PCI: Document connection between pci_power_t and hardware PM capability
The dev.pme_support field, pci_pm_init(), pci_pme_capable(), and
pci_raw_set_power_state() depend on the fact that the pci_power_t values
(PCI_D0, PCI_D1, etc.) match the definition of the Capabilities PME_Support
and the Control/Status PowerState fields in the Power Management capability
(see PCI Bus Power Management spec r1.2, sec 3.2.3).
Add a note to this effect at the pci_power_t typedef.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 8597b42..0a1a9e3 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -101,6 +101,10 @@
DEVICE_COUNT_RESOURCE = PCI_NUM_RESOURCES,
};
+/*
+ * pci_power_t values must match the bits in the Capabilities PME_Support
+ * and Control/Status PowerState fields in the Power Management capability.
+ */
typedef int __bitwise pci_power_t;
#define PCI_D0 ((pci_power_t __force) 0)