From: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
The Remote Request Substitution bit is a dominant bit ("0") in the CAN
XL frame. As some CAN XL controllers support to access this bit a new
CANXL_RRS value has been defined for the canxl_frame.flags element.
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Link: https://patch.msgid.link/20250124142347.7444-1-socketcan@xxxxxxxxxxxx
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
---
include/uapi/linux/can.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/can.h b/include/uapi/linux/can.h
index e78cbd85ce7c..42abf0679fb4 100644
--- a/include/uapi/linux/can.h
+++ b/include/uapi/linux/can.h
@@ -182,7 +182,7 @@ struct canfd_frame {
/*
* defined bits for canxl_frame.flags
*
- * The canxl_frame.flags element contains two bits CANXL_XLF and CANXL_SEC
+ * The canxl_frame.flags element contains three bits CANXL_[XLF|SEC|RRS]
* and shares the relative position of the struct can[fd]_frame.len element.
* The CANXL_XLF bit ALWAYS needs to be set to indicate a valid CAN XL frame.
* As a side effect setting this bit intentionally breaks the length checks
@@ -192,6 +192,7 @@ struct canfd_frame {
*/
#define CANXL_XLF 0x80 /* mandatory CAN XL frame flag (must always be set!) */
#define CANXL_SEC 0x01 /* Simple Extended Content (security/segmentation) */
+#define CANXL_RRS 0x02 /* Remote Request Substitution */
/* the 8-bit VCID is optionally placed in the canxl_frame.prio element */
#define CANXL_VCID_OFFSET 16 /* bit offset of VCID in prio element */
--
2.47.2
