media: atomisp: gc0310: Power on sensor from set_fmt() callback

Depending on which order userspace makes various v4l2 calls, the sensor
might still be powered down when set_fmt is called.

What should really happen here is delay the writing of the mode-related
registers till streaming is started, but for now use the same quick fix
as the atomisp_ov2680 code and call power_up() from set_fmt() in
combination with keeping track of the power-state to avoid doing the
power-up sequence twice.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

drivers/staging/media/atomisp/i2c/atomisp-gc0310.c

@@ -786,8 +786,6 @@ static int gpio_ctrl(struct v4l2_subdev *sd, bool flag)
 	return ret;
 }
 
-static int power_down(struct v4l2_subdev *sd);
-
 static int power_up(struct v4l2_subdev *sd)
 {
 	struct gc0310_device *dev = to_gc0310_sensor(sd);
@@ -800,6 +798,9 @@ static int power_up(struct v4l2_subdev *sd)
 		return -ENODEV;
 	}
 
+	if (dev->power_on)
+		return 0; /* Already on */
+
 	/* power control */
 	ret = power_ctrl(sd, 1);
 	if (ret)
@@ -820,6 +821,7 @@ static int power_up(struct v4l2_subdev *sd)
 
 	msleep(100);
 
+	dev->power_on = true;
 	return 0;
 
 fail_gpio:
@@ -844,6 +846,9 @@ static int power_down(struct v4l2_subdev *sd)
 		return -ENODEV;
 	}
 
+	if (!dev->power_on)
+		return 0; /* Already off */
+
 	/* gpio ctrl */
 	ret = gpio_ctrl(sd, 0);
 	if (ret) {
@@ -861,6 +866,7 @@ static int power_down(struct v4l2_subdev *sd)
 	if (ret)
 		dev_err(&client->dev, "vprog failed.\n");
 
+	dev->power_on = false;
 	return ret;
 }
 
@@ -935,6 +941,9 @@ static int gc0310_set_fmt(struct v4l2_subdev *sd,
 		return 0;
 	}
 
+	/* s_power has not been called yet for std v4l2 clients (camorama) */
+	power_up(sd);
+
 	dev_dbg(&client->dev, "%s: before gc0310_write_reg_array %s\n",
 		__func__, dev->res->desc);
 	ret = startup(sd);
@@ -1073,6 +1082,7 @@ static int gc0310_s_config(struct v4l2_subdev *sd,
 	 * as first power on by board may not fulfill the
 	 * power on sequqence needed by the module
 	 */
+	dev->power_on = true; /* force power_down() to run */
 	ret = power_down(sd);
 	if (ret) {
 		dev_err(&client->dev, "gc0310 power-off err.\n");

drivers/staging/media/atomisp/i2c/gc0310.h

@@ -152,6 +152,7 @@ struct gc0310_device {
 	int vt_pix_clk_freq_mhz;
 	struct gc0310_resolution *res;
 	u8 type;
+	bool power_on;
 };
 
 enum gc0310_tok_type {