On Wednesday 22 January 2014 11:14:09 Jason Gunthorpe wrote: > On Wed, Jan 22, 2014 at 03:01:01PM -0300, Ezequiel Garcia wrote: > > On Wed, Jan 22, 2014 at 01:21:36PM -0300, Ezequiel Garcia wrote: > > > > I don't see a good way out that would preserve backwards compatibility, > > > > other than hardcoding the physical address in the driver, which seems > > > > just as bad as breaking compatibility. That said, it is always the > > > > same constant (0xf1000000 + 0x20000 + 0x0108) on Dove, Kirkwood and > > > > Orion5x (not on mv78xx0, but that doesn't use the wdt), so hardcoding > > > > a fallback would technically work, but we should print a fat warning at > > > > boot time if we actually fall back to that. > > > > > > > > > > Yes, I was thinking just about this. Namely: > > > > > [..] > > > > How about something like this? > > I liked Arnd's idea to use an offset from the first register. With the > mbus driver we can now actually change the 0xF1.. prefix via the DT. That wasn't actually my idea, but it does sound reasonable. > > + dev_warn(&pdev->dev, "falling back to harcoded RSTOUT reg 0x%x\n", > > + ORION_RSTOUT_MASK); > > Maybe: > dev_warn(&pdev->dev, FW_BUG "falling back to harcoded RSTOUT reg 0x%x\n", I was thinking of WARN_ON(), i.e. something that users will actually notice ;-) > > @@ -139,10 +166,7 @@ static int orion_wdt_probe(struct platform_device *pdev) > > if (!wdt_reg) > > return -ENOMEM; > > > > - res = platform_get_resource(pdev, IORESOURCE_MEM, 1); > > - if (!res) > > - return -ENODEV; > > - wdt_rstout = devm_ioremap(&pdev->dev, res->start, resource_size(res)); > > + wdt_rstout = try_compat_rstout_ioremap(pdev); > > if (!wdt_rstout) > > return -ENOMEM; > > ENOMEM is probably not the right errno? Is there a standard errno for > malformed DT? I don't think so. I'd probably use ENODEV, but it's not ideal. Arnd -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
