From 2c011847c129491084a19c753a039a3441b7dce4 Mon Sep 17 00:00:00 2001 From: "Juhyun \\(Justin\\) Oh" Date: Fri, 13 Sep 2013 18:06:00 +0000 Subject: [PATCH] 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 --- drivers/mmc/sdhci.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/mmc/sdhci.c b/drivers/mmc/sdhci.c index 14fe41f..dfb2eee 100644 --- 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;