lkml.org 
[lkml]   [2014]   [Apr]   [15]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
SubjectRe: [PATCH V7 1/1] drivers/gpio: Altera soft IP GPIO driver and devicetree binding
From
>>>>> Add driver support for Altera GPIO soft IP, including interrupts and I/O.
>>>>> Tested on Altera CV SoC board using dipsw and LED using LED framework.
>>>>>
>>>>> Signed-off-by: Tien Hock Loh <thloh@altera.com>
>>>>> ---
>>>>
>>>>> + return -ENOMEM;
>>>>> + }
>>>>> + altera_gc->domain = 0;
>>>>> +
>>>>> + spin_lock_init(&altera_gc->gpio_lock);
>>>>> +
>>>>> + id = pdev->id;
>>>>> +
>>>>> + if (of_property_read_u32(node, "altr,gpio-bank-width", &reg))
>>>>> + /*By default assume full GPIO controller*/
>>>>> + altera_gc->mmchip.gc.ngpio = 32;
>>>>> + else
>>>>> + altera_gc->mmchip.gc.ngpio = reg;
>>>>> +
>>>>> + if (altera_gc->mmchip.gc.ngpio > 32) {
>>>>> + dev_warn(&pdev->dev,
>>>>> + "ngpio is greater than 32, defaulting to 32\n");
>>>>> + altera_gc->mmchip.gc.ngpio = 32;
>>>>> + }
>>>>> +
>>>>> + altera_gc->mmchip.gc.direction_input = altera_gpio_direction_input;
>>>>> + altera_gc->mmchip.gc.direction_output = altera_gpio_direction_output;
>>>>> + altera_gc->mmchip.gc.get = altera_gpio_get;
>>>>> + altera_gc->mmchip.gc.set = altera_gpio_set;
>>>>> + altera_gc->mmchip.gc.to_irq = altera_gpio_to_irq;
>>>>> + altera_gc->mmchip.gc.owner = THIS_MODULE;
>>>>> +
>>>>> + ret = of_mm_gpiochip_add(node, &altera_gc->mmchip);
>>>>> + if (ret) {
>>>>> + dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n");
>>>>> + return ret;
>>>>> + }
>>>>> +
>>>>> + platform_set_drvdata(pdev, altera_gc);
>>>>> +
>>>>> + altera_gc->mapped_irq = irq_of_parse_and_map(node, 0);
>>>>>
>>>>
>>>> platform_get_irq(pdev, 0);
>>>>
>>> OK.
>>>
>>
>> platform_get_irq doesn't create the irq mapping which is needed by the
>> driver. Since this driver is targeted at using of, should I be using
>> irq_of_parse_and_map or should I still redo the codes with
>> platform_get_irq and irq_create_mapping? I think the latter would be
>> introducing code redundancy. Please advice.
>
> Yes, it is technically true that platform_get_irq() doesn't do the mapping directly, but that's
> because the mapping is setup earlier, when
> of_device_alloc() (drivers/of/platform.c) allocates resources for your platform device.
>
> Calling irq_of_parse_and_map() should be unnecessary.

I checked and tried running the without irq_create_mapping but it
seems the mapping is not done.
What I've seen other GPIO driver is doing is to create the mapping
during the gpio_to_irq call. However Linus suggested we are avoiding
that route, thus the use of irq_of_parse_and_map. Do you agree with my
findings?

>>
>> Thanks.


\
 
 \ /
  Last update: 2014-04-15 12:21    [W:0.072 / U:1.972 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site