lkml.org 
[lkml]   [2013]   [Jan]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/2] ARM: sunxi: gpio: Add Allwinner SoCs GPIO drivers
Hi Linus,

On 10/01/2013 12:06, Linus Walleij wrote:
> On Fri, Jan 4, 2013 at 5:45 PM, Maxime Ripard
> <maxime.ripard@free-electrons.com> wrote:
>> +static int __devinit
>> +sunxi_pinctrl_register_gpio_ranges(struct sunxi_pinctrl *pctl)
>> +{
>> + int id = 0, base = 0, npins = 1, i, prev_pin = -1;
>> + struct pinctrl_gpio_range *range;
>> +
>> + for (i = 0; i < pctl->desc->npins; i++) {
>> + const struct sunxi_desc_pin *pin = pctl->desc->pins + i;
>> + unsigned pin_num = pin->pin.number;
>> +
>> + if (prev_pin < 0) {
>> + prev_pin = pin_num;
>> + base = pin_num;
>> + } else if (prev_pin + 1 != pin_num) {
>> + range = devm_kzalloc(pctl->dev,
>> + sizeof(*range),
>> + GFP_KERNEL);
>> + if (!range)
>> + return -ENOMEM;
>> +
>> + range->name = "sunxi";
>> + range->id = id;
>> + range->base = base;
>> + range->pin_base = base;
>> + range->npins = npins;
>> +
>> + pinctrl_add_gpio_range(pctl->pctl_dev, range);
>> +
>> + id++;
>> + npins = 1;
>> + prev_pin = pin_num;
>> + base = prev_pin;
>> + } else {
>> + prev_pin++;
>> + npins++;
>> + }
>> + }
>> +
>> + range = devm_kzalloc(pctl->dev, sizeof(*range),
>> + GFP_KERNEL);
>> + if (!range)
>> + return -ENOMEM;
>> +
>> + range->name = "sunxi";
>> + range->id = id;
>> + range->base = base;
>> + range->pin_base = base;
>> + range->npins = npins;
>> +
>> + pinctrl_add_gpio_range(pctl->pctl_dev, range);
>> +
>> + return 0;
>> +}
>
> Really hairy way to add ranges right?

Yes... I didn't find any best way to do so. It was either that or
duplicate the already existing informations we had about the pins ranges
into a ranges array, which is pretty error-prone.

I guess I could add some comments though.

> Registering ranges from the pinctrl side is deprecated and discouraged.
>
> Instead register the ranges from the GPIO driver.
>
> Use gpiochip_add_pin_range() from the GPIO driver.
>
> An example is provided in
> drivers/pinctrl/pinctrl-coh901.c

Ok, will do. But we need to find a way to share the pins arrays between
the pinctrl and gpio drivers then.

Maybe add a pinctrl-sunxi-pins.h file? or merge the pinctrl and gpio
drivers?

I'm kind of reluctant to merging the drivers into one single messy file,
but if that's the way to go, fine.

>
> After you have done this, you can probably get rid of this as well:
>
> +static int __init sunxi_gpio_init(void)
> +{
> + return platform_driver_register(&sunxi_gpio_driver);
> +}
> +postcore_initcall(sunxi_gpio_init);
>
> This will become a simple module_init() if you are handling
> deferred probe correctly.

Ok. Thanks for your review!
Maxime

--
Maxime Ripard, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com


\
 
 \ /
  Last update: 2013-01-12 10:41    [W:0.064 / U:12.684 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site