drm: bridge: Link encoder and bridge in core code

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+renesas@ideasonboard.com>
Acked-by: Stefan Agner <stefan@agner.ch> # For DCU
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com> # For atmel-hlcdc
Acked-by: Vincent Abriou <vincent.abriou@st.com> # For STI
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com> # For sun4i
Acked-by: Xinliang Liu <z.liuxinliang@hisilicon.com> # For hisilicon
Acked-by: Jyri Sarha <jsarha@ti.com> # For tilcdc
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Archit Taneja <architt@codeaurora.org>
Link: http://patchwork.freedesktop.org/patch/msgid/1481709550-29226-4-git-send-email-laurent.pinchart+renesas@ideasonboard.com
diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index c8d1f19..2bd8dad 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -579,6 +579,7 @@
 	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 @@
 
 	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 @@
 	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 2bc73f82..931a5c9 100644
--- a/drivers/gpu/drm/msm/edp/edp_bridge.c
+++ b/drivers/gpu/drm/msm/edp/edp_bridge.c
@@ -106,7 +106,7 @@
 	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 bacbd5d..4e6d1bf 100644
--- a/drivers/gpu/drm/msm/hdmi/hdmi_bridge.c
+++ b/drivers/gpu/drm/msm/hdmi/hdmi_bridge.c
@@ -227,7 +227,7 @@
 	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;