phy: introduce phy_get_by_index

The upstream (v5.6-rc1) device tree node of the stm32mp157c-dk2's OHCI
has a phys property, but not phy-names. We have no API to reference
such a phy easily (passing NULL isn't allowed). Add one.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 14 insertions, 0 deletions

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index ad1e814788..ff6e35d160 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -371,3 +371,17 @@ struct phy *phy_optional_get(struct device_d *dev, const char *string)
 	return phy;
 }
 
+/**
+ * phy_get_by_index() - lookup and obtain a reference to a phy by index.
+ * @dev: device with node that references this phy
+ * @index: index of the phy
+ *
+ * Gets the phy using _of_phy_get()
+ */
+struct phy *phy_get_by_index(struct device_d *dev, int index)
+{
+	if (!dev->device_node)
+		return ERR_PTR(-ENODEV);
+
+	return _of_phy_get(dev->device_node, index);
+}