On Tue, Dec 30, 2014 at 10:33:26AM -0500, Ahmed S. Darwish wrote:
> On Sun, Dec 28, 2014 at 10:51:34PM +0100, Olivier Sobrie wrote:
> [...]
> > > > >  
> > > > > +     if (LEAF_PRODUCT_ID(id->idProduct)) {
> > > > > +             dev->family = KVASER_LEAF;
> > > > > +             dev->max_channels = LEAF_MAX_NET_DEVICES;
> > > > > +     } else if (USBCAN_PRODUCT_ID(id->idProduct)) {
> > > > > +             dev->family = KVASER_USBCAN;
> > > > > +             dev->max_channels = USBCAN_MAX_NET_DEVICES;
> > > > > +     } else {
> > > > > +             dev_err(&intf->dev, "Product ID (%d) does not belong to 
> > > > > any "
> > > > > +                                 "known Kvaser USB family", 
> > > > > id->idProduct);
> > > > > +             return -ENODEV;
> > > > > +     }
> > > > > +
> > > > 
> > > > Is it really required to keep max_channels in the kvaser_usb structure?
> > > > If I looked correctly, you use this variable as a replacement for
> > > > MAX_NET_DEVICES in the code and MAX_NET_DEVICES is only used in probe
> > > > and disconnect functions. I think it can even be replaced by nchannels
> > > > in the disconnect path. So I also think that it don't need to be in the
> > > > kvaser_usb structure.
> > > > 
> > > 
> > > hmmm.. given the current state of error arbitration explained
> > > above, where I cannot accept a dev->nchannels > 2, I guess we
> > > have two options:
> > > 
> > > a) Remove max_channels, and hardcode the channels count
> > > correctness logic as follows:
> > > 
> > >         dev->nchannels = msg.u.cardinfo.nchannels;
> > >         if ((dev->family == USBCAN && dev->nchannels > 
> > > USBCAN_MAX_NET_DEVICES)
> > >             || (dev->family == LEAF && dev->nchannels > 
> > > LEAF_MAX_NET_DEVICES))
> > >                 return -EINVAL
> > > 
> > > b) Leave max_channels in 'struct kvaser_usb' as is.
> > > 
> > > I personally prefer the solution at 'b)' but I can do it as
> > > in 'a)' if you prefer :-)
> > 
> > Keeping max_channels in the kvaser_usb structure is useless because it
> > is only used in one function that is called in the probe function.
> > 
> > I would prefer to have:
> >     if (dev->nchannels > MAX_NET_DEVICES)
> >             return -EINVAL
> > 
> >     if ((dev->family == USBCAN) &&
> >         (dev->nchannels > MAX_USBCAN_NET_DEVICES))
> >             return -EINVAL
> > 
> > You can remove LEAF_MAX_NET_DEVICES which is not used, keep
> > MAX_NET_DEVICES equals to 3 and remove the MAX() macro.
> > The test specific to the USBCAN family can eventually be moved in the
> > kvaser_usb_probe() function.
> > 
> 
> Quite nice, will do it that way in v3.
> 

Thank you.
Please also check your patches with scripts/checkpatch.pl.
I see several warnings when I run it. Please fix them.

All the best for New Year's Eve,

-- 
Olivier
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to