From 5fe23c7f51def59f66bc6aeee988ef1a467a2c8c Mon Sep 17 00:00:00 2001 From: Anton Vorontsov <avorontsov@ru.mvista.com> Date: Thu, 18 Jun 2009 00:14:08 +0400 Subject: sdhci: Add support for hosts that are only capable of 1-bit transfers Some hosts (hardware configurations, or particular SD/MMC slots) may not support 4-bit bus. For example, on MPC8569E-MDS boards we can switch between serial (1-bit only) and nibble (4-bit) modes, thought we have to disable more peripherals to work in 4-bit mode. Along with some small core changes, this patch modifies sdhci-of driver, so that now it looks for "sdhci,1-bit-only" property in the device-tree, and if specified we enable a proper quirk. Signed-off-by: Anton Vorontsov <avorontsov@ru.mvista.com> Acked-by: Grant Likely <grant.likely@secretlab.ca> Signed-off-by: Pierre Ossman <pierre@ossman.eu> --- Documentation/powerpc/dts-bindings/fsl/esdhc.txt | 2 ++ 1 file changed, 2 insertions(+) (limited to 'Documentation/powerpc/dts-bindings') diff --git a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt index 5093ddf..3ed3797 100644 --- a/Documentation/powerpc/dts-bindings/fsl/esdhc.txt +++ b/Documentation/powerpc/dts-bindings/fsl/esdhc.txt @@ -10,6 +10,8 @@ Required properties: - interrupts : should contain eSDHC interrupt. - interrupt-parent : interrupt source phandle. - clock-frequency : specifies eSDHC base clock frequency. + - sdhci,1-bit-only : (optional) specifies that a controller can + only handle 1-bit data transfers. Example: -- cgit v1.1