Re: [PATCH v2 00/11] Fix support for System Suspend for CS35L41 HDA

Takashi Iwai
2023-07-24T09:01:01Z

On Fri, 21 Jul 2023 17:18:05 +0200,
Stefan Binding wrote:
>
> There have been a couple of customer reports of intermittant issues after
> system resume, where sometimes the DSP firmware stops responding.
> Investigations into this issue show that there is a race between receiving
> a prepare from the HDA core, and the firmware reload which is started by
> the system resume. This can causes the Global Enable on the CS35L41 to be
> enabled during the firmware load, which can sometimes cause issues in the
> DSP.
>
> The existing system resume behaviour also did not resume the audio, if
> audio was previously playing when it was suspended.
> In addition, during investigation, it was found there were additional
> problems in the System Resume sequence, as well as the Playback sequence
> with External Boost, where the driver does not correctly follow its
> enable sequence for this mode. This can cause additional issues such as
> pops and clicks.
>
> This chain intends to correct the sequences for playback and system
> suspend/resume so that the driver: obeys the external boost enable sequence;
> resumes audio on system resume; and avoids the race condition on firmware
> load and playback during system resume.
>
> Changes since v1:
> - Split patch 1 into 2 separate patches
> - Combine Patches 6 and 9
>
> Stefan Binding (11):
> ALSA: cs35l41: Use mbox command to enable speaker output for external
> boost
> ALSA: cs35l41: Poll for Power Up/Down rather than waiting a fixed
> delay
> ALSA: hda: cs35l41: Check mailbox status of pause command after
> firmware load
> ALSA: hda: cs35l41: Ensure we correctly re-sync regmap before system
> suspending.
> ALSA: hda: cs35l41: Ensure we pass up any errors during system
> suspend.
> ALSA: hda: cs35l41: Move Play and Pause into separate functions
> ALSA: hda: hda_component: Add pre and post playback hooks to
> hda_component
> ALSA: hda: cs35l41: Use pre and post playback hooks
> ALSA: hda: cs35l41: Rework System Suspend to ensure correct call
> separation
> ALSA: hda: cs35l41: Add device_link between HDA and cs35l41_hda
> ALSA: hda: cs35l41: Ensure amp is only unmuted during playback

Applied all patches now to for-next branch.

thanks,

Takashi