Merge branch 'dpll-rework-fractional-frequency-offset-reporting'

Ivan Vecera says:

====================
dpll: rework fractional frequency offset reporting

Rework how the fractional frequency offset (FFO) is reported in
the DPLL subsystem.

Both fractional-frequency-offset (PPM) and
fractional-frequency-offset-ppt (PPT) attributes are now present at
the top level of a pin and inside each pin-parent-device nest. They
carry the same measurement at different precisions.

Introduce enum dpll_ffo_type and struct dpll_ffo_param to distinguish
FFO contexts: DPLL_FFO_PORT_RXTX_RATE for the RX vs TX symbol rate
offset at the top level, and DPLL_FFO_PIN_DEVICE for the pin vs
parent DPLL offset in the nest. Drivers declare which types they
support via the supported_ffo bitmask in dpll_pin_ops; the core only
calls ffo_get for opted-in types.

Patch 1 adds the type-safe FFO API, updates the YAML spec, netlink
handling, and documentation, and converts mlx5 and zl3073x drivers.

Patch 2 implements the nested FFO for zl3073x using the
dpll_df_offset_x register with ref_ofst=1, providing 2^-48
resolution. The old per-reference frequency measurement is removed
as it was redundant with measured-frequency.
====================

Link: https://patch.msgid.link/20260511155816.99936-1-ivecera@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 15 insertions, 1 deletions

diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index 193abfb6ce66..82dfadd9f593 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -60,7 +60,20 @@ struct dpll_device_ops {
 				struct netlink_ext_ack *extack);
 };
 
+enum dpll_ffo_type {
+	DPLL_FFO_PORT_RXTX_RATE,
+	DPLL_FFO_PIN_DEVICE,
+
+	__DPLL_FFO_TYPE_MAX,
+};
+
+struct dpll_ffo_param {
+	enum dpll_ffo_type type;
+	s64 ffo;
+};
+
 struct dpll_pin_ops {
+	unsigned long supported_ffo;
 	int (*frequency_set)(const struct dpll_pin *pin, void *pin_priv,
 			     const struct dpll_device *dpll, void *dpll_priv,
 			     const u64 frequency,
@@ -121,7 +134,8 @@ struct dpll_pin_ops {
 				struct netlink_ext_ack *extack);
 	int (*ffo_get)(const struct dpll_pin *pin, void *pin_priv,
 		       const struct dpll_device *dpll, void *dpll_priv,
-		       s64 *ffo, struct netlink_ext_ack *extack);
+		       struct dpll_ffo_param *ffo,
+		       struct netlink_ext_ack *extack);
 	int (*measured_freq_get)(const struct dpll_pin *pin, void *pin_priv,
 				 const struct dpll_device *dpll,
 				 void *dpll_priv, u64 *measured_freq,