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
22 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
23 MODULE_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 */
of_mdiobus_register(struct mii_bus * mdio,struct device_node * np)33 int 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 *paddr;
56 u32 addr;
57 int len;
58
59 /* A PHY must have a reg property in the range [0-31] */
60 paddr = of_get_property(child, "reg", &len);
61 if (!paddr || len < sizeof(*paddr)) {
62 dev_err(&mdio->dev, "%s has invalid PHY address\n",
63 child->full_name);
64 continue;
65 }
66
67 addr = be32_to_cpup(paddr);
68 if (addr >= 32) {
69 dev_err(&mdio->dev, "%s PHY address %i is too large\n",
70 child->full_name, addr);
71 continue;
72 }
73
74 if (mdio->irq) {
75 mdio->irq[addr] = irq_of_parse_and_map(child, 0);
76 if (!mdio->irq[addr])
77 mdio->irq[addr] = PHY_POLL;
78 }
79
80 phy = get_phy_device(mdio, addr);
81 if (!phy || IS_ERR(phy)) {
82 dev_err(&mdio->dev, "error probing PHY at address %i\n",
83 addr);
84 continue;
85 }
86
87 /* Associate the OF node with the device structure so it
88 * can be looked up later */
89 of_node_get(child);
90 phy->dev.of_node = child;
91
92 /* All data is now stored in the phy struct; register it */
93 rc = phy_device_register(phy);
94 if (rc) {
95 phy_device_free(phy);
96 of_node_put(child);
97 continue;
98 }
99
100 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
101 child->name, addr);
102 }
103
104 return 0;
105 }
106 EXPORT_SYMBOL(of_mdiobus_register);
107
108 /* Helper function for of_phy_find_device */
of_phy_match(struct device * dev,void * phy_np)109 static int of_phy_match(struct device *dev, void *phy_np)
110 {
111 return dev->of_node == phy_np;
112 }
113
114 /**
115 * of_phy_find_device - Give a PHY node, find the phy_device
116 * @phy_np: Pointer to the phy's device tree node
117 *
118 * Returns a pointer to the phy_device.
119 */
of_phy_find_device(struct device_node * phy_np)120 struct phy_device *of_phy_find_device(struct device_node *phy_np)
121 {
122 struct device *d;
123 if (!phy_np)
124 return NULL;
125
126 d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
127 return d ? to_phy_device(d) : NULL;
128 }
129 EXPORT_SYMBOL(of_phy_find_device);
130
131 /**
132 * of_phy_connect - Connect to the phy described in the device tree
133 * @dev: pointer to net_device claiming the phy
134 * @phy_np: Pointer to device tree node for the PHY
135 * @hndlr: Link state callback for the network device
136 * @iface: PHY data interface type
137 *
138 * Returns a pointer to the phy_device if successful. NULL otherwise
139 */
of_phy_connect(struct net_device * dev,struct device_node * phy_np,void (* hndlr)(struct net_device *),u32 flags,phy_interface_t iface)140 struct phy_device *of_phy_connect(struct net_device *dev,
141 struct device_node *phy_np,
142 void (*hndlr)(struct net_device *), u32 flags,
143 phy_interface_t iface)
144 {
145 struct phy_device *phy = of_phy_find_device(phy_np);
146
147 if (!phy)
148 return NULL;
149
150 return phy_connect_direct(dev, phy, hndlr, flags, iface) ? NULL : phy;
151 }
152 EXPORT_SYMBOL(of_phy_connect);
153
154 /**
155 * of_phy_connect_fixed_link - Parse fixed-link property and return a dummy phy
156 * @dev: pointer to net_device claiming the phy
157 * @hndlr: Link state callback for the network device
158 * @iface: PHY data interface type
159 *
160 * This function is a temporary stop-gap and will be removed soon. It is
161 * only to support the fs_enet, ucc_geth and gianfar Ethernet drivers. Do
162 * not call this function from new drivers.
163 */
of_phy_connect_fixed_link(struct net_device * dev,void (* hndlr)(struct net_device *),phy_interface_t iface)164 struct phy_device *of_phy_connect_fixed_link(struct net_device *dev,
165 void (*hndlr)(struct net_device *),
166 phy_interface_t iface)
167 {
168 struct device_node *net_np;
169 char bus_id[MII_BUS_ID_SIZE + 3];
170 struct phy_device *phy;
171 const __be32 *phy_id;
172 int sz;
173
174 if (!dev->dev.parent)
175 return NULL;
176
177 net_np = dev->dev.parent->of_node;
178 if (!net_np)
179 return NULL;
180
181 phy_id = of_get_property(net_np, "fixed-link", &sz);
182 if (!phy_id || sz < sizeof(*phy_id))
183 return NULL;
184
185 sprintf(bus_id, PHY_ID_FMT, "fixed-0", be32_to_cpu(phy_id[0]));
186
187 phy = phy_connect(dev, bus_id, hndlr, 0, iface);
188 return IS_ERR(phy) ? NULL : phy;
189 }
190 EXPORT_SYMBOL(of_phy_connect_fixed_link);
191