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/phy_fixed.h>
18 #include <linux/of.h>
19 #include <linux/of_irq.h>
20 #include <linux/of_mdio.h>
21 #include <linux/module.h>
22
23 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
24 MODULE_LICENSE("GPL");
25
26 /* Extract the clause 22 phy ID from the compatible string of the form
27 * ethernet-phy-idAAAA.BBBB */
of_get_phy_id(struct device_node * device,u32 * phy_id)28 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
29 {
30 struct property *prop;
31 const char *cp;
32 unsigned int upper, lower;
33
34 of_property_for_each_string(device, "compatible", prop, cp) {
35 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
36 *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
37 return 0;
38 }
39 }
40 return -EINVAL;
41 }
42
of_mdiobus_register_phy(struct mii_bus * mdio,struct device_node * child,u32 addr)43 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
44 u32 addr)
45 {
46 struct phy_device *phy;
47 bool is_c45;
48 int rc;
49 u32 phy_id;
50
51 is_c45 = of_device_is_compatible(child,
52 "ethernet-phy-ieee802.3-c45");
53
54 if (!is_c45 && !of_get_phy_id(child, &phy_id))
55 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
56 else
57 phy = get_phy_device(mdio, addr, is_c45);
58 if (!phy || IS_ERR(phy))
59 return 1;
60
61 rc = irq_of_parse_and_map(child, 0);
62 if (rc > 0) {
63 phy->irq = rc;
64 if (mdio->irq)
65 mdio->irq[addr] = rc;
66 } else {
67 if (mdio->irq)
68 phy->irq = mdio->irq[addr];
69 }
70
71 /* Associate the OF node with the device structure so it
72 * can be looked up later */
73 of_node_get(child);
74 phy->dev.of_node = child;
75
76 /* All data is now stored in the phy struct;
77 * register it */
78 rc = phy_device_register(phy);
79 if (rc) {
80 phy_device_free(phy);
81 of_node_put(child);
82 return 1;
83 }
84
85 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
86 child->name, addr);
87
88 return 0;
89 }
90
of_mdio_parse_addr(struct device * dev,const struct device_node * np)91 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
92 {
93 u32 addr;
94 int ret;
95
96 ret = of_property_read_u32(np, "reg", &addr);
97 if (ret < 0) {
98 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
99 return ret;
100 }
101
102 /* A PHY must have a reg property in the range [0-31] */
103 if (addr >= PHY_MAX_ADDR) {
104 dev_err(dev, "%s PHY address %i is too large\n",
105 np->full_name, addr);
106 return -EINVAL;
107 }
108
109 return addr;
110 }
111 EXPORT_SYMBOL(of_mdio_parse_addr);
112
113 /**
114 * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
115 * @mdio: pointer to mii_bus structure
116 * @np: pointer to device_node of MDIO bus.
117 *
118 * This function registers the mii_bus structure and registers a phy_device
119 * for each child node of @np.
120 */
of_mdiobus_register(struct mii_bus * mdio,struct device_node * np)121 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
122 {
123 struct device_node *child;
124 const __be32 *paddr;
125 bool scanphys = false;
126 int addr, rc, i;
127
128 /* Mask out all PHYs from auto probing. Instead the PHYs listed in
129 * the device tree are populated after the bus has been registered */
130 mdio->phy_mask = ~0;
131
132 /* Clear all the IRQ properties */
133 if (mdio->irq)
134 for (i=0; i<PHY_MAX_ADDR; i++)
135 mdio->irq[i] = PHY_POLL;
136
137 mdio->dev.of_node = np;
138
139 /* Register the MDIO bus */
140 rc = mdiobus_register(mdio);
141 if (rc)
142 return rc;
143
144 /* Loop over the child nodes and register a phy_device for each one */
145 for_each_available_child_of_node(np, child) {
146 addr = of_mdio_parse_addr(&mdio->dev, child);
147 if (addr < 0) {
148 scanphys = true;
149 continue;
150 }
151
152 rc = of_mdiobus_register_phy(mdio, child, addr);
153 if (rc)
154 continue;
155 }
156
157 if (!scanphys)
158 return 0;
159
160 /* auto scan for PHYs with empty reg property */
161 for_each_available_child_of_node(np, child) {
162 /* Skip PHYs with reg property set */
163 paddr = of_get_property(child, "reg", NULL);
164 if (paddr)
165 continue;
166
167 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
168 /* skip already registered PHYs */
169 if (mdio->phy_map[addr])
170 continue;
171
172 /* be noisy to encourage people to set reg property */
173 dev_info(&mdio->dev, "scan phy %s at address %i\n",
174 child->name, addr);
175
176 rc = of_mdiobus_register_phy(mdio, child, addr);
177 if (rc)
178 continue;
179 }
180 }
181
182 return 0;
183 }
184 EXPORT_SYMBOL(of_mdiobus_register);
185
186 /* Helper function for of_phy_find_device */
of_phy_match(struct device * dev,void * phy_np)187 static int of_phy_match(struct device *dev, void *phy_np)
188 {
189 return dev->of_node == phy_np;
190 }
191
192 /**
193 * of_phy_find_device - Give a PHY node, find the phy_device
194 * @phy_np: Pointer to the phy's device tree node
195 *
196 * Returns a pointer to the phy_device.
197 */
of_phy_find_device(struct device_node * phy_np)198 struct phy_device *of_phy_find_device(struct device_node *phy_np)
199 {
200 struct device *d;
201 if (!phy_np)
202 return NULL;
203
204 d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
205 return d ? to_phy_device(d) : NULL;
206 }
207 EXPORT_SYMBOL(of_phy_find_device);
208
209 /**
210 * of_phy_connect - Connect to the phy described in the device tree
211 * @dev: pointer to net_device claiming the phy
212 * @phy_np: Pointer to device tree node for the PHY
213 * @hndlr: Link state callback for the network device
214 * @iface: PHY data interface type
215 *
216 * Returns a pointer to the phy_device if successful. NULL otherwise
217 */
of_phy_connect(struct net_device * dev,struct device_node * phy_np,void (* hndlr)(struct net_device *),u32 flags,phy_interface_t iface)218 struct phy_device *of_phy_connect(struct net_device *dev,
219 struct device_node *phy_np,
220 void (*hndlr)(struct net_device *), u32 flags,
221 phy_interface_t iface)
222 {
223 struct phy_device *phy = of_phy_find_device(phy_np);
224
225 if (!phy)
226 return NULL;
227
228 phy->dev_flags = flags;
229
230 return phy_connect_direct(dev, phy, hndlr, iface) ? NULL : phy;
231 }
232 EXPORT_SYMBOL(of_phy_connect);
233
234 /**
235 * of_phy_attach - Attach to a PHY without starting the state machine
236 * @dev: pointer to net_device claiming the phy
237 * @phy_np: Node pointer for the PHY
238 * @flags: flags to pass to the PHY
239 * @iface: PHY data interface type
240 */
of_phy_attach(struct net_device * dev,struct device_node * phy_np,u32 flags,phy_interface_t iface)241 struct phy_device *of_phy_attach(struct net_device *dev,
242 struct device_node *phy_np, u32 flags,
243 phy_interface_t iface)
244 {
245 struct phy_device *phy = of_phy_find_device(phy_np);
246
247 if (!phy)
248 return NULL;
249
250 return phy_attach_direct(dev, phy, flags, iface) ? NULL : phy;
251 }
252 EXPORT_SYMBOL(of_phy_attach);
253
254 #if defined(CONFIG_FIXED_PHY)
255 /*
256 * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
257 * support two DT bindings:
258 * - the old DT binding, where 'fixed-link' was a property with 5
259 * cells encoding various informations about the fixed PHY
260 * - the new DT binding, where 'fixed-link' is a sub-node of the
261 * Ethernet device.
262 */
of_phy_is_fixed_link(struct device_node * np)263 bool of_phy_is_fixed_link(struct device_node *np)
264 {
265 struct device_node *dn;
266 int len, err;
267 const char *managed;
268
269 /* New binding */
270 dn = of_get_child_by_name(np, "fixed-link");
271 if (dn) {
272 of_node_put(dn);
273 return true;
274 }
275
276 err = of_property_read_string(np, "managed", &managed);
277 if (err == 0 && strcmp(managed, "auto") != 0)
278 return true;
279
280 /* Old binding */
281 if (of_get_property(np, "fixed-link", &len) &&
282 len == (5 * sizeof(__be32)))
283 return true;
284
285 return false;
286 }
287 EXPORT_SYMBOL(of_phy_is_fixed_link);
288
of_phy_register_fixed_link(struct device_node * np)289 int of_phy_register_fixed_link(struct device_node *np)
290 {
291 struct fixed_phy_status status = {};
292 struct device_node *fixed_link_node;
293 const __be32 *fixed_link_prop;
294 int len, err;
295 struct phy_device *phy;
296 const char *managed;
297
298 err = of_property_read_string(np, "managed", &managed);
299 if (err == 0) {
300 if (strcmp(managed, "in-band-status") == 0) {
301 /* status is zeroed, namely its .link member */
302 phy = fixed_phy_register(PHY_POLL, &status, np);
303 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
304 }
305 }
306
307 /* New binding */
308 fixed_link_node = of_get_child_by_name(np, "fixed-link");
309 if (fixed_link_node) {
310 status.link = 1;
311 status.duplex = of_property_read_bool(fixed_link_node,
312 "full-duplex");
313 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
314 return -EINVAL;
315 status.pause = of_property_read_bool(fixed_link_node, "pause");
316 status.asym_pause = of_property_read_bool(fixed_link_node,
317 "asym-pause");
318 of_node_put(fixed_link_node);
319 phy = fixed_phy_register(PHY_POLL, &status, np);
320 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
321 }
322
323 /* Old binding */
324 fixed_link_prop = of_get_property(np, "fixed-link", &len);
325 if (fixed_link_prop && len == (5 * sizeof(__be32))) {
326 status.link = 1;
327 status.duplex = be32_to_cpu(fixed_link_prop[1]);
328 status.speed = be32_to_cpu(fixed_link_prop[2]);
329 status.pause = be32_to_cpu(fixed_link_prop[3]);
330 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
331 phy = fixed_phy_register(PHY_POLL, &status, np);
332 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
333 }
334
335 return -ENODEV;
336 }
337 EXPORT_SYMBOL(of_phy_register_fixed_link);
338 #endif
339