[PATCH v7 3/5] phy: core: Add support for phy suspend & resume

[Krishna chaitanya chundru <quic_krichai@quicinc.com>]

Introducing phy power suspend and resume callbacks for allowing to
park the link-state in L1ss without holding any PCIe resources during
system suspend.

If we use  phy_suspend & phy_resume API's we are getting compilation
issue as same function is present in drivers/net/phy/phy_device.c.

So creating phy_pm_suspend & phy_pm_resume API's.

Signed-off-by: Krishna chaitanya chundru <quic_krichai@quicinc.com>
---
changes since v6:
	- change names from power_down, power_up to suspend & resume
	  respectively.
---
 drivers/phy/phy-core.c  | 30 ++++++++++++++++++++++++++++++
 include/linux/phy/phy.h | 20 ++++++++++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index d93ddf1..ca3e423 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -441,6 +441,36 @@ int phy_set_speed(struct phy *phy, int speed)
 }
 EXPORT_SYMBOL_GPL(phy_set_speed);
 
+int phy_pm_suspend(struct phy *phy)
+{
+	int ret;
+
+	if (!phy || !phy->ops->suspend)
+		return 0;
+
+	mutex_lock(&phy->mutex);
+	ret = phy->ops->suspend(phy);
+	mutex_unlock(&phy->mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(phy_pm_suspend);
+
+int phy_pm_resume(struct phy *phy)
+{
+	int ret;
+
+	if (!phy || !phy->ops->resume)
+		return 0;
+
+	mutex_lock(&phy->mutex);
+	ret = phy->ops->resume(phy);
+	mutex_unlock(&phy->mutex);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(phy_pm_resume);
+
 int phy_reset(struct phy *phy)
 {
 	int ret;
diff --git a/include/linux/phy/phy.h b/include/linux/phy/phy.h
index b141375..e312028 100644
--- a/include/linux/phy/phy.h
+++ b/include/linux/phy/phy.h
@@ -76,6 +76,8 @@ union phy_configure_opts {
  * @set_mode: set the mode of the phy
  * @set_media: set the media type of the phy (optional)
  * @set_speed: set the speed of the phy (optional)
+ * @suspend: suspending the phy
+ * @resume: resuming the phy
  * @reset: resetting the phy
  * @calibrate: calibrate the phy
  * @release: ops to be performed while the consumer relinquishes the PHY
@@ -89,6 +91,8 @@ struct phy_ops {
 	int	(*set_mode)(struct phy *phy, enum phy_mode mode, int submode);
 	int	(*set_media)(struct phy *phy, enum phy_media media);
 	int	(*set_speed)(struct phy *phy, int speed);
+	int	(*suspend)(struct phy *phy);
+	int	(*resume)(struct phy *phy);
 
 	/**
 	 * @configure:
@@ -226,6 +230,8 @@ int phy_init(struct phy *phy);
 int phy_exit(struct phy *phy);
 int phy_power_on(struct phy *phy);
 int phy_power_off(struct phy *phy);
+int phy_pm_suspend(struct phy *phy);
+int phy_pm_resume(struct phy *phy);
 int phy_set_mode_ext(struct phy *phy, enum phy_mode mode, int submode);
 #define phy_set_mode(phy, mode) \
 	phy_set_mode_ext(phy, mode, 0)
@@ -349,6 +355,20 @@ static inline int phy_power_off(struct phy *phy)
 	return -ENOSYS;
 }
 
+static inline int phy_pm_suspend(struct phy *phy)
+{
+	if (!phy)
+		return 0;
+	return -ENOSYS;
+}
+
+static inline int phy_pm_resume(struct phy *phy)
+{
+	if (!phy)
+		return 0;
+	return -ENOSYS;
+}
+
 static inline int phy_set_mode_ext(struct phy *phy, enum phy_mode mode,
 				   int submode)
 {
-- 
2.7.4