mmc: check status after MMC SWITCH command

According to the standard, the SWITCH command should be followed by a
SEND_STATUS command to check for errors.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 42 insertions, 6 deletions

diff --git a/drivers/mmc/core/mmc.c b/drivers/mmc/core/mmc.c
index e0bfa9515c8a..a6b5fe9d3969 100644
--- a/drivers/mmc/core/mmc.c
+++ b/drivers/mmc/core/mmc.c
@@ -416,12 +416,17 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
                 (host->caps & MMC_CAP_MMC_HIGHSPEED)) {
                 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                         EXT_CSD_HS_TIMING, 1);
-                if (err)
+                if (err && err != -EBADMSG)
                         goto free_card;
 
-                mmc_card_set_highspeed(card);
-
-                mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
+                if (err) {
+                        printk(KERN_WARNING "%s: switch to highspeed failed\n",
+                               mmc_hostname(card->host));
+                        err = 0;
+                } else {
+                        mmc_card_set_highspeed(card);
+                        mmc_set_timing(card->host, MMC_TIMING_MMC_HS);
+                }
         }
 
         /*
@@ -456,10 +461,17 @@ static int mmc_init_card(struct mmc_host *host, u32 ocr,
                 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
                                  EXT_CSD_BUS_WIDTH, ext_csd_bit);
 
-                if (err)
+                if (err && err != -EBADMSG)
                         goto free_card;
 
-                mmc_set_bus_width(card->host, bus_width);
+                if (err) {
+                        printk(KERN_WARNING "%s: switch to bus width %d "
+                               "failed\n", mmc_hostname(card->host),
+                               1 << bus_width);
+                        err = 0;
+                } else {
+                        mmc_set_bus_width(card->host, bus_width);
+                }
         }
 
         if (!oldcard)
diff --git a/drivers/mmc/core/mmc_ops.c b/drivers/mmc/core/mmc_ops.c
index 355c6042cf65..d2cb5c634392 100644
--- a/drivers/mmc/core/mmc_ops.c
+++ b/drivers/mmc/core/mmc_ops.c
@@ -390,6 +390,7 @@ int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value)
 {
         int err;
         struct mmc_command cmd;
+        u32 status;
 
         BUG_ON(!card);
         BUG_ON(!card->host);
@@ -407,6 +408,28 @@ int mmc_switch(struct mmc_card *card, u8 set, u8 index, u8 value)
         if (err)
                 return err;
 
+        /* Must check status to be sure of no errors */
+        do {
+                err = mmc_send_status(card, &status);
+                if (err)
+                        return err;
+                if (card->host->caps & MMC_CAP_WAIT_WHILE_BUSY)
+                        break;
+                if (mmc_host_is_spi(card->host))
+                        break;
+        } while (R1_CURRENT_STATE(status) == 7);
+
+        if (mmc_host_is_spi(card->host)) {
+                if (status & R1_SPI_ILLEGAL_COMMAND)
+                        return -EBADMSG;
+        } else {
+                if (status & 0xFDFFA000)
+                        printk(KERN_WARNING "%s: unexpected status %#x after "
+                               "switch", mmc_hostname(card->host), status);
+                if (status & R1_SWITCH_ERROR)
+                        return -EBADMSG;
+        }
+
         return 0;
 }
 
diff --git a/include/linux/mmc/mmc.h b/include/linux/mmc/mmc.h
index b2b40951c16c..c02c8db73701 100644
--- a/include/linux/mmc/mmc.h
+++ b/include/linux/mmc/mmc.h
@@ -128,6 +128,7 @@
 #define R1_STATUS(x)            (x & 0xFFFFE000)
 #define R1_CURRENT_STATE(x)     ((x & 0x00001E00) >> 9) /* sx, b (4 bits) */
 #define R1_READY_FOR_DATA       (1 << 8)        /* sx, a */
+#define R1_SWITCH_ERROR         (1 << 7)        /* sx, c */
 #define R1_APP_CMD              (1 << 5)        /* sr, c */
 
 /*