[PATCH v2 5/7] drm/ltdc: Use the panel-bridge helper.

Philippe CORNU philippe.cornu at st.com
Tue May 30 16:55:42 UTC 2017


Hi Eric,

I took your patch for the panel-bridge and it works perfectly in both 
DPI mode (panel RGB //) and DSI mode (bridge dw mipi dsi), bravo :-)

~160 lines have been removed from ltdc.c thanks to your panel-bridge code!

Many thanks
Philippe

On 05/11/2017 08:31 PM, Eric Anholt wrote:
> Another 100 lines of boilerplate gone.  Bridges aren't supported yet,
> but will be trivial to add later.
> 
> Signed-off-by: Eric Anholt <eric at anholt.net>
> ---
> 
> Also untested.
> 
>   drivers/gpu/drm/stm/ltdc.c | 128 +++++----------------------------------------
>   drivers/gpu/drm/stm/ltdc.h |   2 +-
>   2 files changed, 13 insertions(+), 117 deletions(-)
> 
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index a40418cda74a..41a1c5d68f5b 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -269,11 +269,6 @@ static inline struct ltdc_device *encoder_to_ltdc(struct drm_encoder *enc)
>   	return (struct ltdc_device *)enc->dev->dev_private;
>   }
>   
> -static inline struct ltdc_device *connector_to_ltdc(struct drm_connector *con)
> -{
> -	return (struct ltdc_device *)con->dev->dev_private;
> -}
> -
>   static inline enum ltdc_pix_fmt to_ltdc_pixelformat(u32 drm_fmt)
>   {
>   	enum ltdc_pix_fmt pf;
> @@ -815,22 +810,12 @@ static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
>   
>   static void ltdc_rgb_encoder_enable(struct drm_encoder *encoder)
>   {
> -	struct ltdc_device *ldev = encoder_to_ltdc(encoder);
> -
>   	DRM_DEBUG_DRIVER("\n");
> -
> -	drm_panel_prepare(ldev->panel);
> -	drm_panel_enable(ldev->panel);
>   }
>   
>   static void ltdc_rgb_encoder_disable(struct drm_encoder *encoder)
>   {
> -	struct ltdc_device *ldev = encoder_to_ltdc(encoder);
> -
>   	DRM_DEBUG_DRIVER("\n");
> -
> -	drm_panel_disable(ldev->panel);
> -	drm_panel_unprepare(ldev->panel);
>   }
>   
>   static const struct drm_encoder_helper_funcs ltdc_rgb_encoder_helper_funcs = {
> @@ -863,82 +848,6 @@ static struct drm_encoder *ltdc_rgb_encoder_create(struct drm_device *ddev)
>   	return encoder;
>   }
>   
> -/*
> - * DRM_CONNECTOR
> - */
> -
> -static int ltdc_rgb_connector_get_modes(struct drm_connector *connector)
> -{
> -	struct drm_device *ddev = connector->dev;
> -	struct ltdc_device *ldev = ddev->dev_private;
> -	int ret = 0;
> -
> -	DRM_DEBUG_DRIVER("\n");
> -
> -	if (ldev->panel)
> -		ret = drm_panel_get_modes(ldev->panel);
> -
> -	return ret < 0 ? 0 : ret;
> -}
> -
> -static struct drm_connector_helper_funcs ltdc_rgb_connector_helper_funcs = {
> -	.get_modes = ltdc_rgb_connector_get_modes,
> -};
> -
> -static enum drm_connector_status
> -ltdc_rgb_connector_detect(struct drm_connector *connector, bool force)
> -{
> -	struct ltdc_device *ldev = connector_to_ltdc(connector);
> -
> -	return ldev->panel ? connector_status_connected :
> -	       connector_status_disconnected;
> -}
> -
> -static void ltdc_rgb_connector_destroy(struct drm_connector *connector)
> -{
> -	DRM_DEBUG_DRIVER("\n");
> -
> -	drm_connector_unregister(connector);
> -	drm_connector_cleanup(connector);
> -}
> -
> -static const struct drm_connector_funcs ltdc_rgb_connector_funcs = {
> -	.dpms = drm_atomic_helper_connector_dpms,
> -	.fill_modes = drm_helper_probe_single_connector_modes,
> -	.detect = ltdc_rgb_connector_detect,
> -	.destroy = ltdc_rgb_connector_destroy,
> -	.reset = drm_atomic_helper_connector_reset,
> -	.atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> -	.atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> -};
> -
> -struct drm_connector *ltdc_rgb_connector_create(struct drm_device *ddev)
> -{
> -	struct drm_connector *connector;
> -	int err;
> -
> -	connector = devm_kzalloc(ddev->dev, sizeof(*connector), GFP_KERNEL);
> -	if (!connector) {
> -		DRM_ERROR("Failed to allocate connector\n");
> -		return NULL;
> -	}
> -
> -	connector->polled = DRM_CONNECTOR_POLL_HPD;
> -
> -	err = drm_connector_init(ddev, connector, &ltdc_rgb_connector_funcs,
> -				 DRM_MODE_CONNECTOR_DPI);
> -	if (err) {
> -		DRM_ERROR("Failed to initialize connector\n");
> -		return NULL;
> -	}
> -
> -	drm_connector_helper_add(connector, &ltdc_rgb_connector_helper_funcs);
> -
> -	DRM_DEBUG_DRIVER("RGB connector:%d created\n", connector->base.id);
> -
> -	return connector;
> -}
> -
>   static int ltdc_get_caps(struct drm_device *ddev)
>   {
>   	struct ltdc_device *ldev = ddev->dev_private;
> @@ -972,7 +881,7 @@ static int ltdc_get_caps(struct drm_device *ddev)
>   	return 0;
>   }
>   
> -static struct drm_panel *ltdc_get_panel(struct drm_device *ddev)
> +static struct drm_bridge *ltdc_get_bridge(struct drm_device *ddev)
>   {
>   	struct device *dev = ddev->dev;
>   	struct device_node *np = dev->of_node;
> @@ -1004,7 +913,10 @@ static struct drm_panel *ltdc_get_panel(struct drm_device *ddev)
>   		}
>   	}
>   
> -	return panel;
> +	if (!panel)
> +		return ERR_PTR(-ENODEV);
> +
> +	return drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DPI);
>   }
>   
>   int ltdc_load(struct drm_device *ddev)
> @@ -1014,7 +926,6 @@ int ltdc_load(struct drm_device *ddev)
>   	struct device *dev = ddev->dev;
>   	struct device_node *np = dev->of_node;
>   	struct drm_encoder *encoder;
> -	struct drm_connector *connector = NULL;
>   	struct drm_crtc *crtc;
>   	struct reset_control *rstc;
>   	struct resource res;
> @@ -1022,8 +933,8 @@ int ltdc_load(struct drm_device *ddev)
>   
>   	DRM_DEBUG_DRIVER("\n");
>   
> -	ldev->panel = ltdc_get_panel(ddev);
> -	if (!ldev->panel)
> +	ldev->bridge = ltdc_get_bridge(ddev);
> +	if (!ldev->bridge)
>   		return -EPROBE_DEFER;
>   
>   	rstc = of_reset_control_get(np, NULL);
> @@ -1082,28 +993,13 @@ int ltdc_load(struct drm_device *ddev)
>   
>   	DRM_INFO("ltdc hw version 0x%08x - ready\n", ldev->caps.hw_version);
>   
> -	if (ldev->panel) {
> +	if (ldev->bridge) {
>   		encoder = ltdc_rgb_encoder_create(ddev);
>   		if (!encoder) {
>   			DRM_ERROR("Failed to create RGB encoder\n");
>   			ret = -EINVAL;
>   			goto err;
>   		}
> -
> -		connector = ltdc_rgb_connector_create(ddev);
> -		if (!connector) {
> -			DRM_ERROR("Failed to create RGB connector\n");
> -			ret = -EINVAL;
> -			goto err;
> -		}
> -
> -		ret = drm_mode_connector_attach_encoder(connector, encoder);
> -		if (ret) {
> -			DRM_ERROR("Failed to attach connector to encoder\n");
> -			goto err;
> -		}
> -
> -		drm_panel_attach(ldev->panel, connector);
>   	}
>   
>   	crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
> @@ -1130,8 +1026,8 @@ int ltdc_load(struct drm_device *ddev)
>   
>   	return 0;
>   err:
> -	if (ldev->panel)
> -		drm_panel_detach(ldev->panel);
> +	if (ldev->bridge)
> +		drm_panel_bridge_remove(ldev->bridge);
>   
>   	clk_disable_unprepare(ldev->pixel_clk);
>   
> @@ -1146,8 +1042,8 @@ void ltdc_unload(struct drm_device *ddev)
>   
>   	drm_vblank_cleanup(ddev);
>   
> -	if (ldev->panel)
> -		drm_panel_detach(ldev->panel);
> +	if (ldev->bridge)
> +		drm_panel_bridge_remove(ldev->bridge);
>   
>   	clk_disable_unprepare(ldev->pixel_clk);
>   }
> diff --git a/drivers/gpu/drm/stm/ltdc.h b/drivers/gpu/drm/stm/ltdc.h
> index d7a9c736ac1e..d78cb0dd3200 100644
> --- a/drivers/gpu/drm/stm/ltdc.h
> +++ b/drivers/gpu/drm/stm/ltdc.h
> @@ -24,7 +24,7 @@ struct ltdc_device {
>   	struct drm_fbdev_cma *fbdev;
>   	void __iomem *regs;
>   	struct clk *pixel_clk;	/* lcd pixel clock */
> -	struct drm_panel *panel;
> +	struct drm_bridge *bridge;
>   	struct mutex err_lock;	/* protecting error_status */
>   	struct ltdc_caps caps;
>   	u32 clut[256];		/* color look up table */
> 


More information about the dri-devel mailing list