1 files changed, 12 insertions, 27 deletions

diff --git a/Documentation/fb/udlfb.txt b/Documentation/fb/udlfb.txt
index 57d2f2908b1..7fdde2a02a2 100644
--- a/Documentation/fb/udlfb.txt
+++ b/Documentation/fb/udlfb.txt
@@ -87,38 +87,23 @@ Special configuration for udlfb is usually unnecessary. There are a few
 options, however.
 
 From the command line, pass options to modprobe
-modprobe udlfb fb_defio=0 console=1 shadow=1
+modprobe udlfb defio=1 console=1
 
-Or modify options on the fly at /sys/module/udlfb/parameters directory via
-sudo nano fb_defio
-change the parameter in place, and save the file.
+Or for permanent option, create file like /etc/modprobe.d/options with text
+options udlfb defio=1 console=1
 
-Unplug/replug USB device to apply with new settings
-
-Or for permanent option, create file like /etc/modprobe.d/udlfb.conf with text
-options udlfb fb_defio=0 console=1 shadow=1
-
-Accepted boolean options:
+Accepted options:
 
 fb_defio        Make use of the fb_defio (CONFIG_FB_DEFERRED_IO) kernel
                 module to track changed areas of the framebuffer by page faults.
-                Standard fbdev applications that use mmap but that do not
-                report damage, should be able to work with this enabled.
-                Disable when running with X server that supports reporting
-                changed regions via ioctl, as this method is simpler,
-                more stable, and higher performance.
-                default: fb_defio=1
-
-console Allow fbcon to attach to udlfb provided framebuffers.
-                Can be disabled if fbcon and other clients
-                (e.g. X with --shared-vt) are in conflict.
-                default: console=1
-
-shadow          Allocate a 2nd framebuffer to shadow what's currently across
-                the USB bus in device memory. If any pixels are unchanged,
-                do not transmit. Spends host memory to save USB transfers.
-                Enabled by default. Only disable on very low memory systems.
-                default: shadow=1
+                Standard fbdev applications that use mmap but that do not
+                report damage, may be able to work with this enabled.
+                Disabled by default because of overhead and other issues.
+
+console         Allow fbcon to attach to udlfb provided framebuffers. This
+                is disabled by default because fbcon will aggressively consume
+                the first framebuffer it finds, which isn't usually what the
+                user wants in the case of USB displays.
 
 Sysfs Attributes
 ================