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/riva/fbdev.c b/drivers/video/riva/fbdev.c
index f8a3d608b208..1d1c7c624d7f 100644
--- a/drivers/video/riva/fbdev.c
+++ b/drivers/video/riva/fbdev.c
@@ -215,6 +215,11 @@ static int noaccel   __devinitdata = 0;
 #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;
 static int  strictmode       = 0;
@@ -2059,7 +2064,10 @@ static int __devinit rivafb_probe(struct pci_dev *pd,
         info->monspecs.modedb = NULL;
 
         pci_set_drvdata(pd, info);
-        riva_bl_init(info->par);
+
+        if (backlight)
+                riva_bl_init(info->par);
+
         ret = register_framebuffer(info);
         if (ret < 0) {
                 printk(KERN_ERR PFX
@@ -2157,6 +2165,8 @@ static int __init rivafb_setup(char *options)
                                 forceCRTC = -1;
                 } else if (!strncmp(this_opt, "flatpanel", 9)) {
                         flatpanel = 1;
+                } 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;