On 13/03/13 11:35, James Harper wrote:
I spent ages last night getting wireless working on an embedded ARM device. The problem is that the first time wpa_supplicant runs, it can't see any SSIDs, and doesn't get anywhere. The second time it runs, it's all fine.
Does this problem occur under Linux on a regular PC too?
The embedded board runs linux kernel 3.2, and later kernels weren't working at all. When I tried a different embedded board, and a PC, both with later kernels and ubuntu distros, it Just Worked. But I didn't have any hardware running the same distro and kernel to test on. So I guess it looks like something is flakey in the versions of either (or both) the wpa_supplicant and the wifi chipset driver.
My eventual solution was to create a script that runs wpa_supplicant, waits five seconds, kills it, then runs it again. So, so dirty.
Yeah that never leaves you feeling good about a project.
This issue only appears to occur with one of my three USB wifi adapters. However of the others, one isn't supported by any version of Linux, and the other one is dodgy on 3.2 kernels.. but post 3.2.x kernels don't work reliably on this hardware.
Soo.. while I wait for a fourth bloody USB adapter with yet another wifi chipset in it to arrive.. does anyone have any ideas how to fix the current one?
I'm guessing there's something specific the wifi adapter needs initialised before it will work, but I just don't know what..
Is there a way to 'open' the adapter via some other means before loading wpa_supplicant?
You can try and initialise it via the old-school wireless configuration methods (as if you were using WEP or no encryption at all). I was trying that, but it didn't seem to be helping.
Otherwise maybe strace and see what the differences between the two runs are.
Yeah :( Getting into the realm of Too Hard though. T