[PATCH 02/23] drm/exynos: calculate vrefresh instead of use a fixed value

[Joonyoung Shim]

On 06/24/2015 06:35 AM, Gustavo Padovan wrote:
> From: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
> 
> When mode's vrefresh is zero we should ask DRM core to calculate vrefresh
> for us so we can get the correct value instead of relying on fixed value
> defined in a macro. But if vrefresh is still zero we should fail the
> update.
> 
> Suggested-by: Daniel Stone <daniels at collabora.com>
> Signed-off-by: Gustavo Padovan <gustavo.padovan at collabora.co.uk>
> ---
>  drivers/gpu/drm/exynos/exynos_drm_fimd.c | 5 +++--
>  1 file changed, 3 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_fimd.c b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> index 1e3bb72..7ba348e 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_fimd.c
> @@ -41,7 +41,6 @@
>   * CPU Interface.
>   */
>  
> -#define FIMD_DEFAULT_FRAMERATE 60
>  #define MIN_FB_WIDTH_FOR_16WORD_BURST 128
>  
>  /* position control register for hardware window 0, 2 ~ 4.*/
> @@ -403,7 +402,9 @@ static bool fimd_mode_fixup(struct exynos_drm_crtc *crtc,
>  		struct drm_display_mode *adjusted_mode)
>  {
>  	if (adjusted_mode->vrefresh == 0)
> -		adjusted_mode->vrefresh = FIMD_DEFAULT_FRAMERATE;
> +		adjusted_mode->vrefresh = drm_mode_vrefresh(mode);
> +	if (adjusted_mode->vrefresh == 0)

If adjusted_mode->vrefresh is not 0, it will check two times whether it
is 0. Check it in first if statement.

Basically, i'm not sure, why should we check whether
adjusted_mode->vrefresh is 0 at first? Can't we use just

        adjusted_mode->vrefresh = drm_mode_vrefresh(mode);
	if (adjusted_mode->vrefresh == 0)
		...

without the first checking?

> +		return false;
>  
>  	return true;
>  }
>