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