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[PATCH 2/3] media: i2c: ov9282: add led_mode v4l2 control

Richard Leitner posted 3 patches 11 months, 1 week ago
[PATCH 2/3] media: i2c: ov9282: add led_mode v4l2 control
Posted by Richard Leitner 11 months, 1 week ago 
Add V4L2_CID_FLASH_LED_MODE support using the "strobe output enable"
feature of the sensor. This implements following modes:

 - V4L2_FLASH_LED_MODE_NONE, which disables the strobe output
 - V4L2_FLASH_LED_MODE_FLASH, which enables the strobe output

All values are based on the OV9281 datasheet v1.53 (january 2019) and
tested using an ov9281 VisionComponents module.

Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
---
 drivers/media/i2c/ov9282.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
index f42e0d439753e74d14e3a3592029e48f49234927..c98ba466e9aea29baff0b13578d760bf69c958c5 100644
--- a/drivers/media/i2c/ov9282.c
+++ b/drivers/media/i2c/ov9282.c
@@ -192,6 +192,7 @@ struct ov9282_mode {
  * @exp_ctrl: Pointer to exposure control
  * @again_ctrl: Pointer to analog gain control
  * @pixel_rate: Pointer to pixel rate control
+ * @flash_led_mode: Pointer to flash led mode control
  * @vblank: Vertical blanking in lines
  * @noncontinuous_clock: Selection of CSI2 noncontinuous clock mode
  * @cur_mode: Pointer to current selected sensor mode
@@ -214,6 +215,7 @@ struct ov9282 {
 		struct v4l2_ctrl *again_ctrl;
 	};
 	struct v4l2_ctrl *pixel_rate;
+	struct v4l2_ctrl *flash_led_mode;
 	u32 vblank;
 	bool noncontinuous_clock;
 	const struct ov9282_mode *cur_mode;
@@ -670,6 +672,23 @@ static int ov9282_set_ctrl_vflip(struct ov9282 *ov9282, int value)
 				current_val);
 }
 
+static int ov9282_set_ctrl_flash_led_mode(struct ov9282 *ov9282, int mode)
+{
+	u32 current_val;
+	int ret = ov9282_read_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1,
+				  &current_val);
+	if (ret)
+		return ret;
+
+	if (mode == V4L2_FLASH_LED_MODE_FLASH)
+		current_val |= OV9282_OUTPUT_ENABLE6_STROBE;
+	else
+		current_val &= ~OV9282_OUTPUT_ENABLE6_STROBE;
+
+	return ov9282_write_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1,
+				current_val);
+}
+
 /**
  * ov9282_set_ctrl() - Set subdevice control
  * @ctrl: pointer to v4l2_ctrl structure
@@ -736,6 +755,9 @@ static int ov9282_set_ctrl(struct v4l2_ctrl *ctrl)
 		ret = ov9282_write_reg(ov9282, OV9282_REG_TIMING_HTS, 2,
 				       (ctrl->val + ov9282->cur_mode->width) >> 1);
 		break;
+	case V4L2_CID_FLASH_LED_MODE:
+		ret = ov9282_set_ctrl_flash_led_mode(ov9282, ctrl->val);
+		break;
 	default:
 		dev_err(ov9282->dev, "Invalid control %d", ctrl->id);
 		ret = -EINVAL;
@@ -1391,6 +1413,13 @@ static int ov9282_init_controls(struct ov9282 *ov9282)
 						OV9282_TIMING_HTS_MAX - mode->width,
 						1, hblank_min);
 
+	/* Flash/Strobe controls */
+	ov9282->flash_led_mode = v4l2_ctrl_new_std_menu(ctrl_hdlr, &ov9282_ctrl_ops,
+							V4L2_CID_FLASH_LED_MODE,
+							V4L2_FLASH_LED_MODE_TORCH,
+							(1 << V4L2_FLASH_LED_MODE_TORCH),
+							V4L2_FLASH_LED_MODE_NONE);
+
 	ret = v4l2_fwnode_device_parse(ov9282->dev, &props);
 	if (!ret) {
 		/* Failure sets ctrl_hdlr->error, which we check afterwards anyway */

-- 
2.47.2
Re: [PATCH 2/3] media: i2c: ov9282: add led_mode v4l2 control
Posted by Dave Stevenson 11 months, 1 week ago 
Hi Richard

On Mon, 3 Mar 2025 at 22:59, Richard Leitner <richard.leitner@linux.dev> wrote:
>
> Add V4L2_CID_FLASH_LED_MODE support using the "strobe output enable"
> feature of the sensor. This implements following modes:
>
>  - V4L2_FLASH_LED_MODE_NONE, which disables the strobe output
>  - V4L2_FLASH_LED_MODE_FLASH, which enables the strobe output
>
> All values are based on the OV9281 datasheet v1.53 (january 2019) and
> tested using an ov9281 VisionComponents module.
>
> Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
> ---
>  drivers/media/i2c/ov9282.c | 29 +++++++++++++++++++++++++++++
>  1 file changed, 29 insertions(+)
>
> diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
> index f42e0d439753e74d14e3a3592029e48f49234927..c98ba466e9aea29baff0b13578d760bf69c958c5 100644
> --- a/drivers/media/i2c/ov9282.c
> +++ b/drivers/media/i2c/ov9282.c
> @@ -192,6 +192,7 @@ struct ov9282_mode {
>   * @exp_ctrl: Pointer to exposure control
>   * @again_ctrl: Pointer to analog gain control
>   * @pixel_rate: Pointer to pixel rate control
> + * @flash_led_mode: Pointer to flash led mode control
>   * @vblank: Vertical blanking in lines
>   * @noncontinuous_clock: Selection of CSI2 noncontinuous clock mode
>   * @cur_mode: Pointer to current selected sensor mode
> @@ -214,6 +215,7 @@ struct ov9282 {
>                 struct v4l2_ctrl *again_ctrl;
>         };
>         struct v4l2_ctrl *pixel_rate;
> +       struct v4l2_ctrl *flash_led_mode;

As with 3/3, you only use this control from within ov9282_set_ctrl
where you are given the struct v4l2_ctrl, so there is no need to store
it in the device state structure.

>         u32 vblank;
>         bool noncontinuous_clock;
>         const struct ov9282_mode *cur_mode;
> @@ -670,6 +672,23 @@ static int ov9282_set_ctrl_vflip(struct ov9282 *ov9282, int value)
>                                 current_val);
>  }
>
> +static int ov9282_set_ctrl_flash_led_mode(struct ov9282 *ov9282, int mode)
> +{
> +       u32 current_val;
> +       int ret = ov9282_read_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1,
> +                                 &current_val);
> +       if (ret)
> +               return ret;
> +
> +       if (mode == V4L2_FLASH_LED_MODE_FLASH)
> +               current_val |= OV9282_OUTPUT_ENABLE6_STROBE;
> +       else
> +               current_val &= ~OV9282_OUTPUT_ENABLE6_STROBE;
> +
> +       return ov9282_write_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1,
> +                               current_val);
> +}
> +
>  /**
>   * ov9282_set_ctrl() - Set subdevice control
>   * @ctrl: pointer to v4l2_ctrl structure
> @@ -736,6 +755,9 @@ static int ov9282_set_ctrl(struct v4l2_ctrl *ctrl)
>                 ret = ov9282_write_reg(ov9282, OV9282_REG_TIMING_HTS, 2,
>                                        (ctrl->val + ov9282->cur_mode->width) >> 1);
>                 break;
> +       case V4L2_CID_FLASH_LED_MODE:
> +               ret = ov9282_set_ctrl_flash_led_mode(ov9282, ctrl->val);
> +               break;
>         default:
>                 dev_err(ov9282->dev, "Invalid control %d", ctrl->id);
>                 ret = -EINVAL;
> @@ -1391,6 +1413,13 @@ static int ov9282_init_controls(struct ov9282 *ov9282)
>                                                 OV9282_TIMING_HTS_MAX - mode->width,
>                                                 1, hblank_min);
>
> +       /* Flash/Strobe controls */
> +       ov9282->flash_led_mode = v4l2_ctrl_new_std_menu(ctrl_hdlr, &ov9282_ctrl_ops,
> +                                                       V4L2_CID_FLASH_LED_MODE,
> +                                                       V4L2_FLASH_LED_MODE_TORCH,
> +                                                       (1 << V4L2_FLASH_LED_MODE_TORCH),
> +                                                       V4L2_FLASH_LED_MODE_NONE);
> +
>         ret = v4l2_fwnode_device_parse(ov9282->dev, &props);
>         if (!ret) {
>                 /* Failure sets ctrl_hdlr->error, which we check afterwards anyway */
>
> --
> 2.47.2
>
>
Re: [PATCH 2/3] media: i2c: ov9282: add led_mode v4l2 control
Posted by Richard Leitner 11 months, 1 week ago 
Hi Dave,
thanks for the review.
I really appreciate your quick responses.

On Tue, Mar 04, 2025 at 05:27:34PM +0000, Dave Stevenson wrote:
> Hi Richard
> 
> On Mon, 3 Mar 2025 at 22:59, Richard Leitner <richard.leitner@linux.dev> wrote:
> >
> > Add V4L2_CID_FLASH_LED_MODE support using the "strobe output enable"
> > feature of the sensor. This implements following modes:
> >
> >  - V4L2_FLASH_LED_MODE_NONE, which disables the strobe output
> >  - V4L2_FLASH_LED_MODE_FLASH, which enables the strobe output
> >
> > All values are based on the OV9281 datasheet v1.53 (january 2019) and
> > tested using an ov9281 VisionComponents module.
> >
> > Signed-off-by: Richard Leitner <richard.leitner@linux.dev>
> > ---
> >  drivers/media/i2c/ov9282.c | 29 +++++++++++++++++++++++++++++
> >  1 file changed, 29 insertions(+)
> >
> > diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
> > index f42e0d439753e74d14e3a3592029e48f49234927..c98ba466e9aea29baff0b13578d760bf69c958c5 100644
> > --- a/drivers/media/i2c/ov9282.c
> > +++ b/drivers/media/i2c/ov9282.c
> > @@ -192,6 +192,7 @@ struct ov9282_mode {
> >   * @exp_ctrl: Pointer to exposure control
> >   * @again_ctrl: Pointer to analog gain control
> >   * @pixel_rate: Pointer to pixel rate control
> > + * @flash_led_mode: Pointer to flash led mode control
> >   * @vblank: Vertical blanking in lines
> >   * @noncontinuous_clock: Selection of CSI2 noncontinuous clock mode
> >   * @cur_mode: Pointer to current selected sensor mode
> > @@ -214,6 +215,7 @@ struct ov9282 {
> >                 struct v4l2_ctrl *again_ctrl;
> >         };
> >         struct v4l2_ctrl *pixel_rate;
> > +       struct v4l2_ctrl *flash_led_mode;
> 
> As with 3/3, you only use this control from within ov9282_set_ctrl
> where you are given the struct v4l2_ctrl, so there is no need to store
> it in the device state structure.

Sure. Thanks for bringing this up. Will fix that in v2.

> 
> >         u32 vblank;
> >         bool noncontinuous_clock;
> >         const struct ov9282_mode *cur_mode;
> > @@ -670,6 +672,23 @@ static int ov9282_set_ctrl_vflip(struct ov9282 *ov9282, int value)
> >                                 current_val);
> >  }
> >
> > +static int ov9282_set_ctrl_flash_led_mode(struct ov9282 *ov9282, int mode)
> > +{
> > +       u32 current_val;
> > +       int ret = ov9282_read_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1,
> > +                                 &current_val);
> > +       if (ret)
> > +               return ret;
> > +
> > +       if (mode == V4L2_FLASH_LED_MODE_FLASH)
> > +               current_val |= OV9282_OUTPUT_ENABLE6_STROBE;
> > +       else
> > +               current_val &= ~OV9282_OUTPUT_ENABLE6_STROBE;
> > +
> > +       return ov9282_write_reg(ov9282, OV9282_REG_OUTPUT_ENABLE6, 1,
> > +                               current_val);
> > +}
> > +
> >  /**
> >   * ov9282_set_ctrl() - Set subdevice control
> >   * @ctrl: pointer to v4l2_ctrl structure
> > @@ -736,6 +755,9 @@ static int ov9282_set_ctrl(struct v4l2_ctrl *ctrl)
> >                 ret = ov9282_write_reg(ov9282, OV9282_REG_TIMING_HTS, 2,
> >                                        (ctrl->val + ov9282->cur_mode->width) >> 1);
> >                 break;
> > +       case V4L2_CID_FLASH_LED_MODE:
> > +               ret = ov9282_set_ctrl_flash_led_mode(ov9282, ctrl->val);
> > +               break;
> >         default:
> >                 dev_err(ov9282->dev, "Invalid control %d", ctrl->id);
> >                 ret = -EINVAL;
> > @@ -1391,6 +1413,13 @@ static int ov9282_init_controls(struct ov9282 *ov9282)
> >                                                 OV9282_TIMING_HTS_MAX - mode->width,
> >                                                 1, hblank_min);
> >
> > +       /* Flash/Strobe controls */
> > +       ov9282->flash_led_mode = v4l2_ctrl_new_std_menu(ctrl_hdlr, &ov9282_ctrl_ops,
> > +                                                       V4L2_CID_FLASH_LED_MODE,
> > +                                                       V4L2_FLASH_LED_MODE_TORCH,
> > +                                                       (1 << V4L2_FLASH_LED_MODE_TORCH),
> > +                                                       V4L2_FLASH_LED_MODE_NONE);
> > +
> >         ret = v4l2_fwnode_device_parse(ov9282->dev, &props);
> >         if (!ret) {
> >                 /* Failure sets ctrl_hdlr->error, which we check afterwards anyway */
> >
> > --
> > 2.47.2
> >
> >

regards;rl

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