backlight: Allow enable/disable of fb backlights, fixing regressions

Enabling the backlight by default appears to cause problems for many
users. This patch disables backlight controls unless explicitly
enabled by users via a module parameter. Since PMAC users are known
to work, default to enabled in that case.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>

1 files changed, 11 insertions, 1 deletions

diff --git a/drivers/video/nvidia/nvidia.c b/drivers/video/nvidia/nvidia.c
index c18e9557ca30..b97ec6901263 100644
--- a/drivers/video/nvidia/nvidia.c
+++ b/drivers/video/nvidia/nvidia.c
@@ -83,6 +83,11 @@ static int bpp __devinitdata = 8;
 #ifdef CONFIG_MTRR
 static int nomtrr __devinitdata = 0;
 #endif
+#ifdef CONFIG_PMAC_BACKLIGHT
+static int backlight __devinitdata = 1;
+#else
+static int backlight __devinitdata = 0;
+#endif
 
 static char *mode_option __devinitdata = NULL;
 
@@ -1311,7 +1316,10 @@ static int __devinit nvidiafb_probe(struct pci_dev *pd,
         nvidia_save_vga(par, &par->SavedReg);
 
         pci_set_drvdata(pd, info);
-        nvidia_bl_init(par);
+
+        if (backlight)
+                nvidia_bl_init(par);
+
         if (register_framebuffer(info) < 0) {
                 printk(KERN_ERR PFX "error registering nVidia framebuffer\n");
                 goto err_out_iounmap_fb;
@@ -1408,6 +1416,8 @@ static int __devinit nvidiafb_setup(char *options)
                         paneltweak = simple_strtoul(this_opt+11, NULL, 0);
                 } else if (!strncmp(this_opt, "vram:", 5)) {
                         vram = simple_strtoul(this_opt+5, NULL, 0);
+                } else if (!strncmp(this_opt, "backlight:", 10)) {
+                        backlight = simple_strtoul(this_opt+10, NULL, 0);
 #ifdef CONFIG_MTRR
                 } else if (!strncmp(this_opt, "nomtrr", 6)) {
                         nomtrr = 1;