Smitha,
Do you have the entry of this device node in your DTS file?
if yes, then is the device is getting registered properly?
If you are writing platform driver then you can use 'platform_get_irq'
it returns the irq number,
which you can pass in the 'request_irq'. If it is a simple character
driver then to determine the
virtual irq number you can use 'ioremap', in this call you can pass
the HW IRQ number e.g. 20
and then pass in the 'request_irq'.
But in both cases you have to have this device node in your device
tree and should be registered,
otherwise it should be returning error and no virtual irq will be allocated.
As per your return value it seems the device node is not getting
registered, perhaps the entry is
missing in DTS file. Try with just ioremap and see if virtual irq is
returned properly.
Kind Regards,
Vijay Nikam
On Mon, Oct 3, 2011 at 7:57 PM, <smitha.vanga at wipro.com> wrote:
>
> Hi Scott,
>
> I try to request an IRQ (IRQ2 and IRQ3 which are ineterrupt no 20 and 21 in
> mpc8247)in my driver . The
> Call fails in setup_irq in Manage.c at /kernel/irq.
>
> Setup _irq returns -ENOSYS
>
> if (desc->irq_data.chip == &no_irq_chip)
> return -ENOSYS;
>
>
> I found that I need to pass the virtual interrupt number instead of hardware
> interrupt number.
> So I added below piece of code
>
> Below is the call to request irq in my driver.
>
> virq = irq_create_mapping(NULL, CPLD1_INTERRUPT);
>
>
>
>
> if ((ret = request_irq(virq,cpld_irq_handler, 0, GPIO_CHAR_PATH,
> NULL))!=0)
> {
> printk(KERN_ERR "gpio_init: Could not grab IRQ line for CPLD ret =
> %d\n",ret);
> goto err1;
> }
>
>
> Now it fails in irq_create_mapping with NO_IRQ error.
>
> if (controller == NULL)
> host = irq_default_host;
> else
> host = irq_find_host(controller);
> if (host == NULL) {
> printk(KERN_WARNING "irq: no irq host found for %s !\n",
> controller->full_name);
> return NO_IRQ;
> }
>
>
> I just don't know what I should pass for host , also when I pass NULL for
> host . I see the default host is NULL..
> Could you please help me. My project delivery is near , I need help soon.
>
>
> Regards,
> Smitha
>
>
>
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