Re: [PATCH v2 4/7] drm/mediatek: Use the panel-bridge helper.

[Boris Brezillon]

On Thu, 11 May 2017 11:31:25 -0700
Eric Anholt <eric@xxxxxxxxxx> wrote:

> Avoids a bunch of connector boilerplate.  Note that this causes panel
> prepare() to be moved before mtk_dsi_poweron() and unprepare() to be
> after poweroff().  I think this is the expected usage of the panel API
> (enable should be when you do things that require the link to be
> brought up), but there may be issues here.
> 
> Signed-off-by: Eric Anholt <eric@xxxxxxxxxx>

Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>

> ---
> 
> Note that I haven't tested this change, and am not committed to this
> patch.  It's just an optional cleanup, if it works for you.
> 
>  drivers/gpu/drm/mediatek/mtk_dsi.c | 125 ++++---------------------------------
>  1 file changed, 13 insertions(+), 112 deletions(-)
> 
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 808b995a990f..764bd8b9c256 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -160,7 +160,6 @@ struct mtk_dsi {
>  	struct device *dev;
>  	struct mipi_dsi_host host;
>  	struct drm_encoder encoder;
> -	struct drm_connector conn;
>  	struct drm_panel *panel;
>  	struct drm_bridge *bridge;
>  	struct phy *phy;
> @@ -188,11 +187,6 @@ static inline struct mtk_dsi *encoder_to_dsi(struct drm_encoder *e)
>  	return container_of(e, struct mtk_dsi, encoder);
>  }
>  
> -static inline struct mtk_dsi *connector_to_dsi(struct drm_connector *c)
> -{
> -	return container_of(c, struct mtk_dsi, conn);
> -}
> -
>  static inline struct mtk_dsi *host_to_dsi(struct mipi_dsi_host *h)
>  {
>  	return container_of(h, struct mtk_dsi, host);
> @@ -603,16 +597,7 @@ static int mtk_dsi_poweron(struct mtk_dsi *dsi)
>  	mtk_dsi_lane0_ulp_mode_leave(dsi);
>  	mtk_dsi_clk_hs_mode(dsi, 0);
>  
> -	if (dsi->panel) {
> -		if (drm_panel_prepare(dsi->panel)) {
> -			DRM_ERROR("failed to prepare the panel\n");
> -			goto err_disable_digital_clk;
> -		}
> -	}
> -
>  	return 0;
> -err_disable_digital_clk:
> -	clk_disable_unprepare(dsi->digital_clk);
>  err_disable_engine_clk:
>  	clk_disable_unprepare(dsi->engine_clk);
>  err_phy_power_off:
> @@ -630,15 +615,7 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi)
>  	if (--dsi->refcount != 0)
>  		return;
>  
> -	if (!mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500)) {
> -		if (dsi->panel) {
> -			if (drm_panel_unprepare(dsi->panel)) {
> -				DRM_ERROR("failed to unprepare the panel\n");
> -				return;
> -			}
> -		}
> -	}
> -
> +	mtk_dsi_switch_to_cmd_mode(dsi, VM_DONE_INT_FLAG, 500);
>  	mtk_dsi_reset_engine(dsi);
>  	mtk_dsi_lane0_ulp_mode_enter(dsi);
>  	mtk_dsi_clk_ulp_mode_enter(dsi);
> @@ -669,19 +646,9 @@ static void mtk_output_dsi_enable(struct mtk_dsi *dsi)
>  
>  	mtk_dsi_start(dsi);
>  
> -	if (dsi->panel) {
> -		if (drm_panel_enable(dsi->panel)) {
> -			DRM_ERROR("failed to enable the panel\n");
> -			goto err_dsi_power_off;
> -		}
> -	}
> -
>  	dsi->enabled = true;
>  
>  	return;
> -err_dsi_power_off:
> -	mtk_dsi_stop(dsi);
> -	mtk_dsi_poweroff(dsi);
>  }
>  
>  static void mtk_output_dsi_disable(struct mtk_dsi *dsi)
> @@ -689,13 +656,6 @@ static void mtk_output_dsi_disable(struct mtk_dsi *dsi)
>  	if (!dsi->enabled)
>  		return;
>  
> -	if (dsi->panel) {
> -		if (drm_panel_disable(dsi->panel)) {
> -			DRM_ERROR("failed to disable the panel\n");
> -			return;
> -		}
> -	}
> -
>  	mtk_dsi_stop(dsi);
>  	mtk_dsi_poweroff(dsi);
>  
> @@ -750,13 +710,6 @@ static void mtk_dsi_encoder_enable(struct drm_encoder *encoder)
>  	mtk_output_dsi_enable(dsi);
>  }
>  
> -static int mtk_dsi_connector_get_modes(struct drm_connector *connector)
> -{
> -	struct mtk_dsi *dsi = connector_to_dsi(connector);
> -
> -	return drm_panel_get_modes(dsi->panel);
> -}
> -
>  static const struct drm_encoder_helper_funcs mtk_dsi_encoder_helper_funcs = {
>  	.mode_fixup = mtk_dsi_encoder_mode_fixup,
>  	.mode_set = mtk_dsi_encoder_mode_set,
> @@ -764,52 +717,7 @@ static const struct drm_encoder_helper_funcs mtk_dsi_encoder_helper_funcs = {
>  	.enable = mtk_dsi_encoder_enable,
>  };
>  
> -static const struct drm_connector_funcs mtk_dsi_connector_funcs = {
> -	.dpms = drm_atomic_helper_connector_dpms,
> -	.fill_modes = drm_helper_probe_single_connector_modes,
> -	.destroy = drm_connector_cleanup,
> -	.reset = drm_atomic_helper_connector_reset,
> -	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> -	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> -};
> -
> -static const struct drm_connector_helper_funcs
> -	mtk_dsi_connector_helper_funcs = {
> -	.get_modes = mtk_dsi_connector_get_modes,
> -};
> -
> -static int mtk_dsi_create_connector(struct drm_device *drm, struct mtk_dsi *dsi)
> -{
> -	int ret;
> -
> -	ret = drm_connector_init(drm, &dsi->conn, &mtk_dsi_connector_funcs,
> -				 DRM_MODE_CONNECTOR_DSI);
> -	if (ret) {
> -		DRM_ERROR("Failed to connector init to drm\n");
> -		return ret;
> -	}
> -
> -	drm_connector_helper_add(&dsi->conn, &mtk_dsi_connector_helper_funcs);
> -
> -	dsi->conn.dpms = DRM_MODE_DPMS_OFF;
> -	drm_mode_connector_attach_encoder(&dsi->conn, &dsi->encoder);
> -
> -	if (dsi->panel) {
> -		ret = drm_panel_attach(dsi->panel, &dsi->conn);
> -		if (ret) {
> -			DRM_ERROR("Failed to attach panel to drm\n");
> -			goto err_connector_cleanup;
> -		}
> -	}
> -
> -	return 0;
> -
> -err_connector_cleanup:
> -	drm_connector_cleanup(&dsi->conn);
> -	return ret;
> -}
> -
> -static int mtk_dsi_create_conn_enc(struct drm_device *drm, struct mtk_dsi *dsi)
> +static int mtk_dsi_create_enc(struct drm_device *drm, struct mtk_dsi *dsi)
>  {
>  	int ret;
>  
> @@ -827,15 +735,10 @@ static int mtk_dsi_create_conn_enc(struct drm_device *drm, struct mtk_dsi *dsi)
>  	 */
>  	dsi->encoder.possible_crtcs = 1;
>  
> -	/* If there's a bridge, attach to it and let it create the connector */
>  	ret = drm_bridge_attach(&dsi->encoder, dsi->bridge, NULL);
>  	if (ret) {
>  		DRM_ERROR("Failed to attach bridge to drm\n");
> -
> -		/* Otherwise create our own connector and attach to a panel */
> -		ret = mtk_dsi_create_connector(drm, dsi);
> -		if (ret)
> -			goto err_encoder_cleanup;
> +		goto err_encoder_cleanup;
>  	}
>  
>  	return 0;
> @@ -848,9 +751,8 @@ static int mtk_dsi_create_conn_enc(struct drm_device *drm, struct mtk_dsi *dsi)
>  static void mtk_dsi_destroy_conn_enc(struct mtk_dsi *dsi)
>  {
>  	drm_encoder_cleanup(&dsi->encoder);
> -	/* Skip connector cleanup if creation was delegated to the bridge */
> -	if (dsi->conn.dev)
> -		drm_connector_cleanup(&dsi->conn);
> +	if (dsi->panel)
> +		drm_panel_bridge_remove(dsi->bridge);
>  }
>  
>  static void mtk_dsi_ddp_start(struct mtk_ddp_comp *comp)
> @@ -881,20 +783,12 @@ static int mtk_dsi_host_attach(struct mipi_dsi_host *host,
>  	dsi->format = device->format;
>  	dsi->mode_flags = device->mode_flags;
>  
> -	if (dsi->conn.dev)
> -		drm_helper_hpd_irq_event(dsi->conn.dev);
> -
>  	return 0;
>  }
>  
>  static int mtk_dsi_host_detach(struct mipi_dsi_host *host,
>  			       struct mipi_dsi_device *device)
>  {
> -	struct mtk_dsi *dsi = host_to_dsi(host);
> -
> -	if (dsi->conn.dev)
> -		drm_helper_hpd_irq_event(dsi->conn.dev);
> -
>  	return 0;
>  }
>  
> @@ -1062,7 +956,7 @@ static int mtk_dsi_bind(struct device *dev, struct device *master, void *data)
>  		goto err_ddp_comp_unregister;
>  	}
>  
> -	ret = mtk_dsi_create_conn_enc(drm, dsi);
> +	ret = mtk_dsi_create_enc(drm, dsi);
>  	if (ret) {
>  		DRM_ERROR("Encoder create failed with %d\n", ret);
>  		goto err_unregister;
> @@ -1114,6 +1008,13 @@ static int mtk_dsi_probe(struct platform_device *pdev)
>  	if (ret)
>  		return ret;
>  
> +	if (dsi->panel) {
> +		dsi->bridge = drm_panel_bridge_add(dsi->panel,
> +						   DRM_MODE_CONNECTOR_DSI);
> +		if (IS_ERR(dsi->bridge))
> +			return PTR_ERR(dsi->bridge);
> +	}
> +
>  	dsi->engine_clk = devm_clk_get(dev, "engine");
>  	if (IS_ERR(dsi->engine_clk)) {
>  		ret = PTR_ERR(dsi->engine_clk);