xref: /openbmc/linux/drivers/leds/leds-lp8860.c (revision 89df62c3)
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  */
96 struct 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 
106 struct lp8860_eeprom_reg {
107 	uint8_t reg;
108 	uint8_t value;
109 };
110 
111 static 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 
139 static 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 
174 out:
175 	mutex_unlock(&led->lock);
176 	return ret;
177 }
178 
179 static 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);
200 out:
201 	return ret;
202 }
203 
204 static 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 	}
233 out:
234 	mutex_unlock(&led->lock);
235 	return ret;
236 }
237 
238 static 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 
293 out:
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 
307 static 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 
327 static 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 
337 static 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 
365 static 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 
375 static 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 
444 static 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 
461 static const struct i2c_device_id lp8860_id[] = {
462 	{ "lp8860", 0 },
463 	{ }
464 };
465 MODULE_DEVICE_TABLE(i2c, lp8860_id);
466 
467 static const struct of_device_id of_lp8860_leds_match[] = {
468 	{ .compatible = "ti,lp8860", },
469 	{},
470 };
471 MODULE_DEVICE_TABLE(of, of_lp8860_leds_match);
472 
473 static struct i2c_driver lp8860_driver = {
474 	.driver = {
475 		.name	= "lp8860",
476 		.of_match_table = of_lp8860_leds_match,
477 	},
478 	.probe_new	= lp8860_probe,
479 	.remove		= lp8860_remove,
480 	.id_table	= lp8860_id,
481 };
482 module_i2c_driver(lp8860_driver);
483 
484 MODULE_DESCRIPTION("Texas Instruments LP8860 LED driver");
485 MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
486 MODULE_LICENSE("GPL v2");
487