Received-SPF: softfail (google.com: domain of transitioning linux-kernel-owner@vger.kernel.org does not designate 23.128.96.19 as permitted sender) client-ip=23.128.96.19;
Mime-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain; charset=UTF-8
Date:   Wed, 08 Jun 2022 12:18:52 +0200
Message-Id: <CKKOCWP2NYO5.GH08U776B1KU@otso>
Cc:     <~postmarketos/upstreaming@lists.sr.ht>,
        <phone-devel@vger.kernel.org>,
        "Konrad Dybcio" <konrad.dybcio@somainline.org>,
        "Marijn Suijten" <marijn.suijten@somainline.org>,
        "AngeloGioacchino Del Regno" 
        <angelogioacchino.delregno@somainline.org>,
        "Song Qiang" <songqiang1304521@gmail.com>,
        "Lars-Peter Clausen" <lars@metafoo.de>,
        "Rob Herring" <robh+dt@kernel.org>,
        "Krzysztof Kozlowski" <krzysztof.kozlowski+dt@linaro.org>,
        "Andy Gross" <agross@kernel.org>,
        "Bjorn Andersson" <bjorn.andersson@linaro.org>,
        "Liam Girdwood" <lgirdwood@gmail.com>,
        "Mark Brown" <broonie@kernel.org>, <linux-iio@vger.kernel.org>,
        <devicetree@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>
Subject: Re: [PATCH 3/5] proximity: vl53l0x: Handle the VDD regulator
From:   "Luca Weiss" <luca.weiss@fairphone.com>
To:     "Markuss Broks" <markuss.broks@gmail.com>,
        <linux-kernel@vger.kernel.org>, <jic23@kernel.org>
References: <20220523175344.5845-1-markuss.broks@gmail.com>
 <20220523175344.5845-4-markuss.broks@gmail.com>
In-Reply-To: <20220523175344.5845-4-markuss.broks@gmail.com>
Precedence: bulk

Hi Markuss,

On Mon May 23, 2022 at 7:53 PM CEST, Markuss Broks wrote:
> Handle the regulator supplying the VDD pin of VL53L0X.
>
> Signed-off-by: Markuss Broks <markuss.broks@gmail.com>
> ---
>  drivers/iio/proximity/vl53l0x-i2c.c | 37 +++++++++++++++++++++++++++++
>  1 file changed, 37 insertions(+)
>
> diff --git a/drivers/iio/proximity/vl53l0x-i2c.c b/drivers/iio/proximity/=
vl53l0x-i2c.c
> index 12a3e2eff464..8581a873919f 100644
> --- a/drivers/iio/proximity/vl53l0x-i2c.c
> +++ b/drivers/iio/proximity/vl53l0x-i2c.c
> @@ -43,6 +43,7 @@
>  struct vl53l0x_data {
>  	struct i2c_client *client;
>  	struct completion completion;
> +	struct regulator *vdd_supply;
>  };
> =20
>  static irqreturn_t vl53l0x_handle_irq(int irq, void *priv)
> @@ -192,10 +193,31 @@ static const struct iio_info vl53l0x_info =3D {
>  	.read_raw =3D vl53l0x_read_raw,
>  };
> =20
> +static void vl53l0x_power_off(void *_data)
> +{
> +	struct vl53l0x_data *data =3D _data;
> +
> +	regulator_disable(data->vdd_supply);
> +}
> +
> +static int vl53l0x_power_on(struct vl53l0x_data *data)
> +{
> +	int ret;
> +
> +	ret =3D regulator_enable(data->vdd_supply);
> +	if (ret)
> +		return ret;
> +
> +	usleep_range(3200, 5000);
> +
> +	return 0;
> +}
> +
>  static int vl53l0x_probe(struct i2c_client *client)
>  {
>  	struct vl53l0x_data *data;
>  	struct iio_dev *indio_dev;
> +	int error;
> =20
>  	indio_dev =3D devm_iio_device_alloc(&client->dev, sizeof(*data));
>  	if (!indio_dev)
> @@ -210,6 +232,21 @@ static int vl53l0x_probe(struct i2c_client *client)
>  				     I2C_FUNC_SMBUS_BYTE_DATA))
>  		return -EOPNOTSUPP;
> =20
> +	data->vdd_supply =3D devm_regulator_get_optional(&client->dev, "vdd");
> +	if (IS_ERR(data->vdd_supply))
> +		return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply),
> +				     "Unable to get VDD regulator\n");

It looks like this optional regulator is not actually optional.

[    1.919995] vl53l0x-i2c 1-0029: error -ENODEV: Unable to get VDD regulat=
or

When using devm_regulator_get instead, a dummy regulator gets returned
which I think is what we want here:

[    1.905518] vl53l0x-i2c 1-0029: supply vdd not found, using dummy regula=
tor

Can you fix this up or should I send a patch?

Regards
Luca


> +
> +	error =3D vl53l0x_power_on(data);
> +	if (error)
> +		return dev_err_probe(&client->dev, error,
> +				     "Failed to power on the chip\n");
> +
> +	error =3D devm_add_action_or_reset(&client->dev, vl53l0x_power_off, dat=
a);
> +	if (error)
> +		return dev_err_probe(&client->dev, error,
> +				     "Failed to install poweroff action\n");
> +
>  	indio_dev->name =3D "vl53l0x";
>  	indio_dev->info =3D &vl53l0x_info;
>  	indio_dev->channels =3D vl53l0x_channels;
> --=20
> 2.36.1