[PATCH] Avoid needless loop in sdhci_irq()

From: Alexey Neyman
Date: Tue Nov 05 2013 - 14:57:26 EST


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>
---
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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