[PATCH v1 02/11] PCI/PM: Relocate pci_set_low_power_state()

Rafael J. Wysocki
2022-05-05T18:29:04Z

Because pci_set_power_state() is the only caller of
pci_set_low_power_state(), put the latter next to the former.

No functional impact.

Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
drivers/pci/pci.c | 158 +++++++++++++++++++++++++++---------------------------
1 file changed, 79 insertions(+), 79 deletions(-)

Index: linux-pm/drivers/pci/pci.c
===================================================================
--- linux-pm.orig/drivers/pci/pci.c
+++ linux-pm/drivers/pci/pci.c
@@ -1068,85 +1068,6 @@ static inline bool platform_pci_bridge_d
}

/**
- * pci_set_low_power_state - Put a PCI device into a low-power state.
- * @dev: PCI device to handle.
- * @state: PCI power state (D1, D2, D3hot) to put the device into.
- *
- * Use the device's PCI_PM_CTRL register to put it into a low-power state.
- *
- * RETURN VALUE:
- * -EINVAL if the requested state is invalid.
- * -EIO if device does not support PCI PM or its PM capabilities register has a
- * wrong version, or device doesn't support the requested state.
- * 0 if device already is in the requested state.
- * 0 if device's power state has been successfully changed.
- */
-static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state)
-{
- u16 pmcsr;
-
- /* Check if we're already there */
- if (dev->current_state == state)
- return 0;
-
- if (!dev->pm_cap)
- return -EIO;
-
- if (state < PCI_D1 || state > PCI_D3hot)
- return -EINVAL;
-
- /*
- * 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 (dev->current_state <= PCI_D3cold && 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;
- }
-
- /* Check if this device supports the desired state */
- if ((state == PCI_D1 && !dev->d1_support)
- || (state == PCI_D2 && !dev->d2_support))
- return -EIO;
-
- pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
- if (PCI_POSSIBLE_ERROR(pmcsr)) {
- pci_err(dev, "Unable to change power state from %s to %s, device inaccessible\n",
- pci_power_name(dev->current_state),
- pci_power_name(state));
- return -EIO;
- }
-
- pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
- pmcsr |= state;
-
- /* Enter specified state */
- pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
-
- /* Mandatory power management transition delays; see PCI PM 1.2. */
- if (state == PCI_D3hot)
- pci_dev_d3_sleep(dev);
- else if (state == PCI_D2)
- udelay(PCI_PM_D2_DELAY);
-
- 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)
- pci_info_ratelimited(dev, "Refused to change power state from %s to %s\n",
- pci_power_name(dev->current_state),
- pci_power_name(state));
-
- if (dev->bus->self)
- pcie_aspm_pm_state_change(dev->bus->self);
-
- return 0;
-}
-
-/**
* pci_update_current_state - Read power state of given device and cache it
* @dev: PCI device to handle.
* @state: State to cache in case the device doesn't have the PM capability
@@ -1364,6 +1285,85 @@ void pci_bus_set_current_state(struct pc
}

/**
+ * pci_set_low_power_state - Put a PCI device into a low-power state.
+ * @dev: PCI device to handle.
+ * @state: PCI power state (D1, D2, D3hot) to put the device into.
+ *
+ * Use the device's PCI_PM_CTRL register to put it into a low-power state.
+ *
+ * RETURN VALUE:
+ * -EINVAL if the requested state is invalid.
+ * -EIO if device does not support PCI PM or its PM capabilities register has a
+ * wrong version, or device doesn't support the requested state.
+ * 0 if device already is in the requested state.
+ * 0 if device's power state has been successfully changed.
+ */
+static int pci_set_low_power_state(struct pci_dev *dev, pci_power_t state)
+{
+ u16 pmcsr;
+
+ /* Check if we're already there */
+ if (dev->current_state == state)
+ return 0;
+
+ if (!dev->pm_cap)
+ return -EIO;
+
+ if (state < PCI_D1 || state > PCI_D3hot)
+ return -EINVAL;
+
+ /*
+ * 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 (dev->current_state <= PCI_D3cold && 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;
+ }
+
+ /* Check if this device supports the desired state */
+ if ((state == PCI_D1 && !dev->d1_support)
+ || (state == PCI_D2 && !dev->d2_support))
+ return -EIO;
+
+ pci_read_config_word(dev, dev->pm_cap + PCI_PM_CTRL, &pmcsr);
+ if (PCI_POSSIBLE_ERROR(pmcsr)) {
+ pci_err(dev, "Unable to change power state from %s to %s, device inaccessible\n",
+ pci_power_name(dev->current_state),
+ pci_power_name(state));
+ return -EIO;
+ }
+
+ pmcsr &= ~PCI_PM_CTRL_STATE_MASK;
+ pmcsr |= state;
+
+ /* Enter specified state */
+ pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, pmcsr);
+
+ /* Mandatory power management transition delays; see PCI PM 1.2. */
+ if (state == PCI_D3hot)
+ pci_dev_d3_sleep(dev);
+ else if (state == PCI_D2)
+ udelay(PCI_PM_D2_DELAY);
+
+ 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)
+ pci_info_ratelimited(dev, "Refused to change power state from %s to %s\n",
+ pci_power_name(dev->current_state),
+ pci_power_name(state));
+
+ if (dev->bus->self)
+ pcie_aspm_pm_state_change(dev->bus->self);
+
+ return 0;
+}
+
+/**
* pci_set_power_state - Set the power state of a PCI device
* @dev: PCI device to handle.
* @state: PCI power state (D0, D1, D2, D3hot) to put the device into.