Re: [PATCH] iio: core: Return error for failed read_reg

[Jonathan Cameron <jic23@kernel.org>]

On Tue, 5 Sep 2017 17:20:57 +0200
Lars-Peter Clausen <lars@metafoo.de> wrote:

> On 09/05/2017 04:34 PM, Lars-Peter Clausen wrote:
> > From: Matt Fornero <matt.fornero@mathworks.com>
> > 
> > If an IIO device returns an error code for a read access via debugfs, it
> > is currently ignored by the IIO core (other than emitting an error
> > message). Instead, return this error code to user space, so upper layers
> > can detect it correctly.
> > 
> > Signed-off-by: Matt Fornero <matt.fornero@mathworks.com>  
> 
> Sorry, this should also have had:
> 
> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
> 
Applied to the fixes-togreg branch of iio.git and marked for stable.

Thanks,

Jonathan

> > ---
> >  drivers/iio/industrialio-core.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> > index 7a5aa127c52e..9c4cfd19b739 100644
> > --- a/drivers/iio/industrialio-core.c
> > +++ b/drivers/iio/industrialio-core.c
> > @@ -310,8 +310,10 @@ static ssize_t iio_debugfs_read_reg(struct file *file, char __user *userbuf,
> >  	ret = indio_dev->info->debugfs_reg_access(indio_dev,
> >  						  indio_dev->cached_reg_addr,
> >  						  0, &val);
> > -	if (ret)
> > +	if (ret) {
> >  		dev_err(indio_dev->dev.parent, "%s: read failed\n", __func__);
> > +		return ret;
> > +	}
> >  
> >  	len = snprintf(buf, sizeof(buf), "0x%X\n", val);
> >  
> >   
>