Add new macros V4L2_FOURCC_CONV and V4L2_FOURCC_ARGS for use
in code that prints a fourcc. These macros can be used in both
kernel and userspace.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Suggested-by: Sakari Ailus <sakari.ailus@xxxxxx>
---
include/uapi/linux/videodev2.h | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
index 530638dffd93..7a34eb93437e 100644
--- a/include/uapi/linux/videodev2.h
+++ b/include/uapi/linux/videodev2.h
@@ -82,6 +82,19 @@
((__u32)(a) | ((__u32)(b) << 8) | ((__u32)(c) << 16) | ((__u32)(d) << 24))
#define v4l2_fourcc_be(a, b, c, d) (v4l2_fourcc(a, b, c, d) | (1U << 31))
+/*
+ * Helper macros to print a fourcc in a standard format. E.g.:
+ *
+ * printf("fourcc is " V4L2_FOURCC_CONV "\n", V4L2_FOURCC_ARGS(fourcc));
+ *
+ * Note that V4L2_FOURCC_ARGS reuses fourcc, so this can't be an
+ * expression with side-effects.
+ */
+#define V4L2_FOURCC_CONV "%c%c%c%c%s"
+#define V4L2_FOURCC_ARGS(fourcc) \
+ (fourcc) & 0x7f, ((fourcc) >> 8) & 0x7f, ((fourcc) >> 16) & 0x7f, \
+ ((fourcc) >> 24) & 0x7f, ((fourcc) & (1U << 31) ? "-BE" : "")
+
/*
* E N U M S
*/
--
2.20.1
