On 3/9/2024 7:09 AM, Dmitry Baryshkov wrote:
Currently the MSM DSI driver looks for the next bridge during
msm_dsi_modeset_init(). If the bridge is not registered at that point,
this might result in -EPROBE_DEFER, which can be problematic that late
during the device probe process. Move next bridge acquisition to the
dsi_bind state so that probe deferral is returned as early as possible.
But msm_dsi_modeset)init() is also called during msm_drm_bind() only.
What issue are you suggesting will be fixed by moving this from
msm_drm_bind() to dsi_bind()?
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/gpu/drm/msm/dsi/dsi.c | 16 ++++++++++++++++
drivers/gpu/drm/msm/dsi/dsi.h | 2 ++
drivers/gpu/drm/msm/dsi/dsi_manager.c | 8 +-------
3 files changed, 19 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/msm/dsi/dsi.c b/drivers/gpu/drm/msm/dsi/dsi.c
index 37c4c07005fe..38f10f7a10d3 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.c
+++ b/drivers/gpu/drm/msm/dsi/dsi.c
@@ -120,6 +120,22 @@ static int dsi_bind(struct device *dev, struct device *master, void *data)
struct msm_drm_private *priv = dev_get_drvdata(master);
struct msm_dsi *msm_dsi = dev_get_drvdata(dev);
+ /*
+ * Next bridge doesn't exist for the secondary DSI host in a bonded
+ * pair.
+ */
+ if (!msm_dsi_is_bonded_dsi(msm_dsi) ||
+ msm_dsi_is_master_dsi(msm_dsi)) {
+ struct drm_bridge *ext_bridge;
+
+ ext_bridge = devm_drm_of_get_bridge(&msm_dsi->pdev->dev,
+ msm_dsi->pdev->dev.of_node, 1, 0);
+ if (IS_ERR(ext_bridge))
+ return PTR_ERR(ext_bridge);
+
+ msm_dsi->next_bridge = ext_bridge;
+ }
+
priv->dsi[msm_dsi->id] = msm_dsi;
return 0;
diff --git a/drivers/gpu/drm/msm/dsi/dsi.h b/drivers/gpu/drm/msm/dsi/dsi.h
index 2ad9a842c678..0adef65be1de 100644
--- a/drivers/gpu/drm/msm/dsi/dsi.h
+++ b/drivers/gpu/drm/msm/dsi/dsi.h
@@ -38,6 +38,8 @@ struct msm_dsi {
struct mipi_dsi_host *host;
struct msm_dsi_phy *phy;
+ struct drm_bridge *next_bridge;
+
struct device *phy_dev;
bool phy_enabled;
diff --git a/drivers/gpu/drm/msm/dsi/dsi_manager.c b/drivers/gpu/drm/msm/dsi/dsi_manager.c
index a7c7f85b73e4..b7c52b14c790 100644
--- a/drivers/gpu/drm/msm/dsi/dsi_manager.c
+++ b/drivers/gpu/drm/msm/dsi/dsi_manager.c
@@ -464,18 +464,12 @@ int msm_dsi_manager_ext_bridge_init(u8 id, struct drm_bridge *int_bridge)
struct msm_dsi *msm_dsi = dsi_mgr_get_dsi(id);
struct drm_device *dev = msm_dsi->dev;
struct drm_encoder *encoder;
- struct drm_bridge *ext_bridge;
struct drm_connector *connector;
int ret;
- ext_bridge = devm_drm_of_get_bridge(&msm_dsi->pdev->dev,
- msm_dsi->pdev->dev.of_node, 1, 0);
- if (IS_ERR(ext_bridge))
- return PTR_ERR(ext_bridge);
-
encoder = int_bridge->encoder;
- ret = drm_bridge_attach(encoder, ext_bridge, int_bridge,
+ ret = drm_bridge_attach(encoder, msm_dsi->next_bridge, int_bridge,
DRM_BRIDGE_ATTACH_NO_CONNECTOR);
if (ret)
return ret;