omaplcd_linux.c:
irqreturn_t vsync_isr(int irq, void *dev_id, struct pt_regs *regs)
should be
static irqreturn_t vsync_isr(int irq, void *dev_id)
Also in mmap.c
function define as PKV_OFFSET_STRUCT *PVRMMapRegisterArea
but return PKV_OFFSET_STRUCT