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Message-ID: <62a262a1-b945-ad4f-fdb8-d05fcba882d3@rasmusvillemoes.dk>
Date:   Fri, 23 Sep 2022 10:40:06 +0200
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Subject: Re: [PATCH v2 9/9] rtc: isl12022: add support for temperature sensor
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To:     Guenter Roeck <linux@roeck-us.net>,
        Alessandro Zummo <a.zummo@towertech.it>,
        Alexandre Belloni <alexandre.belloni@bootlin.com>,
        Jean Delvare <jdelvare@suse.com>
Cc:     linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-hwmon@vger.kernel.org
References: <20220830100152.698506-1-linux@rasmusvillemoes.dk>
 <20220921114624.3250848-1-linux@rasmusvillemoes.dk>
 <20220921114624.3250848-10-linux@rasmusvillemoes.dk>
 <8cb2bac1-3a03-09a1-c071-96ca4a95fa44@roeck-us.net>
From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
In-Reply-To: <8cb2bac1-3a03-09a1-c071-96ca4a95fa44@roeck-us.net>
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On 21/09/2022 16.13, Guenter Roeck wrote:
> On 9/21/22 04:46, Rasmus Villemoes wrote:

>> +static int isl12022_hwmon_read(struct device *dev,
>> +                   enum hwmon_sensor_types type,
>> +                   u32 attr, int channel, long *val)
>> +{
>> +    if (type == hwmon_chip && attr == hwmon_chip_update_interval) {
>> +        *val = 60000;
>> +        return 0;
>> +    }
> 
> It is not the purpose of the update_interval attribute to inform the
> user what the update interval of this chip happens to be. The purpose
> of the attribute is to inform the chip what update interval it should use.

Well, I think it's a completely natural thing to expose a fixed and
known update_interval as a 0444 property, and it might even be useful to
userspace to know that there's no point reading the sensor any more
often than that. And I didn't come up with this by myself, there's
already at least a couple of instances of a 0444 update_interval.

I'll leave it to the RTC maintainers to decide, it's easy enough to remove.

Rasmus