EM120 not correctly booting up, unknown wwan control port exposed?

[Carl Yin(殷张成)]

Hi Aleksander:
	Do you test PM suspend or Runtime Suspend?
	MHI/PCIE PM suspend is not support by your PC, must use Lenovo laptop.

Regards,
Carl Yin

On Sun, 23 May 2021 at 21:58, Aleksander Morgado <aleksander at aleksander.es> wrote:
>
> Hey,
>
> > >
> > > I wanted to test the EM120 setup I have with latest MM git master 
> > > and kernel 5.13.0-rc2, but unfortunately there is some issue, not 
> > > sure if in device or in kernel driver. These are the kernel logs I 
> > > get as output when the issue happens:
> > >
> > > [  263.458712] mhi-pci-generic 0000:01:00.0: can't change power 
> > > state from D3cold to D0 (config space inaccessible) [  263.458727] 
> > > mhi-pci-generic 0000:01:00.0: can't change power state from D3cold 
> > > to D0 (config space inaccessible) [  263.458736] mhi-pci-generic 
> > > 0000:01:00.0: failed to resume device: -22
> >
> > The problem seems to be with the runtime power management. MHI pci 
> > driver is moving the device in low power state (suspend) when not 
> > used for ~2s. And here device resume fails. How the EM120 is 
> > connected to your machine is it via M2 laptop port or are you using a 'dev-board'
> > with PCI-express slot? can you share the firmware version? building 
> > mainline right now and going to test that on my side.

It works correctly on my side.

> >
>
> This is with a EM120 devkit in a PCI-express slot in my desktop PC, 
> running firmware EM120RGLAPR02A07.

Ok mine is EM120RGLAPR02A07M4G (from --query-device-caps output).

Maybe the suspend issue is due to the devkit. But better to confirm with Carl.

> I tested this setup some months ago with the "mhi_uci_q" driver from 
> Quectel, and I didn't see any problem like this.

Runtime PM was probably not enabled/implemented. For now, maybe apply `ATTR{power/control}="on"` for this device, which should prevent dynamic runtime PM.

Regards,
Loic

>
>
> --
> Aleksander
> https://aleksander.es