Re: [PATCH v2 03/11] mmc: mtk-sd: Re-store SDIO IRQs mask at system resume
From: Ulf Hansson
Date: Wed Sep 11 2019 - 08:07:14 EST
On Tue, 10 Sep 2019 at 00:29, Doug Anderson <dianders@xxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Sun, Sep 8, 2019 at 3:12 AM Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
> >
> > In cases when SDIO IRQs have been enabled, runtime suspend is prevented by
> > the driver. However, this still means msdc_runtime_suspend|resume() gets
> > called during system suspend/resume, via pm_runtime_force_suspend|resume().
> >
> > This means during system suspend/resume, the register context of the mtk-sd
> > device most likely loses its register context, even in cases when SDIO IRQs
> > have been enabled.
> >
> > To re-enable the SDIO IRQs during system resume, the mtk-sd driver
> > currently relies on the mmc core to re-enable the SDIO IRQs when it resumes
> > the SDIO card, but this isn't the recommended solution. Instead, it's
> > better to deal with this locally in the mtk-sd driver, so let's do that.
> >
> > Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
> > ---
> > drivers/mmc/host/mtk-sd.c | 3 +++
> > 1 file changed, 3 insertions(+)
> >
> > diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
> > index 6946bb040a28..ae7688098b7b 100644
> > --- a/drivers/mmc/host/mtk-sd.c
> > +++ b/drivers/mmc/host/mtk-sd.c
> > @@ -2408,6 +2408,9 @@ static void msdc_save_reg(struct msdc_host *host)
> > } else {
> > host->save_para.pad_tune = readl(host->base + tune_reg);
> > }
> > +
> > + if (sdio_irq_claimed(host->mmc))
> > + __msdc_enable_sdio_irq(host, 1);
> > }
> >
> > static void msdc_restore_reg(struct msdc_host *host)
>
> I don't personally have a Mediatek device setup to test this patch on.
> If it's super urgent I could try to track down one and try to set it
> up, but hopefully it's easier for someone else...
>
> That being said, from code inspection it seems like you should be
> adding your code to msdc_restore_reg(), not to msdc_save_reg(). Am I
> confused?
No, you are absolutely correct, my bad. Thanks a lot for spotting this!
Kind regards
Uffe