linux-kernel - Re: [PATCH v1 01/11] ALSA: cs35l41: Use mbox command to enable speaker output for external boost

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Message-ID: <56e50829-b93d-48ef-9691-5c78229a4b5c@sirena.org.uk>
Date:   Thu, 20 Jul 2023 15:11:04 +0100
From:   Mark Brown <broonie@...nel.org>
To:     Stefan Binding <sbinding@...nsource.cirrus.com>
Cc:     Jaroslav Kysela <perex@...ex.cz>, Takashi Iwai <tiwai@...e.com>,
        alsa-devel@...a-project.org, linux-kernel@...r.kernel.org,
        patches@...nsource.cirrus.com
Subject: Re: [PATCH v1 01/11] ALSA: cs35l41: Use mbox command to enable
 speaker output for external boost

On Thu, Jul 20, 2023 at 02:31:37PM +0100, Stefan Binding wrote:
> To enable the speaker output in external boost mode, 2 registers must
> be set, one after another. The longer the time between the writes of
> the two registers, the more likely, and more loudly a pop may occur.
> To minimize this, an mbox command can be used to allow the firmware
> to perform this action, minimizing any delay between write, thus
> minimizing any pop or click as a result. The old method will remain
> when running without firmware.

> In addition, to ensure the chip has correctly powered up or down,
> the driver will now poll a register, rather than wait a fixed delay.

That should probably be a separate patch.

Acked-by: Mark Brown <broonie@...nel.org>

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