boards: shields: Add Sparkfun RV8803 RTC shield

Product photo from
https://www.sparkfun.com/sparkfun-real-time-clock-module-rv-8803-qwiic.html

Tested with the command mentioned in the index.rst page.

Signed-off-by: Jonas Berg <[email protected]>

Author: pyhys

boards/shields/sparkfun_rv8803/Kconfig.shield

@@ -0,0 +1,5 @@
+# Copyright (c) 2025 Jonas Berg
+# SPDX-License-Identifier: Apache-2.0
+
+config SHIELD_SPARKFUN_RV8803
+	def_bool $(shields_list_contains,sparkfun_rv8803)

boards/shields/sparkfun_rv8803/doc/index.rst

@@ -0,0 +1,69 @@
+.. _sparkfun_rv8803:
+
+Sparkfun RV8803 Shield
+######################
+
+Overview
+********
+
+The `SparkFun RV8803 Real Time Clock Shield`_ features
+a `Micro Crystal RV-8803-C7 Real-Time-Clock`_ and two Qwiic connectors.
+It has a 3 Volt back-up coin-cell battery.
+
+.. figure:: sparkfun_rv8803.webp
+   :align: center
+   :alt: Sparkfun RV8803 Shield
+
+   Sparkfun RV8803 Shield (Credit: Sparkfun)
+
+
+Requirements
+************
+
+This shield can be used with boards which provide an I2C connector, for
+example STEMMA QT or Qwiic connectors.
+The target board must define a ``zephyr_i2c`` node label.
+See :ref:`shields` for more details.
+
+
+Pin Assignments
+===============
+
++--------------+-------------------------------------------------------------------------------------------------+
+| Shield Pin   | Function                                                                                        |
++==============+=================================================================================================+
+| SDA          | RV8803 I2C SDA. Also connected to the Qwiic connector.                                          |
++--------------+-------------------------------------------------------------------------------------------------+
+| SCL          | RV8803 I2C SCL. Also connected to the Qwiic connector.                                          |
++--------------+-------------------------------------------------------------------------------------------------+
+| EVI          | RV8803 event input. Active low by default, with external pull-up and on-shield button.          |
++--------------+-------------------------------------------------------------------------------------------------+
+| INT          | RV8803 interrupt output. Active low (open drain), with external pull-up.                        |
++--------------+-------------------------------------------------------------------------------------------------+
+| CLKOUT       | RV8803 clock output. 32768, 1024 or 1 Hz (controlled by devicetree setting). Enabled by CLKOE.  |
++--------------+-------------------------------------------------------------------------------------------------+
+| CLKOE        | RV8803 control of CLKOUT, which is enabled when this pin is high. External pull-down on shield. |
++--------------+-------------------------------------------------------------------------------------------------+
+
+To use the interrupt output from the RV-8803, you need to connect a wire from
+the shield INT output to a suitable GPIO on your microcontroller board, and to
+modify the devicetree settings. See :dtcompatible:`microcrystal,rv8803` for options.
+
+
+Programming
+***********
+
+Set ``--shield sparkfun_rv8803`` when you invoke ``west build``. For example
+when running the :zephyr:code-sample:`rtc` sample:
+
+.. zephyr-app-commands::
+   :zephyr-app: samples/drivers/rtc
+   :board: adafruit_qt_py_rp2040
+   :shield: sparkfun_rv8803
+   :goals: build
+
+.. _SparkFun RV8803 Real Time Clock Shield:
+   https://www.sparkfun.com/sparkfun-real-time-clock-module-rv-8803-qwiic.html
+
+.. _Micro Crystal RV-8803-C7 Real-Time-Clock:
+   https://www.microcrystal.com/en/products/real-time-clock-rtc-modules/rv-8803-c7

boards/shields/sparkfun_rv8803/doc/sparkfun_rv8803.webp

@@ -0,0 +1,10 @@
+# SPDX-License-Identifier: Apache-2.0
+#
+# Copyright (c) 2025, Jonas Berg
+
+shield:
+  name: sparkfun_rv8803
+  full_name: Sparkfun RV8803 Real Time Clock Shield
+  vendor: sparkfun
+  supported_features:
+    - rtc

boards/shields/sparkfun_rv8803/shield.yml

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2025 Jonas Berg
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+/ {
+	aliases {
+		rtc = &sparkfun_rv8803;
+	};
+};
+
+&zephyr_i2c {
+	status = "okay";
+
+	sparkfun_rv8803: rv8803@32 {
+		status = "okay";
+		compatible = "microcrystal,rv8803";
+		reg = <0x32>;
+	};
+};

boards/shields/sparkfun_rv8803/sparkfun_rv8803.overlay

@@ -6,8 +6,11 @@ tests:
       - stm32f3_disco
       - mimxrt700_evk/mimxrt798s/cm33_cpu0
       - mimxrt700_evk/mimxrt798s/cm33_cpu1
+      - adafruit_qt_py_rp2040/rp2040
     integration_platforms:
       - stm32f3_disco
+    extra_args:
+      - platform:adafruit_qt_py_rp2040/rp2040:SHIELD="sparkfun_rv8803"
     tags:
       - samples
       - rtc