1/*
2 * OF helpers for the MDIO (Ethernet PHY) API
3 *
4 * Copyright (c) 2009 Secret Lab Technologies, Ltd.
5 *
6 * This file is released under the GPLv2
7 *
8 * This file provides helper functions for extracting PHY device information
9 * out of the OpenFirmware device tree and using it to populate an mii_bus.
10 */
11
12#include <linux/kernel.h>
13#include <linux/device.h>
14#include <linux/netdevice.h>
15#include <linux/err.h>
16#include <linux/phy.h>
17#include <linux/of.h>
18#include <linux/of_irq.h>
19#include <linux/of_mdio.h>
20#include <linux/module.h>
21
22MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
23MODULE_LICENSE("GPL");
24
25/**
26 * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
27 * @mdio: pointer to mii_bus structure
28 * @np: pointer to device_node of MDIO bus.
29 *
30 * This function registers the mii_bus structure and registers a phy_device
31 * for each child node of @np.
32 */
33int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
34{
35	struct phy_device *phy;
36	struct device_node *child;
37	int rc, i;
38
39	/* Mask out all PHYs from auto probing.  Instead the PHYs listed in
40	 * the device tree are populated after the bus has been registered */
41	mdio->phy_mask = ~0;
42
43	/* Clear all the IRQ properties */
44	if (mdio->irq)
45		for (i=0; i<PHY_MAX_ADDR; i++)
46			mdio->irq[i] = PHY_POLL;
47
48	/* Register the MDIO bus */
49	rc = mdiobus_register(mdio);
50	if (rc)
51		return rc;
52
53	/* Loop over the child nodes and register a phy_device for each one */
54	for_each_child_of_node(np, child) {
55		const __be32 *addr;
56		int len;
57
58		/* A PHY must have a reg property in the range [0-31] */
59		addr = of_get_property(child, "reg", &len);
60		if (!addr || len < sizeof(*addr) || *addr >= 32 || *addr < 0) {
61			dev_err(&mdio->dev, "%s has invalid PHY address\n",
62				child->full_name);
63			continue;
64		}
65
66		if (mdio->irq) {
67			mdio->irq[*addr] = irq_of_parse_and_map(child, 0);
68			if (!mdio->irq[*addr])
69				mdio->irq[*addr] = PHY_POLL;
70		}
71
72		phy = get_phy_device(mdio, be32_to_cpup(addr));
73		if (!phy || IS_ERR(phy)) {
74			dev_err(&mdio->dev, "error probing PHY at address %i\n",
75				*addr);
76			continue;
77		}
78		phy_scan_fixups(phy);
79
80		/* Associate the OF node with the device structure so it
81		 * can be looked up later */
82		of_node_get(child);
83		phy->dev.of_node = child;
84
85		/* All data is now stored in the phy struct; register it */
86		rc = phy_device_register(phy);
87		if (rc) {
88			phy_device_free(phy);
89			of_node_put(child);
90			continue;
91		}
92
93		dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
94			child->name, *addr);
95	}
96
97	return 0;
98}
99EXPORT_SYMBOL(of_mdiobus_register);
100
101/* Helper function for of_phy_find_device */
102static int of_phy_match(struct device *dev, void *phy_np)
103{
104	return dev->of_node == phy_np;
105}
106
107/**
108 * of_phy_find_device - Give a PHY node, find the phy_device
109 * @phy_np: Pointer to the phy's device tree node
110 *
111 * Returns a pointer to the phy_device.
112 */
113struct phy_device *of_phy_find_device(struct device_node *phy_np)
114{
115	struct device *d;
116	if (!phy_np)
117		return NULL;
118
119	d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
120	return d ? to_phy_device(d) : NULL;
121}
122EXPORT_SYMBOL(of_phy_find_device);
123
124/**
125 * of_phy_connect - Connect to the phy described in the device tree
126 * @dev: pointer to net_device claiming the phy
127 * @phy_np: Pointer to device tree node for the PHY
128 * @hndlr: Link state callback for the network device
129 * @iface: PHY data interface type
130 *
131 * Returns a pointer to the phy_device if successfull.  NULL otherwise
132 */
133struct phy_device *of_phy_connect(struct net_device *dev,
134				  struct device_node *phy_np,
135				  void (*hndlr)(struct net_device *), u32 flags,
136				  phy_interface_t iface)
137{
138	struct phy_device *phy = of_phy_find_device(phy_np);
139
140	if (!phy)
141		return NULL;
142
143	return phy_connect_direct(dev, phy, hndlr, flags, iface) ? NULL : phy;
144}
145EXPORT_SYMBOL(of_phy_connect);
146
147/**
148 * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
149 * @dev: pointer to net_device claiming the phy
150 * @hndlr: Link state callback for the network device
151 * @iface: PHY data interface type
152 *
153 * This function is a temporary stop-gap and will be removed soon.  It is
154 * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers.  Do
155 * not call this function from new drivers.
156 */
157struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
158					     void (*hndlr)(struct net_device *),
159					     phy_interface_t iface)
160{
161	struct device_node *net_np;
162	char bus_id[MII_BUS_ID_SIZE + 3];
163	struct phy_device *phy;
164	const __be32 *phy_id;
165	int sz;
166
167	if (!dev->dev.parent)
168		return NULL;
169
170	net_np = dev->dev.parent->of_node;
171	if (!net_np)
172		return NULL;
173
174	phy_id = of_get_property(net_np, "fixed-link", &sz);
175	if (!phy_id || sz < sizeof(*phy_id))
176		return NULL;
177
178	sprintf(bus_id, PHY_ID_FMT, "0", be32_to_cpu(phy_id[0]));
179
180	phy = phy_connect(dev, bus_id, hndlr, 0, iface);
181	return IS_ERR(phy) ? NULL : phy;
182}
183EXPORT_SYMBOL(of_phy_connect_fixed_link);
184