Re: [PATCH v11 13/15] media: vivid: add fixed point test controls

[Hans Verkuil]

On 22/11/2023 08:23, Shengjiu Wang wrote:
> Add fixed point test controls, one is for Q4.16 format
> another one is for Q63 format.
> 
> Signed-off-by: Shengjiu Wang <shengjiu.wang@xxxxxxx>
> ---
>  drivers/media/test-drivers/vivid/vivid-core.h |  2 ++
>  .../media/test-drivers/vivid/vivid-ctrls.c    | 26 +++++++++++++++++++
>  include/media/v4l2-ctrls.h                    |  3 +++
>  3 files changed, 31 insertions(+)
> 
> diff --git a/drivers/media/test-drivers/vivid/vivid-core.h b/drivers/media/test-drivers/vivid/vivid-core.h
> index cfb8e66083f6..f65465191bc9 100644
> --- a/drivers/media/test-drivers/vivid/vivid-core.h
> +++ b/drivers/media/test-drivers/vivid/vivid-core.h
> @@ -222,6 +222,8 @@ struct vivid_dev {
>  	struct v4l2_ctrl		*boolean;
>  	struct v4l2_ctrl		*int32;
>  	struct v4l2_ctrl		*int64;
> +	struct v4l2_ctrl		*int32_q16;
> +	struct v4l2_ctrl		*int64_q63;
>  	struct v4l2_ctrl		*menu;
>  	struct v4l2_ctrl		*string;
>  	struct v4l2_ctrl		*bitmask;
> diff --git a/drivers/media/test-drivers/vivid/vivid-ctrls.c b/drivers/media/test-drivers/vivid/vivid-ctrls.c
> index f2b20e25a7a4..2444ea95b285 100644
> --- a/drivers/media/test-drivers/vivid/vivid-ctrls.c
> +++ b/drivers/media/test-drivers/vivid/vivid-ctrls.c
> @@ -38,6 +38,8 @@
>  #define VIVID_CID_U8_PIXEL_ARRAY	(VIVID_CID_CUSTOM_BASE + 14)
>  #define VIVID_CID_S32_ARRAY		(VIVID_CID_CUSTOM_BASE + 15)
>  #define VIVID_CID_S64_ARRAY		(VIVID_CID_CUSTOM_BASE + 16)
> +#define VIVID_CID_INT_Q4_16		(VIVID_CID_CUSTOM_BASE + 17)
> +#define VIVID_CID_INT64_Q63		(VIVID_CID_CUSTOM_BASE + 18)
>  
>  #define VIVID_CID_VIVID_BASE		(0x00f00000 | 0xf000)
>  #define VIVID_CID_VIVID_CLASS		(0x00f00000 | 1)
> @@ -182,6 +184,28 @@ static const struct v4l2_ctrl_config vivid_ctrl_int64 = {
>  	.step = 1,
>  };
>  
> +static const struct v4l2_ctrl_config vivid_ctrl_int32_q16 = {
> +	.ops = &vivid_user_gen_ctrl_ops,
> +	.id = VIVID_CID_INT_Q4_16,
> +	.name = "Integer 32 Bits Q4.16",
> +	.type = V4L2_CTRL_TYPE_INTEGER,
> +	.min = v4l2_ctrl_fp_compose(-16, 0, 16),
> +	.max = v4l2_ctrl_fp_compose(15, 0xffff, 16),
> +	.step = 1,
> +	.fraction_bits = 16,
> +};
> +
> +static const struct v4l2_ctrl_config vivid_ctrl_int64_q63 = {
> +	.ops = &vivid_user_gen_ctrl_ops,
> +	.id = VIVID_CID_INT64_Q63,
> +	.name = "Integer 64 Bits Q63",
> +	.type = V4L2_CTRL_TYPE_INTEGER64,
> +	.min = v4l2_ctrl_fp_compose(-1, 0, 63),
> +	.max = v4l2_ctrl_fp_compose(0, LLONG_MAX, 63),
> +	.step = 1,
> +	.fraction_bits = 63,
> +};
> +
>  static const struct v4l2_ctrl_config vivid_ctrl_u32_array = {
>  	.ops = &vivid_user_gen_ctrl_ops,
>  	.id = VIVID_CID_U32_ARRAY,
> @@ -1670,6 +1694,8 @@ int vivid_create_controls(struct vivid_dev *dev, bool show_ccs_cap,
>  	dev->button = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_button, NULL);
>  	dev->int32 = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_int32, NULL);
>  	dev->int64 = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_int64, NULL);
> +	dev->int32_q16 = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_int32_q16, NULL);
> +	dev->int64_q63 = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_int64_q63, NULL);
>  	dev->boolean = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_boolean, NULL);
>  	dev->menu = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_menu, NULL);
>  	dev->string = v4l2_ctrl_new_custom(hdl_user_gen, &vivid_ctrl_string, NULL);
> diff --git a/include/media/v4l2-ctrls.h b/include/media/v4l2-ctrls.h
> index c35514c5bf88..d18fd116238b 100644
> --- a/include/media/v4l2-ctrls.h
> +++ b/include/media/v4l2-ctrls.h
> @@ -1593,4 +1593,7 @@ void v4l2_ctrl_type_op_log(const struct v4l2_ctrl *ctrl);
>   */
>  int v4l2_ctrl_type_op_validate(const struct v4l2_ctrl *ctrl, union v4l2_ctrl_ptr ptr);
>  
> +/* Composite function for integer and fractional bits */

This comment needs to be expanded a bit:

/*
 * Fixed point compose helper define. This helper maps to the value
 * i + f / (1 << fraction_bits).
 */

> +#define v4l2_ctrl_fp_compose(i, f, fraction_bits) (((s64)(i) << fraction_bits) + (f))
> +
>  #endif

Regards,

	Hans