Re: [PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get_voltage()

From: Jonathan Cameron <jic23@kernel.org>
To: David Lechner <dlechner@baylibre.com>
Cc: Jonathan Corbet <corbet@lwn.net>,
	Liam Girdwood <lgirdwood@gmail.com>,
	Mark Brown <broonie@kernel.org>, Jean Delvare <jdelvare@suse.com>,
	Guenter Roeck <linux@roeck-us.net>,
	Support Opensource <support.opensource@diasemi.com>,
	Cosmin Tanislav <cosmin.tanislav@analog.com>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Michael Hennerich <Michael.Hennerich@analog.com>,
	Antoniu Miclaus <antoniu.miclaus@analog.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org,
	linux-hwmon@vger.kernel.org, linux-iio@vger.kernel.org,
	linux-staging@lists.linux.dev, linux-input@vger.kernel.org
Subject: Re: [PATCH RFC 3/7] hwmon: (da9052) Use devm_regulator_get_enable_get_voltage()
Date: Thu, 28 Mar 2024 14:20:38 +0000	[thread overview]
Message-ID: <20240328142038.33ad68bc@jic23-huawei> (raw)
In-Reply-To: <20240327-regulator-get-enable-get-votlage-v1-3-5f4517faa059@baylibre.com>

On Wed, 27 Mar 2024 18:18:52 -0500
David Lechner <dlechner@baylibre.com> wrote:

> We can reduce boilerplate code by using
> devm_regulator_get_enable_get_voltage().
> 
> Signed-off-by: David Lechner <dlechner@baylibre.com>

A few comments inline, but nothing substantial.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
> ---
>  drivers/hwmon/da9052-hwmon.c | 33 +++++++--------------------------
>  1 file changed, 7 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/hwmon/da9052-hwmon.c b/drivers/hwmon/da9052-hwmon.c
> index 2bd7ae8100d7..70e7bc72e980 100644
> --- a/drivers/hwmon/da9052-hwmon.c
> +++ b/drivers/hwmon/da9052-hwmon.c
> @@ -26,7 +26,6 @@ struct da9052_hwmon {
>  	struct mutex		hwmon_lock;
>  	bool			tsi_as_adc;
>  	int			tsiref_mv;
> -	struct regulator	*tsiref;
>  	struct completion	tsidone;
>  };
>  
> @@ -414,32 +413,19 @@ static int da9052_hwmon_probe(struct platform_device *pdev)
>  		device_property_read_bool(pdev->dev.parent, "dlg,tsi-as-adc");
>  
>  	if (hwmon->tsi_as_adc) {
> -		hwmon->tsiref = devm_regulator_get(pdev->dev.parent, "tsiref");
> -		if (IS_ERR(hwmon->tsiref)) {
> -			err = PTR_ERR(hwmon->tsiref);
> -			dev_err(&pdev->dev, "failed to get tsiref: %d", err);
> +		err = devm_regulator_get_enable_get_voltage(pdev->dev.parent,
> +							    "tsiref");
> +		if (err < 0)
>  			return err;
> -		}
> -
> -		err = regulator_enable(hwmon->tsiref);
> -		if (err)
> -			return err;
> -
> -		hwmon->tsiref_mv = regulator_get_voltage(hwmon->tsiref);
> -		if (hwmon->tsiref_mv < 0) {
> -			err = hwmon->tsiref_mv;
> -			goto exit_regulator;
> -		}
>  
>  		/* convert from microvolt (DT) to millivolt (hwmon) */
> -		hwmon->tsiref_mv /= 1000;
> +		hwmon->tsiref_mv = err / 1000;
>

Using a variable called err for a good value is a bit ugly but fair enough if that
is precedence in this driver.

>  }
> @@ -483,10 +466,8 @@ static void da9052_hwmon_remove(struct platform_device *pdev)
>  {
>  	struct da9052_hwmon *hwmon = platform_get_drvdata(pdev);
>  
> -	if (hwmon->tsi_as_adc) {
> +	if (hwmon->tsi_as_adc)
>  		da9052_free_irq(hwmon->da9052, DA9052_IRQ_TSIREADY, hwmon);
Superficially looks like devm_da9052_request_irq could be added that
uses devm_request_threaded_irq() to allow dropping this remaining handling.

Thanks,

Jonathan

> -		regulator_disable(hwmon->tsiref);
> -	}
>  }
>  
>  static struct platform_driver da9052_hwmon_driver = {
> 