1 files changed, 7 insertions, 5 deletions

diff --git a/drivers/video/nvidia/nv_setup.c b/drivers/video/nvidia/nv_setup.c
index 707e2c8a13ed..82579d3a9970 100644
--- a/drivers/video/nvidia/nv_setup.c
+++ b/drivers/video/nvidia/nv_setup.c
@@ -166,11 +166,13 @@ u8 NVReadDacData(struct nvidia_par *par)
 static int NVIsConnected(struct nvidia_par *par, int output)
 {
         volatile u32 __iomem *PRAMDAC = par->PRAMDAC0;
-        u32 reg52C, reg608;
+        u32 reg52C, reg608, dac0_reg608 = 0;
         int present;
 
-        if (output)
-                PRAMDAC += 0x800;
+        if (output) {
+            dac0_reg608 = NV_RD32(PRAMDAC, 0x0608);
+            PRAMDAC += 0x800;
+        }
 
         reg52C = NV_RD32(PRAMDAC, 0x052C);
         reg608 = NV_RD32(PRAMDAC, 0x0608);
@@ -194,8 +196,8 @@ static int NVIsConnected(struct nvidia_par *par, int output)
         else
                 printk("nvidiafb: CRTC%i analog not found\n", output);
 
-        NV_WR32(par->PRAMDAC0, 0x0608, NV_RD32(par->PRAMDAC0, 0x0608) &
-                0x0000EFFF);
+        if (output)
+            NV_WR32(par->PRAMDAC0, 0x0608, dac0_reg608);
 
         NV_WR32(PRAMDAC, 0x052C, reg52C);
         NV_WR32(PRAMDAC, 0x0608, reg608);