Extern or forward variable declaration at include/media/v4l2-subdev.h, line 44 References: drivers/media/i2c/adv7180.c, line 771 drivers/media/i2c/adv7604.c, line 2605 drivers/media/i2c/adv7842.c, line 3238 drivers/media/i2c/tc358743.c, line 1328 drivers/media/pci/cobalt/cobalt-v4l2.c, line 1065 drivers/media/pci/ivtv/ivtv-ioctl.c, line 1500 drivers/media/pci/solo6x10/solo6x10-v4l2-enc.c, line 1139 drivers/media/platform/coda/coda-common.c, line 898 drivers/media/platform/omap3isp/ispccdc.c, line 1856 drivers/media/platform/omap3isp/ispccdc.c, line 1869 drivers/media/platform/omap3isp/ispstat.c, line 988 drivers/media/platform/omap3isp/ispstat.c, line 1000 drivers/media/platform/omap3isp/ispstat.h, line 138 drivers/media/platform/omap3isp/ispstat.h, line 141 drivers/media/platform/rcar-vin/rcar-v4l2.c, line 476 drivers/media/platform/s5p-mfc/s5p_mfc_dec.c, line 853 drivers/media/platform/s5p-mfc/s5p_mfc_enc.c, line 1757 drivers/media/platform/vivid/vivid-vid-out.c, line 1171 drivers/media/usb/go7007/go7007-v4l2.c, line 791 drivers/media/usb/uvc/uvc_v4l2.c, line 1242 drivers/media/v4l2-core/v4l2-ctrls.c, line 3408 drivers/media/v4l2-core/v4l2-ctrls.c, line 3417 drivers/media/v4l2-core/v4l2-ioctl.c, line 839 drivers/usb/gadget/function/uvc_v4l2.c, line 234 drivers/usb/gadget/function/uvc_v4l2.c, line 244 include/media/v4l2-subdev.h, line 44 include/media/v4l2-subdev.h, line 211 include/media/v4l2-subdev.h, line 213