From: Trac Hoang trac.hoang@broadcom.com
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.
This change applies only to the Cygnus platform.
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 --- drivers/mmc/host/sdhci-iproc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/mmc/host/sdhci-iproc.c b/drivers/mmc/host/sdhci-iproc.c index 9d12c06c7fd6..9d4071c41c94 100644 --- a/drivers/mmc/host/sdhci-iproc.c +++ b/drivers/mmc/host/sdhci-iproc.c @@ -196,7 +196,8 @@ static const struct sdhci_ops sdhci_iproc_32only_ops = { };
static const struct sdhci_pltfm_data sdhci_iproc_cygnus_pltfm_data = { - .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK, + .quirks = SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK | + SDHCI_QUIRK_NO_HISPD_BIT, .quirks2 = SDHCI_QUIRK2_ACMD23_BROKEN | SDHCI_QUIRK2_HOST_OFF_CARD_ON, .ops = &sdhci_iproc_32only_ops, };