Re: request_irq() return value

From: Stephen Hemminger
Date: Thu Jul 27 2006 - 14:11:56 EST

On Thu, 27 Jul 2006 19:50:03 +0200
Mariusz Kozlowski <m.kozlowski@xxxxxxxxxx> wrote:

> Hello,
> I'm looking at the source code of different drivers and wondering about
> request_irq() return value. It is used mostly in 'open' routine of struct
> net_device. If request_irq() fails some drivers return -EAGAIN, some -EBUSY
> and some the return value of request_irq(). Is this intentional? Sample
> drivers code:

Correct practice is to propagate the error code of request_irq out to be
the return value of the open routine. This allows the request_irq to return
different values for overlapping irqs, or out of memory, etc.

> Besides request_irq() is arch dependent so depending on arch it has different
> set of possible return values. So ... does the return value matter or I
> misunderstood something here?

Each architecture should return something sane. If it doesn't then it a problem
that should be addressed there.
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