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 for <linuxppc-dev@lists.ozlabs.org>; Mon, 11 Jan 2016 08:36:35 +1100 (AEDT)
Subject: Re: [PATCH 3/3] ASoC: fsl_ssi: remove register defaults
To: "Maciej S. Szmigiero" <mail@maciej.szmigiero.name>,
 "alsa-devel@alsa-project.org" <alsa-devel@alsa-project.org>
Cc: Nicolin Chen <nicoleotsuka@gmail.com>, Xiubo Li <Xiubo.Lee@gmail.com>,
 Liam Girdwood <lgirdwood@gmail.com>, Mark Brown <broonie@kernel.org>,
 "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
 linux-kernel <linux-kernel@vger.kernel.org>,
 Fabio Estevam <festevam@gmail.com>
References: <5677107C.60904@maciej.szmigiero.name>
From: Timur Tabi <timur@tabi.org>
Message-ID: <5692CEE2.2040504@tabi.org>
Date: Sun, 10 Jan 2016 15:36:34 -0600
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Maciej S. Szmigiero wrote:
> There is no guarantee that on fsl_ssi module load
> SSI registers will have their power-on-reset values.
>
> In fact, if the driver is reloaded the values in
> registers will be whatever they were set to previously.
>
> This fixes hard lockup on fsl_ssi module reload,
> at least in AC'97 mode.
>
> Fixes: 05cf237972fe ("ASoC: fsl_ssi: Add driver suspend and resume to support MEGA Fast")
>
> Signed-off-by: Maciej S. Szmigiero<mail@maciej.szmigiero.name>

Acked-by: Timur Tabi <timur@tabi.org>

I'm surprised that we're actually encouraging drivers to contain 
hard-coded register values.