From nobody Wed Apr 1 09:45:44 2026 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 EEA0E30DEDC; Tue, 31 Mar 2026 17:08:08 +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=1774976889; cv=none; b=JuX/EwjHqjwf9e614Uogn9H/hb77zrXqnbdsvc8m24oIwkP3idQ2JTgwEpspFVV4eMtH61nu6JHGS5HcL6aetjlmBbVvXseYm5jQKoJKn8uYECrX6q+vnHZdtSyeTH6/pDd+h1fW0PSYdfguYSYbSRqTVozGlZoz08jfOq2xvVA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774976889; c=relaxed/simple; bh=1ilQ6NwIUAHuE2aXouCYG3EJCP4y8gHjjw4b67QEdUk=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=ilIybP6wMONjYJSvIfhF7b8IylM/11DsQdWFjAHOEEYPfWnZo/LeOJkW2xXGTaenIXh12hUIq6h3EJyEQzFWA2RvUU5yyoW3EgTpO1IslcR4slcxWlUQIBpBzZEAnpRBKmuhdeb39rYW2gvqWRp0z8IREv5UtSEzH+WUj2y8zwM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=ihxkAxSo; 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="ihxkAxSo" Received: by smtp.kernel.org (Postfix) with ESMTPS id BB4C2C2BCB7; Tue, 31 Mar 2026 17:08:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774976888; bh=1ilQ6NwIUAHuE2aXouCYG3EJCP4y8gHjjw4b67QEdUk=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=ihxkAxSoKYhMGXu3BnFe9EbNduu71ZjjQ0s+JMS8OAFmw3nZIw0AFh8C/LHT5bccE hvAc7vopHE7zpdOEZNZ3jAR6W35Mv2PoBTWH6tsuLCVEwAXOPIJr6PjE9Urd1c+vXR dT+pjrABYohYeVBM5IYzusPKxdS13kVeW7ingeejGSm5lCL530ZNKe4RqY7wMx0c+Y YN2HGDRs6aOVLKen2I7d0gTW2DlBw8UjhrvPVG6uFW+sjdlbXrsiNVCUn6Kt/oyxKf e/yG9flkrrpTesiB1DZuRpVUHTIdCCqMZhzKN89LLE1R4lCP4JnBpXJnGorjFXtV4e HjxYN+V5XfzLQ== 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 AE34910F92EB; Tue, 31 Mar 2026 17:08:08 +0000 (UTC) From: Rudraksha Gupta via B4 Relay Date: Tue, 31 Mar 2026 10:08:08 -0700 Subject: [PATCH v4 2/3] leds: flash: rt8515: Support single-GPIO flash ICs with vin supply Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <20260331-expressatt_camera_flash-v4-2-f1e99f474513@gmail.com> References: <20260331-expressatt_camera_flash-v4-0-f1e99f474513@gmail.com> In-Reply-To: <20260331-expressatt_camera_flash-v4-0-f1e99f474513@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=1774976888; l=6626; i=guptarud@gmail.com; s=20240916; h=from:subject:message-id; bh=zZMrBj64Vyzjy9VmRNEhdaRoz7QyR5FMwlozpltanIw=; b=HmrcrSMHPZJNXzn2ONNfC4cfqhJNThuubjSJxk2wAFZA36qAzISrc/thEDUdcCtHIWAVCANvl a26on99UkSeBL/pA90C6DsjINzXLPUndo/9GTq4l9uSIvpY1sjWdd7y 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 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 Reviewed-by: Linus Walleij --- drivers/leds/flash/leds-rt8515.c | 100 ++++++++++++++++++++++++++++++++---= ---- 1 file changed, 83 insertions(+), 17 deletions(-) diff --git a/drivers/leds/flash/leds-rt8515.c b/drivers/leds/flash/leds-rt8= 515.c index f6b439674c03..c7f0bdf804a7 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_fla= sh *fled) return container_of(fled, struct rt8515, fled); } =20 -static void rt8515_gpio_led_off(struct rt8515 *rt) +static int rt8515_gpio_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 =3D regulator_is_enabled(rt->reg); + if (ret < 0) + return ret; + if (ret > 0) + return regulator_disable(rt->reg); + + return 0; } =20 -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 =3D rt8515_gpio_led_off(rt); + if (ret) + return ret; + /* IC needs time to reset its brightness counter */ + usleep_range(100, 200); + /* Enable regulator */ + ret =3D regulator_enable(rt->reg); + if (ret) + return ret; =20 /* * Toggling a GPIO line with a small delay increases the @@ -84,6 +112,8 @@ static void rt8515_gpio_brightness_commit(struct gpio_de= sc *gpiod, gpiod_set_value(gpiod, 1); udelay(1); } + + return 0; } =20 /* This is setting the torch light level */ @@ -92,23 +122,39 @@ static int rt8515_led_brightness_set(struct led_classd= ev *led, { struct led_classdev_flash *fled =3D lcdev_to_flcdev(led); struct rt8515 *rt =3D to_rt8515(fled); + int ret =3D 0; =20 mutex_lock(&rt->lock); =20 if (brightness =3D=3D LED_OFF) { /* Off */ - rt8515_gpio_led_off(rt); + ret =3D 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 =3D rt8515_gpio_brightness_commit(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); + /* + * 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_torch : + rt->enable_flash, 1); } =20 +out: mutex_unlock(&rt->lock); =20 - return 0; + return ret; } =20 static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, @@ -117,27 +163,33 @@ static int rt8515_led_flash_strobe_set(struct led_cla= ssdev_flash *fled, struct rt8515 *rt =3D to_rt8515(fled); struct led_flash_setting *timeout =3D &fled->timeout; int brightness =3D rt->flash_max_intensity; + int ret =3D 0; =20 mutex_lock(&rt->lock); =20 if (state) { /* Enable LED flash mode and set brightness */ - rt8515_gpio_brightness_commit(rt->enable_flash, brightness); + ret =3D rt8515_gpio_brightness_commit(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 =3D rt8515_gpio_led_off(rt); + if (ret) + goto out; } =20 fled->led_cdev.brightness =3D LED_OFF; /* After this the torch LED will be disabled */ =20 +out: mutex_unlock(&rt->lock); =20 - return 0; + return ret; } =20 static int rt8515_led_flash_strobe_get(struct led_classdev_flash *fled, @@ -166,9 +218,12 @@ static const struct led_flash_ops rt8515_flash_ops =3D= { static void rt8515_powerdown_timer(struct timer_list *t) { struct rt8515 *rt =3D timer_container_of(rt, t, powerdown_timer); + int ret; =20 /* Turn the LED off */ - rt8515_gpio_led_off(rt); + ret =3D rt8515_gpio_led_off(rt); + if (ret) + dev_err(rt->dev, "failed to turn off LED (%d)\n", ret); } =20 static void rt8515_init_flash_timeout(struct rt8515 *rt) @@ -298,12 +353,18 @@ 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"); =20 - /* ENT - Enable Torch line */ - rt->enable_torch =3D devm_gpiod_get(dev, "ent", GPIOD_OUT_LOW); + /* ENT - Enable Torch line (optional for single-GPIO flash ICs) */ + rt->enable_torch =3D 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"); =20 + /* Optional VIN supply */ + rt->reg =3D 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 =3D device_get_next_child_node(dev, NULL); if (!child) { dev_err(dev, @@ -333,7 +394,12 @@ static int rt8515_probe(struct platform_device *pdev) =20 fled->ops =3D &rt8515_flash_ops; =20 - led->max_brightness =3D rt->torch_max_intensity; + /* + * If there is no separate torch pin, use the flash max intensity + * as the max brightness instead. + */ + led->max_brightness =3D rt->enable_torch ? + rt->torch_max_intensity : rt->flash_max_intensity; led->brightness_set_blocking =3D rt8515_led_brightness_set; led->flags |=3D LED_CORE_SUSPENDRESUME | LED_DEV_CAP_FLASH; =20 --=20 2.53.0