[PATCH 1/5] dt-bindings: mmc: document the stm32 sdmmc bindings
Rob Herring
robh at kernel.org
Mon Feb 19 06:47:35 PST 2018
On Thu, Feb 15, 2018 at 02:34:53PM +0100, Ludovic Barre wrote:
> From: Ludovic Barre <ludovic.barre at st.com>
>
> Document the binding for stm32 sdmmc controller.
>
> Signed-off-by: Ludovic Barre <ludovic.barre at st.com>
> ---
> .../devicetree/bindings/mmc/st,stm32-sdmmc.txt | 35 ++++++++++++++++++++++
> 1 file changed, 35 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mmc/st,stm32-sdmmc.txt
>
> diff --git a/Documentation/devicetree/bindings/mmc/st,stm32-sdmmc.txt b/Documentation/devicetree/bindings/mmc/st,stm32-sdmmc.txt
> new file mode 100644
> index 0000000..52eb1f8
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mmc/st,stm32-sdmmc.txt
> @@ -0,0 +1,35 @@
> +* STMicroelectronics STM32 SDMMC controller
> +
> +The highspeed MMC host controller on STM32 soc family
> +provides an interface for MMC, SD and SDIO types of memory cards.
> +
> +This file documents differences between the core properties described
> +by mmc.txt and the properties used by the sdmmc driver.
> +
> +Required properties:
> + - compatible: Should be "st,stm32h7-sdmmc"
> + - reg: mmc controller base registers
> + - interrupts: Should contain the interrupt number
> + - clocks: Should contain phandle for the clock feeding the controller
> + - resets: Should contain phandle for the reset feeding the controller
> +
> +Optional property:
> +- st,dirpol: Allow to select direction polarity of external voltage
This doesn't need to be so terse. Perhaps "st,dir-output-high".
> + transceiver (which manage data and command direction).
> + if set: Voltage transceiver IOs are driven as output when direction signals are high,
> + else: Voltage transceiver IOs are driven as output when direction signals are low.
> +- st,negedge: generate data & command on sdmmc clock falling edge
st,neg-edge
> +- st,pin-ckin: use sdmmc_ckin pin from an external driver to sample
> + the receive data (example: with voltage switch transceiver).
st,use-ckin
> +
> +Example:
> + sdmmc1: sdmmc at 52007000 {
mmc at ...
> + compatible = "st,stm32h7-sdmmc";
> + reg = <0x52007000 0x1000>;
> + interrupts = <49>;
> + clocks = <&rcc SDMMC1_CK>;
> + resets = <&rcc SDMMC1_R>;
> + bus-width = <4>;
> + cap-sd-highspeed;
> + cap-mmc-highspeed;
> + };
> --
> 2.7.4
>
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