media: atomisp: ov2722: 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 / atomisp_gc0310 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-ov2722.c

@@ -528,6 +528,9 @@ static int power_up(struct v4l2_subdev *sd)
 		return -ENODEV;
 	}
 
+	if (dev->power_on == 1)
+		return 0; /* Already on */
+
 	/* power control */
 	ret = power_ctrl(sd, 1);
 	if (ret)
@@ -552,6 +555,7 @@ static int power_up(struct v4l2_subdev *sd)
 	/* according to DS, 20ms is needed between PWDN and i2c access */
 	msleep(20);
 
+	dev->power_on = 1;
 	return 0;
 
 fail_clk:
@@ -575,6 +579,9 @@ static int power_down(struct v4l2_subdev *sd)
 		return -ENODEV;
 	}
 
+	if (dev->power_on == 0)
+		return 0; /* Already off */
+
 	ret = dev->platform_data->flisclk_ctrl(sd, 0);
 	if (ret)
 		dev_err(&client->dev, "flisclk failed\n");
@@ -592,6 +599,7 @@ static int power_down(struct v4l2_subdev *sd)
 	if (ret)
 		dev_err(&client->dev, "vprog failed.\n");
 
+	dev->power_on = 0;
 	return ret;
 }
 
@@ -669,6 +677,9 @@ static int ov2722_set_fmt(struct v4l2_subdev *sd,
 
 	mutex_lock(&dev->input_lock);
 
+	/* s_power has not been called yet for std v4l2 clients (camorama) */
+	power_up(sd);
+
 	dev->pixels_per_line = dev->res->pixels_per_line;
 	dev->lines_per_frame = dev->res->lines_per_frame;
 
@@ -959,6 +970,7 @@ static int ov2722_probe(struct i2c_client *client)
 		return -ENOMEM;
 
 	mutex_init(&dev->input_lock);
+	dev->power_on = -1;
 
 	dev->res = &ov2722_res_preview[0];
 	v4l2_i2c_subdev_init(&dev->sd, client, &ov2722_ops);

drivers/staging/media/atomisp/i2c/ov2722.h

@@ -198,7 +198,7 @@ struct ov2722_device {
 	struct ov2722_resolution *res;
 
 	struct camera_sensor_platform_data *platform_data;
-	int run_mode;
+	int power_on;
 	u16 pixels_per_line;
 	u16 lines_per_frame;
 	u8 type;