> -----Original Message----- > From: Rob Herring [mailto:r...@kernel.org] > Sent: 2016年6月3日 9:54 > To: Yang, Wenyou <wenyou.y...@atmel.com> > Cc: Alan Stern <st...@rowland.harvard.edu>; Greg Kroah-Hartman > <gre...@linuxfoundation.org>; Ferre, Nicolas <nicolas.fe...@atmel.com>; > Pawel Moll <pawel.m...@arm.com>; Mark Brown <broo...@kernel.org>; Ian > Campbell <ijc+devicet...@hellion.org.uk>; Kumar Gala <ga...@codeaurora.org>; > Alexandre Belloni <alexandre.bell...@free-electrons.com>; linux- > ker...@vger.kernel.org; devicet...@vger.kernel.org; linux-arm- > ker...@lists.infradead.org; linux-usb@vger.kernel.org > Subject: Re: [PATCH v2 1/2] usb: ohci-at91: Forcibly suspend ports while USB > suspend > > On Wed, Jun 01, 2016 at 12:29:59PM +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.y...@atmel.com> > > --- > > > > 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 | 5 +- > > drivers/usb/host/ohci-at91.c | 80 > > +++++++++++++++++++++- > > include/soc/at91/at91_sfr.h | 29 ++++++++ > > 3 files changed, 111 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..3e3e58a 100644 > > --- a/Documentation/devicetree/bindings/usb/atmel-usb.txt > > +++ b/Documentation/devicetree/bindings/usb/atmel-usb.txt > > @@ -3,8 +3,9 @@ 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 SAMA5D2 which can force to suspend. > > That may be why you need this now, but that is irrelevant to having a chip > specific > compatible string.
Maybe a property is better. Best Regards, Wenyou Yang
