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* Synopsis Designware Mobile Storage Host Controller
The Synopsis designware mobile storage host controller is used to interface
a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
differences between the core mmc properties described by mmc.txt and the
properties used by the Synopsis Designware Mobile Storage Host Controller.
Required Properties:
* compatible: should be
- snps,dw-mshc: for controllers compliant with synopsis dw-mshc.
* #address-cells: should be 1.
* #size-cells: should be 0.
# Slots: The slot specific information are contained within child-nodes with
each child-node representing a supported slot. There should be atleast one
child node representing a card slot. The name of the child node representing
the slot is recommended to be slot@n where n is the unique number of the slot
connnected to the controller. The following are optional properties which
can be included in the slot child node.
* reg: specifies the physical slot number. The valid values of this
property is 0 to (num-slots -1), where num-slots is the value
specified by the num-slots property.
* bus-width: as documented in mmc core bindings.
* wp-gpios: specifies the write protect gpio line. The format of the
gpio specifier depends on the gpio controller. If the write-protect
line is not available, this property is optional.
Optional properties:
* num-slots: specifies the number of slots supported by the controller.
The number of physical slots actually used could be equal or less than the
value specified by num-slots. If this property is not specified, the value
of num-slot property is assumed to be 1.
* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
specified, the default value of the fifo size is determined from the
controller registers.
* card-detect-delay: Delay in milli-seconds before detecting card after card
insert event. The default value is 0.
* supports-highspeed: Enables support for high speed cards (upto 50MHz)
* broken-cd: as documented in mmc core bindings.
Aliases:
- All the MSHC controller nodes should be represented in the aliases node using
the following format 'mshc{n}' where n is a unique number for the alias.
Example:
The MSHC controller node can be split into two portions, SoC specific and
board specific portions as listed below.
dwmmc0@12200000 {
compatible = "snps,dw-mshc";
reg = <0x12200000 0x1000>;
interrupts = <0 75 0>;
#address-cells = <1>;
#size-cells = <0>;
};
dwmmc0@12200000 {
num-slots = <1>;
supports-highspeed;
broken-cd;
fifo-depth = <0x80>;
card-detect-delay = <200>;
slot@0 {
reg = <0>;
bus-width = <8>;
};
};
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