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Date:   Thu, 19 Jan 2023 20:54:01 +0000
From:   Lee Jones <lee@kernel.org>
To:     Rob Herring <robh@kernel.org>
Cc:     Jesse Taube <mr.bossman075@gmail.com>,
        linux-kernel@vger.kernel.org, linux-input@vger.kernel.org,
        lee.jones@linaro.org
Subject: Re: [PATCH v2] drivers/mfd: simple-mfd-i2c: Add generic compatible
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References: <20221202113226.114465-1-Mr.Bossman075@gmail.com>
 <20230119175135.GA2085792-robh@kernel.org>
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On Thu, 19 Jan 2023, Rob Herring wrote:

> On Fri, Dec 02, 2022 at 06:32:26AM -0500, Jesse Taube wrote:
> > Some devices may want to use this driver without having a specific
> > compatible string. Add a generic compatible string to allow this.
> 
> What devices need this?
> 
> Is that no specific compatible string at all or just in the kernel? 
> Because the former definitely goes against DT requirements. The latter 
> enables the former without a schema.
> 
> > 
> > Signed-off-by: Jesse Taube <Mr.Bossman075@gmail.com>
> > ---
> >  drivers/mfd/simple-mfd-i2c.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/mfd/simple-mfd-i2c.c b/drivers/mfd/simple-mfd-i2c.c
> > index f4c8fc3ee463..0bda0dd9276e 100644
> > --- a/drivers/mfd/simple-mfd-i2c.c
> > +++ b/drivers/mfd/simple-mfd-i2c.c
> > @@ -73,6 +73,7 @@ static const struct simple_mfd_data silergy_sy7636a = {
> >  };
> >  
> >  static const struct of_device_id simple_mfd_i2c_of_match[] = {
> > +	{ .compatible = "simple-mfd-i2c-generic" },
> 
> Simple and generic? There is no such device. Anywhere.
> 
> This is also not documented which is how I found it (make 
> dt_compatible_check). But this should be reverted or dropped rather than 
> documented IMO.

I thought it would be better than having a huge list here.

Devices should *also* be allocated a specific compatible string.

$ git grep simple-mfd -- arch

-- 
Lee Jones [李琼斯]