Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Tue, 12 Mar 2019 10:48:46 -0500
From:   Rob Herring <robh@kernel.org>
To:     Stefan Wahren <stefan.wahren@i2se.com>
Cc:     Kamil Debski <kamil@wypas.org>,
        Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
        Jean Delvare <jdelvare@suse.com>,
        Guenter Roeck <linux@roeck-us.net>,
        Mark Rutland <mark.rutland@arm.com>,
        linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH RFC V2 1/3] dt-bindings: hwmon: Add tachometer interrupt
 to pwm-fan
Message-ID: <20190312154846.GA11788@bogus>
References: <1551110359-19860-1-git-send-email-stefan.wahren@i2se.com>
 <1551110359-19860-2-git-send-email-stefan.wahren@i2se.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <1551110359-19860-2-git-send-email-stefan.wahren@i2se.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Mon, Feb 25, 2019 at 04:59:17PM +0100, Stefan Wahren wrote:
> This adds the tachometer interrupt to the pwm-fan binding, which is
> necessary for RPM support.
> 
> Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
> ---
>  Documentation/devicetree/bindings/hwmon/pwm-fan.txt | 19 +++++++++++++++++++
>  1 file changed, 19 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
> index 49ca5d8..7d09623 100644
> --- a/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
> +++ b/Documentation/devicetree/bindings/hwmon/pwm-fan.txt
> @@ -8,6 +8,14 @@ Required properties:
>  
>  Optional properties:
>  - fan-supply    : phandle to the regulator that provides power to the fan
> +- interrupts      : This contains a single interrupt specifier which
> +		    describes the tachometer output of the fan as an
> +		    interrupt source. The output signal must generate a
> +		    defined number of interrupts per fan revolution, which
> +		    require that it must be self resetting edge interrupts.
> +		    See interrupt-controller/interrupts.txt for the format.
> +- interrupt-ratio : defines the ratio interrupts per fan revolution as an
> +		    integer (default is 2 interrupts per revolution)

Name this for what it is, not how it is used. Using 'interrupt' is 
misleading that it is related to the interrupt binding.
'tach-pulse-per-rev' or something similar.

>  
>  Example:
>  	fan0: pwm-fan {
> @@ -38,3 +46,14 @@ Example:
>  					};
>  			     };
>  		};
> +
> +Example 2:
> +	fan0: pwm-fan {
> +		fan0: pwm-fan {
> +		compatible = "pwm-fan";
> +		pwms = <&pwm 0 40000 0>;
> +		fan-supply = <&reg_fan>;
> +		interrupt-parent = <&gpio5>;
> +		interrupts = <1 IRQ_TYPE_EDGE_FALLING>;
> +		interrupt-ratio = <2>;
> +	};
> -- 
> 2.7.4
>