[PATCH v3 05/21] drm/bridge: Introduce drm_bridge_chain_get_next_bridge()

[Neil Armstrong]

On 23/10/2019 17:44, Boris Brezillon wrote:
> And use it in drivers accessing the bridge->next field directly.
> This is part of our attempt to make the bridge chain a double-linked list
> based on the generic list helpers.
> 
> Signed-off-by: Boris Brezillon <boris.brezillon at collabora.com>
> ---
> Changes in v3:
> * Inline drm_bridge_chain_get_next_bridge() (Suggested by Laurent)
> 
> Changes in v2:
> * Kill the last/first helpers (they're not really needed)
> * Drop the !bridge || !bridge->encoder test
> ---
>  drivers/gpu/drm/exynos/exynos_drm_dsi.c |  3 ++-
>  drivers/gpu/drm/mediatek/mtk_hdmi.c     |  6 ++++--
>  drivers/gpu/drm/omapdrm/omap_drv.c      |  4 ++--
>  drivers/gpu/drm/omapdrm/omap_encoder.c  |  3 ++-
>  drivers/gpu/drm/vc4/vc4_dsi.c           |  4 +++-
>  include/drm/drm_bridge.h                | 13 +++++++++++++
>  6 files changed, 26 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> index 3915f50b005e..005c67894b78 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> @@ -1593,9 +1593,10 @@ static int exynos_dsi_host_detach(struct mipi_dsi_host *host,
>  				  struct mipi_dsi_device *device)
>  {
>  	struct exynos_dsi *dsi = host_to_dsi(host);
> -	struct drm_bridge *out_bridge = dsi->bridge.next;
>  	struct drm_device *drm = dsi->encoder.dev;
> +	struct drm_bridge *out_bridge;
>  
> +	out_bridge = drm_bridge_chain_get_next_bridge(&dsi->bridge);
>  	if (dsi->panel) {
>  		mutex_lock(&drm->mode_config.mutex);
>  		exynos_dsi_disable(&dsi->bridge);
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index ea68b5adccbe..cfaa5aab8876 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> @@ -1238,16 +1238,18 @@ static int mtk_hdmi_conn_mode_valid(struct drm_connector *conn,
>  				    struct drm_display_mode *mode)
>  {
>  	struct mtk_hdmi *hdmi = hdmi_ctx_from_conn(conn);
> +	struct drm_bridge *next_bridge;
>  
>  	dev_dbg(hdmi->dev, "xres=%d, yres=%d, refresh=%d, intl=%d clock=%d\n",
>  		mode->hdisplay, mode->vdisplay, mode->vrefresh,
>  		!!(mode->flags & DRM_MODE_FLAG_INTERLACE), mode->clock * 1000);
>  
> -	if (hdmi->bridge.next) {
> +	next_bridge = drm_bridge_chain_get_next_bridge(&hdmi->bridge);
> +	if (next_bridge) {
>  		struct drm_display_mode adjusted_mode;
>  
>  		drm_mode_copy(&adjusted_mode, mode);
> -		if (!drm_bridge_chain_mode_fixup(hdmi->bridge.next, mode,
> +		if (!drm_bridge_chain_mode_fixup(next_bridge, mode,
>  						 &adjusted_mode))
>  			return MODE_BAD;
>  	}
> diff --git a/drivers/gpu/drm/omapdrm/omap_drv.c b/drivers/gpu/drm/omapdrm/omap_drv.c
> index b3e22c890c51..865164fe28dc 100644
> --- a/drivers/gpu/drm/omapdrm/omap_drv.c
> +++ b/drivers/gpu/drm/omapdrm/omap_drv.c
> @@ -217,8 +217,8 @@ static int omap_display_id(struct omap_dss_device *output)
>  	} else if (output->bridge) {
>  		struct drm_bridge *bridge = output->bridge;
>  
> -		while (bridge->next)
> -			bridge = bridge->next;
> +		while (drm_bridge_chain_get_next_bridge(bridge))
> +			bridge = drm_bridge_chain_get_next_bridge(bridge);
>  
>  		node = bridge->of_node;
>  	} else if (output->panel) {
> diff --git a/drivers/gpu/drm/omapdrm/omap_encoder.c b/drivers/gpu/drm/omapdrm/omap_encoder.c
> index 24bbe9f2a32e..8ca54081997e 100644
> --- a/drivers/gpu/drm/omapdrm/omap_encoder.c
> +++ b/drivers/gpu/drm/omapdrm/omap_encoder.c
> @@ -126,7 +126,8 @@ static void omap_encoder_mode_set(struct drm_encoder *encoder,
>  	for (dssdev = output; dssdev; dssdev = dssdev->next)
>  		omap_encoder_update_videomode_flags(&vm, dssdev->bus_flags);
>  
> -	for (bridge = output->bridge; bridge; bridge = bridge->next) {
> +	for (bridge = output->bridge; bridge;
> +	     bridge = drm_bridge_chain_get_next_bridge(bridge)) {
>  		if (!bridge->timings)
>  			continue;
>  
> diff --git a/drivers/gpu/drm/vc4/vc4_dsi.c b/drivers/gpu/drm/vc4/vc4_dsi.c
> index 49f8a313e759..49c47185aff0 100644
> --- a/drivers/gpu/drm/vc4/vc4_dsi.c
> +++ b/drivers/gpu/drm/vc4/vc4_dsi.c
> @@ -1644,8 +1644,10 @@ static void vc4_dsi_unbind(struct device *dev, struct device *master,
>  	struct drm_device *drm = dev_get_drvdata(master);
>  	struct vc4_dev *vc4 = to_vc4_dev(drm);
>  	struct vc4_dsi *dsi = dev_get_drvdata(dev);
> +	struct drm_bridge *bridge;
>  
> -	if (dsi->bridge.next)
> +	bridge = drm_bridge_chain_get_next_bridge(&dsi->bridge);
> +	if (bridge)
>  		pm_runtime_disable(dev);
>  
>  	vc4_dsi_encoder_destroy(dsi->encoder);
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index 726435baf4ad..8aeba83fcf31 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -409,6 +409,19 @@ struct drm_bridge *of_drm_find_bridge(struct device_node *np);
>  int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
>  		      struct drm_bridge *previous);
>  
> +/**
> + * drm_bridge_chain_get_next_bridge() - Get the next bridge in the chain
> + * @bridge: bridge object
> + *
> + * RETURNS:
> + * the next bridge in the chain, or NULL if @bridge is the last.
> + */
> +static inline struct drm_bridge *
> +drm_bridge_chain_get_next_bridge(struct drm_bridge *bridge)
> +{
> +	return bridge->next;
> +}
> +
>  bool drm_bridge_chain_mode_fixup(struct drm_bridge *bridge,
>  				 const struct drm_display_mode *mode,
>  				 struct drm_display_mode *adjusted_mode);
> 

Reviewed-by: Neil Armstrong <narmstrong at baylibre.com>