On Fri, Dec 10, 2021 at 4:47 AM Damien Le Moal
[off-list ref] wrote:

On 2021/12/09 23:59, Andy Shevchenko wrote:

quoted

platform_get_irq() will print a message when it fails.
No need to repeat this.

While at it, drop redundant check for 0 as platform_get_irq() spills
out a big WARN() in such case.

The reason you should be able to remove the "if (!irq)" test is that
platform_get_irq() never returns 0. At least, that is what the function kdoc
says. But looking at platform_get_irq_optional(), which is called by
platform_get_irq(), the out label is:

        WARN(ret == 0, "0 is an invalid IRQ number\n");
        return ret;

So 0 will be returned as-is. That is rather weird. That should be fixed to
return -ENXIO:

        if (WARN(ret == 0, "0 is an invalid IRQ number\n"))
                return -ENXIO;

No, this is wrong for the same reasons I explained to Sergey.
The problem is that this is _optional API and it has been misdesigned.
Replacing things like above will increase the mess.

        return ret;

Otherwise, I do not think that removing the "if (!irq)" hunk is safe. no ?

No. This is not a business of the caller to workaround implementation
details (bugs) of the core APIs.
If something goes wrong, then it's platform_get_irq() to blame, and
not the libahci_platform.

-- 
With Best Regards,
Andy Shevchenko