On 11/3/2025 12:00 PM, Dmitry Baryshkov wrote:
On Wed, Oct 29, 2025 at 03:14:28PM +0800, Chaoyi Chen wrote:
From: Chaoyi Chen <[email protected]>
Several USB-C controller drivers have already implemented the DP HPD
bridge function provided by aux-hpd-bridge.c, but there are still
some USB-C controller driver that have not yet implemented it.
This patch implements a generic DP HPD bridge based on aux-hpd-bridge.c,
so that other USB-C controller drivers don't need to implement it again.
This doesn't describe the problem that you are trying to solve.
Signed-off-by: Chaoyi Chen <[email protected]>
---
Changes in v8:
- Merge generic DP HPD bridge into one module.
drivers/gpu/drm/bridge/Kconfig | 5 +-
drivers/gpu/drm/bridge/Makefile | 8 +++-
drivers/gpu/drm/bridge/aux-hpd-bridge.c | 23 ++++++++-
drivers/gpu/drm/bridge/aux-hpd-bridge.h | 13 +++++
.../gpu/drm/bridge/aux-hpd-typec-dp-bridge.c | 47 +++++++++++++++++++
5 files changed, 93 insertions(+), 3 deletions(-)
create mode 100644 drivers/gpu/drm/bridge/aux-hpd-bridge.h
create mode 100644 drivers/gpu/drm/bridge/aux-hpd-typec-dp-bridge.c
diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
index a250afd8d662..17257b223a28 100644
--- a/drivers/gpu/drm/bridge/Kconfig
+++ b/drivers/gpu/drm/bridge/Kconfig
@@ -23,13 +23,16 @@ config DRM_AUX_BRIDGE
build bridges chain.
config DRM_AUX_HPD_BRIDGE
- tristate
+ tristate "AUX HPD bridge support"
Why? No, this is supposed to be selected by other drivers. Users don't
know an wouldn't know what is this.
Sorry, I might have misunderstood you point. In v7, I added a new
DRM_AUX_TYPEC_DP_HPD_BRIDGE module to select DRM_AUX_HPD_BRIDGE. This seems to fit the
"selected by other drivers" scenario, but I think you might not want to expose
any information to the users.
And the other one is what Heikki said:
+if DRM_AUX_HPD_BRIDGE + +config DRM_AUX_HPD_TYPEC_BRIDGE + tristate + depends on TYPEC || !TYPEC
+ default TYPEC + +endif /* DRM_AUX_HPD_BRIDGE */ + menu "Display Interface Bridges"
depends on DRM && DRM_BRIDGE
If I understand correctly, in this scenario we need to select
DRM_AUX_HPD_BRIDGE in the DP driver. When Type-C is available,
DRM_AUX_HPD_TYPEC_BRIDGE will be selected automatically.
Is the method mentioned by Heikki what you want? Thank you.
--
Best,
Chaoyi
