1* Synopsys Designware Mobile Storage Host Controller
2
3The Synopsys designware mobile storage host controller is used to interface
4a SoC with storage medium such as eMMC or SD/MMC cards. This file documents
5differences between the core mmc properties described by mmc.txt and the
6properties used by the Synopsys Designware Mobile Storage Host Controller.
7
8Required Properties:
9
10* compatible: should be
11	- snps,dw-mshc: for controllers compliant with synopsys 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 a GPIO is not used
30	  for write-protect, this property is optional.
31
32	* disable-wp: If the wp-gpios property isn't present then (by default)
33	  we'd assume that the write protect is hooked up directly to the
34	  controller's special purpose write protect line (accessible via
35	  the WRTPRT register).  However, it's possible that we simply don't
36	  want write protect.  In that case specify 'disable-wp'.
37	  NOTE: This property is not required for slots known to always
38	  connect to eMMC or SDIO cards.
39
40Optional properties:
41
42* clocks: from common clock binding: handle to biu and ciu clocks for the
43  bus interface unit clock and the card interface unit clock.
44
45* clock-names: from common clock binding: Shall be "biu" and "ciu".
46  If the biu clock is missing we'll simply skip enabling it.  If the
47  ciu clock is missing we'll just assume that the clock is running at
48  clock-frequency.  It is an error to omit both the ciu clock and the
49  clock-frequency.
50
51* clock-frequency: should be the frequency (in Hz) of the ciu clock.  If this
52  is specified and the ciu clock is specified then we'll try to set the ciu
53  clock to this at probe time.
54
55* clock-freq-min-max: Minimum and Maximum clock frequency for card output
56  clock(cclk_out). If it's not specified, max is 200MHZ and min is 400KHz by default.
57
58* num-slots: specifies the number of slots supported by the controller.
59  The number of physical slots actually used could be equal or less than the
60  value specified by num-slots. If this property is not specified, the value
61  of num-slot property is assumed to be 1.
62
63* fifo-depth: The maximum size of the tx/rx fifo's. If this property is not
64  specified, the default value of the fifo size is determined from the
65  controller registers.
66
67* card-detect-delay: Delay in milli-seconds before detecting card after card
68  insert event. The default value is 0.
69
70* supports-highspeed (DEPRECATED): Enables support for high speed cards (up to 50MHz)
71			   (use "cap-mmc-highspeed" or "cap-sd-highspeed" instead)
72
73* broken-cd: as documented in mmc core bindings.
74
75* vmmc-supply: The phandle to the regulator to use for vmmc.  If this is
76  specified we'll defer probe until we can find this regulator.
77
78Aliases:
79
80- All the MSHC controller nodes should be represented in the aliases node using
81  the following format 'mshc{n}' where n is a unique number for the alias.
82
83Example:
84
85The MSHC controller node can be split into two portions, SoC specific and
86board specific portions as listed below.
87
88	dwmmc0@12200000 {
89		compatible = "snps,dw-mshc";
90		clocks = <&clock 351>, <&clock 132>;
91		clock-names = "biu", "ciu";
92		reg = <0x12200000 0x1000>;
93		interrupts = <0 75 0>;
94		#address-cells = <1>;
95		#size-cells = <0>;
96	};
97
98	dwmmc0@12200000 {
99		clock-frequency = <400000000>;
100		clock-freq-min-max = <400000 200000000>;
101		num-slots = <1>;
102		broken-cd;
103		fifo-depth = <0x80>;
104		card-detect-delay = <200>;
105		vmmc-supply = <&buck8>;
106		bus-width = <8>;
107		cap-mmc-highspeed;
108		cap-sd-highspeed;
109	};
110