lkml.org 
[lkml]   [2019]   [Sep]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH 05/11] mmc: core: Clarify sdio_irq_pending flag for MMC_CAP2_SDIO_IRQ_NOTHREAD
On Thu, 5 Sep 2019 at 02:34, Matthias Kaehlcke <mka@chromium.org> wrote:
>
> On Tue, Sep 03, 2019 at 04:22:01PM +0200, Ulf Hansson wrote:
> > In the single SDIO IRQ handler case, the sdio_irq_pending flag is used to
> > avoid reading the SDIO_CCCR_INTx register and instead immediately call the
> > SDIO func's >irq_handler() callback.
> >
> > To clarify the use behind the flag for the MMC_CAP2_SDIO_IRQ_NOTHREAD case,
> > let's set the flag from inside sdio_signal_irq(), rather from
> > sdio_run_irqs(). Moreover, let's also reset the flag when the SDIO IRQ have
> > been properly processed.
> >
> > Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
> > ---
> > drivers/mmc/core/sdio_irq.c | 9 ++++++---
> > 1 file changed, 6 insertions(+), 3 deletions(-)
> >
> > diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c
> > index f75043266984..0962a4357d54 100644
> > --- a/drivers/mmc/core/sdio_irq.c
> > +++ b/drivers/mmc/core/sdio_irq.c
> > @@ -59,6 +59,7 @@ static int process_sdio_pending_irqs(struct mmc_host *host)
> > {
> > struct mmc_card *card = host->card;
> > int i, ret, count;
> > + bool sdio_irq_pending = host->sdio_irq_pending;
> > unsigned char pending;
> > struct sdio_func *func;
> >
> > @@ -66,13 +67,16 @@ static int process_sdio_pending_irqs(struct mmc_host *host)
> > if (mmc_card_suspended(card))
> > return 0;
> >
> > + /* Clear the flag to indicate that we have processed the IRQ. */
> > + host->sdio_irq_pending = false;
> > +
>
> It's not entirely true that we have processed the IRQ,
> the sdio_get_pending_irqs() below could fail and we'd return. However
> I guess if it comes to that we are in a pretty bad shape already and
> the value of the flag doesn't really matter.

Yes, that's my view as well.

>
> > /*
> > * Optimization, if there is only 1 function interrupt registered
> > * and we know an IRQ was signaled then call irq handler directly.
> > * Otherwise do the full probe.
> > */
> > func = card->sdio_single_irq;
> > - if (func && host->sdio_irq_pending) {
> > + if (func && sdio_irq_pending) {
> > func->irq_handler(func);
> > return 1;
> > }
> > @@ -110,7 +114,6 @@ static void sdio_run_irqs(struct mmc_host *host)
> > {
> > mmc_claim_host(host);
> > if (host->sdio_irqs) {
> > - host->sdio_irq_pending = true;
> > process_sdio_pending_irqs(host);
> > if (host->ops->ack_sdio_irq)
> > host->ops->ack_sdio_irq(host);
> > @@ -128,6 +131,7 @@ void sdio_irq_work(struct work_struct *work)
> >
> > void sdio_signal_irq(struct mmc_host *host)
> > {
> > + host->sdio_irq_pending = true;
> > queue_delayed_work(system_wq, &host->sdio_irq_work, 0);
> > }
> > EXPORT_SYMBOL_GPL(sdio_signal_irq);
> > @@ -173,7 +177,6 @@ static int sdio_irq_thread(void *_host)
> > if (ret)
> > break;
> > ret = process_sdio_pending_irqs(host);
> > - host->sdio_irq_pending = false;
> > mmc_release_host(host);
> >
> > /*
>
> Reviewed-by: Matthias Kaehlcke <mka@chromium.org>

Thanks!

Kind regards
Uffe

\
 
 \ /
  Last update: 2019-09-05 09:31    [W:0.084 / U:3.972 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site