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.
To read/write the Remote Request Substitution (RRS) bit in the CAN XL
frame the CAN_CTRLMODE_XL_RRS has to be enabled in CAN driver.
Signed-off-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
---
include/uapi/linux/can.h | 5 ++++-
include/uapi/linux/can/netlink.h | 1 +
2 files changed, 5 insertions(+), 1 deletion(-)
diff --git a/include/uapi/linux/can.h b/include/uapi/linux/can.h
index e78cbd85ce7c..77d3a940beb0 100644
--- a/include/uapi/linux/can.h
+++ b/include/uapi/linux/can.h
@@ -180,20 +180,23 @@ 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
* for Classical CAN and CAN FD frames.
+ * To read/write the Remote Request Substitution (RRS) bit in the CAN XL
+ * frame the CAN_CTRLMODE_XL_RRS has to be enabled in CAN driver.
*
* Undefined bits in canxl_frame.flags are reserved and shall be set to zero.
*/
#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 */
#define CANXL_VCID_VAL_MASK 0xFFUL /* VCID is an 8-bit value */
#define CANXL_VCID_MASK (CANXL_VCID_VAL_MASK << CANXL_VCID_OFFSET)
diff --git a/include/uapi/linux/can/netlink.h b/include/uapi/linux/can/netlink.h
index f4fb8eea8f35..55b8374ab094 100644
--- a/include/uapi/linux/can/netlink.h
+++ b/include/uapi/linux/can/netlink.h
@@ -104,10 +104,11 @@ struct can_ctrlmode {
#define CAN_CTRLMODE_TDC_AUTO 0x200 /* FD transceiver automatically calculates TDCV */
#define CAN_CTRLMODE_TDC_MANUAL 0x400 /* FD TDCV is manually set up by user */
#define CAN_CTRLMODE_XL 0x800 /* CAN XL mode */
#define CAN_CTRLMODE_XL_TDC_AUTO 0x1000 /* XL transceiver automatically calculates TDCV */
#define CAN_CTRLMODE_XL_TDC_MANUAL 0x2000 /* XL TDCV is manually set up by user */
+#define CAN_CTRLMODE_XL_RRS 0x4000 /* XL enable RRS bit access */
/*
* CAN device statistics
*/
struct can_device_stats {
--
2.45.2
