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mmc: core: Fix init of SD cards reporting an invalid VDD range
authorUlf Hansson <ulf.hansson@linaro.org>
Tue, 27 Aug 2019 08:10:43 +0000 (10:10 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 6 Sep 2019 08:18:17 +0000 (10:18 +0200)
commite2f1509fca476d763d94eb0026b28c22ab110688
tree98cfccd7d011e62a6f06623b7de6ad11aeddae16
parent12a897daa78b640bcdfd6422bf2d697c442549e1
mmc: core: Fix init of SD cards reporting an invalid VDD range

commit 72741084d903e65e121c27bd29494d941729d4a1 upstream.

The OCR register defines the supported range of VDD voltages for SD cards.
However, it has turned out that some SD cards reports an invalid voltage
range, for example having bit7 set.

When a host supports MMC_CAP2_FULL_PWR_CYCLE and some of the voltages from
the invalid VDD range, this triggers the core to run a power cycle of the
card to try to initialize it at the lowest common supported voltage.
Obviously this fails, since the card can't support it.

Let's fix this problem, by clearing invalid bits from the read OCR register
for SD cards, before proceeding with the VDD voltage negotiation.

Cc: stable@vger.kernel.org
Reported-by: Philip Langdale <philipl@overt.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Philip Langdale <philipl@overt.org>
Tested-by: Philip Langdale <philipl@overt.org>
Tested-by: Manuel Presnitz <mail@mpy.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/mmc/core/sd.c