xref: /freebsd/sys/contrib/device-tree/Bindings/mmc/mmc-pwrseq-simple.txt (revision 2e3507c25e42292b45a5482e116d278f5515d04d)
1* The simple MMC power sequence provider
2
3The purpose of the simple MMC power sequence provider is to supports a set of
4common properties between various SOC designs. It thus enables us to use the
5same provider for several SOC designs.
6
7Required properties:
8- compatible : contains "mmc-pwrseq-simple".
9
10Optional properties:
11- reset-gpios : contains a list of GPIO specifiers. The reset GPIOs are asserted
12	at initialization and prior we start the power up procedure of the card.
13	They will be de-asserted right after the power has been provided to the
14	card.
15- clocks : Must contain an entry for the entry in clock-names.
16  See ../clocks/clock-bindings.txt for details.
17- clock-names : Must include the following entry:
18  "ext_clock" (External clock provided to the card).
19- post-power-on-delay-ms : Delay in ms after powering the card and
20	de-asserting the reset-gpios (if any)
21- power-off-delay-us : Delay in us after asserting the reset-gpios (if any)
22	during power off of the card.
23
24Example:
25
26	sdhci0_pwrseq {
27		compatible = "mmc-pwrseq-simple";
28		reset-gpios = <&gpio1 12 GPIO_ACTIVE_LOW>;
29		clocks = <&clk_32768_ck>;
30		clock-names = "ext_clock";
31	}
32