mmc:fix: Set mmc width according to MMC host capabilities

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@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: Andy Fleming <afleming@gmail.com>

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 596732e..aebe578 100644 (file)
--- 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 (file)
--- 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)