[U-Boot] [RESEND 1/2] mmc:fix: Set mmc width according to MMC host capabilities

Lukasz Majewski l.majewski at samsung.com
Thu Apr 19 14:39:17 CEST 2012


This patch sets the MMC width according to the MMC host capabilities.
It turned out, that there are some targets (e.g. GONI), which are able
to read data from SPI only at 4 bit mode.
This patch restricts the width number according to the MMC host.

Signed-off-by: Lukasz Majewski <l.majewski at samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park at samsung.com>
Cc: Andy Fleming <afleming at gmail.com>
---
 drivers/mmc/mmc.c |    4 +++-
 include/mmc.h     |    3 +++
 2 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index e70fa9f..618960e 100644
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1199,7 +1199,9 @@ int mmc_startup(struct mmc *mmc)
 		else
 			mmc_set_clock(mmc, 25000000);
 	} else {
-		for (width = EXT_CSD_BUS_WIDTH_8; width >= 0; width--) {
+		width = ((mmc->host_caps & MMC_MODE_MASK_WIDTH_BITS) >>
+			 MMC_MODE_WIDTH_BITS_SHIFT);
+		for (; width >= 0; width--) {
 			/* Set the card to use 4 bit*/
 			err = mmc_switch(mmc, EXT_CSD_CMD_SET_NORMAL,
 					EXT_CSD_BUS_WIDTH, width);
diff --git a/include/mmc.h b/include/mmc.h
index f52df70..ee16349 100644
--- a/include/mmc.h
+++ b/include/mmc.h
@@ -47,6 +47,9 @@
 #define MMC_MODE_SPI		0x400
 #define MMC_MODE_HC		0x800
 
+#define MMC_MODE_MASK_WIDTH_BITS (MMC_MODE_4BIT | MMC_MODE_8BIT)
+#define MMC_MODE_WIDTH_BITS_SHIFT 8
+
 #define SD_DATA_4BIT	0x00040000
 
 #define IS_SD(x) (x->version & SD_VERSION_SD)
-- 
1.7.2.3



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