mmc: Prevent 1.8V switch for SD hosts that don't support UHS modes.
authorAl Cooper <acooper@gmail.com>
Fri, 16 Mar 2012 19:54:17 +0000 (15:54 -0400)
committerBen Hutchings <ben@decadent.org.uk>
Wed, 10 Oct 2012 02:31:11 +0000 (03:31 +0100)
commit26fb1ba1baf9fe555ff2918e027cef78ee3f54d0
treeec760a8092ca921c9a746ff50f682610b3f2c71b
parent96947d2b77943563c5b40916be376a89ee632aa9
mmc: Prevent 1.8V switch for SD hosts that don't support UHS modes.

commit 4188bba0e9e7ba58d231b528df495666f2742b74 upstream.

The driver should not try to switch to 1.8V when the SD 3.0 host
controller does not have any UHS capabilities bits set (SDR50, DDR50
or SDR104). See page 72 of "SD Specifications Part A2 SD Host
Controller Simplified Specification Version 3.00" under
"1.8V Signaling Enable". Instead of setting SDR12 and SDR25 in the host
capabilities data structure for all V3.0 host controllers, only set them
if SDR104, SDR50 or DDR50 is set in the host capabilities register. This
will prevent the switch to 1.8V later.

Signed-off-by: Al Cooper <acooper@gmail.com>
Acked-by: Arindam Nath <arindam.nath@amd.com>
Acked-by: Philip Rakity <prakity@marvell.com>
Acked-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
drivers/mmc/host/sdhci.c