[RFC 4/4] mmc: sdhci-msm: Handle unexpected interrupt case on enabling legacy IRQs on CQE halt

From: Ritesh Harjani
Date: Wed Aug 30 2017 - 09:06:38 EST


There is a case when enabling the legacy IRQs and halting CQE is
resuling into a command response interrupt without any command in
progress. This patch handles such case here.

Error signature without this patch:-
mmc0: Got command interrupt 0x00000001 even though no command operation
was in progress.

Signed-off-by: Ritesh Harjani <riteshh@xxxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-msm.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/drivers/mmc/host/sdhci-msm.c b/drivers/mmc/host/sdhci-msm.c
index baa3409..8fdc2c0 100644
--- a/drivers/mmc/host/sdhci-msm.c
+++ b/drivers/mmc/host/sdhci-msm.c
@@ -1124,10 +1124,21 @@ void sdhci_msm_cqe_enable(struct mmc_host *mmc)
void sdhci_msm_cqe_disable(struct mmc_host *mmc, bool recovery)
{
struct sdhci_host *host = mmc_priv(mmc);
+ unsigned long flags;
+ u32 ctrl;

if (host->flags & SDHCI_USE_64_BIT_DMA)
host->desc_sz = 16;

+ spin_lock_irqsave(&host->lock, flags);
+
+ ctrl = sdhci_readl(host, SDHCI_INT_ENABLE);
+ ctrl |= SDHCI_INT_RESPONSE;
+ sdhci_writel(host, ctrl, SDHCI_INT_ENABLE);
+ sdhci_writel(host, SDHCI_INT_RESPONSE, SDHCI_INT_STATUS);
+
+ spin_unlock_irqrestore(&host->lock, flags);
+
sdhci_cqe_disable(mmc, recovery);
}

--
Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.