860_CLEAR_FAULTS		0x01
84 
85 #define LP8860_NAME			"lp8860"
86 
87 /**
88  * struct lp8860_led
89  * @lock: Lock for reading/writing the device
90  * @client: Pointer to the I2C client
91  * @led_dev: led class device pointer
92  * @regmap: Devices register map
93  * @eeprom_regmap: EEPROM register map
94  * @enable_gpio: VDDIO/EN gpio to enable communication interface
95  * @regulator: LED supply regulator pointer
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 };
106 
107 struct lp8860_eeprom_reg {
108 	uint8_t reg;
109 	uint8_t value;
110 };
111 
112 static struct lp8860_eeprom_reg lp8860_eeprom_disp_regs[] = {
113 	{ LP8860_EEPROM_REG_0, 0xed },
114 	{ LP8860_EEPROM_REG_1, 0xdf },
115 	{ LP8860_EEPROM_REG_2, 0xdc },
116 	{ LP8860_EEPROM_REG_3, 0xf0 },
117 	{ LP8860_EEPROM_REG_4, 0xdf },
118 	{ LP8860_EEPROM_REG_5, 0xe5 },
119 	{ LP8860_EEPROM_REG_6, 0xf2 },
120 	{ LP8860_EEPROM_REG_7, 0x77 },
121 	{ LP8860_EEPROM_REG_8, 0x77 },
122 	{ LP8860_EEPROM_REG_9, 0x71 },
123 	{ LP8860_EEPROM_REG_10, 0x3f },
124 	{ LP8860_EEPROM_REG_11, 0xb7 },
125 	{ LP8860_EEPROM_REG_12, 0x17 },
126 	{ LP8860_EEPROM_REG_13, 0xef },
127 	{ LP8860_EEPROM_REG_14, 0xb0 },
128 	{ LP8860_EEPROM_REG_15, 0x87 },
129 	{ LP8860_EEPROM_REG_16, 0xce },
130 	{ LP8860_EEPROM_REG_17, 0x72 },
131 	{ LP8860_EEPROM_REG_18, 0xe5 },
132 	{ LP8860_EEPROM_REG_19, 0xdf },
133 	{ LP8860_EEPROM_REG_20, 0x35 },
134 	{ LP8860_EEPROM_REG_21, 0x06 },
135 	{ LP8860_EEPROM_REG_22, 0xdc },
136 	{ LP8860_EEPROM_REG_23, 0x88 },
137 	{ LP8860_EEPROM_REG_24, 0x3E },
138 };
139 
lp8860_unlock_eeprom(struct lp8860_led * led,int lock)140 static int lp8860_unlock_eeprom(struct lp8860_led *led, int lock)
141 {
142 	int ret;
143 
144 	mutex_lock(&led->lock);
145 
146 	if (lock == LP8860_UNLOCK_EEPROM) {
147 		ret = regmap_write(led->regmap,
148 			LP8860_EEPROM_UNLOCK,
149 			LP8860_EEPROM_CODE_1);
150 		if (ret) {
151 			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
152 			goto out;
153 		}
154 
155 		ret = regmap_write(led->regmap,
156 			LP8860_EEPROM_UNLOCK,
157 			LP8860_EEPROM_CODE_2);
158 		if (ret) {
159 			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
160 			goto out;
161 		}
162 		ret = regmap_write(led->regmap,
163 			LP8860_EEPROM_UNLOCK,
164 			LP8860_EEPROM_CODE_3);
165 		if (ret) {
166 			dev_err(&led->client->dev, "EEPROM Unlock failed\n");
167 			goto out;
168 		}
169 	} else {
170 		ret = regmap_write(led->regmap,
171 			LP8860_EEPROM_UNLOCK,
172 			LP8860_LOCK_EEPROM);
173 	}
174 
175 out:
176 	mutex_unlock(&led->lock);
177 	return ret;
178 }
179 
lp8860_fault_check(struct lp8860_led * led)180 static int lp8860_fault_check(struct lp8860_led *led)
181 {
182 	int ret, fault;
183 	unsigned int read_buf;
184 
185 	ret = regmap_read(led->regmap, LP8860_LED_FAULT, &read_buf);
186 	if (ret)
187 		goto out;
188 
189 	fault = read_buf;
190 
191 	ret = regmap_read(led->regmap, LP8860_FAULT, &read_buf);
192 	if (ret)
193 		goto out;
194 
195 	fault |= read_buf;
196 
197 	/* Attempt to clear any faults */
198 	if (fault)
199 		ret = regmap_write(led->regmap, LP8860_FAULT_CLEAR,
200 			LP8860_CLEAR_FAULTS);
201 out:
202 	return ret;
203 }
204 
lp8860_brightness_set(struct led_classdev * led_cdev,enum led_brightness brt_val)205 static int lp8860_brightness_set(struct led_classdev *led_cdev,
206 				enum led_brightness brt_val)
207 {
208 	struct lp8860_led *led =
209 			container_of(led_cdev, struct lp8860_led, led_dev);
210 	int disp_brightness = brt_val * 255;
211 	int ret;
212 
213 	mutex_lock(&led->lock);
214 
215 	ret = lp8860_fault_check(led);
216 	if (ret) {
217 		dev_err(&led->client->dev, "Cannot read/clear faults\n");
218 		goto out;
219 	}
220 
221 	ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_MSB,
222 			(disp_brightness & 0xff00) >> 8);
223 	if (ret) {
224 		dev_err(&led->client->dev, "Cannot write CL1 MSB\n");
225 		goto out;
226 	}
227 
228 	ret = regmap_write(led->regmap, LP8860_DISP_CL1_BRT_LSB,
229 			disp_brightness & 0xff);
230 	if (ret) {
231 		dev_err(&led->client->dev, "Cannot write CL1 LSB\n");
232 		goto out;
233 	}
234 out:
235 	mutex_unlock(&led->lock);
236 	return ret;
237 }
238 
lp8860_init(struct lp8860_led * led)239 static int lp8860_init(struct lp8860_led *led)
240 {
241 	unsigned int read_buf;
242 	int ret, i, reg_count;
243 
244 	if (led->regulator) {
245 		ret = regulator_enable(led->regulator);
246 		if (ret) {
247 			dev_err(&led->client->dev,
248 				"Failed to enable regulator\n");
249 			return ret;
250 		}
251 	}
252 
253 	if (led->enable_gpio)
254 		gpiod_direction_output(led->enable_gpio, 1);
255 
256 	ret = lp8860_fault_check(led);
257 	if (ret)
258 		goto out;
259 
260 	ret = regmap_read(led->regmap, LP8860_STATUS, &read_buf);
261 	if (ret)
262 		goto out;
263 
264 	ret = lp8860_unlock_eeprom(led, LP8860_UNLOCK_EEPROM);
265 	if (ret) {
266 		dev_err(&led->client->dev, "Failed unlocking EEPROM\n");
267 		goto out;
268 	}
269 
270 	reg_count = ARRAY_SIZE(lp8860_eeprom_disp_regs) / sizeof(lp8860_eeprom_disp_regs[0]);
271 	for (i = 0; i < reg_count; i++) {
272 		ret = regmap_write(led->eeprom_regmap,
273 				lp8860_eeprom_disp_regs[i].reg,
274 				lp8860_eeprom_disp_regs[i].value);
275 		if (ret) {
276 			dev_err(&led->client->dev, "Failed writing EEPROM\n");
277 			goto out;
278 		}
279 	}
280 
281 	ret = lp8860_unlock_eeprom(led, LP8860_LOCK_EEPROM);
282 	if (ret)
283 		goto out;
284 
285 	ret = regmap_write(led->regmap,
286 			LP8860_EEPROM_CNTRL,
287 			LP8860_PROGRAM_EEPROM);
288 	if (ret) {
289 		dev_err(&led->client->dev, "Failed programming EEPROM\n");
290 		goto out;
291 	}
292 
293 	return ret;
294 
295 out:
296 	if (ret)
297 		if (led->enable_gpio)
298 			gpiod_direction_output(led->enable_gpio, 0);
299 
300 	if (led->regulator) {
301 		ret = regulator_disable(led->regulator);
302 		if (ret)
303 			dev_err(&led->client->dev,
304 				"Failed to disable regulator\n");
305 	}
306 
307 	return ret;
308 }
309 
310 static const struct reg_default lp8860_reg_defs[] = {
311 	{ LP8860_DISP_CL1_BRT_MSB, 0x00},
312 	{ LP8860_DISP_CL1_BRT_LSB, 0x00},
313 	{ LP8860_DISP_CL1_CURR_MSB, 0x00},
314 	{ LP8860_DISP_CL1_CURR_LSB, 0x00},
315 	{ LP8860_CL2_BRT_MSB, 0x00},
316 	{ LP8860_CL2_BRT_LSB, 0x00},
317 	{ LP8860_CL2_CURRENT, 0x00},
318 	{ LP8860_CL3_BRT_MSB, 0x00},
319 	{ LP8860_CL3_BRT_LSB, 0x00},
320 	{ LP8860_CL3_CURRENT, 0x00},
321 	{ LP8860_CL4_BRT_MSB, 0x00},
322 	{ LP8860_CL4_BRT_LSB, 0x00},
323 	{ LP8860_CL4_CURRENT, 0x00},
324 	{ LP8860_CONFIG, 0x00},
325 	{ LP8860_FAULT_CLEAR, 0x00},
326 	{ LP8860_EEPROM_CNTRL, 0x80},
327 	{ LP8860_EEPROM_UNLOCK, 0x00},
328 };
329 
330 static const struct regmap_config lp8860_regmap_config = {
331 	.reg_bits = 8,
332 	.val_bits = 8,
333 
334 	.max_register = LP8860_EEPROM_UNLOCK,
335 	.reg_defaults = lp8860_reg_defs,
336 	.num_reg_defaults = ARRAY_SIZE(lp8860_reg_defs),
337 	.cache_type = REGCACHE_NONE,
338 };
339 
340 static const struct reg_default lp8860_eeprom_defs[] = {
341 	{ LP8860_EEPROM_REG_0, 0x00 },
342 	{ LP8860_EEPROM_REG_1, 0x00 },
343 	{ LP8860_EEPROM_REG_2, 0x00 },
344 	{ LP8860_EEPROM_REG_3, 0x00 },
345 	{ LP8860_EEPROM_REG_4, 0x00 },
346 	{ LP8860_EEPROM_REG_5, 0x00 },
347 	{ LP8860_EEPROM_REG_6, 0x00 },
348 	{ LP8860_EEPROM_REG_7, 0x00 },
349 	{ LP8860_EEPROM_REG_8, 0x00 },
350 	{ LP8860_EEPROM_REG_9, 0x00 },
351 	{ LP8860_EEPROM_REG_10, 0x00 },
352 	{ LP8860_EEPROM_REG_11, 0x00 },
353 	{ LP8860_EEPROM_REG_12, 0x00 },
354 	{ LP8860_EEPROM_REG_13, 0x00 },
355 	{ LP8860_EEPROM_REG_14, 0x00 },
356 	{ LP8860_EEPROM_REG_15, 0x00 },
357 	{ LP8860_EEPROM_REG_16, 0x00 },
358 	{ LP8860_EEPROM_REG_17, 0x00 },
359 	{ LP8860_EEPROM_REG_18, 0x00 },
360 	{ LP8860_EEPROM_REG_19, 0x00 },
361 	{ LP8860_EEPROM_REG_20, 0x00 },
362 	{ LP8860_EEPROM_REG_21, 0x00 },
363 	{ LP8860_EEPROM_REG_22, 0x00 },
364 	{ LP8860_EEPROM_REG_23, 0x00 },
365 	{ LP8860_EEPROM_REG_24, 0x00 },
366 };
367 
368 static const struct regmap_config lp8860_eeprom_regmap_config = {
369 	.reg_bits = 8,
370 	.val_bits = 8,
371 
372 	.max_register = LP8860_EEPROM_REG_24,
373 	.reg_defaults = lp8860_eeprom_defs,
374 	.num_reg_defaults = ARRAY_SIZE(lp8860_eeprom_defs),
375 	.cache_type = REGCACHE_NONE,
376 };
377 
lp8860_probe(struct i2c_client * client)378 static int lp8860_probe(struct i2c_client *client)
379 {
380 	int ret;
381 	struct lp8860_led *led;
382 	struct device_node *np = dev_of_node(&client->dev);
383 	struct device_node *child_node;
384 	struct led_init_data init_data = {};
385 
386 	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
387 	if (!led)
388 		return -ENOMEM;
389 
390 	child_node = of_get_next_available_child(np, NULL);
391 	if (!child_node)
392 		return -EINVAL;
393 
394 	led->enable_gpio = devm_gpiod_get_optional(&client->dev,
395 						   "enable", GPIOD_OUT_LOW);
396 	if (IS_ERR(led->enable_gpio)) {
397 		ret = PTR_ERR(led->enable_gpio);
398 		dev_err(&client->dev, "Failed to get enable gpio: %d\n", ret);
399 		return ret;
400 	}
401 
402 	led->regulator = devm_regulator_get(&client->dev, "vled");
403 	if (IS_ERR(led->regulator))
404 		led->regulator = NULL;
405 
406 	led->client = client;
407 	led->led_dev.brightness_set_blocking = lp8860_brightness_set;
408 
409 	mutex_init(&led->lock);
410 
411 	i2c_set_clientdata(client, led);
412 
413 	led->regmap = devm_regmap_init_i2c(client, &lp8860_regmap_config);
414 	if (IS_ERR(led->regmap)) {
415 		ret = PTR_ERR(led->regmap);
416 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
417 			ret);
418 		return ret;
419 	}
420 
421 	led->eeprom_regmap = devm_regmap_init_i2c(client, &lp8860_eeprom_regmap_config);
422 	if (IS_ERR(led->eeprom_regmap)) {
423 		ret = PTR_ERR(led->eeprom_regmap);
424 		dev_err(&client->dev, "Failed to allocate register map: %d\n",
425 			ret);
426 		return ret;
427 	}
428 
429 	ret = lp8860_init(led);
430 	if (ret)
431 		return ret;
432 
433 	init_data.fwnode = of_fwnode_handle(child_node);
434 	init_data.devicename = LP8860_NAME;
435 	init_data.default_label = ":display_cluster";
436 
437 	ret = devm_led_classdev_register_ext(&client->dev, &led->led_dev,
438 					     &init_data);
439 	if (ret) {
440 		dev_err(&client->dev, "led register err: %d\n", ret);
441 		return ret;
442 	}
443 
444 	return 0;
445 }
446 
lp8860_remove(struct i2c_client * client)447 static void lp8860_remove(struct i2c_client *client)
448 {
449 	struct lp8860_led *led = i2c_get_clientdata(client);
450 	int ret;
451 
452 	if (led->enable_gpio)
453 		gpiod_direction_output(led->enable_gpio, 0);
454 
455 	if (led->regulator) {
456 		ret = regulator_disable(led->regulator);
457 		if (ret)
458 			dev_err(&led->client->dev,
459 				"Failed to disable regulator\n");
460 	}
461 
462 	mutex_destroy(&led->lock);
463 }
464 
465 static const struct i2c_device_id lp8860_id[] = {
466 	{ "lp8860", 0 },
467 	{ }
468 };
469 MODULE_DEVICE_TABLE(i2c, lp8860_id);
470 
471 static const struct of_device_id of_lp8860_leds_match[] = {
472 	{ .compatible = "ti,lp8860", },
473 	{},
474 };
475 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
476 
477 static struct i2c_driver lp8860_driver = {
478 	.driver = {
479 		.name	= "lp8860",
480 		.of_match_table = of_lp8860_leds_match,
481 	},
482 	.probe_new	= lp8860_probe,
483 	.remove		= lp8860_remove,
484 	.id_table	= lp8860_id,
485 };
486 module_i2c_driver(lp8860_driver);
487 
488 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
489 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
490 MODULE_LICENSE("GPL v2");
491