[RFC 2/9] WIP: fix drivers/usb/core/usb.c

[Sascha Hauer]

On Fri, Aug 28, 2015 at 06:51:04PM +0300, Antony Pavlov wrote:
> On Fri, 28 Aug 2015 08:11:59 +0200
> Sascha Hauer <s.hauer at pengutronix.de> wrote:
> 
> > On Fri, Aug 28, 2015 at 01:24:03AM +0300, Antony Pavlov wrote:
> > > drivers/usb/core/usb.c: In function 'usb_parse_config':
> > > drivers/usb/core/usb.c:194:28: error: 'struct usb_configuration' has no
> > > member named 'wTotalLength'
> > >   le16_to_cpus(&(dev->config.wTotalLength));
> > >                             ^
> > > ...
> > > scripts/Makefile.build:249: recipe for target 'drivers/usb/core/usb.o'
> > > failed
> > > make[3]: *** [drivers/usb/core/usb.o] Error 1
> > > scripts/Makefile.build:387: recipe for target 'drivers/usb/core' failed
> > > make[2]: *** [drivers/usb/core] Error 2
> > > scripts/Makefile.build:387: recipe for target 'drivers/usb' failed
> > > make[1]: *** [drivers/usb] Error 2
> > > Makefile:770: recipe for target 'drivers' failed
> > > make: *** [drivers] Error 2
> > > 
> > > see also
> > > 
> > > commit 245069bcef15ecc19db616a967501349b76c84d0
> > > Author: Sascha Hauer <s.hauer at pengutronix.de>
> > > Date:   Thu Jul 10 11:36:12 2014 +0200
> > > 
> > >     USB: introduce usb_interface/usb_configuration structs
> > > 
> > >     Currently we have two conflicting definitions of struct
> > > usb_config_descriptor
> > >     and struct usb_interface_descriptor in the tree. This is because the
> > > USB code
> > >     uses additional fields in the structs for internal housekeeping. Add
> > >     struct usb_interface and struct struct usb_configuration with the
> > > housekeeping
> > >     data and embed the corresponding hardware structs into them. This
> > > frees the
> > >     way to use the definitions from ch9.h in the next step.
> > > 
> > > Signed-off-by: Antony Pavlov <antonynpavlov at gmail.com>
> > > ---
> > >  drivers/usb/core/usb.c | 2 +-
> > >  1 file changed, 1 insertion(+), 1 deletion(-)
> > > 
> > > diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
> > > index 9073fff..f8d6014 100644
> > > --- a/drivers/usb/core/usb.c
> > > +++ b/drivers/usb/core/usb.c
> > > @@ -191,7 +191,7 @@ static int usb_parse_config(struct usb_device *dev, unsigned char *buffer, int c
> > >  		return -1;
> > >  	}
> > >  	memcpy(&dev->config, buffer, buffer[0]);
> > > -	le16_to_cpus(&(dev->config.wTotalLength));
> > > +	le16_to_cpus(&(dev->config.desc.wTotalLength));
> > >  	dev->config.no_of_if = 0;
> > 
> > 
> > What's WIP in this patch? It looks 100% correct.
> 
> WIP means that I don't understand why nobody but me detected this build problem.
> Have you any idea?

Yeah, I wondered about this aswell at first, but it's quite easy if you
look at it. le16_to_cpus converts the content of a pointer to le16 to
cpu endianess.  On little endian systems like ARM this is a no op,
defined as:

#define le16_to_cpus __le16_to_cpus
#define __le16_to_cpus(x) do {} while (0)

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |