[alsa-devel] [PATCH] ALSA: hda - Fix error accessing non-existent node for Realtek codecs

[Takashi Iwai]

At Mon, 15 Jul 2013 10:20:52 +0200,
David Henningsson wrote:
> 
> A recent commit caused my hda-emu based test tool to complain about
> accessing nodes that don't exist. This simple test works around this.
> 
> Signed-off-by: David Henningsson <david.henningsson at canonical.com>
> ---
>  sound/pci/hda/patch_realtek.c |    3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> I don't have ALC5505 hardware here, no alsa-info to look at, and I don't know
> what it is. Therefore it would be good with some confirmation that this patch
> does not break such hardware, which could be the case if the Realtek codec
> breaks the HDA spec by having "hidden" nodes.

It seems that ALC5505 itself doesn't appear in the codec information
but it appears transparent to the real codec behind it.  So the node
0x51 doesn't exist in the widget list of the codec, and your  patch
will break.

we may need to patch hda-emu instead...


Takashi

> 
> diff --git a/sound/pci/hda/patch_realtek.c b/sound/pci/hda/patch_realtek.c
> index 8bd2261..ca73f10 100644
> --- a/sound/pci/hda/patch_realtek.c
> +++ b/sound/pci/hda/patch_realtek.c
> @@ -3844,7 +3844,8 @@ static int patch_alc269(struct hda_codec *codec)
>  		break;
>  	}
>  
> -	if (snd_hda_codec_read(codec, 0x51, 0, AC_VERB_PARAMETERS, 0) == 0x10ec5505) {
> +	if (codec->num_nodes > 0x51 &&
> +	    snd_hda_codec_read(codec, 0x51, 0, AC_VERB_PARAMETERS, 0) == 0x10ec5505) {
>  		spec->has_alc5505_dsp = true;
>  		spec->init_hook = alc5505_dsp_init;
>  	}
> -- 
> 1.7.9.5
>