Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Wed, 15 Jul 2020 15:25:54 -0700
From:   Guenter Roeck <linux@roeck-us.net>
To:     Rob Herring <robh@kernel.org>
Cc:     "Daniel M. Weeks" <dan@danweeks.net>, jdelvare@suse.com,
        linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] dt-bindings: hwmon: Correct vendor for mcp980x
Message-ID: <20200715222554.GB231856@roeck-us.net>
References: <20200703153748.GA16156@dev.danweeks.net>
 <4884254c-4406-5c04-3df7-030541b7c201@roeck-us.net>
 <20200715214144.GB818608@bogus>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20200715214144.GB818608@bogus>
User-Agent: Mutt/1.9.4 (2018-02-28)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Wed, Jul 15, 2020 at 03:41:44PM -0600, Rob Herring wrote:
> On Fri, Jul 03, 2020 at 02:59:12PM -0700, Guenter Roeck wrote:
> > On 7/3/20 8:37 AM, Daniel M. Weeks wrote:
> > > Signed-off-by: Daniel M. Weeks <dan@danweeks.net>
> > > ---
> > >  Documentation/devicetree/bindings/hwmon/lm75.txt | 2 +-
> > >  drivers/hwmon/lm75.c                             | 8 ++++----
> > >  2 files changed, 5 insertions(+), 5 deletions(-)
> > > 
> > > diff --git a/Documentation/devicetree/bindings/hwmon/lm75.txt b/Documentation/devicetree/bindings/hwmon/lm75.txt
> > > index 273616702c51..e5bb554cd2c3 100644
> > > --- a/Documentation/devicetree/bindings/hwmon/lm75.txt
> > > +++ b/Documentation/devicetree/bindings/hwmon/lm75.txt
> > > @@ -14,10 +14,10 @@ Required properties:
> > >  		"maxim,max6626",
> > >  		"maxim,max31725",
> > >  		"maxim,max31726",
> > > -		"maxim,mcp980x",
> > >  		"nxp,pct2075",
> > >  		"st,stds75",
> > >  		"st,stlm75",
> > > +		"microchip,mcp980x",
> > >  		"microchip,tcn75",
> > >  		"ti,tmp100",
> > >  		"ti,tmp101",
> > > diff --git a/drivers/hwmon/lm75.c b/drivers/hwmon/lm75.c
> > > index ba0be48aeadd..a8cfc7e4a685 100644
> > > --- a/drivers/hwmon/lm75.c
> > > +++ b/drivers/hwmon/lm75.c
> > > @@ -690,10 +690,6 @@ static const struct of_device_id __maybe_unused lm75_of_match[] = {
> > >  		.compatible = "maxim,max31726",
> > >  		.data = (void *)max31725
> > >  	},
> > > -	{
> > > -		.compatible = "maxim,mcp980x",
> > > -		.data = (void *)mcp980x
> > > -	},
> > >  	{
> > >  		.compatible = "nxp,pct2075",
> > >  		.data = (void *)pct2075
> > > @@ -706,6 +702,10 @@ static const struct of_device_id __maybe_unused lm75_of_match[] = {
> > >  		.compatible = "st,stlm75",
> > >  		.data = (void *)stlm75
> > >  	},
> > > +	{
> > > +		.compatible = "microchip,mcp980x",
> > > +		.data = (void *)mcp980x
> > 
> > Hmm, makes me wonder if we should replace this with correct chip names
> > since we are at it. After all, it only includes mcp980{0,1,2,3} and not mcp9805.
> > 
> > Rob, any thoughts ?
> 
> Do we need to distinguish the chips? Aren't there existing users?
> 

We don't specifically need to distinguish mcp908[0123], but "x"
does not represent [0-9], only [0-3]. This driver does not support
mcp9805, for example. I don't know how this kind of situation is
handled in other drivers.

Looks like there are no existing in-kernel users. The initial entry for
mcp980x was added back in 2008, with no DT support in mind.
"maxim,mcp980x" was added with of_device_id table in 2017, with no one
(including me) realizing that this is not a Maxim chip.

Guenter