2011/6/29 Rafał Miłecki <zajec5@xxxxxxxxx>: > 2011/6/29 Ike Panhc <ike.pan@xxxxxxxxxxxxx>: >> On 06/26/2011 06:53 AM, Andrew Lutomirski wrote: >>> [linux-acpi cc'd because I don't know how to write to an ACPI field, >>> and the fix to this bug probably needs that ability.] >>> >>> Hi platform people- >>> >>> My nephew's Ideapad S10-3 decided that it didn't want to support >>> wireless anymore. I think it happened when he fiddled with his rfkill >>> switch, but I haven't been able to reproduce the problem yet. This >>> seems to be a common bug, and the only known fixes (so far) are to >>> boot into Windows and fiddle with the settings or to remove the CMOS >>> battery. >>> >>> This seems to be related to: >>> http://ubuntuforums.org/showthread.php?t=1744402 >>> https://bugs.meego.com/show_bug.cgi?id=4086 >>> https://bugs.launchpad.net/ubuntu/+source/linux/+bug/730972 >>> >>> Of course, he doesn't have Windows installed, and I didn't want to >>> take apart his laptop. So I figured out the problem. >>> >>> The relevant ACPI fields and functions are (as far as I can tell): >>> >>> \FL07: The non-volatile copy of the RF enabled flag >>> \_SB.PCI0.LPCB.EC0.WRFS: RF enabled flag >>> \GO26: The GPIO line that controls the PHY (not really tested at all) >>> \GO28: The RF light, inverted. This doesn't work without manual >>> override on my S10-3 because I don't have bluetooth or 3G, AFAICT. >>> >>> \_SB.PCI0.LPCB.EC0.DSLD: Load WRFS from FL07 (on startup) >>> \_SB.PCI0.LPCB.EC0.DSSV: Save WRFS to FL07, called from some hotkey >>> handler or other >>> \_SB.PCI0.LPCB.EC0.DSGO: Commit WRFS to hardware (i.e. \GO26). >>> >>> Oddly enough, nothing in the DSDT seems to write WRFS or FL07 except >>> to copy FL07 to WRFS. So triggering the problem might involve >>> toggling the switch from inside BIOS or something similar. >>> >>> The fix would be (I think) to change ideapad_sync_rfk_state to do this >>> (in pseudocode): >>> if (!hw_blocked != WRFS) { >>> WRFS = !hw_blocked; >>> DSSV() >>> DSGO() >>> } >>> >>> I don't plan to send a patch for two reasons: >>> >>> 1. I don't know how to write to an ACPI field. acpi_ns_evaluate can >>> read fields, but it can't write them AFAICT. The ability to write to >>> a field would be really nice. I did it by frobbing the ports by hand. >>> >>> 2. My nephew's taking his laptop home tomorrow, so I won't be able to >>> test a patch. >>> >>> In the mean time, if you are affected by this problem and you really >>> don't care how badly you damage your laptop, you could run the >>> attached program, passing 1 as a parameter. Then you should probably >>> reboot. Before you even consider trying that, you should check >>> whether the magic hardcoded numbers match your DSDT. If you don't >>> know how to do that, then you probably shouldn't run the program. >>> >>> --Andy >>> >>> P.S. Some people with this bug find that their system freezes hard >>> when they try and fail to fix it. I think this is a bug in brcm80211 >>> in 2.6.38 that's been fixed in brcmsmac in 2.6.39. But I don't really >>> feel like testing that carefully, given that I've already fixed the >>> root cause. >> >> Thanks for your report. I have a S10-3 but barely touch the wifi switch. >> >> I know there are two drivers for Broadcom wifi chips. One is b43 which >> is fully open and in linux kernel tree. The other is wl comes from >> Broadcom with other license agreement and its source code is not fully >> open. I don't have access to the laptop anymore, but from memory: I tried wl, brcm80211 (from 2.6.38) and brcmsmac (from 2.6.39). I don't think b43 supported that hardware. wl and brcmsmac both showed ideapad-laptop soft and hard unblocked and the wireless driver's rfkill soft unblocked but hard blocked. brcm80211 froze the system hard. I think it can't deal with rfkill. >> In your mail you did not mention the output of 'rfkill list'. In my >> view point this is necessary info that tells us who block the wifi. >> I guess the your wifi problem is because one of the wlan rfkill shows >> blocked. Yes. >> What I know is that the fix you suggest is hardly to be accepted >> because those ACPI objects is not under VPC2004 and not always available >> on ideapads. I have 8 ideapad DSDT but only two with those objects. >> >> I will test the wifi switch on my ideapads again after I back to home >> which will be next week and see if I can reproduce the same issue. > > I've got one similar report on IRC #bcm-users from Ideapad user. When > he booted with rfkill on, Broadcom was not visible in lspci at all. > Switching rfkill during working system didn't change anything. He had > to power down, switch rfkill off and boot. I tried that and it didn't help. I even tried turning the switch on and leaving the battery out for awhile. --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
