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4546548789
This is a new generic kernel FIFO implementation.
The current kernel fifo API is not very widely used, because it has to
many constrains. Only 17 files in the current 2.6.31-rc5 used it.
FIFO's are like list's a very basic thing and a kfifo API which handles
the most use case would save a lot of development time and memory
resources.
I think this are the reasons why kfifo is not in use:
- The API is to simple, important functions are missing
- A fifo can be only allocated dynamically
- There is a requirement of a spinlock whether you need it or not
- There is no support for data records inside a fifo
So I decided to extend the kfifo in a more generic way without blowing up
the API to much. The new API has the following benefits:
- Generic usage: For kernel internal use and/or device driver.
- Provide an API for the most use case.
- Slim API: The whole API provides 25 functions.
- Linux style habit.
- DECLARE_KFIFO, DEFINE_KFIFO and INIT_KFIFO Macros
- Direct copy_to_user from the fifo and copy_from_user into the fifo.
- The kfifo itself is an in place member of the using data structure, this save an
indirection access and does not waste the kernel allocator.
- Lockless access: if only one reader and one writer is active on the fifo,
which is the common use case, no additional locking is necessary.
- Remove spinlock - give the user the freedom of choice what kind of locking to use if
one is required.
- Ability to handle records. Three type of records are supported:
- Variable length records between 0-255 bytes, with a record size
field of 1 bytes.
- Variable length records between 0-65535 bytes, with a record size
field of 2 bytes.
- Fixed size records, which no record size field.
- Preserve memory resource.
- Performance!
- Easy to use!
This patch:
Since most users want to have the kfifo as part of another object,
reorganize the code to allow including struct kfifo in another data
structure. This requires changing the kfifo_alloc and kfifo_init
prototypes so that we pass an existing kfifo pointer into them. This
patch changes the implementation and all existing users.
[akpm@linux-foundation.org: fix warning]
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Acked-by: Andi Kleen <ak@linux.intel.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
|
||
|---|---|---|
| .. | ||
| assoc.c | ||
| assoc.h | ||
| cfg.c | ||
| cfg.h | ||
| cmd.c | ||
| cmd.h | ||
| cmdresp.c | ||
| debugfs.c | ||
| debugfs.h | ||
| decl.h | ||
| defs.h | ||
| dev.h | ||
| ethtool.c | ||
| host.h | ||
| if_cs.c | ||
| if_sdio.c | ||
| if_sdio.h | ||
| if_spi.c | ||
| if_spi.h | ||
| if_usb.c | ||
| if_usb.h | ||
| Kconfig | ||
| LICENSE | ||
| main.c | ||
| Makefile | ||
| mesh.c | ||
| mesh.h | ||
| radiotap.h | ||
| README | ||
| rx.c | ||
| scan.c | ||
| scan.h | ||
| tx.c | ||
| types.h | ||
| wext.c | ||
| wext.h | ||
================================================================================
README for Libertas
(c) Copyright © 2003-2006, Marvell International Ltd.
All Rights Reserved
This software file (the "File") is distributed by Marvell International
Ltd. under the terms of the GNU General Public License Version 2, June 1991
(the "License"). You may use, redistribute and/or modify this File in
accordance with the terms and conditions of the License, a copy of which
is available along with the File in the license.txt file or by writing to
the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 or on the worldwide web at http://www.gnu.org/licenses/gpl.txt.
THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
ARE EXPRESSLY DISCLAIMED. The License provides additional details about
this warranty disclaimer.
================================================================================
=====================
DRIVER LOADING
=====================
o. Copy the firmware image (e.g. usb8388.bin) to /lib/firmware/
o. Load driver by using the following command:
insmod usb8388.ko [fw_name=usb8388.bin]
=========================
ETHTOOL
=========================
Use the -i option to retrieve version information from the driver.
# ethtool -i eth0
driver: libertas
version: COMM-USB8388-318.p4
firmware-version: 5.110.7
bus-info:
Use the -e option to read the EEPROM contents of the card.
Usage:
ethtool -e ethX [raw on|off] [offset N] [length N]
-e retrieves and prints an EEPROM dump for the specified ethernet
device. When raw is enabled, then it dumps the raw EEPROM data
to stdout. The length and offset parameters allow dumping cer-
tain portions of the EEPROM. Default is to dump the entire EEP-
ROM.
# ethtool -e eth0 offset 0 length 16
Offset Values
------ ------
0x0000 38 33 30 58 00 00 34 f4 00 00 10 00 00 c4 17 00
========================
DEBUGFS COMMANDS
========================
those commands are used via debugfs interface
===========
rdmac
rdbbp
rdrf
These commands are used to read the MAC, BBP and RF registers from the
card. These commands take one parameter that specifies the offset
location that is to be read. This parameter must be specified in
hexadecimal (its possible to preceed preceding the number with a "0x").
Path: /sys/kernel/debug/libertas_wireless/ethX/registers/
Usage:
echo "0xa123" > rdmac ; cat rdmac
echo "0xa123" > rdbbp ; cat rdbbp
echo "0xa123" > rdrf ; cat rdrf
wrmac
wrbbp
wrrf
These commands are used to write the MAC, BBP and RF registers in the
card. These commands take two parameters that specify the offset
location and the value that is to be written. This parameters must
be specified in hexadecimal (its possible to preceed the number
with a "0x").
Usage:
echo "0xa123 0xaa" > wrmac
echo "0xa123 0xaa" > wrbbp
echo "0xa123 0xaa" > wrrf
sleepparams
This command is used to set the sleepclock configurations
Path: /sys/kernel/debug/libertas_wireless/ethX/
Usage:
cat sleepparams: reads the current sleepclock configuration
echo "p1 p2 p3 p4 p5 p6" > sleepparams: writes the sleepclock configuration.
where:
p1 is Sleep clock error in ppm (0-65535)
p2 is Wakeup offset in usec (0-65535)
p3 is Clock stabilization time in usec (0-65535)
p4 is Control periodic calibration (0-2)
p5 is Control the use of external sleep clock (0-2)
p6 is reserved for debug (0-65535)
subscribed_events
The subscribed_events directory contains the interface for the
subscribed events API.
Path: /sys/kernel/debug/libertas_wireless/ethX/subscribed_events/
Each event is represented by a filename. Each filename consists of the
following three fields:
Value Frequency Subscribed
To read the current values for a given event, do:
cat event
To set the current values, do:
echo "60 2 1" > event
Frequency field specifies the reporting frequency for this event.
If it is set to 0, then the event is reported only once, and then
automatically unsubscribed. If it is set to 1, then the event is
reported every time it occurs. If it is set to N, then the event is
reported every Nth time it occurs.
beacon_missed
Value field specifies the number of consecutive missing beacons which
triggers the LINK_LOSS event. This event is generated only once after
which the firmware resets its state. At initialization, the LINK_LOSS
event is subscribed by default. The default value of MissedBeacons is
60.
failure_count
Value field specifies the consecutive failure count threshold which
triggers the generation of the MAX_FAIL event. Once this event is
generated, the consecutive failure count is reset to 0.
At initialization, the MAX_FAIL event is NOT subscribed by
default.
high_rssi
This event is generated when the average received RSSI in beacons goes
above a threshold, specified by Value.
low_rssi
This event is generated when the average received RSSI in beacons goes
below a threshold, specified by Value.
high_snr
This event is generated when the average received SNR in beacons goes
above a threshold, specified by Value.
low_snr
This event is generated when the average received SNR in beacons goes
below a threshold, specified by Value.
extscan
This command is used to do a specific scan.
Path: /sys/kernel/debug/libertas_wireless/ethX/
Usage: echo "SSID" > extscan
Example:
echo "LINKSYS-AP" > extscan
To see the results of use getscantable command.
getscantable
Display the current contents of the driver scan table (ie. get the
scan results).
Path: /sys/kernel/debug/libertas_wireless/ethX/
Usage:
cat getscantable
setuserscan
Initiate a customized scan and retrieve the results
Path: /sys/kernel/debug/libertas_wireless/ethX/
Usage:
echo "[ARGS]" > setuserscan
where [ARGS]:
bssid=xx:xx:xx:xx:xx:xx specify a BSSID filter for the scan
ssid="[SSID]" specify a SSID filter for the scan
keep=[0 or 1] keep the previous scan results (1), discard (0)
dur=[scan time] time to scan for each channel in milliseconds
type=[1,2,3] BSS type: 1 (Infra), 2(Adhoc), 3(Any)
Any combination of the above arguments can be supplied on the command
line. If dur tokens are absent, the driver default setting will be used.
The bssid and ssid fields, if blank, will produce an unfiltered scan.
The type field will default to 3 (Any) and the keep field will default
to 0 (Discard).
Examples:
1) Perform a passive scan on all channels for 20 ms per channel:
echo "dur=20" > setuserscan
2) Perform an active scan for a specific SSID:
echo "ssid="TestAP"" > setuserscan
3) Scan all available channels (B/G, A bands) for a specific BSSID, keep
the current scan table intact, update existing or append new scan data:
echo "bssid=00:50:43:20:12:82 keep=1" > setuserscan
4) Scan for all infrastructure networks.
Keep the previous scan table intact. Update any duplicate BSSID/SSID
matches with the new scan data:
echo "type=1 keep=1" > setuserscan
All entries in the scan table (not just the new scan data when keep=1)
will be displayed upon completion by use of the getscantable ioctl.
========================
IWCONFIG COMMANDS
========================
power period
This command is used to configure the station in deep sleep mode /
auto deep sleep mode.
The timer is implemented to monitor the activities (command, event,
etc.). When an activity is detected station will exit from deep
sleep mode automatically and restart the timer. At timer expiry
(no activity for defined time period) the deep sleep mode is entered
automatically.
Note: this command is for SDIO interface only.
Usage:
To enable deep sleep mode do:
iwconfig wlan0 power period 0
To enable auto deep sleep mode with idle time period 5 seconds do:
iwconfig wlan0 power period 5
To disable deep sleep/auto deep sleep mode do:
iwconfig wlan0 power period -1
==============================================================================