mmc: bcm2835: Recover from MMC_SEND_EXT_CSD
authorPhil Elwell <phil@raspberrypi.org>
Sun, 11 Nov 2018 20:23:54 +0000 (21:23 +0100)
committerUlf Hansson <ulf.hansson@linaro.org>
Mon, 17 Dec 2018 07:26:24 +0000 (08:26 +0100)
commit07d405769afea5718529fc9e341f0b13b3189b6f
tree2bb61491884fe35eb2c67e837bd4965df6bf5118
parentf6000a4eb34e6462bc0dd39809c1bb99f9633269
mmc: bcm2835: Recover from MMC_SEND_EXT_CSD

If the user issues an "mmc extcsd read", the SD controller receives
what it thinks is a SEND_IF_COND command with an unexpected data block.
The resulting operations leave the FSM stuck in READWAIT, a state which
persists until the MMC framework resets the controller, by which point
the root filesystem is likely to have been unmounted.

A less heavyweight solution is to detect the condition and nudge the
FSM by asserting the (self-clearing) FORCE_DATA_MODE bit.

Link: https://github.com/raspberrypi/linux/issues/2728
Signed-off-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Acked-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
drivers/mmc/host/bcm2835.c