Add new callback operations for a dpll device:
- phase_offset_avg_factor_get(...) - to obtain current phase offset
  averaging factor from dpll device,
- phase_offset_avg_factor_set(...) - to set phase offset averaging factor

Obtain the factor value using the get callback and provide it to the user
if the device driver implements callbacks. Execute the set callback upon
user requests.

Signed-off-by: Ivan Vecera <ivecera@redhat.com>
---
 drivers/dpll/dpll_netlink.c | 76 +++++++++++++++++++++++++++++++++----
 include/linux/dpll.h        |  6 +++
 2 files changed, 75 insertions(+), 7 deletions(-)

diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index 0a852011653c4..55b3ffe08024b 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -164,6 +164,28 @@ dpll_msg_add_phase_offset_monitor(struct sk_buff *msg, struct dpll_device *dpll,
 	return 0;
 }
 
+static int
+dpll_msg_add_phase_offset_avg_factor(struct sk_buff *msg,
+				     struct dpll_device *dpll,
+				     struct netlink_ext_ack *extack)
+{
+	const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+	u32 factor;
+	int ret;
+
+	if (ops->phase_offset_avg_factor_set &&
+	    ops->phase_offset_avg_factor_get) {
+		ret = ops->phase_offset_avg_factor_get(dpll, dpll_priv(dpll),
+						       &factor, extack);
+		if (ret)
+			return ret;
+		if (nla_put_u32(msg, DPLL_A_PHASE_OFFSET_AVG_FACTOR, factor))
+			return -EMSGSIZE;
+	}
+
+	return 0;
+}
+
 static int
 dpll_msg_add_lock_status(struct sk_buff *msg, struct dpll_device *dpll,
 			 struct netlink_ext_ack *extack)
@@ -675,6 +697,9 @@ dpll_device_get_one(struct dpll_device *dpll, struct sk_buff *msg,
 	if (nla_put_u32(msg, DPLL_A_TYPE, dpll->type))
 		return -EMSGSIZE;
 	ret = dpll_msg_add_phase_offset_monitor(msg, dpll, extack);
+	if (ret)
+		return ret;
+	ret = dpll_msg_add_phase_offset_avg_factor(msg, dpll, extack);
 	if (ret)
 		return ret;
 
@@ -839,6 +864,32 @@ dpll_phase_offset_monitor_set(struct dpll_device *dpll, struct nlattr *a,
 					     extack);
 }
 
+static int
+dpll_phase_offset_avg_factor_set(struct dpll_device *dpll, struct nlattr *a,
+				 struct netlink_ext_ack *extack)
+{
+	const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+	u32 factor = nla_get_u32(a), old_factor;
+	int ret;
+
+	if (!(ops->phase_offset_avg_factor_set &&
+	      ops->phase_offset_avg_factor_get)) {
+		NL_SET_ERR_MSG_ATTR(extack, a, "dpll device not capable of phase offset averaging");
+		return -EOPNOTSUPP;
+	}
+	ret = ops->phase_offset_avg_factor_get(dpll, dpll_priv(dpll),
+					       &old_factor, extack);
+	if (ret) {
+		NL_SET_ERR_MSG(extack, "unable to get current phase offset averaging factor");
+		return ret;
+	}
+	if (factor == old_factor)
+		return 0;
+
+	return ops->phase_offset_avg_factor_set(dpll, dpll_priv(dpll), factor,
+						extack);
+}
+
 static int
 dpll_pin_freq_set(struct dpll_pin *pin, struct nlattr *a,
 		  struct netlink_ext_ack *extack)
@@ -1736,14 +1787,25 @@ int dpll_nl_device_get_doit(struct sk_buff *skb, struct genl_info *info)
 static int
 dpll_set_from_nlattr(struct dpll_device *dpll, struct genl_info *info)
 {
-	int ret;
-
-	if (info->attrs[DPLL_A_PHASE_OFFSET_MONITOR]) {
-		struct nlattr *a = info->attrs[DPLL_A_PHASE_OFFSET_MONITOR];
+	struct nlattr *a;
+	int rem, ret;
 
-		ret = dpll_phase_offset_monitor_set(dpll, a, info->extack);
-		if (ret)
-			return ret;
+	nla_for_each_attr(a, genlmsg_data(info->genlhdr),
+			  genlmsg_len(info->genlhdr), rem) {
+		switch (nla_type(a)) {
+		case DPLL_A_PHASE_OFFSET_MONITOR:
+			ret = dpll_phase_offset_monitor_set(dpll, a,
+							    info->extack);
+			if (ret)
+				return ret;
+			break;
+		case DPLL_A_PHASE_OFFSET_AVG_FACTOR:
+			ret = dpll_phase_offset_avg_factor_set(dpll, a,
+							       info->extack);
+			if (ret)
+				return ret;
+			break;
+		}
 	}
 
 	return 0;
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index fa1e76920d0ee..25be745bf41f1 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -38,6 +38,12 @@ struct dpll_device_ops {
 					void *dpll_priv,
 					enum dpll_feature_state *state,
 					struct netlink_ext_ack *extack);
+	int (*phase_offset_avg_factor_set)(const struct dpll_device *dpll,
+					   void *dpll_priv, u32 factor,
+					   struct netlink_ext_ack *extack);
+	int (*phase_offset_avg_factor_get)(const struct dpll_device *dpll,
+					   void *dpll_priv, u32 *factor,
+					   struct netlink_ext_ack *extack);
 };
 
 struct dpll_pin_ops {
-- 
2.49.1