[PATCH] drm: rcar-du: lvds: Get mode from state

[Fabrizio Castro]

Hello Laurent,

Thank you for your patch!

> From: linux-renesas-soc-owner at vger.kernel.org <linux-renesas-soc-owner at vger.kernel.org> On Behalf Of Laurent Pinchart
> Sent: 16 October 2019 00:25
> Subject: [PATCH] drm: rcar-du: lvds: Get mode from state
> 
> The R-Car LVDS encoder driver implements the bridge .mode_set()
> operation for the sole purpose of storing the mode in the LVDS private
> data, to be used later when enabling the encoder.
> 
> Switch to the bridge .atomic_enable() and .atomic_disable() operations
> in order to access the global atomic state, and get the mode from the
> state instead. Remove both the unneeded .mode_set() operation and the
> display_mode and mode fields storing state data from the rcar_lvds
> private structure.
> 
> As a side effect we get the CRTC from the state, replace the CRTC
> pointer retrieved through the bridge's encoder that shouldn't be used by
> atomic drivers.
> 
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas at ideasonboard.com>
> ---
>  drivers/gpu/drm/rcar-du/rcar_lvds.c | 125 ++++++++++++++--------------
>  1 file changed, 61 insertions(+), 64 deletions(-)
> 
> diff --git a/drivers/gpu/drm/rcar-du/rcar_lvds.c b/drivers/gpu/drm/rcar-du/rcar_lvds.c
> index 8c6c172bbf2e..8f355ea07cb5 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_lvds.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_lvds.c
> @@ -65,9 +65,6 @@ struct rcar_lvds {
>  		struct clk *dotclkin[2];	/* External DU clocks */
>  	} clocks;
> 
> -	struct drm_display_mode display_mode;
> -	enum rcar_lvds_mode mode;
> -
>  	struct drm_bridge *companion;
>  	bool dual_link;
>  };
> @@ -402,10 +399,51 @@ EXPORT_SYMBOL_GPL(rcar_lvds_clk_disable);
>   * Bridge
>   */
> 
> -static void rcar_lvds_enable(struct drm_bridge *bridge)
> +static enum rcar_lvds_mode rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds,
> +					const struct drm_connector *connector)
> +{
> +	const struct drm_display_info *info;
> +	enum rcar_lvds_mode mode;
> +
> +	/*
> +	 * There is no API yet to retrieve LVDS mode from a bridge, only panels
> +	 * are supported.
> +	 */
> +	if (!lvds->panel)
> +		return RCAR_LVDS_MODE_JEIDA;
> +
> +	info = &connector->display_info;
> +	if (!info->num_bus_formats || !info->bus_formats) {
> +		dev_err(lvds->dev, "no LVDS bus format reported\n");
> +		return RCAR_LVDS_MODE_JEIDA;
> +	}
> +
> +	switch (info->bus_formats[0]) {
> +	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
> +	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
> +		mode = RCAR_LVDS_MODE_JEIDA;
> +		break;
> +	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
> +		mode = RCAR_LVDS_MODE_VESA;
> +		break;
> +	default:
> +		dev_err(lvds->dev, "unsupported LVDS bus format 0x%04x\n",
> +			info->bus_formats[0]);
> +		return RCAR_LVDS_MODE_JEIDA;
> +	}
> +
> +	if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
> +		mode |= RCAR_LVDS_MODE_MIRROR;
> +
> +	return mode;
> +}
> +
> +static void rcar_lvds_atomic_enable(struct drm_bridge *bridge,
> +				    struct drm_atomic_state *state)
>  {
>  	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> -	const struct drm_display_mode *mode = &lvds->display_mode;
> +	struct drm_connector *connector;
> +	struct drm_crtc *crtc;
>  	u32 lvdhcr;
>  	u32 lvdcr0;
>  	int ret;
> @@ -414,6 +452,11 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
>  	if (ret < 0)
>  		return;
> 
> +	/* Retrieve the connector and CRTC through the atomic state. */
> +	connector = drm_atomic_get_new_connector_for_encoder(state,
> +							     bridge->encoder);
> +	crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
> +
>  	/* Enable the companion LVDS encoder in dual-link mode. */
>  	if (lvds->dual_link && lvds->companion)
>  		lvds->companion->funcs->enable(lvds->companion);

This should call atomic_enable now, therefore I take this won't work as-is on
a system with a companion encoder. Do you mind testing this patch on a dual-LVDS
capable system?

Thanks,
Fab

> @@ -452,18 +495,20 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
>  	 * PLL clock configuration on all instances but the companion in
>  	 * dual-link mode.
>  	 */
> -	if (!lvds->dual_link || lvds->companion)
> +	if (!lvds->dual_link || lvds->companion) {
> +		const struct drm_crtc_state *crtc_state =
> +			drm_atomic_get_new_crtc_state(state, crtc);
> +		const struct drm_display_mode *mode =
> +			&crtc_state->adjusted_mode;
> +
>  		lvds->info->pll_setup(lvds, mode->clock * 1000);
> +	}
> 
>  	/* Set the LVDS mode and select the input. */
> -	lvdcr0 = lvds->mode << LVDCR0_LVMD_SHIFT;
> +	lvdcr0 = rcar_lvds_get_lvds_mode(lvds, connector) << LVDCR0_LVMD_SHIFT;
> 
>  	if (lvds->bridge.encoder) {
> -		/*
> -		 * FIXME: We should really retrieve the CRTC through the state,
> -		 * but how do we get a state pointer?
> -		 */
> -		if (drm_crtc_index(lvds->bridge.encoder->crtc) == 2)
> +		if (drm_crtc_index(crtc) == 2)
>  			lvdcr0 |= LVDCR0_DUSEL;
>  	}
> 
> @@ -520,7 +565,8 @@ static void rcar_lvds_enable(struct drm_bridge *bridge)
>  	}
>  }
> 
> -static void rcar_lvds_disable(struct drm_bridge *bridge)
> +static void rcar_lvds_atomic_disable(struct drm_bridge *bridge,
> +				     struct drm_atomic_state *state)
>  {
>  	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> 
> @@ -558,54 +604,6 @@ static bool rcar_lvds_mode_fixup(struct drm_bridge *bridge,
>  	return true;
>  }
> 
> -static void rcar_lvds_get_lvds_mode(struct rcar_lvds *lvds)
> -{
> -	struct drm_display_info *info = &lvds->connector.display_info;
> -	enum rcar_lvds_mode mode;
> -
> -	/*
> -	 * There is no API yet to retrieve LVDS mode from a bridge, only panels
> -	 * are supported.
> -	 */
> -	if (!lvds->panel)
> -		return;
> -
> -	if (!info->num_bus_formats || !info->bus_formats) {
> -		dev_err(lvds->dev, "no LVDS bus format reported\n");
> -		return;
> -	}
> -
> -	switch (info->bus_formats[0]) {
> -	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
> -	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
> -		mode = RCAR_LVDS_MODE_JEIDA;
> -		break;
> -	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
> -		mode = RCAR_LVDS_MODE_VESA;
> -		break;
> -	default:
> -		dev_err(lvds->dev, "unsupported LVDS bus format 0x%04x\n",
> -			info->bus_formats[0]);
> -		return;
> -	}
> -
> -	if (info->bus_flags & DRM_BUS_FLAG_DATA_LSB_TO_MSB)
> -		mode |= RCAR_LVDS_MODE_MIRROR;
> -
> -	lvds->mode = mode;
> -}
> -
> -static void rcar_lvds_mode_set(struct drm_bridge *bridge,
> -			       const struct drm_display_mode *mode,
> -			       const struct drm_display_mode *adjusted_mode)
> -{
> -	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> -
> -	lvds->display_mode = *adjusted_mode;
> -
> -	rcar_lvds_get_lvds_mode(lvds);
> -}
> -
>  static int rcar_lvds_attach(struct drm_bridge *bridge)
>  {
>  	struct rcar_lvds *lvds = bridge_to_rcar_lvds(bridge);
> @@ -647,10 +645,9 @@ static void rcar_lvds_detach(struct drm_bridge *bridge)
>  static const struct drm_bridge_funcs rcar_lvds_bridge_ops = {
>  	.attach = rcar_lvds_attach,
>  	.detach = rcar_lvds_detach,
> -	.enable = rcar_lvds_enable,
> -	.disable = rcar_lvds_disable,
> +	.atomic_enable = rcar_lvds_atomic_enable,
> +	.atomic_disable = rcar_lvds_atomic_disable,
>  	.mode_fixup = rcar_lvds_mode_fixup,
> -	.mode_set = rcar_lvds_mode_set,
>  };
> 
>  bool rcar_lvds_dual_link(struct drm_bridge *bridge)
> --
> Regards,
> 
> Laurent Pinchart