applied to acpi-test thanks, Len Brown, Intel Open Source Technology Center On Thu, 17 Dec 2009, Zhang Rui wrote: > On Fri, 2009-12-11 at 11:52 +0800, Zhang Rui wrote: > > On Wed, 2009-11-11 at 04:09 +0800, Matthew Garrett wrote: > > > https://bugzilla.redhat.com/show_bug.cgi?id=531916 describes a system > > > with a _PSC method for the fan that always returns "on". There's no > > > benefit in us always requesting the state of the fan when performing > > > transitions - we want to do everything we can to ensure that the fan turns > > > on when it should do, not risk hardware damage by believing the hardware > > > when it tells us the fan is already on. Given that the Leading Other OS(tm) > > > works fine on this machine, it seems likely that it behaves in much this > > > way. > > > > > sounds reasonable. > > But how can we get the power state if power resources is not available? > > > > In acpi_bus_get_power, why not make acpi_power_get_inferred_state as the > > first choice, instead of evaluating _PSC? like the patch attached. > > > Matthew, > > how about this one? > > > If the ACPI power state can be got both directly and indirectly, > we prefer to get it indirectly. > > https://bugzilla.redhat.com/show_bug.cgi?id=531916 describes a > system with a _PSC method for the fan that always returns "on". > There's no benefit in us always requesting the state of the fan > when performing transitions - we want to do everything we can > to ensure that the fan turns on when it should do, not risk > hardware damage by believing the hardware when it tells us the > fan is already on. Given that the Leading Other OS(tm) works fine > on this machine, it seems likely that it behaves in much this way. > > Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx> > --- > drivers/acpi/bus.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > Index: linux-2.6/drivers/acpi/bus.c > =================================================================== > --- linux-2.6.orig/drivers/acpi/bus.c > +++ linux-2.6/drivers/acpi/bus.c > @@ -190,16 +190,16 @@ int acpi_bus_get_power(acpi_handle handl > * Get the device's power state either directly (via _PSC) or > * indirectly (via power resources). > */ > - if (device->power.flags.explicit_get) { > + if (device->power.flags.power_resources) { > + result = acpi_power_get_inferred_state(device); > + if (result) > + return result; > + } else if (device->power.flags.explicit_get) { > status = acpi_evaluate_integer(device->handle, "_PSC", > NULL, &psc); > if (ACPI_FAILURE(status)) > return -ENODEV; > device->power.state = (int)psc; > - } else if (device->power.flags.power_resources) { > - result = acpi_power_get_inferred_state(device); > - if (result) > - return result; > } > > *state = device->power.state; > > > > -- > 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 > -- 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
