Re: [PATCH 11/16] powerpc: vio_cmo: use dev_groups and not dev_attrs for bus_type

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Fri, Jun 09, 2017 at 08:53:22AM +1000, Michael Ellerman wrote:
> Greg Kroah-Hartman <gregkh@linuxfoundation.org> writes:
> 
> > On Thu, Jun 08, 2017 at 11:12:10PM +1000, Michael Ellerman wrote:
> >> Greg Kroah-Hartman <gregkh@linuxfoundation.org> writes:
> >> 
> >> > The dev_attrs field has long been "depreciated" and is finally being
> >> > removed, so move the driver to use the "correct" dev_groups field
> >> > instead for struct bus_type.
> >> >
> >> > Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> >> > Cc: Paul Mackerras <paulus@samba.org>
> >> > Cc: Michael Ellerman <mpe@ellerman.id.au>
> >> > Cc: Vineet Gupta <vgupta@synopsys.com>
> >> > Cc: Bart Van Assche <bart.vanassche@sandisk.com>
> >> > Cc: Robin Murphy <robin.murphy@arm.com>
> >> > Cc: Joerg Roedel <jroedel@suse.de>
> >> > Cc: Johan Hovold <johan@kernel.org>
> >> > Cc: Alexey Kardashevskiy <aik@ozlabs.ru>
> >> > Cc: Krzysztof Kozlowski <krzk@kernel.org>
> >> > Cc: <linuxppc-dev@lists.ozlabs.org>
> >> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> >> > ---
> >> >  arch/powerpc/platforms/pseries/vio.c | 37 +++++++++++++++++++++---------------
> >> >  1 file changed, 22 insertions(+), 15 deletions(-)
> >> 
> >> This one needed a bit more work to get building, the incremental diff is
> >> below. We need a forward declaration of name, devspec and modalias,
> >> which is a bit weird, but that's how the code is currently structured.
> >> And there's dev and bus attributes with the same name, so that needed an
> >> added "bus".
> >> 
> >> I booted v2 of patch 10 and this one and everything looks identical to
> >> upstream.
> >
> > Ah, many thanks, this was on my todo list to fix up today.
> >
> > But you renamed the sysfs files when you added "bus" to the function
> > names, are you sure you want to do that?  I don't mind, but if you
> > happen to have userspace tools that look at those files, they just broke
> > :(
> 
> Ugh crap, no that won't work.
> 
> I didn't see it when I tested because my machine doesn't have the CMO
> feature enabled.
> 
> I guess we have to open code some of the BUS_ATTR_RO() etc. so we can
> avoid the name clash.

Or split it into multiple files, I've solved this that way in the past.
You shouldn't have to "open code" BUS_ATTR_RO().

thanks,

greg k-h