PCI PM: Use pci_set_power_state during early resume

Once we have allowed timer interrupts to be enabled during the early
phase of resuming devices, we are now able to use the generic
pci_set_power_state() to put PCI devices into D0 at that time.  Then,
the platform-specific PM code will have a chance to handle devices
that don't implement the native PCI PM or that require some
additional, platform-specific operations to be carried out to power
them up.  Also, by doing this we can simplify the code quite a bit.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Jesse Barnes <jbarnes@virtuousgeek.org>

1 files changed, 9 insertions, 39 deletions

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 6d6120007af4..3acb1da296d5 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -426,7 +426,6 @@ static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
  *                           given PCI device
  * @dev: PCI device to handle.
  * @state: PCI power state (D0, D1, D2, D3hot) to put the device into.
- * @wait: If 'true', wait for the device to change its power state
  *
  * RETURN VALUE:
  * -EINVAL if the requested state is invalid.
@@ -435,8 +434,7 @@ static inline int platform_pci_sleep_wake(struct pci_dev *dev, bool enable)
  * 0 if device already is in the requested state.
  * 0 if device's power state has been successfully changed.
  */
-static int
-pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state, bool wait)
+static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
 {
         u16 pmcsr;
         bool need_restore = false;
@@ -481,10 +479,8 @@ pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state, bool wait)
                 break;
         case PCI_UNKNOWN: /* Boot-up */
                 if ((pmcsr & PCI_PM_CTRL_STATE_MASK) == PCI_D3hot
-                 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET)) {
+                 && !(pmcsr & PCI_PM_CTRL_NO_SOFT_RESET))
                         need_restore = true;
-                        wait = true;
-                }
                 /* Fall-through: force to D0 */
         default:
                 pmcsr = 0;
@@ -494,9 +490,6 @@ pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state, bool wait)
         /* enter specified state */
         pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
 
-        if (!wait)
-                return 0;
-
         /* Mandatory power management transition delays */
         /* see PCI PM 1.1 5.6.1 table 18 */
         if (state == PCI_D3hot || dev->current_state == PCI_D3hot)
@@ -521,7 +514,7 @@ pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state, bool wait)
         if (need_restore)
                 pci_restore_bars(dev);
 
-        if (wait && dev->bus->self)
+        if (dev->bus->self)
                 pcie_aspm_pm_state_change(dev->bus->self);
 
         return 0;
@@ -591,7 +584,7 @@ int pci_set_power_state(struct pci_dev *dev, pci_power_t state)
         if (state == PCI_D3hot && (dev->dev_flags & PCI_DEV_FLAGS_NO_D3))
                 return 0;
 
-        error = pci_raw_set_power_state(dev, state, true);
+        error = pci_raw_set_power_state(dev, state);
 
         if (state > PCI_D0 && platform_pci_power_manageable(dev)) {
                 /* Allow the platform to finalize the transition */
@@ -1390,37 +1383,14 @@ void pci_allocate_cap_save_buffers(struct pci_dev *dev)
  */
 int pci_restore_standard_config(struct pci_dev *dev)
 {
-        pci_power_t prev_state;
-        int error;
-
-        pci_update_current_state(dev, PCI_D0);
-
-        prev_state = dev->current_state;
-        if (prev_state == PCI_D0)
-                goto Restore;
-
-        error = pci_raw_set_power_state(dev, PCI_D0, false);
-        if (error)
-                return error;
+        pci_update_current_state(dev, PCI_UNKNOWN);
 
-        /*
-         * This assumes that we won't get a bus in B2 or B3 from the BIOS, but
-         * we've made this assumption forever and it appears to be universally
-         * satisfied.
-         */
-        switch(prev_state) {
-        case PCI_D3cold:
-        case PCI_D3hot:
-                mdelay(pci_pm_d3_delay);
-                break;
-        case PCI_D2:
-                udelay(PCI_PM_D2_DELAY);
-                break;
+        if (dev->current_state != PCI_D0) {
+                int error = pci_set_power_state(dev, PCI_D0);
+                if (error)
+                        return error;
         }
 
-        pci_update_current_state(dev, PCI_D0);
-
- Restore:
         return dev->state_saved ? pci_restore_state(dev) : 0;
 }