Re: [PATCH v24 14/16] docs: describe virtio-sound capture options

[sashiko-bot@kernel.org]

Thank you for your contribution! Sashiko AI review found 2 potential
issues to consider:
- [Low] docs: kernel-parameters: wrong resume sequence for
  capture_pause_restart
- [Low] docs: kernel-parameters: changelog removal claim and misplaced
  capture notes
--

commit f206bce4fef897e65bfa607d98ee01bb4cbeb0fd
Author: Joonho Lee <mynameisjune111@gmail.com>

docs: describe virtio-sound capture options

This commit documents the virtio_snd.capture_packed_status and
virtio_snd.capture_pause_restart module parameters and the capture
buffer behavior in Documentation/admin-guide/kernel-parameters.txt.

> diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
> index e75344f4e0cde..8a9e062ac33f6 100644
> --- a/Documentation/admin-guide/kernel-parameters.txt
> +++ b/Documentation/admin-guide/kernel-parameters.txt
> @@ -8344,6 +8344,29 @@ Kernel parameters
>  
>  			Can be used multiple times for multiple devices.
>  
> +	virtio_snd.capture_packed_status= [HW,ALSA]
> +			Read an explicitly enabled packed status trailer after
> +			the returned capture data. The fixed status scatterlist is
> +			used by default.
> +			Format: <bool>
> +			Default: false.
> +
> +	virtio_snd.capture_pause_restart= [HW,ALSA]
> +			Stop and release the stream when pausing capture. On
> +			resume, send SET_PARAMS, PREPARE, and START. With this
> +			option disabled, pause uses STOP and START while retaining
> +			the prepared stream.
> +			Format: <bool>
> +			Default: false.

[Severity: Low]
Does resume from pause actually send SET_PARAMS when
virtio_snd.capture_pause_restart is enabled?

On SNDRV_PCM_TRIGGER_PAUSE_RELEASE, virtsnd_pcm_pause_restart_start()
with resume == true calls virtsnd_pcm_pause_prepare() to send
VIRTIO_SND_R_PCM_PREPARE and then sends VIRTIO_SND_R_PCM_START, without
calling virtsnd_pcm_dev_set_params().

> +
> +			Capture always receives into request-owned buffers, then
> +			appends validated, frame-aligned audio to the ALSA ring in
> +			request order. A valid short response is retained. Empty
> +			responses are tolerated only during bounded startup or for
> +			requests already in flight at STOP or PAUSE. This uses up
> +			to one PCM buffer of temporary memory and copies returned
> +			audio into the ALSA ring.

[Severity: Low]
This paragraph describes unconditional capture behavior rather than the
virtio_snd.capture_pause_restart= parameter, but it is indented inside
that parameter's entry after its Format and Default lines.  In addition,
the commit message says "Remove the earlier opt-in staging and
short/empty-response descriptions", which seems to describe a change
against an earlier revision of the series rather than the baseline tree.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261111000543.28550-1-mynameisjune111@gmail.com?part=14