[Intel-gfx] [PATCH 1/4] drm/i915/dsi: abstract dsi bpp derivation from pixel format

[Ville Syrjälä]

On Tue, May 12, 2015 at 05:20:38PM +0300, Jani Nikula wrote:
> Nuke three copies of the same switch case.
> 
> Hopefully we can switch to a drm generic function later on, but that
> will require us to swich to enum mipi_dsi_pixel_format first.
> 
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_dsi_pll.c | 67 +++++++++++++-----------------------
>  1 file changed, 24 insertions(+), 43 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dsi_pll.c b/drivers/gpu/drm/i915/intel_dsi_pll.c
> index cfd527765156..9ada06ec88e5 100644
> --- a/drivers/gpu/drm/i915/intel_dsi_pll.c
> +++ b/drivers/gpu/drm/i915/intel_dsi_pll.c
> @@ -38,6 +38,27 @@
>  #define DSI_HFP_PACKET_EXTRA_SIZE	6
>  #define DSI_EOTP_PACKET_SIZE		4
>  
> +static int dsi_pixel_format_bpp(int pixel_format)
> +{
> +	int bpp;
> +
> +	switch (pixel_format) {
> +	default:
> +	case VID_MODE_FORMAT_RGB888:
> +	case VID_MODE_FORMAT_RGB666_LOOSE:
> +		bpp = 24;
> +		break;
> +	case VID_MODE_FORMAT_RGB666:
> +		bpp = 18;
> +		break;
> +	case VID_MODE_FORMAT_RGB565:
> +		bpp = 16;
> +		break;
> +	}
> +
> +	return bpp;
> +}

Optional bikeshed: Could return directly from the switch cases and avoid
the local variable.

But anyway:
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

> +
>  struct dsi_mnp {
>  	u32 dsi_pll_ctrl;
>  	u32 dsi_pll_div;
> @@ -65,19 +86,7 @@ static u32 dsi_rr_formula(const struct drm_display_mode *mode,
>  	u32 dsi_bit_clock_hz;
>  	u32 dsi_clk;
>  
> -	switch (pixel_format) {
> -	default:
> -	case VID_MODE_FORMAT_RGB888:
> -	case VID_MODE_FORMAT_RGB666_LOOSE:
> -		bpp = 24;
> -		break;
> -	case VID_MODE_FORMAT_RGB666:
> -		bpp = 18;
> -		break;
> -	case VID_MODE_FORMAT_RGB565:
> -		bpp = 16;
> -		break;
> -	}
> +	bpp = dsi_pixel_format_bpp(pixel_format);
>  
>  	hactive = mode->hdisplay;
>  	vactive = mode->vdisplay;
> @@ -137,21 +146,7 @@ static u32 dsi_rr_formula(const struct drm_display_mode *mode,
>  static u32 dsi_clk_from_pclk(u32 pclk, int pixel_format, int lane_count)
>  {
>  	u32 dsi_clk_khz;
> -	u32 bpp;
> -
> -	switch (pixel_format) {
> -	default:
> -	case VID_MODE_FORMAT_RGB888:
> -	case VID_MODE_FORMAT_RGB666_LOOSE:
> -		bpp = 24;
> -		break;
> -	case VID_MODE_FORMAT_RGB666:
> -		bpp = 18;
> -		break;
> -	case VID_MODE_FORMAT_RGB565:
> -		bpp = 16;
> -		break;
> -	}
> +	u32 bpp = dsi_pixel_format_bpp(pixel_format);
>  
>  	/* DSI data rate = pixel clock * bits per pixel / lane count
>  	   pixel clock is converted from KHz to Hz */
> @@ -285,21 +280,7 @@ void vlv_disable_dsi_pll(struct intel_encoder *encoder)
>  
>  static void assert_bpp_mismatch(int pixel_format, int pipe_bpp)
>  {
> -	int bpp;
> -
> -	switch (pixel_format) {
> -	default:
> -	case VID_MODE_FORMAT_RGB888:
> -	case VID_MODE_FORMAT_RGB666_LOOSE:
> -		bpp = 24;
> -		break;
> -	case VID_MODE_FORMAT_RGB666:
> -		bpp = 18;
> -		break;
> -	case VID_MODE_FORMAT_RGB565:
> -		bpp = 16;
> -		break;
> -	}
> +	int bpp = dsi_pixel_format_bpp(pixel_format);
>  
>  	WARN(bpp != pipe_bpp,
>  	     "bpp match assertion failure (expected %d, current %d)\n",
> -- 
> 2.1.4

-- 
Ville Syrjälä
Intel OTC