diff options
| -rw-r--r-- | Documentation/fb/udlfb.txt | 24 | ||||
| -rw-r--r-- | drivers/video/udlfb.c | 4 |
2 files changed, 18 insertions, 10 deletions
diff --git a/Documentation/fb/udlfb.txt b/Documentation/fb/udlfb.txt index 473ceed9e4eb..c6d90a6fb901 100644 --- a/Documentation/fb/udlfb.txt +++ b/Documentation/fb/udlfb.txt @@ -87,20 +87,28 @@ Special configuration for udlfb is usually unnecessary. There are a few options, however. From the command line, pass options to modprobe -modprobe udlfb defio=1 console=1 +modprobe udlfb fb_defio=0 console=1 shadow=1 -Or for permanent option, create file like /etc/modprobe.d/options with text -options 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. -Accepted options: +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: 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, may be able to work with this enabled. - Disabled by default because of overhead and other issues. + 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. -console Allow fbcon to attach to udlfb provided framebuffers. This +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. diff --git a/drivers/video/udlfb.c b/drivers/video/udlfb.c index 2341b275e815..2b694e1c73cb 100644 --- a/drivers/video/udlfb.c +++ b/drivers/video/udlfb.c @@ -61,7 +61,7 @@ MODULE_DEVICE_TABLE(usb, id_table); /* module options */ static int console; /* Optionally allow fbcon to consume first framebuffer */ -static int fb_defio; /* Optionally enable experimental fb_defio mmap support */ +static int fb_defio = 1; /* Detect mmap writes using page faults */ static int shadow = 1; /* Optionally disable shadow framebuffer */ /* dlfb keeps a list of urbs for efficient bulk transfers */ @@ -1951,7 +1951,7 @@ module_param(console, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); MODULE_PARM_DESC(console, "Allow fbcon to consume first framebuffer found"); module_param(fb_defio, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); -MODULE_PARM_DESC(fb_defio, "Enable fb_defio mmap support. *Experimental*"); +MODULE_PARM_DESC(fb_defio, "Page fault detection of mmap writes"); module_param(shadow, bool, S_IWUSR | S_IRUSR | S_IWGRP | S_IRGRP); MODULE_PARM_DESC(shadow, "Shadow vid mem. Disable to save mem but lose perf"); |