brcm63xx: backport mdio-bus reset gpio support

Backport the mdio-bus reset gpio support from 4.12 and use it instead
of toggling the reset ourself.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/target/linux/brcm63xx/patches-4.4/001-4.13-03-mdio_bus-use-devm_gpiod_get_optional.patch b/target/linux/brcm63xx/patches-4.4/001-4.13-03-mdio_bus-use-devm_gpiod_get_optional.patch
new file mode 100644
index 0000000000..d7ac6234cf
--- /dev/null
+++ b/target/linux/brcm63xx/patches-4.4/001-4.13-03-mdio_bus-use-devm_gpiod_get_optional.patch
@@ -0,0 +1,39 @@
+From fe0e4052fb11d5c713961ab7e136520be40052a3 Mon Sep 17 00:00:00 2001
+From: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
+Date: Mon, 12 Jun 2017 23:55:39 +0300
+Subject: [PATCH] mdio_bus: use devm_gpiod_get_optional()
+
+The MDIO reset GPIO is really a classical optional GPIO property case,
+so devm_gpiod_get_optional() should have been used, not devm_gpiod_get().
+Doing this  saves several LoCs...
+
+Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+---
+ drivers/net/phy/mdio_bus.c | 14 +++++---------
+ 1 file changed, 5 insertions(+), 9 deletions(-)
+
+--- a/drivers/net/phy/mdio_bus.c
++++ b/drivers/net/phy/mdio_bus.c
+@@ -280,16 +280,12 @@ int __mdiobus_register(struct mii_bus *b
+ 	mutex_init(&bus->mdio_lock);
+ 
+ 	/* de-assert bus level PHY GPIO reset */
+-	gpiod = devm_gpiod_get(&bus->dev, "reset", GPIOD_OUT_LOW);
++	gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_LOW);
+ 	if (IS_ERR(gpiod)) {
+-		err = PTR_ERR(gpiod);
+-		if (err != -ENOENT) {
+-			dev_err(&bus->dev,
+-				"mii_bus %s couldn't get reset GPIO\n",
+-				bus->id);
+-			return err;
+-		}
+-	} else	{
++		dev_err(&bus->dev, "mii_bus %s couldn't get reset GPIO\n",
++			bus->id);
++		return PTR_ERR(gpiod);
++	} else	if (gpiod) {
+ 		bus->reset_gpiod = gpiod;
+ 
+ 		gpiod_set_value_cansleep(gpiod, 1);