From: Rudraksha Gupta Date: Fri, 06 Mar 2026 16:58:03 -0800 Subject: [PATCH 2/3] leds: flash: rt8515: Support single-GPIO flash ICs with unlock gate MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260306-expressatt_camera_flash-v1-2-b1996f7cdfdd@gmail.com> References: <20260306-expressatt_camera_flash-v1-0-b1996f7cdfdd@gmail.com> In-Reply-To: <20260306-expressatt_camera_flash-v1-0-b1996f7cdfdd@gmail.com> To: Lee Jones , Pavel Machek , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Linus Walleij , Bjorn Andersson , Konrad Dybcio Cc: linux-leds@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, Rudraksha Gupta X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1772845083; l=3781; i=guptarud@gmail.com; s=20240916; h=from:subject:message-id; bh=eBn8zK2zm3rDt5Cq7ivsaMjK/w9HVVqK9pNgZvC1x40=; b=UGnv+rPdrIkDsaPCfH0UYYPewggp5aHqP1G8iGvesY+NLY+lLUq1qPqga3ovVhzNgVzx5sl0w SGvmYjjv2mDCarGK2PGGbQNJeXJUO0bubloizi0gW2DiVMpf0Oq6bHu 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 List-Id: B4 Relay Submissions 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 unlock GPIO that gates the flash circuit. Signed-off-by: Rudraksha Gupta --- drivers/leds/flash/leds-rt8515.c | 38 ++++++++++++++++++++++++++++++++------ 1 file changed, 32 insertions(+), 6 deletions(-) diff --git a/drivers/leds/flash/leds-rt8515.c b/drivers/leds/flash/leds-rt8515.c index f6b439674c03..3164bf91e4c9 100644 --- a/drivers/leds/flash/leds-rt8515.c +++ b/drivers/leds/flash/leds-rt8515.c @@ -52,6 +52,7 @@ struct rt8515 { struct regulator *reg; struct gpio_desc *enable_torch; struct gpio_desc *enable_flash; + struct gpio_desc *unlock_gpio; struct timer_list powerdown_timer; u32 max_timeout; /* Flash max timeout */ int flash_max_intensity; @@ -66,7 +67,10 @@ static struct rt8515 *to_rt8515(struct led_classdev_flash *fled) static void rt8515_gpio_led_off(struct rt8515 *rt) { 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); + if (rt->unlock_gpio) + gpiod_set_value_cansleep(rt->unlock_gpio, 0); } static void rt8515_gpio_brightness_commit(struct gpio_desc *gpiod, @@ -99,11 +103,19 @@ static int rt8515_led_brightness_set(struct led_classdev *led, /* Off */ rt8515_gpio_led_off(rt); } 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); + /* Unlock the flash circuit if needed */ + if (rt->unlock_gpio) + gpiod_set_value_cansleep(rt->unlock_gpio, 1); + /* Step it up to movie mode brightness */ + rt8515_gpio_brightness_commit(rt->enable_torch ? + rt->enable_torch : rt->enable_flash, brightness); } else { + /* Unlock the flash circuit if needed */ + if (rt->unlock_gpio) + gpiod_set_value_cansleep(rt->unlock_gpio, 1); /* Max torch brightness requested */ - gpiod_set_value(rt->enable_torch, 1); + gpiod_set_value(rt->enable_torch ? rt->enable_torch : + rt->enable_flash, 1); } mutex_unlock(&rt->lock); @@ -121,6 +133,9 @@ static int rt8515_led_flash_strobe_set(struct led_classdev_flash *fled, mutex_lock(&rt->lock); if (state) { + /* Unlock the flash circuit if needed */ + if (rt->unlock_gpio) + gpiod_set_value_cansleep(rt->unlock_gpio, 1); /* Enable LED flash mode and set brightness */ rt8515_gpio_brightness_commit(rt->enable_flash, brightness); /* Set timeout */ @@ -298,12 +313,23 @@ 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 unlock GPIO (e.g. PMIC MPP to gate flash circuit) */ + rt->unlock_gpio = devm_gpiod_get_optional(dev, "unlock", GPIOD_OUT_LOW); + if (IS_ERR(rt->unlock_gpio)) + return dev_err_probe(dev, PTR_ERR(rt->unlock_gpio), + "cannot get unlock GPIO\n"); + + /* Exactly one of ENT or unlock must be provided */ + if (!rt->enable_torch == !rt->unlock_gpio) + return dev_err_probe(dev, -EINVAL, + "exactly one of ent-gpios or unlock-gpios is required\n"); + child = device_get_next_child_node(dev, NULL); if (!child) { dev_err(dev, -- 2.53.0