[PATCH iproute2-next 2/2] dpll: add fractional-frequency-offset to parent-device

[Ivan Vecera <ivecera@redhat.com>]

Kernel commit 9c11fcb2e9a54 ("dpll: add fractional frequency offset
to pin-parent-device") added fractional-frequency-offset (PPM) and
fractional-frequency-offset-ppt (PPT) attributes to the
pin-parent-device nested attribute set, alongside the existing
top-level pin attributes. Add their display into
dpll_pin_print_parent_devices() and add ppm and ppt units to the
respective outputs.

Extract dpll_pr_ffo() helper to consolidate the duplicated PPM/PPT
fallback logic used in both top-level and parent-device contexts.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 dpll/dpll.c     | 27 ++++++++++++++++++++++-----
 man/man8/dpll.8 |  4 +++-
 2 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/dpll/dpll.c b/dpll/dpll.c
index bd9ab3c6033f..1077fc259725 100644
--- a/dpll/dpll.c
+++ b/dpll/dpll.c
@@ -514,6 +514,26 @@ static void dpll_pr_phase_offset(struct nlattr *attr)
 	print_s64(PRINT_FP, NULL, "%03lld ps", d.rem);
 }
 
+static void dpll_pr_ffo(struct nlattr **tb, bool top_level)
+{
+	const char *fmt;
+
+	if (json || !tb[DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT]) {
+		if (top_level)
+			fmt = "  fractional-frequency-offset: %" PRId64 " ppm\n";
+		else
+			fmt = " fractional-frequency-offset %" PRId64 " ppm";
+		DPLL_PR_SINT_FMT(tb, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET,
+				 "fractional-frequency-offset", fmt);
+	}
+	if (top_level)
+		fmt = "  fractional-frequency-offset: %" PRId64 " ppt\n";
+	else
+		fmt = " fractional-frequency-offset %" PRId64 " ppt";
+	DPLL_PR_SINT_FMT(tb, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT,
+			 "fractional-frequency-offset-ppt", fmt);
+}
+
 /* Measured frequency - JSON prints raw mHz value, FP prints fractional Hz */
 static void dpll_pr_measured_frequency(struct nlattr *attr)
 {
@@ -1602,6 +1622,7 @@ static void dpll_pin_print_parent_devices(struct nlattr *attr)
 				     "operstate", " operstate %s",
 				     dpll_pin_operstate_name);
 		dpll_pr_phase_offset(tb_parent[DPLL_A_PIN_PHASE_OFFSET]);
+		dpll_pr_ffo(tb_parent, false);
 
 		print_nl();
 		close_json_object();
@@ -1694,11 +1715,7 @@ static void dpll_pin_print_attrs(struct nlattr **tb)
 	DPLL_PR_INT_FMT(tb, DPLL_A_PIN_PHASE_ADJUST, "phase-adjust",
 			"  phase-adjust: %d ps\n");
 
-	if (json || !tb[DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT])
-		DPLL_PR_SINT(tb, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET,
-			     "fractional-frequency-offset");
-	DPLL_PR_SINT(tb, DPLL_A_PIN_FRACTIONAL_FREQUENCY_OFFSET_PPT,
-		     "fractional-frequency-offset-ppt");
+	dpll_pr_ffo(tb, true);
 
 	DPLL_PR_U64_FMT(tb, DPLL_A_PIN_ESYNC_FREQUENCY, "esync-frequency",
 			"  esync-frequency: %" PRIu64 " Hz\n");
diff --git a/man/man8/dpll.8 b/man/man8/dpll.8
index f4cbcfc005c1..f409ba6bb9c5 100644
--- a/man/man8/dpll.8
+++ b/man/man8/dpll.8
@@ -263,7 +263,9 @@ Capabilities (state-can-change, priority-can-change, direction-can-change)
 .IP \[bu]
 Phase adjustment range, granularity, and current value
 .IP \[bu]
-Parent device relationships (direction, priority, state, operstate, phase offset)
+Fractional frequency offset in ppm (RX vs TX symbol rate on media)
+.IP \[bu]
+Parent device relationships (direction, priority, state, operstate, phase offset, fractional frequency offset in ppt)
 .IP \[bu]
 Parent pin relationships
 .IP \[bu]
-- 
2.53.0