[linux-2.6-block.git] / Documentation / devicetree / bindings / mmc / synposis-dw-mshc.txt

* 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>;
		};
	};
Commit	Line	Data
c91eab4b TA	1	* Synopsis Designware Mobile Storage Host Controller
	2
	3	The Synopsis designware mobile storage host controller is used to interface
	4	a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
	5	differences between the core mmc properties described by mmc.txt and the
	6	properties used by the Synopsis Designware Mobile Storage Host Controller.
	7
	8	Required Properties:
	9
	10	* compatible: should be
	11	- snps,dw-mshc: for controllers compliant with synopsis dw-mshc.
	12	* #address-cells: should be 1.
	13	* #size-cells: should be 0.
	14
	15	# Slots: The slot specific information are contained within child-nodes with
	16	each child-node representing a supported slot. There should be atleast one
	17	child node representing a card slot. The name of the child node representing
	18	the slot is recommended to be slot@n where n is the unique number of the slot
	19	connnected to the controller. The following are optional properties which
	20	can be included in the slot child node.
	21
	22	* reg: specifies the physical slot number. The valid values of this
	23	property is 0 to (num-slots -1), where num-slots is the value
	24	specified by the num-slots property.
	25
	26	* bus-width: as documented in mmc core bindings.
	27
	28	* wp-gpios: specifies the write protect gpio line. The format of the
	29	gpio specifier depends on the gpio controller. If the write-protect
	30	line is not available, this property is optional.
	31
	32	Optional properties:
	33
	34	* num-slots: specifies the number of slots supported by the controller.
	35	The number of physical slots actually used could be equal or less than the
	36	value specified by num-slots. If this property is not specified, the value
	37	of num-slot property is assumed to be 1.
	38
	39	* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
	40	specified, the default value of the fifo size is determined from the
	41	controller registers.
	42
	43	* card-detect-delay: Delay in milli-seconds before detecting card after card
	44	insert event. The default value is 0.
	45
	46	* supports-highspeed: Enables support for high speed cards (upto 50MHz)
	47
	48	* broken-cd: as documented in mmc core bindings.
	49
	50	Aliases:
	51
	52	- All the MSHC controller nodes should be represented in the aliases node using
	53	the following format 'mshc{n}' where n is a unique number for the alias.
	54
	55	Example:
	56
	57	The MSHC controller node can be split into two portions, SoC specific and
	58	board specific portions as listed below.
	59
	60	dwmmc0@12200000 {
	61	compatible = "snps,dw-mshc";
	62	reg = <0x12200000 0x1000>;
	63	interrupts = <0 75 0>;
	64	#address-cells = <1>;
65	#size-cells = <0>;
66	};
67
68	dwmmc0@12200000 {
69	num-slots = <1>;
70	supports-highspeed;
71	broken-cd;
72	fifo-depth = <0x80>;
73	card-detect-delay = <200>;
74
75	slot@0 {
76	reg = <0>;
77	bus-width = <8>;
78	};
79	};