On Tuesday, August 03, 2010, Kenji Kaneshige wrote: > (2010/08/03 6:53), Rafael J. Wysocki wrote: > > From: Rafael J. Wysocki<rjw@xxxxxxx> > > > > Introduce a function allowing the caller to obtain a mask of _OSC > > control bits the BIOS will allow the kernel to control for a given > > PCI root bridge. > > > > Signed-off-by: Rafael J. Wysocki<rjw@xxxxxxx> > > --- > > drivers/acpi/pci_root.c | 58 ++++++++++++++++++++++++++++++++++++++++-------- > > include/linux/acpi.h | 1 > > 2 files changed, 50 insertions(+), 9 deletions(-) > > > > Index: linux-2.6/drivers/acpi/pci_root.c > > =================================================================== > > --- linux-2.6.orig/drivers/acpi/pci_root.c > > +++ linux-2.6/drivers/acpi/pci_root.c > > @@ -225,21 +225,32 @@ static acpi_status acpi_pci_run_osc(acpi > > return status; > > } > > > > -static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags) > > +static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, > > + u32 support, > > + u32 *control) > > { > > acpi_status status; > > - u32 support_set, result, capbuf[3]; > > + u32 result, capbuf[3]; > > + > > + support&= OSC_PCI_SUPPORT_MASKS; > > + support |= root->osc_support_set; > > > > - /* do _OSC query for all possible controls */ > > - support_set = root->osc_support_set | (flags& OSC_PCI_SUPPORT_MASKS); > > capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE; > > - capbuf[OSC_SUPPORT_TYPE] = support_set; > > - capbuf[OSC_CONTROL_TYPE] = OSC_PCI_CONTROL_MASKS; > > + capbuf[OSC_SUPPORT_TYPE] = support; > > + if (control) { > > + *control&= OSC_PCI_CONTROL_MASKS; > > + capbuf[OSC_CONTROL_TYPE] = *control; > > I think controls that are already granted to OS need to be ORed here. > I.e. > > capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | *control; That's correct. 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