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mmc: sdhci-iproc: Set NO_HISPD bit to fix HS50 data hold time problem
authorTrac Hoang <trac.hoang@broadcom.com>
Thu, 9 May 2019 17:24:27 +0000 (10:24 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 31 May 2019 13:46:01 +0000 (06:46 -0700)
commit5b69ceee219699aac77b761efa484f9d9a8cd4b5
tree4ea1bf4cfe7002a023107483d8f8700376a5a3c2
parent227e01537baf7d8d5b14bd889540d5eb649ab66c
mmc: sdhci-iproc: Set NO_HISPD bit to fix HS50 data hold time problem

commit ec0970e0a1b2c807c908d459641a9f9a1be3e130 upstream.

The iproc host eMMC/SD controller hold time does not meet the
specification in the HS50 mode.  This problem can be mitigated
by disabling the HISPD bit; thus forcing the controller output
data to be driven on the falling clock edges rather than the
rising clock edges.

Stable tag (v4.12+) chosen to assist stable kernel maintainers so that
the change does not produce merge conflicts backporting to older kernel
versions. In reality, the timing bug existed since the driver was first
introduced but there is no need for this driver to be supported in kernel
versions that old.

Cc: stable@vger.kernel.org # v4.12+
Signed-off-by: Trac Hoang <trac.hoang@broadcom.com>
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
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-iproc.c