Re: [PATCH] mmc: sdhci-xenon: fix 1.8v regulator stabilization

[Marcin Wojtas]

wt., 15 gru 2020 o 09:04 Adrian Hunter <adrian.hunter@xxxxxxxxx> napisał(a):
>
> On 11/12/20 4:16 pm, Marcin Wojtas wrote:
> > From: Alex Leibovich <alexl@xxxxxxxxxxx>
> >
> > Automatic Clock Gating is a feature used for the power
> > consumption optimisation. It turned out that
> > during early init phase it may prevent the stable voltage
> > switch to 1.8V - due to that on some platfroms an endless
>
> platfroms -> platforms
>
> > printout in dmesg can be observed:
> > "mmc1: 1.8V regulator output did not became stable"
> > Fix the problem by disabling the ACG at very beginning
> > of the sdhci_init and let that be enabled later.
> >
> > Fixes: 3a3748dba881 ("mmc: sdhci-xenon: Add Marvell Xenon SDHC core functionality")
> > Signed-off-by: Alex Leibovich <alexl@xxxxxxxxxxx>
> > Signed-off-by: Marcin Wojtas <mw@xxxxxxxxxxxx>
> > Cc: stable@xxxxxxxxxxxxxxx
>
> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
>

Thank you, I'll repost right away with the typos correction.

Best regards,
Marcin

> > ---
> >  drivers/mmc/host/sdhci-xenon.c | 7 ++++++-
> >  1 file changed, 6 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-xenon.c b/drivers/mmc/host/sdhci-xenon.c
> > index c67611fdaa8a..4b05f6fdefb4 100644
> > --- a/drivers/mmc/host/sdhci-xenon.c
> > +++ b/drivers/mmc/host/sdhci-xenon.c
> > @@ -168,7 +168,12 @@ static void xenon_reset_exit(struct sdhci_host *host,
> >       /* Disable tuning request and auto-retuning again */
> >       xenon_retune_setup(host);
> >
> > -     xenon_set_acg(host, true);
> > +     /*
> > +      * The ACG should be turned off at the early init time, in order
> > +      * to solve a possile issues with the 1.8V regulator stabilization.
>
> a possile -> possible
>
> > +      * The feature is enabled in later stage.
> > +      */
> > +     xenon_set_acg(host, false);
> >
> >       xenon_set_sdclk_off_idle(host, sdhc_id, false);
> >
> >
>