xref: /linux/drivers/leds/flash/leds-tps6131x.c (revision e9ef810dfee7a2227da9d423aecb0ced35faddbe)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Texas Instruments TPS61310/TPS61311 flash LED driver with I2C interface
4  *
5  * Copyright 2025 Matthias Fend <matthias.fend@emfend.at>
6  */
7 
8 #include <linux/gpio/consumer.h>
9 #include <linux/i2c.h>
10 #include <linux/led-class-flash.h>
11 #include <linux/leds.h>
12 #include <linux/module.h>
13 #include <linux/regmap.h>
14 #include <media/v4l2-flash-led-class.h>
15 
16 #define TPS6131X_REG_0				0x00
17 #define   TPS6131X_REG_0_RESET			BIT(7)
18 #define   TPS6131X_REG_0_DCLC13			GENMASK(5, 3)
19 #define   TPS6131X_REG_0_DCLC13_SHIFT		3
20 #define   TPS6131X_REG_0_DCLC2			GENMASK(2, 0)
21 #define   TPS6131X_REG_0_DCLC2_SHIFT		0
22 
23 #define TPS6131X_REG_1				0x01
24 #define   TPS6131X_REG_1_MODE			GENMASK(7, 6)
25 #define   TPS6131X_REG_1_MODE_SHIFT		6
26 #define   TPS6131X_REG_1_FC2			GENMASK(5, 0)
27 #define   TPS6131X_REG_1_FC2_SHIFT		0
28 
29 #define TPS6131X_REG_2				0x02
30 #define   TPS6131X_REG_2_MODE			GENMASK(7, 6)
31 #define   TPS6131X_REG_2_MODE_SHIFT		6
32 #define   TPS6131X_REG_2_ENVM			BIT(5)
33 #define   TPS6131X_REG_2_FC13			GENMASK(4, 0)
34 #define   TPS6131X_REG_2_FC13_SHIFT		0
35 
36 #define TPS6131X_REG_3				0x03
37 #define   TPS6131X_REG_3_STIM			GENMASK(7, 5)
38 #define   TPS6131X_REG_3_STIM_SHIFT		5
39 #define   TPS6131X_REG_3_HPFL			BIT(4)
40 #define   TPS6131X_REG_3_SELSTIM_TO		BIT(3)
41 #define   TPS6131X_REG_3_STT			BIT(2)
42 #define   TPS6131X_REG_3_SFT			BIT(1)
43 #define   TPS6131X_REG_3_TXMASK			BIT(0)
44 
45 #define TPS6131X_REG_4				0x04
46 #define   TPS6131X_REG_4_PG			BIT(7)
47 #define   TPS6131X_REG_4_HOTDIE_HI		BIT(6)
48 #define   TPS6131X_REG_4_HOTDIE_LO		BIT(5)
49 #define   TPS6131X_REG_4_ILIM			BIT(4)
50 #define   TPS6131X_REG_4_INDC			GENMASK(3, 0)
51 #define   TPS6131X_REG_4_INDC_SHIFT		0
52 
53 #define TPS6131X_REG_5				0x05
54 #define   TPS6131X_REG_5_SELFCAL		BIT(7)
55 #define   TPS6131X_REG_5_ENPSM			BIT(6)
56 #define   TPS6131X_REG_5_STSTRB1_DIR		BIT(5)
57 #define   TPS6131X_REG_5_GPIO			BIT(4)
58 #define   TPS6131X_REG_5_GPIOTYPE		BIT(3)
59 #define   TPS6131X_REG_5_ENLED3			BIT(2)
60 #define   TPS6131X_REG_5_ENLED2			BIT(1)
61 #define   TPS6131X_REG_5_ENLED1			BIT(0)
62 
63 #define TPS6131X_REG_6				0x06
64 #define   TPS6131X_REG_6_ENTS			BIT(7)
65 #define   TPS6131X_REG_6_LEDHOT			BIT(6)
66 #define   TPS6131X_REG_6_LEDWARN		BIT(5)
67 #define   TPS6131X_REG_6_LEDHDR			BIT(4)
68 #define   TPS6131X_REG_6_OV			GENMASK(3, 0)
69 #define   TPS6131X_REG_6_OV_SHIFT		0
70 
71 #define TPS6131X_REG_7				0x07
72 #define   TPS6131X_REG_7_ENBATMON		BIT(7)
73 #define   TPS6131X_REG_7_BATDROOP		GENMASK(6, 4)
74 #define   TPS6131X_REG_7_BATDROOP_SHIFT		4
75 #define   TPS6131X_REG_7_REVID			GENMASK(2, 0)
76 #define   TPS6131X_REG_7_REVID_SHIFT		0
77 
78 #define TPS6131X_MAX_CHANNELS			3
79 
80 #define TPS6131X_FLASH_MAX_I_CHAN13_MA		400
81 #define TPS6131X_FLASH_MAX_I_CHAN2_MA		800
82 #define TPS6131X_FLASH_STEP_I_MA		25
83 
84 #define TPS6131X_TORCH_MAX_I_CHAN13_MA		175
85 #define TPS6131X_TORCH_MAX_I_CHAN2_MA		175
86 #define TPS6131X_TORCH_STEP_I_MA		25
87 
88 /* The torch watchdog timer must be refreshed within an interval of 13 seconds. */
89 #define TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES msecs_to_jiffies(10000)
90 
91 #define UA_TO_MA(UA)				((UA) / 1000)
92 
93 enum tps6131x_mode {
94 	TPS6131X_MODE_SHUTDOWN = 0x0,
95 	TPS6131X_MODE_TORCH = 0x1,
96 	TPS6131X_MODE_FLASH = 0x2,
97 };
98 
99 struct tps6131x {
100 	struct device *dev;
101 	struct regmap *regmap;
102 	struct gpio_desc *reset_gpio;
103 	/*
104 	 * Registers 0, 1, 2, and 3 control parts of the controller that are not completely
105 	 * independent of each other. Since some operations require the registers to be written in
106 	 * a specific order to avoid unwanted side effects, they are synchronized with a lock.
107 	 */
108 	struct mutex lock; /* Hardware access lock for register 0, 1, 2 and 3 */
109 	struct delayed_work torch_refresh_work;
110 	bool valley_current_limit;
111 	bool chan1_en;
112 	bool chan2_en;
113 	bool chan3_en;
114 	struct fwnode_handle *led_node;
115 	u32 max_flash_current_ma;
116 	u32 step_flash_current_ma;
117 	u32 max_torch_current_ma;
118 	u32 step_torch_current_ma;
119 	u32 max_timeout_us;
120 	struct led_classdev_flash fled_cdev;
121 	struct v4l2_flash *v4l2_flash;
122 };
123 
fled_cdev_to_tps6131x(struct led_classdev_flash * fled_cdev)124 static struct tps6131x *fled_cdev_to_tps6131x(struct led_classdev_flash *fled_cdev)
125 {
126 	return container_of(fled_cdev, struct tps6131x, fled_cdev);
127 }
128 
129 /*
130  * Register contents after a power on/reset. These values cannot be changed.
131  */
132 
133 #define TPS6131X_DCLC2_50MA	     2
134 #define TPS6131X_DCLC13_25MA	     1
135 #define TPS6131X_FC2_400MA	     16
136 #define TPS6131X_FC13_200MA	     8
137 #define TPS6131X_STIM_0_579MS_1_37MS 6
138 #define TPS6131X_SELSTIM_RANGE0	     0
139 #define TPS6131X_INDC_OFF	     0
140 #define TPS6131X_OV_4950MV	     9
141 #define TPS6131X_BATDROOP_150MV	     4
142 
143 static const struct reg_default tps6131x_regmap_defaults[] = {
144 	{ TPS6131X_REG_0, (TPS6131X_DCLC13_25MA << TPS6131X_REG_0_DCLC13_SHIFT) |
145 				  (TPS6131X_DCLC2_50MA << TPS6131X_REG_0_DCLC2_SHIFT) },
146 	{ TPS6131X_REG_1, (TPS6131X_MODE_SHUTDOWN << TPS6131X_REG_1_MODE_SHIFT) |
147 				  (TPS6131X_FC2_400MA << TPS6131X_REG_1_FC2_SHIFT) },
148 	{ TPS6131X_REG_2, (TPS6131X_MODE_SHUTDOWN << TPS6131X_REG_2_MODE_SHIFT) |
149 				  (TPS6131X_FC13_200MA << TPS6131X_REG_2_FC13_SHIFT) },
150 	{ TPS6131X_REG_3, (TPS6131X_STIM_0_579MS_1_37MS << TPS6131X_REG_3_STIM_SHIFT) |
151 				  (TPS6131X_SELSTIM_RANGE0 << TPS6131X_REG_3_SELSTIM_TO) |
152 				  TPS6131X_REG_3_TXMASK },
153 	{ TPS6131X_REG_4, (TPS6131X_INDC_OFF << TPS6131X_REG_4_INDC_SHIFT) },
154 	{ TPS6131X_REG_5, TPS6131X_REG_5_ENPSM | TPS6131X_REG_5_STSTRB1_DIR |
155 				  TPS6131X_REG_5_GPIOTYPE | TPS6131X_REG_5_ENLED2 },
156 	{ TPS6131X_REG_6, (TPS6131X_OV_4950MV << TPS6131X_REG_6_OV_SHIFT) },
157 	{ TPS6131X_REG_7, (TPS6131X_BATDROOP_150MV << TPS6131X_REG_7_BATDROOP_SHIFT) },
158 };
159 
160 /*
161  * These registers contain flags that are reset when read.
162  */
tps6131x_regmap_precious(struct device * dev,unsigned int reg)163 static bool tps6131x_regmap_precious(struct device *dev, unsigned int reg)
164 {
165 	switch (reg) {
166 	case TPS6131X_REG_3:
167 	case TPS6131X_REG_4:
168 	case TPS6131X_REG_6:
169 		return true;
170 	default:
171 		return false;
172 	}
173 }
174 
175 static const struct regmap_config tps6131x_regmap = {
176 	.reg_bits = 8,
177 	.val_bits = 8,
178 	.max_register = TPS6131X_REG_7,
179 	.reg_defaults = tps6131x_regmap_defaults,
180 	.num_reg_defaults = ARRAY_SIZE(tps6131x_regmap_defaults),
181 	.cache_type = REGCACHE_FLAT,
182 	.precious_reg = &tps6131x_regmap_precious,
183 };
184 
185 struct tps6131x_timer_config {
186 	u8 val;
187 	u8 range;
188 	u32 time_us;
189 };
190 
191 static const struct tps6131x_timer_config tps6131x_timer_configs[] = {
192 	{ .val = 0, .range = 1, .time_us = 5300 },
193 	{ .val = 1, .range = 1, .time_us = 10700 },
194 	{ .val = 2, .range = 1, .time_us = 16000 },
195 	{ .val = 3, .range = 1, .time_us = 21300 },
196 	{ .val = 4, .range = 1, .time_us = 26600 },
197 	{ .val = 5, .range = 1, .time_us = 32000 },
198 	{ .val = 6, .range = 1, .time_us = 37300 },
199 	{ .val = 0, .range = 0, .time_us = 68200 },
200 	{ .val = 7, .range = 1, .time_us = 71500 },
201 	{ .val = 1, .range = 0, .time_us = 102200 },
202 	{ .val = 2, .range = 0, .time_us = 136300 },
203 	{ .val = 3, .range = 0, .time_us = 170400 },
204 	{ .val = 4, .range = 0, .time_us = 204500 },
205 	{ .val = 5, .range = 0, .time_us = 340800 },
206 	{ .val = 6, .range = 0, .time_us = 579300 },
207 	{ .val = 7, .range = 0, .time_us = 852000 },
208 };
209 
tps6131x_find_closest_timer_config(u32 timeout_us)210 static const struct tps6131x_timer_config *tps6131x_find_closest_timer_config(u32 timeout_us)
211 {
212 	const struct tps6131x_timer_config *timer_config = &tps6131x_timer_configs[0];
213 	u32 diff, min_diff = U32_MAX;
214 	int i;
215 
216 	for (i = 0; i < ARRAY_SIZE(tps6131x_timer_configs); i++) {
217 		diff = abs(tps6131x_timer_configs[i].time_us - timeout_us);
218 		if (diff < min_diff) {
219 			timer_config = &tps6131x_timer_configs[i];
220 			min_diff = diff;
221 			if (!min_diff)
222 				break;
223 		}
224 	}
225 
226 	return timer_config;
227 }
228 
tps6131x_reset_chip(struct tps6131x * tps6131x)229 static int tps6131x_reset_chip(struct tps6131x *tps6131x)
230 {
231 	int ret;
232 
233 	if (tps6131x->reset_gpio) {
234 		gpiod_set_value_cansleep(tps6131x->reset_gpio, 1);
235 		fsleep(10);
236 		gpiod_set_value_cansleep(tps6131x->reset_gpio, 0);
237 		fsleep(100);
238 	} else {
239 		ret = regmap_update_bits(tps6131x->regmap, TPS6131X_REG_0, TPS6131X_REG_0_RESET,
240 					 TPS6131X_REG_0_RESET);
241 		if (ret)
242 			return ret;
243 
244 		fsleep(100);
245 
246 		ret = regmap_update_bits(tps6131x->regmap, TPS6131X_REG_0, TPS6131X_REG_0_RESET, 0);
247 		if (ret)
248 			return ret;
249 	}
250 
251 	return 0;
252 }
253 
tps6131x_init_chip(struct tps6131x * tps6131x)254 static int tps6131x_init_chip(struct tps6131x *tps6131x)
255 {
256 	u32 val;
257 	int ret;
258 
259 	val = tps6131x->valley_current_limit ? TPS6131X_REG_4_ILIM : 0;
260 
261 	ret = regmap_write(tps6131x->regmap, TPS6131X_REG_4, val);
262 	if (ret)
263 		return ret;
264 
265 	val = TPS6131X_REG_5_ENPSM | TPS6131X_REG_5_STSTRB1_DIR | TPS6131X_REG_5_GPIOTYPE;
266 
267 	if (tps6131x->chan1_en)
268 		val |= TPS6131X_REG_5_ENLED1;
269 
270 	if (tps6131x->chan2_en)
271 		val |= TPS6131X_REG_5_ENLED2;
272 
273 	if (tps6131x->chan3_en)
274 		val |= TPS6131X_REG_5_ENLED3;
275 
276 	ret = regmap_write(tps6131x->regmap, TPS6131X_REG_5, val);
277 	if (ret)
278 		return ret;
279 
280 	val = TPS6131X_REG_6_ENTS;
281 
282 	ret = regmap_write(tps6131x->regmap, TPS6131X_REG_6, val);
283 	if (ret)
284 		return ret;
285 
286 	return 0;
287 }
288 
tps6131x_set_mode(struct tps6131x * tps6131x,enum tps6131x_mode mode,bool force)289 static int tps6131x_set_mode(struct tps6131x *tps6131x, enum tps6131x_mode mode, bool force)
290 {
291 	u8 val = mode << TPS6131X_REG_1_MODE_SHIFT;
292 
293 	return regmap_update_bits_base(tps6131x->regmap, TPS6131X_REG_1, TPS6131X_REG_1_MODE, val,
294 				       NULL, false, force);
295 }
296 
tps6131x_torch_refresh_handler(struct work_struct * work)297 static void tps6131x_torch_refresh_handler(struct work_struct *work)
298 {
299 	struct tps6131x *tps6131x = container_of(work, struct tps6131x, torch_refresh_work.work);
300 	int ret;
301 
302 	guard(mutex)(&tps6131x->lock);
303 
304 	ret = tps6131x_set_mode(tps6131x, TPS6131X_MODE_TORCH, true);
305 	if (ret < 0) {
306 		dev_err(tps6131x->dev, "Failed to refresh torch watchdog timer\n");
307 		return;
308 	}
309 
310 	schedule_delayed_work(&tps6131x->torch_refresh_work,
311 			      TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES);
312 }
313 
tps6131x_brightness_set(struct led_classdev * cdev,enum led_brightness brightness)314 static int tps6131x_brightness_set(struct led_classdev *cdev, enum led_brightness brightness)
315 {
316 	struct led_classdev_flash *fled_cdev = lcdev_to_flcdev(cdev);
317 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
318 	u32 num_chans, steps_chan13, steps_chan2, steps_remaining;
319 	u8 reg0;
320 	int ret;
321 
322 	cancel_delayed_work_sync(&tps6131x->torch_refresh_work);
323 
324 	/*
325 	 * The brightness parameter uses the number of current steps as the unit (not the current
326 	 * value itself). Since the reported step size can vary depending on the configuration,
327 	 * this value must be converted into actual register steps.
328 	 */
329 	steps_remaining = (brightness * tps6131x->step_torch_current_ma) / TPS6131X_TORCH_STEP_I_MA;
330 
331 	num_chans = tps6131x->chan1_en + tps6131x->chan2_en + tps6131x->chan3_en;
332 
333 	/*
334 	 * The currents are distributed as evenly as possible across the activated channels.
335 	 * Since channels 1 and 3 share the same register setting, they always use the same current
336 	 * value. Channel 2 supports higher currents and thus takes over the remaining additional
337 	 * portion that cannot be covered by the other channels.
338 	 */
339 	steps_chan13 = min_t(u32, steps_remaining / num_chans,
340 			     TPS6131X_TORCH_MAX_I_CHAN13_MA / TPS6131X_TORCH_STEP_I_MA);
341 	if (tps6131x->chan1_en)
342 		steps_remaining -= steps_chan13;
343 	if (tps6131x->chan3_en)
344 		steps_remaining -= steps_chan13;
345 
346 	steps_chan2 = min_t(u32, steps_remaining,
347 			    TPS6131X_TORCH_MAX_I_CHAN2_MA / TPS6131X_TORCH_STEP_I_MA);
348 
349 	guard(mutex)(&tps6131x->lock);
350 
351 	reg0 = (steps_chan13 << TPS6131X_REG_0_DCLC13_SHIFT) |
352 	       (steps_chan2 << TPS6131X_REG_0_DCLC2_SHIFT);
353 	ret = regmap_update_bits(tps6131x->regmap, TPS6131X_REG_0,
354 				 TPS6131X_REG_0_DCLC13 | TPS6131X_REG_0_DCLC2, reg0);
355 	if (ret < 0)
356 		return ret;
357 
358 	ret = tps6131x_set_mode(tps6131x, brightness ? TPS6131X_MODE_TORCH : TPS6131X_MODE_SHUTDOWN,
359 				true);
360 	if (ret < 0)
361 		return ret;
362 
363 	/*
364 	 * In order to use both the flash and the video light functions purely via the I2C
365 	 * interface, STRB1 must be low. If STRB1 is low, then the video light watchdog timer
366 	 * is also active, which puts the device into the shutdown state after around 13 seconds.
367 	 * To prevent this, the mode must be refreshed within the watchdog timeout.
368 	 */
369 	if (brightness)
370 		schedule_delayed_work(&tps6131x->torch_refresh_work,
371 				      TPS6131X_TORCH_REFRESH_INTERVAL_JIFFIES);
372 
373 	return 0;
374 }
375 
tps6131x_strobe_set(struct led_classdev_flash * fled_cdev,bool state)376 static int tps6131x_strobe_set(struct led_classdev_flash *fled_cdev, bool state)
377 {
378 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
379 	int ret;
380 
381 	guard(mutex)(&tps6131x->lock);
382 
383 	ret = tps6131x_set_mode(tps6131x, state ? TPS6131X_MODE_FLASH : TPS6131X_MODE_SHUTDOWN,
384 				true);
385 	if (ret < 0)
386 		return ret;
387 
388 	if (state) {
389 		ret = regmap_update_bits_base(tps6131x->regmap, TPS6131X_REG_3, TPS6131X_REG_3_SFT,
390 					      TPS6131X_REG_3_SFT, NULL, false, true);
391 		if (ret)
392 			return ret;
393 	}
394 
395 	ret = regmap_update_bits_base(tps6131x->regmap, TPS6131X_REG_3, TPS6131X_REG_3_SFT, 0, NULL,
396 				      false, true);
397 	if (ret)
398 		return ret;
399 
400 	return 0;
401 }
402 
tps6131x_flash_brightness_set(struct led_classdev_flash * fled_cdev,u32 brightness)403 static int tps6131x_flash_brightness_set(struct led_classdev_flash *fled_cdev, u32 brightness)
404 {
405 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
406 	u32 num_chans;
407 	u32 steps_chan13, steps_chan2;
408 	u32 steps_remaining;
409 	int ret;
410 
411 	steps_remaining = brightness / TPS6131X_FLASH_STEP_I_MA;
412 	num_chans = tps6131x->chan1_en + tps6131x->chan2_en + tps6131x->chan3_en;
413 	steps_chan13 = min_t(u32, steps_remaining / num_chans,
414 			     TPS6131X_FLASH_MAX_I_CHAN13_MA / TPS6131X_FLASH_STEP_I_MA);
415 	if (tps6131x->chan1_en)
416 		steps_remaining -= steps_chan13;
417 	if (tps6131x->chan3_en)
418 		steps_remaining -= steps_chan13;
419 	steps_chan2 = min_t(u32, steps_remaining,
420 			    TPS6131X_FLASH_MAX_I_CHAN2_MA / TPS6131X_FLASH_STEP_I_MA);
421 
422 	guard(mutex)(&tps6131x->lock);
423 
424 	ret = regmap_update_bits(tps6131x->regmap, TPS6131X_REG_2, TPS6131X_REG_2_FC13,
425 				 steps_chan13 << TPS6131X_REG_2_FC13_SHIFT);
426 	if (ret < 0)
427 		return ret;
428 
429 	ret = regmap_update_bits(tps6131x->regmap, TPS6131X_REG_1, TPS6131X_REG_1_FC2,
430 				 steps_chan2 << TPS6131X_REG_1_FC2_SHIFT);
431 	if (ret < 0)
432 		return ret;
433 
434 	fled_cdev->brightness.val = brightness;
435 
436 	return 0;
437 }
438 
tps6131x_flash_timeout_set(struct led_classdev_flash * fled_cdev,u32 timeout_us)439 static int tps6131x_flash_timeout_set(struct led_classdev_flash *fled_cdev, u32 timeout_us)
440 {
441 	const struct tps6131x_timer_config *timer_config;
442 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
443 	u8 reg3;
444 	int ret;
445 
446 	guard(mutex)(&tps6131x->lock);
447 
448 	timer_config = tps6131x_find_closest_timer_config(timeout_us);
449 
450 	reg3 = timer_config->val << TPS6131X_REG_3_STIM_SHIFT;
451 	if (timer_config->range)
452 		reg3 |= TPS6131X_REG_3_SELSTIM_TO;
453 
454 	ret = regmap_update_bits(tps6131x->regmap, TPS6131X_REG_3,
455 				 TPS6131X_REG_3_STIM | TPS6131X_REG_3_SELSTIM_TO, reg3);
456 	if (ret < 0)
457 		return ret;
458 
459 	fled_cdev->timeout.val = timer_config->time_us;
460 
461 	return 0;
462 }
463 
tps6131x_strobe_get(struct led_classdev_flash * fled_cdev,bool * state)464 static int tps6131x_strobe_get(struct led_classdev_flash *fled_cdev, bool *state)
465 {
466 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
467 	unsigned int reg3;
468 	int ret;
469 
470 	ret = regmap_read_bypassed(tps6131x->regmap, TPS6131X_REG_3, &reg3);
471 	if (ret)
472 		return ret;
473 
474 	*state = !!(reg3 & TPS6131X_REG_3_SFT);
475 
476 	return 0;
477 }
478 
tps6131x_flash_fault_get(struct led_classdev_flash * fled_cdev,u32 * fault)479 static int tps6131x_flash_fault_get(struct led_classdev_flash *fled_cdev, u32 *fault)
480 {
481 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
482 	unsigned int reg3, reg4, reg6;
483 	int ret;
484 
485 	*fault = 0;
486 
487 	ret = regmap_read_bypassed(tps6131x->regmap, TPS6131X_REG_3, &reg3);
488 	if (ret < 0)
489 		return ret;
490 
491 	ret = regmap_read_bypassed(tps6131x->regmap, TPS6131X_REG_4, &reg4);
492 	if (ret < 0)
493 		return ret;
494 
495 	ret = regmap_read_bypassed(tps6131x->regmap, TPS6131X_REG_6, &reg6);
496 	if (ret < 0)
497 		return ret;
498 
499 	if (reg3 & TPS6131X_REG_3_HPFL)
500 		*fault |= LED_FAULT_SHORT_CIRCUIT;
501 
502 	if (reg3 & TPS6131X_REG_3_SELSTIM_TO)
503 		*fault |= LED_FAULT_TIMEOUT;
504 
505 	if (reg4 & TPS6131X_REG_4_HOTDIE_HI)
506 		*fault |= LED_FAULT_OVER_TEMPERATURE;
507 
508 	if (reg6 & (TPS6131X_REG_6_LEDHOT | TPS6131X_REG_6_LEDWARN))
509 		*fault |= LED_FAULT_LED_OVER_TEMPERATURE;
510 
511 	if (!(reg6 & TPS6131X_REG_6_LEDHDR))
512 		*fault |= LED_FAULT_UNDER_VOLTAGE;
513 
514 	if (reg6 & TPS6131X_REG_6_LEDHOT) {
515 		ret = regmap_update_bits_base(tps6131x->regmap, TPS6131X_REG_6,
516 					      TPS6131X_REG_6_LEDHOT, 0, NULL, false, true);
517 		if (ret < 0)
518 			return ret;
519 	}
520 
521 	return 0;
522 }
523 
524 static const struct led_flash_ops flash_ops = {
525 	.flash_brightness_set = tps6131x_flash_brightness_set,
526 	.strobe_set = tps6131x_strobe_set,
527 	.strobe_get = tps6131x_strobe_get,
528 	.timeout_set = tps6131x_flash_timeout_set,
529 	.fault_get = tps6131x_flash_fault_get,
530 };
531 
tps6131x_parse_node(struct tps6131x * tps6131x)532 static int tps6131x_parse_node(struct tps6131x *tps6131x)
533 {
534 	const struct tps6131x_timer_config *timer_config;
535 	struct device *dev = tps6131x->dev;
536 	u32 channels[TPS6131X_MAX_CHANNELS];
537 	u32 current_step_multiplier;
538 	u32 current_ua;
539 	u32 max_current_flash_ma, max_current_torch_ma;
540 	u32 timeout_us;
541 	int num_channels;
542 	int i;
543 	int ret;
544 
545 	tps6131x->valley_current_limit = device_property_read_bool(dev, "ti,valley-current-limit");
546 
547 	tps6131x->led_node = fwnode_get_next_available_child_node(dev->fwnode, NULL);
548 	if (!tps6131x->led_node) {
549 		dev_err(dev, "Missing LED node\n");
550 		return -EINVAL;
551 	}
552 
553 	num_channels = fwnode_property_count_u32(tps6131x->led_node, "led-sources");
554 	if (num_channels <= 0) {
555 		dev_err(dev, "Failed to read led-sources property\n");
556 		return -EINVAL;
557 	}
558 
559 	if (num_channels > TPS6131X_MAX_CHANNELS) {
560 		dev_err(dev, "led-sources count %u exceeds maximum channel count %u\n",
561 			num_channels, TPS6131X_MAX_CHANNELS);
562 		return -EINVAL;
563 	}
564 
565 	ret = fwnode_property_read_u32_array(tps6131x->led_node, "led-sources", channels,
566 					     num_channels);
567 	if (ret < 0) {
568 		dev_err(dev, "Failed to read led-sources property\n");
569 		return ret;
570 	}
571 
572 	max_current_flash_ma = 0;
573 	max_current_torch_ma = 0;
574 	for (i = 0; i < num_channels; i++) {
575 		switch (channels[i]) {
576 		case 1:
577 			tps6131x->chan1_en = true;
578 			max_current_flash_ma += TPS6131X_FLASH_MAX_I_CHAN13_MA;
579 			max_current_torch_ma += TPS6131X_TORCH_MAX_I_CHAN13_MA;
580 			break;
581 		case 2:
582 			tps6131x->chan2_en = true;
583 			max_current_flash_ma += TPS6131X_FLASH_MAX_I_CHAN2_MA;
584 			max_current_torch_ma += TPS6131X_TORCH_MAX_I_CHAN2_MA;
585 			break;
586 		case 3:
587 			tps6131x->chan3_en = true;
588 			max_current_flash_ma += TPS6131X_FLASH_MAX_I_CHAN13_MA;
589 			max_current_torch_ma += TPS6131X_TORCH_MAX_I_CHAN13_MA;
590 			break;
591 		default:
592 			dev_err(dev, "led-source out of range [1-3]\n");
593 			return -EINVAL;
594 		}
595 	}
596 
597 	/*
598 	 * If only channels 1 and 3 are used, the step size is doubled because the two channels
599 	 * share the same current control register.
600 	 */
601 	current_step_multiplier =
602 		(tps6131x->chan1_en && tps6131x->chan3_en && !tps6131x->chan2_en) ? 2 : 1;
603 	tps6131x->step_flash_current_ma = current_step_multiplier * TPS6131X_FLASH_STEP_I_MA;
604 	tps6131x->step_torch_current_ma = current_step_multiplier * TPS6131X_TORCH_STEP_I_MA;
605 
606 	ret = fwnode_property_read_u32(tps6131x->led_node, "led-max-microamp", &current_ua);
607 	if (ret < 0) {
608 		dev_err(dev, "Failed to read led-max-microamp property\n");
609 		return ret;
610 	}
611 
612 	tps6131x->max_torch_current_ma = UA_TO_MA(current_ua);
613 
614 	if (!tps6131x->max_torch_current_ma ||
615 	    tps6131x->max_torch_current_ma > max_current_torch_ma ||
616 	    (tps6131x->max_torch_current_ma % tps6131x->step_torch_current_ma)) {
617 		dev_err(dev, "led-max-microamp out of range or not a multiple of %u\n",
618 			tps6131x->step_torch_current_ma);
619 		return -EINVAL;
620 	}
621 
622 	ret = fwnode_property_read_u32(tps6131x->led_node, "flash-max-microamp", &current_ua);
623 	if (ret < 0) {
624 		dev_err(dev, "Failed to read flash-max-microamp property\n");
625 		return ret;
626 	}
627 
628 	tps6131x->max_flash_current_ma = UA_TO_MA(current_ua);
629 
630 	if (!tps6131x->max_flash_current_ma ||
631 	    tps6131x->max_flash_current_ma > max_current_flash_ma ||
632 	    (tps6131x->max_flash_current_ma % tps6131x->step_flash_current_ma)) {
633 		dev_err(dev, "flash-max-microamp out of range or not a multiple of %u\n",
634 			tps6131x->step_flash_current_ma);
635 		return -EINVAL;
636 	}
637 
638 	ret = fwnode_property_read_u32(tps6131x->led_node, "flash-max-timeout-us", &timeout_us);
639 	if (ret < 0) {
640 		dev_err(dev, "Failed to read flash-max-timeout-us property\n");
641 		return ret;
642 	}
643 
644 	timer_config = tps6131x_find_closest_timer_config(timeout_us);
645 	tps6131x->max_timeout_us = timer_config->time_us;
646 
647 	if (tps6131x->max_timeout_us != timeout_us)
648 		dev_warn(dev, "flash-max-timeout-us %u not supported (using %u)\n", timeout_us,
649 			 tps6131x->max_timeout_us);
650 
651 	return 0;
652 }
653 
tps6131x_led_class_setup(struct tps6131x * tps6131x)654 static int tps6131x_led_class_setup(struct tps6131x *tps6131x)
655 {
656 	const struct tps6131x_timer_config *timer_config;
657 	struct led_classdev *led_cdev;
658 	struct led_flash_setting *setting;
659 	struct led_init_data init_data = {};
660 	int ret;
661 
662 	tps6131x->fled_cdev.ops = &flash_ops;
663 
664 	setting = &tps6131x->fled_cdev.timeout;
665 	timer_config = tps6131x_find_closest_timer_config(0);
666 	setting->min = timer_config->time_us;
667 	setting->max = tps6131x->max_timeout_us;
668 	setting->step = 1; /* Only some specific time periods are supported. No fixed step size. */
669 	setting->val = setting->min;
670 
671 	setting = &tps6131x->fled_cdev.brightness;
672 	setting->min = tps6131x->step_flash_current_ma;
673 	setting->max = tps6131x->max_flash_current_ma;
674 	setting->step = tps6131x->step_flash_current_ma;
675 	setting->val = setting->min;
676 
677 	led_cdev = &tps6131x->fled_cdev.led_cdev;
678 	led_cdev->brightness_set_blocking = tps6131x_brightness_set;
679 	led_cdev->max_brightness = tps6131x->max_torch_current_ma;
680 	led_cdev->flags |= LED_DEV_CAP_FLASH;
681 
682 	init_data.fwnode = tps6131x->led_node;
683 	init_data.devicename = NULL;
684 	init_data.default_label = NULL;
685 	init_data.devname_mandatory = false;
686 
687 	ret = devm_led_classdev_flash_register_ext(tps6131x->dev, &tps6131x->fled_cdev,
688 						   &init_data);
689 	if (ret)
690 		return ret;
691 
692 	return 0;
693 }
694 
tps6131x_flash_external_strobe_set(struct v4l2_flash * v4l2_flash,bool enable)695 static int tps6131x_flash_external_strobe_set(struct v4l2_flash *v4l2_flash, bool enable)
696 {
697 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;
698 	struct tps6131x *tps6131x = fled_cdev_to_tps6131x(fled_cdev);
699 
700 	guard(mutex)(&tps6131x->lock);
701 
702 	return tps6131x_set_mode(tps6131x, enable ? TPS6131X_MODE_FLASH : TPS6131X_MODE_SHUTDOWN,
703 				 false);
704 }
705 
706 static const struct v4l2_flash_ops tps6131x_v4l2_flash_ops = {
707 	.external_strobe_set = tps6131x_flash_external_strobe_set,
708 };
709 
tps6131x_v4l2_setup(struct tps6131x * tps6131x)710 static int tps6131x_v4l2_setup(struct tps6131x *tps6131x)
711 {
712 	struct v4l2_flash_config v4l2_cfg = { 0 };
713 	struct led_flash_setting *intensity = &v4l2_cfg.intensity;
714 
715 	intensity->min = tps6131x->step_torch_current_ma;
716 	intensity->max = tps6131x->max_torch_current_ma;
717 	intensity->step = tps6131x->step_torch_current_ma;
718 	intensity->val = intensity->min;
719 
720 	strscpy(v4l2_cfg.dev_name, tps6131x->fled_cdev.led_cdev.dev->kobj.name,
721 		sizeof(v4l2_cfg.dev_name));
722 
723 	v4l2_cfg.has_external_strobe = true;
724 	v4l2_cfg.flash_faults = LED_FAULT_TIMEOUT | LED_FAULT_OVER_TEMPERATURE |
725 				LED_FAULT_SHORT_CIRCUIT | LED_FAULT_UNDER_VOLTAGE |
726 				LED_FAULT_LED_OVER_TEMPERATURE;
727 
728 	tps6131x->v4l2_flash = v4l2_flash_init(tps6131x->dev, tps6131x->led_node,
729 					       &tps6131x->fled_cdev, &tps6131x_v4l2_flash_ops,
730 					       &v4l2_cfg);
731 	if (IS_ERR(tps6131x->v4l2_flash)) {
732 		dev_err(tps6131x->dev, "Failed to initialize v4l2 flash LED\n");
733 		return PTR_ERR(tps6131x->v4l2_flash);
734 	}
735 
736 	return 0;
737 }
738 
tps6131x_probe(struct i2c_client * client)739 static int tps6131x_probe(struct i2c_client *client)
740 {
741 	struct tps6131x *tps6131x;
742 	int ret;
743 
744 	tps6131x = devm_kzalloc(&client->dev, sizeof(*tps6131x), GFP_KERNEL);
745 	if (!tps6131x)
746 		return -ENOMEM;
747 
748 	tps6131x->dev = &client->dev;
749 	i2c_set_clientdata(client, tps6131x);
750 	mutex_init(&tps6131x->lock);
751 	INIT_DELAYED_WORK(&tps6131x->torch_refresh_work, tps6131x_torch_refresh_handler);
752 
753 	ret = tps6131x_parse_node(tps6131x);
754 	if (ret)
755 		return ret;
756 
757 	tps6131x->regmap = devm_regmap_init_i2c(client, &tps6131x_regmap);
758 	if (IS_ERR(tps6131x->regmap)) {
759 		ret = PTR_ERR(tps6131x->regmap);
760 		return dev_err_probe(&client->dev, ret, "Failed to allocate register map\n");
761 	}
762 
763 	tps6131x->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
764 	if (IS_ERR(tps6131x->reset_gpio)) {
765 		ret = PTR_ERR(tps6131x->reset_gpio);
766 		return dev_err_probe(&client->dev, ret, "Failed to get reset GPIO\n");
767 	}
768 
769 	ret = tps6131x_reset_chip(tps6131x);
770 	if (ret)
771 		return dev_err_probe(&client->dev, ret, "Failed to reset LED controller\n");
772 
773 	ret = tps6131x_init_chip(tps6131x);
774 	if (ret)
775 		return dev_err_probe(&client->dev, ret, "Failed to initialize LED controller\n");
776 
777 	ret = tps6131x_led_class_setup(tps6131x);
778 	if (ret)
779 		return dev_err_probe(&client->dev, ret, "Failed to setup LED class\n");
780 
781 	ret = tps6131x_v4l2_setup(tps6131x);
782 	if (ret)
783 		return dev_err_probe(&client->dev, ret, "Failed to setup v4l2 flash\n");
784 
785 	return 0;
786 }
787 
tps6131x_remove(struct i2c_client * client)788 static void tps6131x_remove(struct i2c_client *client)
789 {
790 	struct tps6131x *tps6131x = i2c_get_clientdata(client);
791 
792 	v4l2_flash_release(tps6131x->v4l2_flash);
793 
794 	cancel_delayed_work_sync(&tps6131x->torch_refresh_work);
795 }
796 
797 static const struct of_device_id of_tps6131x_leds_match[] = {
798 	{ .compatible = "ti,tps61310" },
799 	{}
800 };
801 MODULE_DEVICE_TABLE(of, of_tps6131x_leds_match);
802 
803 static struct i2c_driver tps6131x_i2c_driver = {
804 	.driver = {
805 		.name = "tps6131x",
806 		.of_match_table = of_tps6131x_leds_match,
807 	},
808 	.probe = tps6131x_probe,
809 	.remove = tps6131x_remove,
810 };
811 module_i2c_driver(tps6131x_i2c_driver);
812 
813 MODULE_DESCRIPTION("Texas Instruments TPS6131X flash LED driver");
814 MODULE_AUTHOR("Matthias Fend <matthias.fend@emfend.at>");
815 MODULE_LICENSE("GPL");
816