Setting txpower fails?

DISCUSSION Ben Greear 4 participants 9 messages Mar 28, 2014 – Mar 29, 2014 2 messages not in the archive

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Ben Greear

author

2014-03-28 04:22 UTC #0 lore raw

Any idea why this isn't working?

Kernel is 3.9.11+, driver is ath9k.

[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off

[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10 [root@ct523-9292 lanforge]# echo $?
0
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off

[root@ct523-9292 lanforge]#

Signature · 2 lines

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com

Sedat Dilek

2014-03-28 07:27 UTC #1 lore raw

Quoted 21 lines · Ben Greear

Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10 [root@ct523-9292 lanforge]# echo $?
0
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off

Quoted 2 lines

[root@ct523-9292 lanforge]#

Which version of wireless-tools?
Why don't you use modern iw?

- Sedat -

Ben Greear

author

2014-03-28 14:18 UTC #2 lore raw

Quoted 22 lines · Sedat Dilek

Quoted 21 lines · Ben Greear
Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10 [root@ct523-9292 lanforge]# echo $?
0
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off

Quoted 5 lines

Quoted 2 lines
[root@ct523-9292 lanforge]#
Which version of wireless-tools?
Why don't you use modern iw?

Do you know the right incantation for 'iw'? From it's help, it seems this should work, but it throws an error. I haven't dug into the code to figure out why...

[root@ct523-9292 lanforge]# iw dev wlan0 set txpower 10 Invalid parameter: 10

[root@ct523-9292 lanforge]# iwconfig --version iwconfig Wireless-Tools version 29
Compatible with Wireless Extension v11 to v22.

Kernel Currently compiled with Wireless Extension v22.

sta211 Recommend Wireless Extension v21 or later,
Currently compiled with Wireless Extension v22.
...

Thanks,
Ben

Quoted 3 lines

- Sedat -

Signature · 2 lines

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com

Sedat Dilek

2014-03-28 14:39 UTC #3 lore raw

Quoted 33 lines · Ben Greear

Quoted 25 lines · Sedat Dilek
Quoted 22 lines · Ben Greear
Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10 [root@ct523-9292 lanforge]# echo $?
0
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
Quoted 5 lines
Quoted 2 lines
[root@ct523-9292 lanforge]#
Which version of wireless-tools?
Why don't you use modern iw?

Quoted 7 lines

Do you know the right incantation for 'iw'? From it's help, it seems this should work, but it throws an error. I haven't dug into the code to figure out why...
[root@ct523-9292 lanforge]# iw dev wlan0 set txpower 10 Invalid parameter: 10

I have found [1] in the wiki.
For more details and a quick answer try to ask on IRC?

- Sedat -

[1] http://wireless.kernel.org/en/users/Documentation/iw#Setting_TX_power

Quoted 23 lines

[root@ct523-9292 lanforge]# iwconfig --version iwconfig Wireless-Tools version 29
Compatible with Wireless Extension v11 to v22.
Kernel Currently compiled with Wireless Extension v22.
sta211 Recommend Wireless Extension v21 or later,
Currently compiled with Wireless Extension v22.
...
Thanks,
Ben
Quoted 3 lines
- Sedat -
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com

Bruno Antunes

2014-03-28 14:50 UTC #6 lore raw

In reply to a message not in the archive

Quoted 23 lines · Ben Greear

Quoted 22 lines · Bruno Antunes
Hi Ben,
I think you are missing some parameters
Quoted 6 lines · Ben Greear
Quoted 5 lines · Sedat Dilek
Quoted 4 lines · Ben Greear
Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
Quoted 8 lines
Quoted 8 lines
Quoted 8 lines
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10
iw dev <devname> set txpower <auto|fixed|limit> [<tx power in mBm>]

Quoted 8 lines

Quoted 3 lines
It should be something like:
iw dev wlan0 set txpower fixed 1000
Ok, that doesn't give an error, but 'iwconfig' still shows 16 dBm, and I don't see any way to get 'iw' to print out the power itself?
So, not sure if it is really working or not.

It works , at least on iw 3.10.

If you have debug enabled you can see the value changing.

On a openwrt system

root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 900
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
9
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 1500
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
15

And the received power changes on the station confirming that is making effect.

Bruno

Quoted 9 lines

Thanks,
Ben

Signature · 2 lines

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com

Ben Greear

author

2014-03-28 15:02 UTC #7 lore raw

Quoted 30 lines · Bruno Antunes

Quoted 27 lines · Ben Greear
Quoted 25 lines · Bruno Antunes
Hi Ben,
I think you are missing some parameters
Quoted 6 lines · Ben Greear
Quoted 5 lines · Sedat Dilek
Quoted 4 lines · Ben Greear
Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
Quoted 8 lines
Quoted 8 lines
Quoted 8 lines
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10
iw dev <devname> set txpower <auto|fixed|limit> [<tx power in mBm>]
It should be something like:
iw dev wlan0 set txpower fixed 1000

Quoted 7 lines

Quoted 4 lines
Ok, that doesn't give an error, but 'iwconfig' still shows 16 dBm, and I don't see any way to get 'iw' to print out the power itself?
So, not sure if it is really working or not.
It works , at least on iw 3.10.
If you have debug enabled you can see the value changing.

Just for posterity's sake, it seems you should really be looking at user_power_level:

[root@ct523-9292 lanforge]# iw dev wlan0 set txpower fixed 1000 [root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/txpower 0
[root@ct523-9292 lanforge]#

[root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/user_power_level 10

Thanks,
Ben

Quoted 23 lines

On a openwrt system
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 900
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
9
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 1500
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
15
And the received power changes on the station confirming that is making effect.
Bruno
Quoted 9 lines
Thanks,
Ben
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com

Signature · 2 lines

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com

Bruno Antunes

2014-03-28 15:15 UTC #8 lore raw

Quoted 42 lines · Ben Greear

Quoted 30 lines · Bruno Antunes
Quoted 27 lines · Ben Greear
Quoted 25 lines · Bruno Antunes
Hi Ben,
I think you are missing some parameters
Quoted 6 lines · Ben Greear
Quoted 5 lines · Sedat Dilek
Quoted 4 lines · Ben Greear
Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
Quoted 8 lines
Quoted 8 lines
Quoted 8 lines
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10
iw dev <devname> set txpower <auto|fixed|limit> [<tx power in mBm>]
It should be something like:
iw dev wlan0 set txpower fixed 1000
Quoted 7 lines
Quoted 4 lines
Ok, that doesn't give an error, but 'iwconfig' still shows 16 dBm, and I don't see any way to get 'iw' to print out the power itself?
So, not sure if it is really working or not.
It works , at least on iw 3.10.
If you have debug enabled you can see the value changing.
Just for posterity's sake, it seems you should really be looking at user_power_level:

Quoted 8 lines

[root@ct523-9292 lanforge]# iw dev wlan0 set txpower fixed 1000 [root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/txpower 0
[root@ct523-9292 lanforge]#
[root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/user_power_level 10

Not on all systems...

root@RSPro2:/etc/config#  iw dev adhoc0 set txpower fixed 700
root@RSPro2:/etc/config# cat /sys/kernel/debug/ieee80211/phy0/netdev\:adhoc0/txpower 
7
root@RSPro2:/etc/config# cat /sys/kernel/debug/ieee80211/phy0/netdev\:adhoc0/user_power_level 
7

Bruno

Quoted 32 lines

Thanks,
Ben
Quoted 23 lines
On a openwrt system
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 900
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
9
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 1500
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
15
And the received power changes on the station confirming that is making effect.
Bruno
Quoted 9 lines
Thanks,
Ben
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com
Signature · 2 lines
Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com

Ben Greear

author

2014-03-28 15:25 UTC #9 lore raw

Quoted 50 lines · Bruno Antunes

Quoted 47 lines · Ben Greear
Quoted 30 lines · Bruno Antunes
Quoted 27 lines · Ben Greear
Quoted 25 lines · Bruno Antunes
Hi Ben,
I think you are missing some parameters
Quoted 6 lines · Ben Greear
Quoted 5 lines · Sedat Dilek
Quoted 4 lines · Ben Greear
Any idea why this isn't working?
Kernel is 3.9.11+, driver is ath9k.
Quoted 8 lines
Quoted 8 lines
Quoted 8 lines
[root@ct523-9292 lanforge]# iwconfig wlan0
wlan0 IEEE 802.11abgn ESSID:off/any
Mode:Managed Access Point: Not-Associated Tx-Power=16 dBm
Retry short limit:7 RTS thr:off Fragment thr:off
Encryption key:off
Power Management:off
[root@ct523-9292 lanforge]# iwconfig wlan0 txpower 10
iw dev <devname> set txpower <auto|fixed|limit> [<tx power in mBm>]
It should be something like:
iw dev wlan0 set txpower fixed 1000
Quoted 7 lines
Quoted 4 lines
Ok, that doesn't give an error, but 'iwconfig' still shows 16 dBm, and I don't see any way to get 'iw' to print out the power itself?
So, not sure if it is really working or not.
It works , at least on iw 3.10.
If you have debug enabled you can see the value changing.
Just for posterity's sake, it seems you should really be looking at user_power_level:
[root@ct523-9292 lanforge]# iw dev wlan0 set txpower fixed 1000 [root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/txpower 0
[root@ct523-9292 lanforge]#

Quoted 4 lines

Quoted 3 lines
[root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/user_power_level 10
Not on all systems...

I suspect the difference is that my wlan0 is not actually connected, and it will probably show correct 'txpower' when it is connected.

Thanks,
Ben

Quoted 41 lines

root@RSPro2:/etc/config#  iw dev adhoc0 set txpower fixed 700
root@RSPro2:/etc/config# cat /sys/kernel/debug/ieee80211/phy0/netdev\:adhoc0/txpower
7
root@RSPro2:/etc/config# cat /sys/kernel/debug/ieee80211/phy0/netdev\:adhoc0/user_power_level
7
Bruno
Quoted 32 lines
Thanks,
Ben
Quoted 10 lines
On a openwrt system
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 900
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
9
root@RSPro2:/lib/wifi#  iw dev adhoc0 set txpower fixed 1500
root@RSPro2:/lib/wifi# cat /sys/kernel/debug/ieee80211/phy0/netdev:adhoc0/txpower
15
Quoted 13 lines
And the received power changes on the station confirming that is making effect.
Bruno
Quoted 9 lines
Thanks,
Ben
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com
--
Ben Greear <[email protected]>
Candela Technologies Inc http://www.candelatech.com

Signature · 2 lines

Ben Greear <[email protected]>
Candela Technologies Inc  http://www.candelatech.com

Kalle Valo

2014-03-29 05:47 UTC #10 lore raw

Quoted 5 lines · Ben Greear

Quoted 5 lines
Quoted 5 lines
[root@ct523-9292 lanforge]# iw dev wlan0 set txpower fixed 1000 [root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/txpower 0
[root@ct523-9292 lanforge]#

Quoted 7 lines

Quoted 4 lines
Quoted 3 lines
[root@ct523-9292 lanforge]# cat /debug/ieee80211/wiphy0/netdev\:wlan0/user_power_level 10
Not on all systems...
I suspect the difference is that my wlan0 is not actually connected, and it will probably show correct 'txpower' when it is connected.

I also recall openwrt having some custom tx power patches. They might make a difference as well.

Signature · 1 line

Kalle Valo