I have a TV that appears to not provide proper EDID info to the HDMI or DVI
ports of my Intel DH77DF motherboard. I received some pointers from this
list that pointed me in the direction of creating my own EDID file and I
now have a binary blob that matches what the service manual says is the
proper EDID info.
But I am unable to get the drm_kms_helper module to load and use this file.
My relevant kernel config options are.
CONFIG_DRM_KMS_HELPER=m
CONFIG_DRM_LOAD_EDID_FIRMWARE=y
my relevant kernel command line contains:
video=card0-HDMI-A-1:e
drm_kms_helper.edid_firmware=card0-HDMI-A-1:edid/lg42lb9df_hdmi1.edid
The edid file:
# ls -al /lib/firmware/edid/lg42lb9df_hdmi1.edid
-rw-r--r-- 1 root root 256 Oct 16 05:46 /lib/firmware/edid/lg42lb9df_hdmi1.edid
connector info from /sys/class/drm/
card0 card0-DP-1 card0-DP-2 card0-DP-3 card0-HDMI-A-1 card0-HDMI-A-2
card0-HDMI-A-3 card0-VGA-1 controlD64 version
And I don't really understand why I have 3 entries for the one hdmi port?
Nor do I really understand _exactly_ how to define the connector in my
kernel command line or which of the 3 connectors from /sys I should be
using. I've tried different variants. Ie. card0-HDMI-A-1and HDMI-A-1.
The results in the kernel log file remain:
[ 1.879654] drm_kms_helper: Unknown parameter `edid'
I assume I am doing something wrong but I have put some debug printks in
kernel/params.c that shows me every call made to it and it's params. It is
entered many times and I see a sequence to in the log file. As an example,
the last one to call with params before drm_kms_helper is "late" and here
are my debug prints for it:
[ 0.840206] parse_args: Entered for late
[ 0.840207] parse_args: doing = late
[ 0.840208] parse_args: args =
root=/dev/disk/by-id/ata-INTEL_SSDSC2CW060A3_CVCV205106EB060AGN-part4
video=1024x768
resume=/dev/disk/by-id/ata-INTEL_SSDSC2CW060A3_CVCV205106EB060AGN-part3
splash=silent quiet vga=0x37e irqpoll video=card0-HDMI-A-1:e
drm_kms_helper.edid_firmware=card0-HDMI-A-1:edid/lg42lb9df_hdmi1.edid
[ 0.840209] parse_args: params =
[ 0.840210] parse_args: num = 174
[ 0.840210] parse_args: min_level = 7
[ 0.840211] parse_args: max_level = 7
Now when it gets to drm_kms_helper this is what I get and this is certainly
screwed up, I just don't know why.
[ 1.879648] parse_args: Entered for drm_kms_helper
[ 1.879648] parse_args: doing = drm_kms_helper
[ 1.879649] parse_args: args = edid
\xffffff86\xffffffe2\xfffffff8h\xffffff89\xffffff86\xffffffc0\xffffff80\xffffffff\xffffffff?\xffffffe2\xfffffff8T\xffffff86\xffffffe2\xfffffff88\xffffff89\xffffff86\xffffffc0\xffffffa4\xffffffff\xffffffffd\xffffff86\xffffffe2\xfffffff8
[ 1.879650] parse_args: num = 2
[ 1.879651] parse_args: min_level = -32768
[ 1.879651] parse_args: max_level = 32767
[ 1.879653]
\xffffff86\xffffffe2\xfffffff8h\xffffff89\xffffff86\xffffffc0\xffffff80\xffffffff\xffffffff?\xffffffe2\xfffffff8T\xffffff86\xffffffe2\xfffffff88\xffffff89\xffffff86\xffffffc0\xffffffa4\xffffffff\xffffffffd\xffffff86\xffffffe2\xfffffff8,
num=2, min_level=-32768, max_level=32767
Then finally:
[ 1.879654] drm_kms_helper: Unknown parameter `edid'
The additional printks I inserted into kernel/params.c:
if (*args)
pr_debug("doing %s, parsing ARGS: '%s'\n", doing, args);
+ if (*args) {
+ printk("\nparse_args: Entered for %s\n", doing);
+ printk("parse_args: doing = %s\n", doing);
+ printk("parse_args: args = %s\n", args);
+ printk("parse_args: params = %s\n", params);
+ printk("parse_args: num = %d\n", num);
+ printk("parse_args: min_level = %d\n",min_level);
+ printk("parse_args: max_level = %d\n", max_level);
+ }
while (*args) {
This is using a vanilla 3.6.2 kernel. Any help would be appreciated.
Regards
Mark
