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| author | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2022-05-05 20:16:50 +0200 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2022-05-05 14:19:49 -0500 |
| commit | 3cc2a2b2704f76702cdd417573a934502254276d (patch) | |
| tree | 7b0834da3639bc43e1ad6ebd84ae355a3f2342ee /drivers/pci | |
| parent | 0aacdc957401802bd2b94141a3d2c5f88c529e30 (diff) | |
| download | linux-stable-3cc2a2b2704f76702cdd417573a934502254276d.tar.gz linux-stable-3cc2a2b2704f76702cdd417573a934502254276d.tar.bz2 linux-stable-3cc2a2b2704f76702cdd417573a934502254276d.zip | |
PCI/PM: Rearrange pci_set_power_state()
The part of pci_set_power_state() related to transitions into
low-power states is unnecessary convoluted, so clearly divide it
into the D3cold special case and the general case covering all of
the other states.
Also fix a potential issue with calling pci_bus_set_current_state()
to set the current state of all devices on the subordinate bus to
D3cold without checking if the power state of the parent bridge has
really changed to D3cold.
Link: https://lore.kernel.org/r/2139440.Mh6RI2rZIc@kreacher
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/pci.c | 28 |
1 files changed, 17 insertions, 11 deletions
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b6ad2fa354f1..df886098bd60 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1446,19 +1446,25 @@ 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; - /* - * To put device in D3cold, we put device into D3hot in native - * way, then put device into D3cold with platform ops - */ - error = pci_set_low_power_state(dev, state > PCI_D3hot ? - PCI_D3hot : state); + if (state == PCI_D3cold) { + /* + * To put the device in D3cold, put it into D3hot in the native + * way, then put it into D3cold using platform ops. + */ + error = pci_set_low_power_state(dev, PCI_D3hot); - if (pci_platform_power_transition(dev, state)) - return error; + if (pci_platform_power_transition(dev, PCI_D3cold)) + return error; - /* Powering off a bridge may power off the whole hierarchy */ - if (state == PCI_D3cold) - pci_bus_set_current_state(dev->subordinate, PCI_D3cold); + /* Powering off a bridge may power off the whole hierarchy */ + if (dev->current_state == PCI_D3cold) + pci_bus_set_current_state(dev->subordinate, PCI_D3cold); + } else { + error = pci_set_low_power_state(dev, state); + + if (pci_platform_power_transition(dev, state)) + return error; + } return 0; } |