leds-lm3601x.c

  1// SPDX-License-Identifier: GPL-2.0
  2// Flash and torch driver for Texas Instruments LM3601X LED
  3// Flash driver chip family
  4// Copyright (C) 2018 Texas Instruments Incorporated - https://www.ti.com/
  5
  6#include <linux/delay.h>
  7#include <linux/i2c.h>
  8#include <linux/leds.h>
  9#include <linux/led-class-flash.h>
 10#include <linux/module.h>
 11#include <linux/regmap.h>
 12#include <linux/slab.h>
 13
 14#define LM3601X_LED_IR		0x0
 15#define LM3601X_LED_TORCH	0x1
 16
 17/* Registers */
 18#define LM3601X_ENABLE_REG	0x01
 19#define LM3601X_CFG_REG		0x02
 20#define LM3601X_LED_FLASH_REG	0x03
 21#define LM3601X_LED_TORCH_REG	0x04
 22#define LM3601X_FLAGS_REG	0x05
 23#define LM3601X_DEV_ID_REG	0x06
 24
 25#define LM3601X_SW_RESET	BIT(7)
 26
 27/* Enable Mode bits */
 28#define LM3601X_MODE_STANDBY	0x00
 29#define LM3601X_MODE_IR_DRV	BIT(0)
 30#define LM3601X_MODE_TORCH	BIT(1)
 31#define LM3601X_MODE_STROBE	(BIT(0) | BIT(1))
 32#define LM3601X_STRB_EN		BIT(2)
 33#define LM3601X_STRB_EDGE_TRIG	BIT(3)
 34#define LM3601X_IVFM_EN		BIT(4)
 35
 36#define LM36010_BOOST_LIMIT_28	BIT(5)
 37#define LM36010_BOOST_FREQ_4MHZ	BIT(6)
 38#define LM36010_BOOST_MODE_PASS	BIT(7)
 39
 40/* Flag Mask */
 41#define LM3601X_FLASH_TIME_OUT	BIT(0)
 42#define LM3601X_UVLO_FAULT	BIT(1)
 43#define LM3601X_THERM_SHUTDOWN	BIT(2)
 44#define LM3601X_THERM_CURR	BIT(3)
 45#define LM36010_CURR_LIMIT	BIT(4)
 46#define LM3601X_SHORT_FAULT	BIT(5)
 47#define LM3601X_IVFM_TRIP	BIT(6)
 48#define LM36010_OVP_FAULT	BIT(7)
 49
 50#define LM3601X_MAX_TORCH_I_UA	376000
 51#define LM3601X_MIN_TORCH_I_UA	2400
 52#define LM3601X_TORCH_REG_DIV	2965
 53
 54#define LM3601X_MAX_STROBE_I_UA	1500000
 55#define LM3601X_MIN_STROBE_I_UA	11000
 56#define LM3601X_STROBE_REG_DIV	11800
 57
 58#define LM3601X_TIMEOUT_MASK	0x1e
 59#define LM3601X_ENABLE_MASK	(LM3601X_MODE_IR_DRV | LM3601X_MODE_TORCH)
 60
 61#define LM3601X_LOWER_STEP_US	40000
 62#define LM3601X_UPPER_STEP_US	200000
 63#define LM3601X_MIN_TIMEOUT_US	40000
 64#define LM3601X_MAX_TIMEOUT_US	1600000
 65#define LM3601X_TIMEOUT_XOVER_US 400000
 66
 67enum lm3601x_type {
 68	CHIP_LM36010 = 0,
 69	CHIP_LM36011,
 70};
 71
 72/**
 73 * struct lm3601x_led - private lm3601x LED data
 74 * @fled_cdev: flash LED class device pointer
 75 * @client: Pointer to the I2C client
 76 * @regmap: Devices register map
 77 * @lock: Lock for reading/writing the device
 78 * @flash_timeout: the timeout for the flash
 79 * @last_flag: last known flags register value
 80 * @torch_current_max: maximum current for the torch
 81 * @flash_current_max: maximum current for the flash
 82 * @max_flash_timeout: maximum timeout for the flash
 83 * @led_mode: The mode to enable either IR or Torch
 84 */
 85struct lm3601x_led {
 86	struct led_classdev_flash fled_cdev;
 87	struct i2c_client *client;
 88	struct regmap *regmap;
 89	struct mutex lock;
 90
 91	unsigned int flash_timeout;
 92	unsigned int last_flag;
 93
 94	u32 torch_current_max;
 95	u32 flash_current_max;
 96	u32 max_flash_timeout;
 97
 98	u32 led_mode;
 99};
100
101static const struct reg_default lm3601x_regmap_defs[] = {
102	{ LM3601X_ENABLE_REG, 0x20 },
103	{ LM3601X_CFG_REG, 0x15 },
104	{ LM3601X_LED_FLASH_REG, 0x00 },
105	{ LM3601X_LED_TORCH_REG, 0x00 },
106};
107
108static bool lm3601x_volatile_reg(struct device *dev, unsigned int reg)
109{
110	switch (reg) {
111	case LM3601X_FLAGS_REG:
112		return true;
113	default:
114		return false;
115	}
116}
117
118static const struct regmap_config lm3601x_regmap = {
119	.reg_bits = 8,
120	.val_bits = 8,
121
122	.max_register = LM3601X_DEV_ID_REG,
123	.reg_defaults = lm3601x_regmap_defs,
124	.num_reg_defaults = ARRAY_SIZE(lm3601x_regmap_defs),
125	.cache_type = REGCACHE_MAPLE,
126	.volatile_reg = lm3601x_volatile_reg,
127};
128
129static struct lm3601x_led *fled_cdev_to_led(struct led_classdev_flash *fled_cdev)
130{
131	return container_of(fled_cdev, struct lm3601x_led, fled_cdev);
132}
133
134static int lm3601x_read_faults(struct lm3601x_led *led)
135{
136	int flags_val;
137	int ret;
138
139	ret = regmap_read(led->regmap, LM3601X_FLAGS_REG, &flags_val);
140	if (ret < 0)
141		return -EIO;
142
143	led->last_flag = 0;
144
145	if (flags_val & LM36010_OVP_FAULT)
146		led->last_flag |= LED_FAULT_OVER_VOLTAGE;
147
148	if (flags_val & (LM3601X_THERM_SHUTDOWN | LM3601X_THERM_CURR))
149		led->last_flag |= LED_FAULT_OVER_TEMPERATURE;
150
151	if (flags_val & LM3601X_SHORT_FAULT)
152		led->last_flag |= LED_FAULT_SHORT_CIRCUIT;
153
154	if (flags_val & LM36010_CURR_LIMIT)
155		led->last_flag |= LED_FAULT_OVER_CURRENT;
156
157	if (flags_val & LM3601X_UVLO_FAULT)
158		led->last_flag |= LED_FAULT_UNDER_VOLTAGE;
159
160	if (flags_val & LM3601X_IVFM_TRIP)
161		led->last_flag |= LED_FAULT_INPUT_VOLTAGE;
162
163	if (flags_val & LM3601X_THERM_SHUTDOWN)
164		led->last_flag |= LED_FAULT_LED_OVER_TEMPERATURE;
165
166	return led->last_flag;
167}
168
169static int lm3601x_brightness_set(struct led_classdev *cdev,
170					enum led_brightness brightness)
171{
172	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(cdev);
173	struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
174	int ret, led_mode_val;
175
176	mutex_lock(&led->lock);
177
178	ret = lm3601x_read_faults(led);
179	if (ret < 0)
180		goto out;
181
182	if (led->led_mode == LM3601X_LED_TORCH)
183		led_mode_val = LM3601X_MODE_TORCH;
184	else
185		led_mode_val = LM3601X_MODE_IR_DRV;
186
187	if (brightness == LED_OFF) {
188		ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
189					led_mode_val, LED_OFF);
190		goto out;
191	}
192
193	ret = regmap_write(led->regmap, LM3601X_LED_TORCH_REG, brightness - 1);
194	if (ret < 0)
195		goto out;
196
197	ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
198				LM3601X_MODE_TORCH | LM3601X_MODE_IR_DRV,
199				led_mode_val);
200out:
201	mutex_unlock(&led->lock);
202	return ret;
203}
204
205static int lm3601x_strobe_set(struct led_classdev_flash *fled_cdev,
206				bool state)
207{
208	struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
209	int timeout_reg_val;
210	int current_timeout;
211	int ret;
212
213	mutex_lock(&led->lock);
214
215	ret = regmap_read(led->regmap, LM3601X_CFG_REG, &current_timeout);
216	if (ret < 0)
217		goto out;
218
219	if (led->flash_timeout >= LM3601X_TIMEOUT_XOVER_US)
220		timeout_reg_val = led->flash_timeout / LM3601X_UPPER_STEP_US + 0x07;
221	else
222		timeout_reg_val = led->flash_timeout / LM3601X_LOWER_STEP_US - 0x01;
223
224	if (led->flash_timeout != current_timeout)
225		ret = regmap_update_bits(led->regmap, LM3601X_CFG_REG,
226					LM3601X_TIMEOUT_MASK, timeout_reg_val);
227
228	if (state)
229		ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
230					LM3601X_MODE_TORCH | LM3601X_MODE_IR_DRV,
231					LM3601X_MODE_STROBE);
232	else
233		ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
234					LM3601X_MODE_STROBE, LED_OFF);
235
236	ret = lm3601x_read_faults(led);
237out:
238	mutex_unlock(&led->lock);
239	return ret;
240}
241
242static int lm3601x_flash_brightness_set(struct led_classdev_flash *fled_cdev,
243					u32 brightness)
244{
245	struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
246	u8 brightness_val;
247	int ret;
248
249	mutex_lock(&led->lock);
250	ret = lm3601x_read_faults(led);
251	if (ret < 0)
252		goto out;
253
254	if (brightness == LED_OFF) {
255		ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
256					LM3601X_MODE_STROBE, LED_OFF);
257		goto out;
258	}
259
260	brightness_val = brightness / LM3601X_STROBE_REG_DIV;
261
262	ret = regmap_write(led->regmap, LM3601X_LED_FLASH_REG, brightness_val);
263out:
264	mutex_unlock(&led->lock);
265	return ret;
266}
267
268static int lm3601x_flash_timeout_set(struct led_classdev_flash *fled_cdev,
269				u32 timeout)
270{
271	struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
272
273	mutex_lock(&led->lock);
274
275	led->flash_timeout = timeout;
276
277	mutex_unlock(&led->lock);
278
279	return 0;
280}
281
282static int lm3601x_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
283{
284	struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
285	int strobe_state;
286	int ret;
287
288	mutex_lock(&led->lock);
289
290	ret = regmap_read(led->regmap, LM3601X_ENABLE_REG, &strobe_state);
291	if (ret < 0)
292		goto out;
293
294	*state = strobe_state & LM3601X_MODE_STROBE;
295
296out:
297	mutex_unlock(&led->lock);
298	return ret;
299}
300
301static int lm3601x_flash_fault_get(struct led_classdev_flash *fled_cdev,
302				u32 *fault)
303{
304	struct lm3601x_led *led = fled_cdev_to_led(fled_cdev);
305
306	lm3601x_read_faults(led);
307
308	*fault = led->last_flag;
309
310	return 0;
311}
312
313static const struct led_flash_ops flash_ops = {
314	.flash_brightness_set	= lm3601x_flash_brightness_set,
315	.strobe_set		= lm3601x_strobe_set,
316	.strobe_get		= lm3601x_strobe_get,
317	.timeout_set		= lm3601x_flash_timeout_set,
318	.fault_get		= lm3601x_flash_fault_get,
319};
320
321static int lm3601x_register_leds(struct lm3601x_led *led,
322				 struct fwnode_handle *fwnode)
323{
324	struct led_classdev *led_cdev;
325	struct led_flash_setting *setting;
326	struct led_init_data init_data = {};
327
328	led->fled_cdev.ops = &flash_ops;
329
330	setting = &led->fled_cdev.timeout;
331	setting->min = LM3601X_MIN_TIMEOUT_US;
332	setting->max = led->max_flash_timeout;
333	setting->step = LM3601X_LOWER_STEP_US;
334	setting->val = led->max_flash_timeout;
335
336	setting = &led->fled_cdev.brightness;
337	setting->min = LM3601X_MIN_STROBE_I_UA;
338	setting->max = led->flash_current_max;
339	setting->step = LM3601X_TORCH_REG_DIV;
340	setting->val = led->flash_current_max;
341
342	led_cdev = &led->fled_cdev.led_cdev;
343	led_cdev->brightness_set_blocking = lm3601x_brightness_set;
344	led_cdev->max_brightness =
345			DIV_ROUND_UP(led->torch_current_max - LM3601X_MIN_TORCH_I_UA + 1,
346				     LM3601X_TORCH_REG_DIV);
347	led_cdev->flags |= LED_DEV_CAP_FLASH;
348
349	init_data.fwnode = fwnode;
350	init_data.devicename = led->client->name;
351	init_data.default_label = (led->led_mode == LM3601X_LED_TORCH) ?
352					"torch" : "infrared";
353	return devm_led_classdev_flash_register_ext(&led->client->dev,
354						&led->fled_cdev, &init_data);
355}
356
357static int lm3601x_parse_node(struct lm3601x_led *led,
358			      struct fwnode_handle **fwnode)
359{
360	struct fwnode_handle *child = NULL;
361	int ret = -ENODEV;
362
363	child = device_get_next_child_node(&led->client->dev, child);
364	if (!child) {
365		dev_err(&led->client->dev, "No LED Child node\n");
366		return ret;
367	}
368
369	ret = fwnode_property_read_u32(child, "reg", &led->led_mode);
370	if (ret) {
371		dev_err(&led->client->dev, "reg DT property missing\n");
372		goto out_err;
373	}
374
375	if (led->led_mode > LM3601X_LED_TORCH ||
376	    led->led_mode < LM3601X_LED_IR) {
377		dev_warn(&led->client->dev, "Invalid led mode requested\n");
378		ret = -EINVAL;
379		goto out_err;
380	}
381
382	ret = fwnode_property_read_u32(child, "led-max-microamp",
383					&led->torch_current_max);
384	if (ret) {
385		dev_warn(&led->client->dev,
386			"led-max-microamp DT property missing\n");
387		goto out_err;
388	}
389
390	if (led->torch_current_max > LM3601X_MAX_TORCH_I_UA) {
391		dev_warn(&led->client->dev,
392			 "Max torch current set too high (%d vs %d)\n",
393			 led->torch_current_max,
394			 LM3601X_MAX_TORCH_I_UA);
395		led->torch_current_max = LM3601X_MAX_TORCH_I_UA;
396	}
397
398	ret = fwnode_property_read_u32(child, "flash-max-microamp",
399				&led->flash_current_max);
400	if (ret) {
401		dev_warn(&led->client->dev,
402			 "flash-max-microamp DT property missing\n");
403		goto out_err;
404	}
405
406	ret = fwnode_property_read_u32(child, "flash-max-timeout-us",
407				&led->max_flash_timeout);
408	if (ret) {
409		dev_warn(&led->client->dev,
410			 "flash-max-timeout-us DT property missing\n");
411		goto out_err;
412	}
413
414	*fwnode = child;
415
416out_err:
417	fwnode_handle_put(child);
418	return ret;
419}
420
421static int lm3601x_probe(struct i2c_client *client)
422{
423	struct lm3601x_led *led;
424	struct fwnode_handle *fwnode;
425	int ret;
426
427	led = devm_kzalloc(&client->dev, sizeof(*led), GFP_KERNEL);
428	if (!led)
429		return -ENOMEM;
430
431	led->client = client;
432	i2c_set_clientdata(client, led);
433
434	ret = lm3601x_parse_node(led, &fwnode);
435	if (ret)
436		return -ENODEV;
437
438	led->regmap = devm_regmap_init_i2c(client, &lm3601x_regmap);
439	if (IS_ERR(led->regmap)) {
440		ret = PTR_ERR(led->regmap);
441		dev_err(&client->dev,
442			"Failed to allocate register map: %d\n", ret);
443		return ret;
444	}
445
446	ret = regmap_write(led->regmap, LM3601X_DEV_ID_REG, LM3601X_SW_RESET);
447	if (ret)
448		dev_warn(&client->dev, "Failed to reset the LED controller\n");
449
450	mutex_init(&led->lock);
451
452	return lm3601x_register_leds(led, fwnode);
453}
454
455static void lm3601x_remove(struct i2c_client *client)
456{
457	struct lm3601x_led *led = i2c_get_clientdata(client);
458	int ret;
459
460	ret = regmap_update_bits(led->regmap, LM3601X_ENABLE_REG,
461				 LM3601X_ENABLE_MASK, LM3601X_MODE_STANDBY);
462	if (ret)
463		dev_warn(&client->dev,
464			 "Failed to put into standby (%pe)\n", ERR_PTR(ret));
465}
466
467static const struct i2c_device_id lm3601x_id[] = {
468	{ "LM36010", CHIP_LM36010 },
469	{ "LM36011", CHIP_LM36011 },
470	{ }
471};
472MODULE_DEVICE_TABLE(i2c, lm3601x_id);
473
474static const struct of_device_id of_lm3601x_leds_match[] = {
475	{ .compatible = "ti,lm36010", },
476	{ .compatible = "ti,lm36011", },
477	{ }
478};
479MODULE_DEVICE_TABLE(of, of_lm3601x_leds_match);
480
481static struct i2c_driver lm3601x_i2c_driver = {
482	.driver = {
483		.name = "lm3601x",
484		.of_match_table = of_lm3601x_leds_match,
485	},
486	.probe = lm3601x_probe,
487	.remove = lm3601x_remove,
488	.id_table = lm3601x_id,
489};
490module_i2c_driver(lm3601x_i2c_driver);
491
492MODULE_DESCRIPTION("Texas Instruments Flash Lighting driver for LM3601X");
493MODULE_AUTHOR("Dan Murphy <dmurphy@ti.com>");
494MODULE_LICENSE("GPL v2");