Re: [PATCH] rt2x00: Provide regulatory hint with rt2500pci/usb

["Luis R. Rodriguez" <lrodriguez@atheros.com>]

On Tue, Jan 06, 2009 at 12:39:34PM -0800, Gertjan van Wingerde wrote:
> On 01/06/09 18:47, Ivo van Doorn wrote:
> > On Tuesday 06 January 2009, Luis R. Rodriguez wrote:
> >
> >> On Tue, Jan 06, 2009 at 09:32:20AM -0800, Ivo van Doorn wrote:
> >>
> >>>>>> 2. I'm still puzzled how to handle the two different values that the EEPROM has, namely one for the bg band and one for the a band. I've handled it by registering the one associated with the configured band, but that seems to be unlikely to be correct. I still haven't found a better way to handle this.
> >>>>>>
> >>>>> Because of this I hadn't looked very deep into rt61 and rt73 yet.
> >>>>>
> >>>>>
> >>>>>> The problem isn't there for the bits that Ivo sent, as the rt2500 devices don't support the a band.
> >>>>>>
> >>>>> For rt2500pci and rt2500usb there are chipsets which support 5GHz (they are rare, but they do exist),
> >>>>> comments for the Ralink drivers indicate they simply didn't add the regulatory domain definitions yet.
> >>>>>
> >>>> Based on the documentation from the EEPROM for all devices I read that its recommended
> >>>> that the EEPROM *not be relied on for the regulatory domain*, instead it recommends the
> >>>> windows registry be used.
> >>>>
> >>>> Based on tests for the devices with only one band, do are you seeing an actual regulatory
> >>>> domain in the EEPROM?
> >>>>
> >>> I have to check, but I don't think I have any hardware with valid domain values.
> >>>
> >>>
> >>>> To deal with the issue of having two separate EEPROM values for a regulatory domain
> >>>> and since the documentation indicates to not rely on it I would advise to allow users
> >>>> to be compliant by selecting the country they are in. wpa_supplicant has support for
> >>>> selecting country now, and so does iw. Eventually I see Network Manager letting users
> >>>> select the country. But you guys are the maintainers and developers so you will know
> >>>> better.
> >>>>
> >>> Well it is fine with me,  understood from earlier discussion that it was advised that drivers
> >>> attempted to set the domain if they could. Hence the reason I had added reading the EEPROM
> >>> for domain values to the TODO list. But it is true that it is quite rare that there are valid values
> >>> for it. So it would be fine with me by letting the user handle it completely.
> >>>
> >> I see -- well if there are *some* cards that do have valid EEPROM values then it seems worth it
> >> to do the actual regulatory_hint(), for dual band cards you can probably just not support it. But
> >> its up to you guys. Just my advice based on the documentation I have read so far.
> >>
> >
> > Ok.
> >
> > Gertjan, do you know if there is any hardware with valid GEO data in the EEPROM?
> >
> 
> As mentioned in my previous email, I do have devices that have valid GEO
> data in the EEPROM. So, we should be able to use that.
> Also, for the dual band cards, it does seem that at least the numerical
> values are similar for both bands (although I'm not sure that same
> numerical values means same regulatory domain). This is at least the
> case on all the cards that I own.

If that's the case and since dual band cards will most likely have 2ghz support
why not just provide regulatory_hint() based on the 2ghz band all the time?

> FYI: The legacy drivers do use the information in the EEPROM to
> initialize the internal administration of regulatory information, but
> allow the end-user to override that via config-file or via private wext
> call. It would be good to have a similar possibility for rt2x00.

We allow users to change regulatory domain, please see:

http://wireless.kernel.org/en/developers/Regulatory/CRDA#Changingregulatorydomains

  Luis