The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 5c27ff5db1491a947264d6d4e4cbe43ae6535bae Mon Sep 17 00:00:00 2001

From: Sergei Shtylyov sergei.shtylyov@cogentembedded.com Date: Mon, 18 Feb 2019 20:45:40 +0300 Subject: [PATCH] mmc: tmio_mmc_core: don't claim spurious interrupts

I have encountered an interrupt storm during the eMMC chip probing (and the chip finally didn't get detected). It turned out that U-Boot left the DMAC interrupts enabled while the Linux driver didn't use those. The SDHI driver's interrupt handler somehow assumes that, even if an SDIO interrupt didn't happen, it should return IRQ_HANDLED. I think that if none of the enabled interrupts happened and got handled, we should return IRQ_NONE -- that way the kernel IRQ code recoginizes a spurious interrupt and masks it off pretty quickly...

Fixes: 7729c7a232a9 ("mmc: tmio: Provide separate interrupt handlers") Signed-off-by: Sergei Shtylyov sergei.shtylyov@cogentembedded.com Reviewed-by: Wolfram Sang wsa+renesas@sang-engineering.com Tested-by: Wolfram Sang wsa+renesas@sang-engineering.com Reviewed-by: Simon Horman horms+renesas@verge.net.au Cc: stable@vger.kernel.org Signed-off-by: Ulf Hansson ulf.hansson@linaro.org

diff --git a/drivers/mmc/host/tmio_mmc_core.c b/drivers/mmc/host/tmio_mmc_core.c index 085a0fab769c..41d79720e745 100644 --- a/drivers/mmc/host/tmio_mmc_core.c +++ b/drivers/mmc/host/tmio_mmc_core.c @@ -629,7 +629,7 @@ static bool __tmio_mmc_sdcard_irq(struct tmio_mmc_host *host, int ireg, return false; }

-static void __tmio_mmc_sdio_irq(struct tmio_mmc_host *host) +static bool __tmio_mmc_sdio_irq(struct tmio_mmc_host *host) { struct mmc_host *mmc = host->mmc; struct tmio_mmc_data *pdata = host->pdata; @@ -637,7 +637,7 @@ static void __tmio_mmc_sdio_irq(struct tmio_mmc_host *host) unsigned int sdio_status;

if (!(pdata->flags & TMIO_MMC_SDIO_IRQ)) - return; + return false;

status = sd_ctrl_read16(host, CTL_SDIO_STATUS); ireg = status & TMIO_SDIO_MASK_ALL & ~host->sdio_irq_mask; @@ -650,6 +650,8 @@ static void __tmio_mmc_sdio_irq(struct tmio_mmc_host *host)

if (mmc->caps & MMC_CAP_SDIO_IRQ && ireg & TMIO_SDIO_STAT_IOIRQ) mmc_signal_sdio_irq(mmc); + + return ireg; }

irqreturn_t tmio_mmc_irq(int irq, void *devid) @@ -668,9 +670,10 @@ irqreturn_t tmio_mmc_irq(int irq, void *devid) if (__tmio_mmc_sdcard_irq(host, ireg, status)) return IRQ_HANDLED;

- __tmio_mmc_sdio_irq(host); + if (__tmio_mmc_sdio_irq(host)) + return IRQ_HANDLED;

- return IRQ_HANDLED; + return IRQ_NONE; } EXPORT_SYMBOL_GPL(tmio_mmc_irq);