mmc: core: Prevent processing SDIO IRQs when none is claimed

In cases when MMC_CAP2_SDIO_IRQ_NOTHREAD is set, there is a minor window
for when the mmc host could call sdio_run_irqs(), while in fact an SDIO
func driver could have decided to released the SDIO IRQ via a call to
sdio_release_irq(). In this scenario, processing of the SDIO IRQs are done
even if there is none IRQ claimed, which is not what we want.

To prevent this from happen, close the window by validating that at least
one SDIO IRQs is claimed, before deciding to process them.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>

diff --git a/drivers/mmc/core/sdio_irq.c b/drivers/mmc/core/sdio_irq.c
index 6d4b72080d5124094afbde859b8fa9341c1f4e1f..44d9c86bd2d4baedf542ed9da75b1cf7321dd1ae 100644 (file)
--- a/drivers/mmc/core/sdio_irq.c
+++ b/drivers/mmc/core/sdio_irq.c
@@ -95,8 +95,10 @@ static int process_sdio_pending_irqs(struct mmc_host *host)
 void sdio_run_irqs(struct mmc_host *host)
 {
        mmc_claim_host(host);
-       host->sdio_irq_pending = true;
-       process_sdio_pending_irqs(host);
+       if (host->sdio_irqs) {
+               host->sdio_irq_pending = true;
+               process_sdio_pending_irqs(host);
+       }
        mmc_release_host(host);
 }
 EXPORT_SYMBOL_GPL(sdio_run_irqs);