[alsa-devel] [PATCH v2] ALSA: hda - hdmi: Fix channel map switch not taking effect

[Takashi Iwai]

At Mon,  7 Oct 2013 19:24:52 +0300,
Anssi Hannula wrote:
> 
> Currently hdmi_setup_audio_infoframe() reprograms the HDA channel
> mapping only when the infoframe is not up-to-date or the non-PCM flag
> has changed.
> 
> However, when just the channel map has been changed, the infoframe may
> still be up-to-date and non-PCM flag may not have changed, so the new
> channel map is not actually programmed into the HDA codec.
> 
> Notably, this failing case is also always triggered when the device is
> already in a prepared state and a new channel map is configured while
> changing only the channel positions (for example, plain
> "speaker-test -c2 -m FR,FL").
> 
> Fix that by always programming the channel map in
> hdmi_setup_audio_infoframe(). Tested on Intel HDMI.
> 
> Signed-off-by: Anssi Hannula <anssi.hannula at iki.fi>
> Cc: <stable at vger.kernel.org>
> ---
> 
> Here is a simpler version of the map switch fix.

Thanks, applied now.

The for-linus branch including this fix was merged back to for-next
branch, too, so you can use for-next branch for the further
development.


Takashi

> 
>  sound/pci/hda/patch_hdmi.c | 18 ++++++++----------
>  1 file changed, 8 insertions(+), 10 deletions(-)
> 
> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> index 7ea0245..50173d4 100644
> --- a/sound/pci/hda/patch_hdmi.c
> +++ b/sound/pci/hda/patch_hdmi.c
> @@ -937,6 +937,14 @@ static void hdmi_setup_audio_infoframe(struct hda_codec *codec,
>  	}
>  
>  	/*
> +	 * always configure channel mapping, it may have been changed by the
> +	 * user in the meantime
> +	 */
> +	hdmi_setup_channel_mapping(codec, pin_nid, non_pcm, ca,
> +				   channels, per_pin->chmap,
> +				   per_pin->chmap_set);
> +
> +	/*
>  	 * sizeof(ai) is used instead of sizeof(*hdmi_ai) or
>  	 * sizeof(*dp_ai) to avoid partial match/update problems when
>  	 * the user switches between HDMI/DP monitors.
> @@ -947,20 +955,10 @@ static void hdmi_setup_audio_infoframe(struct hda_codec *codec,
>  			    "pin=%d channels=%d\n",
>  			    pin_nid,
>  			    channels);
> -		hdmi_setup_channel_mapping(codec, pin_nid, non_pcm, ca,
> -					   channels, per_pin->chmap,
> -					   per_pin->chmap_set);
>  		hdmi_stop_infoframe_trans(codec, pin_nid);
>  		hdmi_fill_audio_infoframe(codec, pin_nid,
>  					    ai.bytes, sizeof(ai));
>  		hdmi_start_infoframe_trans(codec, pin_nid);
> -	} else {
> -		/* For non-pcm audio switch, setup new channel mapping
> -		 * accordingly */
> -		if (per_pin->non_pcm != non_pcm)
> -			hdmi_setup_channel_mapping(codec, pin_nid, non_pcm, ca,
> -						   channels, per_pin->chmap,
> -						   per_pin->chmap_set);
>  	}
>  
>  	per_pin->non_pcm = non_pcm;
> -- 
> 1.8.1.5
>