Re: [PATCH v5 3/4] drm/mipi-dsi: add mipi_dsi_compression_mode_ext()

From: Marijn Suijten
Date: Sat Apr 13 2024 - 17:30:26 EST


On 2024-04-08 02:53:52, Dmitry Baryshkov wrote:
> Add the extended version of mipi_dsi_compression_mode(). It provides
> a way to specify the algorithm and PPS selector.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

Reviewed-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx>

Something doesn't stick with me on the _ext() naming, but I don't have something
better to propose.

- Marijn

> ---
> drivers/gpu/drm/drm_mipi_dsi.c | 41 ++++++++++++++++++++++++++++++++++-------
> include/drm/drm_mipi_dsi.h | 9 +++++++++
> 2 files changed, 43 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
> index 9874ff6d4718..795001bb7ff1 100644
> --- a/drivers/gpu/drm/drm_mipi_dsi.c
> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
> @@ -645,29 +645,56 @@ int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
> EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size);
>
> /**
> - * mipi_dsi_compression_mode() - enable/disable DSC on the peripheral
> + * mipi_dsi_compression_mode_ext() - enable/disable DSC on the peripheral
> * @dsi: DSI peripheral device
> * @enable: Whether to enable or disable the DSC
> + * @algo: Selected compression algorithm
> + * @pps_selector: Select PPS from the table of pre-stored or uploaded PPS entries
> *
> - * Enable or disable Display Stream Compression on the peripheral using the
> - * default Picture Parameter Set and VESA DSC 1.1 algorithm.
> + * Enable or disable Display Stream Compression on the peripheral.
> *
> * Return: 0 on success or a negative error code on failure.
> */
> -int mipi_dsi_compression_mode(struct mipi_dsi_device *dsi, bool enable)
> +int mipi_dsi_compression_mode_ext(struct mipi_dsi_device *dsi, bool enable,
> + enum mipi_dsi_compression_algo algo,
> + unsigned int pps_selector)
> {
> - /* Note: Needs updating for non-default PPS or algorithm */
> - u8 tx[2] = { enable << 0, 0 };
> + u8 tx[2] = { };
> struct mipi_dsi_msg msg = {
> .channel = dsi->channel,
> .type = MIPI_DSI_COMPRESSION_MODE,
> .tx_len = sizeof(tx),
> .tx_buf = tx,
> };
> - int ret = mipi_dsi_device_transfer(dsi, &msg);
> + int ret;
> +
> + if (algo > 3 || pps_selector > 3)
> + return -EINVAL;
> +
> + tx[0] = (enable << 0) |
> + (algo << 1) |
> + (pps_selector << 4);
> +
> + ret = mipi_dsi_device_transfer(dsi, &msg);
>
> return (ret < 0) ? ret : 0;
> }
> +EXPORT_SYMBOL(mipi_dsi_compression_mode_ext);
> +
> +/**
> + * mipi_dsi_compression_mode() - enable/disable DSC on the peripheral
> + * @dsi: DSI peripheral device
> + * @enable: Whether to enable or disable the DSC
> + *
> + * Enable or disable Display Stream Compression on the peripheral using the
> + * default Picture Parameter Set and VESA DSC 1.1 algorithm.
> + *
> + * Return: 0 on success or a negative error code on failure.
> + */
> +int mipi_dsi_compression_mode(struct mipi_dsi_device *dsi, bool enable)
> +{
> + return mipi_dsi_compression_mode_ext(dsi, enable, MIPI_DSI_COMPRESSION_DSC, 0);
> +}
> EXPORT_SYMBOL(mipi_dsi_compression_mode);
>
> /**
> diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
> index 3011d33eccbd..82b1cc434ea3 100644
> --- a/include/drm/drm_mipi_dsi.h
> +++ b/include/drm/drm_mipi_dsi.h
> @@ -226,6 +226,12 @@ static inline int mipi_dsi_pixel_format_to_bpp(enum mipi_dsi_pixel_format fmt)
> return -EINVAL;
> }
>
> +enum mipi_dsi_compression_algo {
> + MIPI_DSI_COMPRESSION_DSC = 0,
> + MIPI_DSI_COMPRESSION_VENDOR = 3,
> + /* other two values are reserved, DSI 1.3 */
> +};
> +
> struct mipi_dsi_device *
> mipi_dsi_device_register_full(struct mipi_dsi_host *host,
> const struct mipi_dsi_device_info *info);
> @@ -242,6 +248,9 @@ int mipi_dsi_turn_on_peripheral(struct mipi_dsi_device *dsi);
> int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi,
> u16 value);
> int mipi_dsi_compression_mode(struct mipi_dsi_device *dsi, bool enable);
> +int mipi_dsi_compression_mode_ext(struct mipi_dsi_device *dsi, bool enable,
> + enum mipi_dsi_compression_algo algo,
> + unsigned int pps_selector);
> int mipi_dsi_picture_parameter_set(struct mipi_dsi_device *dsi,
> const struct drm_dsc_picture_parameter_set *pps);
>
>
> --
> 2.39.2
>