On Mon, 04 Apr 2011 08:08:40 -0700, Keith Packard <[email protected]> wrote: > On Mon, 4 Apr 2011 07:26:44 +0100, Chris Wilson <[email protected]> > wrote: > > > Following the fix to reset the GMBUS controller after a NAK, we finally > > utilize the 0xa0 probe for a CRT connection. And discover that it is > > useless as it simply detects the presence of the controller and not the > > actual monitor. Given that we already probe 0x50 prior to performing the > > EDID retrieval, we can simply remove the redundant probe to 0xa0. > > I don't understand -- are you saying that there is additional hardware > somewhere in the machine responding to I2C transactions on the monitor's > DDC bus?
Yes. I'm saying that that the controller accepts a write to port 0xa0. > And if so, how was this extra transaction breaking things? The GMBUS > reset patch should only have an effect when there are failed > transactions, not successful ones, and then it should only cause future > transactions to fail, not succeed. Besides, the 0xA0 transaction looks > like the first one on the bus. We do several i2c xfers before CRT. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/intel-gfx
