linux-kernel - [PATCH 3/3] media: dw9714: add support for powerdown pin

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Message-Id: <20250612-dw9714-v1-3-1a2d6d682829@emfend.at>
Date: Thu, 12 Jun 2025 08:54:12 +0200
From: Matthias Fend <matthias.fend@...end.at>
To: Sakari Ailus <sakari.ailus@...ux.intel.com>, 
 Mauro Carvalho Chehab <mchehab@...nel.org>
Cc: linux-media@...r.kernel.org, linux-kernel@...r.kernel.org, 
 Matthias Fend <matthias.fend@...end.at>, 
 bsp-development.geo@...ca-geosystems.com
Subject: [PATCH 3/3] media: dw9714: add support for powerdown pin

Add support for the powerdown pin (xSD), which can be used to put the VCM
driver into power down mode. This is useful, for example, if the VCM
driver's power supply cannot be controlled. The use of the powerdown pin is
optional.

Signed-off-by: Matthias Fend <matthias.fend@...end.at>
---
 drivers/media/i2c/Kconfig  |  2 +-
 drivers/media/i2c/dw9714.c | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index e45ba127069fc0848f1a06ceb789efd3c222c008..e923daeec9c574c5b8c7014b9e83fcbad47866c0 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -748,7 +748,7 @@ config VIDEO_AK7375
 
 config VIDEO_DW9714
 	tristate "DW9714 lens voice coil support"
-	depends on I2C && VIDEO_DEV
+	depends on GPIOLIB && I2C && VIDEO_DEV
 	select MEDIA_CONTROLLER
 	select VIDEO_V4L2_SUBDEV_API
 	select V4L2_ASYNC
diff --git a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c
index 2abd4fb5e7c0f02ab96bf8fa5f557941187920a3..1e7ad355a388cfc37253bd764ec8df98f59beeea 100644
--- a/drivers/media/i2c/dw9714.c
+++ b/drivers/media/i2c/dw9714.c
@@ -2,6 +2,7 @@
 // Copyright (c) 2015--2017 Intel Corporation.
 
 #include <linux/delay.h>
+#include <linux/gpio/consumer.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
@@ -38,6 +39,7 @@ struct dw9714_device {
 	struct v4l2_subdev sd;
 	u16 current_val;
 	struct regulator *vcc;
+	struct gpio_desc *powerdown_gpio;
 };
 
 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
@@ -145,6 +147,8 @@ static int dw9714_power_up(struct dw9714_device *dw9714_dev)
 	if (ret)
 		return ret;
 
+	gpiod_set_value_cansleep(dw9714_dev->powerdown_gpio, 0);
+
 	usleep_range(1000, 2000);
 
 	return 0;
@@ -152,6 +156,8 @@ static int dw9714_power_up(struct dw9714_device *dw9714_dev)
 
 static int dw9714_power_down(struct dw9714_device *dw9714_dev)
 {
+	gpiod_set_value_cansleep(dw9714_dev->powerdown_gpio, 1);
+
 	return regulator_disable(dw9714_dev->vcc);
 }
 
@@ -169,6 +175,14 @@ static int dw9714_probe(struct i2c_client *client)
 	if (IS_ERR(dw9714_dev->vcc))
 		return PTR_ERR(dw9714_dev->vcc);
 
+	dw9714_dev->powerdown_gpio = devm_gpiod_get_optional(&client->dev,
+							     "powerdown",
+							     GPIOD_OUT_HIGH);
+	if (IS_ERR(dw9714_dev->powerdown_gpio))
+		return dev_err_probe(&client->dev,
+				     PTR_ERR(dw9714_dev->powerdown_gpio),
+				     "could not get powerdown gpio\n");
+
 	rval = dw9714_power_up(dw9714_dev);
 	if (rval)
 		return dev_err_probe(&client->dev, rval,

-- 
2.34.1