dpll: add clock quality level attribute and op

In order to allow driver expose quality level of the clock it is
running, introduce a new netlink attr with enum to carry it to the
userspace. Also, introduce an op the dpll netlink code calls into the
driver to obtain the value.

Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Link: https://patch.msgid.link/20241030081157.966604-2-jiri@resnulli.us
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Documentation/netlink/specs/dpll.yaml

@@ -85,6 +85,36 @@ definitions:
           This may happen for example if dpll device was previously
           locked on an input pin of type PIN_TYPE_SYNCE_ETH_PORT.
     render-max: true
+  -
+    type: enum
+    name: clock-quality-level
+    doc: |
+      level of quality of a clock device. This mainly applies when
+      the dpll lock-status is DPLL_LOCK_STATUS_HOLDOVER.
+      The current list is defined according to the table 11-7 contained
+      in ITU-T G.8264/Y.1364 document. One may extend this list freely
+      by other ITU-T defined clock qualities, or different ones defined
+      by another standardization body (for those, please use
+      different prefix).
+    entries:
+      -
+        name: itu-opt1-prc
+        value: 1
+      -
+        name: itu-opt1-ssu-a
+      -
+        name: itu-opt1-ssu-b
+      -
+        name: itu-opt1-eec1
+      -
+        name: itu-opt1-prtc
+      -
+        name: itu-opt1-eprtc
+      -
+        name: itu-opt1-eeec
+      -
+        name: itu-opt1-eprc
+    render-max: true
   -
     type: const
     name: temp-divider
@@ -252,6 +282,17 @@ attribute-sets:
         name: lock-status-error
         type: u32
         enum: lock-status-error
+      -
+        name: clock-quality-level
+        type: u32
+        enum: clock-quality-level
+        multi-attr: true
+        doc: |
+          Level of quality of a clock device. This mainly applies when
+          the dpll lock-status is DPLL_LOCK_STATUS_HOLDOVER. This could
+          be put to message multiple times to indicate possible parallel
+          quality levels (e.g. one specified by ITU option 1 and another
+          one specified by option 2).
   -
     name: pin
     enum-name: dpll_a_pin

drivers/dpll/dpll_netlink.c

@@ -169,6 +169,27 @@ dpll_msg_add_temp(struct sk_buff *msg, struct dpll_device *dpll,
 	return 0;
 }
 
+static int
+dpll_msg_add_clock_quality_level(struct sk_buff *msg, struct dpll_device *dpll,
+				 struct netlink_ext_ack *extack)
+{
+	const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+	DECLARE_BITMAP(qls, DPLL_CLOCK_QUALITY_LEVEL_MAX) = { 0 };
+	enum dpll_clock_quality_level ql;
+	int ret;
+
+	if (!ops->clock_quality_level_get)
+		return 0;
+	ret = ops->clock_quality_level_get(dpll, dpll_priv(dpll), qls, extack);
+	if (ret)
+		return ret;
+	for_each_set_bit(ql, qls, DPLL_CLOCK_QUALITY_LEVEL_MAX)
+		if (nla_put_u32(msg, DPLL_A_CLOCK_QUALITY_LEVEL, ql))
+			return -EMSGSIZE;
+
+	return 0;
+}
+
 static int
 dpll_msg_add_pin_prio(struct sk_buff *msg, struct dpll_pin *pin,
 		      struct dpll_pin_ref *ref,
@@ -557,6 +578,9 @@ dpll_device_get_one(struct dpll_device *dpll, struct sk_buff *msg,
 	if (ret)
 		return ret;
 	ret = dpll_msg_add_lock_status(msg, dpll, extack);
+	if (ret)
+		return ret;
+	ret = dpll_msg_add_clock_quality_level(msg, dpll, extack);
 	if (ret)
 		return ret;
 	ret = dpll_msg_add_mode(msg, dpll, extack);

include/linux/dpll.h

@@ -26,6 +26,10 @@ struct dpll_device_ops {
 			       struct netlink_ext_ack *extack);
 	int (*temp_get)(const struct dpll_device *dpll, void *dpll_priv,
 			s32 *temp, struct netlink_ext_ack *extack);
+	int (*clock_quality_level_get)(const struct dpll_device *dpll,
+				       void *dpll_priv,
+				       unsigned long *qls,
+				       struct netlink_ext_ack *extack);
 };
 
 struct dpll_pin_ops {

include/uapi/linux/dpll.h

@@ -79,6 +79,29 @@ enum dpll_lock_status_error {
 	DPLL_LOCK_STATUS_ERROR_MAX = (__DPLL_LOCK_STATUS_ERROR_MAX - 1)
 };
 
+/**
+ * enum dpll_clock_quality_level - level of quality of a clock device. This
+ *   mainly applies when the dpll lock-status is DPLL_LOCK_STATUS_HOLDOVER. The
+ *   current list is defined according to the table 11-7 contained in ITU-T
+ *   G.8264/Y.1364 document. One may extend this list freely by other ITU-T
+ *   defined clock qualities, or different ones defined by another
+ *   standardization body (for those, please use different prefix).
+ */
+enum dpll_clock_quality_level {
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_PRC = 1,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_SSU_A,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_SSU_B,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_EEC1,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_PRTC,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_EPRTC,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_EEEC,
+	DPLL_CLOCK_QUALITY_LEVEL_ITU_OPT1_EPRC,
+
+	/* private: */
+	__DPLL_CLOCK_QUALITY_LEVEL_MAX,
+	DPLL_CLOCK_QUALITY_LEVEL_MAX = (__DPLL_CLOCK_QUALITY_LEVEL_MAX - 1)
+};
+
 #define DPLL_TEMP_DIVIDER	1000
 
 /**
@@ -180,6 +203,7 @@ enum dpll_a {
 	DPLL_A_TEMP,
 	DPLL_A_TYPE,
 	DPLL_A_LOCK_STATUS_ERROR,
+	DPLL_A_CLOCK_QUALITY_LEVEL,
 
 	__DPLL_A_MAX,
 	DPLL_A_MAX = (__DPLL_A_MAX - 1)