[PATCH] bus: mhi: host: pci_generic: Add missing poweroff() PM callback

[PATCH] bus: mhi: host: pci_generic: Add missing poweroff() PM callback

[Manivannan Sadhasivam]

During hibernation process, once thaw() stage completes, the MHI endpoint
devices will be in M0 state post recovery. After that, the devices will be
powered down so that the system can enter the target sleep state. During
this stage, the PCI core will put the devices in D3hot. But this transition
is allowed by the MHI spec. The devices can only enter D3hot when it is in
M3 state.

So for fixing this issue, let's add the poweroff() callback that will get
executed before putting the system in target sleep state during
hibernation. This callback will put the device in M3 state and that would
allow it to receive the D3hot afterwards.

Cc: stable@vger.kernel.org
Fixes: 5f0c2ee1fe8d ("bus: mhi: pci-generic: Fix hibernation")
Reported-by: Hemant Kumar <quic_hemantk@quicinc.com>
Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
---
 drivers/bus/mhi/host/pci_generic.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
index 9527b7d63840..b1c0a8887496 100644
--- a/drivers/bus/mhi/host/pci_generic.c
+++ b/drivers/bus/mhi/host/pci_generic.c
@@ -1085,6 +1085,7 @@ static const struct dev_pm_ops mhi_pci_pm_ops = {
 	.resume = mhi_pci_resume,
 	.freeze = mhi_pci_freeze,
 	.thaw = mhi_pci_restore,
+	.poweroff = mhi_pci_suspend,
 	.restore = mhi_pci_restore,
 #endif
 };
-- 
2.25.1

Re: [PATCH] bus: mhi: host: pci_generic: Add missing poweroff() PM callback

[Loic Poulain]

On Mon, 4 Apr 2022 at 08:41, Manivannan Sadhasivam
<manivannan.sadhasivam@linaro.org> wrote:
>
> During hibernation process, once thaw() stage completes, the MHI endpoint
> devices will be in M0 state post recovery. After that, the devices will be
> powered down so that the system can enter the target sleep state. During
> this stage, the PCI core will put the devices in D3hot. But this transition
> is allowed by the MHI spec. The devices can only enter D3hot when it is in
> M3 state.
>
> So for fixing this issue, let's add the poweroff() callback that will get
> executed before putting the system in target sleep state during
> hibernation. This callback will put the device in M3 state and that would
> allow it to receive the D3hot afterwards.
>
> Cc: stable@vger.kernel.org
> Fixes: 5f0c2ee1fe8d ("bus: mhi: pci-generic: Fix hibernation")
> Reported-by: Hemant Kumar <quic_hemantk@quicinc.com>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>

Reviewed-by: Loic Poulain <loic.poulain@linaro.org>


> ---
>  drivers/bus/mhi/host/pci_generic.c | 1 +
>  1 file changed, 1 insertion(+)
>
> diff --git a/drivers/bus/mhi/host/pci_generic.c b/drivers/bus/mhi/host/pci_generic.c
> index 9527b7d63840..b1c0a8887496 100644
> --- a/drivers/bus/mhi/host/pci_generic.c
> +++ b/drivers/bus/mhi/host/pci_generic.c
> @@ -1085,6 +1085,7 @@ static const struct dev_pm_ops mhi_pci_pm_ops = {
>         .resume = mhi_pci_resume,
>         .freeze = mhi_pci_freeze,
>         .thaw = mhi_pci_restore,
> +       .poweroff = mhi_pci_suspend,
>         .restore = mhi_pci_restore,
>  #endif
>  };
> --
> 2.25.1
>