Fix wrong sdhci host control register read and write

The patch fixes the improper read and write of sdhci
host control register for sdma transfer.

The problem comes when reading and writing 1 byte long
host control register with the sdhci_readl() and
sdhci_writel(). The misuse of these functions overwrite
the value of the next registers which are in 4 bytes boundary.

This patch replaces four byte register read/write functions
with one byte read/write ones. Beside, it eliminates
unnecessary bit operation. i.e. or-ing zero against a variable.

Signed-off-by: Juhyun (Justin) Oh <Juhyun_Oh@sigmadesigns.com>

diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c
index 14fe41f6c4cc91aa2e300a203eb0f62fe8635100..dfb2eeeb4de8321004afeddf8358ea9909ed62b1 100644 (file)
--- a/drivers/mmc/sdhci.c
+++ b/drivers/mmc/sdhci.c
@@ -68,10 +68,9 @@ static int sdhci_transfer_data(struct sdhci_host *host, struct mmc_data *data,
        unsigned int stat, rdy, mask, timeout, block = 0;
 #ifdef CONFIG_MMC_SDMA
        unsigned char ctrl;
-       ctrl = sdhci_readl(host, SDHCI_HOST_CONTROL);
+       ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
        ctrl &= ~SDHCI_CTRL_DMA_MASK;
-       ctrl |= SDHCI_CTRL_SDMA;
-       sdhci_writel(host, ctrl, SDHCI_HOST_CONTROL);
+       sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 #endif
 
        timeout = 1000000;