1STM32 Real Time Clock
2
3Required properties:
4- compatible: can be one of the following:
5  - "st,stm32-rtc" for devices compatible with stm32(f4/f7).
6  - "st,stm32h7-rtc" for devices compatible with stm32h7.
7  - "st,stm32mp1-rtc" for devices compatible with stm32mp1.
8- reg: address range of rtc register set.
9- clocks: can use up to two clocks, depending on part used:
10  - "rtc_ck": RTC clock source.
11  - "pclk": RTC APB interface clock.
12    It is not present on stm32(f4/f7).
13    It is required on stm32(h7/mp1).
14- clock-names: must be "rtc_ck" and "pclk".
15    It is required on stm32(h7/mp1).
16- interrupts: rtc alarm interrupt. On stm32mp1, a second interrupt is required
17  for rtc alarm wakeup interrupt.
18- st,syscfg: phandle/offset/mask triplet. The phandle to pwrcfg used to
19  access control register at offset, and change the dbp (Disable Backup
20  Protection) bit represented by the mask, mandatory to disable/enable backup
21  domain (RTC registers) write protection.
22    It is required on stm32(f4/f7/h7).
23
24Optional properties (to override default rtc_ck parent clock on stm32(f4/f7/h7):
25- assigned-clocks: reference to the rtc_ck clock entry.
26- assigned-clock-parents: phandle of the new parent clock of rtc_ck.
27
28Example:
29
30	rtc: rtc@40002800 {
31		compatible = "st,stm32-rtc";
32		reg = <0x40002800 0x400>;
33		clocks = <&rcc 1 CLK_RTC>;
34		assigned-clocks = <&rcc 1 CLK_RTC>;
35		assigned-clock-parents = <&rcc 1 CLK_LSE>;
36		interrupt-parent = <&exti>;
37		interrupts = <17 1>;
38		st,syscfg = <&pwrcfg 0x00 0x100>;
39	};
40
41	rtc: rtc@58004000 {
42		compatible = "st,stm32h7-rtc";
43		reg = <0x58004000 0x400>;
44		clocks = <&rcc RTCAPB_CK>, <&rcc RTC_CK>;
45		clock-names = "pclk", "rtc_ck";
46		assigned-clocks = <&rcc RTC_CK>;
47		assigned-clock-parents = <&rcc LSE_CK>;
48		interrupt-parent = <&exti>;
49		interrupts = <17 1>;
50		interrupt-names = "alarm";
51		st,syscfg = <&pwrcfg 0x00 0x100>;
52	};
53
54	rtc: rtc@5c004000 {
55		compatible = "st,stm32mp1-rtc";
56		reg = <0x5c004000 0x400>;
57		clocks = <&rcc RTCAPB>, <&rcc RTC>;
58		clock-names = "pclk", "rtc_ck";
59		interrupts-extended = <&intc GIC_SPI 3 IRQ_TYPE_NONE>,
60				      <&exti 19 1>;
61	};
62