mmc: Avoid redundant switching to 1-bit bus width for MMC cards

[karo-tx-uboot.git] / drivers / mmc / mmc.c

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 19ac4c482fa5d72504513f651f92aae73ccd88a3..bdd7894231e59113e66154f51549b4aafd4c6b4b 100644 (file)
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -1380,6 +1380,18 @@ static int mmc_startup(struct mmc *mmc)
                        unsigned int extw = ext_csd_bits[idx];
                        unsigned int caps = ext_to_hostcaps[extw];
 
+                       /*
+                        * If the bus width is still not changed,
+                        * don't try to set the default again.
+                        * Otherwise, recover from switch attempts
+                        * by switching to 1-bit bus width.
+                        */
+                       if (extw == EXT_CSD_BUS_WIDTH_1 &&
+                                       mmc->bus_width == 1) {
+                               err = 0;
+                               break;
+                       }
+
                        /*
                         * Check to make sure the card and controller support
                         * these capabilities