[PATCH 04/10] bus: introduce an Marvell EBU MBus driver

Ezequiel Garcia ezequiel.garcia at free-electrons.com
Thu Mar 7 20:02:28 EST 2013


Hi Jason,

On Thu, Mar 07, 2013 at 04:05:16PM -0700, Jason Gunthorpe wrote:
> On Thu, Mar 07, 2013 at 07:20:05PM -0300, Ezequiel Garcia wrote:
> > Now that the Device Bus driver is posted I think we have a nice example
> > on how address decoding windows would be allocated through the mbus
> > driver, *without* touching the child driver (i.e. NOR driver).
> 
> No, that isn't the case. Your device bus driver *is* the child driver,
> and you have touched it by adding mbus window code :)
> 
> In fact, looking at what you've done - with the DTs you've proposed
> your driver does *nothing* but make a call to the mbus driver to setup
> the windows for its children. Without timing parameters from the DT the
> driver does nothing else!
> 

Yes, setting aside the timings parameters, the Device Bus driver is only
charge of allocating the windows; perhaps we can say nothing more, nothing less :)

> > In conclusion: there is absolutely no need to change the NOR driver,
> > and there is no need to explictly add an explicit description of the
> > NOR window in the device tree.
> 
> As I've said, a DT that has child nodes without an associated address
> map is broken.
> 

Mmm... could explain me better, why you think it's *broken*?

Perhaps I'm slower than most people around here, but I still
don't fully understand this brokenness.

Thanks,
-- 
Ezequiel García, Free Electrons
Embedded Linux, Kernel and Android Engineering
http://free-electrons.com



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