[PATCH 3/3] mmc: esdhc i.MX: Support 8bit mode

On Tue, Sep 25, 2012 at 03:15:08PM +0800, Shawn Guo wrote:

On Mon, Sep 24, 2012 at 09:22:25AM +0200, Sascha Hauer wrote:

quoted

The i.MX esdhc has a nonstandard bit layout for the SDHCI_HOST_CONTROL
register. To support 8bit bus width on i.MX populate the platform_bus_width
callback. This is tested on an i.MX25, but should according to the datasheets
work on the other i.MX using this hardware aswell. The i.MX6, while having
a SDHCI_SPEC_300 controller, still uses the same nonstandard register layout.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
---
 .../devicetree/bindings/mmc/fsl-imx-esdhc.txt      |    1 +
 arch/arm/plat-mxc/include/mach/esdhc.h             |    1 +
 drivers/mmc/host/sdhci-esdhc-imx.c                 |   56 ++++++++++++++++++--
 3 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
index 1dd6225..c989994 100644
--- a/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt
+++ b/Documentation/devicetree/bindings/mmc/fsl-imx-esdhc.txt

@@ -12,6 +12,7 @@ Required properties:
 Optional properties:
 - fsl,cd-controller : Indicate to use controller internal card detection
 - fsl,wp-controller : Indicate to use controller internal write protection
+- bus-width : Maximum supported bus width. Defaults to 4 if omitted

This is a common mmc property documented in bindings/mmc/mmc.txt.
Instead of duplicating the documentation, we should try to make our
implementation conform to the common definition of the property.

It is conform to the common definition, so all I have to do is drop the
line duplicating the docs. That's easy ;)

quoted

+		break;
+	case MMC_BUS_WIDTH_4:
+		ctrl = FSL_SDHCI_CTRL_4BITBUS;
+		break;
+	default:
+		ctrl = 0;

... 
		ctrl = FSL_SDHCI_CTRL_1BITBUS;

Any better?

ok.

quoted

 	if (is_imx25_esdhc(imx_data) || is_imx35_esdhc(imx_data))
 		/* Fix errata ENGcm07207 present on i.MX25 and i.MX35 */
 		host->quirks |= SDHCI_QUIRK_NO_MULTIBLOCK
-			| SDHCI_QUIRK_BROKEN_ADMA;
+			 | SDHCI_QUIRK_BROKEN_ADMA;
 

Why this change?

Accident. Will drop.

Sascha


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