[alsa-devel] [PATCH 3/3] ALSA: hda - hdmi: Notify userspace when ELD control changes

[Takashi Iwai]

At Mon, 18 Feb 2013 14:11:13 +0100,
David Henningsson wrote:
> 
> Since ELD sometimes becomes available a while after we have detected
> presence, we need to be able to listen for changes on the ELD control.
> 
> Signed-off-by: David Henningsson <david.henningsson at canonical.com>
> ---
>  sound/pci/hda/patch_hdmi.c |   10 ++++++++++
>  1 file changed, 10 insertions(+)
> 
> diff --git a/sound/pci/hda/patch_hdmi.c b/sound/pci/hda/patch_hdmi.c
> index 9236cdb..d3b1a93 100644
> --- a/sound/pci/hda/patch_hdmi.c
> +++ b/sound/pci/hda/patch_hdmi.c
> @@ -74,6 +74,7 @@ struct hdmi_spec_per_pin {
>  
>  	struct hda_codec *codec;
>  	struct hdmi_eld sink_eld;
> +	struct snd_kcontrol *eld_ctl;
>  	struct delayed_work work;
>  	int repoll_count;
>  	bool non_pcm;
> @@ -406,6 +407,7 @@ static int hdmi_create_eld_ctl(struct hda_codec *codec, int pin_idx,
>  	if (err < 0)
>  		return err;
>  
> +	spec->pins[pin_idx].eld_ctl = kctl;
>  	return 0;
>  }
>  
> @@ -1175,6 +1177,7 @@ static void hdmi_present_sense(struct hdmi_spec_per_pin *per_pin, int repoll)
>  	 */
>  	int present = snd_hda_pin_sense(codec, pin_nid);
>  	bool eld_valid = false;
> +	bool old_eld_valid = eld->eld_valid;
>  
>  	memset(eld, 0, offsetof(struct hdmi_eld, eld_buffer));
>  
> @@ -1196,6 +1199,13 @@ static void hdmi_present_sense(struct hdmi_spec_per_pin *per_pin, int repoll)
>  					   msecs_to_jiffies(300));
>  		}
>  	}
> +
> +	if (eld->eld_valid != old_eld_valid && per_pin->eld_ctl) {
> +		snd_ctl_notify(codec->bus->card,
> +			       SNDRV_CTL_EVENT_MASK_VALUE | SNDRV_CTL_EVENT_MASK_INFO,
> +			       &per_pin->eld_ctl->id);
> +	}

This notification should be skipped when the pin sensing is requeued.


Takashi