Hi,

On Thu, Nov 01, 2018 at 09:00:39PM +0100, Paul Kocialkowski wrote:
> Features such as dithering and pixel data edge configuration currently
> rely on the panel registered with the TCON driver. However, bridges are
> also supported in addition panels.
> 
> Instead of retrieving the connector from the panel, pass the encoder
> from the calling function, as is done for other interfaces.
> 
> The connector is then retrieved from the encoder with the dedicated
> helper. Even in the case of bridges, the connector is registered with
> the encoder from our driver and is accessible when iterating connectors.
> 
> Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
> ---
>  drivers/gpu/drm/sun4i/sun4i_tcon.c | 22 +++++++++-------------
>  1 file changed, 9 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> index f949287d926c..262ffb6b0f82 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c
> @@ -478,8 +478,11 @@ static void sun4i_tcon0_mode_set_lvds(struct sun4i_tcon *tcon,
>  }
>  
>  static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
> +				     const struct drm_encoder *encoder,
>  				     const struct drm_display_mode *mode)
>  {
> +	struct drm_connector *connector = sun4i_tcon_get_connector(encoder);
> +	struct drm_display_info display_info = connector->display_info;
>  	unsigned int bp, hsync, vsync;
>  	u8 clk_delay;
>  	u32 val = 0;
> @@ -491,8 +494,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
>  	sun4i_tcon0_mode_set_common(tcon, mode);
>  
>  	/* Set dithering if needed */
> -	if (tcon->panel)
> -		sun4i_tcon0_mode_set_dithering(tcon, tcon->panel->connector);
> +	sun4i_tcon0_mode_set_dithering(tcon, connector);
>  
>  	/* Adjust clock delay */
>  	clk_delay = sun4i_tcon_get_clk_delay(mode, 0);
> @@ -556,17 +558,11 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon,
>  	 * Following code is a way to avoid quirks all around TCON
>  	 * and DOTCLOCK drivers.
>  	 */
> -	if (tcon->panel) {
> -		struct drm_panel *panel = tcon->panel;
> -		struct drm_connector *connector = panel->connector;
> -		struct drm_display_info display_info = connector->display_info;
> -
> -		if (display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_POSEDGE)
> -			clk_set_phase(tcon->dclk, 240);
> +	if (display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_POSEDGE)
> +		clk_set_phase(tcon->dclk, 240);
>  
> -		if (display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_NEGEDGE)
> -			clk_set_phase(tcon->dclk, 0);
> -	}
> +	if (display_info.bus_flags & DRM_BUS_FLAG_PIXDATA_NEGEDGE)
> +		clk_set_phase(tcon->dclk, 0);

You're doing multiple things here: you're changing the function API,
and then moving the display info checks outside of the tcon->panel
condition.

You should do two separate patches for that.

Maxime

-- 
Maxime Ripard, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com