For MMC_BUS_WIDTH_8 case, current code missed setting BM_EIGHTBIT_MODE bit. Also has a small refactor to make the code looks better in readability. So the bit settings witch below logic: SDMMC_BUSMODE register: Set EIGHTBIT_MODE bit for 8 bit mode, Set FOURBIT_MODE bit for 4 bit mode. Clear both EIGHTBIT_MODE and FOURBIT_MODE bits for 1 bit mode. SDMMC_EXTCTRL register: Set EXT_EIGHTBIT bit for 8 bit mode, Clear EXT_EIGHTBIT bit for 1/4 bit mode. Add define for EXT_EIGHTBIT to avoid using magic number. BM_ONEBIT_MASK is no longer used, thus remove it. This patch is untested due to lack of platform with 8-bit hardware. However since the code is there, it's good to make the code match the document. Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx> --- This patch was sent on: http://www.spinics.net/lists/linux-mmc/msg22926.html The document (wm8505 sdmmc controller suppliment.pdf) is available at: https://groups.google.com/group/vt8500-wm8505-linux-kernel/attach/ac3d5037e860a34/wm8505%20sdmmc%20controller%20suppliment.pdf?part=4&authuser=1 Regards, Axel drivers/mmc/host/wmt-sdmmc.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/drivers/mmc/host/wmt-sdmmc.c b/drivers/mmc/host/wmt-sdmmc.c index 8a48a50..6ed18f8 100644 --- a/drivers/mmc/host/wmt-sdmmc.c +++ b/drivers/mmc/host/wmt-sdmmc.c @@ -72,7 +72,6 @@ #define BM_SPI_CS 0x20 #define BM_SD_POWER 0x40 #define BM_SOFT_RESET 0x80 -#define BM_ONEBIT_MASK 0xFD /* SDMMC_BLKLEN bit fields */ #define BLKL_CRCERR_ABORT 0x0800 @@ -120,6 +119,8 @@ #define STS2_DATARSP_BUSY 0x20 #define STS2_DIS_FORCECLK 0x80 +/* SDMMC_EXTCTRL bit fields */ +#define EXT_EIGHTBIT 0x04 /* MMC/SD DMA Controller Registers */ #define SDDMA_GCR 0x100 @@ -672,7 +673,7 @@ static void wmt_mci_request(struct mmc_host *mmc, struct mmc_request *req) static void wmt_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) { struct wmt_mci_priv *priv; - u32 reg_tmp; + u32 busmode, extctrl; priv = mmc_priv(mmc); @@ -687,28 +688,26 @@ static void wmt_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios) if (ios->clock != 0) clk_set_rate(priv->clk_sdmmc, ios->clock); + busmode = readb(priv->sdmmc_base + SDMMC_BUSMODE); + extctrl = readb(priv->sdmmc_base + SDMMC_EXTCTRL); + + busmode &= ~(BM_EIGHTBIT_MODE | BM_FOURBIT_MODE); + extctrl &= ~EXT_EIGHTBIT; + switch (ios->bus_width) { case MMC_BUS_WIDTH_8: - reg_tmp = readb(priv->sdmmc_base + SDMMC_EXTCTRL); - writeb(reg_tmp | 0x04, priv->sdmmc_base + SDMMC_EXTCTRL); + busmode |= BM_EIGHTBIT_MODE; + extctrl |= EXT_EIGHTBIT; break; case MMC_BUS_WIDTH_4: - reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE); - writeb(reg_tmp | BM_FOURBIT_MODE, priv->sdmmc_base + - SDMMC_BUSMODE); - - reg_tmp = readb(priv->sdmmc_base + SDMMC_EXTCTRL); - writeb(reg_tmp & 0xFB, priv->sdmmc_base + SDMMC_EXTCTRL); + busmode |= BM_FOURBIT_MODE; break; case MMC_BUS_WIDTH_1: - reg_tmp = readb(priv->sdmmc_base + SDMMC_BUSMODE); - writeb(reg_tmp & BM_ONEBIT_MASK, priv->sdmmc_base + - SDMMC_BUSMODE); - - reg_tmp = readb(priv->sdmmc_base + SDMMC_EXTCTRL); - writeb(reg_tmp & 0xFB, priv->sdmmc_base + SDMMC_EXTCTRL); break; } + + writeb(busmode, priv->sdmmc_base + SDMMC_BUSMODE); + writeb(extctrl, priv->sdmmc_base + SDMMC_EXTCTRL); } static int wmt_mci_get_ro(struct mmc_host *mmc) -- 1.8.1.2 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html