[PATCH net-next v1 5/6] net: dsa: microchip: use wakeup-source DT property to enable PME output

[Oleksij Rempel <o.rempel@pengutronix.de>]

KSZ switches with WoL support signals wake event over PME pin. If this
pin is attached to some external PMIC or System Controller can't be
described as GPIO, the only way to describe it in the devicetree is to
use wakeup-source property. So, add support for this property and enable
PME switch output if this property is present.

Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de>
---
 drivers/net/dsa/microchip/ksz9477.c    | 3 +++
 drivers/net/dsa/microchip/ksz_common.c | 3 +++
 drivers/net/dsa/microchip/ksz_common.h | 1 +
 3 files changed, 7 insertions(+)

diff --git a/drivers/net/dsa/microchip/ksz9477.c b/drivers/net/dsa/microchip/ksz9477.c
index 9a531db79f832..1a3d7ae5970e2 100644
--- a/drivers/net/dsa/microchip/ksz9477.c
+++ b/drivers/net/dsa/microchip/ksz9477.c
@@ -1208,6 +1208,9 @@ int ksz9477_setup(struct dsa_switch *ds)
 			return ret;
 	}
 
+	if (dev->wakeup_source)
+		ksz_write8(dev, REG_SW_PME_CTRL, PME_ENABLE);
+
 	return 0;
 }
 
diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index eb67bb520934d..354cc5333675b 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -3717,6 +3717,9 @@ int ksz_switch_register(struct ksz_device *dev)
 			dev_err(dev->dev, "inconsistent synclko settings\n");
 			return -EINVAL;
 		}
+
+		dev->wakeup_source = of_property_read_bool(dev->dev->of_node,
+							   "wakeup-source");
 	}
 
 	ret = dsa_register_switch(dev->ds);
diff --git a/drivers/net/dsa/microchip/ksz_common.h b/drivers/net/dsa/microchip/ksz_common.h
index 4ec53cf4b30be..b67bb9b4631ea 100644
--- a/drivers/net/dsa/microchip/ksz_common.h
+++ b/drivers/net/dsa/microchip/ksz_common.h
@@ -158,6 +158,7 @@ struct ksz_device {
 	phy_interface_t compat_interface;
 	bool synclko_125;
 	bool synclko_disable;
+	bool wakeup_source;
 
 	struct vlan_table *vlan_cache;
 
-- 
2.39.2