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Subject[PATCH v3 3/9] PCI/PM: Rearrange pci_update_current_state()
Date
From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Save one config space access in pci_update_current_state() by
testing the retireved PCI_PM_CTRL register value against
PCI_POSSIBLE_ERROR() instead of invoking pci_device_is_present()
separately.

While at it, drop a pair of unnecessary parens.

No expected functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

v1 -> v3:
* Fixed typo in the changelog ("retrieved" spelling).
* Added R-by from Mika.

---
drivers/pci/pci.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)

Index: linux-pm/drivers/pci/pci.c
===================================================================
--- linux-pm.orig/drivers/pci/pci.c
+++ linux-pm/drivers/pci/pci.c
@@ -1201,14 +1201,17 @@ static int pci_raw_set_power_state(struc
*/
void pci_update_current_state(struct pci_dev *dev, pci_power_t state)
{
- if (platform_pci_get_power_state(dev) == PCI_D3cold ||
- !pci_device_is_present(dev)) {
+ if (platform_pci_get_power_state(dev) == PCI_D3cold) {
dev->current_state = PCI_D3cold;
} else if (dev->pm_cap) {
u16 pmcsr;

pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
- dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
+ if (PCI_POSSIBLE_ERROR(pmcsr)) {
+ dev->current_state = PCI_D3cold;
+ return;
+ }
+ dev->current_state = pmcsr & PCI_PM_CTRL_STATE_MASK;
} else {
dev->current_state = state;
}


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