On Wed, Apr 01, 2020 at 10:55:48AM +0200, Greg Kroah-Hartman wrote:
> On Wed, Apr 01, 2020 at 05:27:20PM +0900, Hyunki Koo wrote:
> > - if (np)
> > + if (np) {
> > of_property_read_u32(np,
> > "samsung,uart-fifosize", &ourport->port.fifosize);
> >
> > + if (of_property_read_u32(np, "reg-io-width", &prop) == 0) {
> > + switch (prop) {
> > + case 1:
> > + ourport->port.iotype = UPIO_MEM;
> > + break;
> > + case 4:
> > + ourport->port.iotype = UPIO_MEM32;
> > + break;
> > + default:
> > + dev_warn(&pdev->dev, "unsupported reg-io-width (%d)\n",
> > + prop);
> > + ret = -EINVAL;
> > + break;
> > + }
> > + }
> > + }
> > +
>
> Does this mean that reg-io-width is now a required property for all
> samsung uarts? Does this break older dts files? Or should you
> fall-back to the previous operation if the attribute is not there?
Yes, it looks like silently breaking all boards. Since
of_property_read_u32() will return errno, the warning message won't be
printed and all register reads will fail (return 0).
This looks like not tested on real HW.
Best regards,
Krzysztof
