Just to be specific, here is the problem I'm having: Sometimes my Linksys/Cisco WMP600N adapter will not initialize in AP mode. Prior to going into AP mode, I do 'iw wlan0 scan' and get a bunch of info, so the hardware is working up to that point. When I try to start hostapd, I get this error in dmesg: phy0 -> rt2800_wait_wpdma_ready: Error - WPDMA TX/RX busy, aborting. phy0 -> rt2800pci_set_device_state: Error - Device failed to enter state 4 (-5). (note that I also get this message: phy0 -> rt2800pci_mcu_status: Error - MCU request failed, no response from hardware but I get that when everything works, as well.) After the WPMDA TX/RX error occurs I usually cannot use the hardware at all. Even a simple 'ifconfig wlan0 up' will result in the same error. On rare occasions, the hardware will work if I simply retry hostapd. But usually I have to reboot to get the hardware working again. Helmut provided me with a patch to change the timeout for DMA to become ready; this did not solve the problem. Restarting the kernel modules like this: rmmod rt2800pci rt2800lib rt2x00pci rt2x00lib compat_firmware_class mac80211 cfg80211 compat modprobe rt2800pci also has no effect. I'm open to suggestions for other ways I might be able to kick the pci card without rebooting. Note that this exact software/hardware sometimes works, and sometimes fails. I have reproduced this problem on multiple WiFi adapters (same make/model), so I am confident it is not an isolated hardware failure. lspci -vv shows this data about the adapter: 03:01.0 Network controller: RaLink RT2800 802.11n PCI Subsystem: Linksys Unknown device 0067 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV+ VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=slow >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx- Latency: 32 (500ns min, 1000ns max), Cache Line Size: 64 bytes Interrupt: pin A routed to IRQ 22 Region 0: Memory at f3000000 (32-bit, non-prefetchable) [size=64K] Capabilities: [40] Power Management version 3 Flags: PMEClk- DSI- D1- D2- AuxCurrent=0mA PME(D0-,D1-,D2-,D3hot-,D3cold-) Status: D0 PME-Enable- DSel=0 DScale=0 PME- Kernel driver in use: rt2800pci Kernel modules: rt2800pci, rt2860sta I am running compat-wireless 2010-09-20 with a 2.6.27.8 kernel (slax 6.0.9-based distro) In the "probably not related, but just in case" category: I have another problem with these cards and hostapd where occasionally they will send a beacon but not respond to clients trying to join the network. However, stopping hostapd and restarting it clears this condition. (Now that I can successfully restart hostapd, thanks to a patch from Helmut!) In one case, restarting hostapd resulted in the WPDMA TX/RX error, and then I had to reboot. I'd be happy to try any wild ideas anyone has on this. Please reply to me directly, as I am not subscribed to this list. -Joshua On Sep 27, 2010, at 1:56 PM, Helmut Schaa wrote: > Hi, > > Am Montag 27 September 2010 schrieb Joshua Smith: >> The change to the REGISTER_BUSY_COUNT did not eliminate the issue. >> The device still sometimes exhibits this behavior. (It may be exhibiting >> it less often, but the occurrences are so random, that it's hard for me to >> know for sure.) > > Yeah, as I said, just a shot in the dark. > >> However, the other fix DID indeed eliminate the kernel crash when I tried >> to restart hostapd, and it also fixed a crash that I experienced when I >> tried to rmmod the rt2800pci module. So you should definitely mainline >> that patch. > > Sure. > >> Now that I can retry hostapd and rmmod the modules, I have found that there >> is apparently no software workaround for the case where the DMA busy >> condition does not pass. > > Hmm, maybe there is but we have't found it yet ;) > >> I have tried restarting hostapd, and I have tried rmmod'ding all the >> associated modules and modprobing them back in. Nothing clears the >> condition except a reboot. > > Too bad. > >> Any other ideas of what I could do to reset the hardware? I'd love to find >> a "soft" fix for this, rather than having to reboot to clear the condition. > > Nothing obviouis at least. So, no without further debugging I don't know what's > going on in your case. Would be interesting if others experience the same > problem. > > Helmut -- 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
