2014-10-02 09:55:07

by Ivan T. Ivanov

[permalink] [raw]
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);
> +}
> +
>


2014-10-02 12:08:07

by Ivan T. Ivanov

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] iio: vadc: Qualcomm SPMI PMIC voltage ADC driver

+iio maintainers

On Thu, 2014-10-02 at 12:29 +0300, Ivan T. Ivanov wrote:
> 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-arm-msm" in
> the body of a message to [email protected]
> More majordomo info at http://vger.kernel.org/majordomo-info.html

2014-10-04 11:51:33

by Jonathan Cameron

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] iio: vadc: Qualcomm SPMI PMIC voltage ADC driver

On 02/10/14 13:08, Ivan T. Ivanov wrote:
> +iio maintainers
>
> On Thu, 2014-10-02 at 12:29 +0300, Ivan T. Ivanov wrote:
>> 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.
I'd like to let the solution you proposed sit on the list a little longer.
It seems fairly sensible, but lets see what others suggest.

Jonathan
>>
>> Regards,
>> Ivan
>>
>>> +
>>> + return devm_iio_device_register(dev, indio_dev);
>>> +}
>>> +
>>>
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in
>> the body of a message to [email protected]
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
>

2014-10-07 11:57:25

by Ivan T. Ivanov

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] iio: vadc: Qualcomm SPMI PMIC voltage ADC driver

On Sat, 2014-10-04 at 12:51 +0100, Jonathan Cameron wrote:
> On 02/10/14 13:08, Ivan T. Ivanov wrote:
> > +iio maintainers
> >
> > On Thu, 2014-10-02 at 12:29 +0300, Ivan T. Ivanov wrote:
> >> 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.
> I'd like to let the solution you proposed sit on the list a little longer.
> It seems fairly sensible, but lets see what others suggest.

Sure.

Thank you.
Ivan

2014-10-16 13:58:49

by Ivan T. Ivanov

[permalink] [raw]
Subject: Re: [PATCH v3 1/2] iio: vadc: Qualcomm SPMI PMIC voltage ADC driver


Hi,

On Sat, 2014-10-04 at 12:51 +0100, Jonathan Cameron wrote:
> On 02/10/14 13:08, Ivan T. Ivanov wrote:
> > +iio maintainers
> >
> > On Thu, 2014-10-02 at 12:29 +0300, Ivan T. Ivanov wrote:
> > > 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.
> I'd like to let the solution you proposed sit on the list a little
> longer.
> It seems fairly sensible, but lets see what others suggest.

It is quiet :-) Just for the record the same aproach is used in
PWM, Reset, Gpio and PHY frameworks.

Patch in question: https://lkml.org/lkml/2014/10/2/199

Regards,
Ivan


>
> Jonathan