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/aty/aty128fb.c b/drivers/video/aty/aty128fb.c
index 8726c3669713..e86d7e0c9825 100644
--- a/drivers/video/aty/aty128fb.c
+++ b/drivers/video/aty/aty128fb.c
@@ -357,6 +357,12 @@ static int default_lcd_on __devinitdata = 1;
 static int mtrr = 1;
 #endif
 
+#ifdef CONFIG_PMAC_BACKLIGHT
+static int backlight __devinitdata = 1;
+#else
+static int backlight __devinitdata = 0;
+#endif
+
 /* PLL constants */
 struct aty128_constants {
         u32 ref_clk;
@@ -1652,6 +1658,9 @@ static int __devinit aty128fb_setup(char *options)
                 } else if (!strncmp(this_opt, "crt:", 4)) {
                         default_crt_on = simple_strtoul(this_opt+4, NULL, 0);
                         continue;
+                } else if (!strncmp(this_opt, "backlight:", 10)) {
+                        backlight = simple_strtoul(this_opt+10, NULL, 0);
+                        continue;
                 }
 #ifdef CONFIG_MTRR
                 if(!strncmp(this_opt, "nomtrr", 6)) {
@@ -1985,7 +1994,8 @@ static int __devinit aty128_init(struct pci_dev *pdev, const struct pci_device_i
         par->lock_blank = 0;
 
 #ifdef CONFIG_FB_ATY128_BACKLIGHT
-        aty128_bl_init(par);
+        if (backlight)
+                aty128_bl_init(par);
 #endif
 
         if (register_framebuffer(info) < 0)