mmc: Fixes for Dual Data Rate (DDR) support

The DDR support patch needs the following fixes:

- The block driver does not need to know about DDR, any more
  than it needs to know about bus width.
- Not only the card must be switched to DDR mode.  The host
  controller must also be configured, which is done through
  the 'set_ios()' function.
- Do not set the DDR mode state until after the switch command
  is successful.
- Setting block length is not supported in DDR mode.  Make that
  a core function and change the other place it is used (mmc_test)
  also.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 26 insertions, 2 deletions

diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 46029d5c036..7cb352b3b24 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -651,14 +651,23 @@ void mmc_set_bus_mode(struct mmc_host *host, unsigned int mode)
 }
 
 /*
- * Change data bus width of a host.
+ * Change data bus width and DDR mode of a host.
  */
-void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
+void mmc_set_bus_width_ddr(struct mmc_host *host, unsigned int width, int ddr)
 {
         host->ios.bus_width = width;
+        host->ios.ddr = ddr ? MMC_DDR_MODE : MMC_SDR_MODE;
         mmc_set_ios(host);
 }
 
+/*
+ * Change data bus width of a host.
+ */
+void mmc_set_bus_width(struct mmc_host *host, unsigned int width)
+{
+        mmc_set_bus_width_ddr(host, width, 0);
+}
+
 /**
  * mmc_vdd_to_ocrbitnum - Convert a voltage to the OCR bit number
  * @vdd:        voltage (mV)
@@ -1399,6 +1408,21 @@ int mmc_erase_group_aligned(struct mmc_card *card, unsigned int from,
 }
 EXPORT_SYMBOL(mmc_erase_group_aligned);
 
+int mmc_set_blocklen(struct mmc_card *card, unsigned int blocklen)
+{
+        struct mmc_command cmd;
+
+        if (mmc_card_blockaddr(card) || mmc_card_ddr_mode(card))
+                return 0;
+
+        memset(&cmd, 0, sizeof(struct mmc_command));
+        cmd.opcode = MMC_SET_BLOCKLEN;
+        cmd.arg = blocklen;
+        cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
+        return mmc_wait_for_cmd(card->host, &cmd, 5);
+}
+EXPORT_SYMBOL(mmc_set_blocklen);
+
 void mmc_rescan(struct work_struct *work)
 {
         struct mmc_host *host =