Re: [RFC PATCH 1/2] serial: 8250: Add a notifier chain for driverregistration.

From: Grant Likely
Date: Thu Mar 17 2011 - 14:25:22 EST

On Thu, Mar 17, 2011 at 12:18:49PM +0000, Alan Cox wrote:
> On Wed, 16 Mar 2011 18:26:06 -0700
> David Daney <ddaney@xxxxxxxxxxxxxxxxxx> wrote:
> > The 8250 driver is a bit weird in that in addition to supporting
> > platform devices, extra devices can be added by calling
> > serial8250_register_port().
> >
> > The problem is that if we call serial8250_register_port() before the
> > driver is initialized Bad Things happen (we dereference NULL
> > pointers).
> >
> > There doesn't seem to be a general way to know if a driver has been
> > initialized
> I've had a bigger dig into this. I think the correct answer is probably
> "always go via platform devices or similar". That *is* the notifier in
> the kernel of today. serial8250_register_port ultimately should I think
> ultimatly become an internal helper.


Depending on serial8250_register_port() definitely the wrong thing to
do for platform support code. It would be better to figure out how to
get the dt bits you need into 8250.c or of_serial.c.


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