Message-ID: <9931f19a-31f7-d98a-1540-979e2db30eaf@gmail.com>
Date:   Sun, 19 Mar 2023 16:28:35 +0200
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Subject: Re: [PATCH v3 2/6] iio: light: Add gain-time-scale helpers
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To:     Jonathan Cameron <jic23@kernel.org>,
        "Vaittinen, Matti" <Matti.Vaittinen@fi.rohmeurope.com>
Cc:     Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Shreeya Patel <shreeya.patel@collabora.com>,
        Paul Gazzillo <paul@pgazz.com>,
        Dmitry Osipenko <dmitry.osipenko@collabora.com>,
        Zhigang Shi <Zhigang.Shi@liteon.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-iio@vger.kernel.org" <linux-iio@vger.kernel.org>
References: <cover.1678093787.git.mazziesaccount@gmail.com>
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 <ZAXiKfRbsXpHhwAJ@smile.fi.intel.com> <20230312165100.45de0c9b@jic23-huawei>
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 <ZA8ho4YfhBkSMFxS@smile.fi.intel.com>
 <d2986a9e-c516-ea6d-8f94-5cd4723312bd@fi.rohmeurope.com>
 <20230318171751.75911d26@jic23-huawei>
From:   Matti Vaittinen <mazziesaccount@gmail.com>
In-Reply-To: <20230318171751.75911d26@jic23-huawei>
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On 3/18/23 19:17, Jonathan Cameron wrote:
> On Tue, 14 Mar 2023 06:19:35 +0000
> "Vaittinen, Matti" <Matti.Vaittinen@fi.rohmeurope.com> wrote:
> 
>> On 3/13/23 15:14, Andy Shevchenko wrote:
>>> On Mon, Mar 13, 2023 at 02:56:59PM +0200, Matti Vaittinen wrote:
>>>> On 3/12/23 18:51, Jonathan Cameron wrote:
>>>>> On Mon, 6 Mar 2023 14:52:57 +0200
>>>>> Andy Shevchenko <andriy.shevchenko@linux.intel.com> wrote:
>>>>>> On Mon, Mar 06, 2023 at 11:17:15AM +0200, Matti Vaittinen wrote:
>>>
>>> ...
>>>    
>>>>>>> +EXPORT_SYMBOL_NS_GPL(iio_gts_total_gain_to_scale, IIO_GTS_HELPER);
>>>>>>
>>>>>> I would say _HELPER part is too much, but fine with me.
>>>>>
>>>>> Hmm. I think I like the HELPER bit as separates it from being a driver.
>>>>> Of course I might change my mind after a few sleeps.
>>>>
>>>> Ever considered a career as a politician? ;) (No offense intended - and feel
>>>> free to change your mind on this. I don't expect this to be done tomorrow)
>>>
>>> It will be a one liner in the provider if you use DEFAULT_SYMBOL_NAMESPACE
>>> definition.
>>
>> Oh. I didn't know about DEFAULT_SYMBOL_NAMESPACE - or if I did, I had
>> forgot it. My memory has never been great and seems to be getting worse
>> all the time...
> 
>>
>> I don't know what to think of this define though. I can imagine that
>> someone who is not familiar with it could be very confused as to why the
>> symbols are not found even though EXPORT_SYMBOL or EXPORT_SYMBOL_GPL are
>> used. OTOH, I think I once saw an error about symbols being in a
>> namespace (when trying to use one without the namespace). This should
>> probably just be a good enough hint for finding out what's going on.
>>
>> Luckily, I think all the exports in this case were oneliners even with
>> the namespace explicitly spelled. Well, I think that for one or two
>> exports the semicolon did slip to col 81 or 82 - but I am not sure if
>> fixing this weighs more than the clarity of explicitly showing the
>> namespace in export.
>>
>> Well, I guess I can go with either of these ways - do you have a strong
>> opinion on using the DEFAULT_SYMBOL_NAMESPACE?
>>
> 
> If it's in the C file, then I can cope with doing it this way.
> Don't do it in the compiler options though.  That got ripped out of CXL
> because it was considered a bad idea to hide the namespace away like that.
> 
> Personally I prefer the namespace of the symbols explicit in each export
> as they are easy to find that way.

I share the same view on this. I did use the DEFAULT_SYMBOL_NAMESPACE 
for v4 - but I'll drop that for v5 and go back with the explicit 
name-space usage.

Yours,
	-- Matti

-- 
Matti Vaittinen
Linux kernel developer at ROHM Semiconductors
Oulu Finland

~~ When things go utterly wrong vim users can always type :help! ~~