Commit | Line | Data |
---|---|---|
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 | |
19f44246 LPC |
24 | - disable-wp: When set no physical WP line is present. This property should |
25 | only be specified when the controller has a dedicated write-protect | |
26 | detection logic. If a GPIO is always used for the write-protect detection | |
27 | logic it is sufficient to not specify wp-gpios property in the absence of a WP | |
28 | line. | |
7f217794 | 29 | - max-frequency: maximum operating clock frequency |
8ed765aa DD |
30 | - no-1-8-v: when present, denotes that 1.8v card voltage is not supported on |
31 | this system, even if the controller claims it is. | |
2fdb6e2d GL |
32 | - cap-sd-highspeed: SD high-speed timing is supported |
33 | - cap-mmc-highspeed: MMC high-speed timing is supported | |
b66bd0e4 UH |
34 | - sd-uhs-sdr12: SD UHS SDR12 speed is supported |
35 | - sd-uhs-sdr25: SD UHS SDR25 speed is supported | |
36 | - sd-uhs-sdr50: SD UHS SDR50 speed is supported | |
37 | - sd-uhs-sdr104: SD UHS SDR104 speed is supported | |
38 | - sd-uhs-ddr50: SD UHS DDR50 speed is supported | |
2fdb6e2d | 39 | - cap-power-off-card: powering off the card is safe |
794f1578 | 40 | - cap-mmc-hw-reset: eMMC hardware reset is supported |
2fdb6e2d | 41 | - cap-sdio-irq: enable SDIO IRQ signalling on this interface |
5a36d6bc | 42 | - full-pwr-cycle: full power cycle of the card is supported |
87a0f46a PG |
43 | - mmc-ddr-1_8v: eMMC high-speed DDR mode(1.8V I/O) is supported |
44 | - mmc-ddr-1_2v: eMMC high-speed DDR mode(1.2V I/O) is supported | |
321bd41d JC |
45 | - mmc-hs200-1_8v: eMMC HS200 mode(1.8V I/O) is supported |
46 | - mmc-hs200-1_2v: eMMC HS200 mode(1.2V I/O) is supported | |
c373eb48 SJ |
47 | - mmc-hs400-1_8v: eMMC HS400 mode(1.8V I/O) is supported |
48 | - mmc-hs400-1_2v: eMMC HS400 mode(1.2V I/O) is supported | |
3d705d14 SH |
49 | - dsr: Value the card's (optional) Driver Stage Register (DSR) should be |
50 | programmed with. Valid range: [0 .. 0xffff]. | |
7f217794 | 51 | |
6da15e96 GL |
52 | *NOTE* on CD and WP polarity. To use common for all SD/MMC host controllers line |
53 | polarity properties, we have to fix the meaning of the "normal" and "inverted" | |
54 | line levels. We choose to follow the SDHCI standard, which specifies both those | |
55 | lines as "active low." Therefore, using the "cd-inverted" property means, that | |
56 | the CD line is active high, i.e. it is high, when a card is inserted. Similar | |
57 | logic applies to the "wp-inverted" property. | |
58 | ||
59 | CD and WP lines can be implemented on the hardware in one of two ways: as GPIOs, | |
60 | specified in cd-gpios and wp-gpios properties, or as dedicated pins. Polarity of | |
61 | dedicated pins can be specified, using *-inverted properties. GPIO polarity can | |
62 | also be specified using the OF_GPIO_ACTIVE_LOW flag. This creates an ambiguity | |
63 | in the latter case. We choose to use the XOR logic for GPIO CD and WP lines. | |
64 | This means, the two properties are "superimposed," for example leaving the | |
65 | OF_GPIO_ACTIVE_LOW flag clear and specifying the respective *-inverted | |
66 | property results in a double-inversion and actually means the "normal" line | |
67 | polarity is in effect. | |
68 | ||
e5d0e9c5 AK |
69 | Optional SDIO properties: |
70 | - keep-power-in-suspend: Preserves card power during a suspend/resume cycle | |
71a0151c SH |
71 | - wakeup-source: Enables wake up of host system on SDIO IRQ assertion |
72 | (Legacy property supported: "enable-sdio-wakeup") | |
e5d0e9c5 | 73 | |
a31edf1e | 74 | |
0e6d6332 UH |
75 | MMC power sequences: |
76 | -------------------- | |
77 | ||
78 | System on chip designs may specify a specific MMC power sequence. To | |
79 | successfully detect an (e)MMC/SD/SDIO card, that power sequence must be | |
80 | maintained while initializing the card. | |
81 | ||
82 | Optional property: | |
83 | - mmc-pwrseq: phandle to the MMC power sequence node. See "mmc-pwrseq-*" | |
84 | for documentation of MMC power sequence bindings. | |
85 | ||
86 | ||
a31edf1e SH |
87 | Use of Function subnodes |
88 | ------------------------ | |
89 | ||
90 | On embedded systems the cards connected to a host may need additional | |
91 | properties. These can be specified in subnodes to the host controller node. | |
92 | The subnodes are identified by the standard 'reg' property. | |
93 | Which information exactly can be specified depends on the bindings for the | |
94 | SDIO function driver for the subnode, as specified by the compatible string. | |
95 | ||
96 | Required host node properties when using function subnodes: | |
97 | - #address-cells: should be one. The cell is the slot id. | |
98 | - #size-cells: should be zero. | |
99 | ||
100 | Required function subnode properties: | |
101 | - compatible: name of SDIO function following generic names recommended practice | |
102 | - reg: Must contain the SDIO function number of the function this subnode | |
103 | describes. A value of 0 denotes the memory SD function, values from | |
104 | 1 to 7 denote the SDIO functions. | |
105 | ||
106 | ||
107 | Examples | |
108 | -------- | |
109 | ||
110 | Basic example: | |
7f217794 AB |
111 | |
112 | sdhci@ab000000 { | |
113 | compatible = "sdhci"; | |
114 | reg = <0xab000000 0x200>; | |
115 | interrupts = <23>; | |
116 | bus-width = <4>; | |
117 | cd-gpios = <&gpio 69 0>; | |
118 | cd-inverted; | |
119 | wp-gpios = <&gpio 70 0>; | |
120 | max-frequency = <50000000>; | |
e5d0e9c5 | 121 | keep-power-in-suspend; |
71a0151c | 122 | wakeup-source; |
0e6d6332 | 123 | mmc-pwrseq = <&sdhci0_pwrseq> |
7f217794 | 124 | } |
a31edf1e SH |
125 | |
126 | Example with sdio function subnode: | |
127 | ||
128 | mmc3: mmc@01c12000 { | |
129 | #address-cells = <1>; | |
130 | #size-cells = <0>; | |
131 | ||
132 | pinctrl-names = "default"; | |
133 | pinctrl-0 = <&mmc3_pins_a>; | |
134 | vmmc-supply = <®_vmmc3>; | |
135 | bus-width = <4>; | |
136 | non-removable; | |
0e6d6332 | 137 | mmc-pwrseq = <&sdhci0_pwrseq> |
a31edf1e SH |
138 | status = "okay"; |
139 | ||
140 | brcmf: bcrmf@1 { | |
141 | reg = <1>; | |
142 | compatible = "brcm,bcm43xx-fmac"; | |
143 | interrupt-parent = <&pio>; | |
144 | interrupts = <10 8>; /* PH10 / EINT10 */ | |
145 | interrupt-names = "host-wake"; | |
146 | }; | |
147 | }; |