1 files changed, 20 insertions, 4 deletions

diff --git a/drivers/video/nvidia/nvidia.c b/drivers/video/nvidia/nvidia.c
index 96d51144094a..691151e2bce3 100644
--- a/drivers/video/nvidia/nvidia.c
+++ b/drivers/video/nvidia/nvidia.c
@@ -411,6 +411,7 @@ MODULE_DEVICE_TABLE(pci, nvidiafb_pci_tbl);
 
 /* command line data, set in nvidiafb_setup() */
 static int flatpanel __devinitdata = -1;        /* Autodetect later */
+static int fpdither __devinitdata = -1;
 static int forceCRTC __devinitdata = -1;
 static int hwcur __devinitdata = 0;
 static int noaccel __devinitdata = 0;
@@ -1026,10 +1027,19 @@ static int nvidiafb_set_par(struct fb_info *info)
         NVTRACE_ENTER();
 
         NVLockUnlock(par, 1);
-        if (!par->FlatPanel || (info->var.bits_per_pixel != 24) ||
-            !par->twoHeads)
+        if (!par->FlatPanel || !par->twoHeads)
                 par->FPDither = 0;
 
+        if (par->FPDither < 0) {
+                if ((par->Chipset & 0x0ff0) == 0x0110)
+                        par->FPDither = !!(NV_RD32(par->PRAMDAC, 0x0528)
+                                           & 0x00010000);
+                else
+                        par->FPDither = !!(NV_RD32(par->PRAMDAC, 0x083C) & 1);
+                printk(KERN_INFO PFX "Flat panel dithering %s\n",
+                       par->FPDither ? "enabled" : "disabled");
+        }
+
         info->fix.visual = (info->var.bits_per_pixel == 8) ?
             FB_VISUAL_PSEUDOCOLOR : FB_VISUAL_DIRECTCOLOR;
 
@@ -1548,9 +1558,9 @@ static int __devinit nvidiafb_probe(struct pci_dev *pd,
         sprintf(nvidiafb_fix.id, "NV%x", (pd->device & 0x0ff0) >> 4);
 
         par->FlatPanel = flatpanel;
-
         if (flatpanel == 1)
                 printk(KERN_INFO PFX "flatpanel support enabled\n");
+        par->FPDither = fpdither;
 
         par->CRTCnumber = forceCRTC;
         par->FpScale = (!noscale);
@@ -1729,6 +1739,8 @@ static int __devinit nvidiafb_setup(char *options)
                 } else if (!strncmp(this_opt, "nomtrr", 6)) {
                         nomtrr = 1;
 #endif
+                } else if (!strncmp(this_opt, "fpdither:", 9)) {
+                        fpdither = simple_strtol(this_opt+9, NULL, 0);
                 } else
                         mode_option = this_opt;
         }
@@ -1775,7 +1787,11 @@ module_exit(nvidiafb_exit);
 module_param(flatpanel, int, 0);
 MODULE_PARM_DESC(flatpanel,
                  "Enables experimental flat panel support for some chipsets. "
-                 "(0 or 1=enabled) (default=0)");
+                 "(0=disabled, 1=enabled, -1=autodetect) (default=-1)");
+module_param(fpdither, int, 0);
+MODULE_PARM_DESC(fpdither,
+                 "Enables dithering of flat panel for 6 bits panels. "
+                 "(0=disabled, 1=enabled, -1=autodetect) (default=-1)");
 module_param(hwcur, int, 0);
 MODULE_PARM_DESC(hwcur,
                  "Enables hardware cursor implementation. (0 or 1=enabled) "