[PATCH v1 4/5] PCI: PM: Make pci_choose_state() call pci_target_state()

From: Rafael J. Wysocki
Date: Sat Sep 18 2021 - 09:29:38 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

The pci_choose_state() and pci_target_state() implementations are
somewhat divergent without a good reason, because they are used
for similar purposes.

Change the pci_choose_state() implementation to use pci_target_state()
internally except for transitions to the working state of the system
in which case it is expected to return D0.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/pci/pci-acpi.c | 3 --
drivers/pci/pci.c | 54 ++++++++++++++-----------------------------------
2 files changed, 16 insertions(+), 41 deletions(-)

Index: linux-pm/drivers/pci/pci.c
===================================================================
--- linux-pm.orig/drivers/pci/pci.c
+++ linux-pm/drivers/pci/pci.c
@@ -1331,44 +1331,6 @@ int pci_set_power_state(struct pci_dev *
}
EXPORT_SYMBOL(pci_set_power_state);

-/**
- * pci_choose_state - Choose the power state of a PCI device
- * @dev: PCI device to be suspended
- * @state: target sleep state for the whole system. This is the value
- * that is passed to suspend() function.
- *
- * Returns PCI power state suitable for given device and given system
- * message.
- */
-pci_power_t pci_choose_state(struct pci_dev *dev, pm_message_t state)
-{
- pci_power_t ret;
-
- if (!dev->pm_cap)
- return PCI_D0;
-
- ret = acpi_pci_choose_state(dev);
- if (ret != PCI_POWER_ERROR)
- return ret;
-
- switch (state.event) {
- case PM_EVENT_ON:
- return PCI_D0;
- case PM_EVENT_FREEZE:
- case PM_EVENT_PRETHAW:
- /* REVISIT both freeze and pre-thaw "should" use D0 */
- case PM_EVENT_SUSPEND:
- case PM_EVENT_HIBERNATE:
- return PCI_D3hot;
- default:
- pci_info(dev, "unrecognized suspend event %d\n",
- state.event);
- BUG();
- }
- return PCI_D0;
-}
-EXPORT_SYMBOL(pci_choose_state);
-
#define PCI_EXP_SAVE_REGS 7

static struct pci_cap_saved_state *_pci_find_saved_cap(struct pci_dev *pci_dev,
@@ -2782,6 +2744,22 @@ void pci_dev_complete_resume(struct pci_
spin_unlock_irq(&dev->power.lock);
}

+/**
+ * pci_choose_state - Choose the power state for a PCI device.
+ * @pci_dev: Target PCI device.
+ * @state: Target state for the whole system.
+ *
+ * Returns PCI power state suitable for @pci_dev and @state.
+ */
+pci_power_t pci_choose_state(struct pci_dev *pci_dev, pm_message_t state)
+{
+ if (state.event == PM_EVENT_ON)
+ return PCI_D0;
+
+ return pci_target_state(pci_dev, device_may_wakeup(&pci_dev->dev));
+}
+EXPORT_SYMBOL(pci_choose_state);
+
void pci_config_pm_runtime_get(struct pci_dev *pdev)
{
struct device *dev = &pdev->dev;
Index: linux-pm/drivers/pci/pci-acpi.c
===================================================================
--- linux-pm.orig/drivers/pci/pci-acpi.c
+++ linux-pm/drivers/pci/pci-acpi.c
@@ -910,9 +910,6 @@ pci_power_t acpi_pci_choose_state(struct
{
int acpi_state, d_max;

- if (acpi_pci_disabled)
- return PCI_POWER_ERROR;
-
if (pdev->no_d3cold)
d_max = ACPI_STATE_D3_HOT;
else