Feat/support rpi5 (#5)

SimonCahill · web-flow · commit d5f7a6e39241 · 2024-12-04T18:25:06.000+01:00
* Updated version and added install target

* Added fallback GPIO chip for RPi5

* From merge

* Updated README

* Fixed compiler errors.
diff --git a/README.md b/README.md
@@ -2,6 +2,68 @@
 This repository contains example code useful when using the WaveShare 8-channel relay module for the RaspberryPi.
 The example code provided by WaveShare is mixed up and doesn't work correctly.
 
+# C++ Application
+
+Included with this repository is a C++ application, which is now the recommended use of this repository!  
+The C++ application uses libgpiod, which is bundled in this repository. Regardless of whether or not libgpiod is found on your system,  
+the Makefile generator will always download the correct version of the library and link against it.
+
+## Building the Application
+
+Unlike in previous versions, the application has been refactored to use CMake as its Makefile generator and build system, instead of using raw compiler commands.  
+Building the application is very easy nonetheless.
+
+```sh
+# Ensure you're in the `cpp` directory!
+
+# Create build directory
+mkdir -p build && cd build
+
+# It doesn't really matter which platform you're on; because of the fallback logic, this should work on both RPi5 and older models
+
+cmake .. [-Dchannelselect_RASPI5] # Add the value in brackets if you're planning on running on RPi5.
+
+make -j$(($(nproc)-1)) # Build with nproc - 1
+```
+
+## Usage
+
+Using the app is fairly simple, and it provides a simple help text to get you started.  
+Some examples are included below:
+
+```
+waveshare_channel_select v1.1.0 - A simple application for controlling GPIO pins on modern Linux OSs on RasPi
+
+Usage:
+    waveshare_channel_select -h
+    waveshare_channel_select -e -123       # enable channels 1, 2, and 3
+    waveshare_channel_select -d -528       # disable channels 5, 2, and 8 and read the state of channel 7
+    waveshare_channel_select -L            # read the states of all channels
+
+Troubleshooting:
+    Permission denied? Is your user in the gpio group? # usermod -aG gpio <myuser>
+    Library not found? Try installing lgpiod
+
+Options:
+    Channel selection:
+     --channel1,    -1  Channel 1
+     --channel2,    -2  Look, it's the same up until -8
+     ...
+     --channel8,    -8  I'm sure it's self-explanatory at this point
+     --all,         -a  All channels
+
+    Channel options:
+     --enable,      -e  Enable channel(s)
+     --disable,     -d  Disable channel(s)
+     --read,        -r  Read the channel state
+
+    General options:
+     --list-all,    -L  List all channels and their current state
+
+     --help,        -h  Displays this text and exits
+     --version,     -v  Displays the version information and exits
+```
+
 # Bash Script
 
 Contained within this repository is a Bash script, which handles setting the GPIO pins, respective to the selected channel.
@@ -32,21 +94,4 @@ If the --help|-h arg is passed, the script will print the help text and exit.
 
 # Print help menu
 ./channel_select --help
-```
-
-# C++ Application
-
-Provided with this repository is a simple sample application written in C++, providing the same functionality as the Bash script.
-
-## Building
-
-```
-g++ -std=c++17 -o channel_select cpp/channel_select.cpp
-```
-
-## Usage
-
-The C++ example provides the same features/functionality and arguments as the Bash script.<br >
-They are virtually 1:1 ports of each other.
-
-
+```
diff --git a/cpp/CMakeLists.txt b/cpp/CMakeLists.txt
@@ -1,6 +1,6 @@
 cmake_minimum_required(VERSION 3.20)
 
-project(waveshare_channel_select LANGUAGES CXX VERSION 1.1.0)
+project(waveshare_channel_select LANGUAGES CXX VERSION 1.2.0)
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
 
@@ -15,6 +15,14 @@ else()
     )
 endif()
 
+if (DEFINED channelselect_RASPI5)
+    set(DEFAULT_GPIOCHIP "gpiochip4")
+    set(FALLBACK_GPIOCHIP "gpiochip0")
+    else()
+    set(DEFAULT_GPIOCHIP "gpiochip0")
+    set(FALLBACK_GPIOCHIP "gpiochip4")
+endif()
+
 add_compile_options(
     -Werror
     -Wall
@@ -43,4 +51,13 @@ target_link_libraries(
     gpiod::shared
     gpiodcxx::shared
     fmt
+)
+
+###
+# Define install target
+# This will install the executable to /usr/local/bin
+###
+install(
+    TARGETS channel_select
+    DESTINATION ${CMAKE_INSTALL_BINDIR}
 )
diff --git a/cpp/channel_select.cpp b/cpp/channel_select.cpp
@@ -84,9 +84,9 @@ using optsm_t = optional<StateModifier>;
 optsm_t     stateModifierFromString(const string& optArg); //!< Converts an optarg value to a boolean
 int32_t     parseArgs(int32_t argc, char** argv); //!< Parses arguments passed to the application
 
-bool        getChannelState(const int32_t channelId); //!< Gets the state of a given channel
+bool        getChannelState(const int32_t channelId, const string& gpioDevice = GPIO_CHIP); //!< Gets the state of a given channel
 void        listChannels(); //!< Lists all channels available with their state.
-void        setChannel(const int32_t channelId, const StateModifier newState); //!< Sets the state of a given channel
+void        setChannel(const int32_t channelId, const StateModifier newState, const string& gpioDevice = GPIO_CHIP); //!< Sets the state of a given channel
 
 void        printHelp(); //!< Prints the help text for the application
 void        printVersion(); //!< Prints the version information for the application
@@ -197,12 +197,17 @@ int32_t parseArgs(int32_t argc, char** argv) {
     return 0;
 }
 
-bool getChannelState(const int32_t channel) {
-    auto gpioChip = gpiod::chip(string{GPIO_CHIP});
-    auto lineSettings = gpiod::line_settings{};
-    auto line = gpioChip.prepare_request().add_line_settings(gpioChip.get_line_offset_from_name(fmt::format("GPIO{0:d}", channel)), lineSettings).do_request();
+bool getChannelState(const int32_t channel, const string& gpioDevice/* = GPIO_CHIP*/) {
 
-    return static_cast<bool>(line.get_value(line.offsets()[0]));
+    try {
+        auto gpioChip = gpiod::chip(string{gpioDevice});
+        auto lineSettings = gpiod::line_settings{};
+        auto line = gpioChip.prepare_request().add_line_settings(gpioChip.get_line_offset_from_name(fmt::format("GPIO{0:d}", channel)), lineSettings).do_request();
+
+        return static_cast<bool>(line.get_value(line.offsets()[0]));
+    } catch (const std::invalid_argument&) {
+        return getChannelState(channel, FALLBACK_GPIO_CHIP);
+    }
 }
 
 optsm_t stateModifierFromString(const string& optArg) {
@@ -271,14 +276,19 @@ void printVersion() {
     fmt::print(R"({0:s} v{1:s} - A simple application for controlling GPIO pins on modern Linux OSs on RasPi)", APP_NAME, APP_VERS);
 }
 
-void setChannel(const int32_t channel, const StateModifier newState) {
+void setChannel(const int32_t channel, const StateModifier newState, const string& gpioDevice/* = GPIO_CHIP*/) {
     const auto gpioLineName = fmt::format("GPIO{0:d}", CHANNELS[channel]);
 
-    auto gpioChip = gpiod::chip(string{GPIO_CHIP});
-    auto lineSettings = gpiod::line_settings{};
-    lineSettings.set_direction(gpiod::line::direction::OUTPUT);
-    auto line = gpioChip.prepare_request().add_line_settings(gpioChip.get_line_offset_from_name(gpioLineName), lineSettings).do_request();
-
-    fmt::println("Attempting to set GPIO{0:d} {1:s}", CHANNELS[channel], newState == StateModifier::DISABLE ? "ON" : "OFF");
-    line.set_value(line.offsets()[0], newState == StateModifier::DISABLE ? gpiod::line::value::INACTIVE : gpiod::line::value::ACTIVE);
+    try {
+        auto gpioChip = gpiod::chip(string{gpioDevice});
+        auto lineSettings = gpiod::line_settings{};
+        lineSettings.set_direction(gpiod::line::direction::OUTPUT);
+        auto line = gpioChip.prepare_request().add_line_settings(gpioChip.get_line_offset_from_name(gpioLineName), lineSettings).do_request();
+        
+        fmt::println("Attempting to set GPIO{0:d} {1:s}", CHANNELS[channel], newState == StateModifier::DISABLE ? "ON" : "OFF");
+        line.set_value(line.offsets()[0], newState == StateModifier::DISABLE ? gpiod::line::value::INACTIVE : gpiod::line::value::ACTIVE);
+    } catch (const std::invalid_argument&) {
+        setChannel(channel, newState, FALLBACK_GPIO_CHIP);
+        return;
+    }
 }
diff --git a/cpp/channel_select.in.hpp b/cpp/channel_select.in.hpp
@@ -14,6 +14,6 @@
 constexpr const char* APP_NAME = "@PROJECT_NAME@";
 constexpr const char* APP_VERS = "@PROJECT_VERSION@";
 
-constexpr const char* GPIO_CHIP = "/dev/gpiochip0"; //!< This is the chip required for controlling the relay board
-
+constexpr const char* GPIO_CHIP = "/dev/@DEFAULT_GPIOCHIP@"; //!< This is the chip required for controlling the relay board
+constexpr const char* FALLBACK_GPIO_CHIP = "/dev/@FALLBACK_GPIOCHIP@"; //!< This is the fallback chip required for controlling the relay board on a RaspberrFALLBACK
 #endif // CHANNEL_SELECT_HPP
diff --git a/cpp/cmake/add_libgpiod.cmake b/cpp/cmake/add_libgpiod.cmake
@@ -6,6 +6,8 @@ ExternalProject_Add(
     SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/submodules/libgpiod
     CONFIGURE_COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/submodules/libgpiod/autogen.sh --enable-bindings-cxx --prefix ${CMAKE_CURRENT_BINARY_DIR}/libgpiod/
 
+    UPDATE_COMMAND cd ${CMAKE_CURRENT_SOURCE_DIR}/submodules/libgpiod && autoupdate
+
     # BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/libgpiod
     BUILD_COMMAND make
 )

Original file line number	Diff line number	Diff line change
`@@ -6,6 +6,8 @@ ExternalProject_Add(`
`6`	`6`	`SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/submodules/libgpiod`
`7`	`7`	`CONFIGURE_COMMAND ${CMAKE_CURRENT_SOURCE_DIR}/submodules/libgpiod/autogen.sh --enable-bindings-cxx --prefix ${CMAKE_CURRENT_BINARY_DIR}/libgpiod/`
`8`	`8`
	`9`	`+ UPDATE_COMMAND cd ${CMAKE_CURRENT_SOURCE_DIR}/submodules/libgpiod && autoupdate`
	`10`	`+`
`9`	`11`	`# BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR}/libgpiod`
`10`	`12`	`BUILD_COMMAND make`
`11`	`13`	`)`