From mboxrd@z Thu Jan  1 00:00:00 1970
From: architt@codeaurora.org (Archit Taneja)
Date: Wed, 28 Jun 2017 10:13:21 +0530
Subject: [PATCH v4 1/6] drm/stm: ltdc: Add panel-bridge support
In-Reply-To: <1497889685-27349-2-git-send-email-philippe.cornu@st.com>
References: <1497889685-27349-1-git-send-email-philippe.cornu@st.com>
 <1497889685-27349-2-git-send-email-philippe.cornu@st.com>
Message-ID: <250841cc-75ec-0cab-ef54-c0152aa78f04@codeaurora.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org



On 06/19/2017 09:58 PM, Philippe CORNU wrote:
> Add the panel-bridge support for both panels & bridges (used by DSI host &
> HDMI/LVDS bridges).

Reviewed-by: Archit Taneja <architt@codeaurora.org>

> 
> Signed-off-by: Philippe CORNU <philippe.cornu@st.com>
> ---
>   drivers/gpu/drm/stm/Kconfig |   2 +-
>   drivers/gpu/drm/stm/ltdc.c  | 211 ++++++++------------------------------------
>   drivers/gpu/drm/stm/ltdc.h  |   3 +-
>   3 files changed, 38 insertions(+), 178 deletions(-)
> 
> diff --git a/drivers/gpu/drm/stm/Kconfig b/drivers/gpu/drm/stm/Kconfig
> index 2c4817f..4b88223 100644
> --- a/drivers/gpu/drm/stm/Kconfig
> +++ b/drivers/gpu/drm/stm/Kconfig
> @@ -4,7 +4,7 @@ config DRM_STM
>   	select DRM_KMS_HELPER
>   	select DRM_GEM_CMA_HELPER
>   	select DRM_KMS_CMA_HELPER
> -	select DRM_PANEL
> +	select DRM_PANEL_BRIDGE
>   	select VIDEOMODE_HELPERS
>   	select FB_PROVIDE_GET_FB_UNMAPPED_AREA
>   	default y
> diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
> index 1b9483d..8aa0586 100644
> --- a/drivers/gpu/drm/stm/ltdc.c
> +++ b/drivers/gpu/drm/stm/ltdc.c
> @@ -21,7 +21,7 @@
>   #include <drm/drm_fb_cma_helper.h>
>   #include <drm/drm_gem_cma_helper.h>
>   #include <drm/drm_of.h>
> -#include <drm/drm_panel.h>
> +#include <drm/drm_bridge.h>
>   #include <drm/drm_plane_helper.h>
>   
>   #include <video/videomode.h>
> @@ -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;
> @@ -813,130 +808,35 @@ static int ltdc_crtc_init(struct drm_device *ddev, struct drm_crtc *crtc)
>    * DRM_ENCODER
>    */
>   
> -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 = {
> -	.enable = ltdc_rgb_encoder_enable,
> -	.disable = ltdc_rgb_encoder_disable,
> -};
> -
> -static const struct drm_encoder_funcs ltdc_rgb_encoder_funcs = {
> +static const struct drm_encoder_funcs ltdc_encoder_funcs = {
>   	.destroy = drm_encoder_cleanup,
>   };
>   
> -static struct drm_encoder *ltdc_rgb_encoder_create(struct drm_device *ddev)
> +static int ltdc_encoder_init(struct drm_device *ddev)
>   {
> +	struct ltdc_device *ldev = ddev->dev_private;
>   	struct drm_encoder *encoder;
> +	int ret;
>   
>   	encoder = devm_kzalloc(ddev->dev, sizeof(*encoder), GFP_KERNEL);
>   	if (!encoder)
> -		return NULL;
> +		return -ENOMEM;
>   
>   	encoder->possible_crtcs = CRTC_MASK;
>   	encoder->possible_clones = 0; /* No cloning support */
>   
> -	drm_encoder_init(ddev, encoder, &ltdc_rgb_encoder_funcs,
> +	drm_encoder_init(ddev, encoder, &ltdc_encoder_funcs,
>   			 DRM_MODE_ENCODER_DPI, NULL);
>   
> -	drm_encoder_helper_add(encoder, &ltdc_rgb_encoder_helper_funcs);
> -
> -	DRM_DEBUG_DRIVER("RGB encoder:%d created\n", encoder->base.id);
> -
> -	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;
> +	ret = drm_bridge_attach(encoder, ldev->bridge, NULL);
> +	if (ret) {
> +		drm_encoder_cleanup(encoder);
> +		return -EINVAL;
>   	}
>   
> -	drm_connector_helper_add(connector, &ltdc_rgb_connector_helper_funcs);
> -
> -	DRM_DEBUG_DRIVER("RGB connector:%d created\n", connector->base.id);
> +	DRM_DEBUG_DRIVER("Bridge encoder:%d created\n", encoder->base.id);
>   
> -	return connector;
> +	return 0;
>   }
>   
>   static int ltdc_get_caps(struct drm_device *ddev)
> @@ -972,49 +872,14 @@ static int ltdc_get_caps(struct drm_device *ddev)
>   	return 0;
>   }
>   
> -static struct drm_panel *ltdc_get_panel(struct drm_device *ddev)
> -{
> -	struct device *dev = ddev->dev;
> -	struct device_node *np = dev->of_node;
> -	struct device_node *entity, *port = NULL;
> -	struct drm_panel *panel = NULL;
> -
> -	DRM_DEBUG_DRIVER("\n");
> -
> -	/*
> -	 * Parse ltdc node to get remote port and find RGB panel / HDMI slave
> -	 * If a dsi or a bridge (hdmi, lvds...) is connected to ltdc,
> -	 * a remote port & RGB panel will not be found.
> -	 */
> -	for_each_endpoint_of_node(np, entity) {
> -		if (!of_device_is_available(entity))
> -			continue;
> -
> -		port = of_graph_get_remote_port_parent(entity);
> -		if (port) {
> -			panel = of_drm_find_panel(port);
> -			of_node_put(port);
> -			if (panel) {
> -				DRM_DEBUG_DRIVER("remote panel %s\n",
> -						 port->full_name);
> -			} else {
> -				DRM_DEBUG_DRIVER("panel missing\n");
> -				of_node_put(entity);
> -			}
> -		}
> -	}
> -
> -	return panel;
> -}
> -
>   int ltdc_load(struct drm_device *ddev)
>   {
>   	struct platform_device *pdev = to_platform_device(ddev->dev);
>   	struct ltdc_device *ldev = ddev->dev_private;
>   	struct device *dev = ddev->dev;
>   	struct device_node *np = dev->of_node;
> -	struct drm_encoder *encoder;
> -	struct drm_connector *connector = NULL;
> +	struct drm_bridge *bridge;
> +	struct drm_panel *panel;
>   	struct drm_crtc *crtc;
>   	struct reset_control *rstc;
>   	struct resource res;
> @@ -1022,9 +887,9 @@ int ltdc_load(struct drm_device *ddev)
>   
>   	DRM_DEBUG_DRIVER("\n");
>   
> -	ldev->panel = ltdc_get_panel(ddev);
> -	if (!ldev->panel)
> -		return -EPROBE_DEFER;
> +	ret = drm_of_find_panel_or_bridge(np, 0, 0, &panel, &bridge);
> +	if (ret)
> +		return ret;
>   
>   	rstc = of_reset_control_get(np, NULL);
>   
> @@ -1082,28 +947,21 @@ int ltdc_load(struct drm_device *ddev)
>   
>   	DRM_INFO("ltdc hw version 0x%08x - ready\n", ldev->caps.hw_version);
>   
> -	if (ldev->panel) {
> -		encoder = ltdc_rgb_encoder_create(ddev);
> -		if (!encoder) {
> -			DRM_ERROR("Failed to create RGB encoder\n");
> -			ret = -EINVAL;
> -			goto err;
> +	if (panel) {
> +		bridge = drm_panel_bridge_add(panel, DRM_MODE_CONNECTOR_DPI);
> +		if (IS_ERR(bridge)) {
> +			DRM_ERROR("Failed to create panel-bridge\n");
> +			return PTR_ERR(bridge);
>   		}
> +		ldev->is_panel_bridge = true;
> +	}
>   
> -		connector = ltdc_rgb_connector_create(ddev);
> -		if (!connector) {
> -			DRM_ERROR("Failed to create RGB connector\n");
> -			ret = -EINVAL;
> -			goto err;
> -		}
> +	ldev->bridge = bridge;
>   
> -		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);
> +	ret = ltdc_encoder_init(ddev);
> +	if (ret) {
> +		DRM_ERROR("Failed to init encoder\n");
> +		goto err;
>   	}
>   
>   	crtc = devm_kzalloc(dev, sizeof(*crtc), GFP_KERNEL);
> @@ -1129,9 +987,10 @@ int ltdc_load(struct drm_device *ddev)
>   	ddev->irq_enabled = 1;
>   
>   	return 0;
> +
>   err:
> -	if (ldev->panel)
> -		drm_panel_detach(ldev->panel);
> +	if (ldev->is_panel_bridge)
> +		drm_panel_bridge_remove(bridge);
>   
>   	clk_disable_unprepare(ldev->pixel_clk);
>   
> @@ -1144,8 +1003,8 @@ void ltdc_unload(struct drm_device *ddev)
>   
>   	DRM_DEBUG_DRIVER("\n");
>   
> -	if (ldev->panel)
> -		drm_panel_detach(ldev->panel);
> +	if (ldev->is_panel_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 d7a9c73..d9e899d 100644
> --- a/drivers/gpu/drm/stm/ltdc.h
> +++ b/drivers/gpu/drm/stm/ltdc.h
> @@ -24,7 +24,8 @@ 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;
> +	bool is_panel_bridge;
>   	struct mutex err_lock;	/* protecting error_status */
>   	struct ltdc_caps caps;
>   	u32 clut[256];		/* color look up table */
> 

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