The algorithm to update the flag indicating whether a bridge may go to
D3 makes a few optimizations based on whether the update was caused by
the removal of a device on the one hand, versus the addition of a device
or the change of its D3cold flags on the other hand.
The information whether the update pertains to a removal is currently
passed in by the caller, but the function may as well determine that
itself by examining the device in question, thereby allowing for a
considerable simplification and reduction of the code.
Out of several options to determine removal, I've chosen the function
device_is_registered() because it's cheap: It merely returns the
dev->kobj.state_in_sysfs flag. That flag is set through device_add()
when the root bus is scanned and cleared through device_remove().
The call to pci_bridge_d3_update() happens after each of these calls,
respectively, so the ordering is correct.
No functional change intended.
Cc: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
---
drivers/pci/bus.c | 2 +-
drivers/pci/pci.c | 35 +++++------------------------------
drivers/pci/pci.h | 3 +--
drivers/pci/remove.c | 2 +-
4 files changed, 8 insertions(+), 34 deletions(-)
diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c
index c288e5a..bc56cf1 100644
--- a/drivers/pci/bus.c
+++ b/drivers/pci/bus.c
@@ -320,7 +320,7 @@ void pci_bus_add_device(struct pci_dev *dev)
pci_fixup_device(pci_fixup_final, dev);
pci_create_sysfs_dev_files(dev);
pci_proc_attach_device(dev);
- pci_bridge_d3_device_changed(dev);
+ pci_bridge_d3_update(dev);
dev->match_driver = true;
retval = device_attach(&dev->dev);
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 6e0c399..c12fae7 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -2277,14 +2277,14 @@ static int pci_dev_check_d3cold(struct pci_dev *dev, void *data)
/*
* pci_bridge_d3_update - Update bridge D3 capabilities
* @dev: PCI device which is changed
- * @remove: Is the device being removed
*
* Update upstream bridge PM capabilities accordingly depending on if the
* device PM configuration was changed or the device is being removed. The
* change is also propagated upstream.
*/
-static void pci_bridge_d3_update(struct pci_dev *dev, bool remove)
+void pci_bridge_d3_update(struct pci_dev *dev)
{
+ bool remove = !device_is_registered(&dev->dev);
struct pci_dev *bridge;
bool d3cold_ok = true;
@@ -2311,36 +2311,11 @@ static void pci_bridge_d3_update(struct pci_dev *dev, bool remove)
if (bridge->bridge_d3 != d3cold_ok) {
bridge->bridge_d3 = d3cold_ok;
/* Propagate change to upstream bridges */
- pci_bridge_d3_update(bridge, false);
+ pci_bridge_d3_update(bridge);
}
}
/**
- * pci_bridge_d3_device_changed - Update bridge D3 capabilities on change
- * @dev: PCI device that was changed
- *
- * If a device is added or its PM configuration, such as is it allowed to
- * enter D3cold, is changed this function updates upstream bridge PM
- * capabilities accordingly.
- */
-void pci_bridge_d3_device_changed(struct pci_dev *dev)
-{
- pci_bridge_d3_update(dev, false);
-}
-
-/**
- * pci_bridge_d3_device_removed - Update bridge D3 capabilities on remove
- * @dev: PCI device being removed
- *
- * Function updates upstream bridge PM capabilities based on other devices
- * still left on the bus.
- */
-void pci_bridge_d3_device_removed(struct pci_dev *dev)
-{
- pci_bridge_d3_update(dev, true);
-}
-
-/**
* pci_d3cold_enable - Enable D3cold for device
* @dev: PCI device to handle
*
@@ -2352,7 +2327,7 @@ void pci_d3cold_enable(struct pci_dev *dev)
{
if (dev->no_d3cold) {
dev->no_d3cold = false;
- pci_bridge_d3_device_changed(dev);
+ pci_bridge_d3_update(dev);
}
}
EXPORT_SYMBOL_GPL(pci_d3cold_enable);
@@ -2369,7 +2344,7 @@ void pci_d3cold_disable(struct pci_dev *dev)
{
if (!dev->no_d3cold) {
dev->no_d3cold = true;
- pci_bridge_d3_device_changed(dev);
+ pci_bridge_d3_update(dev);
}
}
EXPORT_SYMBOL_GPL(pci_d3cold_disable);
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 4518562..27048bb 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -85,8 +85,7 @@ void pci_pm_init(struct pci_dev *dev);
void pci_ea_init(struct pci_dev *dev);
void pci_allocate_cap_save_buffers(struct pci_dev *dev);
void pci_free_cap_save_buffers(struct pci_dev *dev);
-void pci_bridge_d3_device_changed(struct pci_dev *dev);
-void pci_bridge_d3_device_removed(struct pci_dev *dev);
+void pci_bridge_d3_update(struct pci_dev *dev);
static inline void pci_wakeup_event(struct pci_dev *dev)
{
diff --git a/drivers/pci/remove.c b/drivers/pci/remove.c
index f9357e0..73a03d3 100644
--- a/drivers/pci/remove.c
+++ b/drivers/pci/remove.c
@@ -40,7 +40,7 @@ static void pci_destroy_dev(struct pci_dev *dev)
list_del(&dev->bus_list);
up_write(&pci_bus_sem);
- pci_bridge_d3_device_removed(dev);
+ pci_bridge_d3_update(dev);
pci_free_resources(dev);
put_device(&dev->dev);
}
--
2.9.3
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