Tx power conttrol issue

Jirka Bohac jbohac at jikos.cz
Fri Aug 1 15:20:12 EDT 2003

> The txpower code is embraced by a MACRO RAW_TXPOWER_SETTING.
> However this macro is not defined yet.
> That's what you mean "I believe txpower control is removed from v0.0.4."

Yes, up to 0.0.3, txpower can be controlled directly with "iwconfig xxx
txpower". However, there are a couple of problems. The setting does not
remain in effect after a "card reset", which is performed from time to
time by the driver. So after the first reset, the power is back on "auto".
Furthermore, the driver still thinks its on "fixed" and won't let you
set it to "fixed" again, until you first turn it to "auto" and then back
to "fixed" again.....

I tried to address these issues in my patch, located at
http://jikos.cz/~jbohac/hostap (tha patch also re-enables txpower
control for 0.0.4)

Maybe it's because of these problems that Jouni disabled the txpower
control support. He also says that the setting is not accurate - indeed,
the "decibells" you use in iwconfig have NOTHING TO DO with real output
power expressed in dBm. Jouni probably wants to use a special prism
power feedback register, CR58, for more accurate setting.

However, in our network where most people use the same kind of card, we
have our own calibrations, and we learned to live with the old system.
The absence of txpower control in 0.0.4 is a big pain for us :( 
Anything would be better than nothing at all.

	Is any help needed to get txpower control back in the driver?


CZFree.Net, Czechia

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