[PATCH] mmc: sdhci: Avoid needless loop while handling SDIO interrupts in sdhci_irq()

[Alexey Neyman]

Ignore Card Interrupt bit in the interrupt status if we already know that
mmc_signal_sdio_irq() is going to be called at the end of sdhci_irq(). This
avoids a needless loop in sdhci_irq() repeatedly reading interrupt status
and doing nothing.

Signed-off-by: Alexey Neyman <stilor@xxxxxxx>
Acked-by: Dong Aisheng <b29396@xxxxxxxxxxxxx>
---
 drivers/mmc/host/sdhci.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
index 7a7fb4f..a83cd1b 100644
--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2491,6 +2491,14 @@ again:
 	result = IRQ_HANDLED;
 
 	intmask = sdhci_readl(host, SDHCI_INT_STATUS);
+
+	/*
+	 * If we know we'll call the driver to signal SDIO IRQ, disregard
+	 * further indications of Card Interrupt in the status to avoid a
+	 * needless loop.
+	 */
+	if (cardint)
+		intmask &= ~SDHCI_INT_CARD_INT;
 	if (intmask && --max_loops)
 		goto again;
 out:
-- 
1.8.4.1

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