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Date:   Wed, 26 Jul 2023 09:10:33 -0700
From:   Nathan Chancellor <nathan@kernel.org>
To:     Okan Sahin <okan.sahin@analog.com>
Cc:     Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        Ibrahim Tilki <Ibrahim.Tilki@analog.com>,
        linux-kernel@vger.kernel.org, devicetree@vger.kernel.org,
        llvm@lists.linux.dev
Subject: Re: [PATCH v3 2/2] regulator: max77857: Add ADI MAX77857/59/MAX77831
 Regulator Support
Message-ID: <20230726161033.GA1102409@dev-arch.thelio-3990X>
References: <20230717050736.10075-1-okan.sahin@analog.com>
 <20230717050736.10075-3-okan.sahin@analog.com>
 <20230718155502.GA3542993@dev-arch.thelio-3990X>
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Hi Okan,

On Tue, Jul 18, 2023 at 08:55:02AM -0700, Nathan Chancellor wrote:

<snip>

> > +static struct regulator_desc max77857_regulator_desc = {
> > +	.ops = &max77857_regulator_ops,
> > +	.name = "max77857",
> > +	.linear_ranges = max77857_lin_ranges,
> > +	.n_linear_ranges = ARRAY_SIZE(max77857_lin_ranges),
> > +	.vsel_mask = 0xFF,
> > +	.vsel_reg = MAX77857_REG_CONT2,
> > +	.ramp_delay_table = max77857_ramp_table[0],
> > +	.n_ramp_values = ARRAY_SIZE(max77857_ramp_table[0]),
> > +	.ramp_reg = MAX77857_REG_CONT3,
> > +	.ramp_mask = GENMASK(1, 0),
> > +	.ramp_delay = max77857_ramp_table[0][0],
> 
> This breaks the build with GCC 5.x through 7.x:
> 
>   drivers/regulator/max77857-regulator.c:312:16: error: initializer element is not constant
>     .ramp_delay = max77857_ramp_table[0][0],
>                   ^~~~~~~~~~~~~~~~~~~
>   drivers/regulator/max77857-regulator.c:312:16: note: (near initialization for 'max77857_regulator_desc.ramp_delay')
> 
> and clang:
> 
>   drivers/regulator/max77857-regulator.c:312:16: error: initializer element is not a compile-time constant
>     312 |         .ramp_delay = max77857_ramp_table[0][0],
>         |                       ^~~~~~~~~~~~~~~~~~~~~~~~~
>   1 error generated.
> 
> This relies on a GCC 8.x+ change that accepts more things as
> compile-time constants, which is being worked on in clang
> (https://reviews.llvm.org/D76096). Since the kernel supports older
> compilers, this will have to be worked around somehow. Perhaps a define
> that can be used in both places?

Was there any update on this? I do not mind sending a patch for this
myself if I have some sort of guidance on how you would prefer for this
to be fixed, should you be too busy to look into it.

Cheers,
Nathan