linux-kernel - Re: [PATCH v3 15/19] hwmon: (mr75203) add support for series 6 temperature equation

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Message-ID: <7b4baf42-eb8e-ad83-a259-a4a0e4e4ac01@amazon.com>
Date:   Thu, 1 Sep 2022 15:14:02 +0300
From:   "Farber, Eliav" <farbere@...zon.com>
To:     Andy Shevchenko <andriy.shevchenko@...el.com>
CC:     <jdelvare@...e.com>, <linux@...ck-us.net>, <robh+dt@...nel.org>,
        <p.zabel@...gutronix.de>, <rtanwar@...linear.com>,
        <linux-hwmon@...r.kernel.org>, <devicetree@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>, <talel@...zon.com>,
        <hhhawa@...zon.com>, <jonnyc@...zon.com>, <hanochu@...zon.com>,
        <ronenk@...zon.com>, <itamark@...zon.com>, <shellykz@...zon.com>,
        <shorer@...zon.com>, <amitlavi@...zon.com>, <almogbs@...zon.com>,
        <dkl@...zon.com>, "Farber, Eliav" <farbere@...zon.com>
Subject: Re: [PATCH v3 15/19] hwmon: (mr75203) add support for series 6 temperature
 equation

On 8/31/2022 3:08 PM, Andy Shevchenko wrote:
> On Tue, Aug 30, 2022 at 07:22:08PM +0000, Eliav Farber wrote:
>> The current equation used in code is aligned to series 5:
>> T = G + H * (n / cal5 - 0.5) + J * F
>> Where:
>> G = 60, H = 200, cal5 = 4094, J = -0.1, F = frequency clock in MHz
>>
>> Series 6 has a slightly different equation:
>> T = G + H * (n / cal5 - 0.5)
>> and a different set of coefficients:
>> G = 57.4, H = 249.4, cal5 = 4096
>>
>> This change supports equation and coefficients for both series.
>> (for series 6, J is set to 0).
>>
>> The series is determined according to “ts-series” property in device
>> tree.
>> If absent, series 5 is assumed to be the default.
>
> ...
>
>> -#define PVT_H_CONST          200000
>> -#define PVT_G_CONST          60000
>> -#define PVT_J_CONST          -100
>> -#define PVT_CAL5_CONST               4094
>
> You just introduced them patch before. Please, avoid ping-pong style in
> the same series.


Fixed for v4.
I now introduce these defines in patch 13 to avoid modifying the above
ones and then remove them:
/* Temperature coefficients for series 5 */
#define PVT_SERIES5_H_CONST    200000
#define PVT_SERIES5_G_CONST    60000
#define PVT_SERIES5_J_CONST    -100
#define PVT_SERIES5_CAL5_CONST    4094

> ...
>
>> +     ret = of_property_read_u32(np, "moortec,ts-series", &series);
>
> of_ ?!
>
> Be consistent. Either you use OF everywhere, or device property APIs.
>

Fixed for v4.
Using device_property_read_u32() instead.

> ...
>
>> +     if (ret)
>> +             series = TEMPERATURE_SENSOR_SERIES_5;
>> +
>> +     if (series == TEMPERATURE_SENSOR_SERIES_5) {
>> +             ts_coeff->h = PVT_SERIES5_H_CONST;
>> +             ts_coeff->g = PVT_SERIES5_G_CONST;
>> +             ts_coeff->j = PVT_SERIES5_J_CONST;
>> +             ts_coeff->cal5 = PVT_SERIES5_CAL5_CONST;
>> +     } else if (series == TEMPERATURE_SENSOR_SERIES_6) {
>> +             ts_coeff->h = PVT_SERIES6_H_CONST;
>> +             ts_coeff->g = PVT_SERIES6_G_CONST;
>> +             ts_coeff->j = PVT_SERIES6_J_CONST;
>> +             ts_coeff->cal5 = PVT_SERIES6_CAL5_CONST;
>> +     } else {
>> +             dev_err(dev, "invalid temperature sensor series (%u)\n",
>> +                     series);
>> +             return -EINVAL;
>> +     }
>
> switch-case? 

Changed to switch-case (will be part of v4).

--
Thanks, Eliav