Re: [v6 2/4] dt-bindings: hwmon: Add ASPEED TACH Control documentation

From: Guenter Roeck <linux@roeck-us.net>
To: 蔡承達 <billyking19920205@gmail.com>
Cc: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
	"jdelvare@suse.com" <jdelvare@suse.com>,
	"robh+dt@kernel.org" <robh+dt@kernel.org>,
	"krzysztof.kozlowski+dt@linaro.org" 
	<krzysztof.kozlowski+dt@linaro.org>,
	"joel@jms.id.au" <joel@jms.id.au>,
	"andrew@aj.id.au" <andrew@aj.id.au>,
	"thierry.reding@gmail.com" <thierry.reding@gmail.com>,
	"u.kleine-koenig@pengutronix.de" <u.kleine-koenig@pengutronix.de>,
	"corbet@lwn.net" <corbet@lwn.net>,
	"p.zabel@pengutronix.de" <p.zabel@pengutronix.de>,
	"linux-hwmon@vger.kernel.org" <linux-hwmon@vger.kernel.org>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>,
	"linux-aspeed@lists.ozlabs.org" <linux-aspeed@lists.ozlabs.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-pwm@vger.kernel.org" <linux-pwm@vger.kernel.org>,
	"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
	"patrick@stwcx.xyz" <patrick@stwcx.xyz>,
	Billy Tsai <billy_tsai@aspeedtech.com>
Subject: Re: [v6 2/4] dt-bindings: hwmon: Add ASPEED TACH Control documentation
Date: Fri, 14 Jul 2023 03:26:42 -0700	[thread overview]
Message-ID: <7b198d57-ddec-3074-314a-3e5e5b8f48f9@roeck-us.net> (raw)
In-Reply-To: <CAGUgbhC34-pUp4ECULc0ScaN7hUF1L-z69h+ji-TiVrv4gKd3Q@mail.gmail.com>

On 7/14/23 03:18, 蔡承達 wrote:
> Guenter Roeck <linux@roeck-us.net> 於 2023年7月14日 週五 下午5:59寫道：
>>
>> On 7/14/23 00:13, Krzysztof Kozlowski wrote:
>>> On 14/07/2023 09:04, 蔡承達 wrote:
>>>
>>>>           > This is because our register layout for PWM and Tach is not
>>>> continuous.
>>>>
>>>>           > PWM0 used 0x0 0x4, Tach0 used 0x8 0xc
>>>>
>>>>           > PWM1 used 0x10 0x14, Tach1 used 0x18 0x1c
>>>>
>>>>           > ...
>>>>
>>>>           > Each PWM/Tach instance has its own controller register and is not
>>>> dependent on others.
>>>
>>> Your email reply quoting style is very difficult to read.
>>>
>>>>
>>>>
>>>>
>>>> Hi Guenter,
>>>>
>>>>
>>>>
>>>> Did you receive a response to my previous email?
>>>>
>>>> I would like to inquire if you have any further concerns regarding the PWM
>>>> and Tach with 16 instances.
>>>
>>> But isn't like this in all PWMs in all SoCs?
>>>
>>
>> Correct, pretty much every fan controller is implemented that way.
>> I don't understand the logic.
>>
> 
> Hi Krzysztof and Guenter,
> 
> Apologies for any confusion earlier.
> So, you think that the implementation with 16 instances of TACH/PWM
> device nodes in dts instead of one is ok to you, right?
> 

Did I say that ? No, it is not ok with me. It is confusing and doesn't make
sense to me. This is one fan controller with 16 channels, not 16 separate
controllers.

Guenter