Re: [PATCH v1] usb: dwc3: add device put function to decrement the ref-counted reference

From: Thinh Nguyen
Date: Fri Nov 10 2023 - 17:54:17 EST


On Fri, Nov 10, 2023, Stanley Chang[昌育德] wrote:
>
>
> > -----Original Message-----
> > From: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>
> > Sent: Friday, November 10, 2023 10:34 AM
> > To: Stanley Chang[昌育德] <stanley_chang@xxxxxxxxxxx>
> > Cc: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>; Christophe JAILLET
> > <christophe.jaillet@xxxxxxxxxx>; Greg Kroah-Hartman
> > <gregkh@xxxxxxxxxxxxxxxxxxx>; linux-usb@xxxxxxxxxxxxxxx;
> > linux-kernel@xxxxxxxxxxxxxxx
> > Subject: Re: [PATCH v1] usb: dwc3: add device put function to decrement the
> > ref-counted reference
> >
> >
> > External mail.
> >
> >
> >
> > On Tue, Nov 07, 2023, Stanley Chang wrote:
> > > When the function exits, the count should be decremented via
> > > platform_device_put and of_node_put.
> > >
> > > Fixes: 34c200483569 ("usb: dwc3: add Realtek DHC RTD SoC dwc3 glue
> > > layer driver")
> > > Signed-off-by: Stanley Chang <stanley_chang@xxxxxxxxxxx>
> > > ---
> > > drivers/usb/dwc3/dwc3-rtk.c | 3 +++
> > > 1 file changed, 3 insertions(+)
> > >
> > > diff --git a/drivers/usb/dwc3/dwc3-rtk.c b/drivers/usb/dwc3/dwc3-rtk.c
> > > index 590028e8fdcb..9d6f2a8bd6ce 100644
> > > --- a/drivers/usb/dwc3/dwc3-rtk.c
> > > +++ b/drivers/usb/dwc3/dwc3-rtk.c
> > > @@ -187,6 +187,7 @@ static enum usb_device_speed
> > > __get_dwc3_maximum_speed(struct device_node *np)
> > >
> > > ret = match_string(speed_names, ARRAY_SIZE(speed_names),
> > > maximum_speed);
> > >
> > > + of_node_put(dwc3_np);
> > > return (ret < 0) ? USB_SPEED_UNKNOWN : ret; }
> > >
> > > @@ -339,6 +340,8 @@ static int dwc3_rtk_probe_dwc3_core(struct
> > > dwc3_rtk *rtk)
> > >
> > > switch_usb2_role(rtk, rtk->cur_role);
> > >
> > > + platform_device_put(dwc3_pdev);
> >
> > Don't you use this after probe? Why put here and not on remove?
>
> I don't use dwc3_pdev in driver.
> I use rtk->dwc and dwc is removed by of_platform_depopulate on remove.
> So I think I don't need to keep the count of dwc3_pdev.
>

Thanks for the clarification.

Acked-by: Thinh Nguyen <Thinh.Nguyen@xxxxxxxxxxxx>

BR,
Thinh