[alsa-devel] [PATCH v2] ALSA: hda - program ICT bits to support HBR audio

[Pierre-Louis Bossart]

On 9/20/17 5:00 AM, Takashi Iwai wrote:
> On Wed, 20 Sep 2017 00:25:05 +0200,
> Pierre-Louis Bossart wrote:
>>
>> From: Sriram Periyasamy <sriramx.periyasamy at intel.com>
>>
>> On recent Intel platforms (Haswell, Broadwell, Skylake, ApolloLake,
>> KabyLake, ...), the IEC Coding Type (ICT) bitfield in the Digital
>> Converter Control #3 needs to be set explicitly for HDMI/DisplayPort
>> High Bit Rate (HBR) audio playback to work. This was not required in
>> earlier platforms when HBR was first introduced. The ICT bits are
>> defined in Section 7.3.3.9 of the HDaudio 1.0a specification.
>>
>> Since the ICT bitfield was not specified for HDAudio 1.0 devices
>> (before 2009), we only program it on machines more recent than
>> Haswell.
>>
>> We tested that this fix is not needed on Baytrail-I (MinnowBoard
>> Turbot) and believe by extension it also does not apply to Braswell.
>>
>> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=98797
>>
>> Signed-off-by: Sriram Periyasamy <sriramx.periyasamy at intel.com>
>> Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart at linux.intel.com>
>> Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty at intel.com>
>> ---
>> v2: move digi3 verb in Set section, only set ICT for haswell and newer
> 
> Applied now with a slight fix (moving *_SET_* definition to the right
> place).

Thanks Takashi. Not sure what happened since I have a clear memory of 
doing that change and making a note of it...