Date:   Thu, 13 Jan 2022 13:42:57 -0800
From:   Florian Fainelli <f.fainelli@...il.com>
To:     Uwe Kleine-König <u.kleine-koenig@...gutronix.de>,
        Mark Brown <broonie@...nel.org>
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Subject: Re: [PATCH] driver core: platform: Rename platform_get_irq_optional()
 to platform_get_irq_silent()



On 1/13/2022 11:43 AM, Uwe Kleine-König wrote:
> The subsystems regulator, clk and gpio have the concept of a dummy
> resource. For regulator, clk and gpio there is a semantic difference
> between the regular _get() function and the _get_optional() variant.
> (One might return the dummy resource, the other won't. Unfortunately
> which one implements which isn't the same for these three.) The
> difference between platform_get_irq() and platform_get_irq_optional() is
> only that the former might emit an error message and the later won't.
> 
> To prevent people's expectations that there is a semantic difference
> between these too, rename platform_get_irq_optional() to
> platform_get_irq_silent() to make the actual difference more obvious.
> 
> The #define for the old name can and should be removed once all patches
> currently in flux still relying on platform_get_irq_optional() are
> fixed.
> 
> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@...gutronix.de>
> ---
> Hello,
> 
> On Thu, Jan 13, 2022 at 02:45:30PM +0000, Mark Brown wrote:
>> On Thu, Jan 13, 2022 at 12:08:31PM +0100, Uwe Kleine-König wrote:
>>
>>> This is all very unfortunate. In my eyes b) is the most sensible
>>> sense, but the past showed that we don't agree here. (The most annoying
>>> part of regulator_get is the warning that is emitted that regularily
>>> makes customers ask what happens here and if this is fixable.)
>>
>> Fortunately it can be fixed, and it's safer to clearly specify things.
>> The prints are there because when the description is wrong enough to
>> cause things to blow up we can fail to boot or run messily and
>> forgetting to describe some supplies (or typoing so they haven't done
>> that) and people were having a hard time figuring out what might've
>> happened.
> 
> Yes, that's right. I sent a patch for such a warning in 2019 and pinged
> occationally. Still waiting for it to be merged :-\
> (https://lore.kernel.org/r/20190625100412.11815-1-u.kleine-koenig@pengutronix.de)
> 
>>> I think at least c) is easy to resolve because
>>> platform_get_irq_optional() isn't that old yet and mechanically
>>> replacing it by platform_get_irq_silent() should be easy and safe.
>>> And this is orthogonal to the discussion if -ENOXIO is a sensible return
>>> value and if it's as easy as it could be to work with errors on irq
>>> lookups.
>>
>> It'd certainly be good to name anything that doesn't correspond to one
>> of the existing semantics for the API (!) something different rather
>> than adding yet another potentially overloaded meaning.
> 
> It seems we're (at least) three who agree about this. Here is a patch
> fixing the name.

 From an API naming perspective this does not make much sense anymore 
with the name chosen, it is understood that whent he function is called 
platform_get_irq_optional(), optional applies to the IRQ. An optional 
IRQ is something people can reason about because it makes sense.

What is a a "silent" IRQ however? It does not apply to the object it is 
trying to fetch to anymore, but to the message that may not be printed 
in case the resource failed to be obtained, because said resource is 
optional. Woah, that's quite a stretch.

Following the discussion and original 2 patches set from Sergey, it is 
not entirely clear to me anymore what is it that we are trying to fix.

I nearly forgot, I would paint it blue, sky blue, not navy blue, not 
light blue ;)
-- 
Florian

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