Hi Dmitry,
On 9/25/2025 11:37 AM, Dmitry Baryshkov wrote:
On Wed, Sep 24, 2025 at 05:14:57PM +0800, Damon Ding wrote:
Hi Dmitry,
On 9/12/2025 7:03 PM, Dmitry Baryshkov wrote:
On Fri, Sep 12, 2025 at 04:58:39PM +0800, Damon Ding wrote:
Apply drm_bridge_connector helper for Analogix DP driver.
The following changes have been made:
- Apply drm_bridge_connector helper to get rid of &drm_connector_funcs
and &drm_connector_helper_funcs.
- Remove unnecessary parameter struct drm_connector* for callback
&analogix_dp_plat_data.attach.
- Remove &analogix_dp_device.connector.
- Convert analogix_dp_atomic_check()/analogix_dp_detect() to
&drm_bridge_funcs.atomic_check()/&drm_bridge_funcs.detect().
- Split analogix_dp_get_modes() into &drm_bridge_funcs.get_modes() and
&drm_bridge_funcs.edid_read().
Signed-off-by: Damon Ding <[email protected]>
------
Changes in v2:
- For &drm_bridge.ops, remove DRM_BRIDGE_OP_HPD and add
DRM_BRIDGE_OP_EDID.
- Add analogix_dp_bridge_edid_read().
- Move &analogix_dp_plat_data.skip_connector deletion to the previous
patches.
Changes in v3:
- Rebase with the new devm_drm_bridge_alloc() related commit
48f05c3b4b70 ("drm/bridge: analogix_dp: Use devm_drm_bridge_alloc()
API").
- Expand the commit message.
- Call drm_bridge_get_modes() in analogix_dp_bridge_get_modes() if the
bridge is available.
- Remove unnecessary parameter struct drm_connector* for callback
&analogix_dp_plat_data.attach.
- In order to decouple the connector driver and the bridge driver, move
the bridge connector initilization to the Rockchip and Exynos sides.
Changes in v4:
- Expand analogix_dp_bridge_detect() parameters to &drm_bridge and
&drm_connector.
- Rename the &analogix_dp_plat_data.bridge to
&analogix_dp_plat_data.next_bridge.
Changes in v5:
- Set the flag fo drm_bridge_attach() to DRM_BRIDGE_ATTACH_NO_CONNECTOR
for next bridge attachment of Exynos side.
- Distinguish the &drm_bridge->ops of Analogix bridge based on whether
the downstream device is a panel, a bridge or neither.
- Remove the calls to &analogix_dp_plat_data.get_modes().
---
.../drm/bridge/analogix/analogix_dp_core.c | 151 ++++++++----------
.../drm/bridge/analogix/analogix_dp_core.h | 1 -
drivers/gpu/drm/exynos/exynos_dp.c | 25 +--
.../gpu/drm/rockchip/analogix_dp-rockchip.c | 11 +-
include/drm/bridge/analogix_dp.h | 3 +-
5 files changed, 95 insertions(+), 96 deletions(-)
@@ -1532,6 +1487,7 @@ EXPORT_SYMBOL_GPL(analogix_dp_resume);
int analogix_dp_bind(struct analogix_dp_device *dp, struct drm_device
*drm_dev)
{
+ struct drm_bridge *bridge = &dp->bridge;
int ret;
dp->drm_dev = drm_dev;
@@ -1545,7 +1501,23 @@ int analogix_dp_bind(struct analogix_dp_device *dp,
struct drm_device *drm_dev)
return ret;
}
- ret = drm_bridge_attach(dp->encoder, &dp->bridge, NULL, 0);
+ if (dp->plat_data->panel)
+ /* If the next is a panel, the EDID parsing is checked by the
panel driver */
+ bridge->ops = DRM_BRIDGE_OP_MODES | DRM_BRIDGE_OP_DETECT;
+ else if (dp->plat_data->next_bridge)
+ /* If the next is a bridge, the supported operations depend on
the next bridge */
+ bridge->ops = 0;
And what if the next bridge is dp_connector without a separate HPD pin?
This case was indeed not taken into account.
If the next is a bridge, it should be better to set DRM_BRIDGE_OP_DETECT and
return connector_status_connected in analogix_dp_bridge_detect(). This
ensures the connection status remains connected for both the dp-connector
and the bridges without DRM_BRIDGE_OP_DETECT.
Maybe OP_EDID | OP_DETECT? I think, we need to fix drm_bridge_connector
to stop preferring OP_EDID bridges over OP_MODES if the latter one is
enountered later in the chain. In other words inside
drm_bridge_connector_init() clear bridge_edid if OP_MODES is encountered
and vice versa. This way you can always declare OP_EDID here (after
converting to panel bridge) and then letting panel's OP_MODES take over
mode declaration. Would you please include such a patch in the next
iteration?
I see. Following your suggestions, the logic will be:
1.If the later bridge declares OP_MODES and
&drm_bridge_connector.bridge_edid already exists, the
&drm_bridge_connector.bridge_edid should be set to NULL.
2.If the later bridge declares OP_EDID and
&drm_bridge_connector.bridge_modes already exists, the
&drm_bridge_connector.bridge_modes should be set to NULL.
3.If the later bridge declares both OP_EDID and OP_MODES, set
&drm_bridge_connector.bridge_modes and &drm_bridge_connector.bridge_edid
to it(preserving the existing behavior).
I will add a new commit with necessary code comments to implement this
in v6.
+ else
+ /* In DP mode, the EDID parsing and HPD detection should be
supported */
+ bridge->ops = DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_DETECT;
+
+ bridge->of_node = dp->dev->of_node;
+ bridge->type = DRM_MODE_CONNECTOR_eDP;
+ ret = devm_drm_bridge_add(dp->dev, &dp->bridge);
+ if (ret)
+ goto err_unregister_aux;
+
+ ret = drm_bridge_attach(dp->encoder, bridge, NULL, 0);
if (ret) {
DRM_ERROR("failed to create bridge (%d)\n", ret);
goto err_unregister_aux;
Best regards,
Damon
