1.. include:: <isonum.txt>
2
3========================
4Linux kernel WiMAX stack
5========================
6
7:Copyright: |copy| 2008 Intel Corporation < linux-wimax@intel.com >
8
9   This provides a basic Linux kernel WiMAX stack to provide a common
10   control API for WiMAX devices, usable from kernel and user space.
11
121. Design
13=========
14
15   The WiMAX stack is designed to provide for common WiMAX control
16   services to current and future WiMAX devices from any vendor.
17
18   Because currently there is only one and we don't know what would be the
19   common services, the APIs it currently provides are very minimal.
20   However, it is done in such a way that it is easily extensible to
21   accommodate future requirements.
22
23   The stack works by embedding a struct wimax_dev in your device's
24   control structures. This provides a set of callbacks that the WiMAX
25   stack will call in order to implement control operations requested by
26   the user. As well, the stack provides API functions that the driver
27   calls to notify about changes of state in the device.
28
29   The stack exports the API calls needed to control the device to user
30   space using generic netlink as a marshalling mechanism. You can access
31   them using your own code or use the wrappers provided for your
32   convenience in libwimax (in the wimax-tools package).
33
34   For detailed information on the stack, please see
35   include/linux/wimax.h.
36
372. Usage
38========
39
40   For usage in a driver (registration, API, etc) please refer to the
41   instructions in the header file include/linux/wimax.h.
42
43   When a device is registered with the WiMAX stack, a set of debugfs
44   files will appear in /sys/kernel/debug/wimax:wmxX can tweak for
45   control.
46
472.1. Obtaining debug information: debugfs entries
48-------------------------------------------------
49
50   The WiMAX stack is compiled, by default, with debug messages that can
51   be used to diagnose issues. By default, said messages are disabled.
52
53   The drivers will register debugfs entries that allow the user to tweak
54   debug settings.
55
56   Each driver, when registering with the stack, will cause a debugfs
57   directory named wimax:DEVICENAME to be created; optionally, it might
58   create more subentries below it.
59
602.1.1. Increasing debug output
61------------------------------
62
63   The files named *dl_* indicate knobs for controlling the debug output
64   of different submodules of the WiMAX stack::
65
66	# find /sys/kernel/debug/wimax\:wmx0 -name \*dl_\*
67	/sys/kernel/debug/wimax:wmx0/wimax_dl_stack
68	/sys/kernel/debug/wimax:wmx0/wimax_dl_op_rfkill
69	/sys/kernel/debug/wimax:wmx0/wimax_dl_op_reset
70	/sys/kernel/debug/wimax:wmx0/wimax_dl_op_msg
71	/sys/kernel/debug/wimax:wmx0/wimax_dl_id_table
72	/sys/kernel/debug/wimax:wmx0/wimax_dl_debugfs
73	/sys/kernel/debug/wimax:wmx0/.... # other driver specific files
74
75   NOTE:
76       Of course, if debugfs is mounted in a directory other than
77       /sys/kernel/debug, those paths will change.
78
79   By reading the file you can obtain the current value of said debug
80   level; by writing to it, you can set it.
81
82   To increase the debug level of, for example, the id-table submodule,
83   just write:
84
85	$ echo 3 > /sys/kernel/debug/wimax:wmx0/wimax_dl_id_table
86
87   Increasing numbers yield increasing debug information; for details of
88   what is printed and the available levels, check the source. The code
89   uses 0 for disabled and increasing values until 8.
90