radeon: add support for Custom EDID

Allows you to specify an edid per output from a file
to override what is detected by DDC.  Useful for
problematic monitors or KVM switches that block
DDC.  Specifying an EDID that is not compatible with
your monitor could damage your monitor so use with
caution.

agd5f: cache the custom edid at startup so we don't
have to read it from file every time the output is
queried.

1 files changed, 28 insertions, 0 deletions

diff --git a/man/radeon.man b/man/radeon.man
index 703fe1d7..62270fb9 100644
--- a/man/radeon.man
+++ b/man/radeon.man
@@ -302,6 +302,34 @@ for monitor detection. This is different from NoDDC option.
 The default value is
 .B off.
 .TP 
+.BI "Option \*qCustomEDID\*q \*q" string \*q
+Forces the X driver to use the EDID data specified in a file rather
+than the display's EDID. Also overrides DDC monitor detection.
+.br
+You may specify a semicolon separated list of output name and filename pairs.
+The output name is something like "VGA-0" or "DVI-0";
+consult the Xorg log for the supported output names of any given system.
+.br
+The file must contain a raw 128-byte EDID block, as captured by
+.B
+get-edid.
+.br
+For example:
+.B
+Option \*qCustomEDID\*q \*qVGA-0:/tmp/edid1.bin; DVI-0:/tmp/edid2.bin\*q
+will assign the EDID from the file /tmp/edid1.bin to the output device
+VGA-0, and the EDID from the file /tmp/edid2.bin to the output device
+DVI-0.
+.br
+Note that a output name must always be specified,
+even if only one EDID is specified.
+.br
+.B
+Caution:
+Specifying an EDID that doesn't exactly match your display may
+damage your hardware, as it allows the driver to specify timings beyond
+the capabilities of your display. Use with care.
+.TP 
 .BI "Option \*qPanelSize\*q \*q" "string" \*q
 Should only be used when driver cannot detect the correct panel size.
 Apply to both desktop (TMDS) and laptop (LVDS) digital panels.