Re: [PATCH v3 1/2] usb: ohci-at91: Forcibly suspend ports while USB suspend

Alexandre Belloni
2016-06-08T20:38:15Z

On 08/06/2016 at 15:26:51 -0500, Rob Herring wrote :
> On Wed, Jun 08, 2016 at 12:15:10PM +0800, Wenyou Yang wrote:
> > In order to the save power consumption, as a workaround, suspend
> > forcibly the USB PORTA/B/C via set the SUSPEND_A/B/C bits of OHCI
> > Interrupt Configuration Register in the SFRs while OHCI USB suspend.
> >
> > This suspend operation must be done before the USB clock is disabled,
> > resume after the USB clock is enabled.
> >
> > Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
> > ---
> >
> > Changes in v3:
> > - Change the compatible description for more precise.
> >
> > Changes in v2:
> > - Add compatible to support forcibly suspend the ports.
> > - Add soc/at91/at91_sfr.h to accommodate the defines.
> > - Add error checking for .sfr_regmap.
> > - Remove unnecessary regmap_read() statement.
> >
> > .../devicetree/bindings/usb/atmel-usb.txt | 6 +-
> > drivers/usb/host/ohci-at91.c | 80 +++++++++++++++++++++-
> > include/soc/at91/at91_sfr.h | 29 ++++++++
> > 3 files changed, 112 insertions(+), 3 deletions(-)
> > create mode 100644 include/soc/at91/at91_sfr.h
> >
> > diff --git a/Documentation/devicetree/bindings/usb/atmel-usb.txt b/Documentation/devicetree/bindings/usb/atmel-usb.txt
> > index 5883b73..888deaa 100644
> > --- a/Documentation/devicetree/bindings/usb/atmel-usb.txt
> > +++ b/Documentation/devicetree/bindings/usb/atmel-usb.txt
> > @@ -3,8 +3,10 @@ Atmel SOC USB controllers
> > OHCI
> >
> > Required properties:
> > - - compatible: Should be "atmel,at91rm9200-ohci" for USB controllers
> > - used in host mode.
> > + - compatible: Should be one of the following
> > + "atmel,at91rm9200-ohci" for USB controllers used in host mode.
> > + "atmel,sama5d2-ohci" for USB controllers used in host mode
> > + on SAMA5D2 which can force to suspend.
>
> Guess I wasn't clear enough before. Drop "which can force to suspend".
>

Well, my point is that we don't need a new compatible anyway.

--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering