Documentation/devicetree/bindings/mmc/sdhci-st.txt

Source file repositories/reference/linux-study-clean/Documentation/devicetree/bindings/mmc/sdhci-st.txt

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Linux kernel
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Documentation/devicetree/bindings/mmc/sdhci-st.txt
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.txt
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111
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Support Tooling And Documentation
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Documentation
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Support Tooling And Documentation: documentation
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atlas-only

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Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

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This file documents the differences between the core properties in
Documentation/devicetree/bindings/mmc/mmc.txt and the properties
used by the sdhci-st driver.

Required properties:
- compatible:		Must be "st,sdhci" and it can be compatible to "st,sdhci-stih407"
			to set the internal glue logic used for configuring the MMC
			subsystem (mmcss) inside the FlashSS (available in STiH407 SoC
			family).

- clock-names:		Should be "mmc" and "icn".  (NB: The latter is not compulsory)
			See: Documentation/devicetree/bindings/resource-names.txt
- clocks:		Phandle to the clock.
			See: Documentation/devicetree/bindings/clock/clock-bindings.txt

- interrupts:		One mmc interrupt should be described here.
- interrupt-names:	Should be "mmcirq".

- pinctrl-names:	A pinctrl state names "default" must be defined.
- pinctrl-0:		Phandle referencing pin configuration of the sd/emmc controller.
			See: Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt

- reg:			This must provide the host controller base address and it can also
			contain the FlashSS Top register for TX/RX delay used by the driver
			to configure DLL inside the flashSS, if so reg-names must also be
			specified.

Optional properties:
- reg-names:		Should be "mmc" and "top-mmc-delay". "top-mmc-delay" is optional
			for eMMC on stih407 family silicon to configure DLL inside FlashSS.

- non-removable:	Non-removable slot. Also used for configuring mmcss in STiH407 SoC
			family.
			See:  Documentation/devicetree/bindings/mmc/mmc.txt.

- bus-width:		Number of data lines.
			See:  Documentation/devicetree/bindings/mmc/mmc.txt.

- max-frequency:	Can be 200MHz, 100MHz or 50MHz (default) and used for
			configuring the CCONFIG3 in the mmcss.
			See:  Documentation/devicetree/bindings/mmc/mmc.txt.

- resets:		Phandle and reset specifier pair to softreset line of HC IP.
			See: Documentation/devicetree/bindings/reset/reset.txt

- vqmmc-supply:		Phandle to the regulator dt node, mentioned as the vcc/vdd
			supply in eMMC/SD specs.

- sd-uhs-sdr50:	To enable the SDR50 in the mmcss.
			See:  Documentation/devicetree/bindings/mmc/mmc.txt.

- sd-uhs-sdr104:	To enable the SDR104 in the mmcss.
			See:  Documentation/devicetree/bindings/mmc/mmc.txt.

- sd-uhs-ddr50:		To enable the DDR50 in the mmcss.
			See:  Documentation/devicetree/bindings/mmc/mmc.txt.

Example:

/* Example stih416e eMMC configuration */

mmc0: sdhci@fe81e000 {
	compatible	= "st,sdhci";
	reg		= <0xfe81e000 0x1000>;
	interrupts	= <GIC_SPI 127 IRQ_TYPE_NONE>;
	interrupt-names	= "mmcirq";
	pinctrl-names	= "default";
	pinctrl-0	= <&pinctrl_mmc0>;
	clock-names	= "mmc";
	clocks		= <&clk_s_a1_ls 1>;

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