iio: inkern: add error case in iio_channel_get()

The datasheet name is defined in the IIO driver.
 On the other hand, the adc_channel_label is configured in
 the platform side.
 If the datasheet name is not matched with any adc_channel_label,
 the iio_channel_get() should be returned as error for preventing
 invalid channel data access.

 This can be handled either way.
 (a) checking null data when using it : in the xxx_read_raw()
 or
 (b) error returns when the channel is requested : this patch

 The IIO consumer can't use the channel with invalid channel spec.
 Therefore case (b) is more reasonable.

Signed-off-by: Milo(Woogyom) Kim <milo.kim@ti.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
Kim, Milo 2012-09-17 09:44:00 +01:00 committed by Jonathan Cameron
parent 2cc412b513
commit b2b79ffa40

View file

@ -136,12 +136,21 @@ struct iio_channel *iio_channel_get(const char *name, const char *channel_name)
channel->indio_dev = c->indio_dev;
if (c->map->adc_channel_label)
if (c->map->adc_channel_label) {
channel->channel =
iio_chan_spec_from_name(channel->indio_dev,
c->map->adc_channel_label);
if (channel->channel == NULL)
goto error_no_chan;
}
return channel;
error_no_chan:
iio_device_put(c->indio_dev);
kfree(channel);
return ERR_PTR(-EINVAL);
}
EXPORT_SYMBOL_GPL(iio_channel_get);