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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 08:19:51 +0000 (10:19 +0200)
commitc7ed5c02e4101faef5e9d542aa3da4c4d63acaae
treec4f5346cd13ceebba8ac34752f57751c4cffdb3d
parentf0d3242a1211c2f12a6da93c97e6b2c4861aba88
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