4.4-stable review patch. If anyone has any objections, please let me know.
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From: Sergei Shtylyov sergei.shtylyov@cogentembedded.com
commit 5c27ff5db1491a947264d6d4e4cbe43ae6535bae upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/mmc/host/tmio_mmc_pio.c | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-)
--- a/drivers/mmc/host/tmio_mmc_pio.c +++ b/drivers/mmc/host/tmio_mmc_pio.c @@ -716,7 +716,7 @@ irqreturn_t tmio_mmc_sdio_irq(int irq, v unsigned int sdio_status;
if (!(pdata->flags & TMIO_MMC_SDIO_IRQ)) - return IRQ_HANDLED; + return IRQ_NONE;
status = sd_ctrl_read16(host, CTL_SDIO_STATUS); ireg = status & TMIO_SDIO_MASK_ALL & ~host->sdcard_irq_mask; @@ -730,7 +730,7 @@ irqreturn_t tmio_mmc_sdio_irq(int irq, v if (mmc->caps & MMC_CAP_SDIO_IRQ && ireg & TMIO_SDIO_STAT_IOIRQ) mmc_signal_sdio_irq(mmc);
- return IRQ_HANDLED; + return IRQ_RETVAL(ireg); } EXPORT_SYMBOL(tmio_mmc_sdio_irq);
@@ -747,9 +747,7 @@ irqreturn_t tmio_mmc_irq(int irq, void * if (__tmio_mmc_sdcard_irq(host, ireg, status)) return IRQ_HANDLED;
- tmio_mmc_sdio_irq(irq, devid); - - return IRQ_HANDLED; + return tmio_mmc_sdio_irq(irq, devid); } EXPORT_SYMBOL(tmio_mmc_irq);