Subject: [PATCH 1/2] pinctrl: Add Oxford Semiconductor OXNAS pinctrl and gpio driver

From: [email-masked] (Neil Armstrong)
Date: Mon, 18 Apr 2016 10:26:06 +0200

On 04/13/2016 03:42 PM, Linus Walleij wrote:
> On Sun, Apr 3, 2016 at 3:26 PM, Neil Armstrong <[email-masked]> wrote:
> 
>> Add pinctrl and gpio control support to Oxford Semiconductor OXNAS SoC Family.
>> This version supports the ARM926EJ-S based OX810SE SoC with 34 IO pins.
>>
>> Signed-off-by: Neil Armstrong <[email-masked]>
> 
> Starting to look very nice :)
> 
>> +static inline struct oxnas_gpio_bank *irqd_to_bank(struct irq_data *d)
>> +{
>> +       return gpiochip_get_data(irq_data_get_irq_chip_data(d));
>> +}
> 
> Do you really need to wrap this call? Seems like pointless layer of
> abstraction to me.

Sure, I'll remove it.

>> +       if (of_parse_phandle_with_fixed_args(np, "gpio-ranges",
>> +                                            3, 0, &pinspec)) {
>> +               dev_err(&pdev->dev, "gpio-ranges property not found\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       id = pinspec.args[1] / PINS_PER_BANK;
>> +       ngpios = pinspec.args[2];
>> +
>> +       if (id >= ARRAY_SIZE(oxnas_gpio_banks)) {
>> +               dev_err(&pdev->dev, "invalid gpio-ranges base arg\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       if (ngpios > PINS_PER_BANK) {
>> +               dev_err(&pdev->dev, "invalid gpio-ranges count arg\n");
>> +               return -EINVAL;
>> +       }
>> +
>> +       bank = &oxnas_gpio_banks[id];
> 
> This feels a bit hackish but I guess that is how we have to do things
> then :/

It seems I'll need to stick with this for the moment :/

>> +static int __init oxnas_gpio_register(void)
>> +{
>> +       return platform_driver_register(&oxnas_gpio_driver);
>> +}
>> +arch_initcall(oxnas_gpio_register);
>> +
>> +static int __init oxnas_pinctrl_register(void)
>> +{
>> +       return platform_driver_register(&oxnas_pinctrl_driver);
>> +}
>> +arch_initcall(oxnas_pinctrl_register);
> 
> Why do these have to be arch_initcall()?
> 
> I'm not very happy with anything below subsys_initcall()
> and others prefer that you have only device_initcall().
> 
> I need some rationale. Sorry if I already asked...

Actually, arch_initcall seems the best level to permit further device to get interrupts from these gpio controllers, AFAIK quite all the upstream pinctrl driver uses arch_ or subsys_.

> Yours,
> Linus Walleij

Thanks,
Neil