4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Guenter Roeck <[email protected]>

commit 773dc118756b1f38766063e90e582016be868f09 upstream.

HS400-ES devices fail to initialize with the following error messages.

mmc1: power class selection to bus width 8 ddr 0 failed
mmc1: error -110 whilst initialising MMC card

This was seen on Samsung Chromebook Plus. Code analysis points to
commit 3d4ef329757c ("mmc: core: fix multi-bit bus width without
high-speed mode"), which attempts to set the bus width for all but
HS200 devices unconditionally. However, for HS400-ES, the bus width
is already selected.

Cc: Anssi Hannula <[email protected]>
Cc: Douglas Anderson <[email protected]>
Cc: Brian Norris <[email protected]>
Fixes: 3d4ef329757c ("mmc: core: fix multi-bit bus width ...")
Signed-off-by: Guenter Roeck <[email protected]>
Reviewed-by: Douglas Anderson <[email protected]>
Reviewed-by: Shawn Lin <[email protected]>
Tested-by: Heiko Stuebner <[email protected]>
Signed-off-by: Ulf Hansson <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 drivers/mmc/core/mmc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1690,7 +1690,7 @@ static int mmc_init_card(struct mmc_host
                err = mmc_select_hs400(card);
                if (err)
                        goto free_card;
-       } else {
+       } else if (!mmc_card_hs400es(card)) {
                /* Select the desired bus width optionally */
                err = mmc_select_bus_width(card);
                if (err > 0 && mmc_card_hs(card)) {


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