linux-kernel - Re: [PATCH v3 1/2] iio: vadc: Qualcomm SPMI PMIC voltage ADC driver

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 for Android: free password hash cracker in your pocket

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

Date:	Thu, 02 Oct 2014 12:29:53 +0300
From:	"Ivan T. Ivanov" <iivanov@...sol.com>
To:	linux-kernel@...r.kernel.org
Cc:	linux-arm-msm@...r.kernel.org, linux-kernel@...r.kernel.org,
	devicetree@...r.kernel.org
Subject: Re: [PATCH v3 1/2] iio: vadc: Qualcomm SPMI PMIC voltage ADC driver


Hi Stan,

On 09/24/2014 03:56 PM, Stanimir Varbanov wrote:

<snip>

> +static int vadc_get_dt_data(struct vadc_priv *vadc, struct device_node *node)
> +{
> +	struct iio_chan_spec *iio_chan = vadc->iio_chans;
> +	const struct vadc_channels *vadc_chan;
> +	struct vadc_channel_prop prop;
> +	struct device_node *child;
> +	int ret, index = 0;
> +
> +	for_each_available_child_of_node(node, child) {
> +		ret = vadc_get_dt_channel_data(vadc->dev, &prop, child);
> +		if (ret)
> +			return ret;
> +
> +		vadc->chan_props[index] = prop;
> +
> +		vadc_chan = &vadc_chans[prop.channel];
> +
> +		iio_chan->channel = prop.channel;
> +		iio_chan->datasheet_name = vadc_chan->datasheet_name;
> +		iio_chan->info_mask_separate = vadc_chan->info_mask;
> +		iio_chan->type = vadc_chan->type;
> +		iio_chan->indexed = 1;
> +		iio_chan->scan_type.sign = 's';
> +		iio_chan->scan_type.realbits = 15;
> +		iio_chan->scan_type.storagebits = 16;
> +		iio_chan->address = index++;
> +
> +		iio_chan++;
> +	}
> +
> +	return 0;
> +}
> +

<snip>

> +static int vadc_probe(struct platform_device *pdev)
> +{

<snip>

> +
> +	indio_dev->dev.parent = dev;
> +	indio_dev->dev.of_node = node;
> +	indio_dev->name = pdev->name;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->info = &vadc_info;
> +	indio_dev->channels = vadc->iio_chans;
> +	indio_dev->num_channels = vadc->nchannels;

This will not work as we thought. Registration will be fine and entries
in sysfs are created as expected, but this is breaking numbering scheme
for client drivers. For us the problem is that iio framework expect channels
numbering to be linear and channel number should not be greater than
channel count. For example even if die temperature channel is always 8, if
I describe only 5 channels in DTS files (4 for reference points measurement)
and 1 for die temperature, clients could not get OF reference to 
temperature
channel using io-channels = <&pm8941_vadc 8>;

Jonathan, please, could you advise us.

Regards,
Ivan

> +
> +	return devm_iio_device_register(dev, indio_dev);
> +}
> +
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/