[alsa-devel] [PATCH] ASoC: fsl_ssi: remove explicit register defaults

[Fabio Estevam]

On Mon, Jan 18, 2016 at 5:07 PM, Maciej S. Szmigiero
<mail at maciej.szmigiero.name> 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.
>
> However, the cache needs to be fully populated at probe
> time to avoid non-atomic allocations during register
> access.
>
> Special case here is imx21-class SSI, since
> according to datasheet it don't have SACC{ST,EN,DIS}
> regs.
>
> 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 at maciej.szmigiero.name>

Tested-by: Fabio Estevam <fabio.estevam at nxp.com>