Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Skip to content
Commit 9f7fbcd6 authored by Alex Deucher's avatar Alex Deucher Committed by Greg Kroah-Hartman
Browse files

drm/radeon: fix AVI infoframe generation

commit f100380ecd8287b0909d3c5694784adc46e78a4a upstream.

- remove adding 2 to checksum, this is incorrect.

This was incorrectly introduced in:
92db7f6c
http://lists.freedesktop.org/archives/dri-devel/2011-December/017717.html


However, the off by 2 was due to adding the version twice.
From the examples in the URL above:

[Rafał Miłecki][RV620] fglrx:
0x7454: 00 A8 5E 79     R600_HDMI_VIDEOINFOFRAME_0
0x7458: 00 28 00 10     R600_HDMI_VIDEOINFOFRAME_1
0x745C: 00 48 00 28     R600_HDMI_VIDEOINFOFRAME_2
0x7460: 02 00 00 48     R600_HDMI_VIDEOINFOFRAME_3
===================
(0x82 + 0x2 + 0xD) + 0x1F8 = 0x289
-0x289 = 0x77

However, the payload sum is not 0x1f8, it's 0x1f6.
00 + A8 + 5E + 00 +
00 + 28 + 00 + 10 +
00 + 48 + 00 + 28 +
00 + 48 =
0x1f6

Bits 25:24 of HDMI_VIDEOINFOFRAME_3 are the packet version, not part
of the payload.  So the total would be:
(0x82 + 0x2 + 0xD) + 0x1f6 = 0x287
-0x287 = 0x79

- properly emit the AVI infoframe version.  This was not being
emitted previous which is probably what caused the issue above.

This should fix blank screen when HDMI audio is enabled on
certain monitors.

Signed-off-by: default avatarAlex Deucher <alexander.deucher@amd.com>
Cc: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent ef0cfe2f
Loading
Loading
Loading
Loading
0% Loading or .
You are about to add 0 people to the discussion. Proceed with caution.
Please register or to comment