[PATCH] mmc: Change the frequency to MMC_HS_52 when selecting hs400

[Venkatesh Yadav Abbarapu]

Per JESD84-B51 P47, host need to change frequency to <=52MHz
after setting HS_TIMING to 0x1, and host need to set the
8-bit DDR buswidth. Currently setting the frequency to 26MHz
and trying to switch 8-bit DDR buswidth resulting timeouts.

mmc dev 1 0
Select HS400 failed -110
switch to partitions #0, OK
mmc1(part 0) is current device

Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu at amd.com>
---
 drivers/mmc/mmc.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 7b068c71ff..a2ed99aefe 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -962,8 +962,8 @@ static int mmc_set_card_speed(struct mmc *mmc, enum bus_mode mode,
 	 * Extended CSD. Reconfigure the controller to run at HS mode.
 	 */
 	if (hsdowngrade) {
-		mmc_select_mode(mmc, MMC_HS);
-		mmc_set_clock(mmc, mmc_mode2freq(mmc, MMC_HS), false);
+		mmc_select_mode(mmc, MMC_HS_52);
+		mmc_set_clock(mmc, mmc_mode2freq(mmc, MMC_HS_52), false);
 	}
 #endif
 
@@ -2043,7 +2043,7 @@ static int mmc_select_hs400(struct mmc *mmc)
 	}
 
 	/* Set back to HS */
-	mmc_set_card_speed(mmc, MMC_HS, true);
+	mmc_set_card_speed(mmc, MMC_HS_52, true);
 
 	err = mmc_hs400_prepare_ddr(mmc);
 	if (err)
-- 
2.17.1