linux-kernel - Re: [PATCH RESEND 1/2] mfd: madera: Add reset as part of resume

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Message-ID: <20201104154005.GO4488@dell>
Date:   Wed, 4 Nov 2020 15:40:05 +0000
From:   Lee Jones <lee.jones@...aro.org>
To:     Charles Keepax <ckeepax@...nsource.cirrus.com>
Cc:     linux-kernel@...r.kernel.org, patches@...nsource.cirrus.com
Subject: Re: [PATCH RESEND 1/2] mfd: madera: Add reset as part of resume

On Tue, 27 Oct 2020, Charles Keepax wrote:

> The DCVDD supply does not always power down when the CODEC enters
> suspend, for example shared regulators or always-on regulators. In
> these cases if a register is written back to the default value whilst
> the CODEC is in suspend that register will retain the previous value.
> As DCVDD never powered down, the register retains its old value and
> as the cache sync only synchronises registers that differ from the
> default the new value is never written out.
> 
> Ensure the registers are in the expected state after suspend by always
> resetting the CODEC on resume. This also has the benefit of being
> recommended by the datasheet for DCVDD supplies that take longer than
> 2mS to rise.
> 
> Signed-off-by: Charles Keepax <ckeepax@...nsource.cirrus.com>
> ---
>  drivers/mfd/madera-core.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)

Applied, thanks.

-- 
Lee Jones [李琼斯]
Senior Technical Lead - Developer Services
Linaro.org │ Open source software for Arm SoCs
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