mmc: sdhci: Ignore unexpected CARD_INT interrupts
authorGabriel Krisman Bertazi <krisman@collabora.co.uk>
Mon, 16 Jan 2017 14:23:42 +0000 (12:23 -0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 9 Feb 2017 07:08:28 +0000 (08:08 +0100)
commit04eb7db25bb1bcf4ee1631d1099fc03308929c12
treefbf2b11f06c0a23d08d85cb9350ca4ae6d2cc6d8
parent1d88791d5ed5dae4ff8cbbf6147e90ff95d92ba9
mmc: sdhci: Ignore unexpected CARD_INT interrupts

commit 161e6d44a5e2d3f85365cb717d60e363171b39e6 upstream.

One of our kernelCI boxes hanged at boot because a faulty eSDHC device
was triggering spurious CARD_INT interrupts for SD cards, causing CMD52
reads, which are not allowed for SD devices.  This adds a sanity check
to the interruption path, preventing that illegal command from getting
sent if the CARD_INT interruption should be disabled.

This quirk allows that particular machine to resume boot despite the
faulty hardware, instead of getting hung dealing with thousands of
mishandled interrupts.

Suggested-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/mmc/host/sdhci.c