On Wed, Jul 6, 2011 at 11:39 AM, Alex Deucher alexdeucher@gmail.com wrote:
On Wed, Jul 6, 2011 at 6:09 AM, reimth@googlemail.com wrote:
From: Thomas Reim rdratlos@yahoo.co.uk
Some integrated ATI Radeon chipset implementations with add-on HDMI card (e. g. Asus M2A-VM HDMI) indicate the availability of a DDC even when the add-on card is not plugged in or HDMI is disabled in BIOS setup. In this case, drm_get_edid() and drm_edid_block_valid() periodically dump data and kernel errors into system log files and onto terminals. For these chipsets DDC probing is extended by a check for a correct EDID header. Only in case a valid EDID header is also found, the (HDMI) connector will be used by the Radeon driver. This prevents the kernel driver from useless flooding of logs and terminal sessions with EDID dumps and error messages. This patch adds a flag 'requires_extended_probe' to the radeon_connector structure. In function radeon_connector_needs_extended_probe() this flag can be set on a chipset family/vendor/connector type specific basis. In addition, function drm_edid_header_is_valid() has been added for EDID header check and function radeon_ddc_probe() has been adapted to perform extended DDC probing if required by the connector's flag.
Tested for kernel 2.35, 2.38 and 3.0 on Asus M2A-VM HDMI board
Once it's ready, just add: Cc: stable@kernel.org to the commit message and it will go into the stable kernels as well. Might want to mention the bug report in your commit message as well. Just a couple comments below. With those fixed:
Reviewed-by: Alex Deucher alexdeucher@gmail.com
We also may want to revert 4a9a8b71e12d41abb71c4e741bff524f016cfef4 once this patch goes in, otherwise we may remove the ddc bus unnecessarily on some systems.
Alex