netdev - Re: [PATCH 1/2] platform: make platform_get_irq

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Date:   Wed, 19 Jan 2022 22:49:52 +0300
From:   Sergey Shtylyov <s.shtylyov@....ru>
To:     Andy Shevchenko <andriy.shevchenko@...ux.intel.com>,
        Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
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Subject: Re: [PATCH 1/2] platform: make platform_get_irq_optional() optional

On 1/19/22 9:58 PM, Andy Shevchenko wrote:

[...]
>> Because with your change we have:
>>
>>  - < 0 -> error
>>  - == 0 -> no irq
>>  - > 0 -> irq
>>
>> For my part I'd say this doesn't justify the change, but at least I
>> could better life with the reasoning. If you start at:
>>
>> 	irq = platform_get_irq_optional(...)
>> 	if (irq < 0 && irq != -ENXIO)
>> 		return irq
>> 	else if (irq > 0)
>> 		setup_irq(irq);
>> 	else
>> 		setup_polling()
>>
>> I'd change that to
>>
>> 	irq = platform_get_irq_optional(...)
>> 	if (irq > 0) /* or >= 0 ? */
>> 		setup_irq(irq)
>> 	else if (irq == -ENXIO)
>> 		setup_polling()
>> 	else
>> 		return irq
>>
>> This still has to mention -ENXIO, but this is ok and checking for 0 just
>> hardcodes a different return value.
> 
> It's what we are against of. The idea is to have
> 
> 	irq = platform_get_irq_optional(...)
> 	if (irq < 0) // we do not care about special cookies here
> 		return irq;
> 
> 	if (irq)
> 		setup_irq(irq)
> 	else
> 		setup_polling()
> 
> See the difference? Your code is convoluted.

   ... and it's longer when you look at the translated code! :-)

[...]

MBR, Sergey