diff options
| author | Lars-Peter Clausen <lars@metafoo.de> | 2012-07-09 11:00:00 +0200 |
|---|---|---|
| committer | Jonathan Cameron <jic23@kernel.org> | 2012-07-09 19:18:15 +0200 |
| commit | 939546d1a9f47ed169554c711e1e05965b84ffe1 (patch) | |
| tree | 80ee898547145c1b202a77d3ca5f642809ba9778 /include | |
| parent | staging:iio:adt7410: use local platformdata if none is specified (diff) | |
| download | linux-939546d1a9f47ed169554c711e1e05965b84ffe1.tar.xz linux-939546d1a9f47ed169554c711e1e05965b84ffe1.zip | |
iio: Add callback to check whether a scan mask is valid
This is useful for cases where the number of valid scan masks grows
exponentially, but it is rather easy to check whether a mask is valid or not
programmatically.
An example of such a case is a device with multiple ADCs where each ADC has a
upstream MUX, which allows to select from a number of physical channels.
+-------+ +-------+
| | | | --- Channel 1
| ADC 1 |---| MUX 1 | --- ...
| | | | --- Channel M
+-------+ +-------+
. . .
. . .
. . .
+-------+ +-------+
| | | | --- Channel M * N + 1
| ADC N |---| MUX N | --- ...
| | | | --- Channel M * N + M
+-------+ +-------+
The number of necessary scan masks for this case is (M+1)**N - 1, on the other
hand it is easy to check whether subsets for each ADC of the scanmask have only
one bit set.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/iio/iio.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index 2afbb6f01afc..be82936c4089 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -363,12 +363,16 @@ struct iio_info { * @predisable: [DRIVER] function to run prior to marking buffer * disabled * @postdisable: [DRIVER] function to run after marking buffer disabled + * @validate_scan_mask: [DRIVER] function callback to check whether a given + * scan mask is valid for the device. */ struct iio_buffer_setup_ops { int (*preenable)(struct iio_dev *); int (*postenable)(struct iio_dev *); int (*predisable)(struct iio_dev *); int (*postdisable)(struct iio_dev *); + bool (*validate_scan_mask)(struct iio_dev *indio_dev, + const unsigned long *scan_mask); }; /** |