1 files changed, 16 insertions, 5 deletions

diff --git a/drivers/net/wireless/libertas/if_sdio.c b/drivers/net/wireless/libertas/if_sdio.c
index a7b5cb0c2753..224e9853c480 100644
--- a/drivers/net/wireless/libertas/if_sdio.c
+++ b/drivers/net/wireless/libertas/if_sdio.c
@@ -907,7 +907,7 @@ static void if_sdio_interrupt(struct sdio_func *func)
         card = sdio_get_drvdata(func);
 
         cause = sdio_readb(card->func, IF_SDIO_H_INT_STATUS, &ret);
-        if (ret)
+        if (ret || !cause)
                 goto out;
 
         lbs_deb_sdio("interrupt: 0x%X\n", (unsigned)cause);
@@ -1008,10 +1008,6 @@ static int if_sdio_probe(struct sdio_func *func,
         if (ret)
                 goto release;
 
-        ret = sdio_claim_irq(func, if_sdio_interrupt);
-        if (ret)
-                goto disable;
-
         /* For 1-bit transfers to the 8686 model, we need to enable the
          * interrupt flag in the CCCR register. Set the MMC_QUIRK_LENIENT_FN0
          * bit to allow access to non-vendor registers. */
@@ -1083,6 +1079,21 @@ static int if_sdio_probe(struct sdio_func *func,
                 card->rx_unit = 0;
 
         /*
+         * Set up the interrupt handler late.
+         *
+         * If we set it up earlier, the (buggy) hardware generates a spurious
+         * interrupt, even before the interrupt has been enabled, with
+         * CCCR_INTx = 0.
+         *
+         * We register the interrupt handler late so that we can handle any
+         * spurious interrupts, and also to avoid generation of that known
+         * spurious interrupt in the first place.
+         */
+        ret = sdio_claim_irq(func, if_sdio_interrupt);
+        if (ret)
+                goto disable;
+
+        /*
          * Enable interrupts now that everything is set up
          */
         sdio_writeb(func, 0x0f, IF_SDIO_H_INT_MASK, &ret);