Help required in understanding MadWifi initialization and card setup

Hi,

I needed some help in understanding what happens during MadWifi 
initialization? What functions get called and in what order? Which 
function initializes the card through the HAL and so on. Specifically, 
Im looking to implement 5/10 MHz channel widths on Madwifi and I know 
that this requires modifying parts of the ath_reset() and ath_init() 
methods as well as adding regulatory support in ah_regdomain.c. Can 
someone please guide me on this? Specifically,

1. How does the driver know which channels are supported by the card? 
Which HAL functions does it call and what data structures represent 
channels?
2. How and where does the driver tell the card to use a specific channel 
center frequency and width?

Many thanks for your help
--Aditya Bhave

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