mmc: fix the condition for MMC version 4

Fix the problem that if we use the chip of MMC version 4 and
the capacity is smaller than 2GB or equal, the mmc->capacity is
invalid. According to the JEDEC Standard, the value of ext_csd's
capacity is valid if the value is more than 2GB.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Acked-by: Andy Fleming <afleming@freescale.com>

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 9a1ee3d..4e4e0fb 100644 (file)
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -853,7 +853,7 @@ int mmc_startup(struct mmc *mmc)
 {
        int err;
        uint mult, freq;
-       u64 cmult, csize;
+       u64 cmult, csize, capacity;
        struct mmc_cmd cmd;
        char ext_csd[512];
        int timeout = 1000;
@@ -1002,9 +1002,16 @@ int mmc_startup(struct mmc *mmc)
                /* check  ext_csd version and capacity */
                err = mmc_send_ext_csd(mmc, ext_csd);
                if (!err & (ext_csd[192] >= 2)) {
-                       mmc->capacity = ext_csd[212] << 0 | ext_csd[213] << 8 |
-                                       ext_csd[214] << 16 | ext_csd[215] << 24;
-                       mmc->capacity *= 512;
+                       /*
+                        * According to the JEDEC Standard, the value of
+                        * ext_csd's capacity is valid if the value is more
+                        * than 2GB
+                        */
+                       capacity = ext_csd[212] << 0 | ext_csd[213] << 8 |
+                                  ext_csd[214] << 16 | ext_csd[215] << 24;
+                       capacity *= 512;
+                       if (capacity > 2 * 1024 * 1024 * 1024)
+                               mmc->capacity = capacity;
                }
 
                /*