Re: [PATCH 8/8] eeepc-laptop: don't assume get_acpi succeeds

From: Darren Hart
Date: Wed Oct 29 2014 - 20:54:41 EST


On Tue, Oct 28, 2014 at 09:09:03AM +0100, Frans Klaver wrote:
> On Tue, Oct 28, 2014 at 6:34 AM, Darren Hart <dvhart@xxxxxxxxxxxxx> wrote:
> > On Wed, Oct 22, 2014 at 09:12:43PM +0200, Frans Klaver wrote:
> >> In eeepc_hotk_thaw, we assume that get_acpi() will effectively return a
> >> bool. However, it is possible that get_acpi() returns an error instead.
> >> We should not be writing error values to the ACPI device, even though
> >> it's quite possible that we couldn't contact the ACPI device in the
> >> first place.
> >>
> >> Signed-off-by: Frans Klaver <fransklaver@xxxxxxxxx>
> >> ---
> >> drivers/platform/x86/eeepc-laptop.c | 5 +++--
> >> 1 file changed, 3 insertions(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/platform/x86/eeepc-laptop.c b/drivers/platform/x86/eeepc-laptop.c
> >> index 275a239..14f79ef 100644
> >> --- a/drivers/platform/x86/eeepc-laptop.c
> >> +++ b/drivers/platform/x86/eeepc-laptop.c
> >> @@ -911,7 +911,7 @@ static int eeepc_hotk_thaw(struct device *device)
> >> struct eeepc_laptop *eeepc = dev_get_drvdata(device);
> >>
> >> if (eeepc->wlan_rfkill) {
> >> - bool wlan;
> >> + int wlan;
> >>
> >> /*
> >> * Work around bios bug - acpi _PTS turns off the wireless led
> >> @@ -919,7 +919,8 @@ static int eeepc_hotk_thaw(struct device *device)
> >> * we should kick it ourselves in case hibernation is aborted.
> >> */
> >> wlan = get_acpi(eeepc, CM_ASL_WLAN);
> >> - set_acpi(eeepc, CM_ASL_WLAN, wlan);
> >> + if (wlan >= 0)
> >> + set_acpi(eeepc, CM_ASL_WLAN, wlan);
> >
> > And if not? Seems like we should be passing the error code along.
>
> Wouldn't that mean that you cannot thaw the system if the wlan acpi call fails?

Good question. I traced it back to the platform driver core, and it just
propogates the error, so I'm not sure either.

>
> I'd rather have my system up and running without wlan, than I'd have
> my system down because we couldn't start wlan. This is of course
> assuming that returning an error from eeepc_hotk_thaw means the
> thawing stops.

I agree, and this is what it does now, and acer-wmi thaw has similar behavior.

I consider this an incremental improvement, so queued.

--
Darren Hart
Intel Open Source Technology Center
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