On Tue, 29 Nov 2016 11:04:33 +0200
Laurent Pinchart <laurent.pinchart+rene...@ideasonboard.com> wrote:
> Instead of linking encoders and bridges in every driver (and getting it
> wrong half of the time, as many drivers forget to set the drm_bridge
> encoder pointer), do so in core code. The drm_bridge_attach() function
> needs the encoder and optional previous bridge to perform that task,
> update all the callers.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+rene...@ideasonboard.com>
> ---
> drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c | 4 +-
For atmel-hlcdc
Acked-by: Boris Brezillon <boris.brezil...@free-electrons.com>
> drivers/gpu/drm/bridge/analogix/analogix_dp_core.c | 4 +-
> drivers/gpu/drm/bridge/dw-hdmi.c | 3 +-
> drivers/gpu/drm/drm_bridge.c | 46
> ++++++++++++++++------
> drivers/gpu/drm/drm_simple_kms_helper.c | 4 +-
> drivers/gpu/drm/exynos/exynos_dp.c | 5 +--
> drivers/gpu/drm/exynos/exynos_drm_dsi.c | 6 +--
> drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c | 5 +--
> drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c | 5 +--
> drivers/gpu/drm/imx/imx-ldb.c | 6 +--
> drivers/gpu/drm/imx/parallel-display.c | 4 +-
> drivers/gpu/drm/mediatek/mtk_dpi.c | 8 ++--
> drivers/gpu/drm/mediatek/mtk_dsi.c | 24 ++---------
> drivers/gpu/drm/mediatek/mtk_hdmi.c | 11 +++---
> drivers/gpu/drm/msm/dsi/dsi_manager.c | 17 +++++---
> drivers/gpu/drm/msm/edp/edp_bridge.c | 2 +-
> drivers/gpu/drm/msm/hdmi/hdmi_bridge.c | 2 +-
> drivers/gpu/drm/rcar-du/rcar_du_hdmienc.c | 5 +--
> drivers/gpu/drm/sti/sti_dvo.c | 3 +-
> drivers/gpu/drm/sti/sti_hda.c | 3 +-
> drivers/gpu/drm/sti/sti_hdmi.c | 3 +-
> drivers/gpu/drm/sun4i/sun4i_rgb.c | 13 +++---
> include/drm/drm_bridge.h | 3 +-
> 23 files changed, 83 insertions(+), 103 deletions(-)
>
> diff --git a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c
> b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c
> index 6119b5085501..e7799b6ee829 100644
> --- a/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c
> +++ b/drivers/gpu/drm/atmel-hlcdc/atmel_hlcdc_output.c
> @@ -230,9 +230,7 @@ static int atmel_hlcdc_attach_endpoint(struct drm_device
> *dev,
> of_node_put(np);
>
> if (bridge) {
> - output->encoder.bridge = bridge;
> - bridge->encoder = &output->encoder;
> - ret = drm_bridge_attach(dev, bridge);
> + ret = drm_bridge_attach(&output->encoder, bridge, NULL);
> if (!ret)
> return 0;
> }
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> index 6e0447f329a2..1835f1fdad19 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
> @@ -1227,12 +1227,10 @@ static int analogix_dp_create_bridge(struct
> drm_device *drm_dev,
>
> dp->bridge = bridge;
>
> - dp->encoder->bridge = bridge;
> bridge->driver_private = dp;
> - bridge->encoder = dp->encoder;
> bridge->funcs = &analogix_dp_bridge_funcs;
>
> - ret = drm_bridge_attach(drm_dev, bridge);
> + ret = drm_bridge_attach(dp->encoder, bridge, NULL);
> if (ret) {
> DRM_ERROR("failed to attach drm bridge\n");
> return -EINVAL;
> diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c
> b/drivers/gpu/drm/bridge/dw-hdmi.c
> index b71088dab268..432e0e3fff72 100644
> --- a/drivers/gpu/drm/bridge/dw-hdmi.c
> +++ b/drivers/gpu/drm/bridge/dw-hdmi.c
> @@ -1841,13 +1841,12 @@ static int dw_hdmi_register(struct drm_device *drm,
> struct dw_hdmi *hdmi)
> hdmi->bridge = bridge;
> bridge->driver_private = hdmi;
> bridge->funcs = &dw_hdmi_bridge_funcs;
> - ret = drm_bridge_attach(drm, bridge);
> + ret = drm_bridge_attach(encoder, bridge, NULL);
> if (ret) {
> DRM_ERROR("Failed to initialize bridge with drm\n");
> return -EINVAL;
> }
>
> - encoder->bridge = bridge;
> hdmi->connector.polled = DRM_CONNECTOR_POLL_HPD;
>
> drm_connector_helper_add(&hdmi->connector,
> diff --git a/drivers/gpu/drm/drm_bridge.c b/drivers/gpu/drm/drm_bridge.c
> index 0ee052b7c21a..850bd6509ef1 100644
> --- a/drivers/gpu/drm/drm_bridge.c
> +++ b/drivers/gpu/drm/drm_bridge.c
> @@ -26,6 +26,7 @@
> #include <linux/mutex.h>
>
> #include <drm/drm_bridge.h>
> +#include <drm/drm_encoder.h>
>
> /**
> * DOC: overview
> @@ -92,32 +93,53 @@ void drm_bridge_remove(struct drm_bridge *bridge)
> EXPORT_SYMBOL(drm_bridge_remove);
>
> /**
> - * drm_bridge_attach - associate given bridge to our DRM device
> + * drm_bridge_attach - attach the bridge to an encoder's chain
> *
> - * @dev: DRM device
> - * @bridge: bridge control structure
> + * @encoder: DRM encoder
> + * @bridge: bridge to attach
> + * @previous: previous bridge in the chain (optional)
> *
> - * Called by a kms driver to link one of our encoder/bridge to the given
> - * bridge.
> + * Called by a kms driver to link the bridge to an encoder's chain. The
> previous
> + * argument specifies the previous bridge in the chain. If NULL, the bridge
> is
> + * linked directly at the encoder's output. Otherwise it is linked at the
> + * previous bridge's output.
> *
> - * Note that setting up links between the bridge and our encoder/bridge
> - * objects needs to be handled by the kms driver itself.
> + * If non-NULL the previous bridge must be already attached by a call to this
> + * function.
> *
> * RETURNS:
> * Zero on success, error code on failure
> */
> -int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge)
> +int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
> + struct drm_bridge *previous)
> {
> - if (!dev || !bridge)
> + int ret;
> +
> + if (!encoder || !bridge)
> + return -EINVAL;
> +
> + if (previous && (!previous->dev || previous->encoder != encoder))
> return -EINVAL;
>
> if (bridge->dev)
> return -EBUSY;
>
> - bridge->dev = dev;
> + bridge->dev = encoder->dev;
> + bridge->encoder = encoder;
> +
> + if (bridge->funcs->attach) {
> + ret = bridge->funcs->attach(bridge);
> + if (ret < 0) {
> + bridge->dev = NULL;
> + bridge->encoder = NULL;
> + return ret;
> + }
> + }
>
> - if (bridge->funcs->attach)
> - return bridge->funcs->attach(bridge);
> + if (previous)
> + previous->next = bridge;
> + else
> + encoder->bridge = bridge;
>
> return 0;
> }
> diff --git a/drivers/gpu/drm/drm_simple_kms_helper.c
> b/drivers/gpu/drm/drm_simple_kms_helper.c
> index 7bae08c2bf0a..ba7be6169339 100644
> --- a/drivers/gpu/drm/drm_simple_kms_helper.c
> +++ b/drivers/gpu/drm/drm_simple_kms_helper.c
> @@ -182,9 +182,7 @@ static const struct drm_plane_funcs
> drm_simple_kms_plane_funcs = {
> int drm_simple_display_pipe_attach_bridge(struct drm_simple_display_pipe
> *pipe,
> struct drm_bridge *bridge)
> {
> - bridge->encoder = &pipe->encoder;
> - pipe->encoder.bridge = bridge;
> - return drm_bridge_attach(pipe->encoder.dev, bridge);
> + return drm_bridge_attach(&pipe->encoder, bridge, NULL);
> }
> EXPORT_SYMBOL(drm_simple_display_pipe_attach_bridge);
>
> diff --git a/drivers/gpu/drm/exynos/exynos_dp.c
> b/drivers/gpu/drm/exynos/exynos_dp.c
> index 528229faffe4..1ef0be338b85 100644
> --- a/drivers/gpu/drm/exynos/exynos_dp.c
> +++ b/drivers/gpu/drm/exynos/exynos_dp.c
> @@ -99,7 +99,6 @@ static int exynos_dp_bridge_attach(struct
> analogix_dp_plat_data *plat_data,
> struct drm_connector *connector)
> {
> struct exynos_dp_device *dp = to_dp(plat_data);
> - struct drm_encoder *encoder = &dp->encoder;
> int ret;
>
> drm_connector_register(connector);
> @@ -107,9 +106,7 @@ static int exynos_dp_bridge_attach(struct
> analogix_dp_plat_data *plat_data,
>
> /* Pre-empt DP connector creation if there's a bridge */
> if (dp->ptn_bridge) {
> - bridge->next = dp->ptn_bridge;
> - dp->ptn_bridge->encoder = encoder;
> - ret = drm_bridge_attach(encoder->dev, dp->ptn_bridge);
> + ret = drm_bridge_attach(&dp->encoder, dp->ptn_bridge, bridge);
> if (ret) {
> DRM_ERROR("Failed to attach bridge to drm\n");
> bridge->next = NULL;
> diff --git a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> index e07cb1fe4860..812e2ec0761d 100644
> --- a/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> +++ b/drivers/gpu/drm/exynos/exynos_drm_dsi.c
> @@ -1718,10 +1718,8 @@ static int exynos_dsi_bind(struct device *dev, struct
> device *master,
> }
>
> bridge = of_drm_find_bridge(dsi->bridge_node);
> - if (bridge) {
> - encoder->bridge = bridge;
> - drm_bridge_attach(drm_dev, bridge);
> - }
> + if (bridge)
> + drm_bridge_attach(encoder, bridge, NULL);
>
> return mipi_dsi_host_register(&dsi->dsi_host);
> }
> diff --git a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
> b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
> index e1dd75b18118..3ad76423c60d 100644
> --- a/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
> +++ b/drivers/gpu/drm/fsl-dcu/fsl_dcu_drm_rgb.c
> @@ -167,10 +167,7 @@ static int fsl_dcu_attach_endpoint(struct
> fsl_dcu_drm_device *fsl_dev,
> if (!bridge)
> return -ENODEV;
>
> - fsl_dev->encoder.bridge = bridge;
> - bridge->encoder = &fsl_dev->encoder;
> -
> - return drm_bridge_attach(fsl_dev->drm, bridge);
> + return drm_bridge_attach(&fsl_dev->encoder, bridge, NULL);
> }
>
> int fsl_dcu_create_outputs(struct fsl_dcu_drm_device *fsl_dev)
> diff --git a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
> b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
> index 998452ad0fcb..1737e98bc10a 100644
> --- a/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
> +++ b/drivers/gpu/drm/hisilicon/kirin/dw_drm_dsi.c
> @@ -709,10 +709,7 @@ static int dsi_bridge_init(struct drm_device *dev,
> struct dw_dsi *dsi)
> int ret;
>
> /* associate the bridge to dsi encoder */
> - encoder->bridge = bridge;
> - bridge->encoder = encoder;
> -
> - ret = drm_bridge_attach(dev, bridge);
> + ret = drm_bridge_attach(encoder, bridge, NULL);
> if (ret) {
> DRM_ERROR("failed to attach external bridge\n");
> return ret;
> diff --git a/drivers/gpu/drm/imx/imx-ldb.c b/drivers/gpu/drm/imx/imx-ldb.c
> index b300998dce7d..2fcb579f5489 100644
> --- a/drivers/gpu/drm/imx/imx-ldb.c
> +++ b/drivers/gpu/drm/imx/imx-ldb.c
> @@ -461,10 +461,8 @@ static int imx_ldb_register(struct drm_device *drm,
> DRM_MODE_ENCODER_LVDS, NULL);
>
> if (imx_ldb_ch->bridge) {
> - imx_ldb_ch->bridge->encoder = encoder;
> -
> - imx_ldb_ch->encoder.bridge = imx_ldb_ch->bridge;
> - ret = drm_bridge_attach(drm, imx_ldb_ch->bridge);
> + ret = drm_bridge_attach(&imx_ldb_ch->encoder,
> + imx_ldb_ch->bridge, NULL);
> if (ret) {
> DRM_ERROR("Failed to initialize bridge with drm\n");
> return ret;
> diff --git a/drivers/gpu/drm/imx/parallel-display.c
> b/drivers/gpu/drm/imx/parallel-display.c
> index d796ada2a47a..2d80c769f56b 100644
> --- a/drivers/gpu/drm/imx/parallel-display.c
> +++ b/drivers/gpu/drm/imx/parallel-display.c
> @@ -198,9 +198,7 @@ static int imx_pd_register(struct drm_device *drm,
> drm_panel_attach(imxpd->panel, &imxpd->connector);
>
> if (imxpd->bridge) {
> - imxpd->bridge->encoder = encoder;
> - encoder->bridge = imxpd->bridge;
> - ret = drm_bridge_attach(drm, imxpd->bridge);
> + ret = drm_bridge_attach(encoder, imxpd->bridge, NULL);
> if (ret < 0) {
> dev_err(imxpd->dev, "failed to attach bridge: %d\n",
> ret);
> diff --git a/drivers/gpu/drm/mediatek/mtk_dpi.c
> b/drivers/gpu/drm/mediatek/mtk_dpi.c
> index 0186e500d2a5..3cced1c522fd 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dpi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dpi.c
> @@ -63,6 +63,7 @@ enum mtk_dpi_out_color_format {
> struct mtk_dpi {
> struct mtk_ddp_comp ddp_comp;
> struct drm_encoder encoder;
> + struct drm_bridge *bridge;
> void __iomem *regs;
> struct device *dev;
> struct clk *engine_clk;
> @@ -615,8 +616,7 @@ static int mtk_dpi_bind(struct device *dev, struct device
> *master, void *data)
> /* Currently DPI0 is fixed to be driven by OVL1 */
> dpi->encoder.possible_crtcs = BIT(1);
>
> - dpi->encoder.bridge->encoder = &dpi->encoder;
> - ret = drm_bridge_attach(dpi->encoder.dev, dpi->encoder.bridge);
> + ret = drm_bridge_attach(&dpi->encoder, dpi->bridge, NULL);
> if (ret) {
> dev_err(dev, "Failed to attach bridge: %d\n", ret);
> goto err_cleanup;
> @@ -713,9 +713,9 @@ static int mtk_dpi_probe(struct platform_device *pdev)
>
> dev_info(dev, "Found bridge node: %s\n", bridge_node->full_name);
>
> - dpi->encoder.bridge = of_drm_find_bridge(bridge_node);
> + dpi->bridge = of_drm_find_bridge(bridge_node);
> of_node_put(bridge_node);
> - if (!dpi->encoder.bridge)
> + if (!dpi->bridge)
> return -EPROBE_DEFER;
>
> comp_id = mtk_ddp_comp_get_id(dev->of_node, MTK_DPI);
> diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c
> b/drivers/gpu/drm/mediatek/mtk_dsi.c
> index 28b2044ed9f2..2ac0f1abba86 100644
> --- a/drivers/gpu/drm/mediatek/mtk_dsi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
> @@ -597,26 +597,6 @@ static const struct drm_connector_helper_funcs
> .get_modes = mtk_dsi_connector_get_modes,
> };
>
> -static int mtk_drm_attach_bridge(struct drm_bridge *bridge,
> - struct drm_encoder *encoder)
> -{
> - int ret;
> -
> - if (!bridge)
> - return -ENOENT;
> -
> - encoder->bridge = bridge;
> - bridge->encoder = encoder;
> - ret = drm_bridge_attach(encoder->dev, bridge);
> - if (ret) {
> - DRM_ERROR("Failed to attach bridge to drm\n");
> - encoder->bridge = NULL;
> - bridge->encoder = NULL;
> - }
> -
> - return ret;
> -}
> -
> static int mtk_dsi_create_connector(struct drm_device *drm, struct mtk_dsi
> *dsi)
> {
> int ret;
> @@ -667,8 +647,10 @@ 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 = mtk_drm_attach_bridge(dsi->bridge, &dsi->encoder);
> + 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)
> diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> index 71227deef21b..5ca1b0fbf937 100644
> --- a/drivers/gpu/drm/mediatek/mtk_hdmi.c
> +++ b/drivers/gpu/drm/mediatek/mtk_hdmi.c
> @@ -149,6 +149,7 @@ struct hdmi_audio_param {
>
> struct mtk_hdmi {
> struct drm_bridge bridge;
> + struct drm_bridge *next_bridge;
> struct drm_connector conn;
> struct device *dev;
> struct phy *phy;
> @@ -1320,9 +1321,9 @@ static int mtk_hdmi_bridge_attach(struct drm_bridge
> *bridge)
> return ret;
> }
>
> - if (bridge->next) {
> - bridge->next->encoder = bridge->encoder;
> - ret = drm_bridge_attach(bridge->encoder->dev, bridge->next);
> + if (hdmi->next_bridge) {
> + ret = drm_bridge_attach(bridge->encoder, hdmi->next_bridge,
> + bridge);
> if (ret) {
> dev_err(hdmi->dev,
> "Failed to attach external bridge: %d\n", ret);
> @@ -1505,8 +1506,8 @@ static int mtk_hdmi_dt_parse_pdata(struct mtk_hdmi
> *hdmi,
> of_node_put(ep);
>
> if (!of_device_is_compatible(remote, "hdmi-connector")) {
> - hdmi->bridge.next = of_drm_find_bridge(remote);
> - if (!hdmi->bridge.next) {
> + hdmi->next_bridge = of_drm_find_bridge(remote);
> + if (!hdmi->next_bridge) {
> dev_err(dev, "Waiting for external bridge\n");
> of_node_put(remote);
> return -EPROBE_DEFER;
> diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c
> b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> index c8d1f19c9a6d..2bd8dad76105 100644
> --- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
> +++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
> @@ -579,6 +579,7 @@ struct drm_bridge *msm_dsi_manager_bridge_init(u8 id)
> struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
> struct drm_bridge *bridge = NULL;
> struct dsi_bridge *dsi_bridge;
> + struct drm_encoder *encoder;
> int ret;
>
> dsi_bridge = devm_kzalloc(msm_dsi->dev->dev,
> @@ -590,10 +591,18 @@ struct drm_bridge *msm_dsi_manager_bridge_init(u8 id)
>
> dsi_bridge->id = id;
>
> + /*
> + * HACK: we may not know the external DSI bridge device's mode
> + * flags here. We'll get to know them only when the device
> + * attaches to the dsi host. For now, assume the bridge supports
> + * DSI video mode
> + */
> + encoder = msm_dsi->encoders[MSM_DSI_VIDEO_ENCODER_ID];
> +
> bridge = &dsi_bridge->base;
> bridge->funcs = &dsi_mgr_bridge_funcs;
>
> - ret = drm_bridge_attach(msm_dsi->dev, bridge);
> + ret = drm_bridge_attach(encoder, bridge, NULL);
> if (ret)
> goto fail;
>
> @@ -628,11 +637,7 @@ struct drm_connector *msm_dsi_manager_ext_bridge_init(u8
> id)
> encoder = msm_dsi->encoders[MSM_DSI_VIDEO_ENCODER_ID];
>
> /* link the internal dsi bridge to the external bridge */
> - int_bridge->next = ext_bridge;
> - /* set the external bridge's encoder as dsi's encoder */
> - ext_bridge->encoder = encoder;
> -
> - drm_bridge_attach(dev, ext_bridge);
> + drm_bridge_attach(encoder, ext_bridge, int_bridge);
>
> /*
> * we need the drm_connector created by the external bridge
> diff --git a/drivers/gpu/drm/msm/edp/edp_bridge.c
> b/drivers/gpu/drm/msm/edp/edp_bridge.c
> index 2bc73f82f3f5..931a5c97cccf 100644
> --- a/drivers/gpu/drm/msm/edp/edp_bridge.c
> +++ b/drivers/gpu/drm/msm/edp/edp_bridge.c
> @@ -106,7 +106,7 @@ struct drm_bridge *msm_edp_bridge_init(struct msm_edp
> *edp)
> bridge = &edp_bridge->base;
> bridge->funcs = &edp_bridge_funcs;
>
> - ret = drm_bridge_attach(edp->dev, bridge);
> + ret = drm_bridge_attach(edp->encoder, bridge, NULL);
> if (ret)
> goto fail;
>
> diff --git a/drivers/gpu/drm/msm/hdmi/hdmi_bridge.c
> b/drivers/gpu/drm/msm/hdmi/hdmi_bridge.c
> index bacbd5d8df0e..4e6d1bf27474 100644
> --- a/drivers/gpu/drm/msm/hdmi/hdmi_bridge.c
> +++ b/drivers/gpu/drm/msm/hdmi/hdmi_bridge.c
> @@ -227,7 +227,7 @@ struct drm_bridge *msm_hdmi_bridge_init(struct hdmi *hdmi)
> bridge = &hdmi_bridge->base;
> bridge->funcs = &msm_hdmi_bridge_funcs;
>
> - ret = drm_bridge_attach(hdmi->dev, bridge);
> + ret = drm_bridge_attach(hdmi->encoder, bridge, NULL);
> if (ret)
> goto fail;
>
> diff --git a/drivers/gpu/drm/rcar-du/rcar_du_hdmienc.c
> b/drivers/gpu/drm/rcar-du/rcar_du_hdmienc.c
> index a1a2c5e7822c..933a2547798e 100644
> --- a/drivers/gpu/drm/rcar-du/rcar_du_hdmienc.c
> +++ b/drivers/gpu/drm/rcar-du/rcar_du_hdmienc.c
> @@ -124,10 +124,7 @@ int rcar_du_hdmienc_init(struct rcar_du_device *rcdu,
> hdmienc->renc = renc;
>
> /* Link the bridge to the encoder. */
> - bridge->encoder = encoder;
> - encoder->bridge = bridge;
> -
> - ret = drm_bridge_attach(rcdu->ddev, bridge);
> + ret = drm_bridge_attach(encoder, bridge, NULL);
> if (ret) {
> drm_encoder_cleanup(encoder);
> return ret;
> diff --git a/drivers/gpu/drm/sti/sti_dvo.c b/drivers/gpu/drm/sti/sti_dvo.c
> index e8c1ed08a9f7..411dc6ec976e 100644
> --- a/drivers/gpu/drm/sti/sti_dvo.c
> +++ b/drivers/gpu/drm/sti/sti_dvo.c
> @@ -478,14 +478,13 @@ static int sti_dvo_bind(struct device *dev, struct
> device *master, void *data)
> return err;
> }
>
> - err = drm_bridge_attach(drm_dev, bridge);
> + err = drm_bridge_attach(encoder, bridge, NULL);
> if (err) {
> DRM_ERROR("Failed to attach bridge\n");
> return err;
> }
>
> dvo->bridge = bridge;
> - encoder->bridge = bridge;
> connector->encoder = encoder;
> dvo->encoder = encoder;
>
> diff --git a/drivers/gpu/drm/sti/sti_hda.c b/drivers/gpu/drm/sti/sti_hda.c
> index e7c243f70870..5b1855e44f87 100644
> --- a/drivers/gpu/drm/sti/sti_hda.c
> +++ b/drivers/gpu/drm/sti/sti_hda.c
> @@ -714,9 +714,8 @@ static int sti_hda_bind(struct device *dev, struct device
> *master, void *data)
>
> bridge->driver_private = hda;
> bridge->funcs = &sti_hda_bridge_funcs;
> - drm_bridge_attach(drm_dev, bridge);
> + drm_bridge_attach(encoder, bridge, NULL);
>
> - encoder->bridge = bridge;
> connector->encoder = encoder;
>
> drm_connector = (struct drm_connector *)connector;
> diff --git a/drivers/gpu/drm/sti/sti_hdmi.c b/drivers/gpu/drm/sti/sti_hdmi.c
> index 376b0763c874..f0af1ae82ee9 100644
> --- a/drivers/gpu/drm/sti/sti_hdmi.c
> +++ b/drivers/gpu/drm/sti/sti_hdmi.c
> @@ -1308,9 +1308,8 @@ static int sti_hdmi_bind(struct device *dev, struct
> device *master, void *data)
>
> bridge->driver_private = hdmi;
> bridge->funcs = &sti_hdmi_bridge_funcs;
> - drm_bridge_attach(drm_dev, bridge);
> + drm_bridge_attach(encoder, bridge, NULL);
>
> - encoder->bridge = bridge;
> connector->encoder = encoder;
>
> drm_connector = (struct drm_connector *)connector;
> diff --git a/drivers/gpu/drm/sun4i/sun4i_rgb.c
> b/drivers/gpu/drm/sun4i/sun4i_rgb.c
> index c3ff10f559cc..ce071c17134b 100644
> --- a/drivers/gpu/drm/sun4i/sun4i_rgb.c
> +++ b/drivers/gpu/drm/sun4i/sun4i_rgb.c
> @@ -219,6 +219,7 @@ int sun4i_rgb_init(struct drm_device *drm)
> struct sun4i_drv *drv = drm->dev_private;
> struct sun4i_tcon *tcon = drv->tcon;
> struct drm_encoder *encoder;
> + struct drm_bridge *bridge;
> struct sun4i_rgb *rgb;
> int ret;
>
> @@ -229,8 +230,8 @@ int sun4i_rgb_init(struct drm_device *drm)
> encoder = &rgb->encoder;
>
> tcon->panel = sun4i_tcon_find_panel(tcon->dev->of_node);
> - encoder->bridge = sun4i_tcon_find_bridge(tcon->dev->of_node);
> - if (IS_ERR(tcon->panel) && IS_ERR(encoder->bridge)) {
> + bridge = sun4i_tcon_find_bridge(tcon->dev->of_node);
> + if (IS_ERR(tcon->panel) && IS_ERR(bridge)) {
> dev_info(drm->dev, "No panel or bridge found... RGB output
> disabled\n");
> return 0;
> }
> @@ -271,16 +272,12 @@ int sun4i_rgb_init(struct drm_device *drm)
> }
> }
>
> - if (!IS_ERR(encoder->bridge)) {
> - encoder->bridge->encoder = &rgb->encoder;
> -
> - ret = drm_bridge_attach(drm, encoder->bridge);
> + if (!IS_ERR(bridge)) {
> + ret = drm_bridge_attach(encoder, bridge, NULL);
> if (ret) {
> dev_err(drm->dev, "Couldn't attach our bridge\n");
> goto err_cleanup_connector;
> }
> - } else {
> - encoder->bridge = NULL;
> }
>
> return 0;
> diff --git a/include/drm/drm_bridge.h b/include/drm/drm_bridge.h
> index 530a1d6e8cde..94e5ee96b3b5 100644
> --- a/include/drm/drm_bridge.h
> +++ b/include/drm/drm_bridge.h
> @@ -201,7 +201,8 @@ struct drm_bridge {
> int drm_bridge_add(struct drm_bridge *bridge);
> void drm_bridge_remove(struct drm_bridge *bridge);
> struct drm_bridge *of_drm_find_bridge(struct device_node *np);
> -int drm_bridge_attach(struct drm_device *dev, struct drm_bridge *bridge);
> +int drm_bridge_attach(struct drm_encoder *encoder, struct drm_bridge *bridge,
> + struct drm_bridge *previous);
> void drm_bridge_detach(struct drm_bridge *bridge);
>
> bool drm_bridge_mode_fixup(struct drm_bridge *bridge,
