Re: [PATCH 12/16] media: i2c: ov9282: Make V4L2_CID_HBLANK r/w

[Jacopo Mondi <jacopo@jmondi.org>]

Hi Dave

On Wed, Oct 05, 2022 at 04:28:05PM +0100, Dave Stevenson wrote:
> There's no reason why HBLANK has to be read-only as it
> only changes the TIMING_HTS register in the sensor.
>
> Remove the READ_ONLY flag, and add the relevant handling
> for it.
>
> The minimum value also varies based on whether continuous clock
> mode is being used or not, so allow hblank_min to depend on
> that.

Interesting, do you know why they're different and why the continous
version is smaller ?

>
> Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
> ---
>  drivers/media/i2c/ov9282.c | 34 +++++++++++++++++++++-------------
>  1 file changed, 21 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/media/i2c/ov9282.c b/drivers/media/i2c/ov9282.c
> index 12cbe401fd78..8e86aa7e4b2a 100644
> --- a/drivers/media/i2c/ov9282.c
> +++ b/drivers/media/i2c/ov9282.c
> @@ -22,6 +22,9 @@
>  #define OV9282_MODE_STANDBY	0x00
>  #define OV9282_MODE_STREAMING	0x01
>
> +#define OV9282_REG_TIMING_HTS	0x380c
> +#define OV9282_TIMING_HTS_MAX	0x7fff
> +
>  /* Lines per frame */
>  #define OV9282_REG_LPFR		0x380e
>
> @@ -99,7 +102,8 @@ struct ov9282_reg_list {
>   * struct ov9282_mode - ov9282 sensor mode structure
>   * @width: Frame width
>   * @height: Frame height
> - * @hblank: Horizontal blanking in lines
> + * @hblank_min: Minimum horizontal blanking in lines for non-continuous[0] and
> + *		continuous[1] clock modes
>   * @vblank: Vertical blanking in lines
>   * @vblank_min: Minimum vertical blanking in lines
>   * @vblank_max: Maximum vertical blanking in lines
> @@ -109,7 +113,7 @@ struct ov9282_reg_list {
>  struct ov9282_mode {
>  	u32 width;
>  	u32 height;
> -	u32 hblank;
> +	u32 hblank_min[2];
>  	u32 vblank;
>  	u32 vblank_min;
>  	u32 vblank_max;
> @@ -249,8 +253,6 @@ static const struct ov9282_reg mode_1280x720_regs[] = {
>  	{0x3809, 0x00},
>  	{0x380a, 0x02},
>  	{0x380b, 0xd0},
> -	{0x380c, 0x02},
> -	{0x380d, 0xfd},
>  	{0x3810, 0x00},
>  	{0x3811, 0x08},
>  	{0x3812, 0x00},
> @@ -273,7 +275,7 @@ static const struct ov9282_mode supported_modes[] = {
>  	{
>  		.width = 1280,
>  		.height = 720,
> -		.hblank = 250,
> +		.hblank_min = { 250, 176 },
>  		.vblank = 1022,
>  		.vblank_min = 41,
>  		.vblank_max = 51540,
> @@ -399,15 +401,17 @@ static int ov9282_write_regs(struct ov9282 *ov9282,
>  static int ov9282_update_controls(struct ov9282 *ov9282,
>  				  const struct ov9282_mode *mode)
>  {
> +	u32 hblank_min;
>  	int ret;
>
>  	ret = __v4l2_ctrl_s_ctrl(ov9282->link_freq_ctrl, mode->link_freq_idx);
>  	if (ret)
>  		return ret;
>
> -	ret = __v4l2_ctrl_s_ctrl(ov9282->hblank_ctrl, mode->hblank);
> -	if (ret)
> -		return ret;
> +	hblank_min = mode->hblank_min[ov9282->noncontinuous_clock ? 0 : 1];
> +	ret =  __v4l2_ctrl_modify_range(ov9282->hblank_ctrl, hblank_min,
> +					OV9282_TIMING_HTS_MAX - mode->width, 1,
> +					hblank_min);
>
>  	return __v4l2_ctrl_modify_range(ov9282->vblank_ctrl, mode->vblank_min,
>  					mode->vblank_max, 1, mode->vblank);
> @@ -539,6 +543,10 @@ static int ov9282_set_ctrl(struct v4l2_ctrl *ctrl)
>  	case V4L2_CID_VFLIP:
>  		ret = ov9282_set_ctrl_vflip(ov9282, ctrl->val);
>  		break;
> +	case V4L2_CID_HBLANK:
> +		ret = ov9282_write_reg(ov9282, OV9282_REG_TIMING_HTS, 2,
> +				       (ctrl->val + ov9282->cur_mode->width) >> 1);
> +		break;
>  	default:
>  		dev_err(ov9282->dev, "Invalid control %d", ctrl->id);
>  		ret = -EINVAL;
> @@ -1033,6 +1041,7 @@ static int ov9282_init_controls(struct ov9282 *ov9282)
>  	struct v4l2_ctrl_handler *ctrl_hdlr = &ov9282->ctrl_handler;
>  	const struct ov9282_mode *mode = ov9282->cur_mode;
>  	struct v4l2_fwnode_device_properties props;
> +	u32 hblank_min;
>  	u32 lpfr;
>  	int ret;
>
> @@ -1091,14 +1100,13 @@ static int ov9282_init_controls(struct ov9282 *ov9282)
>  	if (ov9282->link_freq_ctrl)
>  		ov9282->link_freq_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
>
> +	hblank_min = mode->hblank_min[ov9282->noncontinuous_clock ? 0 : 1];
>  	ov9282->hblank_ctrl = v4l2_ctrl_new_std(ctrl_hdlr,
>  						&ov9282_ctrl_ops,
>  						V4L2_CID_HBLANK,
> -						OV9282_REG_MIN,
> -						OV9282_REG_MAX,
> -						1, mode->hblank);
> -	if (ov9282->hblank_ctrl)
> -		ov9282->hblank_ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
> +						hblank_min,
> +						OV9282_TIMING_HTS_MAX - mode->width,
> +						1, hblank_min);
>
>  	ret = v4l2_fwnode_device_parse(ov9282->dev, &props);
>  	if (!ret) {
> --
> 2.34.1
>