mmc: sdhci-esdhc-imx: add SDHCI_TRANSFER_MODE read function

Used to read out the correct value of SDHCI_TRANSFER_MODE register
for upper layer.

Signed-off-by: Dong Aisheng <b29396@freescale.com>
Acked-by: Shawn Guo <shawn.guo@linaro.org>

diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index 6c3a5641418774b83a3300f317d30a002e6230ee..886ea975e5df971687090b016878b4abea371518 100644 (file)
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -407,6 +407,22 @@ static u16 esdhc_readw_le(struct sdhci_host *host, int reg)
                return ret;
        }
 
+       if (unlikely(reg == SDHCI_TRANSFER_MODE)) {
+               if (esdhc_is_usdhc(imx_data)) {
+                       u32 m = readl(host->ioaddr + ESDHC_MIX_CTRL);
+                       ret = m & ESDHC_MIX_CTRL_SDHCI_MASK;
+                       /* Swap AC23 bit */
+                       if (m & ESDHC_MIX_CTRL_AC23EN) {
+                               ret &= ~ESDHC_MIX_CTRL_AC23EN;
+                               ret |= SDHCI_TRNS_AUTO_CMD23;
+                       }
+               } else {
+                       ret = readw(host->ioaddr + SDHCI_TRANSFER_MODE);
+               }
+
+               return ret;
+       }
+
        return readw(host->ioaddr + reg);
 }