cmake: find & use libgpiod

CMakeLists.txt

@@ -27,7 +27,7 @@ set(CMAKE_C_STANDARD 11)
 set(CMAKE_C_STANDARD_REQUIRED True)
 
 option(BUILD_DOC "Enable building documents" OFF)
-option(HAVE_LINUXGPIO "Enable Linux sysfs GPIO support" OFF)
+option(HAVE_LINUXGPIO "Enable Linux sysfs and libgpiod GPIO support" OFF)
 option(HAVE_LINUXSPI "Enable Linux SPI support" OFF)
 option(HAVE_PARPORT "Enable parallel port support" OFF)
 option(USE_EXTERNAL_LIBS "Use external libraries from AVRDUDE GitHub repositories" OFF)
@@ -125,6 +125,7 @@ if(USE_STATIC_LIBS)
     set(PREFERRED_LIBFTDI libftdi.a ftdi)
     set(PREFERRED_LIBFTDI1 libftdi1.a ftdi1)
     set(PREFERRED_LIBREADLINE libreadline.a)
+    set(PREFERRED_LIBGPIOD libgpiod.a gpiod)
 else()
     set(PREFERRED_LIBELF elf)
     set(PREFERRED_LIBUSB usb)
@@ -133,6 +134,7 @@ else()
     set(PREFERRED_LIBFTDI ftdi)
     set(PREFERRED_LIBFTDI1 ftdi1)
     set(PREFERRED_LIBREADLINE readline)
+    set(PREFERRED_LIBGPIOD gpiod)
 endif()
 
 # -------------------------------------
@@ -223,6 +225,16 @@ elseif(MSVC)
     set(HAVE_LIBREADLINE 1)
 endif()
 
+# -------------------------------------
+# Find libgpiod, if needed
+if(HAVE_LINUXGPIO)
+    find_library(HAVE_LIBGPIOD NAMES ${PREFERRED_LIBGPIOD})
+    if(HAVE_LIBGPIOD)
+        set(LIB_LIBGPIOD ${HAVE_LIBGPIOD})
+        set(CMAKE_REQUIRED_LIBRARIES ${LIB_LIBGPIOD})
+    endif()
+endif()
+
 # =====================================
 # Use external libraries if requested
 # =====================================
@@ -315,6 +327,7 @@ if (DEBUG_CMAKE)
     message(STATUS "HAVE_LIBUSB_1_0_LIBUSB_H: ${HAVE_LIBUSB_1_0_LIBUSB_H}")
     message(STATUS "HAVE_HIDAPI_HIDAPI_H: ${HAVE_HIDAPI_HIDAPI_H}")
     message(STATUS "LIBUSB_COMPAT_DIR: ${LIBUSB_COMPAT_DIR}")
+    message(STATUS "HAVE_LIBGPIOD: ${HAVE_LIBGPIOD}")
     message(STATUS "----------------------")
 endif()
 
@@ -378,6 +391,11 @@ endif()
 
 if(HAVE_LINUXGPIO)
     message(STATUS "ENABLED    linuxgpio")
+    if (HAVE_LIBGPIOD)
+        message(STATUS "DO HAVE    libgpiod")
+    else()
+        message(STATUS "DON'T HAVE libgpiod")
+    endif()
 else()
     message(STATUS "DISABLED   linuxgpio")
 endif()

src/CMakeLists.txt

@@ -272,6 +272,7 @@ target_link_libraries(libavrdude
     ${LIB_LIBFTDI1}
     ${LIB_LIBREADLINE}
     ${LIB_NCURSES}
+    ${LIB_LIBGPIOD}
     ${EXTRA_WINDOWS_LIBRARIES}
     )
 

src/cmake_config.h.in

@@ -27,6 +27,9 @@
 /* Linux sysfs GPIO support enabled */
 #cmakedefine HAVE_LINUXGPIO 1
 
+/* Let linuxgpio know if libgpiod is available. */
+#cmakedefine HAVE_LIBGPIOD
+
 /* Linux SPI support enabled */
 #cmakedefine HAVE_LINUXSPI 1