netdev - Re: [PATCH v2 1/2] platform: make platform_get_irq

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Message-ID: <20220214140027.npw6ddrxklarb6wp@pengutronix.de>
Date:   Mon, 14 Feb 2022 15:00:27 +0100
From:   Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
To:     Geert Uytterhoeven <geert@...ux-m68k.org>
Cc:     Andrew Lunn <andrew@...n.ch>, Ulf Hansson <ulf.hansson@...aro.org>,
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Subject: Re: [PATCH v2 1/2] platform: make platform_get_irq_optional()
 optional

Hello Geert,

On Mon, Feb 14, 2022 at 10:01:14AM +0100, Geert Uytterhoeven wrote:
> Also IMHO, the dummy value handling is a red herring.  Contrary to
> optional clocks and resets, a missing optional interrupt does not
> always mean there is nothing to do: in case of polling, something
> else must definitely be done. 

Note this is exactly why I don't like this change. I'd even go so far
and claim that "a missing optional interrupt hardly ever means there is
nothing to do".

> So even if request_irq() would accept a dummy interrupt zero and just
> do nothing, it would give the false impression that that is all there
> is to do, while an actual check for zero with polling code handling
> may still need to be present, thus leading to more not less bugs.

Yes, a dummy irq value will just not be possible.

Best regards
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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