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Date:   Fri, 20 Jan 2023 19:08:20 +0100
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Subject: Re: [PATCH v5 1/3] thermal/acpi: Add ACPI trip point routines
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To:     "Rafael J. Wysocki" <rafael@kernel.org>
Cc:     srinivas.pandruvada@linux.intel.com, linux-pm@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org,
        rui.zhang@intel.com, christophe.jaillet@wanadoo.fr
References: <20230113180235.1604526-1-daniel.lezcano@linaro.org>
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From:   Daniel Lezcano <daniel.lezcano@linaro.org>
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Hi Rafael,


On 19/01/2023 14:15, Rafael J. Wysocki wrote:

[ ... ]

>> +static int thermal_acpi_get_temperature_object(struct acpi_device *adev,
>> +                                              char *object, int *temperature)
> 
> So this would become thermal_acpi_get_temp_object(). or even
> thermal_acpi_get_temp() because it really returns the temperature
> value.
> 
> I also don't particularly like returning values via pointers, which is
> entirely avoidable here, because the temperature value obtained from
> the ACPI control methods must be a positive number.
> 
> So I would make it
> 
> static int thermal_acpi_get_temp(struct acpi_device *adev, char *object_name)
> {

We are converting decikelvin -> millicelsius. Even it is very unlikely, 
the result could be less than zero (eg. -1°C). We won't be able to 
differentiate -ENODATA with a negative value, no ?

In the future, it is possible we will have to deal with cold trip points 
in order to warm a board. May be we should don't care for now ?


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