1 files changed, 67 insertions, 9 deletions

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 645c867c1257..6c738376daff 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -162,6 +162,9 @@ int phy_init(struct phy *phy)
 {
         int ret;
 
+        if (!phy)
+                return 0;
+
         ret = phy_pm_runtime_get_sync(phy);
         if (ret < 0 && ret != -ENOTSUPP)
                 return ret;
@@ -173,6 +176,8 @@ int phy_init(struct phy *phy)
                         dev_err(&phy->dev, "phy init failed --> %d\n", ret);
                         goto out;
                 }
+        } else {
+                ret = 0; /* Override possible ret == -ENOTSUPP */
         }
         ++phy->init_count;
 
@@ -187,6 +192,9 @@ int phy_exit(struct phy *phy)
 {
         int ret;
 
+        if (!phy)
+                return 0;
+
         ret = phy_pm_runtime_get_sync(phy);
         if (ret < 0 && ret != -ENOTSUPP)
                 return ret;
@@ -212,6 +220,9 @@ int phy_power_on(struct phy *phy)
 {
         int ret;
 
+        if (!phy)
+                return 0;
+
         ret = phy_pm_runtime_get_sync(phy);
         if (ret < 0 && ret != -ENOTSUPP)
                 return ret;
@@ -223,6 +234,8 @@ int phy_power_on(struct phy *phy)
                         dev_err(&phy->dev, "phy poweron failed --> %d\n", ret);
                         goto out;
                 }
+        } else {
+                ret = 0; /* Override possible ret == -ENOTSUPP */
         }
         ++phy->power_count;
         mutex_unlock(&phy->mutex);
@@ -240,6 +253,9 @@ int phy_power_off(struct phy *phy)
 {
         int ret;
 
+        if (!phy)
+                return 0;
+
         mutex_lock(&phy->mutex);
         if (phy->power_count == 1 && phy->ops->power_off) {
                 ret =  phy->ops->power_off(phy);
@@ -308,7 +324,7 @@ err0:
  */
 void phy_put(struct phy *phy)
 {
-        if (IS_ERR(phy))
+        if (!phy || IS_ERR(phy))
                 return;
 
         module_put(phy->ops->owner);
@@ -328,6 +344,9 @@ void devm_phy_put(struct device *dev, struct phy *phy)
 {
         int r;
 
+        if (!phy)
+                return;
+
         r = devres_destroy(dev, devm_phy_release, devm_phy_match, phy);
         dev_WARN_ONCE(dev, r, "couldn't find PHY resource\n");
 }
@@ -389,17 +408,11 @@ struct phy *phy_get(struct device *dev, const char *string)
                 index = of_property_match_string(dev->of_node, "phy-names",
                         string);
                 phy = of_phy_get(dev, index);
-                if (IS_ERR(phy)) {
-                        dev_err(dev, "unable to find phy\n");
-                        return phy;
-                }
         } else {
                 phy = phy_lookup(dev, string);
-                if (IS_ERR(phy)) {
-                        dev_err(dev, "unable to find phy\n");
-                        return phy;
-                }
         }
+        if (IS_ERR(phy))
+                return phy;
 
         if (!try_module_get(phy->ops->owner))
                 return ERR_PTR(-EPROBE_DEFER);
@@ -411,6 +424,27 @@ struct phy *phy_get(struct device *dev, const char *string)
 EXPORT_SYMBOL_GPL(phy_get);
 
 /**
+ * phy_optional_get() - lookup and obtain a reference to an optional phy.
+ * @dev: device that requests this phy
+ * @string: the phy name as given in the dt data or the name of the controller
+ * port for non-dt case
+ *
+ * Returns the phy driver, after getting a refcount to it; or
+ * NULL if there is no such phy.  The caller is responsible for
+ * calling phy_put() to release that count.
+ */
+struct phy *phy_optional_get(struct device *dev, const char *string)
+{
+        struct phy *phy = phy_get(dev, string);
+
+        if (PTR_ERR(phy) == -ENODEV)
+                phy = NULL;
+
+        return phy;
+}
+EXPORT_SYMBOL_GPL(phy_optional_get);
+
+/**
  * devm_phy_get() - lookup and obtain a reference to a phy.
  * @dev: device that requests this phy
  * @string: the phy name as given in the dt data or phy device name
@@ -441,6 +475,30 @@ struct phy *devm_phy_get(struct device *dev, const char *string)
 EXPORT_SYMBOL_GPL(devm_phy_get);
 
 /**
+ * devm_phy_optional_get() - lookup and obtain a reference to an optional phy.
+ * @dev: device that requests this phy
+ * @string: the phy name as given in the dt data or phy device name
+ * for non-dt case
+ *
+ * Gets the phy using phy_get(), and associates a device with it using
+ * devres. On driver detach, release function is invoked on the devres
+ * data, then, devres data is freed. This differs to devm_phy_get() in
+ * that if the phy does not exist, it is not considered an error and
+ * -ENODEV will not be returned. Instead the NULL phy is returned,
+ * which can be passed to all other phy consumer calls.
+ */
+struct phy *devm_phy_optional_get(struct device *dev, const char *string)
+{
+        struct phy *phy = devm_phy_get(dev, string);
+
+        if (PTR_ERR(phy) == -ENODEV)
+                phy = NULL;
+
+        return phy;
+}
+EXPORT_SYMBOL_GPL(devm_phy_optional_get);
+
+/**
  * phy_create() - create a new phy
  * @dev: device that is creating the new phy
  * @ops: function pointers for performing phy operations