[PATCH net-next v5 2/3] dpll: add phase_offset_monitor_get/set callback ops

[Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>]

Add new callback operations for a dpll device:
- phase_offset_monitor_get(..) - to obtain current state of phase offset
  monitor feature from dpll device,
- phase_offset_monitor_set(..) - to allow feature configuration.

Obtain the feature state value using the get callback and provide it to
the user if the device driver implements callbacks.

Execute the set callback upon user requests.

Reviewed-by: Milena Olech <milena.olech@intel.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Arkadiusz Kubalewski <arkadiusz.kubalewski@intel.com>
---
v5:
- rebase.
---
 drivers/dpll/dpll_netlink.c | 69 +++++++++++++++++++++++++++++++++++--
 include/linux/dpll.h        |  8 +++++
 2 files changed, 75 insertions(+), 2 deletions(-)

diff --git a/drivers/dpll/dpll_netlink.c b/drivers/dpll/dpll_netlink.c
index c130f87147fa..4619aaa18b9c 100644
--- a/drivers/dpll/dpll_netlink.c
+++ b/drivers/dpll/dpll_netlink.c
@@ -126,6 +126,26 @@ dpll_msg_add_mode_supported(struct sk_buff *msg, struct dpll_device *dpll,
 	return 0;
 }
 
+static int
+dpll_msg_add_phase_offset_monitor(struct sk_buff *msg, struct dpll_device *dpll,
+				  struct netlink_ext_ack *extack)
+{
+	const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+	enum dpll_feature_state state;
+	int ret;
+
+	if (ops->phase_offset_monitor_set && ops->phase_offset_monitor_get) {
+		ret = ops->phase_offset_monitor_get(dpll, dpll_priv(dpll),
+						    &state, extack);
+		if (ret)
+			return ret;
+		if (nla_put_u32(msg, DPLL_A_PHASE_OFFSET_MONITOR, state))
+			return -EMSGSIZE;
+	}
+
+	return 0;
+}
+
 static int
 dpll_msg_add_lock_status(struct sk_buff *msg, struct dpll_device *dpll,
 			 struct netlink_ext_ack *extack)
@@ -591,6 +611,9 @@ dpll_device_get_one(struct dpll_device *dpll, struct sk_buff *msg,
 		return ret;
 	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;
 
 	return 0;
 }
@@ -746,6 +769,31 @@ int dpll_pin_change_ntf(struct dpll_pin *pin)
 }
 EXPORT_SYMBOL_GPL(dpll_pin_change_ntf);
 
+static int
+dpll_phase_offset_monitor_set(struct dpll_device *dpll, struct nlattr *a,
+			      struct netlink_ext_ack *extack)
+{
+	const struct dpll_device_ops *ops = dpll_device_ops(dpll);
+	enum dpll_feature_state state = nla_get_u32(a), old_state;
+	int ret;
+
+	if (!(ops->phase_offset_monitor_set && ops->phase_offset_monitor_get)) {
+		NL_SET_ERR_MSG_ATTR(extack, a, "dpll device not capable of phase offset monitor");
+		return -EOPNOTSUPP;
+	}
+	ret = ops->phase_offset_monitor_get(dpll, dpll_priv(dpll), &old_state,
+					    extack);
+	if (ret) {
+		NL_SET_ERR_MSG(extack, "unable to get current state of phase offset monitor");
+		return ret;
+	}
+	if (state == old_state)
+		return 0;
+
+	return ops->phase_offset_monitor_set(dpll, dpll_priv(dpll), state,
+					     extack);
+}
+
 static int
 dpll_pin_freq_set(struct dpll_pin *pin, struct nlattr *a,
 		  struct netlink_ext_ack *extack)
@@ -1533,10 +1581,27 @@ int dpll_nl_device_get_doit(struct sk_buff *skb, struct genl_info *info)
 	return genlmsg_reply(msg, 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];
+
+		ret = dpll_phase_offset_monitor_set(dpll, a, info->extack);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
 int dpll_nl_device_set_doit(struct sk_buff *skb, struct genl_info *info)
 {
-	/* placeholder for set command */
-	return 0;
+	struct dpll_device *dpll = info->user_ptr[0];
+
+	return dpll_set_from_nlattr(dpll, info);
 }
 
 int dpll_nl_device_get_dumpit(struct sk_buff *skb, struct netlink_callback *cb)
diff --git a/include/linux/dpll.h b/include/linux/dpll.h
index 5e4f9ab1cf75..6ad6c2968a28 100644
--- a/include/linux/dpll.h
+++ b/include/linux/dpll.h
@@ -30,6 +30,14 @@ struct dpll_device_ops {
 				       void *dpll_priv,
 				       unsigned long *qls,
 				       struct netlink_ext_ack *extack);
+	int (*phase_offset_monitor_set)(const struct dpll_device *dpll,
+					void *dpll_priv,
+					enum dpll_feature_state state,
+					struct netlink_ext_ack *extack);
+	int (*phase_offset_monitor_get)(const struct dpll_device *dpll,
+					void *dpll_priv,
+					enum dpll_feature_state *state,
+					struct netlink_ext_ack *extack);
 };
 
 struct dpll_pin_ops {
-- 
2.38.1