linux-kernel - Re: [PATCH v2 3/4] iio: vcnl4000: Export near level property for proximity sensor

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <c787921f-c412-4986-14ea-e31b531d3d5b@metafoo.de>
Date:   Mon, 16 Mar 2020 19:23:01 +0100
From:   Lars-Peter Clausen <lars@...afoo.de>
To:     Guido Günther <agx@...xcpu.org>,
        Tomas Novotny <tomas@...otny.cz>,
        Jonathan Cameron <jic23@...nel.org>,
        Hartmut Knaack <knaack.h@....de>,
        Peter Meerwald-Stadler <pmeerw@...erw.net>,
        "Angus Ainslie (Purism)" <angus@...ea.ca>,
        Marco Felsch <m.felsch@...gutronix.de>,
        Thomas Gleixner <tglx@...utronix.de>,
        linux-iio@...r.kernel.org, linux-kernel@...r.kernel.org,
        devicetree@...r.kernel.org
Subject: Re: [PATCH v2 3/4] iio: vcnl4000: Export near level property for
 proximity sensor

On 3/16/20 6:46 PM, Guido Günther wrote:
> [...]
> +static ssize_t vcnl4000_read_near_level(struct iio_dev *indio_dev,
> +					uintptr_t priv,
> +					const struct iio_chan_spec *chan,
> +					char *buf)
> +{
> +	struct vcnl4000_data *data = iio_priv(indio_dev);
> +
> +	return sprintf(buf, "%u\n", data->near_level);
> +}
> +
> +static const struct iio_chan_spec_ext_info vcnl4000_ext_info[] = {
> +	{
> +		.name = "near_level",

Generally having properties with a underscore in them breaks generic 
parsing of the property name by userspace applications. This is because 
we use underscores to separate different components (type, modifier, 
etc.) of the attribute from each other.

Do you think calling this "nearlevel" would work?

I know there are existing bad examples of properties that use an 
underscore, but we should try to limit introducing new ones.

> +		.shared = IIO_SEPARATE,
> +		.read = vcnl4000_read_near_level,
> +	},
> +	{ /* sentinel */ }
> +};
> +
>   static const struct iio_chan_spec vcnl4000_channels[] = {
>   	{
>   		.type = IIO_LIGHT,
> @@ -350,6 +371,7 @@ static const struct iio_chan_spec vcnl4000_channels[] = {
>   	}, {
>   		.type = IIO_PROXIMITY,
>   		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.ext_info = vcnl4000_ext_info,
>   	}
>   };
>   
> @@ -439,6 +461,10 @@ static int vcnl4000_probe(struct i2c_client *client,
>   	dev_dbg(&client->dev, "%s Ambient light/proximity sensor, Rev: %02x\n",
>   		data->chip_spec->prod, data->rev);
>   
> +	if (device_property_read_u32(&client->dev, "near-level",
> +				     &data->near_level) < 0)
> +		data->near_level = 0;
> +
>   	indio_dev->dev.parent = &client->dev;
>   	indio_dev->info = &vcnl4000_info;
>   	indio_dev->channels = vcnl4000_channels;