2 * OF helpers for the MDIO (Ethernet PHY) API
4 * Copyright (c) 2009 Secret Lab Technologies, Ltd.
6 * This file is released under the GPLv2
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.
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>
19 #include <linux/of_gpio.h>
20 #include <linux/of_irq.h>
21 #include <linux/of_mdio.h>
22 #include <linux/module.h>
24 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
25 MODULE_LICENSE("GPL");
27 /* Extract the clause 22 phy ID from the compatible string of the form
28 * ethernet-phy-idAAAA.BBBB */
29 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
31 struct property *prop;
33 unsigned int upper, lower;
35 of_property_for_each_string(device, "compatible", prop, cp) {
36 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
37 *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
44 static int of_mdiobus_register_phy(struct mii_bus *mdio, struct device_node *child,
47 struct phy_device *phy;
52 is_c45 = of_device_is_compatible(child,
53 "ethernet-phy-ieee802.3-c45");
55 if (!is_c45 && !of_get_phy_id(child, &phy_id))
56 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
58 phy = get_phy_device(mdio, addr, is_c45);
59 if (!phy || IS_ERR(phy))
62 rc = irq_of_parse_and_map(child, 0);
69 phy->irq = mdio->irq[addr];
72 if (of_property_read_bool(child, "broken-turn-around"))
73 mdio->phy_ignore_ta_mask |= 1 << addr;
75 /* Associate the OF node with the device structure so it
76 * can be looked up later */
78 phy->mdio.dev.of_node = child;
80 /* All data is now stored in the phy struct;
82 rc = phy_device_register(phy);
89 dev_dbg(&mdio->dev, "registered phy %s at address %i\n",
95 int of_mdio_parse_addr(struct device *dev, const struct device_node *np)
100 ret = of_property_read_u32(np, "reg", &addr);
102 dev_err(dev, "%s has invalid PHY address\n", np->full_name);
106 /* A PHY must have a reg property in the range [0-31] */
107 if (addr >= PHY_MAX_ADDR) {
108 dev_err(dev, "%s PHY address %i is too large\n",
109 np->full_name, addr);
115 EXPORT_SYMBOL(of_mdio_parse_addr);
118 * Return true if the child node is for a phy. It must either:
119 * o Compatible string of "ethernet-phy-idX.X"
120 * o Compatible string of "ethernet-phy-ieee802.3-c45"
121 * o Compatible string of "ethernet-phy-ieee802.3-c22"
122 * o No compatibility string
124 * A device which is not a phy is expected to have a compatible string
125 * indicating what sort of device it is.
127 static bool of_mdiobus_child_is_phy(struct device_node *child)
131 if (of_get_phy_id(child, &phy_id) != -EINVAL)
134 if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
137 if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
140 if (!of_find_property(child, "compatible", NULL))
147 * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
148 * @mdio: pointer to mii_bus structure
149 * @np: pointer to device_node of MDIO bus.
151 * This function registers the mii_bus structure and registers a phy_device
152 * for each child node of @np.
154 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
156 struct device_node *child;
158 bool scanphys = false;
161 /* Mask out all PHYs from auto probing. Instead the PHYs listed in
162 * the device tree are populated after the bus has been registered */
165 mdio->dev.of_node = np;
167 /* Register the MDIO bus */
168 rc = mdiobus_register(mdio);
172 /* Loop over the child nodes and register a phy_device for each phy */
173 for_each_available_child_of_node(np, child) {
174 addr = of_mdio_parse_addr(&mdio->dev, child);
180 if (of_mdiobus_child_is_phy(child))
181 of_mdiobus_register_phy(mdio, child, addr);
187 /* auto scan for PHYs with empty reg property */
188 for_each_available_child_of_node(np, child) {
189 /* Skip PHYs with reg property set */
190 paddr = of_get_property(child, "reg", NULL);
194 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
195 /* skip already registered PHYs */
196 if (mdio->phy_map[addr])
199 /* be noisy to encourage people to set reg property */
200 dev_info(&mdio->dev, "scan phy %s at address %i\n",
203 if (of_mdiobus_child_is_phy(child))
204 of_mdiobus_register_phy(mdio, child, addr);
210 EXPORT_SYMBOL(of_mdiobus_register);
212 /* Helper function for of_phy_find_device */
213 static int of_phy_match(struct device *dev, void *phy_np)
215 return dev->of_node == phy_np;
219 * of_phy_find_device - Give a PHY node, find the phy_device
220 * @phy_np: Pointer to the phy's device tree node
222 * If successful, returns a pointer to the phy_device with the embedded
223 * struct device refcount incremented by one, or NULL on failure.
225 struct phy_device *of_phy_find_device(struct device_node *phy_np)
231 d = bus_find_device(&mdio_bus_type, NULL, phy_np, of_phy_match);
232 return d ? to_phy_device(d) : NULL;
234 EXPORT_SYMBOL(of_phy_find_device);
237 * of_phy_connect - Connect to the phy described in the device tree
238 * @dev: pointer to net_device claiming the phy
239 * @phy_np: Pointer to device tree node for the PHY
240 * @hndlr: Link state callback for the network device
241 * @iface: PHY data interface type
243 * If successful, returns a pointer to the phy_device with the embedded
244 * struct device refcount incremented by one, or NULL on failure. The
245 * refcount must be dropped by calling phy_disconnect() or phy_detach().
247 struct phy_device *of_phy_connect(struct net_device *dev,
248 struct device_node *phy_np,
249 void (*hndlr)(struct net_device *), u32 flags,
250 phy_interface_t iface)
252 struct phy_device *phy = of_phy_find_device(phy_np);
258 phy->dev_flags = flags;
260 ret = phy_connect_direct(dev, phy, hndlr, iface);
262 /* refcount is held by phy_connect_direct() on success */
263 put_device(&phy->mdio.dev);
265 return ret ? NULL : phy;
267 EXPORT_SYMBOL(of_phy_connect);
270 * of_phy_attach - Attach to a PHY without starting the state machine
271 * @dev: pointer to net_device claiming the phy
272 * @phy_np: Node pointer for the PHY
273 * @flags: flags to pass to the PHY
274 * @iface: PHY data interface type
276 * If successful, returns a pointer to the phy_device with the embedded
277 * struct device refcount incremented by one, or NULL on failure. The
278 * refcount must be dropped by calling phy_disconnect() or phy_detach().
280 struct phy_device *of_phy_attach(struct net_device *dev,
281 struct device_node *phy_np, u32 flags,
282 phy_interface_t iface)
284 struct phy_device *phy = of_phy_find_device(phy_np);
290 ret = phy_attach_direct(dev, phy, flags, iface);
292 /* refcount is held by phy_attach_direct() on success */
293 put_device(&phy->mdio.dev);
295 return ret ? NULL : phy;
297 EXPORT_SYMBOL(of_phy_attach);
299 #if defined(CONFIG_FIXED_PHY)
301 * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
302 * support two DT bindings:
303 * - the old DT binding, where 'fixed-link' was a property with 5
304 * cells encoding various informations about the fixed PHY
305 * - the new DT binding, where 'fixed-link' is a sub-node of the
308 bool of_phy_is_fixed_link(struct device_node *np)
310 struct device_node *dn;
315 dn = of_get_child_by_name(np, "fixed-link");
321 err = of_property_read_string(np, "managed", &managed);
322 if (err == 0 && strcmp(managed, "auto") != 0)
326 if (of_get_property(np, "fixed-link", &len) &&
327 len == (5 * sizeof(__be32)))
332 EXPORT_SYMBOL(of_phy_is_fixed_link);
334 int of_phy_register_fixed_link(struct device_node *np)
336 struct fixed_phy_status status = {};
337 struct device_node *fixed_link_node;
338 const __be32 *fixed_link_prop;
341 struct phy_device *phy;
344 err = of_property_read_string(np, "managed", &managed);
346 if (strcmp(managed, "in-band-status") == 0) {
347 /* status is zeroed, namely its .link member */
348 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
349 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
354 fixed_link_node = of_get_child_by_name(np, "fixed-link");
355 if (fixed_link_node) {
357 status.duplex = of_property_read_bool(fixed_link_node,
359 if (of_property_read_u32(fixed_link_node, "speed", &status.speed))
361 status.pause = of_property_read_bool(fixed_link_node, "pause");
362 status.asym_pause = of_property_read_bool(fixed_link_node,
364 link_gpio = of_get_named_gpio_flags(fixed_link_node,
365 "link-gpios", 0, NULL);
366 of_node_put(fixed_link_node);
367 if (link_gpio == -EPROBE_DEFER)
368 return -EPROBE_DEFER;
370 phy = fixed_phy_register(PHY_POLL, &status, link_gpio, np);
371 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
375 fixed_link_prop = of_get_property(np, "fixed-link", &len);
376 if (fixed_link_prop && len == (5 * sizeof(__be32))) {
378 status.duplex = be32_to_cpu(fixed_link_prop[1]);
379 status.speed = be32_to_cpu(fixed_link_prop[2]);
380 status.pause = be32_to_cpu(fixed_link_prop[3]);
381 status.asym_pause = be32_to_cpu(fixed_link_prop[4]);
382 phy = fixed_phy_register(PHY_POLL, &status, -1, np);
383 return IS_ERR(phy) ? PTR_ERR(phy) : 0;
388 EXPORT_SYMBOL(of_phy_register_fixed_link);