IRQ support using Linux kernel Character Device + Posix threads

.github/workflows/build_linux.yml

@@ -68,7 +68,7 @@ jobs:
           - "--driver=SPIDEV"
           - "--driver=MRAA"
           - "--driver=pigpio"
-          # - "--soc=BCM2835 --driver=wiringPi"
+          - "--soc=BCM2835 --driver=wiringPi"
 
     env:
       CFLAGS: "-I /usr/local/include"
@@ -133,9 +133,6 @@ jobs:
         run: sudo make install
 
       - name: make linux examples
-        # compiling examples for wiringPi is broken see issue #669
-        # executables linked to wiringPi additionally need to be linked to crypt and shm_open
-        # interruptConfigure.cpp example is incompatible with MRAA & wiringPi drivers
         if: ${{ matrix.config-options != '--soc=BCM2835 --driver=wiringPi' && matrix.config-options != '--driver=MRAA' }}
         run: |
           cd examples_linux

CMakeLists.txt

@@ -137,17 +137,12 @@ if(DEFINED RF24_SPI_SPEED)
     )
 endif()
 # allow user customization of default GPIO chip used with the SPIDEV driver
-if(DEFINED RF24_SPIDEV_GPIO_CHIP)
-    message(STATUS "RF24_SPIDEV_GPIO_CHIP set to ${RF24_SPIDEV_GPIO_CHIP}")
+if(DEFINED RF24_LINUX_GPIO_CHIP)
+    message(STATUS "RF24_LINUX_GPIO_CHIP set to ${RF24_LINUX_GPIO_CHIP}")
     target_compile_definitions(${LibTargetName} PUBLIC
-        RF24_SPIDEV_GPIO_CHIP="${RF24_SPIDEV_GPIO_CHIP}"
+        RF24_LINUX_GPIO_CHIP="${RF24_LINUX_GPIO_CHIP}"
     )
 endif()
-# conditionally disable interruot support (a pigpio specific feature)
-if("${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND" OR DEFINED RF24_NO_INTERRUPT)
-    message(STATUS "Disabling IRQ pin support")
-    target_compile_definitions(${LibTargetName} PUBLIC RF24_NO_INTERRUPT)
-endif()
 
 
 #####################################

Makefile

@@ -21,15 +21,9 @@ OBJECTS=RF24.o
 ifeq ($(DRIVER), MRAA)
 OBJECTS+=spi.o gpio.o compatibility.o
 else ifeq ($(DRIVER), RPi)
-OBJECTS+=spi.o bcm2835.o compatibility.o
-ifneq (,$(findstring -lpigpio,$(SHARED_LINKER_LIBS)))
-OBJECTS+=interrupt.o
-endif
+OBJECTS+=spi.o bcm2835.o compatibility.o interrupt.o
 else ifeq ($(DRIVER), SPIDEV)
-OBJECTS+=spi.o gpio.o compatibility.o
-ifneq (,$(findstring -lpigpio,$(SHARED_LINKER_LIBS)))
-OBJECTS+=interrupt.o
-endif
+OBJECTS+=spi.o gpio.o compatibility.o interrupt.o
 else ifeq ($(DRIVER), wiringPi)
 OBJECTS+=spi.o
 else ifeq ($(DRIVER), pigpio)

configure

@@ -3,8 +3,6 @@
 CROSS_CC=arm-linux-gnueabihf-gcc
 CROSS_CXX=arm-linux-gnueabihf-g++
 
-pigpio_detected=0
-
 function help {
 cat <<EOF
 configure script for RF24 library.
@@ -58,11 +56,6 @@ function execute_check {
     fi
 }
 
-if [[ -f "/usr/lib/libpigpio.so" || -f "/usr/local/lib/libpigpio.so" || -f "/usr/arm-linux-gnueabihf/lib/libpigpio.so" ]]; then
-    echo "[INFO] pigpio lib found."
-    pigpio_detected=1
-fi
-
 function die {
     echo "[ERROR] $1"
     exit $2
@@ -192,7 +185,7 @@ function detect_driver {
         result=MRAA
     elif [[ $(execute_check "${REMOTE_LDCONFIG} -p | grep liblittlewire-spi") ]]; then
         result=LittleWire
-    elif [ $pigpio_detected -eq 1 ]; then
+    elif [[ -f "/usr/lib/libpigpio.so" || -f "/usr/local/lib/libpigpio.so" || -f "/usr/arm-linux-gnueabihf/lib/libpigpio.so" ]]; then
         result=pigpio
     else
         result=""
@@ -407,24 +400,12 @@ fi
 
 case ${DRIVER} in
 wiringPi)
-    SHARED_LINKER_LIBS+=" -lpigpio -lwiringPi"
+    SHARED_LINKER_LIBS+=" -lwiringPi"
     CFLAGS+=" -lwiringPi"
     ;;
 SPIDEV)
-    if [ $pigpio_detected -eq 1 ]; then
-        echo "[INFO] linking to pigpio for interrupt compatibility"
-        SHARED_LINKER_LIBS+=" -lpigpio"
-    else
-        CFLAGS+=" -DRF24_NO_INTERRUPT"
-    fi
     ;;
 RPi)
-    if [ $pigpio_detected -eq 1 ]; then
-        echo "[INFO] linking to pigpio for interrupt compatibility"
-        SHARED_LINKER_LIBS+=" -lpigpio"
-    else
-        CFLAGS+=" -DRF24_NO_INTERRUPT"
-    fi
     ;;
 MRAA)
     SHARED_LINKER_LIBS+=" -lmraa"
@@ -433,11 +414,7 @@ LittleWire)
     SHARED_LINKER_LIBS+=" -llittlewire-spi"
     ;;
 pigpio)
-    if [ $pigpio_detected -eq 0 ]; then
-        die "[ERROR] pigpio was not detected. Make sure pigpio is installed." 2
-    else
-        SHARED_LINKER_LIBS+=" -lpigpio"
-    fi
+    SHARED_LINKER_LIBS+=" -lpigpio"
     ;;
 *)
     die "Unsupported DRIVER: ${DRIVER}." 2

examples_linux/CMakeLists.txt

@@ -24,7 +24,7 @@ find_library(RF24 rf24 REQUIRED)
 message(STATUS "using RF24 library: ${RF24}")
 
 # conditionally append "interruptConfigure" to the EXAMPLES_LIST
-if("${RF24_DRIVER}" STREQUAL "MRAA" OR "${RF24_DRIVER}" STREQUAL "wiringPi" OR "${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND")
+if("${RF24_DRIVER}" STREQUAL "MRAA")
     message(STATUS "Skipping interruptConfigure.cpp example as it is incompatible with selected driver library")
 else() # not using MRAA or wiringPi drivers (or pigpio lib was found)
     list(APPEND EXAMPLES_LIST interruptConfigure)
@@ -52,26 +52,15 @@ elseif("${RF24_DRIVER}" STREQUAL "wiringPi")
     else()
         message(FATAL "Lib ${RF24_DRIVER} not found.")
     endif()
-elseif(NOT "${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND" AND NOT DEFINED RF24_NO_INTERUPT)
-    if(NOT "${RF24_DRIVER}" STREQUAL "pigpio")
-        message(STATUS "linking to ${LibPIGPIO} for interrupt support")
-    else()
-        message(STATUS "linking to ${LibPIGPIO}")
-    endif()
+elseif(NOT "${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND")
+    message(STATUS "linking to ${LibPIGPIO}")
     # linking to pigpio requires pthread to be listed as last linked lib
     list(APPEND linked_libs ${LibPIGPIO} pthread)
-else()
-    message(STATUS "Disabling IRQ pin support")
 endif()
 
 foreach(example ${EXAMPLES_LIST})
     #make a target
     add_executable(${example} ${example}.cpp)
-
-    # avoid including interrupt.h when pigpio is not available
-    if("${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND" OR DEFINED RF24_NO_INTERRUPT)
-        target_compile_definitions(${example} PUBLIC RF24_NO_INTERRUPT)
-    endif()
 
     target_link_libraries(${example} PUBLIC ${linked_libs})
 endforeach()

examples_linux/Makefile

@@ -19,7 +19,7 @@ include ../Makefile.inc
 
 # define all programs
 PROGRAMS = gettingstarted acknowledgementPayloads manualAcknowledgements streamingData multiceiverDemo scanner
-ifneq (,$(findstring -lpigpio,$(SHARED_LINKER_LIBS)))
+ifneq ($(DRIVER), MRAA)
 PROGRAMS+=interruptConfigure
 endif
 

examples_linux/Makefile.examples

@@ -17,6 +17,8 @@ SOURCES = $(PROGRAMS:=.cpp)
 LIBS=-l$(LIB)
 ifeq ($(DRIVER), LittleWire)
 	LIBS+= -llittlewire-spi
+else ifeq ($(DRIVER), wiringPi)
+	LIBS+= -lwiringPi -lcrypt -lrt
 endif
 
 all: $(PROGRAMS)

examples_linux/interruptConfigure.cpp

@@ -22,7 +22,7 @@
 using namespace std;
 
 // We will be using the nRF24L01's IRQ pin for this example
-#define IRQ_PIN 12 // this needs to be a digital input capable pin
+#define IRQ_PIN 24 // this needs to be a digital input capable pin
 
 // this example is a sequential program. so we need to wait for the event to be handled
 volatile bool got_interrupt = false; // used to signify that the event started
@@ -167,14 +167,14 @@ void master()
     // Test the "data ready" event with the IRQ pin
     cout << "\nConfiguring IRQ pin to ignore the 'data sent' event\n";
     radio.maskIRQ(true, false, false); // args = "data_sent", "data_fail", "data_ready"
-    cout << "   Pinging RX node for 'data ready' event...";
+    cout << "   Pinging RX node for 'data ready' event..." << endl;
     ping_n_wait(); // transmit a payload and detect the IRQ pin
     pl_iterator++; // increment iterator for next test
 
     // Test the "data sent" event with the IRQ pin
     cout << "\nConfiguring IRQ pin to ignore the 'data ready' event\n";
     radio.maskIRQ(false, false, true); // args = "data_sent", "data_fail", "data_ready"
-    cout << "   Pinging RX node for 'data sent' event...";
+    cout << "   Pinging RX node for 'data sent' event..." << endl;
     radio.flush_tx(); // flush payloads from any failed prior test
     ping_n_wait();    // transmit a payload and detect the IRQ pin
     pl_iterator++;    // increment iterator for next test
@@ -196,7 +196,7 @@ void master()
     // test the "data fail" event with the IRQ pin
     cout << "\nConfiguring IRQ pin to reflect all events\n";
     radio.maskIRQ(0, 0, 0); // args = "data_sent", "data_fail", "data_ready"
-    cout << "   Pinging inactive RX node for 'data fail' event...";
+    cout << "   Pinging inactive RX node for 'data fail' event..." << endl;
     ping_n_wait(); // transmit a payload and detect the IRQ pin
 
     // CE pin is still HIGH which consumes more power. Example is now idling so...
@@ -250,7 +250,12 @@ void ping_n_wait()
     // use the non-blocking call to write a payload and begin transmission
     // the "false" argument means we are expecting an ACK packet response
     radio.startFastWrite(tx_payloads[pl_iterator], tx_pl_size, false);
+    uint32_t timer = millis();
     while (!got_interrupt) {
+        if (millis() - timer > 500) {
+            cout << "\tIRQ NOT received" << endl;
+            break;
+        }
         /*
          * IRQ pin is LOW when activated. Otherwise it is always HIGH
          * Wait in this empty loop until IRQ pin is activated.

examples_linux/ncurses/CMakeLists.txt

@@ -18,6 +18,3 @@ target_link_libraries(${example} PUBLIC
     ${linked_libs}
     ${CURSES_LIBRARIES}
 )
-if("${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND" OR DEFINED RF24_NO_INTERRUPT)
-    target_compile_definitions(${example} PUBLIC RF24_NO_INTERRUPT)
-endif()

examples_linux/readme.md

@@ -1,3 +1,3 @@
 Note: These examples were originally designed for RPi, but should work on any supported Linux platform, with the proper pin configuration.
 
-See http://tmrh20.github.io/RF24 for more information
+See http://nRF24.github.io/RF24 for more information

pyRF24/setup.py

@@ -35,7 +35,6 @@
                 os.environ[identifier] = value
 
 except FileNotFoundError:  # assuming lib was built & installed with CMake
-
     # get LIB_VERSION from library.properties file for Arduino IDE
     with open(os.path.join(git_dir, "library.properties"), "r", encoding="utf-8") as f:
         for line in f.read().splitlines():
@@ -44,7 +43,6 @@
 
 # check C++ RF24 lib is installed
 finally:
-
     # check for possible linker flags set via CFLAGS environment variable
     for flag in cflags.split("-"):
         if flag.startswith("L"):
@@ -71,13 +69,6 @@
             )
         )
 
-    # avoid IRQ support if pigpio is not available; link to pigpio if it is found
-    found_pigpio = False
-    for symlink_loc in symlink_directory:
-        if os.path.exists(symlink_loc + "/libpigpio.so"):
-            found_pigpio = True
-    # IRQ pin features will be implemented in python via pigpio's python API or RPi.GPIO
-    cflags += " -DRF24_NO_INTERRUPT"
 
 # append any additionally found compiler flags
 os.environ["CFLAGS"] = cflags
@@ -114,7 +105,7 @@
         Extension(
             "RF24",
             sources=["pyRF24.cpp"],
-            libraries=["rf24", BOOST_LIB] + (["pigpio"] if found_pigpio else [])
+            libraries=["rf24", BOOST_LIB],
         )
     ],
 )

utility/CMakeLists.txt

@@ -8,12 +8,14 @@ if ("${RF24_DRIVER}" STREQUAL  "wiringPi") # Use wiringPi
         ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
         ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
         ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/interrupt.h
         PARENT_SCOPE
     )
     install(FILES
             ${RF24_DRIVER}/includes.h
             ${RF24_DRIVER}/spi.h
             ${RF24_DRIVER}/RF24_arch_config.h
+            ${RF24_DRIVER}/interrupt.h
         DESTINATION include/RF24/utility/${RF24_DRIVER}
     )
 elseif("${RF24_DRIVER}" STREQUAL "RPi") # use RPi
@@ -23,34 +25,18 @@ elseif("${RF24_DRIVER}" STREQUAL "RPi") # use RPi
             ${RF24_DRIVER}/spi.h
             ${RF24_DRIVER}/compatibility.h
             ${RF24_DRIVER}/RF24_arch_config.h
+            ${RF24_DRIVER}/interrupt.h
         DESTINATION include/RF24/utility/${RF24_DRIVER}
     )
-    if(NOT "${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND" AND NOT DEFINED RF24_NO_INTERRUPT)
-        set(RF24_LINKED_DRIVER ${LibPIGPIO} PARENT_SCOPE)
-        message(STATUS "linking to pigpio lib for interrupt functionality")
-        install(FILES
-                ${RF24_DRIVER}/interrupt.h
-            DESTINATION include/RF24/utility/${RF24_DRIVER}
-        )
-        set(RF24_DRIVER_SOURCES
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/bcm2835.c
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/compatibility.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/interrupt.cpp
-            PARENT_SCOPE
-        )
-    else()
-        set(RF24_DRIVER_SOURCES
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/bcm2835.c
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/compatibility.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
-            PARENT_SCOPE
-        )
-    endif()
+    set(RF24_DRIVER_SOURCES
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/bcm2835.c
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/compatibility.cpp
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/interrupt.cpp
+        PARENT_SCOPE
+    )
 elseif("${RF24_DRIVER}" STREQUAL "SPIDEV") # use SPIDEV
     if(NOT SPIDEV_EXISTS)
         message(WARNING "Detecting /dev/spidev0.0 failed - continuing anyway. Please make sure SPI is enabled.")
@@ -61,34 +47,18 @@ elseif("${RF24_DRIVER}" STREQUAL "SPIDEV") # use SPIDEV
             ${RF24_DRIVER}/spi.h
             ${RF24_DRIVER}/compatibility.h
             ${RF24_DRIVER}/RF24_arch_config.h
+            ${RF24_DRIVER}/interrupt.h
         DESTINATION include/RF24/utility/${RF24_DRIVER}
     )
-    if(NOT "${LibPIGPIO}" STREQUAL "LibPIGPIO-NOTFOUND" AND NOT DEFINED RF24_NO_INTERRUPT)
-        set(RF24_LINKED_DRIVER ${LibPIGPIO} PARENT_SCOPE)
-        message(STATUS "linking to pigpio lib for interrupt functionality")
-        install(FILES
-                ${RF24_DRIVER}/interrupt.h
-            DESTINATION include/RF24/utility/${RF24_DRIVER}
-        )
-        set(RF24_DRIVER_SOURCES
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/gpio.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/compatibility.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/interrupt.cpp
-            PARENT_SCOPE
-        )
-    else()
-        set(RF24_DRIVER_SOURCES
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/gpio.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/compatibility.cpp
-            ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
-            PARENT_SCOPE
-        )
-    endif()
+    set(RF24_DRIVER_SOURCES
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/includes.h
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/gpio.cpp
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/spi.cpp
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/compatibility.cpp
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/RF24_arch_config.h
+        ${CMAKE_CURRENT_LIST_DIR}/${RF24_DRIVER}/interrupt.cpp
+        PARENT_SCOPE
+    )
 elseif("${RF24_DRIVER}" STREQUAL "MRAA") # use MRAA
     set(RF24_LINKED_DRIVER ${LibMRAA} PARENT_SCOPE)
     set(RF24_DRIVER_SOURCES