From: Pavel Machek <pavel@ucw.cz>
Added reference implementation of suspend and resume routines.
From: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Pavel Machek <pavel@suse.cz>
Signed-off-by: Andrew Morton <akpm@osdl.org>
---
Documentation/power/pci.txt | 38 ++++++++++++++++++++++++++++++++++++++
1 files changed, 38 insertions(+)
diff -puN Documentation/power/pci.txt~suspend-pci-power-managment-reference-implementation Documentation/power/pci.txt
--- 25/Documentation/power/pci.txt~suspend-pci-power-managment-reference-implementation Fri May 27 16:08:04 2005
+++ 25-akpm/Documentation/power/pci.txt Fri May 27 16:08:04 2005
@@ -291,6 +291,44 @@ a request to enable wake events from D3,
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
~~~~~~~~~~~~
_