Re: [PATCH] of: Export of_irq_count for using in modules

From: Michal Simek
Date: Fri May 31 2013 - 12:45:36 EST


On 05/31/2013 05:16 PM, Jean-Christophe PLAGNIOL-VILLARD wrote:
> On 15:57 Fri 31 May , Michal Simek wrote:
>> On 05/31/2013 01:00 PM, Jean-Christophe PLAGNIOL-VILLARD wrote:
>>> On 10:14 Fri 31 May , Michal Simek wrote:
>>>> Hi Jean-Christophe,
>>>>
>>>> On 05/30/2013 10:17 PM, Jean-Christophe PLAGNIOL-VILLARD wrote:
>>>>> On 15:49 Thu 30 May , Michal Simek wrote:
>>>>>> Export of_irq_count for modules.
>>>>>
>>>>> can you explain why do you need to call of_irq_count
>>>>
>>>> I need to count number of irq written in the DTS node.
>>>> It is not fixed size that's why I need to proper way how to
>>>> find it out.
>>>>
>>>> I am using this loop.
>>>> count = of_irq_count(pdev->dev.of_node);
>>>> /* Alloc IRQ based on DTS to be sure that no other driver will use it */
>>>> while (count--) {
>>>> tmp->irq = irq_of_parse_and_map(pdev->dev.of_node, count);
>>>> dev_info(&pdev->dev, "%d: Alloc irq: %d\n", count, tmp->irq);
>>>> ret = request_irq(tmp->irq, zynq_remoteproc_interrupt, 0,
>>>> dev_name(&pdev->dev), &pdev->dev);
>>>> if (ret) {
>>>> ...
>>>> }
>>>> }
>>>>
>>>> But of course if you think that this is incorrect to export it
>>>> I can use what it is in of_irq_count body
>>>> 368 int of_irq_count(struct device_node *dev)
>>>> 369 {
>>>> 370 int nr = 0;
>>>> 371
>>>> 372 while (of_irq_to_resource(dev, nr, NULL))
>>>> 373 nr++;
>>>> 374
>>>> 375 return nr;
>>>> 376 }
>>>>
>>>> Because of_irq_to_resource is exported for modules.
>>>> Or is there any better way how to loop over all interrupts in DT node?
>>>
>>> can just explain me why you need to call irq_of_parse_and_map in your driver?
>>>
>>> as the irq will be provided in the resources normally
>>
>> It is quite a long time I have written this driver on v3.1 or 3.3.
>> But is this better?
>>
>> struct resource *res;
>> int i = 0;
>> do {
>> res = platform_get_resource(pdev, IORESOURCE_IRQ, i++);
>> if (res)
>> do something
>> } while(res);
>>
>> Also what about of_irq_to_resource()? Is it deprecated and all drivers
>> shouldn't use it?
>>
>> I have no problem to rewrite the driver to use platform_get_resource.
> yeah it's better but be aware there is a but in DT that I'm working on to fix
> if you use irq that are registered by a pdev this will not work
>
> I hope to fix it for 3.11
> and already send an RFC that fix it

ok. good to know. Btw: Let's return to my origin point why not to
export of_irq_count for modules?
Or opposite question if platform_get_resource is correct way
why to export of_irq_to_resource for modules?

Thanks,
Michal

--
Michal Simek, Ing. (M.Eng), OpenPGP -> KeyID: FE3D1F91
w: www.monstr.eu p: +42-0-721842854
Maintainer of Linux kernel - Microblaze cpu - http://www.monstr.eu/fdt/
Maintainer of Linux kernel - Xilinx Zynq ARM architecture
Microblaze U-BOOT custodian and responsible for u-boot arm zynq platform


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