svn commit: r217718 - in head/sys: conf dev/usb

[Hans Petter Selasky]

On Saturday 22 January 2011 16:09:18 Gary Jennejohn wrote:
> On Sat, 22 Jan 2011 13:52:23 +0000 (UTC)
> 
> Hans Petter Selasky <hselasky at FreeBSD.org> wrote:
> > Author: hselasky
> > Date: Sat Jan 22 13:52:23 2011
> > New Revision: 217718
> > URL: http://svn.freebsd.org/changeset/base/217718
> > 
> > Log:
> >   Allow USB_HOST_ALIGN to be configured at compile time. This patch is
> >   necessary for MIPS based RouterStation Pro board and maybe other MIPS
> >   based boards as well.
> >   
> >   Submitted by:	Milan Obuch
> >   Approved by:	thompsa (mentor)
> > 
> > Modified:
> >   head/sys/conf/options
> >   head/sys/dev/usb/usb_freebsd.h
> > 
> > Modified: head/sys/conf/options
> > =========================================================================
> > ===== --- head/sys/conf/options	Sat Jan 22 13:18:28 2011	(r217717)
> > +++ head/sys/conf/options	Sat Jan 22 13:52:23 2011	(r217718)
> > @@ -642,6 +642,7 @@ BUS_DEBUG		opt_bus.h
> > 
> >  # options for USB support
> >  USB_DEBUG		opt_usb.h
> > 
> > +USB_HOST_ALIGN		opt_usb.h

Sorry I didn't see this option sneaking in during r217631 :-) Anyway, two 
times is better than one time :-)

> > 
> >  USB_REQ_DEBUG		opt_usb.h
> >  USB_VERBOSE		opt_usb.h
> >  USB_EHCI_BIG_ENDIAN_DESC	opt_usb.h
> > 
> > Modified: head/sys/dev/usb/usb_freebsd.h
> > =========================================================================
> > ===== --- head/sys/dev/usb/usb_freebsd.h	Sat Jan 22 13:18:28
> > 2011	(r217717) +++ head/sys/dev/usb/usb_freebsd.h	Sat Jan 22 13:52:23
> > 2011	(r217718) @@ -46,7 +46,12 @@
> > 
> >  #define	USB_TD_GET_PROC(td) (td)->td_proc
> >  #define	USB_PROC_GET_GID(td) (td)->p_pgid
> > 
> > +#if defined(USB_HOST_ALIGN) && (USB_HOST_ALIGN != 0)
> > +/* USB_HOST_ALIGN is already defined and valid */
> 
> Not necessarily valid. What if the user sets it to -24?  The compiler
> will happily accept that with the above #if-statement.
> 
> IMO you should test for USB_HOST_ALIGN > 0, which should always work.
> 
> Defensive programming is always a good idea.

I agree.

Does this look OK:

#if defined(USB_HOST_ALIGN) && (USB_HOST_ALIGN != 0)
#if (-USB_HOST_ALIGN & USB_HOST_ALIGN) == USB_HOST_ALIGN
#error "USB_HOST_ALIGN is not power of two."
#endif
#if (USB_HOST_ALIGN <= 0)
#error "USB_HOST_ALIGN is less than or equal to zero."
#endif

...

> 
> > +#else
> > +#undef USB_HOST_ALIGN
> > 
> >  #define	USB_HOST_ALIGN    8		/* bytes, must be power of two */
> > 
> > +#endif
> > 
> >  #define	USB_FS_ISOC_UFRAME_MAX 4	/* exclusive unit */
> >  #define	USB_BUS_MAX 256			/* units */
> >  #define	USB_MAX_DEVICES 128		/* units */

--HPS