Re: [PATCH 0/3] USB IMX Chipidea fix gpio vbus control

[Marco Felsch <m.felsch@pengutronix.de>]

Hi Peter,

On 20-02-28 02:51, Peter Chen wrote:

...

> > > CI_HDRC_TURN_VBUS_EARLY_ON is introduced by fixing a bug that some i.mx USB
> > > controllers PHY's power is sourced from VBUS, the PHY's power need to be on before
> > > touch some ehci registers, otherwise, the USB signal will be wrong at some low speed
> > > devices use case. So, this flag can't be deleted, it may cause regression.
> > 
> > Pls check my archeological findings and again pls check my patches. I
> > deleted the flag because isn't required anymore afterwards.
> 
> I have already checked your patch, your patch deletes CI_HDRC_TURN_VBUS_EARLY_ON
> quirk, and it may cause regression.

Arg, sorry now I see what you mean. Thanks for your explanation :)
Since the 'struct ehci_ci_priv' contains now an enabled state we can
git rid of the flag. To get it right, the writing the ehci PORT_POWER
must be done before or after we enabled the VBUS? I'm asking because
we can drop the 1st patch of this series.

> > > The solution I see is your may need to implement chipidea VBUS control flow by considering
> > > pm_qos_no_power_off at suspend situation. You may add .suspend API for ci_role_driver,
> > > and called by ci_controller_suspend/ci_controller_resume, of cos, better solution is welcome.
> > 
> > I fixed it within the core [1] and here at the chipidea side.
> > 
> > [1] https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flkml.org%2Flkml%2F2020%2F2%2F27%2F669&data=02%7C01%7Cpeter.chen%40nxp.com%7Cad9b3833ae2f433d93ef08d7bb92d4a0%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%7C0%7C637184111614326500&sdata=SPwwBEGBco6IdP8ufmAnJeeRxuAXGLa0xzYlzFA%2FAvg%3D&reserved=0
> > 
> > You will never enter the ehci_ci_portpower() during suspend without [1]
> > if you are using a vanilla kernel. So IMHO this case can't be tested,
> > sorry.
> > 
> 
> Through set pm_qos_no_power_off as 0, the VBUS will be off. You
> never need to call .ehci_ci_portpower again. You may try my second
> suggestion for fix chipidea issue. I will reply your RFC patch for
> USB core.

Many thanks for testing =)

Regards,
  Marco

> -- 
> 
> Thanks,
> Peter Chen