linux-kernel - Re: [PATCH-v2 2/2] regulator: 88pm800: Add support for configuration of dual phase on BUCK1

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Message-ID: <CAJKOXPcMd9VvfA48kaBa0BYeHAfHTu6MzAbQv0HuRy9wbgz0wg@mail.gmail.com>
Date:	Thu, 23 Jul 2015 13:51:26 +0900
From:	Krzysztof Kozlowski <k.kozlowski@...sung.com>
To:	Vaibhav Hiremath <vaibhav.hiremath@...aro.org>
Cc:	linux-arm-kernel@...ts.infradead.org, devicetree@...r.kernel.org,
	Krzysztof Kozlowski <k.kozlowski@...sung.com>,
	linux-kernel@...r.kernel.org, robh+dt@...nel.org,
	broonie@...nel.org, lee.jones@...aro.org
Subject: Re: [PATCH-v2 2/2] regulator: 88pm800: Add support for configuration
 of dual phase on BUCK1

2015-07-22 1:23 GMT+09:00 Vaibhav Hiremath <vaibhav.hiremath@...aro.org>:
> 88PM860 device supports dual phase mode on BUCK1 output.
> In normal usecase, BUCK1A and BUCK1B operates independently with 3A
> capacity. And they both can work as a dual phase providing 6A capacity.
>
> This patch updates the regulator driver to read the respective
> DT property and enable dual-phase mode on BUCK1.
>
> Note that, this is init time (one time) initialization.
>
> Signed-off-by: Vaibhav Hiremath <vaibhav.hiremath@...aro.org>
> ---
>  drivers/regulator/88pm800.c | 31 +++++++++++++++++++++++++++++++
>  include/linux/mfd/88pm80x.h |  3 +++
>  2 files changed, 34 insertions(+)

Don't you need to update the constraints also? I think the BUCK1
regulator has fixed constraint of 3 A:
  PM800_BUCK(buck1, BUCK1, BUCK_ENA, 0, 3000000, buck1_volt_range, 0x55),
and now it can handle 6 A.

>
> diff --git a/drivers/regulator/88pm800.c b/drivers/regulator/88pm800.c
> index e846e4c..1bf2b35 100644
> --- a/drivers/regulator/88pm800.c
> +++ b/drivers/regulator/88pm800.c
> @@ -267,6 +267,31 @@ static struct pm800_regulator_info pm860_regulator_info[] = {
>         PM800_LDO(ldo20, LDO20, LDO_ENA1_3, 3, 10000, ldo_volt_table2),
>  };
>
> +static int pm800_regulator_init(struct platform_device *pdev)
> +{
> +       struct pm800_regulators *pm800_data = platform_get_drvdata(pdev);
> +       struct pm80x_chip *chip = pm800_data->chip;
> +       int ret;

'ret' is used only in if statement below. I don't have strong feelings
but can you move it there to limit its scope or always return 'ret'
(after initializing to '0'). To me this would be more readable.

Best regards,
Krzysztof

> +
> +       /* Currently only supported on 88pm860 device */
> +       if (chip->type != CHIP_PM860)
> +               return 0;
> +
> +       if (of_property_read_bool(pdev->dev.of_node,
> +                               "marvell,88pm860-buck1-dualphase-en")) {
> +               ret = regmap_update_bits(chip->subchip->regmap_power,
> +                                       PM860_BUCK1_MISC,
> +                                       BUCK1_DUAL_PHASE_SEL,
> +                                       BUCK1_DUAL_PHASE_SEL);
> +               if (ret) {
> +                       dev_err(chip->dev, "failed to set dual-pase mode %d\n", ret);
> +                       return ret;
> +               }
> +       }
> +
> +       return 0;
> +}
> +
>  static int pm800_regulator_probe(struct platform_device *pdev)
>  {
>         struct pm80x_chip *chip = dev_get_drvdata(pdev->dev.parent);
> @@ -336,6 +361,12 @@ static int pm800_regulator_probe(struct platform_device *pdev)
>                 }
>         }
>
> +       ret = pm800_regulator_init(pdev);
> +       if (ret) {
> +               dev_err(&pdev->dev, "failed to init 88pm800 regulator device\n");
> +               return ret;
> +       }
> +
>         return 0;
>  }
>
> diff --git a/include/linux/mfd/88pm80x.h b/include/linux/mfd/88pm80x.h
> index a92d173..05d9bad 100644
> --- a/include/linux/mfd/88pm80x.h
> +++ b/include/linux/mfd/88pm80x.h
> @@ -295,6 +295,9 @@ enum {
>  #define PM860_BUCK4_MISC2              (0x82)
>  #define PM860_BUCK4_FULL_DRV           BIT(2)
>
> +#define PM860_BUCK1_MISC               (0x8E)
> +#define BUCK1_DUAL_PHASE_SEL           BIT(2)
> +
>  struct pm80x_rtc_pdata {
>         int             vrtc;
>         int             rtc_wakeup;
> --
> 1.9.1
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@...ts.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
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