On Wednesday, January 30, 2013 06:53:46 PM Peter Wu wrote: > Hi Lv Zheng, > > I encounter a regression with your patch (Linux 3.8-rc5). On my Nvidia Optimus > laptop, I use the bbswitch[1] kernel module to trigger a _PS3 ACPI method call > to turn the video card off. > > After this patch, I got the following in my kernel log: > > pci 0000:01:00.0: Refused to change power state, currently in D0 > ACPI: Cannot transition to non-D0 state from D3 > bbswitch: Succesfully loaded. Discrete card 0000:01:00.0 is on > > The expected output would be "Discrete card 0000:01:00.0 is off". Printing the > contents of (acpi_device) device->power.state shows FF (ACPI_STATE_UNKNOWN). > Should this condition be excluded from your check or is my hacky module > outdated? > > I currently workaround this issue by checking for ACPI_STATE_UNKNOWN. If that > is the value, I assume on (overwrite device->power.state with ACPI_STATE_D0). > Then I call pci_set_power_state(pci_dev, PCI_D3cold). You shouldn't ever be transitioning from an uknown state to D3cold directly. Please first transition to D0 and then to D3cold. Can you please test the linux-next branch of the linux-pm.git tree and check if you see this problem in there too? Rafael > [1]: https://github.com/Bumblebee-Project/bbswitch > > On Thursday 15 November 2012 12:25:01 Lv Zheng wrote: > > No power transitioning from D3 state to a non-D0 state is allowed. > > This patch also cleans up device power updating code in the > > acpi_device_set_power() as it should already been updated in the > > acpi_power_transition(). > > > > Signed-off-by: Lv Zheng <lv.zheng@xxxxxxxxx> > > --- > > drivers/acpi/bus.c | 7 ++++++- > > 1 file changed, 6 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c > > index 07a20ee..12c1b51 100644 > > --- a/drivers/acpi/bus.c > > +++ b/drivers/acpi/bus.c > > @@ -293,6 +293,12 @@ int acpi_device_set_power(struct acpi_device *device, > > int state) " state than parent\n"); > > return -ENODEV; > > } > > + if (device->parent->power.state >= ACPI_STATE_D3_HOT && > > + state != ACPI_STATE_D0) { > > + printk(KERN_WARNING PREFIX > > + "Cannot transition to non-D0 state from D3\n"); > > + return -ENODEV; > > + } > > > > /* For D3cold we should execute _PS3, not _PS4. */ > > if (state == ACPI_STATE_D3_COLD) > > @@ -341,7 +347,6 @@ int acpi_device_set_power(struct acpi_device *device, > > int state) "Device [%s] failed to transition to %s\n", > > device->pnp.bus_id, state_string(state)); > > else { > > - device->power.state = state; > > ACPI_DEBUG_PRINT((ACPI_DB_INFO, > > "Device [%s] transitioned to %s\n", > > device->pnp.bus_id, state_string(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 -- I speak only for myself. Rafael J. Wysocki, Intel Open Source Technology Center. -- 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
