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+* 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,dir-output-high: Allow to select direction polarity of external voltage
+ 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,neg-edge: generate data & command on sdmmc clock falling edge
+- st,use-ckin: use sdmmc_ckin pin from an external driver to sample
+ the receive data (example: with voltage switch transceiver).
+
+Example:
+ sdmmc1: mmc@52007000 {
+ 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;
+ };