From: Ondrej Jirman <megous@megous.com>
Date: Fri, 22 Oct 2021 21:44:13 +0200
Subject: [PATCH 22/36] media: i2c: imx258: Add support for reset gpio

It was documented in DT, but not implemented.

Signed-off-by: Ondrej Jirman <megous@megous.com>
---
 drivers/media/i2c/imx258.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/media/i2c/imx258.c b/drivers/media/i2c/imx258.c
index e64fadc..ec6e919 100644
--- a/drivers/media/i2c/imx258.c
+++ b/drivers/media/i2c/imx258.c
@@ -615,6 +615,7 @@ struct imx258 {
 	struct v4l2_ctrl *exposure;
 
 	struct gpio_desc *pwdn_gpio;
+	struct gpio_desc *reset_gpio;
 
 	/* Current mode */
 	const struct imx258_mode *cur_mode;
@@ -1020,7 +1021,11 @@ static int imx258_power_on(struct device *dev)
 	if (ret)
 		dev_err(dev, "failed to enable clock\n");
 
-	return ret;
+	gpiod_set_value_cansleep(imx258->reset_gpio, 0);
+
+	usleep_range(400, 500);
+
+	return 0;
 }
 
 static int imx258_power_off(struct device *dev)
@@ -1030,6 +1035,7 @@ static int imx258_power_off(struct device *dev)
 
 	clk_disable_unprepare(imx258->clk);
 
+	gpiod_set_value_cansleep(imx258->reset_gpio, 1);
 	gpiod_set_value_cansleep(imx258->pwdn_gpio, 1);
 
 	return 0;
@@ -1301,6 +1307,12 @@ static int imx258_probe(struct i2c_client *client)
 	if (IS_ERR(imx258->pwdn_gpio))
 		return PTR_ERR(imx258->pwdn_gpio);
 
+	/* request optional reset pin */
+	imx258->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset",
+						    GPIOD_OUT_HIGH);
+	if (IS_ERR(imx258->reset_gpio))
+		return PTR_ERR(imx258->reset_gpio);
+
 	/* Initialize subdev */
 	v4l2_i2c_subdev_init(&imx258->sd, client, &imx258_subdev_ops);