[RFC/PATCH 0/2] mmc: sdhci: Workaround Intel Merrifield issue for HS200

From: David Cohen
Date: Tue Oct 29 2013 - 13:54:38 EST


SDHCI used to work well on Intel Merrifield until this patch was applied:

commit 156e14b126ffb6f040bc6f1aff3c51077e42a744
Author: Giuseppe CAVALLARO <peppe.cavallaro@xxxxxx>
Date: Wed Jun 12 08:16:38 2013 +0200

mmc: sdhci: fix caps2 for HS200

Although the HC supports HS200 (eMMC) the caps2 are always zero; this
means there's no way to use the super speed mode (when init the card).

If the HC support SDR104, for SD3.0, so it also supports HS200 for eMMC
and this patch just sets the MMC_CAP2_HS200 in the host caps2 field.

Looks like there is a hw issue with unknown root cause so far.

Is it acceptable to have the quirk I'm proposing to workaround the issue?

Br, David Cohen

David Cohen (2):
mmc: sdhci: add quirk for broken HS200 support
mmc: sdhci-pci: add broken HS200 quirk for Intel Merrifield

drivers/mmc/host/sdhci-pci.c | 1 +
drivers/mmc/host/sdhci.c | 3 ++-
include/linux/mmc/sdhci.h | 2 ++
3 files changed, 5 insertions(+), 1 deletion(-)


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