On Mon, May 17, 2010 at 3:16 AM, Zhenyu Wang <<a href="mailto:zhenyuw@linux.intel.com">zhenyuw@linux.intel.com</a>> wrote: > > On 2010.05.15 03:46:35 +0200, Mikael Öhman wrote: > > Hello. > > I was wondering if it was possible to send audio over displayport using a Core > > i5 661 (Clarkdale) IGP. > > I have seen some charts indicating that the hardware actually supports it, but > > I'm not even sure if I should ask here or perhaps to some ALSA mailing list. > > On google I have only found things related to DP->HMDI with audio, which I > > don't need. > > Yeah, we're looking into that actually. And current difficult is how to > identify the DP sink device really has audio support. One is to use EDID > CEA ext 'basic audio' feature, and another I've tried is to parse DPCD > downstream device type. Unfortunately the DP monitors we have now don't > have sane indication for them all, so we don't have good hardware to verify > this (also tried windows driver but still failed with DP audio on it). > > Maybe we should just use EDID to determine whether enable audio or not. Xorg.log do contain some EDID output. I don't know what tool i should use otherwise. get-edid gives me some errors (and it tries to parse my second monitor only, I need to disconnect it when i get home). It doesn't give me any more information anyway. (II) intel(0): EDID for output DP3 (II) intel(0): Manufacturer: NEC Model: 677a Serial#: 0 (II) intel(0): Year: 2009 Week: 49 (II) intel(0): EDID Version: 1.4 (II) intel(0): Digital Display Input (II) intel(0): 8 bits per channel (II) intel(0): Digital interface is DisplayPort snip (II) intel(0): Monitor name: EA231WMi (II) intel(0): Serial No: 9Z104746NB (II) intel(0): Number of EDID sections to follow: 1 (II) intel(0): EDID (in hex): (II) intel(0): 00ffffffffffff0038a37a6700000000 (II) intel(0): 31130104a5331d78e2f805a4554d9d25 (II) intel(0): 125054bfef8081008140818081c09500 (II) intel(0): 9040b300a9c0023a801871382d40582c (II) intel(0): 4500fe1f1100001e000000fd00384c1f (II) intel(0): 5311000a202020202020000000fc0045 (II) intel(0): 41323331574d690a20202020000000ff (II) intel(0): 00395a3130343734364e420a202001a5 If i read the specification for EDID correctly, 01 would specify 1 extension block. The extension block doesn't seem to printed in Xorg.0.log > > > > > aplay only lists > > card 0: Intel [HDA Intel], device 0: ALC889 Analog [ALC889 Analog] > > card 0: Intel [HDA Intel], device 1: ALC889 Digital [ALC889 Digital] > > card 0: Intel [HDA Intel], device 3: INTEL HDMI 0 [INTEL HDMI 0] > > card 0: Intel [HDA Intel], device 7: INTEL HDMI 1 [INTEL HDMI 1] > > and naturally I've tried them all, with no sound. > > > > I'm using Debian unstable, and xserver-xorg-video-intel 2.11 (everything else > > also uptodate with Sid if that matters.) > > > > > > You may try to force 'has_audio' to true in intel_dp.c, and try with HDA > HDMI codec. Let me know if that'll work for you, and what's your monitor model? > I have a NEC EA231WMi I just accidentally found that my monitor had the option to select sound from DP (and I can't test it with any other equipment). I will test it be hardcoding has_audio=true tonight.