On Tue, Aug 13, 2024, Frank Li wrote:
> On Fri, Aug 09, 2024 at 11:18:53PM +0000, Thinh Nguyen wrote:
> > On Fri, Aug 09, 2024, Frank Li wrote:
> > > On Wed, Aug 07, 2024 at 01:13:52AM +0000, Thinh Nguyen wrote:
> > > > On Fri, Jul 12, 2024, Frank Li wrote:
> > > > > From: Li Jun <jun.li@xxxxxxx>
> > > > >
> > > > > The runtime resume will happen before system resume if system wakeup by
> > > > > device mode wakeup event(e.g, VBUS). Add a flag to avoid init twice.
> > > >
> > > > What's the consequence of going through the resuming sequence twice?
> > > > Will this cause any functional issue?
> > >
> > > static int dwc3_core_init_for_resume(struct dwc3 *dwc)
> > > {
> > >
> > > ...
> > > ret = dwc3_clk_enable(dwc);
> > > if (ret)
> > > goto assert_reset;
> > >
> > > ...
> > > }
> > >
> > > clk will be enabled twice, the reference count in clk will be wrong because
> > > clk_disable() only once at suspend.
> >
> > Please capture these info in the commit message.
> >
> > >
> > > So clk will be always ON at next suspend.
> > >
> > > Frank Li
> > >
> >
> > dwc3_clk_enable() happens in probe() and dwc3_core_init_for_resume(),
> > but you're checking dwc->core_inited in dwc3_core_init(). Why?
>
> I have not check dwc->core_inited in dwc3_core_init(). Just set init value
> dwc->core_inited = true
>
> Do you means dwc3_core_init() as dwc3_resume_common()?
>
You set the dwc->core_inited in dwc3_core_init(). However, you use this
flag to also check if dwc3_clk_enable() is done. dwc3_clk_enable() is
not done in dwc3_core_init().
> >
> > If the issue is only related to clk_enable(), perhaps just check that?
>
> This should be major one. Any paired operator between suspend/resume should
> have issue.
>
I don't know what else could be a problem in dwc3_core_init(). As far as
I know, it's only dwc3_clk_enable().
I questioned because of the mismatch use of the check, where the issue
you mentioned is outside of dwc3_core_init(). Perhaps the flag should
not be set there. If that's the case, rename the flag to match the check
condition (if necessary).
>
> >
> > (minor nit: rename core_inited to core_initialized if you plan to do
> > that)
> >
> > Thanks,
> > Thinh
> >
> > > > >
> > > > > Reviewed-by: Peter Chen <peter.chen@xxxxxxx>
> > > > > Signed-off-by: Li Jun <jun.li@xxxxxxx>
> > > > > Signed-off-by: Frank Li <Frank.Li@xxxxxxx>
> > > > > ---
> > > > > drivers/usb/dwc3/core.c | 13 +++++++++++++
> > > > > drivers/usb/dwc3/core.h | 1 +
> > > > > 2 files changed, 14 insertions(+)
> > > > >
> > > > > diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
> > > > > index 734de2a8bd212..d60917fad8c52 100644
> > > > > --- a/drivers/usb/dwc3/core.c
> > > > > +++ b/drivers/usb/dwc3/core.c
> > > > > @@ -950,6 +950,8 @@ static void dwc3_core_exit(struct dwc3 *dwc)
> > > > > dwc3_phy_exit(dwc);
> > > > > dwc3_clk_disable(dwc);
> > > > > reset_control_assert(dwc->reset);
> > > > > +
> > > > > + dwc->core_inited = false;
> > > > > }
> > > > >
> > > > > static bool dwc3_core_is_valid(struct dwc3 *dwc)
> > > > > @@ -1446,6 +1448,8 @@ static int dwc3_core_init(struct dwc3 *dwc)
> > > > > dwc3_writel(dwc->regs, DWC3_LLUCTL, reg);
> > > > > }
> > > > >
> > > > > + dwc->core_inited = true;
> > > > > +
> > > > > return 0;
> > > > >
> > > > > err_power_off_phy:
> > > > > @@ -2375,6 +2379,15 @@ static int dwc3_resume_common(struct dwc3 *dwc, pm_message_t msg)
> > > > >
> > > > > switch (dwc->current_dr_role) {
> > > > > case DWC3_GCTL_PRTCAP_DEVICE:
> > > > > + /*
> > > > > + * system resume may come after runtime resume
> > > > > + * e.g. rpm suspend -> pm suspend -> wakeup
> > > > > + * -> rpm resume -> system resume, so if already
> > > > > + * runtime resumed, system resume should skip it.
> > > > > + */
> > > > > + if (dwc->core_inited)
> > > > > + break;
> > > > > +
> > > > > ret = dwc3_core_init_for_resume(dwc);
> > > > > if (ret)
> > > > > return ret;
> > > > > diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
> > > > > index 1e561fd8b86e2..8a4bfd9a25b19 100644
> > > > > --- a/drivers/usb/dwc3/core.h
> > > > > +++ b/drivers/usb/dwc3/core.h
> > > > > @@ -1195,6 +1195,7 @@ struct dwc3 {
> > > > > struct clk *utmi_clk;
> > > > > struct clk *pipe_clk;
> > > > >
> > > > > + bool core_inited;
Document new member of the struct.
> > > > > struct reset_control *reset;
> > > > >
> > > > > struct usb_phy *usb2_phy;
> > > > >
> > > > > --
> > > > > 2.34.1
> > > > >
Thanks,
Thinh
