3 files changed, 19 insertions, 1 deletions

diff --git a/drivers/video/intelfb/intelfb.h b/drivers/video/intelfb/intelfb.h
index 65ac37071a02..abd4c5632e38 100644
--- a/drivers/video/intelfb/intelfb.h
+++ b/drivers/video/intelfb/intelfb.h
@@ -211,6 +211,8 @@ struct intelfb_heap_data {
 struct intelfb_vsync {
         wait_queue_head_t wait;
         unsigned int count;
+        int pan_display;
+        u32 pan_offset;
 };
 
 struct intelfb_info {
diff --git a/drivers/video/intelfb/intelfbdrv.c b/drivers/video/intelfb/intelfbdrv.c
index 08f8241bb92a..9e93f820a939 100644
--- a/drivers/video/intelfb/intelfbdrv.c
+++ b/drivers/video/intelfb/intelfbdrv.c
@@ -900,6 +900,8 @@ intelfb_pci_register(struct pci_dev *pdev, const struct pci_device_id *ent)
         init_waitqueue_head(&dinfo->vsync.wait);
         spin_lock_init(&dinfo->int_lock);
         dinfo->irq_flags = 0;
+        dinfo->vsync.pan_display = 0;
+        dinfo->vsync.pan_offset = 0;
 
         return 0;
 
diff --git a/drivers/video/intelfb/intelfbhw.c b/drivers/video/intelfb/intelfbhw.c
index 0f9631c2ad33..8038f558611d 100644
--- a/drivers/video/intelfb/intelfbhw.c
+++ b/drivers/video/intelfb/intelfbhw.c
@@ -371,7 +371,13 @@ intelfbhw_pan_display(struct fb_var_screeninfo *var, struct fb_info *info)
 
         offset += dinfo->fb.offset << 12;
 
-        OUTREG(DSPABASE, offset);
+        dinfo->vsync.pan_offset = offset;
+        if ((var->activate & FB_ACTIVATE_VBL) && !intelfbhw_enable_irq(dinfo, 0)) {
+                dinfo->vsync.pan_display = 1;
+        } else {
+                dinfo->vsync.pan_display = 0;
+                OUTREG(DSPABASE, offset);
+        }
 
         return 0;
 }
@@ -1965,6 +1971,10 @@ intelfbhw_irq(int irq, void *dev_id, struct pt_regs *fp) {
 
         if (tmp & VSYNC_PIPE_A_INTERRUPT) {
                 dinfo->vsync.count++;
+                if (dinfo->vsync.pan_display) {
+                        dinfo->vsync.pan_display = 0;
+                        OUTREG(DSPABASE, dinfo->vsync.pan_offset);
+                }
                 wake_up_interruptible(&dinfo->vsync.wait);
                 handled = 1;
         }
@@ -2007,6 +2017,10 @@ intelfbhw_disable_irq(struct intelfb_info *dinfo) {
         u16 tmp;
 
         if (test_and_clear_bit(0, &dinfo->irq_flags)) {
+                if (dinfo->vsync.pan_display) {
+                        dinfo->vsync.pan_display = 0;
+                        OUTREG(DSPABASE, dinfo->vsync.pan_offset);
+                }
                 spin_lock_irq(&dinfo->int_lock);
                 OUTREG16(HWSTAM, 0xffff);
                 OUTREG16(IMR, 0xffff);