Re: [PATCH RFT] mmc: wmt-sdmmc: Fix setting BM_EIGHTBIT_MODE bit in wmt_mci_set_ios()

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On 22/10/13 21:54, Axel Lin wrote:
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.

Signed-off-by: Axel Lin <axel.lin@xxxxxxxxxx>
---
Hi Tony,
After checking wm8505+sdmmc+controller+suppliment.pdf, I'm wondering if this
dirver works for MMC_BUS_WIDTH_8 case without setting BM_EIGHTBIT_MODE bit.
I don't have this h/w to test.
I'd appreciate if you can review and test if this patch works.
Thanks,
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)
I don't have any means of testing this - All the vendor hardware I have uses 4-bit mode.

Regards
Tony Prisk
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