On Thu, Dec 30, 2021 at 4:12 AM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
>
> [+cc Rafael, in case you have insight about the PCI_D0 question below;
> Vaibhav, since this is related to your generic PM conversions]
>
> On Fri, Dec 24, 2021 at 04:19:13PM +0800, Kai-Heng Feng wrote:
> > pci_pm_suspend_noirq() and pci_pm_resume_noirq() already handle power
> > transition for system-wide suspend and resume, so it's not necessary to
> > do it in the driver.
>
> I see DaveM has already applied this, but it looks good to me, thanks
> for doing this!
>
> One minor question below...
>
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
> > ---
> > drivers/net/wwan/iosm/iosm_ipc_pcie.c | 49 ++-------------------------
> > 1 file changed, 2 insertions(+), 47 deletions(-)
> >
> > diff --git a/drivers/net/wwan/iosm/iosm_ipc_pcie.c b/drivers/net/wwan/iosm/iosm_ipc_pcie.c
> > index 2fe88b8be3481..d73894e2a84ed 100644
> > --- a/drivers/net/wwan/iosm/iosm_ipc_pcie.c
> > +++ b/drivers/net/wwan/iosm/iosm_ipc_pcie.c
> > @@ -363,67 +363,22 @@ static int __maybe_unused ipc_pcie_resume_s2idle(struct iosm_pcie *ipc_pcie)
> >
> > int __maybe_unused ipc_pcie_suspend(struct iosm_pcie *ipc_pcie)
> > {
> > - struct pci_dev *pdev;
> > - int ret;
> > -
> > - pdev = ipc_pcie->pci;
> > -
> > - /* Execute D3 one time. */
> > - if (pdev->current_state != PCI_D0) {
> > - dev_dbg(ipc_pcie->dev, "done for PM=%d", pdev->current_state);
> > - return 0;
> > - }
>
> I don't understand the intent of this early exit, and it's not obvious
> to me that pci_pm_suspend_noirq() bails out early when
> (pdev->current_state != PCI_D0).
Yes, I think this can be removed too. Please let me send v2.
Kai-Heng
>
> > /* The HAL shall ask the shared memory layer whether D3 is allowed. */
> > ipc_imem_pm_suspend(ipc_pcie->imem);
> >
> > - /* Save the PCI configuration space of a device before suspending. */
> > - ret = pci_save_state(pdev);
> > -
> > - if (ret) {
> > - dev_err(ipc_pcie->dev, "pci_save_state error=%d", ret);
> > - return ret;
> > - }
> > -
> > - /* Set the power state of a PCI device.
> > - * Transition a device to a new power state, using the device's PCI PM
> > - * registers.
> > - */
> > - ret = pci_set_power_state(pdev, PCI_D3cold);
> > -
> > - if (ret) {
> > - dev_err(ipc_pcie->dev, "pci_set_power_state error=%d", ret);
> > - return ret;
> > - }
> > -
> > dev_dbg(ipc_pcie->dev, "SUSPEND done");
> > - return ret;
> > + return 0;
> > }
> >
> > int __maybe_unused ipc_pcie_resume(struct iosm_pcie *ipc_pcie)
> > {
> > - int ret;
> > -
> > - /* Set the power state of a PCI device.
> > - * Transition a device to a new power state, using the device's PCI PM
> > - * registers.
> > - */
> > - ret = pci_set_power_state(ipc_pcie->pci, PCI_D0);
> > -
> > - if (ret) {
> > - dev_err(ipc_pcie->dev, "pci_set_power_state error=%d", ret);
> > - return ret;
> > - }
> > -
> > - pci_restore_state(ipc_pcie->pci);
> > -
> > /* The HAL shall inform the shared memory layer that the device is
> > * active.
> > */
> > ipc_imem_pm_resume(ipc_pcie->imem);
> >
> > dev_dbg(ipc_pcie->dev, "RESUME done");
> > - return ret;
> > + return 0;
> > }
> >
> > static int __maybe_unused ipc_pcie_suspend_cb(struct device *dev)
> > --
> > 2.33.1
> >
