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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Thu, 23 Jun 2022 20:25:48 +0200
Message-ID: <CAHp75VexwvAVeY4MtwKfpNY96eJ1C9eqadd-L+20O2sg2+gYNg@mail.gmail.com>
Subject: Re: [PATCH v3 10/14] iio: adc: mt6370: Add Mediatek MT6370 support
To:     ChiaEn Wu <peterwu.pub@gmail.com>
Cc:     Lee Jones <lee.jones@linaro.org>,
        Daniel Thompson <daniel.thompson@linaro.org>,
        Jingoo Han <jingoohan1@gmail.com>, Pavel Machek <pavel@ucw.cz>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Matthias Brugger <matthias.bgg@gmail.com>,
        Sebastian Reichel <sre@kernel.org>,
        Chunfeng Yun <chunfeng.yun@mediatek.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jonathan Cameron <jic23@kernel.org>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Liam Girdwood <lgirdwood@gmail.com>,
        Mark Brown <broonie@kernel.org>,
        Guenter Roeck <linux@roeck-us.net>,
        "Krogerus, Heikki" <heikki.krogerus@linux.intel.com>,
        Helge Deller <deller@gmx.de>, chiaen_wu@richtek.com,
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On Thu, Jun 23, 2022 at 2:00 PM ChiaEn Wu <peterwu.pub@gmail.com> wrote:
>
> From: ChiaEn Wu <chiaen_wu@richtek.com>
>
> Add Mediatek MT6370 ADC support.

...

> +config MEDIATEK_MT6370_ADC
> +       tristate "Mediatek MT6370 ADC driver"
> +       depends on MFD_MT6370
> +       help
> +         Say yes here to enable Mediatek MT6370 ADC support.
> +
> +         This ADC driver provides 9 channels for system monitoring (charger
> +         current, voltage, and temperature).

What will be the module name?

...

> +#include <dt-bindings/iio/adc/mediatek,mt6370_adc.h>

Usually this goes after linux/* asm/* as it's not so generic.

> +#include <linux/bits.h>
> +#include <linux/bitfield.h>
> +#include <linux/iio/iio.h>
> +#include <linux/kernel.h>
> +#include <linux/module.h>

> +#include <linux/mod_devicetable.h>

I believe the order should be otherwise, this is first followed by module.h.

> +#include <linux/mutex.h>
> +#include <linux/platform_device.h>
> +#include <linux/regmap.h>

...

> +#define ADC_CONV_POLLING_TIME          1000

If it's time, add a unit suffix, if it's a counter, make it clear.

...

> +       msleep(ADC_CONV_TIME_US / 1000);

Why define microseconds if milliseconds are in use?

...

> +       ret = regmap_read_poll_timeout(priv->regmap,
> +                                      MT6370_REG_CHG_ADC, reg_val,
> +                                      !(reg_val & MT6370_ADC_START_MASK),
> +                                      ADC_CONV_POLLING_TIME,
> +                                      ADC_CONV_TIME_US * 3);
> +       if (ret) {
> +               if (ret == -ETIMEDOUT)
> +                       dev_err(priv->dev, "Failed to wait ADC conversion\n");

wait for

> +               else
> +                       dev_err(priv->dev,
> +                               "Failed to read ADC register (%d)\n", ret);

Do you really need to differentiate the errors here? I believe the
latter one covers all cases.

> +               goto adc_unlock;
> +       }

...

> +#define MT6370_ADC_CHAN(_idx, _type, _addr, _extra_info) {     \
> +       .type = _type,                                          \
> +       .channel = MT6370_CHAN_##_idx,                          \
> +       .address = _addr,                                       \
> +       .scan_index = MT6370_CHAN_##_idx,                       \
> +       .indexed = 1,                                           \
> +       .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |          \
> +                             BIT(IIO_CHAN_INFO_SCALE) |        \
> +                             _extra_info                       \

Leave a comma after the last member as well.

> +}

...

> +       regmap = dev_get_regmap(pdev->dev.parent, NULL);
> +       if (!regmap) {

> +               dev_err(&pdev->dev, "Failed to get regmap\n");
> +               return -ENODEV;

return dev_err_probe(...);

> +       }

...

> +       ret = regmap_write(priv->regmap, MT6370_REG_CHG_ADC, 0);
> +       if (ret) {
> +               dev_err(&pdev->dev, "Failed to reset ADC\n");
> +               return ret;
> +       }

Ditto.

-- 
With Best Regards,
Andy Shevchenko