Re: [PATCH v2] mmc: sdhci-of-arasan: fix set_clock when a phy is supported

[Shawn Lin]

å 2016/5/4 16:35, Heiko Stuebner åé:
> Am Mittwoch, 4. Mai 2016, 09:48:55 schrieb Shawn Lin:
> > å 2016/4/28 18:38, Ulf Hansson åé:
> > > On 28 April 2016 at 10:38, Shawn Lin <shawn.lin@xxxxxxxxxxxxxx> wrote:
> > > > commit 61b914eb81f8 ("mmc: sdhci-of-arasan: add phy support for
> > > > sdhci-of-arasan") introduce phy support for arasan. According to
> > > > the vendor's databook, we should make sure the phy is in poweroff
> > > > status before we configure the clk stuff. Otherwise it may cause
> > > > some IO sample timing issues from the test. And we don't need this
> > > > extra operation while running in low performance mode since phy
> > > > doesn't trigger sampling block.
> > > >
> > > > Signed-off-by: Shawn Lin <shawn.lin@xxxxxxxxxxxxxx>
> > >
> > > Thanks, applied for next!
> >
> > Thanks for applying v2 but, could you please drop it and applied v3
> > I just send :) .
> > Because v2 introduces a bug. Set_clock callback will be
> > called under the protection of spinlock in sdhci_do_set_ios. However
> > PHY APIs need mutex which fails the kernel's debug check
> >
> > BUG: sleeping function called from invalid context at
> > kernel/locking/mutex.c
>
> I think in general you will need to provide a follow-up patch instead of
> replacing the old version, as Ulf might not want to restructure an already
> published branch (depends on the maintainer), especially as already other
> stuff is on top of your patch [0].

Aha.. yes I see other patches on top of mine now. Thanks for reminding
it.

Ulf, would you mind that I send a new patch to fix it, or you are prone
to restructure the next?

> Heiko
>
> [0]
> https://git.linaro.org/people/ulf.hansson/mmc.git/shortlog/refs/heads/next
>
>
>
>
> > > Kind regards
> > > Uffe
> > >
> > > > ---
> > > >
> > > > Changes in v2:
> > > > - change commit msg title to indicate it's a fix
> > > > - fix a typo in commmit msg
> > > >
> > > >  drivers/mmc/host/sdhci-of-arasan.c | 20 +++++++++++++++++++-
> > > >  1 file changed, 19 insertions(+), 1 deletion(-)
> > > >
> > > > diff --git a/drivers/mmc/host/sdhci-of-arasan.c
> > > > b/drivers/mmc/host/sdhci-of-arasan.c index 2e482b1..20b859e 100644
> > > > --- a/drivers/mmc/host/sdhci-of-arasan.c
> > > > +++ b/drivers/mmc/host/sdhci-of-arasan.c
> > > > @@ -55,8 +55,26 @@ static unsigned int
> > > > sdhci_arasan_get_timeout_clock(struct sdhci_host *host)>>
> > > >         return freq;
> > > >
> > > >  }
> > > >
> > > > +static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned
> > > > int clock) +{
> > > > +       struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > > > +       struct sdhci_arasan_data *sdhci_arasan =
> > > > sdhci_pltfm_priv(pltfm_host); +       bool ctrl_phy = false;
> > > > +
> > > > +       if (clock > MMC_HIGH_52_MAX_DTR &&
> > > > (!IS_ERR(sdhci_arasan->phy)))
> > > > +               ctrl_phy = true;
> > > > +
> > > > +       if (ctrl_phy)
> > > > +               phy_power_off(sdhci_arasan->phy);
> > > > +
> > > > +       sdhci_set_clock(host, clock);
> > > > +
> > > > +       if (ctrl_phy)
> > > > +               phy_power_on(sdhci_arasan->phy);
> > > > +}
> > > > +
> > > >
> > > >  static struct sdhci_ops sdhci_arasan_ops = {
> > > >
> > > > -       .set_clock = sdhci_set_clock,
> > > > +       .set_clock = sdhci_arasan_set_clock,
> > > >
> > > >         .get_max_clock = sdhci_pltfm_clk_get_max_clock,
> > > >         .get_timeout_clock = sdhci_arasan_get_timeout_clock,
> > > >         .set_bus_width = sdhci_set_bus_width,
> > > >
> > > > --
> > > > 2.3.7
> > > >
> > > >
> > > > --
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> > > > the body of a message to majordomo@xxxxxxxxxxxxxxx
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--
Best Regards
Shawn Lin