On Thu, 16 Jun 2011 15:41:23 +0200, Paul Rolland (=?UTF-8?B?44Od44O844Or44O744Ot44Op44Oz?=) rol@witbe.net wrote:
Hello,
I've just booted 3.0.0-rc3 on my machine, and I got that message : Jun 16 15:32:07 tux kernel: [drm] GMBUS timed out, falling back to bit banging on pin 5 [i915 gmbus dpb]
I've checked my logs, and I never got that with my previous 2.6.39.1 kernel, so that looks like something new to 3.x.
Attempting to use GMBUS when enabled for 3.0. It will have to be disabled again until the GMBUS/GPIO adapter aligns better with the i2c interface and doesn't cause a deadlock upon booting with the eeprom module.
In the meantime, if you have the time and inclination, you can help by working out under what conditions GMBUS fails. That info message is only generated after we write a message over GMBUS and receive no response. I've looked into one exchange that suggests that we may timeout if the monitor is disconnected. Do you have anything connected to what would be the first external output? Does the message go away if you boot with that connected/disconnected?
Should I report more details (and if so, which ones) or is that harmless (though I doubt kernel messages about a time out are harmless ;)
It's harmless in this case. Just a warning that the new hw driven method failed and we are now using the old CPU driven method. -Chris