From: David Lechner Date: Sat, 28 Feb 2026 20:02:22 +0000 (-0600) Subject: iio: add IIO_DECLARE_QUATERNION() macro X-Git-Tag: v7.0-rc7~8^2~25^2~7 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=56bd57e7b161f75535df91b229b0b2c64c6e5581;p=thirdparty%2Flinux.git iio: add IIO_DECLARE_QUATERNION() macro Add a new IIO_DECLARE_QUATERNION() macro that is used to declare the field in an IIO buffer struct that contains a quaternion vector. Quaternions are currently the only IIO data type that uses the .repeat feature of struct iio_scan_type. This has an implicit rule that the element in the buffer must be aligned to the entire size of the repeated element. This macro will make that requirement explicit. Since this is the only user, we just call the macro IIO_DECLARE_QUATERNION() instead of something more generic. Signed-off-by: David Lechner Reviewed-by: Andy Shevchenko Cc: Signed-off-by: Jonathan Cameron --- diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index a9ecff191bd9..2c91b7659ce9 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -931,6 +931,18 @@ static inline void *iio_device_get_drvdata(const struct iio_dev *indio_dev) #define IIO_DECLARE_DMA_BUFFER_WITH_TS(type, name, count) \ __IIO_DECLARE_BUFFER_WITH_TS(type, name, count) __aligned(IIO_DMA_MINALIGN) +/** + * IIO_DECLARE_QUATERNION() - Declare a quaternion element + * @type: element type of the individual vectors + * @name: identifier name + * + * Quaternions are a vector composed of 4 elements (W, X, Y, Z). Use this macro + * to declare a quaternion element in a struct to ensure proper alignment in + * an IIO buffer. + */ +#define IIO_DECLARE_QUATERNION(type, name) \ + type name[4] __aligned(sizeof(type) * 4) + struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv); /* The information at the returned address is guaranteed to be cacheline aligned */