On 10/15/2012 10:35 AM, Lars-Peter Clausen wrote: > Some datasheets use a different unit to specify the channel scale than what IIO > expects it to be. This patch adds two helper macros which allow to convert units > commonly used in datasheets to IIO units: > > * acceleration: g -> meter / second**2 > * angular velocity: degree (/ second) -> rad (/ second) > > This makes it much more convenient to specify and also easier to verify a > channel's scale attribute. > > Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx> Good idea applied to togreg branch of iio.git (or at least will be when I get home from travelling). > --- > include/linux/iio/iio.h | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h > index c0ae76a..7806c24 100644 > --- a/include/linux/iio/iio.h > +++ b/include/linux/iio/iio.h > @@ -618,4 +618,20 @@ static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev) > }; > #endif > > +/** > + * IIO_DEGREE_TO_RAD() - Convert degree to rad > + * @deg: A value in degree > + * > + * Returns the given value converted from degree to rad > + */ > +#define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL) > + > +/** > + * IIO_G_TO_M_S_2() - Convert g to meter / second**2 > + * @g: A value in g > + * > + * Returns the given value converted from g to meter / second**2 > + */ > +#define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL) > + > #endif /* _INDUSTRIAL_IO_H_ */ > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
