Signed-off-by: Inaky Perez-Gonzalez <inaky@xxxxxxxxxxxxxxx> --- Documentation/wimax/README.wimax | 81 ++++++++++++++++++++++++++++++++++++++ 1 files changed, 81 insertions(+), 0 deletions(-) create mode 100644 Documentation/wimax/README.wimax diff --git a/Documentation/wimax/README.wimax b/Documentation/wimax/README.wimax new file mode 100644 index 0000000..b78c437 --- /dev/null +++ b/Documentation/wimax/README.wimax @@ -0,0 +1,81 @@ + + Linux kernel WiMAX stack + + (C) 2008 Intel Corporation < linux-wimax@xxxxxxxxx > + + This provides a basic Linux kernel WiMAX stack to provide a common + control API for WiMAX devices, usable from kernel and user space. + +1. Design + + The WiMAX stack is designed to provide for common WiMAX control + services to current and future WiMAX devices from any vendor. + + Because currently there is only one and we don't know what would be the + common services, the APIs it currently provides are very minimal. + However, it is done in such a way that it is easily extensible to + accommodate future requirements. + + The stack works by embedding a struct wimax_dev in your device's + control structures. This provides a set of callbacks that the WiMAX + stack will call in order to implement control operations requested by + the user. As well, the stack provides API functions that the driver + calls to notify about changes of state in the device. + + The stack exports the API calls needed to control the device to user + space using generic netlink as a marshalling mechanism. You can access + them using your own code or use the wrappers provided for your + convenience in libwimax (in the wimax-tools package). + + For detailed information on the stack, please see + include/linux/wimax.h. + +2. Usage + + For usage in a driver (registration, API, etc) please refer to the + instructions in the header file include/linux/wimax.h. + + When a device is registered with the WiMAX stack, a set of debugfs + files will appear in /sys/kernel/debug/wimax:wmxX can tweak for + control. + +2.1. Obtaining debug information: debugfs entries + + The WiMAX stack is compiled, by default, with debug messages that can + be used to diagnose issues. By default, said messages are disabled. + + The drivers will register debugfs entries that allow the user to tweak + debug settings. + + Each driver, when registering with the stack, will cause a debugfs + directory named wimax:DEVICENAME to be created; optionally, it might + create more subentries below it. + +2.1.1. Increasing debug output + + The files named *dl_* indicate knobs for controlling the debug output + of different submodules of the WiMAX stack: + * +# find /sys/kernel/debug/wimax\:wmx0 -name \*dl_\* +/sys/kernel/debug/wimax:wmx0/wimax_dl_stack +/sys/kernel/debug/wimax:wmx0/wimax_dl_op_rfkill +/sys/kernel/debug/wimax:wmx0/wimax_dl_op_reset +/sys/kernel/debug/wimax:wmx0/wimax_dl_op_msg +/sys/kernel/debug/wimax:wmx0/wimax_dl_id_table +/sys/kernel/debug/wimax:wmx0/wimax_dl_debugfs +/sys/kernel/debug/wimax:wmx0/.... # other driver specific files + + NOTE: Of course, if debugfs is mounted in a directory other than + /sys/kernel/debug, those paths will change. + + By reading the file you can obtain the current value of said debug + level; by writing to it, you can set it. + + To increase the debug level of, for example, the id-table submodule, + just write: + +$ echo 3 > /sys/kernel/debug/wimax:wmx0/wimax_dl_id_table + + Increasing numbers yield increasing debug information; for details of + what is printed and the available levels, check the source. The code + uses 0 for disabled and increasing values until 8. -- 1.5.6.5