From 0178a847118618727e3667e6490b8a88d98acb7c Mon Sep 17 00:00:00 2001
From: Brendan <2bndy5@gmail.com>
Date: Sat, 23 Mar 2024 09:12:29 -0700
Subject: [PATCH] expose GPIO & interrupt functions in new digital_io module

---
 CMakeLists.txt            |  32 ++++++++--
 src/pyArduinoAPI.cpp      | 122 ++++++++++++++++++++++++++++++++++++++
 src/pyrf24/digital_io.pyi |  15 +++++
 3 files changed, 163 insertions(+), 6 deletions(-)
 create mode 100644 src/pyArduinoAPI.cpp
 create mode 100644 src/pyrf24/digital_io.pyi

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 18c3783..e823f64 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,23 +19,22 @@ if(NOT "${RF24_LINKED_DRIVER}" STREQUAL "")
 endif()
 
 # suplement our copy of linux/gpio.h into SPIDEV & RPi driver sources
-set(SUPPLEMEN_LINUX_GPIO_H FALSE)
+set(SUPPLEMENT_LINUX_GPIO_H FALSE)
 if("${RF24_DRIVER}" STREQUAL "RPi" OR "${RF24_DRIVER}" STREQUAL "SPIDEV")
-    set(SUPPLEMEN_LINUX_GPIO_H TRUE)
+    set(SUPPLEMENT_LINUX_GPIO_H TRUE)
     message(STATUS "Supplementing ${RF24_DRIVER} driver with linux/gpio.h")
     # file(COPY src/linux/gpio.h DESTINATION RF24/utility/${RF24_DRIVER}/linux)
     list(APPEND RF24_DRIVER_SOURCES src/linux/gpio.h)
 endif()
 
 ################################# RF24 #############################
-set(CMAKE_VERBOSE_MAKEFILE ON)
 pybind11_add_module(rf24 src/pyRF24.cpp)
 target_include_directories(rf24 PUBLIC
     RF24
     RF24/utility
     RF24/utility/${RF24_DRIVER}
 )
-if(SUPPLEMEN_LINUX_GPIO_H)
+if(SUPPLEMENT_LINUX_GPIO_H)
     target_include_directories(rf24 PUBLIC src)
 endif()
 target_sources(rf24 PUBLIC
@@ -56,7 +55,7 @@ target_include_directories(rf24_network PUBLIC
     RF24/utility
     RF24/utility/${RF24_DRIVER}
 )
-if(SUPPLEMEN_LINUX_GPIO_H)
+if(SUPPLEMENT_LINUX_GPIO_H)
     target_include_directories(rf24_network PUBLIC src)
 endif()
 # don't let source look for an installed RF24 lib
@@ -84,7 +83,7 @@ target_include_directories(rf24_mesh PUBLIC
     RF24/utility
     RF24/utility/${RF24_DRIVER}
 )
-if(SUPPLEMEN_LINUX_GPIO_H)
+if(SUPPLEMENT_LINUX_GPIO_H)
     target_include_directories(rf24_mesh PUBLIC src)
 endif()
 # don't let source look for an installed RF24 lib
@@ -104,6 +103,23 @@ target_sources(rf24_mesh PUBLIC
 )
 apply_flags(rf24_mesh)
 
+################################# Arduino DigitalIO #############################
+
+pybind11_add_module(digital_io src/pyArduinoAPI.cpp)
+target_include_directories(digital_io PUBLIC
+    RF24
+    RF24/utility
+    RF24/utility/${RF24_DRIVER}
+)
+if(SUPPLEMENT_LINUX_GPIO_H)
+    target_include_directories(digital_io PUBLIC src)
+endif()
+# don't let source look for an installed RF24 lib
+target_compile_definitions(digital_io PUBLIC USE_RF24_LIB_SRC)
+target_sources(digital_io PUBLIC
+    ${RF24_DRIVER_SOURCES}
+)
+apply_flags(digital_io)
 
 ################################ INSTALL RULES ####################################
 # these are needed for scikit builds since the resulting .so files are copied into
@@ -111,3 +127,7 @@ apply_flags(rf24_mesh)
 install(TARGETS rf24 DESTINATION .)
 install(TARGETS rf24_network DESTINATION .)
 install(TARGETS rf24_mesh DESTINATION .)
+install(TARGETS digital_io DESTINATION .)
+
+# uncomment to show compiler args used in build logs
+# set(CMAKE_VERBOSE_MAKEFILE ON)
diff --git a/src/pyArduinoAPI.cpp b/src/pyArduinoAPI.cpp
new file mode 100644
index 0000000..63f1d7b
--- /dev/null
+++ b/src/pyArduinoAPI.cpp
@@ -0,0 +1,122 @@
+#include <pybind11/pybind11.h>
+#include <pybind11/functional.h>
+#include <RF24.h> // The public API will pull in the backend hardware interface for GPIO
+
+namespace py = pybind11;
+
+#ifndef HIGH
+static const int HIGH = 1;
+#endif
+#ifndef LOW
+static const int LOW = 0;
+#endif
+
+PYBIND11_MODULE(digital_io, m)
+{
+    m.doc() = "Some Arduino-style API used to expose GPIO interface for digital input and outputs";
+
+    // ******************************************** General GPIO
+    m.attr("HIGH") = HIGH;
+    m.attr("LOW") = LOW;
+    m.attr("INPUT") = INPUT;
+    m.attr("OUTPUT") = OUTPUT;
+
+    m.def("pinMode", &GPIO::open, R"docstr(
+        pinMode(pin: int, direction: int) -> None
+
+        Initialize a GPIO pin.
+
+        :param pin: The pin number to initialize.
+        :param direction: The direction of the initialized pin.
+            This only be either `INPUT` or `OUTPUT`.
+    )docstr",
+          py::arg("pin"), py::arg("direction"));
+    m.def("pinClose", &GPIO::close, R"docstr(
+        pinClose(pin: int) -> None
+
+        Deinitialize a GPIO pin.
+
+        :param pin: The pin number to deinitialize.
+    )docstr",
+          py::arg("pin"));
+    m.def("digitalWrite", &GPIO::write, R"docstr(
+        digitalWrite(pin: int, value: int) -> None
+
+        Write a digital output value to a GPIO pin.
+
+        :param pin: The pin number to manipulate (as an output).
+        :param value: The value set to the output pin.
+            This can only be either `HIGH` or `LOW`.
+    )docstr",
+          py::arg("pin"), py::arg("value"));
+
+    m.def("digitalRead", &GPIO::read, R"docstr(
+        digitalRead(pin: int) -> int
+
+        Read the current value of a given pin.
+
+        :param pin: The GPIO input pin to read.
+
+        :returns:
+            ``1`` if the pin is currently `HIGH`, ``0`` if the pin is currently `LOW`.
+    )docstr",
+          py::arg("pin"));
+
+#ifndef MRAA
+
+    // ******************************************** Interrupt support
+
+    #ifndef RF24_WIRINGPI
+    m.def("detachInterrupt", &detachInterrupt, R"docstr(
+        detachInterrupt(pin: int)
+
+        Discontinue watching the given GPIO input ``pin`` for an event. This is similar to
+        `pinClose()` but also deallocates the background thread used to monitor the pin for
+        events.
+
+        .. note::
+            This function is only available for the SPIDEV and RPi drivers.
+            It is not exposed when the pyrf24 package is built (from source) with the MRAA or
+            wiringPi drivers.
+
+        :param pin: The pin number to watch for events described by ``mode``.
+
+        :returns:
+            ``1`` if the pin was un-initialized and the background thread was canceled,
+            ``0`` if there was nothing to do.
+    )docstr",
+          py::arg("pin"));
+    #endif // !defined(RF24_WIRINGPI)
+
+    m.attr("FALLING") = INT_EDGE_FALLING;
+    m.attr("RISING") = INT_EDGE_RISING;
+    m.attr("CHANGE") = INT_EDGE_BOTH;
+    m.def(
+        "attachInterrupt", [](rf24_gpio_pin_t pin, int mode, std::function<void(void)>& func) {
+            return attachInterrupt(pin, mode, *func.target<void (*)()>());
+        },
+        R"docstr(
+        attachInterrupt(pin: int, mode: int, function: Callable[[], None]) -> int
+
+        Attach an Interrupt Service Routine (ISR), a callback function, to a GPIO input pin.
+
+        .. note::
+            This function is only available for the SPIDEV, RPi, and wiringPi drivers.
+            It is not exposed when the pyrf24 package is built (from source) with the MRAA
+            driver.
+
+        :param pin: The pin number to watch for events described by ``mode``.
+        :param mode: The event type that triggers a call to the given ``function``.
+            This value can only be `FALLING`, `RISING`, or `CHANGE`.
+        :param function: The function to call when an event (described by ``mode``) occurs on
+            the specified ``pin``. This function signature expects no arguments and returns
+            nothing.
+        
+        :returns:
+            ``1`` if pin is successfully setup to watch for an event, ``0`` if the given ``mode``
+            is malformed. If ``0`` is returned, then specified pin remains un-initialized.
+    )docstr",
+        py::arg("pin"), py::arg("mode"), py::arg("function"));
+
+#endif // !defined(MRAA)
+};
diff --git a/src/pyrf24/digital_io.pyi b/src/pyrf24/digital_io.pyi
new file mode 100644
index 0000000..0c7c332
--- /dev/null
+++ b/src/pyrf24/digital_io.pyi
@@ -0,0 +1,15 @@
+from typing import Callable
+
+INPUT: int = ...
+OUTPUT: int = ...
+HIGH: int = ...
+LOW: int = ...
+
+FALLING: int = ...
+RISING: int = ...
+CHANGE: int = ...
+
+def pinMode(pin: int, mode: int) -> None: ...
+def pinClose(pin: int) -> None: ...
+def detachInterrupt(pin: int) -> None: ...
+def attachInterrupt(pin, int, mode: int, function: Callable[[], None]) -> int: ...