renegade-project/linux-next
2
0
Fork 0
mirror of https://github.com/edk2-porting/linux-next.git synced 2025-01-04 03:33:58 +08:00
Code

drm_dp_cec: add note about good MegaChips 2900 CEC support

Browse Source 
A big problem with DP CEC-Tunneling-over-AUX is that it is tricky
to find adapters with a chipset that supports this AND where the
manufacturer actually connected the HDMI CEC line to the chipset.

Add a mention of the MegaChips 2900 chipset which seems to support
this feature well.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180827075820.41109-3-hverkuil@xs4all.nl
This commit is contained in:
Hans Verkuil 2018-08-27 09:58:17 +02:00
parent 5ce70c799a
commit 9bcf6d9868
1 changed files with 3 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
drivers/gpu/drm/drm_dp_cec.c
View File

@ -16,7 +16,9 @@
* here. Quite a few active (mini-)DP-to-HDMI or USB-C-to-HDMI adapters
* have a converter chip that supports CEC-Tunneling-over-AUX (usually the
* Parade PS176), but they do not wire up the CEC pin, thus making CEC
* useless.
* useless. Note that MegaChips 2900-based adapters appear to have good
* support for CEC tunneling. Those adapters that I have tested using
* this chipset all have the CEC line connected.
*
* Sadly there is no way for this driver to know this. What happens is
* that a /dev/cecX device is created that is isolated and unable to see