About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog

Documentation / devicetree / bindings / mmc / synposis-dw-mshc.txt


Based on kernel version 3.7. Page generated on 2012-12-12 10:00 EST.

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		};
Hide Line Numbers


About Kernel Documentation Linux Kernel Contact Linux Resources Linux Blog