On Tuesday, 15 of April 2008, George Spelvin wrote: > When trying a recent 2.6.25 on a laptop, I discovered that it > completely breaks suspend to RAM. It blanks the screen and lights up > the sleeping light, but judging by the noises the laptop makes (help, > low battery!) after being unplugged for a while, it doesn't actually > suspend a whole lot. > > More interestingly, it gets the laptop into a state where the only ways > I can make it respond are disconnecting and connecting AC power (beep), > and holding the power button down for 4 seconds. > > The really interesting part is that after that, it won't turn on again! > I have to disconnect power and remove the battery to reset it hard enough > that it will respond to furtherpresses of the power button. > > This smells like a BIOS bug to me, but it's interesting that it gets tickled. > > The patch is unfortunately one that fixes other machines: > > > ACPI suspend: Call _PTS before suspending devices > > > > The ACPI 1.0 specification wants us to put devices into low power > > states after executing the _PTS global control method, while ACPI > > 2.0 and later want us to do that in the reverse order. The current > > suspend code follows ACPI 2.0 in that respect which causes some > > ACPI 1.0x systems to hang during suspend (ref. > > http://bugzilla.kernel.org/show_bug.cgi?id=9528). > > > > Make the suspend code execute _PTS before putting devices into low > > power states (ie. in accordance with ACPI 1.0x) and provide a command > > line option to override the default if need be. > > Fortunately, the "acpi_new_pts_ordering" kernel parameter fixes it, > but I waded through a full bisect (actually two, owing to some mistakes > the first time) before finding out about it. This change has been reverted from the current Linus' tree, so please check if 2.6.25-rc9 (or a later git snapshot) works for you. Thanks, Rafael -- 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
