[i2c] Monitor's EDID not recognised

[Jean Delvare]

On Fri, 7 Mar 2008 22:37:36 +1100, Jeremy Murphy wrote:
> > I'm not sure why you would expect the EDID EEPROM on the ICH7 SMBus.
> > I've never seen an EDID EEPROM there. The EDID EEPROM is typically
> > accessed through an I2C bus on the graphics adapter. You will need a
> > driver for this. The binary nvidia X11 driver should work, the nvidiafb
> > framebuffer driver should work as well (that's what I am using myself).
> > After loading the driver, 2 or 3 additional I2C buses should be listed
> > by "i2cdetect -l" (don't forget to load i2c-dev beforehand), and
> > decode-edid.pl (or the more user-friendly ddcmon script) should find
> > the EDID on one of them.
> 
> I'm using nvidia's binary driver v169.07, and yes, the nvidia I2C buses are 
> there.  i2cdetect -l:
> 
> i2c-3   i2c             NVIDIA i2c adapter                      I2C adapter
> i2c-2   i2c             NVIDIA i2c adapter                      I2C adapter
> i2c-1   i2c             NVIDIA i2c adapter                      I2C adapter
> i2c-0   smbus           SMBus I801 adapter at 0400              SMBus adapter
> 
> However, decode-edid.pl and ddcmon both report that an EDID EEPROM is not 
> found.

Please provide the output of:
i2cdetect 1
i2cdetect 2
i2cdetect 3

Either there is no EDID EEPROM connected at all (some monitors don't
have them, in particular older models) or it has a format different
from what the scripts expect.

If anything shows up at 0x50 with i2cdetect, please provide a dump
using i2cdump (rmmod eeprom first.)

-- 
Jean Delvare