Can't build it. Looks like -lgphoto2_port is missing at linking stage.
Can't find where GPHOTO2_LIBRARIES is set anyway :/

Linking CXX executable digikam
cd /home/users/arekm/rpm/BUILD/digikam-1.6.0/build/digikam && /usr/bin/cmake -E cmake_link_script CMakeFiles/digikam.dir/link.txt --verbose=1
/usr/bin/x86_64-pld-linux-g++ -O2 -fno-strict-aliasing -fwrapv -march=x86-64 -gdwarf-3 -g2 -Wnon-virtual-dtor -Wno-long-long -ansi -Wundef -Wcast-align -Wchar-subscripts -Wall -W -Wpointer-arith -Wformat-security -fno-exceptions -DQT_NO_EXCEPTIONS -fno-check-new -fno-common -Woverloaded-virtual -fno-threadsafe-statics -fvisibility=hidden -fvisibility-inlines-hidden -O2 -DNDEBUG -DQT_NO_DEBUG -Wl,--enable-new-dtags -Wl,--as-needed -Wl,--no-copy-dt-needed-entries -Wl,-z,relro -Wl,-z,combreloc CMakeFiles/digikam.dir/digikam_automoc.o CMakeFiles/digikam.dir/__/utilities/imageeditor/editor/imagewindow.o CMakeFiles/digikam.dir/__/libs/dialogs/deletedialog.o CMakeFiles/digikam.dir/__/libs/imageproperties/imagepropertiessidebarcamgui.o CMakeFiles/digikam.dir/__/libs/imageproperties/imagepropertiessidebardb.o CMakeFiles/digikam.dir/__/libs/imageproperties/cameraitempropertiestab.o CMakeFiles/digikam.dir/__/libs/imageproperties/imagedescedittab.o CMakeFiles/digikam.dir/__/libs/imageproperties/captionedit.o CMakeFiles/digikam.dir/__/utilities/setup/setupicc.o CMakeFiles/digikam.dir/__/utilities/setup/setupcollections.o CMakeFiles/digikam.dir/__/utilities/setup/setupcollectionview.o CMakeFiles/digikam.dir/__/utilities/setup/setupcategory.o CMakeFiles/digikam.dir/__/utilities/setup/setupalbumview.o CMakeFiles/digikam.dir/__/utilities/setup/setup.o CMakeFiles/digikam.dir/__/utilities/setup/setuptooltip.o CMakeFiles/digikam.dir/__/utilities/setup/setuptemplate.o CMakeFiles/digikam.dir/__/utilities/setup/setupmime.o CMakeFiles/digikam.dir/__/utilities/setup/setupslideshow.o CMakeFiles/digikam.dir/__/utilities/setup/setupmetadata.o CMakeFiles/digikam.dir/__/utilities/setup/setupeditor.o CMakeFiles/digikam.dir/__/utilities/setup/setupmisc.o CMakeFiles/digikam.dir/__/utilities/setup/setuplighttable.o CMakeFiles/digikam.dir/__/utilities/setup/setupiofiles.o CMakeFiles/digikam.dir/__/utilities/setup/setupplugins.o CMakeFiles/digikam.dir/__/utilities/setup/setupdcraw.o CMakeFiles/digikam.dir/__/utilities/setup/setupcamera.o CMakeFiles/digikam.dir/__/utilities/setup/cameraselection.o CMakeFiles/digikam.dir/__/utilities/setup/cameralist.o CMakeFiles/digikam.dir/__/utilities/setup/cameratype.o CMakeFiles/digikam.dir/__/utilities/setup/setupdatabase.o CMakeFiles/digikam.dir/__/utilities/lighttable/lighttablepreview.o CMakeFiles/digikam.dir/__/utilities/lighttable/lighttableview.o CMakeFiles/digikam.dir/__/utilities/lighttable/lighttablebar.o CMakeFiles/digikam.dir/__/utilities/lighttable/lighttablewindow.o CMakeFiles/digikam.dir/__/utilities/batch/imageinfojob.o CMakeFiles/digikam.dir/__/utilities/batch/imageinfoalbumsjob.o CMakeFiles/digikam.dir/__/utilities/batch/batchthumbsgenerator.o CMakeFiles/digikam.dir/__/utilities/batch/batchalbumssyncmetadata.o CMakeFiles/digikam.dir/__/utilities/batch/batchsyncmetadata.o CMakeFiles/digikam.dir/__/utilities/batch/fingerprintsgenerator.o CMakeFiles/digikam.dir/__/utilities/kipiiface/kipiimageinfo.o CMakeFiles/digikam.dir/__/utilities/kipiiface/kipiimagecollection.o CMakeFiles/digikam.dir/__/utilities/kipiiface/kipiimagecollectionselector.o CMakeFiles/digikam.dir/__/utilities/kipiiface/kipiuploadwidget.o CMakeFiles/digikam.dir/__/utilities/kipiiface/kipiinterface.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchwindow.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchview.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchgroup.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchfieldgroup.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchfields.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchutilities.o CMakeFiles/digikam.dir/__/utilities/searchwindow/ratingsearchutilities.o CMakeFiles/digikam.dir/__/utilities/searchwindow/choicesearchutilities.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchfolderview.o CMakeFiles/digikam.dir/__/utilities/searchwindow/searchtabheader.o CMakeFiles/digikam.dir/__/utilities/fuzzysearch/fuzzysearchview.o CMakeFiles/digikam.dir/__/utilities/fuzzysearch/findduplicatesview.o CMakeFiles/digikam.dir/__/utilities/fuzzysearch/findduplicatesalbumitem.o CMakeFiles/digikam.dir/__/utilities/fuzzysearch/sketchwidget.o CMakeFiles/digikam.dir/__/utilities/gpssearch/gpssearchview.o CMakeFiles/digikam.dir/__/utilities/gpssearch/gpssearchwidget.o CMakeFiles/digikam.dir/__/utilities/timeline/timelinewidget.o CMakeFiles/digikam.dir/__/libs/models/imagealbummodel.o CMakeFiles/digikam.dir/__/libs/models/imagealbumfiltermodel.o CMakeFiles/digikam.dir/__/libs/models/abstractalbummodel.o CMakeFiles/digikam.dir/__/libs/models/albummodel.o CMakeFiles/digikam.dir/__/libs/models/albumfiltermodel.o CMakeFiles/digikam.dir/__/libs/models/albummodeldragdrophandler.o CMakeFiles/digikam.dir/addtagslineedit.o CMakeFiles/digikam.dir/album.o CMakeFiles/digikam.dir/albumdragdrop.o CMakeFiles/digikam.dir/albumhistory.o CMakeFiles/digikam.dir/albumiconviewfilter.o CMakeFiles/digikam.dir/albummanager.o CMakeFiles/digikam.dir/albummodificationhelper.o CMakeFiles/digikam.dir/albumpropsedit.o CMakeFiles/digikam.dir/albumselectcombobox.o CMakeFiles/digikam.dir/albumselectdialog.o CMakeFiles/digikam.dir/albumselectiontreeview.o CMakeFiles/digikam.dir/albumselectwidget.o CMakeFiles/digikam.dir/albumsettings.o CMakeFiles/digikam.dir/albumthumbnailloader.o CMakeFiles/digikam.dir/albumtreeview.o CMakeFiles/digikam.dir/albumwidgetstack.o CMakeFiles/digikam.dir/contextmenuhelper.o CMakeFiles/digikam.dir/datefolderview.o CMakeFiles/digikam.dir/dbstatdlg.o CMakeFiles/digikam.dir/ddragobjects.o CMakeFiles/digikam.dir/digikamapp.o CMakeFiles/digikam.dir/digikamimageview.o CMakeFiles/digikam.dir/digikamimageview_p.o CMakeFiles/digikam.dir/digikamimagedelegate.o CMakeFiles/digikam.dir/digikammodelcollection.o CMakeFiles/digikam.dir/digikamview.o CMakeFiles/digikam.dir/dio.o CMakeFiles/digikam.dir/editablesearchtreeview.o CMakeFiles/digikam.dir/icongroupitem.o CMakeFiles/digikam.dir/iconitem.o CMakeFiles/digikam.dir/iconview.o CMakeFiles/digikam.dir/imageattributeswatch.o CMakeFiles/digikam.dir/imagecategorizedview.o CMakeFiles/digikam.dir/imagecategorydrawer.o CMakeFiles/digikam.dir/imagedelegate.o CMakeFiles/digikam.dir/imagedragdrop.o CMakeFiles/digikam.dir/imagepreviewbar.o CMakeFiles/digikam.dir/imagepreviewview.o CMakeFiles/digikam.dir/imageratingoverlay.o CMakeFiles/digikam.dir/imagerotationoverlay.o CMakeFiles/digikam.dir/imagethumbnailbar.o CMakeFiles/digikam.dir/imagethumbnaildelegate.o CMakeFiles/digikam.dir/imageselectionoverlay.o CMakeFiles/digikam.dir/imageviewutilities.o CMakeFiles/digikam.dir/kdateedit.o CMakeFiles/digikam.dir/kdatepickerpopup.o CMakeFiles/digikam.dir/kdatetimeedit.o CMakeFiles/digikam.dir/leftsidebarwidgets.o CMakeFiles/digikam.dir/mediaplayerview.o CMakeFiles/digikam.dir/metadatahub.o CMakeFiles/digikam.dir/metadatamanager.o CMakeFiles/digikam.dir/mimefilter.o CMakeFiles/digikam.dir/monthwidget.o CMakeFiles/digikam.dir/ratingfilter.o CMakeFiles/digikam.dir/ratingpopupmenu.o CMakeFiles/digikam.dir/scancontroller.o CMakeFiles/digikam.dir/sidebarwidget.o CMakeFiles/digikam.dir/syncjob.o CMakeFiles/digikam.dir/tagcheckview.o CMakeFiles/digikam.dir/tagdragdrop.o CMakeFiles/digikam.dir/tageditdlg.o CMakeFiles/digikam.dir/tagfiltersidebarwidget.o CMakeFiles/digikam.dir/tagfolderview.o CMakeFiles/digikam.dir/tagmodificationhelper.o CMakeFiles/digikam.dir/tagspopupmenu.o CMakeFiles/digikam.dir/tooltipfiller.o CMakeFiles/digikam.dir/searchmodificationhelper.o CMakeFiles/digikam.dir/welcomepageview.o CMakeFiles/digikam.dir/databaseguierrorhandler.o CMakeFiles/digikam.dir/__/utilities/firstrun/assistantdlg.o CMakeFiles/digikam.dir/__/utilities/firstrun/assistantdlgpage.o CMakeFiles/digikam.dir/__/utilities/firstrun/welcomepage.o CMakeFiles/digikam.dir/__/utilities/firstrun/collectionpage.o CMakeFiles/digikam.dir/__/utilities/firstrun/rawpage.o CMakeFiles/digikam.dir/__/utilities/firstrun/tooltipspage.o CMakeFiles/digikam.dir/__/utilities/firstrun/previewpage.o CMakeFiles/digikam.dir/__/utilities/firstrun/openfilepage.o CMakeFiles/digikam.dir/__/utilities/firstrun/metadatapage.o CMakeFiles/digikam.dir/__/utilities/firstrun/startscanpage.o CMakeFiles/digikam.dir/__/libs/template/templatemanager.o CMakeFiles/digikam.dir/__/libs/template/templatelist.o CMakeFiles/digikam.dir/__/libs/template/templateselector.o CMakeFiles/digikam.dir/__/libs/template/templateviewer.o CMakeFiles/digikam.dir/__/libs/template/templatepanel.o CMakeFiles/digikam.dir/__/libs/template/subjectedit.o CMakeFiles/digikam.dir/__/libs/widgets/common/databasewidget.o CMakeFiles/digikam.dir/__/libs/dialogs/migrationdlg.o CMakeFiles/digikam.dir/main.o CMakeFiles/digikam.dir/digikamadaptor.o -o digikam -rdynamic -L/home/users/arekm/rpm/BUILD/digikam-1.6.0/build/lib /usr/lib64/libkparts.so.4.5.0 -lphonon /usr/lib64/libkhtml.so.5.5.0 /usr/lib64/libkutils.so.4.5.0 /usr/lib64/libknotifyconfig.so.4.5.0 /usr/lib64/libsolid.so.4.5.0 -lkipi -lkexiv2 -lkdcraw /usr/lib64/libQtSql.so /usr/lib64/libQt3Support.so -llcms -L/usr/lib64 -lgphoto2_port -L/usr/lib64 -lgphoto2 -lgphoto2_port -lm ../lib/libdigikamcore.so.1.0.0 ../lib/libdigikamdatabase.so.1.0.0 ../lib/libadvancedrename.a ../lib/libqueuemanager.a ../lib/libcameragui.a /usr/lib64/libkabc.so.4.5.0 -lmarblewidget -lkexiv2 -lkdcraw ../lib/libdigikamdatabase.so.1.0.0 ../lib/libdigikamcore.so.1.0.0 /usr/lib64/libkhtml.so.5.5.0 /usr/lib64/libkjs.so.4.5.0 /usr/lib64/libkutils.so.4.5.0 /usr/lib64/libkemoticons.so.4.5.0 /usr/lib64/libkidletime.so.4.5.0 /usr/lib64/libkcmutils.so.4.5.0 /usr/lib64/libkprintutils.so.4.5.0 /usr/lib64/libkparts.so.4.5.0 /usr/lib64/libknotifyconfig.so.4.5.0 /usr/lib64/libkresources.so.4.5.0 /usr/lib64/libkio.so.5.5.0 /usr/lib64/libsolid.so.4.5.0 /usr/lib64/libnepomuk.so.4.5.0 /usr/lib64/libkdeui.so.5.5.0 /usr/lib64/libQtGui.so /usr/lib64/libQtSvg.so /usr/lib64/libkdecore.so.5.5.0 /usr/lib64/libQtCore.so -lpthread /usr/lib64/libQtDBus.so -lsoprano /usr/lib64/libQtNetwork.so /usr/lib64/libQtXml.so -Wl,-rpath,/home/users/arekm/rpm/BUILD/digikam-1.6.0/build/lib:
/usr/bin/ld: /usr/lib64/libgphoto2.so: undefined reference to symbol 'gp_port_free'
/usr/bin/ld: note: 'gp_port_free' is defined in DSO /usr/lib64/libgphoto2_port.so so try adding it to the linker command line
/usr/lib64/libgphoto2_port.so: could not read symbols: Invalid operation
collect2: ld returned 1 exit status
make[2]: *** [digikam/digikam] Error 1