On Fri, Jun 5, 2020 at 12:14 AM Michael Walle [off-list ref] wrote:

Add support for the GPIO controller of the sl28 board management
controller. This driver is part of a multi-function device.

A controller has 8 lines. There are three different flavors:
full-featured GPIO with interrupt support, input-only and output-only.

...

+#include <linux/of_device.h>

I think also not needed.
But wait...

+       return devm_regmap_add_irq_chip_np(dev, dev_of_node(dev), regmap,

It seems regmap needs to be converted to use fwnode.

+                                          irq, IRQF_SHARED | IRQF_ONESHOT, 0,
+                                          irq_chip, &gpio->irq_data);

...

+       if (!pdev->dev.parent)
+               return -ENODEV;

Are we expecting to get shot into foot? I mean why we need this check?

+       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.

+       else
+               type = (uintptr_t)of_device_get_match_data(&pdev->dev);

So does this. device_get_match_data().

+       if (!type)
+               return -ENODEV;

...

+       if (irq_support &&

Why do you need this flag? Can't simple IRQ number be sufficient?

+           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);
+       }

...

+static const struct of_device_id sl28cpld_gpio_of_match[] = {

+       { .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.

+       {},

No comma.

+};

...

+               .name = KBUILD_MODNAME,

This actually not good idea in long term. File name can change and break an ABI.

-- 
With Best Regards,
Andy Shevchenko