On Thu, 2007-11-29 at 08:44 +0100, Holger Schurig wrote: > On Thursday 29 November 2007 05:12:06 Albert Cahalan wrote: > > On Nov 28, 2007 11:30 AM, Holger Schurig > <hs4233@xxxxxxxxxxxxxxxxxxxx> wrote: > > > Remove the ability to specify channels to scan via debugfs > > > > Why are you ripping out functionality? At the very least, > > that ought to be justified in the changelog comment. > > This was discussed in libertas-dev. > > > Basically, I posted there a RFC (request-for-comment) patch about > a newer implementation of how scanning could be implemented. The > current version of scan.c is a bit complicated and not easy to > follow. I was rewriting that up to a point where it worked. But > my RFC patch had a bunch of TODO items, and I asked in > libertas-dev how to deal with them. > > Two TODOs were about the implementation the syntax > of "probes=XXX" and "channel=XXX" that you can use via > debugfs/extgetscan. > > Dan thought that we could easily rip this out, because no one is > known to use this feature. And I'm seconding Dan here. Both > debugfs-features actually just exhibits a possibility of how to > interact with the firmware. They don't have a real value. > > Simply because you cannot set number of probes or channel-list > from "normal" user-space application. E.g. when libertas needs > to scan because of a new ESSID set via "iwlist eth1 essid BLAH" > it would anyway scan all channels set by the country (11, 13 or > 14 for b/g). It wouldn't honor your manually crafted last scan > from your last access to debugfs. > > So extgetscan is merely a tool to play with, but nothing more. > > madwifi for example also has the ability to specify "please scan > only on channels 1, 7, 11", but this has been implemented via > private ioctl's and set's this "sticky". So when you scan from > iwlist, implicitly from iwconfig XXX essid, from wpa_supplicant > etc, it would be honored. For such a feature you have a > real-life usage scenario, it would be much more useful than the > current way. Note that WEXT supports specifying the channels you'd like to scan on in the extscan struct of the SIOCSIWSCAN call. Libertas should support this. However, I don't think iwlist supports it, but that shouldn't stop the drivers from supporting that option. Dan - 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
