sh_eth: add device tree support

Add support of the device tree probing for the Renesas SH-Mobile SoCs
documenting the device tree binding as necessary.

This work is loosely based on the original patch by Nobuhiro Iwamatsu
<[e-mail]>.

Signed-off-by: Sergei Shtylyov <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/devicetree/bindings/net/sh_eth.txt

···
+* Renesas Electronics SH EtherMAC
+
+This file provides information on what the device node for the SH EtherMAC
+interface contains.
+
+Required properties:
+- compatible: "renesas,gether-r8a7740" if the device is a part of R8A7740 SoC.
+	      "renesas,ether-r8a7778"  if the device is a part of R8A7778 SoC.
+	      "renesas,ether-r8a7779"  if the device is a part of R8A7779 SoC.
+	      "renesas,ether-r8a7790"  if the device is a part of R8A7790 SoC.
+	      "renesas,ether-r8a7791"  if the device is a part of R8A7791 SoC.
+	      "renesas,ether-r7s72100" if the device is a part of R7S72100 SoC.
+- reg: offset and length of (1) the E-DMAC/feLic register block (required),
+       (2) the TSU register block (optional).
+- interrupts: interrupt specifier for the sole interrupt.
+- phy-mode: see ethernet.txt file in the same directory.
+- phy-handle: see ethernet.txt file in the same directory.
+- #address-cells: number of address cells for the MDIO bus, must be equal to 1.
+- #size-cells: number of size cells on the MDIO bus, must be equal to 0.
+- clocks: clock phandle and specifier pair.
+- pinctrl-0: phandle, referring to a default pin configuration node.
+
+Optional properties:
+- interrupt-parent: the phandle for the interrupt controller that services
+		    interrupts for this device.
+- pinctrl-names: pin configuration state name ("default").
+- renesas,no-ether-link: boolean, specify when a board does not provide a proper
+			 Ether LINK signal.
+- renesas,ether-link-active-low: boolean, specify when the Ether LINK signal is
+				 active-low instead of normal active-high.
+
+Example (Lager board):
+
+	ethernet@ee700000 {
+		compatible = "renesas,ether-r8a7790";
+		reg = <0 0xee700000 0 0x400>;
+		interrupt-parent = <&gic>;
+		interrupts = <0 162 IRQ_TYPE_LEVEL_HIGH>;
+		clocks = <&mstp8_clks R8A7790_CLK_ETHER>;
+		phy-mode = "rmii";
+		phy-handle = <&phy1>;
+		pinctrl-0 = <&ether_pins>;
+		pinctrl-names = "default";
+		renesas,ether-link-active-low;
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		phy1: ethernet-phy@1 {
+			reg = <1>;
+			interrupt-parent = <&irqc0>;
+			interrupts = <0 IRQ_TYPE_LEVEL_LOW>;
+			pinctrl-0 = <&phy1_pins>;
+			pinctrl-names = "default";
+		};
+	};

drivers/net/ethernet/renesas/sh_eth.c

···
 /*  SuperH Ethernet device driver
  *
  *  Copyright (C) 2006-2012 Nobuhiro Iwamatsu
- *  Copyright (C) 2008-2013 Renesas Solutions Corp.
- *  Copyright (C) 2013 Cogent Embedded, Inc.
+ *  Copyright (C) 2008-2014 Renesas Solutions Corp.
+ *  Copyright (C) 2013-2014 Cogent Embedded, Inc.
  *
  *  This program is free software; you can redistribute it and/or modify it
  *  under the terms and conditions of the GNU General Public License,
···
 #include <linux/platform_device.h>
 #include <linux/mdio-bitbang.h>
 #include <linux/netdevice.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_irq.h>
+#include <linux/of_net.h>
 #include <linux/phy.h>
 #include <linux/cache.h>
 #include <linux/io.h>
···
 	.ndo_change_mtu		= eth_change_mtu,
 };
 
+#ifdef CONFIG_OF
+static struct sh_eth_plat_data *sh_eth_parse_dt(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct sh_eth_plat_data *pdata;
+	struct device_node *phy;
+	const char *mac_addr;
+
+	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+	if (!pdata)
+		return NULL;
+
+	pdata->phy_interface = of_get_phy_mode(np);
+
+	phy = of_parse_phandle(np, "phy-handle", 0);
+	if (of_property_read_u32(phy, "reg", &pdata->phy))
+		return NULL;
+	pdata->phy_irq = irq_of_parse_and_map(phy, 0);
+
+	mac_addr = of_get_mac_address(np);
+	if (mac_addr)
+		memcpy(pdata->mac_addr, mac_addr, ETH_ALEN);
+
+	pdata->no_ether_link =
+		of_property_read_bool(np, "renesas,no-ether-link");
+	pdata->ether_link_active_low =
+		of_property_read_bool(np, "renesas,ether-link-active-low");
+
+	return pdata;
+}
+
+static const struct of_device_id sh_eth_match_table[] = {
+	{ .compatible = "renesas,gether-r8a7740", .data = &r8a7740_data },
+	{ .compatible = "renesas,ether-r8a7778", .data = &r8a777x_data },
+	{ .compatible = "renesas,ether-r8a7779", .data = &r8a777x_data },
+	{ .compatible = "renesas,ether-r8a7790", .data = &r8a779x_data },
+	{ .compatible = "renesas,ether-r8a7791", .data = &r8a779x_data },
+	{ .compatible = "renesas,ether-r7s72100", .data = &r7s72100_data },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sh_eth_match_table);
+#else
+static inline struct sh_eth_plat_data *sh_eth_parse_dt(struct device *dev)
+{
+	return NULL;
+}
+#endif
+
 static int sh_eth_drv_probe(struct platform_device *pdev)
 {
 	int ret, devno = 0;
···
 	pm_runtime_enable(&pdev->dev);
 	pm_runtime_resume(&pdev->dev);
 
+	if (pdev->dev.of_node)
+		pd = sh_eth_parse_dt(&pdev->dev);
 	if (!pd) {
 		dev_err(&pdev->dev, "no platform data\n");
 		ret = -EINVAL;
···
 	mdp->ether_link_active_low = pd->ether_link_active_low;
 
 	/* set cpu data */
-	mdp->cd = (struct sh_eth_cpu_data *)id->driver_data;
+	if (id) {
+		mdp->cd = (struct sh_eth_cpu_data *)id->driver_data;
+	} else	{
+		const struct of_device_id *match;
+
+		match = of_match_device(of_match_ptr(sh_eth_match_table),
+					&pdev->dev);
+		mdp->cd = (struct sh_eth_cpu_data *)match->data;
+	}
 	mdp->reg_offset = sh_eth_get_register_offset(mdp->cd->register_type);
 	sh_eth_set_default_cpu_data(mdp->cd);
 
···
 	.driver = {
 		   .name = CARDNAME,
 		   .pm = SH_ETH_PM_OPS,
+		   .of_match_table = of_match_ptr(sh_eth_match_table),
 	},
 };