[+cc Rafael, Vaibhav] On Fri, Dec 24, 2021 at 04:19:14PM +0800, Kai-Heng Feng wrote: > We are seeing spurious wakeup caused by Intel 7560 WWAN on AMD laptops. > This prevent those laptops to stay in s2idle state. > > From what I can understand, the intention of ipc_pcie_suspend() is to > put the device to D3cold, and ipc_pcie_suspend_s2idle() is to keep the > device at D0. However, the device can still be put to D3hot/D3cold by > PCI core. > > So explicitly let PCI core know this device should stay at D0, to solve > the spurious wakeup. > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > --- > drivers/net/wwan/iosm/iosm_ipc_pcie.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/net/wwan/iosm/iosm_ipc_pcie.c b/drivers/net/wwan/iosm/iosm_ipc_pcie.c > index d73894e2a84ed..af1d0e837fe99 100644 > --- a/drivers/net/wwan/iosm/iosm_ipc_pcie.c > +++ b/drivers/net/wwan/iosm/iosm_ipc_pcie.c > @@ -340,6 +340,9 @@ static int __maybe_unused ipc_pcie_suspend_s2idle(struct iosm_pcie *ipc_pcie) > > ipc_imem_pm_s2idle_sleep(ipc_pcie->imem, true); > > + /* Let PCI core know this device should stay at D0 */ > + pci_save_state(ipc_pcie->pci); This is a weird and non-obvious way to say "this device should stay at D0". It's also fairly expensive since pci_save_state() does a lot of slow PCI config reads. > return 0; > } > > -- > 2.33.1 >
