[PATCH v9 1/1] alsa: jack: implement software jack injection via debugfs

[Takashi Iwai]

On Wed, 27 Jan 2021 09:56:39 +0100,
Hui Wang wrote:
> 
> This change adds audio jack injection feature through debugfs, with
> this feature, we could validate alsa userspace changes by injecting
> plugin or plugout events to the non-phantom audio jacks.
> 
> With this change, the sound core will build the folders
> $debugfs_mount_dir/sound/cardN if SND_DEBUG and DEBUG_FS are enabled.
> And if users also enable the SND_JACK_INJECTION_DEBUG, the jack
> injection nodes will be built in the folder cardN like below:
> 
> $tree $debugfs_mount_dir/sound
> $debugfs_mount_dir/sound
> ├── card0
> │   ├── HDMI_DP_pcm_10_Jack
> │   │   ├── jackin_inject
> │   │   ├── kctl_id
> │   │   ├── mask_bits
> │   │   ├── status
> │   │   ├── sw_inject_enable
> │   │   └── type
> ...
> │   └── HDMI_DP_pcm_9_Jack
> │       ├── jackin_inject
> │       ├── kctl_id
> │       ├── mask_bits
> │       ├── status
> │       ├── sw_inject_enable
> │       └── type
> └── card1
>     ├── HDMI_DP_pcm_5_Jack
>     │   ├── jackin_inject
>     │   ├── kctl_id
>     │   ├── mask_bits
>     │   ├── status
>     │   ├── sw_inject_enable
>     │   └── type
>     ...
>     ├── Headphone_Jack
>     │   ├── jackin_inject
>     │   ├── kctl_id
>     │   ├── mask_bits
>     │   ├── status
>     │   ├── sw_inject_enable
>     │   └── type
>     └── Headset_Mic_Jack
>         ├── jackin_inject
>         ├── kctl_id
>         ├── mask_bits
>         ├── status
>         ├── sw_inject_enable
>         └── type
> 
> The nodes kctl_id, mask_bits, status and type are read-only, users
> could check jack or jack_kctl's information through them.
> 
> The nodes sw_inject_enable and jackin_inject are directly used for
> injection. The sw_inject_enable is read-write, users could check if
> software injection is enabled or not on this jack, and users could
> echo 1 or 0 to enable or disable software injection on this jack. Once
> the injection is enabled, the jack will not change by hardware events
> anymore, once the injection is disabled, the jack will restore the
> last reported hardware events to the jack. The jackin_inject is
> write-only, if the injection is enabled, users could echo 1 or 0 to
> this node to inject plugin or plugout events to this jack.
> 
> For the detailed usage information on these nodes, please refer to
> Documentation/sound/designs/jack-injection.rst.
> 
> Reviewed-by: Takashi Iwai <tiwai at suse.de>
> Reviewed-by: Jaroslav Kysela <perex at perex.cz>
> Reviewed-by: Kai Vehmanen <kai.vehmanen at linux.intel.com>
> Signed-off-by: Hui Wang <hui.wang at canonical.com>

Applied now.  Thanks.


Takashi