Hi Marek,
On 2025/8/15 5:16, Marek Szyprowski wrote:
On 14.08.2025 16:33, Marek Szyprowski wrote:
On 14.08.2025 12:47, Damon Ding wrote:
PATCH 1 is a small format optimization for struct analogid_dp_device.
PATCH 2 is to perform mode setting in &drm_bridge_funcs.atomic_enable.
PATCH 3-6 are preparations for apply drm_bridge_connector helper.
PATCH 7 is to apply the drm_bridge_connector helper.
PATCH 8-10 are to move the panel/bridge parsing to the Analogix side.
PATCH 11-12 are preparations for apply panel_bridge helper.
PATCH 13 is to apply the panel_bridge helper.
This series lacks 'select DRM_BRIDGE_CONNECTOR' in ExynosDP's Kconfig,
so it causes build break:
drivers/gpu/drm/exynos/exynos_dp.c:177: undefined reference to
`drm_bridge_connector_init'
make[2]: *** [scripts/Makefile.vmlinux:91: vmlinux] Error 1
After adding this dependency, the Exynos DP driver stops working. On
Samsung Snow Chromebook I observed following issue:
[ 4.534220] exynos-dp 145b0000.dp-controller: failed to attach
following panel or bridge (-16)
[ 4.543428] exynos-drm exynos-drm: failed to bind
145b0000.dp-controller (ops exynos_dp_ops): -16
[ 4.551775] exynos-drm exynos-drm: adev bind failed: -16
[ 4.556559] exynos-dp 145b0000.dp-controller: probe with driver
exynos-dp failed with error -16
I will investigate details later in the evening.
The failure is caused by trying to add plat_data->next_bridge twice
(from exynos_dp's .attach callback, and from analogix' ->bind callback).
Best regards
I see. The bridge attachment for the next bridge was not well thought
out. It may be better to move panel_bridge addition a little forward and
remove next_bridge attachment on the Analogix side. Then, the Rockchip
side and Exynos side can do their own next_bridge attachment in
&analogix_dp_plat_data.attach() as they want.
Could you please help test the following modifications(they have been
tested on my RK3588S EVB1 Board) on the Samsung Snow Chromebook? ;-)
diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
index 0529bfb02884..8a9ce1f31678 100644
--- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
+++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.c
@@ -1573,6 +1573,15 @@ int analogix_dp_bind(struct analogix_dp_device
*dp, struct drm_device *drm_dev)
return ret;
}
+ if (dp->plat_data->panel) {
+ dp->plat_data->next_bridge =
devm_drm_panel_bridge_add(dp->dev,
+
dp->plat_data->panel);
+ if (IS_ERR(dp->plat_data->next_bridge)) {
+ ret = PTR_ERR(bridge);
+ goto err_unregister_aux;
+ }
+ }
+
bridge->ops = DRM_BRIDGE_OP_DETECT |
DRM_BRIDGE_OP_EDID |
DRM_BRIDGE_OP_MODES;
@@ -1588,22 +1597,6 @@ int analogix_dp_bind(struct analogix_dp_device
*dp, struct drm_device *drm_dev)
goto err_unregister_aux;
}
- if (dp->plat_data->panel) {
- dp->plat_data->next_bridge =
devm_drm_panel_bridge_add(dp->dev,
-
dp->plat_data->panel);
- if (IS_ERR(dp->plat_data->next_bridge)) {
- ret = PTR_ERR(bridge);
- goto err_unregister_aux;
- }
- }
-
- ret = drm_bridge_attach(dp->encoder, dp->plat_data->next_bridge,
bridge,
- DRM_BRIDGE_ATTACH_NO_CONNECTOR);
- if (ret) {
- dev_err(dp->dev, "failed to attach following panel or
bridge (%d)\n", ret);
- goto err_unregister_aux;
- }
-
return 0;
err_unregister_aux:
diff --git a/drivers/gpu/drm/exynos/exynos_dp.c
b/drivers/gpu/drm/exynos/exynos_dp.c
index 80ba700d2964..d0422f940249 100644
--- a/drivers/gpu/drm/exynos/exynos_dp.c
+++ b/drivers/gpu/drm/exynos/exynos_dp.c
@@ -104,7 +104,7 @@ static int exynos_dp_bridge_attach(struct
analogix_dp_plat_data *plat_data,
/* Pre-empt DP connector creation if there's a bridge */
if (plat_data->next_bridge) {
ret = drm_bridge_attach(&dp->encoder,
plat_data->next_bridge, bridge,
- 0);
+ DRM_BRIDGE_ATTACH_NO_CONNECTOR);
if (ret)
return ret;
}
diff --git a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
index 0862b09a8be2..dfd32a79b94f 100644
--- a/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
+++ b/drivers/gpu/drm/rockchip/analogix_dp-rockchip.c
@@ -164,6 +164,24 @@ static int rockchip_dp_powerdown(struct
analogix_dp_plat_data *plat_data)
return 0;
}
+static int rockchip_dp_attach(struct analogix_dp_plat_data *plat_data,
+ struct drm_bridge *bridge)
+{
+ struct rockchip_dp_device *dp = pdata_encoder_to_dp(plat_data);
+ int ret;
+
+ if (plat_data->next_bridge) {
+ ret = drm_bridge_attach(&dp->encoder.encoder,
plat_data->next_bridge, bridge,
+ DRM_BRIDGE_ATTACH_NO_CONNECTOR);
+ if (ret) {
+ dev_err(dp->dev, "failed to attach following
panel or bridge (%d)\n", ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
static int rockchip_dp_get_modes(struct analogix_dp_plat_data *plat_data,
struct drm_connector *connector)
{
@@ -478,6 +496,7 @@ static int rockchip_dp_probe(struct platform_device
*pdev)
dp->plat_data.dev_type = dp->data->chip_type;
dp->plat_data.power_on = rockchip_dp_poweron;
dp->plat_data.power_off = rockchip_dp_powerdown;
+ dp->plat_data.attach = rockchip_dp_attach;
dp->plat_data.get_modes = rockchip_dp_get_modes;
dp->plat_data.ops = &rockchip_dp_component_ops;
Best regards,
Damon
