@@ -2154,13 +2154,30 @@ static irqreturn_t sdhci_irq(int irq, void *dev_id)
mmc_hostname(host->mmc), intmask);
if (intmask & (SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE)) {
+ u32 present = sdhci_readl(host, SDHCI_PRESENT_STATE) &
+ SDHCI_CARD_PRESENT;
+
+ /*
+ * There is a observation on i.mx esdhc. INSERT bit will be
+ * immediately set again when it gets cleared, if a card is
+ * inserted. We have to mask the irq to prevent interrupt
+ * storm which will freeze the system. And the REMOVE gets
+ * the same situation.
+ *
+ * More testing are needed here to ensure it works for other
+ * platforms though.
+ */
+ sdhci_mask_irqs(host, present ? SDHCI_INT_CARD_INSERT :
+ SDHCI_INT_CARD_REMOVE);
+ sdhci_unmask_irqs(host, present ? SDHCI_INT_CARD_REMOVE :
+ SDHCI_INT_CARD_INSERT);
+
sdhci_writel(host, intmask & (SDHCI_INT_CARD_INSERT |
- SDHCI_INT_CARD_REMOVE), SDHCI_INT_STATUS);
+ SDHCI_INT_CARD_REMOVE), SDHCI_INT_STATUS);
+ intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);
tasklet_schedule(&host->card_tasklet);
}
- intmask &= ~(SDHCI_INT_CARD_INSERT | SDHCI_INT_CARD_REMOVE);
-
if (intmask & SDHCI_INT_CMD_MASK) {
sdhci_writel(host, intmask & SDHCI_INT_CMD_MASK,
SDHCI_INT_STATUS);
The issue was initially found by Eric Benard as below. http://permalink.gmane.org/gmane.linux.ports.arm.kernel/108031 Not sure about other SDHCI based controller, but on Freescale eSDHC, the SDHCI_INT_CARD_INSERT bits will be immediately set again when it gets cleared, if a card is inserted. The driver need to mask the irq to prevent interrupt storm which will freeze the system. And the SDHCI_INT_CARD_REMOVE gets the same situation. The patch fixes the problem based on the initial idea from Eric Benard. Signed-off-by: Shawn Guo <shawn.guo@linaro.org> Cc: Eric Benard <eric@eukrea.com> --- drivers/mmc/host/sdhci.c | 23 ++++++++++++++++++++--- 1 files changed, 20 insertions(+), 3 deletions(-)