1 // SPDX-License-Identifier: GPL-2.0-only
3  *	LED Flash class driver for the AAT1290
4  *	1.5A Step-Up Current Regulator for Flash LEDs
13 #include <linux/led-class-flash.h>
21 #include <media/v4l2-flash-led-class.h>
50 	/* maximum LED current in movie mode */
52 	/* maximum LED current in flash mode */
54 	/* maximum flash timeout */
58 	/* max LED brightness level */
68 	/* corresponding LED Flash class device */
70 	/* V4L2 Flash device */
95 static void aat1290_as2cwire_write(struct aat1290_led *led, int addr, int value)  in aat1290_as2cwire_write()  argument
99 	gpiod_direction_output(led->gpio_fl_en, 0);  in aat1290_as2cwire_write()
100 	gpiod_direction_output(led->gpio_en_set, 0);  in aat1290_as2cwire_write()
107 		gpiod_direction_output(led->gpio_en_set, 0);  in aat1290_as2cwire_write()
109 		gpiod_direction_output(led->gpio_en_set, 1);  in aat1290_as2cwire_write()
117 		gpiod_direction_output(led->gpio_en_set, 0);  in aat1290_as2cwire_write()
119 		gpiod_direction_output(led->gpio_en_set, 1);  in aat1290_as2cwire_write()
125 static void aat1290_set_flash_safety_timer(struct aat1290_led *led,  in aat1290_set_flash_safety_timer()  argument
128 	struct led_classdev_flash *fled_cdev = &led->fled_cdev;  in aat1290_set_flash_safety_timer()
129 	struct led_flash_setting *flash_tm = &fled_cdev->timeout;  in aat1290_set_flash_safety_timer()
130 	int flash_tm_reg = AAT1290_FLASH_TM_NUM_LEVELS -  in aat1290_set_flash_safety_timer()
131 				(micro_sec / flash_tm->step) + 1;  in aat1290_set_flash_safety_timer()
133 	aat1290_as2cwire_write(led, AAT1290_FLASH_SAFETY_TIMER_ADDR,  in aat1290_set_flash_safety_timer()
137 /* LED subsystem callbacks */
143 	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);  in aat1290_led_brightness_set()  local
145 	mutex_lock(&led->lock);  in aat1290_led_brightness_set()
148 		gpiod_direction_output(led->gpio_fl_en, 0);  in aat1290_led_brightness_set()
149 		gpiod_direction_output(led->gpio_en_set, 0);  in aat1290_led_brightness_set()
150 		led->movie_mode = false;  in aat1290_led_brightness_set()
152 		if (!led->movie_mode) {  in aat1290_led_brightness_set()
153 			aat1290_as2cwire_write(led,  in aat1290_led_brightness_set()
156 			led->movie_mode = true;  in aat1290_led_brightness_set()
159 		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CURRENT_ADDR,  in aat1290_led_brightness_set()
160 				AAT1290_MAX_MM_CURR_PERCENT_0 - brightness);  in aat1290_led_brightness_set()
161 		aat1290_as2cwire_write(led, AAT1290_MOVIE_MODE_CONFIG_ADDR,  in aat1290_led_brightness_set()
165 	mutex_unlock(&led->lock);  in aat1290_led_brightness_set()
174 	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);  in aat1290_led_flash_strobe_set()  local
175 	struct led_classdev *led_cdev = &fled_cdev->led_cdev;  in aat1290_led_flash_strobe_set()
176 	struct led_flash_setting *timeout = &fled_cdev->timeout;  in aat1290_led_flash_strobe_set()
178 	mutex_lock(&led->lock);  in aat1290_led_flash_strobe_set()
181 		aat1290_set_flash_safety_timer(led, timeout->val);  in aat1290_led_flash_strobe_set()
182 		gpiod_direction_output(led->gpio_fl_en, 1);  in aat1290_led_flash_strobe_set()
184 		gpiod_direction_output(led->gpio_fl_en, 0);  in aat1290_led_flash_strobe_set()
185 		gpiod_direction_output(led->gpio_en_set, 0);  in aat1290_led_flash_strobe_set()
189 	 * To reenter movie mode after a flash event the part must be cycled  in aat1290_led_flash_strobe_set()
194 	led_cdev->brightness = 0;  in aat1290_led_flash_strobe_set()
195 	led->movie_mode = false;  in aat1290_led_flash_strobe_set()
197 	mutex_unlock(&led->lock);  in aat1290_led_flash_strobe_set()
206 	 * Don't do anything - flash timeout is cached in the led-class-flash  in aat1290_led_flash_timeout_set()
214 static int aat1290_led_parse_dt(struct aat1290_led *led,  in aat1290_led_parse_dt()  argument
218 	struct device *dev = &led->pdev->dev;  in aat1290_led_parse_dt()
224 	led->gpio_fl_en = devm_gpiod_get(dev, "flen", GPIOD_ASIS);  in aat1290_led_parse_dt()
225 	if (IS_ERR(led->gpio_fl_en)) {  in aat1290_led_parse_dt()
226 		ret = PTR_ERR(led->gpio_fl_en);  in aat1290_led_parse_dt()
231 	led->gpio_en_set = devm_gpiod_get(dev, "enset", GPIOD_ASIS);  in aat1290_led_parse_dt()
232 	if (IS_ERR(led->gpio_en_set)) {  in aat1290_led_parse_dt()
233 		ret = PTR_ERR(led->gpio_en_set);  in aat1290_led_parse_dt()
239 	pinctrl = devm_pinctrl_get_select_default(&led->pdev->dev);  in aat1290_led_parse_dt()
241 		cfg->has_external_strobe = false;  in aat1290_led_parse_dt()
245 		cfg->has_external_strobe = true;  in aat1290_led_parse_dt()
252 		dev_err(dev, "No DT child node found for connected LED.\n");  in aat1290_led_parse_dt()
253 		return -EINVAL;  in aat1290_led_parse_dt()
256 	ret = of_property_read_u32(child_node, "led-max-microamp",  in aat1290_led_parse_dt()
257 				&cfg->max_mm_current);  in aat1290_led_parse_dt()
259 	 * led-max-microamp will default to 1/20 of flash-max-microamp  in aat1290_led_parse_dt()
264 			"led-max-microamp DT property missing\n");  in aat1290_led_parse_dt()
266 	ret = of_property_read_u32(child_node, "flash-max-microamp",  in aat1290_led_parse_dt()
267 				&cfg->max_flash_current);  in aat1290_led_parse_dt()
270 			"flash-max-microamp DT property missing\n");  in aat1290_led_parse_dt()
274 	ret = of_property_read_u32(child_node, "flash-max-timeout-us",  in aat1290_led_parse_dt()
275 				&cfg->max_flash_tm);  in aat1290_led_parse_dt()
278 			"flash-max-timeout-us DT property missing\n");  in aat1290_led_parse_dt()
287 static void aat1290_led_validate_mm_current(struct aat1290_led *led,  in aat1290_led_validate_mm_current()  argument
292 	while (e - b > 1) {  in aat1290_led_validate_mm_current()
293 		i = b + (e - b) / 2;  in aat1290_led_validate_mm_current()
294 		if (cfg->max_mm_current < led->mm_current_scale[i])  in aat1290_led_validate_mm_current()
300 	cfg->max_mm_current = led->mm_current_scale[b];  in aat1290_led_validate_mm_current()
301 	cfg->max_brightness = b + 1;  in aat1290_led_validate_mm_current()
304 static int init_mm_current_scale(struct aat1290_led *led,  in init_mm_current_scale()  argument
312 			AAT1290_MAX_MM_CURRENT(cfg->max_flash_current);  in init_mm_current_scale()
314 	led->mm_current_scale = devm_kzalloc(&led->pdev->dev,  in init_mm_current_scale()
317 	if (!led->mm_current_scale)  in init_mm_current_scale()
318 		return -ENOMEM;  in init_mm_current_scale()
321 		led->mm_current_scale[i] = max_mm_current *  in init_mm_current_scale()
327 static int aat1290_led_get_configuration(struct aat1290_led *led,  in aat1290_led_get_configuration()  argument
333 	ret = aat1290_led_parse_dt(led, cfg, sub_node);  in aat1290_led_get_configuration()
337 	 * Init non-linear movie mode current scale basing  in aat1290_led_get_configuration()
338 	 * on the max flash current from led configuration.  in aat1290_led_get_configuration()
340 	ret = init_mm_current_scale(led, cfg);  in aat1290_led_get_configuration()
344 	aat1290_led_validate_mm_current(led, cfg);  in aat1290_led_get_configuration()
348 	devm_kfree(&led->pdev->dev, led->mm_current_scale);  in aat1290_led_get_configuration()
354 static void aat1290_init_flash_timeout(struct aat1290_led *led,  in aat1290_init_flash_timeout()  argument
357 	struct led_classdev_flash *fled_cdev = &led->fled_cdev;  in aat1290_init_flash_timeout()
360 	/* Init flash timeout setting */  in aat1290_init_flash_timeout()
361 	setting = &fled_cdev->timeout;  in aat1290_init_flash_timeout()
362 	setting->min = cfg->max_flash_tm / AAT1290_FLASH_TM_NUM_LEVELS;  in aat1290_init_flash_timeout()
363 	setting->max = cfg->max_flash_tm;  in aat1290_init_flash_timeout()
364 	setting->step = setting->min;  in aat1290_init_flash_timeout()
365 	setting->val = setting->max;  in aat1290_init_flash_timeout()
373 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;  in aat1290_intensity_to_brightness()
374 	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);  in aat1290_intensity_to_brightness()  local
377 	for (i = AAT1290_MM_CURRENT_SCALE_SIZE - 1; i >= 0; --i)  in aat1290_intensity_to_brightness()
378 		if (intensity >= led->mm_current_scale[i])  in aat1290_intensity_to_brightness()
387 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;  in aat1290_brightness_to_intensity()
388 	struct aat1290_led *led = fled_cdev_to_led(fled_cdev);  in aat1290_brightness_to_intensity()  local
390 	return led->mm_current_scale[brightness - 1];  in aat1290_brightness_to_intensity()
396 	struct aat1290_led *led = fled_cdev_to_led(v4l2_flash->fled_cdev);  in aat1290_led_external_strobe_set()  local
397 	struct led_classdev_flash *fled_cdev = v4l2_flash->fled_cdev;  in aat1290_led_external_strobe_set()
398 	struct led_classdev *led_cdev = &fled_cdev->led_cdev;  in aat1290_led_external_strobe_set()
401 	gpiod_direction_output(led->gpio_fl_en, 0);  in aat1290_led_external_strobe_set()
402 	gpiod_direction_output(led->gpio_en_set, 0);  in aat1290_led_external_strobe_set()
404 	led->movie_mode = false;  in aat1290_led_external_strobe_set()
405 	led_cdev->brightness = 0;  in aat1290_led_external_strobe_set()
407 	pinctrl = devm_pinctrl_get_select(&led->pdev->dev,  in aat1290_led_external_strobe_set()
410 		dev_warn(&led->pdev->dev, "Unable to switch strobe source.\n");  in aat1290_led_external_strobe_set()
417 static void aat1290_init_v4l2_flash_config(struct aat1290_led *led,  in aat1290_init_v4l2_flash_config()  argument
421 	struct led_classdev *led_cdev = &led->fled_cdev.led_cdev;  in aat1290_init_v4l2_flash_config()
424 	strscpy(v4l2_sd_cfg->dev_name, led_cdev->dev->kobj.name,  in aat1290_init_v4l2_flash_config()
425 		sizeof(v4l2_sd_cfg->dev_name));  in aat1290_init_v4l2_flash_config()
427 	s = &v4l2_sd_cfg->intensity;  in aat1290_init_v4l2_flash_config()
428 	s->min = led->mm_current_scale[0];  in aat1290_init_v4l2_flash_config()
429 	s->max = led_cfg->max_mm_current;  in aat1290_init_v4l2_flash_config()
430 	s->step = 1;  in aat1290_init_v4l2_flash_config()
431 	s->val = s->max;  in aat1290_init_v4l2_flash_config()
433 	v4l2_sd_cfg->has_external_strobe = led_cfg->has_external_strobe;  in aat1290_init_v4l2_flash_config()
442 static inline void aat1290_init_v4l2_flash_config(struct aat1290_led *led,  in aat1290_init_v4l2_flash_config()  argument
457 	struct device *dev = &pdev->dev;  in aat1290_led_probe()
459 	struct aat1290_led *led;  in aat1290_led_probe()  local
467 	led = devm_kzalloc(dev, sizeof(*led), GFP_KERNEL);  in aat1290_led_probe()
468 	if (!led)  in aat1290_led_probe()
469 		return -ENOMEM;  in aat1290_led_probe()
471 	led->pdev = pdev;  in aat1290_led_probe()
472 	platform_set_drvdata(pdev, led);  in aat1290_led_probe()
474 	fled_cdev = &led->fled_cdev;  in aat1290_led_probe()
475 	fled_cdev->ops = &flash_ops;  in aat1290_led_probe()
476 	led_cdev = &fled_cdev->led_cdev;  in aat1290_led_probe()
478 	ret = aat1290_led_get_configuration(led, &led_cfg, &sub_node);  in aat1290_led_probe()
482 	mutex_init(&led->lock);  in aat1290_led_probe()
484 	/* Initialize LED Flash class device */  in aat1290_led_probe()
485 	led_cdev->brightness_set_blocking = aat1290_led_brightness_set;  in aat1290_led_probe()
486 	led_cdev->max_brightness = led_cfg.max_brightness;  in aat1290_led_probe()
487 	led_cdev->flags |= LED_DEV_CAP_FLASH;  in aat1290_led_probe()
489 	aat1290_init_flash_timeout(led, &led_cfg);  in aat1290_led_probe()
494 	/* Register LED Flash class device */  in aat1290_led_probe()
495 	ret = led_classdev_flash_register_ext(&pdev->dev, fled_cdev,  in aat1290_led_probe()
500 	aat1290_init_v4l2_flash_config(led, &led_cfg, &v4l2_sd_cfg);  in aat1290_led_probe()
502 	/* Create V4L2 Flash subdev. */  in aat1290_led_probe()
503 	led->v4l2_flash = v4l2_flash_init(dev, of_fwnode_handle(sub_node),  in aat1290_led_probe()
506 	if (IS_ERR(led->v4l2_flash)) {  in aat1290_led_probe()
507 		ret = PTR_ERR(led->v4l2_flash);  in aat1290_led_probe()
516 	mutex_destroy(&led->lock);  in aat1290_led_probe()
523 	struct aat1290_led *led = platform_get_drvdata(pdev);  in aat1290_led_remove()  local
525 	v4l2_flash_release(led->v4l2_flash);  in aat1290_led_remove()
526 	led_classdev_flash_unregister(&led->fled_cdev);  in aat1290_led_remove()
528 	mutex_destroy(&led->lock);  in aat1290_led_remove()
549 MODULE_DESCRIPTION("Skyworks Current Regulator for Flash LEDs");