[PATCH] ALSA: hda/hdmi: packet buffer index must be set before reading value

[Takashi Iwai]

On Fri, 11 Dec 2020 14:16:13 +0100,
Kai Vehmanen wrote:
> 
> The check for infoframe transmit status in hdmi_infoframe_uptodate()
> makes the assumption that packet buffer index is set to zero.
> 
> Align code with specification and explicitly set the index before
> AC_VERB_GET_HDMI_DIP_XMIT. The packet index setting affects both
> DIP-Data and DIP-XmitCtrl verbs.
> 
> There are no known cases where the old implementation has caused driver
> to work incorrectly. This change is purely based on code review against
> the specification (HDA spec rev1.0a).
> 
> Signed-off-by: Kai Vehmanen <kai.vehmanen at linux.intel.com>

Currently there is no other place to change DIP index, i.e. it's
always zero, and the bug wouldn't hit, but it's better to be addressed
beforehand, indeed.

Applied now.  Thanks.


Takashi