phy: Add devm_of_phy_optional_get() helper

Add an optional variant of devm_of_phy_get() that also takes care of
printing real errors, so drivers no longer have to open-code this
operation.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/4cd0069bcff424ffc5c3a102397c02370b91985b.1674584626.git.geert+renesas@glider.be
Signed-off-by: Vinod Koul <vkoul@kernel.org>

1 files changed, 30 insertions, 0 deletions

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 672f5c865886..9951efc03eaa 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -859,6 +859,36 @@ struct phy *devm_of_phy_get(struct device *dev, struct device_node *np,
 EXPORT_SYMBOL_GPL(devm_of_phy_get);
 
 /**
+ * devm_of_phy_optional_get() - lookup and obtain a reference to an optional
+ * phy.
+ * @dev: device that requests this phy
+ * @np: node containing the phy
+ * @con_id: name of the phy from device's point of view
+ *
+ * Gets the phy using of_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_of_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_of_phy_optional_get(struct device *dev, struct device_node *np,
+				     const char *con_id)
+{
+	struct phy *phy = devm_of_phy_get(dev, np, con_id);
+
+	if (PTR_ERR(phy) == -ENODEV)
+		phy = NULL;
+
+	if (IS_ERR(phy))
+		dev_err_probe(dev, PTR_ERR(phy), "failed to get PHY %pOF:%s",
+			      np, con_id);
+
+	return phy;
+}
+EXPORT_SYMBOL_GPL(devm_of_phy_optional_get);
+
+/**
  * devm_of_phy_get_by_index() - lookup and obtain a reference to a phy by index.
  * @dev: device that requests this phy
  * @np: node containing the phy