From: Rudraksha Gupta <[email protected]> Extend the RT8515 driver to support flash ICs that use only a single GPIO for both flash and torch modes (no separate ENT pin), with an optional vin regulator that gates power to the flash IC.
When vin-supply is provided, the driver enables the regulator before activating the LED and disables it when turning off. Make ent-gpios optional and validate at probe time that exactly one of ent-gpios or vin-supply is provided. When ent-gpios is absent, the driver uses enf-gpios for both flash and torch brightness control. Assisted-by: Claude:claude-opus-4.6 Signed-off-by: Rudraksha Gupta <[email protected]> --- drivers/leds/flash/leds-rt8515.c | 90 ++++++++++++++++++++++++++++++++-------- 1 file changed, 72 insertions(+), 18 deletions(-) diff --git a/drivers/leds/flash/leds-rt8515.c b/drivers/leds/flash/leds-rt8515.c index f6b439674c03..739cac8789c8 100644 --- a/drivers/leds/flash/leds-rt8515.c +++ b/drivers/leds/flash/leds-rt8515.c @@ -63,16 +63,44 @@ static struct rt8515 *to_rt8515(struct led_classdev_flash *fled) return container_of(fled, struct rt8515, fled); } -static void rt8515_gpio_led_off(struct rt8515 *rt) +static int rt8515_led_off(struct rt8515 *rt) { + int ret; + gpiod_set_value(rt->enable_flash, 0); - gpiod_set_value(rt->enable_torch, 0); + if (rt->enable_torch) + gpiod_set_value(rt->enable_torch, 0); + + /* Disable regulator */ + ret = regulator_is_enabled(rt->reg); + if (ret < 0) + return ret; + if (ret > 0) + return regulator_disable(rt->reg); + + return 0; } -static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod, - int brightness) +static int rt8515_set_flash_brightness(struct rt8515 *rt, + struct gpio_desc *gpiod, + int brightness) { int i; + int ret; + + /* + * Reset the IC to start brightness from zero, + * then re-enable and pulse to the desired level. + */ + ret = rt8515_led_off(rt); + if (ret) + return ret; + /* IC needs time to reset its brightness counter */ + usleep_range(100, 200); + /* Enable regulator */ + ret = regulator_enable(rt->reg); + if (ret) + return ret; /* * Toggling a GPIO line with a small delay increases the @@ -84,31 +112,41 @@ static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod, gpiod_set_value(gpiod, 1); udelay(1); } + + return 0; } /* This is setting the torch light level */ -static int rt8515_led_brightness_set(struct led_classdev *led, +static int rt8515_set_brightness(struct led_classdev *led, enum led_brightness brightness) { struct led_classdev_flash *fled = lcdev_to_flcdev(led); struct rt8515 *rt = to_rt8515(fled); + int ret = 0; mutex_lock(&rt->lock); if (brightness == LED_OFF) { /* Off */ - rt8515_gpio_led_off(rt); + ret = rt8515_led_off(rt); + if (ret) + goto out; } else if (brightness < RT8515_TORCH_MAX) { - /* Step it up to movie mode brightness using the flash pin */ - rt8515_gpio_brightness_commit(rt->enable_torch, brightness); + /* Step it up to movie mode brightness */ + ret = rt8515_set_flash_brightness(rt, rt->enable_torch ? + rt->enable_torch : rt->enable_flash, brightness); + if (ret) + goto out; } else { /* Max torch brightness requested */ - gpiod_set_value(rt->enable_torch, 1); + gpiod_set_value(rt->enable_torch ? rt->enable_torch : + rt->enable_flash, 1); } +out: mutex_unlock(&rt->lock); - return 0; + return ret; } static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, @@ -117,27 +155,33 @@ static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, struct rt8515 *rt = to_rt8515(fled); struct led_flash_setting *timeout = &fled->timeout; int brightness = rt->flash_max_intensity; + int ret = 0; mutex_lock(&rt->lock); if (state) { /* Enable LED flash mode and set brightness */ - rt8515_gpio_brightness_commit(rt->enable_flash, brightness); + ret = rt8515_set_flash_brightness(rt, rt->enable_flash, brightness); + if (ret) + goto out; /* Set timeout */ mod_timer(&rt->powerdown_timer, jiffies + usecs_to_jiffies(timeout->val)); } else { timer_delete_sync(&rt->powerdown_timer); /* Turn the LED off */ - rt8515_gpio_led_off(rt); + ret = rt8515_led_off(rt); + if (ret) + goto out; } fled->led_cdev.brightness = LED_OFF; /* After this the torch LED will be disabled */ +out: mutex_unlock(&rt->lock); - return 0; + return ret; } static int rt8515_led_flash_strobe_get(struct led_classdev_flash *fled, @@ -166,9 +210,12 @@ static const struct led_flash_ops rt8515_flash_ops = { static void rt8515_powerdown_timer(struct timer_list *t) { struct rt8515 *rt = timer_container_of(rt, t, powerdown_timer); + int ret; /* Turn the LED off */ - rt8515_gpio_led_off(rt); + ret = rt8515_led_off(rt); + if (ret) + dev_err(rt->dev, "failed to turn off LED (%d)\n", ret); } static void rt8515_init_flash_timeout(struct rt8515 *rt) @@ -298,12 +345,18 @@ static int rt8515_probe(struct platform_device *pdev) return dev_err_probe(dev, PTR_ERR(rt->enable_flash), "cannot get ENF (enable flash) GPIO\n"); - /* ENT - Enable Torch line */ - rt->enable_torch = devm_gpiod_get(dev, "ent", GPIOD_OUT_LOW); + /* ENT - Enable Torch line (optional for single-GPIO flash ICs) */ + rt->enable_torch = devm_gpiod_get_optional(dev, "ent", GPIOD_OUT_LOW); if (IS_ERR(rt->enable_torch)) return dev_err_probe(dev, PTR_ERR(rt->enable_torch), "cannot get ENT (enable torch) GPIO\n"); + /* Optional VIN supply */ + rt->reg = devm_regulator_get(dev, "vin"); + if (IS_ERR(rt->reg)) + return dev_err_probe(dev, PTR_ERR(rt->reg), + "failed to get vin supply\n"); + child = device_get_next_child_node(dev, NULL); if (!child) { dev_err(dev, @@ -333,8 +386,9 @@ static int rt8515_probe(struct platform_device *pdev) fled->ops = &rt8515_flash_ops; - led->max_brightness = rt->torch_max_intensity; - led->brightness_set_blocking = rt8515_led_brightness_set; + led->max_brightness = rt->enable_torch ? + rt->torch_max_intensity : rt->flash_max_intensity; + led->brightness_set_blocking = rt8515_set_brightness; led->flags |= LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH; mutex_init(&rt->lock); -- 2.53.0
