Commit | Line | Data |
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7f217794 AB |
1 | These properties are common to multiple MMC host controllers. Any host |
2 | that requires the respective functionality should implement them using | |
3 | these definitions. | |
4 | ||
ed3efc1c CB |
5 | Interpreted by the OF core: |
6 | - reg: Registers location and length. | |
7 | - interrupts: Interrupts used by the MMC controller. | |
8 | ||
abe1e05d | 9 | Card detection: |
b477426e | 10 | If no property below is supplied, host native card detect is used. |
abe1e05d CB |
11 | Only one of the properties in this section should be supplied: |
12 | - broken-cd: There is no card detection available; polling must be used. | |
13 | - cd-gpios: Specify GPIOs for card detection, see gpio binding | |
14 | - non-removable: non-removable slot (like eMMC); assume always present. | |
15 | ||
7f217794 | 16 | Optional properties: |
28c2a62b SG |
17 | - bus-width: Number of data lines, can be <1>, <4>, or <8>. The default |
18 | will be <1> if the property is absent. | |
ed3efc1c | 19 | - wp-gpios: Specify GPIOs for write protection, see gpio binding |
6da15e96 GL |
20 | - cd-inverted: when present, polarity on the CD line is inverted. See the note |
21 | below for the case, when a GPIO is used for the CD line | |
22 | - wp-inverted: when present, polarity on the WP line is inverted. See the note | |
23 | below for the case, when a GPIO is used for the WP line | |
7f217794 | 24 | - max-frequency: maximum operating clock frequency |
8ed765aa DD |
25 | - no-1-8-v: when present, denotes that 1.8v card voltage is not supported on |
26 | this system, even if the controller claims it is. | |
2fdb6e2d GL |
27 | - cap-sd-highspeed: SD high-speed timing is supported |
28 | - cap-mmc-highspeed: MMC high-speed timing is supported | |
b66bd0e4 UH |
29 | - sd-uhs-sdr12: SD UHS SDR12 speed is supported |
30 | - sd-uhs-sdr25: SD UHS SDR25 speed is supported | |
31 | - sd-uhs-sdr50: SD UHS SDR50 speed is supported | |
32 | - sd-uhs-sdr104: SD UHS SDR104 speed is supported | |
33 | - sd-uhs-ddr50: SD UHS DDR50 speed is supported | |
2fdb6e2d GL |
34 | - cap-power-off-card: powering off the card is safe |
35 | - cap-sdio-irq: enable SDIO IRQ signalling on this interface | |
5a36d6bc | 36 | - full-pwr-cycle: full power cycle of the card is supported |
87a0f46a PG |
37 | - mmc-ddr-1_8v: eMMC high-speed DDR mode(1.8V I/O) is supported |
38 | - mmc-ddr-1_2v: eMMC high-speed DDR mode(1.2V I/O) is supported | |
321bd41d JC |
39 | - mmc-hs200-1_8v: eMMC HS200 mode(1.8V I/O) is supported |
40 | - mmc-hs200-1_2v: eMMC HS200 mode(1.2V I/O) is supported | |
c373eb48 SJ |
41 | - mmc-hs400-1_8v: eMMC HS400 mode(1.8V I/O) is supported |
42 | - mmc-hs400-1_2v: eMMC HS400 mode(1.2V I/O) is supported | |
3d705d14 SH |
43 | - dsr: Value the card's (optional) Driver Stage Register (DSR) should be |
44 | programmed with. Valid range: [0 .. 0xffff]. | |
7f217794 | 45 | |
6da15e96 GL |
46 | *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line |
47 | polarity properties, we have to fix the meaning of the "normal" and "inverted" | |
48 | line levels. We choose to follow the SDHCI standard, which specifies both those | |
49 | lines as "active low." Therefore, using the "cd-inverted" property means, that | |
50 | the CD line is active high, i.e. it is high, when a card is inserted. Similar | |
51 | logic applies to the "wp-inverted" property. | |
52 | ||
53 | CD and WP lines can be implemented on the hardware in one of two ways: as GPIOs, | |
54 | specified in cd-gpios and wp-gpios properties, or as dedicated pins. Polarity of | |
55 | dedicated pins can be specified, using *-inverted properties. GPIO polarity can | |
56 | also be specified using the OF_GPIO_ACTIVE_LOW flag. This creates an ambiguity | |
57 | in the latter case. We choose to use the XOR logic for GPIO CD and WP lines. | |
58 | This means, the two properties are "superimposed," for example leaving the | |
59 | OF_GPIO_ACTIVE_LOW flag clear and specifying the respective *-inverted | |
60 | property results in a double-inversion and actually means the "normal" line | |
61 | polarity is in effect. | |
62 | ||
e5d0e9c5 AK |
63 | Optional SDIO properties: |
64 | - keep-power-in-suspend: Preserves card power during a suspend/resume cycle | |
65 | - enable-sdio-wakeup: Enables wake up of host system on SDIO IRQ assertion | |
66 | ||
a31edf1e SH |
67 | |
68 | Use of Function subnodes | |
69 | ------------------------ | |
70 | ||
71 | On embedded systems the cards connected to a host may need additional | |
72 | properties. These can be specified in subnodes to the host controller node. | |
73 | The subnodes are identified by the standard 'reg' property. | |
74 | Which information exactly can be specified depends on the bindings for the | |
75 | SDIO function driver for the subnode, as specified by the compatible string. | |
76 | ||
77 | Required host node properties when using function subnodes: | |
78 | - #address-cells: should be one. The cell is the slot id. | |
79 | - #size-cells: should be zero. | |
80 | ||
81 | Required function subnode properties: | |
82 | - compatible: name of SDIO function following generic names recommended practice | |
83 | - reg: Must contain the SDIO function number of the function this subnode | |
84 | describes. A value of 0 denotes the memory SD function, values from | |
85 | 1 to 7 denote the SDIO functions. | |
86 | ||
87 | ||
88 | Examples | |
89 | -------- | |
90 | ||
91 | Basic example: | |
7f217794 AB |
92 | |
93 | sdhci@ab000000 { | |
94 | compatible = "sdhci"; | |
95 | reg = <0xab000000 0x200>; | |
96 | interrupts = <23>; | |
97 | bus-width = <4>; | |
98 | cd-gpios = <&gpio 69 0>; | |
99 | cd-inverted; | |
100 | wp-gpios = <&gpio 70 0>; | |
101 | max-frequency = <50000000>; | |
e5d0e9c5 AK |
102 | keep-power-in-suspend; |
103 | enable-sdio-wakeup; | |
7f217794 | 104 | } |
a31edf1e SH |
105 | |
106 | Example with sdio function subnode: | |
107 | ||
108 | mmc3: mmc@01c12000 { | |
109 | #address-cells = <1>; | |
110 | #size-cells = <0>; | |
111 | ||
112 | pinctrl-names = "default"; | |
113 | pinctrl-0 = <&mmc3_pins_a>; | |
114 | vmmc-supply = <®_vmmc3>; | |
115 | bus-width = <4>; | |
116 | non-removable; | |
117 | status = "okay"; | |
118 | ||
119 | brcmf: bcrmf@1 { | |
120 | reg = <1>; | |
121 | compatible = "brcm,bcm43xx-fmac"; | |
122 | interrupt-parent = <&pio>; | |
123 | interrupts = <10 8>; /* PH10 / EINT10 */ | |
124 | interrupt-names = "host-wake"; | |
125 | }; | |
126 | }; |