[PATCH] suspend: PCI power managment reference implementation
Added reference implementation of suspend and resume routines.
From: Shaohua Li <shaohua.li@intel.com>
build fix
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/Documentation/power/pci.txt b/Documentation/power/pci.txt
index 35b1a7d..6fc9d51 100644
--- a/Documentation/power/pci.txt
+++ b/Documentation/power/pci.txt
@@ -291,6 +291,44 @@
pci_enable_wake (one for both D3hot and D3cold).
+A reference implementation
+-------------------------
+.suspend()
+{
+ /* driver specific operations */
+
+ /* Disable IRQ */
+ free_irq();
+ /* If using MSI */
+ pci_disable_msi();
+
+ pci_save_state();
+ pci_enable_wake();
+ /* Disable IO/bus master/irq router */
+ pci_disable_device();
+ pci_set_power_state(pci_choose_state());
+}
+
+.resume()
+{
+ pci_set_power_state(PCI_D0);
+ pci_restore_state();
+ /* device's irq possibly is changed, driver should take care */
+ pci_enable_device();
+ pci_set_master();
+
+ /* if using MSI, device's vector possibly is changed */
+ pci_enable_msi();
+
+ request_irq();
+ /* driver specific operations; */
+}
+
+This is a typical implementation. Drivers can slightly change the order
+of the operations in the implementation, ignore some operations or add
+more deriver specific operations in it, but drivers should do something like
+this on the whole.
+
5. Resources
~~~~~~~~~~~~