[PATCH/RFC 2/3] ethernet: add a PHY reset GPIO DT binding to sh_eth

[Guennadi Liakhovetski]

If an ethernet PHY can be reset by a GPIO, it can be specified in DT. Add
a binding and code to parse it, request the GPIO and take the PHY out of
reset.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski at gmx.de>
Cc: devicetree-discuss at lists.ozlabs.org
Cc: netdev at vger.kernel.org
---
 Documentation/devicetree/bindings/net/sh_ether.txt |    2 ++
 drivers/net/ethernet/renesas/sh_eth.c              |    9 ++++++++-
 2 files changed, 10 insertions(+), 1 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/sh_ether.txt b/Documentation/devicetree/bindings/net/sh_ether.txt
index c11e45d..edaf683 100644
--- a/Documentation/devicetree/bindings/net/sh_ether.txt
+++ b/Documentation/devicetree/bindings/net/sh_ether.txt
@@ -12,6 +12,7 @@ Required properties:
 - interrupts:                   Interrupt mapping for the sh_eth interrupt
                                 sources (vector id).
 - phy-mode:              String, operation mode of the PHY interface.
+- phy-reset-gpios:              PHY reset GPIO tuple
 - sh-eth,edmac-endian:          String, endian of sh_eth dmac.
 - sh-eth,register-type:         String, register type of sh_eth.
                                 Please select "gigabit", "fast-sh4" or
@@ -37,6 +38,7 @@ Example (armadillo800eva):
 		reg = <0xe9a00000 0x800>, <0xe9a01800 0x800>;
 		interrupts = <0x500>;
 		phy-mode = "mii";
+		phy-reset-gpios = <&gpio 18 0>;
 		sh-eth,edmac-endian = "little";
 		sh-eth,register-type = "gigabit";
 		sh-eth,phy-id = <0>;
diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index 1f64848..06035a2 100644
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -20,6 +20,7 @@
  *  the file called "COPYING".
  */
 
+#include <linux/gpio.h>
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/kernel.h>
@@ -33,6 +34,7 @@
 #include <linux/netdevice.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
+#include <linux/of_gpio.h>
 #include <linux/of_platform.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
@@ -2376,10 +2378,11 @@ sh_eth_of_get_register_type(struct device_node *np)
 static struct sh_eth_plat_data *
 sh_eth_parse_dt(struct device *dev, struct net_device *ndev)
 {
-	int ret;
+	int ret, gpio;
 	const char *of_str;
 	struct device_node *np = dev->of_node;
 	struct sh_eth_plat_data *pdata;
+	enum of_gpio_flags flags;
 
 	pdata = devm_kzalloc(dev, sizeof(struct sh_eth_plat_data),
 					GFP_KERNEL);
@@ -2420,6 +2423,10 @@ sh_eth_parse_dt(struct device *dev, struct net_device *ndev)
 	else
 		pdata->needs_init = 0;
 
+	gpio = of_get_named_gpio_flags(np, "phy-reset-gpios", 0, &flags);
+	if (gpio_is_valid(gpio) && !devm_gpio_request(dev, gpio, NULL))
+		gpio_direction_output(gpio, !!(flags & OF_GPIO_ACTIVE_LOW));
+
 #ifdef CONFIG_OF_NET
 	if (!is_valid_ether_addr(ndev->dev_addr)) {
 		const char *macaddr = of_get_mac_address(np);
-- 
1.7.2.5