Re: [PATCH v3 1/2] ALSA: hda: cs35l41: Support mute notifications for CS35L41 HDA

From: Takashi Iwai
Date: Wed Sep 20 2023 - 02:58:27 EST


On Tue, 19 Sep 2023 16:22:39 +0200,
Stefan Binding wrote:
>
> From: Vitaly Rodionov <vitalyr@xxxxxxxxxxxxxxxxxxxxx>
>
> Some laptops require a hardware based mute system, where when a hotkey
> is pressed, it forces the amp to be muted.
>
> For CS35L41, when the hotkey is pressed, an acpi notification is sent
> to the CS35L41 Device Node. The driver needs to handle this notification
> and call a _DSM function to retrieve the mute state.
>
> Since the amp is only muted during playback, the driver will only mute
> or unmute if playback is occurring, otherwise it will save the mute
> state for when playback starts.
>
> Only one handler can be registered for the acpi notification, but all
> amps need to receive that notification, we can register a single handler
> inside the Realtek HDA driver, so that it can then notify through the
> component framework.
>
> Signed-off-by: Vitaly Rodionov <vitalyr@xxxxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Stefan Binding <sbinding@xxxxxxxxxxxxxxxxxxxxx>

The patch is a bit lengthy. I'd split the binding of patch_realtek.c
into another patch. That part is fairly generic.

> --- a/sound/pci/hda/patch_realtek.c
> +++ b/sound/pci/hda/patch_realtek.c
(snip)
> +static void comp_acpi_device_notify(acpi_handle handle, u32 event, void *data)
> +{
> + struct hda_codec *cdc = data;
> + struct alc_spec *spec = cdc->spec;
> + int i;
> +
> + codec_info(cdc, "ACPI Notification %d\n", event);
> +
> + for (i = 0; i < HDA_MAX_COMPONENTS; i++) {
> + if (spec->comps[i].dev && spec->comps[i].acpi_notify)
> + spec->comps[i].acpi_notify(acpi_device_handle(spec->comps[i].adev), event,
> + spec->comps[i].dev);
> + }
> +}

This function should be in #ifdef CONFIG_ACPI, too.


thanks,

Takashi