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: NTrac Hoang <trac.hoang@broadcom.com> Signed-off-by: NScott Branden <scott.branden@broadcom.com> Acked-by: NAdrian Hunter <adrian.hunter@intel.com> Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org> Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
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