Re: [PATCH] mmc: mmci: Break IRQ status loop when all zero

From: Ulf Hansson <ulf.hansson@linaro.org>
To: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-mmc@vger.kernel.org
Subject: Re: [PATCH] mmc: mmci: Break IRQ status loop when all zero
Date: Thu, 21 Apr 2022 15:54:39 +0200	[thread overview]
Message-ID: <CAPDyKFo_SLzycgMYytfizkqRcEzYYB4epp1UD6Gp6ZczYB_MKw@mail.gmail.com> (raw)
In-Reply-To: <20220416224549.627623-1-linus.walleij@linaro.org>

On Sun, 17 Apr 2022 at 00:47, Linus Walleij <linus.walleij@linaro.org> wrote:
>
> We iterate an extra time through the IRQ status handling
> loop despite nothing had fired. Enabling the debug prints:
>
> mmci-pl18x 80005000.mmc: op 01 arg 00000000 flags 000000e1
> mmci-pl18x 80005000.mmc: irq0 (data+cmd) 00000001
> mmci-pl18x 80005000.mmc: irq0 (data+cmd) 00000000
> mmci-pl18x 80005000.mmc: op 01 arg 40ff8080 flags 000000e1
> mmci-pl18x 80005000.mmc: irq0 (data+cmd) 00000001
> mmci-pl18x 80005000.mmc: irq0 (data+cmd) 00000000
>
> It is pointless to loop through the function when status
> is zero. Just break the loop if the status is zero.
>
> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Applied for next, thanks!

Kind regards
Uffe

> ---
>  drivers/mmc/host/mmci.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/drivers/mmc/host/mmci.c b/drivers/mmc/host/mmci.c
> index 45b8608c935c..f3cf3152a397 100644
> --- a/drivers/mmc/host/mmci.c
> +++ b/drivers/mmc/host/mmci.c
> @@ -1619,6 +1619,8 @@ static irqreturn_t mmci_irq(int irq, void *dev_id)
>
>         do {
>                 status = readl(host->base + MMCISTATUS);
> +               if (!status)
> +                       break;
>
>                 if (host->singleirq) {
>                         if (status & host->mask1_reg)
> --
> 2.35.1
>