diff mbox series

[2/3] PCI / PM: Decode D3cold power state correctly

Message ID 20190822200551.129039-3-helgaas@kernel.org
State Accepted
Delegated to: Bjorn Helgaas
Headers show
Series PCI: Add PCI_ERROR_RESPONSE, check for errors | expand

Commit Message

Bjorn Helgaas Aug. 22, 2019, 8:05 p.m. UTC 
From: Bjorn Helgaas <bhelgaas@google.com>

Use pci_power_name() to print pci_power_t correctly.  This changes:

  "state 0" or "D0"   to   "D0"
  "state 1" or "D1"   to   "D1"
  "state 2" or "D2"   to   "D2"
  "state 3" or "D3"   to   "D3hot"
  "state 4" or "D4"   to   "D3cold"

Changes dmesg logging only, no other functional change intended.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/pci/pci.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)
diff mbox series

Patch

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index bfc739dc6ada..5f0a3145c3f2 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -834,14 +834,16 @@  static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
 		return -EINVAL;
 
 	/*
-	 * Validate current state:
-	 * Can enter D0 from any state, but if we can only go deeper
-	 * to sleep if we're already in a low power state
+	 * Validate transition: We can enter D0 from any state, but if
+	 * we're already in a low-power state, we can only go deeper.  E.g.,
+	 * we can go from D1 to D3, but we can't go directly from D3 to D1;
+	 * we'd have to go from D3 to D0, then to D1.
 	 */
 	if (state != PCI_D0 && dev->current_state <= PCI_D3cold
 	    && dev->current_state > state) {
-		pci_err(dev, "invalid power transition (from state %d to %d)\n",
-			dev->current_state, state);
+		pci_err(dev, "invalid power transition (from %s to %s)\n",
+			pci_power_name(dev->current_state),
+			pci_power_name(state));
 		return -EINVAL;
 	}
 
@@ -891,8 +893,8 @@  static int pci_raw_set_power_state(struct pci_dev *dev, pci_power_t state)
 	pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
 	dev->current_state = (pmcsr & PCI_PM_CTRL_STATE_MASK);
 	if (dev->current_state != state && printk_ratelimit())
-		pci_info(dev, "Refused to change power state, currently in D%d\n",
-			 dev->current_state);
+		pci_info(dev, "refused to change power state (currently %s)\n",
+			 pci_power_name(dev->current_state));
 
 	/*
 	 * According to section 5.4.1 of the "PCI BUS POWER MANAGEMENT