Hi Erich, On Tue, Nov 27, 2012 at 11:53 PM, Erich Titl <erich.titl@xxxxxxxx> wrote: > Hi Julian > > Thank you for the quick reply and the link > > on 27.11.2012 10:55, Julian Calaby wrote: >> Hi Erich, >> > ... > > >> >> It's not being completely overridden and it is working as designed. >> >> Firstly, the default country code for all Atheros chips is the USA. >> This is most likely because that's where the company is based. >> >> Secondly, your choice, China, is not being overridden. As the card is >> saying that it's configured for the USA, and you're saying that it's >> in China, the regulatory framework is using the intersection of the US >> and Chinese rules to govern it's output, thereby ensuring that the >> operation of the card complies with all the information it has about >> it's location. >> >> This has been explained in more detail in this thread: >> >> http://www.spinics.net/lists/linux-wireless/msg92420.html >> >> If you want to have the complete set of frequencies as specified by >> the Chinese rules, you will need to obtain a card which has been >> configured for Chinese operation. > > Actually the country code CH should stand for Switzerland and I am > surprised a default for the US should be hard coded into the driver Sorry about that, the last time I explained this, it was for a Chinese resident, and I got the codes mixed up. This "default" is part of the specification of how the hardware operates. If it hasn't been configured otherwise, it defaults to US operation. I'm sure that the Windows driver behaves in exactly the same way - this isn't some feature of the Linux driver, it's how the card is supposed to work. > Anyway, I am located in Switzerland and I saw similar threads from a few > people on the net. Today's mobile society demands that equipment can be > reconfigured freely to accommodate the local regulatory limits. This can > be achieved at will with an open card, which just gets crippled by the > hard coded limits set here. Laws say otherwise. Each country has a different set of regulations for how they expect a WiFi card to operate. To make a card that is fully compliant with all these sets of regulations would require it to be tested against in a way which can prove that it complies with all those regulations. In general, as I understand it, cards are usually built for a particular market, and tested that they comply with that market's regulations, usually then ignoring any other country's regulations. Cheaper manufacturers may just use a reference design, which is probably built to comply with US regulations, and then just use the defaults. The card is not "open", it's using the default configuration. The default configuration is that it's configured for US operation. > So under the worst thinkable circumstances this code won't work for my > environment as, for example, the intersection of the world regdomain and > the US regdomain would AFAIK cut away channels 12 and 13, which are > perfectly legal at my domicile and are used by some AP's. If you're using access points on channels 12 and 13, then yeah, using a card that is configured for US operation won't work for you. > I could (and will probably have to) recompile the driver using another > regdomain file, but this is not really satisfactory either. IMHO the > regdomain should be chosen as seen fit and not imposed by hard coded > limits in the driver. You could recompile the driver to use the Swiss country code as the default, however then you'd be using the card in a way which is outside of it's specification. It is possible that your particular card cannot work predictably enough on channels 12 and 13 to comply with the Swiss regulations which is why it's been left at the default configuration. It's also possible that it can comply with the regulations perfectly, but has never been tested and had the EEPROM set to indicate that it can comply with them. The simple fact of the matter is that the card is set to use the default configuration. The default configuration is for US operation, simple as that. This isn't short sighted Linux developers assuming that everyone is in the US, this is a design decision by the company that produced the card to give it a sensible default it can comply with. Thanks, -- Julian Calaby Email: julian.calaby@xxxxxxxxx Profile: http://www.google.com/profiles/julian.calaby/ .Plan: http://sites.google.com/site/juliancalaby/ -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
