[PATCH] fbdev: statically link the framebuffer notification functions

The backlight and lcd subsystems can be notified by the framebuffer layer
of blanking events. However, these subsystems, as a whole, can function
independently from the framebuffer layer. But in order to enable to the
lcd and backlight subsystems, the framebuffer has to be compiled also,
effectively sucking in a huge amount of unneeded code.

To prevent dependency problems, separate out the framebuffer notification
mechanism from the framebuffer layer and permanently link it to the kernel.

Signed-off-by: Antonino Daplas <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/video/Kconfig

···
 	source "drivers/video/logo/Kconfig"
 endif
 
-if FB && SYSFS
+if SYSFS
 	source "drivers/video/backlight/Kconfig"
 endif
 

drivers/video/Makefile

···
 
 # Each configuration option enables a list of files.
 
+obj-y                             += fb_notify.o
 obj-$(CONFIG_FB)                  += fb.o
 fb-y                              := fbmem.o fbmon.o fbcmap.o fbsysfs.o \
                                      modedb.o fbcvt.o

drivers/video/backlight/Kconfig

···
 
 config BACKLIGHT_CLASS_DEVICE
         tristate "Lowlevel Backlight controls"
-	depends on BACKLIGHT_LCD_SUPPORT && FB
+	depends on BACKLIGHT_LCD_SUPPORT
 	default m
 	help
 	  This framework adds support for low-level control of the LCD
···
 
 config LCD_CLASS_DEVICE
         tristate "Lowlevel LCD controls"
-	depends on BACKLIGHT_LCD_SUPPORT && FB
+	depends on BACKLIGHT_LCD_SUPPORT
 	default m
 	help
 	  This framework adds support for low-level control of LCD.

drivers/video/fb_notify.c

···
+/*
+ *  linux/drivers/video/fb_notify.c
+ *
+ *  Copyright (C) 2006 Antonino Daplas <[e-mail]>
+ *
+ *	2001 - Documented with DocBook
+ *	- Brad Douglas <[e-mail]>
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file COPYING in the main directory of this archive
+ * for more details.
+ */
+#include <linux/fb.h>
+#include <linux/notifier.h>
+
+static BLOCKING_NOTIFIER_HEAD(fb_notifier_list);
+
+/**
+ *	fb_register_client - register a client notifier
+ *	@nb: notifier block to callback on events
+ */
+int fb_register_client(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_register(&fb_notifier_list, nb);
+}
+EXPORT_SYMBOL(fb_register_client);
+
+/**
+ *	fb_unregister_client - unregister a client notifier
+ *	@nb: notifier block to callback on events
+ */
+int fb_unregister_client(struct notifier_block *nb)
+{
+	return blocking_notifier_chain_unregister(&fb_notifier_list, nb);
+}
+EXPORT_SYMBOL(fb_unregister_client);
+
+/**
+ * fb_notifier_call_chain - notify clients of fb_events
+ *
+ */
+int fb_notifier_call_chain(unsigned long val, void *v)
+{
+	return blocking_notifier_call_chain(&fb_notifier_list, val, v);
+}
+EXPORT_SYMBOL_GPL(fb_notifier_call_chain);

drivers/video/fbmem.c

···
 
 #define FBPIXMAPSIZE	(1024 * 8)
 
-static BLOCKING_NOTIFIER_HEAD(fb_notifier_list);
 struct fb_info *registered_fb[FB_MAX];
 int num_registered_fb;
 
···
 
 		    event.info = info;
 		    event.data = &mode1;
-		    ret = blocking_notifier_call_chain(&fb_notifier_list,
-					      FB_EVENT_MODE_DELETE, &event);
+		    ret = fb_notifier_call_chain(FB_EVENT_MODE_DELETE, &event);
 		}
 
 		if (!ret)
···
 
 				info->flags &= ~FBINFO_MISC_USEREVENT;
 				event.info = info;
-				blocking_notifier_call_chain(&fb_notifier_list,
-						evnt, &event);
+				fb_notifier_call_chain(evnt, &event);
 			}
 		}
 	}
···
 
 		event.info = info;
 		event.data = ␣
-		blocking_notifier_call_chain(&fb_notifier_list,
-				FB_EVENT_BLANK, &event);
+		fb_notifier_call_chain(FB_EVENT_BLANK, &event);
 	}
 
  	return ret;
···
 		con2fb.framebuffer = -1;
 		event.info = info;
 		event.data = &con2fb;
-		blocking_notifier_call_chain(&fb_notifier_list,
-				    FB_EVENT_GET_CONSOLE_MAP, &event);
+		fb_notifier_call_chain(FB_EVENT_GET_CONSOLE_MAP, &event);
 		return copy_to_user(argp, &con2fb,
 				    sizeof(con2fb)) ? -EFAULT : 0;
 	case FBIOPUT_CON2FBMAP:
···
 		    return -EINVAL;
 		event.info = info;
 		event.data = &con2fb;
-		return blocking_notifier_call_chain(&fb_notifier_list,
-					   FB_EVENT_SET_CONSOLE_MAP,
-					   &event);
+		return fb_notifier_call_chain(FB_EVENT_SET_CONSOLE_MAP,
+					      &event);
 	case FBIOBLANK:
 		acquire_console_sem();
 		info->flags |= FBINFO_MISC_USEREVENT;
···
 	registered_fb[i] = fb_info;
 
 	event.info = fb_info;
-	blocking_notifier_call_chain(&fb_notifier_list,
-			    FB_EVENT_FB_REGISTERED, &event);
+	fb_notifier_call_chain(FB_EVENT_FB_REGISTERED, &event);
 	return 0;
 }
 
···
 	fb_cleanup_class_device(fb_info);
 	class_device_destroy(fb_class, MKDEV(FB_MAJOR, i));
 	event.info = fb_info;
-	blocking_notifier_call_chain(&fb_notifier_list,
-				     FB_EVENT_FB_UNREGISTERED, &event);
+	fb_notifier_call_chain(FB_EVENT_FB_UNREGISTERED, &event);
 	return 0;
-}
-
-/**
- *	fb_register_client - register a client notifier
- *	@nb: notifier block to callback on events
- */
-int fb_register_client(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_register(&fb_notifier_list, nb);
-}
-
-/**
- *	fb_unregister_client - unregister a client notifier
- *	@nb: notifier block to callback on events
- */
-int fb_unregister_client(struct notifier_block *nb)
-{
-	return blocking_notifier_chain_unregister(&fb_notifier_list, nb);
 }
 
 /**
···
 
 	event.info = info;
 	if (state) {
-		blocking_notifier_call_chain(&fb_notifier_list,
-				FB_EVENT_SUSPEND, &event);
+		fb_notifier_call_chain(FB_EVENT_SUSPEND, &event);
 		info->state = FBINFO_STATE_SUSPENDED;
 	} else {
 		info->state = FBINFO_STATE_RUNNING;
-		blocking_notifier_call_chain(&fb_notifier_list,
-				FB_EVENT_RESUME, &event);
+		fb_notifier_call_chain(FB_EVENT_RESUME, &event);
 	}
 }
 
···
 
 	if (!list_empty(&info->modelist)) {
 		event.info = info;
-		err = blocking_notifier_call_chain(&fb_notifier_list,
-					   FB_EVENT_NEW_MODELIST,
-					   &event);
+		err = fb_notifier_call_chain(FB_EVENT_NEW_MODELIST, &event);
 	}
 
 	return err;
···
 EXPORT_SYMBOL(fb_pan_display);
 EXPORT_SYMBOL(fb_get_buffer_offset);
 EXPORT_SYMBOL(fb_set_suspend);
-EXPORT_SYMBOL(fb_register_client);
-EXPORT_SYMBOL(fb_unregister_client);
 EXPORT_SYMBOL(fb_get_options);
 
 MODULE_LICENSE("GPL");

include/linux/fb.h

···
 
 extern int fb_register_client(struct notifier_block *nb);
 extern int fb_unregister_client(struct notifier_block *nb);
-
+extern int fb_notifier_call_chain(unsigned long val, void *v);
 /*
  * Pixmap structure definition
  *