[PATCH v3] drm/dsi: Implement set tear scanline

[Jani Nikula]

On Tue, 07 Jun 2016, Vinay Simha BN <simhavcs at gmail.com> wrote:
> Provide a small convenience wrapper that transmits
> a set_tear_scanline command.
>
> Cc: Archit Taneja <archit.taneja at gmail.com>
> Cc: John Stultz <john.stultz at linaro.org>
> Cc: Thierry Reding <thierry.reding at gmail.com>
> Cc: Sumit Semwal <sumit.semwal at linaro.org>
> Cc: Jani Nikula <jani.nikula at linux.intel.com>
> Signed-off-by: Vinay Simha BN <simhavcs at gmail.com>

Reviewed-by: Jani Nikula <jani.nikula at intel.com>


>
> --
> v1:
>   * helper function suggested by Thierry
>     for set_tear_scanline
>   * Also includes small build fixes from Sumit Semwal.
>
> v2:
>   * one scanline parameter suggested by jani
>
> v3:
>   * passing the payload properly as suggested by jani
> --
> ---
>  drivers/gpu/drm/drm_mipi_dsi.c | 22 ++++++++++++++++++++++
>  include/drm/drm_mipi_dsi.h     |  1 +
>  2 files changed, 23 insertions(+)
>
> diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c
> index f5d8083..7938ce7 100644
> --- a/drivers/gpu/drm/drm_mipi_dsi.c
> +++ b/drivers/gpu/drm/drm_mipi_dsi.c
> @@ -983,6 +983,28 @@ int mipi_dsi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
>  EXPORT_SYMBOL(mipi_dsi_dcs_set_tear_on);
>  
>  /**
> + * mipi_dsi_set_tear_scanline() - turn on the display module's Tearing Effect
> + * output signal on the TE signal line when display module reaches line N
> + * defined by STS[n:0].
> + * @dsi: DSI peripheral device
> + * @param: STS[10:0]
> + * Return: 0 on success or a negative error code on failure
> + */
> +int mipi_dsi_set_tear_scanline(struct mipi_dsi_device *dsi, u16 param)
> +{
> +	u8 payload[3] = { MIPI_DCS_SET_TEAR_SCANLINE, param >> 8,
> +			  param & 0xff };
> +	ssize_t err;
> +
> +	err = mipi_dsi_generic_write(dsi, payload, sizeof(payload));
> +	if (err < 0)
> +		return err;
> +
> +	return 0;
> +}
> +EXPORT_SYMBOL(mipi_dsi_set_tear_scanline);
> +
> +/**
>   * mipi_dsi_dcs_set_pixel_format() - sets the pixel format for the RGB image
>   *    data used by the interface
>   * @dsi: DSI peripheral device
> diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h
> index 7a9840f..ec55285 100644
> --- a/include/drm/drm_mipi_dsi.h
> +++ b/include/drm/drm_mipi_dsi.h
> @@ -263,6 +263,7 @@ int mipi_dsi_dcs_set_column_address(struct mipi_dsi_device *dsi, u16 start,
>  				    u16 end);
>  int mipi_dsi_dcs_set_page_address(struct mipi_dsi_device *dsi, u16 start,
>  				  u16 end);
> +int mipi_dsi_set_tear_scanline(struct mipi_dsi_device *dsi, u16 param);
>  int mipi_dsi_dcs_set_tear_off(struct mipi_dsi_device *dsi);
>  int mipi_dsi_dcs_set_tear_on(struct mipi_dsi_device *dsi,
>  			     enum mipi_dsi_dcs_tear_mode mode);

-- 
Jani Nikula, Intel Open Source Technology Center