[v3,4/4] iplink_can: add new CAN FD bittiming parameters: Transmitter Delay Compensation (TDC)

diff --git a/include/uapi/linux/can/netlink.h b/include/uapi/linux/can/netlink.h
index 00c763df..d5cc2761 100644
--- a/include/uapi/linux/can/netlink.h
+++ b/include/uapi/linux/can/netlink.h
@@ -134,12 +134,31 @@  enum {
 	IFLA_CAN_BITRATE_CONST,
 	IFLA_CAN_DATA_BITRATE_CONST,
 	IFLA_CAN_BITRATE_MAX,
-	__IFLA_CAN_MAX
-};
+	IFLA_CAN_TDC,
 
-#define IFLA_CAN_MAX	(__IFLA_CAN_MAX - 1)
+	/* add new constants above here */
+	__IFLA_CAN_MAX,
+	IFLA_CAN_MAX = __IFLA_CAN_MAX - 1
+};
 
 /* u16 termination range: 1..65535 Ohms */
 #define CAN_TERMINATION_DISABLED 0
 
+/*
+ * CAN FD Transmitter Delay Compensation (TDC)
+ */
+enum {
+	IFLA_CAN_TDC_UNSPEC,
+	IFLA_CAN_TDC_TDCV_MAX,	/* u32 */
+	IFLA_CAN_TDC_TDCO_MAX,	/* u32 */
+	IFLA_CAN_TDC_TDCF_MAX,	/* u32 */
+	IFLA_CAN_TDC_TDCV,	/* u32 */
+	IFLA_CAN_TDC_TDCO,	/* u32 */
+	IFLA_CAN_TDC_TDCF,	/* u32 */
+
+	/* add new constants above here */
+	__IFLA_CAN_TDC,
+	IFLA_CAN_TDC_MAX = __IFLA_CAN_TDC - 1
+};
+
 #endif /* !_UAPI_CAN_NETLINK_H */
diff --git a/ip/iplink_can.c b/ip/iplink_can.c
index 311c097d..ea049999 100644
--- a/ip/iplink_can.c
+++ b/ip/iplink_can.c
@@ -28,6 +28,7 @@  static void print_usage(FILE *f)
 		"\n"
 		"\t[ dbitrate BITRATE [ dsample-point SAMPLE-POINT] ] |\n"
 		"\t[ dtq TQ dprop-seg PROP_SEG dphase-seg1 PHASE-SEG1\n \t  dphase-seg2 PHASE-SEG2 [ dsjw SJW ] ]\n"
+		"\t[ tdcv TDCV tdco TDCO tdcf TDCF ]\n"
 		"\n"
 		"\t[ loopback { on | off } ]\n"
 		"\t[ listen-only { on | off } ]\n"
@@ -51,6 +52,9 @@  static void print_usage(FILE *f)
 		"\t	  PHASE-SEG1	:= { NUMBER }\n"
 		"\t	  PHASE-SEG2	:= { NUMBER }\n"
 		"\t	  SJW		:= { NUMBER }\n"
+		"\t	  TDCV		:= { 0 | NUMBER }\n"
+		"\t	  TDCO		:= { 0 | NUMBER }\n"
+		"\t	  TDCF		:= { NUMBER }\n"
 		"\t	  RESTART-MS	:= { 0 | NUMBER }\n"
 		);
 }
@@ -116,6 +120,8 @@  static int can_parse_opt(struct link_util *lu, int argc, char **argv,
 {
 	struct can_bittiming bt = {}, dbt = {};
 	struct can_ctrlmode cm = {0, 0};
+	struct rtattr *tdc;
+	__u32 tdcv = -1, tdco = -1, tdcf = -1;
 
 	while (argc > 0) {
 		if (matches(*argv, "bitrate") == 0) {
@@ -181,6 +187,18 @@  static int can_parse_opt(struct link_util *lu, int argc, char **argv,
 			NEXT_ARG();
 			if (get_u32(&dbt.sjw, *argv, 0))
 				invarg("invalid \"dsjw\" value\n", *argv);
+		} else if (matches(*argv, "tdcv") == 0) {
+			NEXT_ARG();
+			if (get_u32(&tdcv, *argv, 0))
+				invarg("invalid \"tdcv\" value\n", *argv);
+		} else if (matches(*argv, "tdco") == 0) {
+			NEXT_ARG();
+			if (get_u32(&tdco, *argv, 0))
+				invarg("invalid \"tdco\" value\n", *argv);
+		} else if (matches(*argv, "tdcf") == 0) {
+			NEXT_ARG();
+			if (get_u32(&tdcf, *argv, 0))
+				invarg("invalid \"tdcf\" value\n", *argv);
 		} else if (matches(*argv, "loopback") == 0) {
 			NEXT_ARG();
 			set_ctrlmode("loopback", *argv, &cm,
@@ -254,6 +272,17 @@  static int can_parse_opt(struct link_util *lu, int argc, char **argv,
 	if (cm.mask)
 		addattr_l(n, 1024, IFLA_CAN_CTRLMODE, &cm, sizeof(cm));
 
+	if (tdcv != -1 || tdco != -1 || tdcf != -1) {
+		tdc = addattr_nest(n, 1024, IFLA_CAN_TDC | NLA_F_NESTED);
+		if (tdcv != -1)
+			addattr32(n, 1024, IFLA_CAN_TDC_TDCV, tdcv);
+		if (tdco != -1)
+			addattr32(n, 1024, IFLA_CAN_TDC_TDCO, tdco);
+		if (tdcf != -1)
+			addattr32(n, 1024, IFLA_CAN_TDC_TDCF, tdcf);
+		addattr_nest_end(n, tdc);
+	}
+
 	return 0;
 }
 
@@ -294,6 +323,46 @@  static void can_print_data_timing_min_max(const char *attr, int min, int max)
 	can_print_timing_min_max(attr, min, max);
 }
 
+static void can_print_tdc_opt(FILE *f, struct rtattr *tdc_attr)
+{
+	struct rtattr *tb[IFLA_CAN_TDC_MAX + 1];
+
+	parse_rtattr_nested(tb, IFLA_CAN_TDC_MAX, tdc_attr);
+	if (tb[IFLA_CAN_TDC_TDCV] && tb[IFLA_CAN_TDC_TDCO] &&
+	    tb[IFLA_CAN_TDC_TDCF]) {
+		__u32 *tdcv = RTA_DATA(tb[IFLA_CAN_TDC_TDCV]);
+		__u32 *tdco = RTA_DATA(tb[IFLA_CAN_TDC_TDCO]);
+		__u32 *tdcf = RTA_DATA(tb[IFLA_CAN_TDC_TDCF]);
+
+		open_json_object("tdc");
+		can_print_nl_indent();
+		print_uint(PRINT_ANY, "tdcv", " tdcv %u", *tdcv);
+		print_uint(PRINT_ANY, "tdco", " tdco %u", *tdco);
+		print_uint(PRINT_ANY, "tdcf", " tdcf %u", *tdcf);
+		close_json_object();
+	}
+}
+
+static void can_print_tdc_const_opt(FILE *f, struct rtattr *tdc_attr)
+{
+	struct rtattr *tb[IFLA_CAN_TDC_MAX + 1];
+
+	parse_rtattr_nested(tb, IFLA_CAN_TDC_MAX, tdc_attr);
+	if (tb[IFLA_CAN_TDC_TDCV_MAX] && tb[IFLA_CAN_TDC_TDCO_MAX] &&
+	    tb[IFLA_CAN_TDC_TDCF_MAX]) {
+		__u32 *tdcv_max = RTA_DATA(tb[IFLA_CAN_TDC_TDCV_MAX]);
+		__u32 *tdco_max = RTA_DATA(tb[IFLA_CAN_TDC_TDCO_MAX]);
+		__u32 *tdcf_max = RTA_DATA(tb[IFLA_CAN_TDC_TDCF_MAX]);
+
+		open_json_object("tdc");
+		can_print_nl_indent();
+		print_uint(PRINT_ANY, "tdcv_max", " tdcv_max %u", *tdcv_max);
+		print_uint(PRINT_ANY, "tdco_max", " tdco_max %u", *tdco_max);
+		print_uint(PRINT_ANY, "tdcf_max", " tdcf_max %u", *tdcf_max);
+		close_json_object();
+	}
+}
+
 static void can_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 {
 	if (!tb)
@@ -425,6 +494,10 @@  static void can_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 			   dbt->phase_seg2);
 		print_uint(PRINT_ANY, "sjw", " dsjw %u", dbt->sjw);
 		print_uint(PRINT_ANY, "brp", " dbrp %u", dbt->brp);
+
+		if (tb[IFLA_CAN_TDC])
+			can_print_tdc_opt(f, tb[IFLA_CAN_TDC]);
+
 		close_json_object();
 	}
 
@@ -445,6 +518,10 @@  static void can_print_opt(struct link_util *lu, FILE *f, struct rtattr *tb[])
 		can_print_data_timing_min_max("brp",
 					      dbtc->brp_min, dbtc->brp_max);
 		print_uint(PRINT_ANY, "brp_inc", " brp_inc %u", dbtc->brp_inc);
+
+		if (tb[IFLA_CAN_TDC])
+			can_print_tdc_const_opt(f, tb[IFLA_CAN_TDC]);
+
 		close_json_object();
 	}