mmc: Fix mmc_delay() function

[linux-2.6] / drivers / mmc / mmc.c

diff --git a/drivers/mmc/mmc.c b/drivers/mmc/mmc.c
index 2d5b93000dee545bf9c4dcebfa6b02f21cb67058..82b7643c165489685e8eafe9a17daf8071ce6dc5 100644 (file)
--- a/drivers/mmc/mmc.c
+++ b/drivers/mmc/mmc.c
@@ -397,23 +397,23 @@ static int mmc_select_card(struct mmc_host *host, struct mmc_card *card)
                return err;
 
        /*
-        * Default bus width is 1 bit.
-        */
-       host->ios.bus_width = MMC_BUS_WIDTH_1;
-
-       /*
-        * We can only change the bus width of the selected
-        * card so therefore we have to put the handling
+        * We can only change the bus width of SD cards when
+        * they are selected so we have to put the handling
         * here.
+        *
+        * The card is in 1 bit mode by default so
+        * we only need to change if it supports the
+        * wider version.
         */
-       if (host->caps & MMC_CAP_4_BIT_DATA) {
+       if (mmc_card_sd(card) &&
+               (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
+
                /*
-                * The card is in 1 bit mode by default so
-                * we only need to change if it supports the
-                * wider version.
-                */
-               if (mmc_card_sd(card) &&
-                       (card->scr.bus_widths & SD_SCR_BUS_WIDTH_4)) {
+               * Default bus width is 1 bit.
+               */
+               host->ios.bus_width = MMC_BUS_WIDTH_1;
+
+               if (host->caps & MMC_CAP_4_BIT_DATA) {
                        struct mmc_command cmd;
                        cmd.opcode = SD_APP_SET_BUS_WIDTH;
                        cmd.arg = SD_BUS_WIDTH_4;
@@ -454,11 +454,11 @@ static void mmc_deselect_cards(struct mmc_host *host)
 
 static inline void mmc_delay(unsigned int ms)
 {
-       if (ms < HZ / 1000) {
-               yield();
+       if (ms < 1000 / HZ) {
+               cond_resched();
                mdelay(ms);
        } else {
-               msleep_interruptible (ms);
+               msleep(ms);
        }
 }
 
@@ -1055,6 +1055,29 @@ static void mmc_process_ext_csds(struct mmc_host *host)
                }
 
                mmc_card_set_highspeed(card);
+
+               /* Check for host support for wide-bus modes. */
+               if (!(host->caps & MMC_CAP_4_BIT_DATA)) {
+                       continue;
+               }
+
+               /* Activate 4-bit support. */
+               cmd.opcode = MMC_SWITCH;
+               cmd.arg = (MMC_SWITCH_MODE_WRITE_BYTE << 24) |
+                         (EXT_CSD_BUS_WIDTH << 16) |
+                         (EXT_CSD_BUS_WIDTH_4 << 8) |
+                         EXT_CSD_CMD_SET_NORMAL;
+               cmd.flags = MMC_RSP_R1B | MMC_CMD_AC;
+
+               err = mmc_wait_for_cmd(host, &cmd, CMD_RETRIES);
+               if (err != MMC_ERR_NONE) {
+                       printk("%s: failed to switch card to "
+                              "mmc v4 4-bit bus mode.\n",
+                              mmc_hostname(card->host));
+                       continue;
+               }
+
+               host->ios.bus_width = MMC_BUS_WIDTH_4;
        }
 
        kfree(ext_csd);