- add sysfs/udev support using "class_simple"

- please read the new documentation file "udev.txt" for a short description on how to create the proper udev rules

2 files changed, 47 insertions, 0 deletions

diff --git a/linux/Documentation/dvb/readme.txt b/linux/Documentation/dvb/readme.txt
index e38016cf8..727e30470 100644
--- a/linux/Documentation/dvb/readme.txt
+++ b/linux/Documentation/dvb/readme.txt
@@ -45,4 +45,7 @@ various bt8xx based "budget" DVB cards
 contains detailed informations about the
 Visionplus VisionDTV USB-Ter DVB-T adapter.
 
+"udev.txt"
+how to get DVB and udev up and running.
+
 Good luck and have fun!
diff --git a/linux/Documentation/dvb/udev.txt b/linux/Documentation/dvb/udev.txt
new file mode 100644
index 000000000..8ef0616ed
--- /dev/null
+++ b/linux/Documentation/dvb/udev.txt
@@ -0,0 +1,44 @@
+The DVB subsystem currently registers to the sysfs subsystem using the
+"class_simple" interface.
+
+This means that only the basic informations like module loading parameters
+are presented through sysfs. Other things that might be interesting are
+currently *not* available.
+
+Nevertheless it's now possible to add proper udev rules so that the
+DVB device nodes are created automatically.
+
+We assume that you have udev already up and running and that have been
+creating the DVB device nodes manually up to now due to the missing sysfs
+support.
+
+0. Don't forget to disable your current method of creating the
+device nodes manually.
+
+1. Unfortunately, you'll need a helper script to transform the kernel
+sysfs device name into the well known dvb adapter / device naming scheme.
+The script should be called "dvb.sh" and should be placed into a script
+dir where udev can execute it, most likely /etc/udev/scripts/
+
+So, create a new file /etc/udev/scripts/dvb.sh and add the following:
+------------------------------schnipp------------------------------------------------
+#!/bin/sh
+/bin/echo $1 | /bin/sed -e 's,dvb\([0-9]\)\.\([^0-9]*\)\([0-9]\),dvb/adapter\1/\2\3,'
+------------------------------schnipp------------------------------------------------
+
+Don't forget to make the script executable with "chmod".
+
+1. You need to add a proper rule to your udev rule file. The main
+udev configuration file /etc/udev/udev.conf will tell you the
+directory of the rules, most likely it's /etc/udev/rules.d/
+
+Edit the main rule file and add the following rule to the end
+of the file.
+
+KERNEL="dvb*", PROGRAM="/etc/udev/scripts/dvb.sh %k", NAME="%c"
+
+For every device that registers to the sysfs subsystem with a "dvb" prefix,
+the helper script /etc/udev/scripts/dvb.sh is invoked, which will then
+create the proper device name.
+
+Now udev will create the device node in your /dev/ device tree.