Detaching fbcon: Add capability to attach/detach fbcon

index a8de822..b910eff 100644
@@ -194,7 +194,8 @@ static void fbcon_redraw_move(struct vc_
 			      int line, int count, int dy);
 static void fbcon_modechanged(struct fb_info *info);
 static void fbcon_set_all_vcs(struct fb_info *info);
-
+static void fbcon_start(void);
+static void fbcon_exit(void);
 static struct class_device *fbcon_class_device;
 
 #ifdef CONFIG_MAC

@@ -391,15 +392,18 @@ static void fb_flashcursor(void *private
 	int c;
 	int mode;
 
-	if (ops->currcon != -1)
+	acquire_console_sem();
+	if (ops && ops->currcon != -1)
 		vc = vc_cons[ops->currcon].d;
 
 	if (!vc || !CON_IS_VISIBLE(vc) ||
 	    fbcon_is_inactive(vc, info) ||
  	    registered_fb[con2fb_map[vc->vc_num]] != info ||
-	    vc_cons[ops->currcon].d->vc_deccm != 1)
+	    vc_cons[ops->currcon].d->vc_deccm != 1) {
+		release_console_sem();
 		return;
-	acquire_console_sem();
+	}
+
 	p = &fb_display[vc->vc_num];
 	c = scr_readw((u16 *) vc->vc_pos);
 	mode = (!ops->cursor_flash || ops->cursor_state.enable) ?

@@ -2101,12 +2105,11 @@ static int fbcon_switch(struct vc_data *
 		if (info->fbops->fb_set_par)
 			info->fbops->fb_set_par(info);
 
-		if (old_info != info) {
+		if (old_info != info)
 			fbcon_del_cursor_timer(old_info);
-			fbcon_add_cursor_timer(info);
-		}
 	}
 
+	fbcon_add_cursor_timer(info);
 	set_blitting_type(vc, info);
 	ops->cursor_reset = 1;
 

@@ -2847,7 +2850,8 @@ static int fbcon_fb_registered(int idx)
 			ret = fbcon_takeover(1);
 	} else {
 		for (i = 0; i < MAX_NR_CONSOLES; i++) {
-			if (con2fb_map_boot[i] == idx)
+			if (con2fb_map_boot[i] == idx &&
+			    con2fb_map[i] == -1)
 				set_con2fb_map(i, idx, 0);
 		}
 	}

@@ -3046,9 +3050,32 @@ err:
 	return snprintf(buf, PAGE_SIZE, "%d\n", rotate);
 }
 
+static ssize_t store_attach(struct class_device *class_device,
+			    const char *buf, size_t count)
+{
+	if (info_idx == -1)
+		fbcon_start();
+
+	return count;
+}
+
+static ssize_t store_detach(struct class_device *class_device,
+			    const char *buf, size_t count)
+{
+	if (info_idx != -1) {
+		fbcon_exit();
+		give_up_console(&fb_con);
+	}
+
+	info_idx = -1;
+	return count;
+}
+
 static struct class_device_attribute class_device_attrs[] = {
 	__ATTR(rotate, S_IRUGO|S_IWUSR, show_rotate, store_rotate),
 	__ATTR(rotate_all, S_IWUSR, NULL, store_rotate_all),
+	__ATTR(attach, S_IWUSR, NULL, store_attach),
+	__ATTR(detach, S_IWUSR, NULL, store_detach),
 };
 
 static int fbcon_init_class_device(void)

@@ -3061,67 +3088,31 @@ static int fbcon_init_class_device(void)
 	return 0;
 }
 
-static int __init fb_console_init(void)
+static void fbcon_start(void)
 {
-	int i;
-
-	acquire_console_sem();
-	fb_register_client(&fbcon_event_notifier);
-	release_console_sem();
-
-	fbcon_class_device =
-	    class_device_create(fb_class, NULL,
-				MKDEV(FB_MAJOR, FB_MAX), NULL,
-				"fbcon");
-	if (IS_ERR(fbcon_class_device)) {
-	    printk(KERN_WARNING "Unable to create class_device "
-		   "for fbcon; errno = %ld\n",
-		   PTR_ERR(fbcon_class_device));
-	    fbcon_class_device = NULL;
-	} else
-	    fbcon_init_class_device();
+	if (num_registered_fb) {
+		int i;
 
-	for (i = 0; i < MAX_NR_CONSOLES; i++)
-		con2fb_map[i] = -1;
+		acquire_console_sem();
 
-	if (num_registered_fb) {
 		for (i = 0; i < FB_MAX; i++) {
 			if (registered_fb[i] != NULL) {
 				info_idx = i;
 				break;
 			}
 		}
+
+		release_console_sem();
 		fbcon_takeover(0);
 	}
-
-	return 0;
-}
-
-module_init(fb_console_init);
-
-#ifdef MODULE
-
-static void __exit fbcon_deinit_class_device(void)
-{
-	int i;
-
-	for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++)
-		class_device_remove_file(fbcon_class_device,
-					 &class_device_attrs[i]);
 }
 
-static void __exit fbcon_exit(void)
+static void fbcon_exit(void)
 {
 	struct fb_info *info;
 	int i, j, mapped;
 
-	for (i = 0; i < FB_MAX; i++) {
-		info = registered_fb[i];
-
-		if (info && info->fbcon_par)
-			fbcon_del_cursor_timer(info);
-	}
-
+	acquire_console_sem();
 #ifdef CONFIG_ATARI
 	free_irq(IRQ_AUTO_4, fbcon_vbl_handler);
 #endif

@@ -3131,6 +3122,7 @@ #ifdef CONFIG_MAC
 #endif
 
 	kfree((void *)softback_buf);
+	softback_buf = 0UL;
 
 	for (i = 0; i < FB_MAX; i++) {
 		mapped = 0;

@@ -3150,22 +3142,69 @@ #endif
 			if (info->fbops->fb_release)
 				info->fbops->fb_release(info, 0);
 			module_put(info->fbops->owner);
-			kfree(info->fbcon_par);
-			info->fbcon_par = NULL;
+
+			if (info->fbcon_par) {
+				fbcon_del_cursor_timer(info);
+				kfree(info->fbcon_par);
+				info->fbcon_par = NULL;
+			}
+
+			if (info->queue.func == fb_flashcursor)
+				info->queue.func = NULL;
+
 		}
 	}
 
-	fbcon_deinit_class_device();
-	class_device_destroy(fb_class, MKDEV(FB_MAJOR, FB_MAX));
+	release_console_sem();
+}
+
+static int __init fb_console_init(void)
+{
+	int i;
+
+	acquire_console_sem();
+	fb_register_client(&fbcon_event_notifier);
+	fbcon_class_device =
+	    class_device_create(fb_class, NULL,
+				MKDEV(FB_MAJOR, FB_MAX), NULL,
+				"fbcon");
+
+	if (IS_ERR(fbcon_class_device)) {
+		printk(KERN_WARNING "Unable to create class_device "
+		       "for fbcon; errno = %ld\n",
+		       PTR_ERR(fbcon_class_device));
+		fbcon_class_device = NULL;
+	} else
+		fbcon_init_class_device();
+
+	for (i = 0; i < MAX_NR_CONSOLES; i++)
+		con2fb_map[i] = -1;
+
+	release_console_sem();
+	fbcon_start();
+	return 0;
+}
+
+module_init(fb_console_init);
+
+#ifdef MODULE
+
+static void fbcon_deinit_class_device(void)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(class_device_attrs); i++)
+		class_device_remove_file(fbcon_class_device,
+					 &class_device_attrs[i]);
 }
 
 static void __exit fb_console_exit(void)
 {
 	acquire_console_sem();
 	fb_unregister_client(&fbcon_event_notifier);
-	fbcon_exit();
+	fbcon_deinit_class_device();
+	class_device_destroy(fb_class, MKDEV(FB_MAJOR, FB_MAX));
 	release_console_sem();
-	give_up_console(&fb_con);
 }	
 
 module_exit(fb_console_exit);