[PATCH 2/6] dt-bindings: rtc: stm32: add alarm A out property to select output

[Valentin Caron <valentin.caron@foss.st.com>]

STM32 RTC can pulse some SOC pins when an alarm of RTC expires.

This patch adds property to activate alarm A output. The pulse can
output on three pins RTC_OUT1, RTC_OUT2, RTC_OUT2_RMP
(PC13, PB2, PI8 on stm32mp15) (PC13, PB2, PI1 on stm32mp13).

Signed-off-by: Valentin Caron <valentin.caron@foss.st.com>
---
 .../devicetree/bindings/rtc/st,stm32-rtc.yaml | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
index 56d46ea35c5d..71e02604e8de 100644
--- a/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
+++ b/Documentation/devicetree/bindings/rtc/st,stm32-rtc.yaml
@@ -59,6 +59,13 @@ properties:
       Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
       Pinctrl state named "default" may be defined to reserve pin for RTC output.
 
+  st,alarm:
+    $ref: "/schemas/types.yaml#/definitions/uint32"
+    description: |
+      To select and enable RTC Alarm A output.
+      Refer to <include/dt-bindings/rtc/rtc-stm32.h> for the supported values.
+      Pinctrl state named "default" may be defined to reserve pin for RTC output.
+
 allOf:
   - if:
       properties:
@@ -75,6 +82,9 @@ allOf:
         st,lsco:
           maxItems: 0
 
+        st,alarm:
+          maxItems: 0
+
         clock-names: false
 
       required:
@@ -95,6 +105,9 @@ allOf:
         st,lsco:
           maxItems: 0
 
+        st,alarm:
+          maxItems: 0
+
       required:
         - clock-names
         - st,syscfg
@@ -117,6 +130,9 @@ allOf:
         st,lsco:
           maxItems: 1
 
+        st,alarm:
+          maxItems: 1
+
       required:
         - clock-names
 
@@ -153,8 +169,9 @@ examples:
       clocks = <&rcc RTCAPB>, <&rcc RTC>;
       clock-names = "pclk", "rtc_ck";
       interrupts = <GIC_SPI 3 IRQ_TYPE_LEVEL_HIGH>;
+      st,alarm = <RTC_OUT1>;
       st,lsco = <RTC_OUT2_RMP>;
-      pinctrl-0 = <&rtc_out2_rmp_pins_a>;
+      pinctrl-0 = <&rtc_out1_pins_a &rtc_out2_rmp_pins_a>;
       pinctrl-names = "default";
     };
 
-- 
2.25.1