From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 815193438AF; Thu, 28 May 2026 02:34:32 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779935672; cv=none; b=JzuczlF6l5U4Zm38VDLXRX52KKbQ/SbXRivXLHlLa7xtVh3dyQVeqgjAZoyNBeBp69d8MdEcj3RbixPK0P5x4HDooppJPB28Kpeah2UkTxtHtlQXvtNUtgwqO5P4dK3oe9lV55Og1CabDVdMMS6FQM5pqsCmoioU7XZmA/da7TY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1779935672; c=relaxed/simple; bh=Y+4wVy0zYARcOMHewWAaadofMeQq0fIFyZ0TGq0ZCY8=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=h68SJzW1dsLE8NkZqZJF6oSPSX3AZCrytyzAunZaJRg8LRHadiEDjhxfBhg+27Yuivl2iPzT9s2BjwajM/ztEP+NzWtiuREAbmD+Gqh9h8GxjJxNzCJPMGtdLBYoY6VIkhdpzihLofJUY+41r2K2oFtk2BRk9MW4Nd1qYgbBg9c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mDFDcqHI; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mDFDcqHI" Received: by smtp.kernel.org (Postfix) with ESMTPS id 37C3DC2BCC7; Thu, 28 May 2026 02:34:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1779935672; bh=Y+4wVy0zYARcOMHewWAaadofMeQq0fIFyZ0TGq0ZCY8=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=mDFDcqHI/hEBhKlpKPoiBW6wViuW8n5xRm/ZIZeVvU4eBJcrsPqPL8Ei2f7GLG/4P U67E3gfvwp5/USnEcSb3A8ULN939BfgR9yMdqW2rx+w68CoxOZTzDIRIowRpXFWFk2 9G2rE6rCX9X/cdsr0B2zoDFO4NjqrKmaYVBuo1OdDZtlmINX2C7N4OK2gFzMTh9iwA CvFNggSzO2kje1ZqVE5FJJLwT7BmnjDOHHxnZyBk0lAbb92v4adGHUpHPIBAeCTDY3 K7+aE7pwNVyLZcRaPQc7v1uisT6J7vkEKs0SGidMu2Zh+eTd382IJKM/nE7E//dWP+ qRqqPMpTKMjzw== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23B40CD5BC9; Thu, 28 May 2026 02:34:32 +0000 (UTC) From: Rudraksha Gupta via B4 Relay Date: Wed, 27 May 2026 19:34:31 -0700 Subject: [PATCH v6 2/3] leds: flash: rt8515: Support single-GPIO flash ICs with vin supply Precedence: bulk X-Mailing-List: linux-leds@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260527-expressatt_camera_flash-v6-2-de0f150024e4@gmail.com> References: <20260527-expressatt_camera_flash-v6-0-de0f150024e4@gmail.com> In-Reply-To: <20260527-expressatt_camera_flash-v6-0-de0f150024e4@gmail.com> To: Lee Jones , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Linus Walleij , Bjorn Andersson , Konrad Dybcio , Liam Girdwood , Mark Brown Cc: linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, phone-devel@vger.kernel.org, Rudraksha Gupta X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1779935671; l=8840; i=guptarud@gmail.com; s=20240916; h=from:subject:message-id; bh=ECsUFWhTz2Rp4ynQ93GJ/pcNMjhSeYMsU+5K5mwgLYA=; b=E84r0jz3m/L680wFgNeCdunrTp+3koZAjcqJHxPV5OrepgPKzNhhMIB2klC9prQnRppxiqM4p dwM7B/PKPMQBqk1Gvnu8mFSUNjEHIS8vj0EKqklZHCCZt7c346v0GHC X-Developer-Key: i=guptarud@gmail.com; a=ed25519; pk=ETrudRugWAtOpr0OhRiheQ1lXM4Kk4KGFnBySlKDi2I= X-Endpoint-Received: by B4 Relay for guptarud@gmail.com/20240916 with auth_id=211 X-Original-From: Rudraksha Gupta Reply-To: guptarud@gmail.com From: Rudraksha Gupta 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. When ent-gpios is absent, the driver uses enf-gpios for both flash and torch brightness control. Assisted-by: Claude:claude-opus-4.6 Reviewed-by: Linus Walleij Signed-off-by: Rudraksha Gupta --- drivers/leds/flash/leds-rt8515.c | 148 +++++++++++++++++++++++++++++---------- 1 file changed, 112 insertions(+), 36 deletions(-) diff --git a/drivers/leds/flash/leds-rt8515.c b/drivers/leds/flash/leds-rt8515.c index f6b439674c03..0fb84d98211d 100644 --- a/drivers/leds/flash/leds-rt8515.c +++ b/drivers/leds/flash/leds-rt8515.c @@ -31,6 +31,7 @@ #include #include #include +#include #include @@ -44,6 +45,9 @@ #define RT8515_TIMEOUT_US 250000U #define RT8515_MAX_TIMEOUT_US 300000U +#define RT8515_OFF 0 +#define RT8515_ON 1 + struct rt8515 { struct led_classdev_flash fled; struct device *dev; @@ -52,7 +56,7 @@ struct rt8515 { struct regulator *reg; struct gpio_desc *enable_torch; struct gpio_desc *enable_flash; - struct timer_list powerdown_timer; + struct delayed_work powerdown_work; u32 max_timeout; /* Flash max timeout */ int flash_max_intensity; int torch_max_intensity; @@ -63,27 +67,57 @@ 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_gpio_led_off(struct rt8515 *rt) { - gpiod_set_value(rt->enable_flash, 0); - gpiod_set_value(rt->enable_torch, 0); + int ret = 0; + + gpiod_set_value(rt->enable_flash, RT8515_OFF); + gpiod_set_value(rt->enable_torch, RT8515_OFF); + + if (!rt->reg) + return ret; + + ret = regulator_is_enabled(rt->reg); + if (ret > 0) + ret = regulator_disable(rt->reg); + + return ret; } -static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod, - int brightness) +static int rt8515_gpio_brightness_commit(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_gpio_led_off(rt); + if (ret) + return ret; + + /* IC needs time to reset its brightness counter */ + usleep_range(100, 200); + + if (rt->reg) { + ret = regulator_enable(rt->reg); + if (ret) + return ret; + } /* * Toggling a GPIO line with a small delay increases the * brightness one step at a time. */ for (i = 0; i < brightness; i++) { - gpiod_set_value(gpiod, 0); + gpiod_set_value(gpiod, RT8515_OFF); udelay(1); - gpiod_set_value(gpiod, 1); + gpiod_set_value(gpiod, RT8515_ON); udelay(1); } + + return 0; } /* This is setting the torch light level */ @@ -92,23 +126,38 @@ static int rt8515_led_brightness_set(struct led_classdev *led, { 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_gpio_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. + * If there is no separate torch pin, use the flash pin + * for torch as well. + */ + ret = rt8515_gpio_brightness_commit(rt, + rt->enable_torch ?: rt->enable_flash, brightness); + if (ret) + goto out; } else { - /* Max torch brightness requested */ - gpiod_set_value(rt->enable_torch, 1); + /* + * Max torch brightness requested. + * If there is no separate torch pin, use the flash pin + * for torch as well. + */ + gpiod_set_value(rt->enable_torch ?: rt->enable_flash, RT8515_ON); } +out: mutex_unlock(&rt->lock); - return 0; + return ret; } static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, @@ -117,27 +166,36 @@ 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); - /* Set timeout */ - mod_timer(&rt->powerdown_timer, - jiffies + usecs_to_jiffies(timeout->val)); - } else { - timer_delete_sync(&rt->powerdown_timer); + if (!state) { + cancel_delayed_work_sync(&rt->powerdown_work); + mutex_lock(&rt->lock); /* Turn the LED off */ - rt8515_gpio_led_off(rt); + ret = rt8515_gpio_led_off(rt); + if (!ret) + fled->led_cdev.brightness = LED_OFF; + mutex_unlock(&rt->lock); + return ret; } + mutex_lock(&rt->lock); + + /* Enable LED flash mode and set brightness */ + ret = rt8515_gpio_brightness_commit(rt, rt->enable_flash, brightness); + if (ret) + goto out; + + /* Set timeout */ + schedule_delayed_work(&rt->powerdown_work, usecs_to_jiffies(timeout->val)); + 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, @@ -145,7 +203,7 @@ static int rt8515_led_flash_strobe_get(struct led_classdev_flash *fled, { struct rt8515 *rt = to_rt8515(fled); - *state = timer_pending(&rt->powerdown_timer); + *state = delayed_work_pending(&rt->powerdown_work); return 0; } @@ -163,12 +221,18 @@ static const struct led_flash_ops rt8515_flash_ops = { .timeout_set = rt8515_led_flash_timeout_set, }; -static void rt8515_powerdown_timer(struct timer_list *t) +static void rt8515_powerdown_work(struct work_struct *work) { - struct rt8515 *rt = timer_container_of(rt, t, powerdown_timer); + struct rt8515 *rt = container_of(work, struct rt8515, powerdown_work.work); + int ret; /* Turn the LED off */ - rt8515_gpio_led_off(rt); + mutex_lock(&rt->lock); + ret = rt8515_gpio_led_off(rt); + mutex_unlock(&rt->lock); + + if (ret) + dev_err(rt->dev, "failed to turn off LED (%d)\n", ret); } static void rt8515_init_flash_timeout(struct rt8515 *rt) @@ -298,11 +362,18 @@ 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"); + "Failed to obtain the Enable Torch GPIO\n"); + + rt->reg = devm_regulator_get_optional(dev, "vin"); + if (IS_ERR(rt->reg)) { + if (PTR_ERR(rt->reg) == -EPROBE_DEFER) + return -EPROBE_DEFER; + rt->reg = NULL; + } child = device_get_next_child_node(dev, NULL); if (!child) { @@ -328,12 +399,17 @@ static int rt8515_probe(struct platform_device *pdev) dev_warn(dev, "flash-max-timeout-us property missing\n"); } - timer_setup(&rt->powerdown_timer, rt8515_powerdown_timer, 0); + INIT_DELAYED_WORK(&rt->powerdown_work, rt8515_powerdown_work); rt8515_init_flash_timeout(rt); fled->ops = &rt8515_flash_ops; - led->max_brightness = rt->torch_max_intensity; + /* + * If there is no separate torch pin, use flash max intensity + * as max brightness instead. + */ + led->max_brightness = rt->enable_torch ? + rt->torch_max_intensity : rt->flash_max_intensity; led->brightness_set_blocking = rt8515_led_brightness_set; led->flags |= LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH; @@ -372,7 +448,7 @@ static void rt8515_remove(struct platform_device *pdev) struct rt8515 *rt = platform_get_drvdata(pdev); rt8515_v4l2_flash_release(rt); - timer_delete_sync(&rt->powerdown_timer); + cancel_delayed_work_sync(&rt->powerdown_work); mutex_destroy(&rt->lock); } -- 2.54.0