SendTxFeedback?

[Javier Cardona]

Hi Marcelo,

> It is my understanding that given a packet transmission failure, the
> driver attempts to send the failed packet back to the upper layers (what
> is called "tx feedback"), if radiotap mode is enabled.

The Tx Feedback is only operational in the raw firmware, not in the cooked 
firmware.  

The design goal of the raw firmware was to support mesh routing on the host 
(e.g. roofnet), for which tx feedback is needed.

The design goal of the cooked firmware is to eventually implement mesh routing 
in the firmware itself, so no transmission feedback needs to be reported to 
the driver.  

> At this level, the packet transmission can only fail due to a removed
> card or failure in the USB transfer.

Not really.  Tx Feedback tells the driver the number of retries that were 
needed to send a frame or an error if no ACK was received from the 
destination host.  This is used by the mesh routing protocol to determine the 
quality of a link.

> I fail to see any use for such an "error reporting", can you explain
> what is going on?

You are probably using the cooked firmware, so no tx feedback.

> PS: do you have any numbers for the savings gained by enabling the power
> mode saving mode, when idle?

I'll let someone else answer this... 


Cheers,

Javier

-- 
Javier Cardona
cozybit Inc.
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