Re: [Outreachy kernel] [IIO] Help understanding iio_priv(..)

[Aishwarya Pant <aishpant@gmail.com>]

On Tue, Mar 14, 2017 at 01:43:08PM +0100, Julia Lawall wrote:
> 
> 
> On Tue, 14 Mar 2017, Aishwarya Pant wrote:
> 
> > Hi
> >
> > I have been looking at the IIO task and came across this function
> > iio_priv(..). It is defined as-
> >
> >
> > static inline void *iio_priv(const struct iio_dev *indio_dev)
> > {
> >         return (char *)indio_dev + ALIGN(sizeof(struct iio_dev),
> > 	IIO_ALIGN);
> > }
> >
> > It returns a void pointer and used as struct dev_state = iio_priv(indio_dev).
> > Looks like it is used to store an iio device state private to the file.
> >
> > Could someone help me understand what exactly is happening inside here?
> 
> Probably it would help to look at how the priv pointer is initialized.

Looking at how iio_dev is defined helped :)

struct iio_dev indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip))

> 
> julia
> 
> >
> > Thanks
> > Aishwarya
> >
> >
> >
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