Re: [PATCH 3/4] usb: Introduce DesignWare USB3 DRD Driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi,

On Thu, Aug 25, 2011 at 01:48:09PM -0700, Paul Zimmerman wrote:
> > -----Original Message-----
> > From: Felipe Balbi [mailto:balbi@xxxxxx]
> > Sent: Thursday, August 25, 2011 1:36 PM
> > To: Sarah Sharp
> > Cc: Felipe Balbi; Greg KH; Linux USB Mailing List; Linux OMAP Mailing List; Paul Zimmerman
> > Subject: Re: [PATCH 3/4] usb: Introduce DesignWare USB3 DRD Driver
> > 
> > Hi,
> > 
> > On Thu, Aug 25, 2011 at 12:15:09PM -0700, Sarah Sharp wrote:
> > > On Fri, Aug 19, 2011 at 06:10:58PM +0300, Felipe Balbi wrote:
> > > > +enum dwc3_link_state {
> > > > +	/* In SuperSpeed */
> > > > +	DWC3_LINK_STATE_U0		= 0x00, /* in HS, means ON */
> > > > +	DWC3_LINK_STATE_U1		= 0x01,
> > > > +	DWC3_LINK_STATE_U2		= 0x02, /* in HS, means SLEEP */
> > > > +	DWC3_LINK_STATE_U3		= 0x03, /* in HS, means SUSPEND */
> > > > +	DWC3_LINK_STATE_SS_DIS		= 0x04,
> > > > +	DWC3_LINK_STATE_RX_DET		= 0x05, /* in HS, means Early Suspend */
> > > > +	DWC3_LINK_STATE_SS_INACT	= 0x06,
> > > > +	DWC3_LINK_STATE_POLL		= 0x07,
> > > > +	DWC3_LINK_STATE_RECOV		= 0x08,
> > > > +	DWC3_LINK_STATE_HRESET		= 0x09,
> > > > +	DWC3_LINK_STATE_CMPLY		= 0x0a,
> > > > +	DWC3_LINK_STATE_LPBK		= 0x0b,
> > > > +	DWC3_LINK_STATE_MASK		= 0x0f,
> > > > +};
> > >
> > > AFAICT, the link state values are exactly the same as the xHCI link
> > > state values in the Port Link State field in the PORTSC register.  Is
> > > the gadget side (xDCI side) meant to be somewhat compatible with the
> > > xHCI host controller spec?
> > 
> > I guess Synopsys would be best to answer this question. Paul, do you
> > happen to know the answer ?
> > 
> > > Would it make sense to share these link state macros (and any other
> > > similar #defines) with the xHCI driver?  We could move them into
> > > include/linux/ch11.h.
> > 
> > I'm not sure it makes sense to make gadget side use ch11 definitions,
> > but we could move them to some other common header, maybe ?
> 
> Our USB3 core is a dual-role device, and some of the logic is shared
> between xHCI mode and Device mode. So it's not a coincidence that the
> link state values are the same.
> 
> However, in future the device mode will have additional states beyond
> those defined for xHCI. So a completely common header file is not
> possible, unless people don't mind having Synopsys-specific defines
> inside it.

Thanks for the reply Paul :-) I believe this is strong enough argument
to keep things as they are.

-- 
balbi

Attachment: signature.asc
Description: Digital signature


[Index of Archives]     [Linux Arm (vger)]     [ARM Kernel]     [ARM MSM]     [Linux Tegra]     [Linux WPAN Networking]     [Linux Wireless Networking]     [Maemo Users]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Trails]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux