usb: typec: altmodes: select DRM_AUX_HPD_BRIDGE for TYPEC_DP_ALTMODE

PATCH In review Chaoyi Chen 3 participants 6 messages Jul 9 – Jul 16

Subsystems (3)

USB USB Type-C class USB Type-C bus for alternate modes

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Chaoyi Chen

author

2026-07-09 06:22 UTC #0 lore raw

PATCH v3 1/1 usb: typec: altmodes: select DRM_AUX_HPD_BRIDGE for TYPEC_DP_ALTMODE

From: Chaoyi Chen <[email protected]>

When TYPEC_DP_ALTMODE is enabled, DRM_AUX_HPD_BRIDGE is most likely also needed for embedded platforms. Select it when available.

Suggested-by Xu Yang <[email protected]>

Signed-off-by Chaoyi Chen <[email protected]>

---
Changes in v3:
- Link to v2: https://lore.kernel.org/all/[email protected]/
- Use the same "select" as v1 to make things simple.

Changes in v2:
- Link to v1: https://lore.kernel.org/all/[email protected]/
- Change "select" to "imply".
---

 drivers/usb/typec/altmodes/Kconfig | 1 +
 1 file changed, 1 insertion(+)

drivers/usb/typec/altmodes/Kconfig +1 -0

index 7867fa7c405d..b054c0b6a8d4 100644
@@ -5,6 +5,7 @@ menu "USB Type-C Alternate Mode drivers"
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
 	depends on DRM
+	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE && OF
 	help
 	  DisplayPort USB Type-C Alternate Mode allows DisplayPort
 	  displays and adapters to be attached to the USB Type-C

Signature · 1 line

2.54.0

Heikki Krogerus

maintainer

2026-07-13 09:35 UTC #1 lore raw

Quoted 25 lines · Chaoyi Chen

From: Chaoyi Chen <[email protected]>
When TYPEC_DP_ALTMODE is enabled, DRM_AUX_HPD_BRIDGE is most likely also needed for embedded platforms. Select it when available.
Suggested-by Xu Yang <[email protected]>
Signed-off-by Chaoyi Chen <[email protected]>
---
Changes in v3:
- Link to v2: https://lore.kernel.org/all/[email protected]/
- Use the same "select" as v1 to make things simple.
Changes in v2:
- Link to v1: https://lore.kernel.org/all/[email protected]/
- Change "select" to "imply".
---
 drivers/usb/typec/altmodes/Kconfig | 1 +
 1 file changed, 1 insertion(+)
drivers/usb/typec/altmodes/Kconfig +0 -0
index 7867fa7c405d..b054c0b6a8d4 100644

drivers/usb/typec/altmodes/Kconfig menu "USB Type-C Alternate Mode drivers" · line 8

Quoted 4 lines

drivers/usb/typec/altmodes/Kconfig +1 -0

@@ -5,6 +5,7 @@ menu "USB Type-C Alternate Mode drivers"
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
 	depends on DRM
+	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE && OF

Is there really no way of making this into a dependency? Doesn't this, or something like it not work:

        depends on (DRM_AUX_HPD_BRIDGE && DRM_BRIDGE && OF) || !DRM_AUX_HPD_BRIDGE

Thanks,

Quoted 5 lines

drivers/usb/typec/altmodes/Kconfig +0 -0

 	help
 	  DisplayPort USB Type-C Alternate Mode allows DisplayPort
 	  displays and adapters to be attached to the USB Type-C

Signature · 1 line

2.54.0

Signature · 1 line

heikki

Chaoyi Chen

2026-07-15 08:09 UTC #2 lore raw

Hi Heikki,

Quoted 34 lines · Heikki Krogerus

Quoted 25 lines · Chaoyi Chen
From: Chaoyi Chen <[email protected]>
When TYPEC_DP_ALTMODE is enabled, DRM_AUX_HPD_BRIDGE is most likely also needed for embedded platforms. Select it when available.
Suggested-by Xu Yang <[email protected]>
Signed-off-by Chaoyi Chen <[email protected]>
---
Changes in v3:
- Link to v2: https://lore.kernel.org/all/[email protected]/
- Use the same "select" as v1 to make things simple.
Changes in v2:
- Link to v1: https://lore.kernel.org/all/[email protected]/
- Change "select" to "imply".
---
 drivers/usb/typec/altmodes/Kconfig | 1 +
 1 file changed, 1 insertion(+)
drivers/usb/typec/altmodes/Kconfig +0 -0
index 7867fa7c405d..b054c0b6a8d4 100644
drivers/usb/typec/altmodes/Kconfig menu "USB Type-C Alternate Mode drivers" · line 8
Quoted 4 lines
drivers/usb/typec/altmodes/Kconfig +1 -0
@@ -5,6 +5,7 @@ menu "USB Type-C Alternate Mode drivers"
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
 	depends on DRM
+	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE && OF
Is there really no way of making this into a dependency? Doesn't this, or something like it not work:

Quoted 2 lines

        depends on (DRM_AUX_HPD_BRIDGE && DRM_BRIDGE && OF) || !DRM_AUX_HPD_BRIDGE

I think Xu originally wanted to select this item directly, since it wasn't visible in the menu and there was nowhere to select it on some platforms.

Quoted 8 lines

Thanks,
Quoted 5 lines
drivers/usb/typec/altmodes/Kconfig +0 -0
 	help
 	  DisplayPort USB Type-C Alternate Mode allows DisplayPort
 	  displays and adapters to be attached to the USB Type-C
Signature · 1 line
2.54.0

Signature · 2 lines

Best, 
Chaoyi

Heikki Krogerus

maintainer

2026-07-16 08:44 UTC #3 lore raw

Quoted 37 lines · Chaoyi Chen

Hi Heikki,
Quoted 34 lines · Heikki Krogerus
Quoted 25 lines · Chaoyi Chen
From: Chaoyi Chen <[email protected]>
When TYPEC_DP_ALTMODE is enabled, DRM_AUX_HPD_BRIDGE is most likely also needed for embedded platforms. Select it when available.
Suggested-by Xu Yang <[email protected]>
Signed-off-by Chaoyi Chen <[email protected]>
---
Changes in v3:
- Link to v2: https://lore.kernel.org/all/[email protected]/
- Use the same "select" as v1 to make things simple.
Changes in v2:
- Link to v1: https://lore.kernel.org/all/[email protected]/
- Change "select" to "imply".
---
 drivers/usb/typec/altmodes/Kconfig | 1 +
 1 file changed, 1 insertion(+)
drivers/usb/typec/altmodes/Kconfig +0 -0
index 7867fa7c405d..b054c0b6a8d4 100644
drivers/usb/typec/altmodes/Kconfig menu "USB Type-C Alternate Mode drivers" · line 8
Quoted 4 lines
drivers/usb/typec/altmodes/Kconfig +1 -0
@@ -5,6 +5,7 @@ menu "USB Type-C Alternate Mode drivers"
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
 	depends on DRM
+	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE && OF
Is there really no way of making this into a dependency? Doesn't this, or something like it not work:

Quoted 5 lines

Quoted 2 lines
        depends on (DRM_AUX_HPD_BRIDGE && DRM_BRIDGE && OF) || !DRM_AUX_HPD_BRIDGE
I think Xu originally wanted to select this item directly, since it wasn't visible in the menu and there was nowhere to select it on some platforms.

But now it is user selectable, no?

Thanks,

Signature · 1 line

heikki

Chaoyi Chen

2026-07-16 10:47 UTC #4 lore raw

Quoted 38 lines · Heikki Krogerus

Quoted 37 lines · Chaoyi Chen
Hi Heikki,
Quoted 34 lines · Heikki Krogerus
Quoted 25 lines · Chaoyi Chen
From: Chaoyi Chen <[email protected]>
When TYPEC_DP_ALTMODE is enabled, DRM_AUX_HPD_BRIDGE is most likely also needed for embedded platforms. Select it when available.
Suggested-by Xu Yang <[email protected]>
Signed-off-by Chaoyi Chen <[email protected]>
---
Changes in v3:
- Link to v2: https://lore.kernel.org/all/[email protected]/
- Use the same "select" as v1 to make things simple.
Changes in v2:
- Link to v1: https://lore.kernel.org/all/[email protected]/
- Change "select" to "imply".
---
 drivers/usb/typec/altmodes/Kconfig | 1 +
 1 file changed, 1 insertion(+)
drivers/usb/typec/altmodes/Kconfig +0 -0
index 7867fa7c405d..b054c0b6a8d4 100644
drivers/usb/typec/altmodes/Kconfig menu "USB Type-C Alternate Mode drivers" · line 8
Quoted 4 lines
drivers/usb/typec/altmodes/Kconfig +1 -0
@@ -5,6 +5,7 @@ menu "USB Type-C Alternate Mode drivers"
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
 	depends on DRM
+	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE && OF
Is there really no way of making this into a dependency? Doesn't this, or something like it not work:

Quoted 7 lines

Quoted 5 lines
Quoted 2 lines
        depends on (DRM_AUX_HPD_BRIDGE && DRM_BRIDGE && OF) || !DRM_AUX_HPD_BRIDGE
I think Xu originally wanted to select this item directly, since it wasn't visible in the menu and there was nowhere to select it on some platforms.
But now it is user selectable, no?

No, currently it needs to be explicitly selected in Kconfig, and it is not visible to the user.

Quoted 3 lines

Thanks,

Signature · 2 lines

Best, 
Chaoyi

Heikki Krogerus

maintainer Reviewed-by

2026-07-16 11:53 UTC #5 lore raw

Quoted 42 lines · Chaoyi Chen

Quoted 41 lines · Heikki Krogerus
Quoted 40 lines · Chaoyi Chen
Hi Heikki,
Quoted 36 lines · Heikki Krogerus
Quoted 25 lines · Chaoyi Chen
From: Chaoyi Chen <[email protected]>
When TYPEC_DP_ALTMODE is enabled, DRM_AUX_HPD_BRIDGE is most likely also needed for embedded platforms. Select it when available.
Suggested-by Xu Yang <[email protected]>
Signed-off-by Chaoyi Chen <[email protected]>
---
Changes in v3:
- Link to v2: https://lore.kernel.org/all/[email protected]/
- Use the same "select" as v1 to make things simple.
Changes in v2:
- Link to v1: https://lore.kernel.org/all/[email protected]/
- Change "select" to "imply".
---
 drivers/usb/typec/altmodes/Kconfig | 1 +
 1 file changed, 1 insertion(+)
drivers/usb/typec/altmodes/Kconfig +0 -0
index 7867fa7c405d..b054c0b6a8d4 100644
drivers/usb/typec/altmodes/Kconfig menu "USB Type-C Alternate Mode drivers" · line 8
Quoted 4 lines
drivers/usb/typec/altmodes/Kconfig +1 -0
@@ -5,6 +5,7 @@ menu "USB Type-C Alternate Mode drivers"
 config TYPEC_DP_ALTMODE
 	tristate "DisplayPort Alternate Mode driver"
 	depends on DRM
+	select DRM_AUX_HPD_BRIDGE if DRM_BRIDGE && OF
Is there really no way of making this into a dependency? Doesn't this, or something like it not work:
        depends on (DRM_AUX_HPD_BRIDGE && DRM_BRIDGE && OF) || !DRM_AUX_HPD_BRIDGE

Quoted 7 lines

Quoted 4 lines
Quoted 2 lines
I think Xu originally wanted to select this item directly, since it wasn't visible in the menu and there was nowhere to select it on some platforms.
But now it is user selectable, no?
No, currently it needs to be explicitly selected in Kconfig, and it is not visible to the user.

Okay, yet another Kconfig option with dependencies that's not user selectable. Meaning, everything that selects that option has to carry the same dependencies, and hope that if those dependencies ever change they are updated everywhere. :(

I still don't like this at all, but let's go with it for now.

Reviewed-by Heikki Krogerus <[email protected]>

Thanks,

Signature · 1 line

heikki