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Subject[PATCH] mmc: mmc: Fix the timing for clock changing in mmc
The clock has to be changed after sending CMD6 for HS mode selection in
mmc_hs400_to_hs200() function.

The JEDEC 5.0 and 5.1 said that "High-speed" mode selection has to
enable the the high speed mode timing in the Device, before chaning the
clock frequency to a frequency between 26MHz and 52MHz.

Signed-off-by: Kyungmin Seo <kyungmin.seo@intel.com>
---
drivers/mmc/core/mmc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index 3486bc7fbb64..98640b51c73e 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -1196,10 +1196,6 @@ int mmc_hs400_to_hs200(struct mmc_card *card)
int err;
u8 val;

- /* Reduce frequency to HS */
- max_dtr = card->ext_csd.hs_max_dtr;
- mmc_set_clock(host, max_dtr);
-
/* Switch HS400 to HS DDR */
val = EXT_CSD_TIMING_HS;
err = __mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_HS_TIMING,
@@ -1210,6 +1206,10 @@ int mmc_hs400_to_hs200(struct mmc_card *card)

mmc_set_timing(host, MMC_TIMING_MMC_DDR52);

+ /* Reduce frequency to HS */
+ max_dtr = card->ext_csd.hs_max_dtr;
+ mmc_set_clock(host, max_dtr);
+
err = mmc_switch_status(card);
if (err)
goto out_err;
--
2.17.1
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