On 07/16/2015 11:31 PM, David Henningsson wrote:
On 2015-07-16 17:14, Yang, Libin wrote:
-----Original Message----- From: David Henningsson [mailto:david.henningsson@canonical.com] Sent: Thursday, July 16, 2015 4:39 PM To: tiwai@suse.de; hui.wang@canonical.com; alsa-devel@alsa- project.org; Yang, Libin; Lin, Mengdong Cc: David Henningsson Subject: [PATCH v2] ALSA: hda - Fix Skylake codec timeout
When the controller is powered up but the HDMI codec is powered down on Skylake, the power well is turned off. When the codec is then powered up again, we need to poke the codec a little extra to make sure it wakes up. Otherwise we'll get sad "no response from codec" messages and broken audio.
Thanks for finding this issue.
Could you please give us you test case? We didn't meet such issue before. I would like do a full test on it.
The test case is:
- Install Ubuntu 15.04.
- Upgrade to kernel 4.1.
- Boot the new kernel.
Note: I believe Hui tested with 4.1 and got this error. In my case I have been running a hybrid kernel: Ubuntu 15.04, kernel 3.19.0-23.24 (which has a backported i915 driver), and then the alsa-daily DKMS on top of that.
I can email you off-list with details about the machine I tested it on, if you like.
Here is a dmesg log, it is generated on a skl laptop with drm-intel-nightly kernel (v4.2), searching the keyword "timeout" in the text, you will find lots of timeout errors.