intelfb: add vsync interrupt support

[03/05] intelfb: Implement basic interrupt handling

Functions have been added to enable and disable interrupts using the MMIO registers. Currently only pipe A vsync interrupts are enabled.
A generalized vsync accounting struct is defined, with the intent that it can encapsulate per-pipe vsync related info in the future. Currently a single instance is hard-coded.
The interrupt service routine currently only looks for vsync interrupts on pipe A, and increments a counter and wakes up anyone waiting on it.

This implementation is heavily influenced by similar implementations in the atyfb and matroxfb drivers.

Signed-off-by: Eric Hustvedt <ehustvedt@cecropia.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/video/intelfb/intelfbhw.h b/drivers/video/intelfb/intelfbhw.h
index 8d2e36972fc8..aa0c139a2301 100644
--- a/drivers/video/intelfb/intelfbhw.h
+++ b/drivers/video/intelfb/intelfbhw.h
@@ -561,5 +561,7 @@ extern void intelfbhw_cursor_setcolor(struct intelfb_info *dinfo, u32 bg,
 extern void intelfbhw_cursor_load(struct intelfb_info *dinfo, int width,
                                   int height, u8 *data);
 extern void intelfbhw_cursor_reset(struct intelfb_info *dinfo);
+extern int intelfbhw_enable_irq(struct intelfb_info *dinfo, int reenable);
+extern void intelfbhw_disable_irq(struct intelfb_info *dinfo);
 
 #endif /* _INTELFBHW_H */