On Fri, Jun 05, 2020 at 02:42:53PM +0200, Michael Walle wrote:
> Am 2020-06-05 14:00, schrieb Andy Shevchenko:
> > On Fri, Jun 5, 2020 at 12:14 AM Michael Walle <michael@xxxxxxxx> wrote:
> > > + return devm_regmap_add_irq_chip_np(dev, dev_of_node(dev),
> > > regmap,
> >
> > It seems regmap needs to be converted to use fwnode.
>
> Mhh, this _np functions was actually part of this series in the
> beginning.
Then, please, make them fwnode aware rather than OF centric.
> > > IRQF_ONESHOT, 0,
> > > + irq_chip, &gpio->irq_data);
...
> > > + dev_id = platform_get_device_id(pdev);
> > > + if (dev_id)
> > > + type = dev_id->driver_data;
> >
> > Oh, no. In new code we don't need this. We have facilities to provide
> > platform data in a form of fwnode.
>
> Ok I'll look into that.
>
> But I already have a question, so there are of_property_read_xx(), which
> seems to be the old functions, then there is device_property_read_xx() and
> fwnode_property_read_xx(). What is the difference between the latter two?
It's easy. device_*() requires struct device to be established for this, so,
operates only against devices, while the fwnode_*() operates on pure data which
might or might not be related to any devices. If you understand OF examples
better, consider device node vs. child of such node.
...
> > > + if (irq_support &&
> >
> > Why do you need this flag? Can't simple IRQ number be sufficient?
>
> I want to make sure, the is no misconfiguration. Eg. only GPIO
> flavors which has irq_support set, have the additional interrupt
> registers.
In gpio-dwapb, for example, we simple check two things: a) hardware limitation
(if IRQ is assigned to a proper port) and b) if there is any IRQ comes from DT,
ACPI, etc.
> > > + device_property_read_bool(&pdev->dev,
> > > "interrupt-controller")) {
> > > + irq = platform_get_irq(pdev, 0);
> > > + if (irq < 0)
> > > + return irq;
> > > +
> > > + ret = sl28cpld_gpio_irq_init(&pdev->dev, gpio, regmap,
> > > + base, irq);
> > > + if (ret)
> > > + return ret;
> > > +
> > > + config.irq_domain =
> > > regmap_irq_get_domain(gpio->irq_data);
> > > + }
...
> > > + { .compatible = "kontron,sl28cpld-gpio",
> > > + .data = (void *)SL28CPLD_GPIO },
> > > + { .compatible = "kontron,sl28cpld-gpi",
> > > + .data = (void *)SL28CPLD_GPI },
> > > + { .compatible = "kontron,sl28cpld-gpo",
> > > + .data = (void *)SL28CPLD_GPO },
> >
> > All above can be twice less LOCs.
>
> They are longer than 80 chars. Or do I miss something?
We have 100 :-)
...
> > > + .name = KBUILD_MODNAME,
> >
> > This actually not good idea in long term. File name can change and break
> > an ABI.
>
> Ahh an explanation, why this is bad. Ok makes sense, although to be fair,
> .id_table should be used for the driver name matching. I'm not sure if
> this is used somewhere else, though.
I saw in my practice chain of renames for a driver. Now, if somebody
somewhere would like to instantiate a platform driver by its name...
Oops, ABI breakage.
And of course using platform data for such device makes less sense.
--
With Best Regards,
Andy Shevchenko
