1 // SPDX-License-Identifier: GPL-2.0-only
3 * OF helpers for the MDIO (Ethernet PHY) API
5 * Copyright (c) 2009 Secret Lab Technologies, Ltd.
7 * This file provides helper functions for extracting PHY device information
8 * out of the OpenFirmware device tree and using it to populate an mii_bus.
11 #include <linux/kernel.h>
12 #include <linux/device.h>
13 #include <linux/netdevice.h>
14 #include <linux/err.h>
15 #include <linux/phy.h>
16 #include <linux/phy_fixed.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_mdio.h>
20 #include <linux/of_net.h>
21 #include <linux/module.h>
23 #define DEFAULT_GPIO_RESET_DELAY 10 /* in microseconds */
25 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
26 MODULE_LICENSE("GPL");
28 /* Extract the clause 22 phy ID from the compatible string of the form
29 * ethernet-phy-idAAAA.BBBB */
30 static int of_get_phy_id(struct device_node *device, u32 *phy_id)
32 struct property *prop;
34 unsigned int upper, lower;
36 of_property_for_each_string(device, "compatible", prop, cp) {
37 if (sscanf(cp, "ethernet-phy-id%4x.%4x", &upper, &lower) == 2) {
38 *phy_id = ((upper & 0xFFFF) << 16) | (lower & 0xFFFF);
45 static struct mii_timestamper *of_find_mii_timestamper(struct device_node *node)
47 struct of_phandle_args arg;
50 err = of_parse_phandle_with_fixed_args(node, "timestamper", 1, 0, &arg);
57 if (arg.args_count != 1)
58 return ERR_PTR(-EINVAL);
60 return register_mii_timestamper(arg.np, arg.args[0]);
63 int of_mdiobus_phy_device_register(struct mii_bus *mdio, struct phy_device *phy,
64 struct device_node *child, u32 addr)
68 rc = of_irq_get(child, 0);
69 if (rc == -EPROBE_DEFER)
76 phy->irq = mdio->irq[addr];
79 if (of_property_read_bool(child, "broken-turn-around"))
80 mdio->phy_ignore_ta_mask |= 1 << addr;
82 of_property_read_u32(child, "reset-assert-us",
83 &phy->mdio.reset_assert_delay);
84 of_property_read_u32(child, "reset-deassert-us",
85 &phy->mdio.reset_deassert_delay);
87 /* Associate the OF node with the device structure so it
88 * can be looked up later */
90 phy->mdio.dev.of_node = child;
91 phy->mdio.dev.fwnode = of_fwnode_handle(child);
93 /* All data is now stored in the phy struct;
95 rc = phy_device_register(phy);
101 dev_dbg(&mdio->dev, "registered phy %pOFn at address %i\n",
105 EXPORT_SYMBOL(of_mdiobus_phy_device_register);
107 static int of_mdiobus_register_phy(struct mii_bus *mdio,
108 struct device_node *child, u32 addr)
110 struct mii_timestamper *mii_ts;
111 struct phy_device *phy;
116 mii_ts = of_find_mii_timestamper(child);
118 return PTR_ERR(mii_ts);
120 is_c45 = of_device_is_compatible(child,
121 "ethernet-phy-ieee802.3-c45");
123 if (!is_c45 && !of_get_phy_id(child, &phy_id))
124 phy = phy_device_create(mdio, addr, phy_id, 0, NULL);
126 phy = get_phy_device(mdio, addr, is_c45);
129 unregister_mii_timestamper(mii_ts);
133 rc = of_mdiobus_phy_device_register(mdio, phy, child, addr);
136 unregister_mii_timestamper(mii_ts);
137 phy_device_free(phy);
141 /* phy->mii_ts may already be defined by the PHY driver. A
142 * mii_timestamper probed via the device tree will still have
146 phy->mii_ts = mii_ts;
151 static int of_mdiobus_register_device(struct mii_bus *mdio,
152 struct device_node *child, u32 addr)
154 struct mdio_device *mdiodev;
157 mdiodev = mdio_device_create(mdio, addr);
159 return PTR_ERR(mdiodev);
161 /* Associate the OF node with the device structure so it
162 * can be looked up later.
165 mdiodev->dev.of_node = child;
166 mdiodev->dev.fwnode = of_fwnode_handle(child);
168 /* All data is now stored in the mdiodev struct; register it. */
169 rc = mdio_device_register(mdiodev);
171 mdio_device_free(mdiodev);
176 dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n",
181 /* The following is a list of PHY compatible strings which appear in
182 * some DTBs. The compatible string is never matched against a PHY
183 * driver, so is pointless. We only expect devices which are not PHYs
184 * to have a compatible string, so they can be matched to an MDIO
185 * driver. Encourage users to upgrade their DT blobs to remove these.
187 static const struct of_device_id whitelist_phys[] = {
188 { .compatible = "brcm,40nm-ephy" },
189 { .compatible = "broadcom,bcm5241" },
190 { .compatible = "marvell,88E1111", },
191 { .compatible = "marvell,88e1116", },
192 { .compatible = "marvell,88e1118", },
193 { .compatible = "marvell,88e1145", },
194 { .compatible = "marvell,88e1149r", },
195 { .compatible = "marvell,88e1310", },
196 { .compatible = "marvell,88E1510", },
197 { .compatible = "marvell,88E1514", },
198 { .compatible = "moxa,moxart-rtl8201cp", },
203 * Return true if the child node is for a phy. It must either:
204 * o Compatible string of "ethernet-phy-idX.X"
205 * o Compatible string of "ethernet-phy-ieee802.3-c45"
206 * o Compatible string of "ethernet-phy-ieee802.3-c22"
207 * o In the white list above (and issue a warning)
208 * o No compatibility string
210 * A device which is not a phy is expected to have a compatible string
211 * indicating what sort of device it is.
213 bool of_mdiobus_child_is_phy(struct device_node *child)
217 if (of_get_phy_id(child, &phy_id) != -EINVAL)
220 if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
223 if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
226 if (of_match_node(whitelist_phys, child)) {
228 "%pOF: Whitelisted compatible string. Please remove\n",
233 if (!of_find_property(child, "compatible", NULL))
238 EXPORT_SYMBOL(of_mdiobus_child_is_phy);
241 * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
242 * @mdio: pointer to mii_bus structure
243 * @np: pointer to device_node of MDIO bus.
245 * This function registers the mii_bus structure and registers a phy_device
246 * for each child node of @np.
248 int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
250 struct device_node *child;
251 bool scanphys = false;
255 return mdiobus_register(mdio);
257 /* Do not continue if the node is disabled */
258 if (!of_device_is_available(np))
261 /* Mask out all PHYs from auto probing. Instead the PHYs listed in
262 * the device tree are populated after the bus has been registered */
265 mdio->dev.of_node = np;
266 mdio->dev.fwnode = of_fwnode_handle(np);
268 /* Get bus level PHY reset GPIO details */
269 mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY;
270 of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us);
272 /* Register the MDIO bus */
273 rc = mdiobus_register(mdio);
277 /* Loop over the child nodes and register a phy_device for each phy */
278 for_each_available_child_of_node(np, child) {
279 addr = of_mdio_parse_addr(&mdio->dev, child);
285 if (of_mdiobus_child_is_phy(child))
286 rc = of_mdiobus_register_phy(mdio, child, addr);
288 rc = of_mdiobus_register_device(mdio, child, addr);
292 "MDIO device at address %d is missing.\n",
301 /* auto scan for PHYs with empty reg property */
302 for_each_available_child_of_node(np, child) {
303 /* Skip PHYs with reg property set */
304 if (of_find_property(child, "reg", NULL))
307 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
308 /* skip already registered PHYs */
309 if (mdiobus_is_registered_device(mdio, addr))
312 /* be noisy to encourage people to set reg property */
313 dev_info(&mdio->dev, "scan phy %pOFn at address %i\n",
316 if (of_mdiobus_child_is_phy(child)) {
317 /* -ENODEV is the return code that PHYLIB has
318 * standardized on to indicate that bus
319 * scanning should continue.
321 rc = of_mdiobus_register_phy(mdio, child, addr);
333 mdiobus_unregister(mdio);
336 EXPORT_SYMBOL(of_mdiobus_register);
339 * of_phy_find_device - Give a PHY node, find the phy_device
340 * @phy_np: Pointer to the phy's device tree node
342 * If successful, returns a pointer to the phy_device with the embedded
343 * struct device refcount incremented by one, or NULL on failure.
345 struct phy_device *of_phy_find_device(struct device_node *phy_np)
348 struct mdio_device *mdiodev;
353 d = bus_find_device_by_of_node(&mdio_bus_type, phy_np);
355 mdiodev = to_mdio_device(d);
356 if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY)
357 return to_phy_device(d);
363 EXPORT_SYMBOL(of_phy_find_device);
366 * of_phy_connect - Connect to the phy described in the device tree
367 * @dev: pointer to net_device claiming the phy
368 * @phy_np: Pointer to device tree node for the PHY
369 * @hndlr: Link state callback for the network device
370 * @flags: flags to pass to the PHY
371 * @iface: PHY data interface type
373 * If successful, returns a pointer to the phy_device with the embedded
374 * struct device refcount incremented by one, or NULL on failure. The
375 * refcount must be dropped by calling phy_disconnect() or phy_detach().
377 struct phy_device *of_phy_connect(struct net_device *dev,
378 struct device_node *phy_np,
379 void (*hndlr)(struct net_device *), u32 flags,
380 phy_interface_t iface)
382 struct phy_device *phy = of_phy_find_device(phy_np);
388 phy->dev_flags = flags;
390 ret = phy_connect_direct(dev, phy, hndlr, iface);
392 /* refcount is held by phy_connect_direct() on success */
393 put_device(&phy->mdio.dev);
395 return ret ? NULL : phy;
397 EXPORT_SYMBOL(of_phy_connect);
400 * of_phy_get_and_connect
401 * - Get phy node and connect to the phy described in the device tree
402 * @dev: pointer to net_device claiming the phy
403 * @np: Pointer to device tree node for the net_device claiming the phy
404 * @hndlr: Link state callback for the network device
406 * If successful, returns a pointer to the phy_device with the embedded
407 * struct device refcount incremented by one, or NULL on failure. The
408 * refcount must be dropped by calling phy_disconnect() or phy_detach().
410 struct phy_device *of_phy_get_and_connect(struct net_device *dev,
411 struct device_node *np,
412 void (*hndlr)(struct net_device *))
414 phy_interface_t iface;
415 struct device_node *phy_np;
416 struct phy_device *phy;
419 ret = of_get_phy_mode(np, &iface);
422 if (of_phy_is_fixed_link(np)) {
423 ret = of_phy_register_fixed_link(np);
425 netdev_err(dev, "broken fixed-link specification\n");
428 phy_np = of_node_get(np);
430 phy_np = of_parse_phandle(np, "phy-handle", 0);
435 phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
441 EXPORT_SYMBOL(of_phy_get_and_connect);
444 * of_phy_attach - Attach to a PHY without starting the state machine
445 * @dev: pointer to net_device claiming the phy
446 * @phy_np: Node pointer for the PHY
447 * @flags: flags to pass to the PHY
448 * @iface: PHY data interface type
450 * If successful, returns a pointer to the phy_device with the embedded
451 * struct device refcount incremented by one, or NULL on failure. The
452 * refcount must be dropped by calling phy_disconnect() or phy_detach().
454 struct phy_device *of_phy_attach(struct net_device *dev,
455 struct device_node *phy_np, u32 flags,
456 phy_interface_t iface)
458 struct phy_device *phy = of_phy_find_device(phy_np);
464 ret = phy_attach_direct(dev, phy, flags, iface);
466 /* refcount is held by phy_attach_direct() on success */
467 put_device(&phy->mdio.dev);
469 return ret ? NULL : phy;
471 EXPORT_SYMBOL(of_phy_attach);
474 * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
475 * support two DT bindings:
476 * - the old DT binding, where 'fixed-link' was a property with 5
477 * cells encoding various informations about the fixed PHY
478 * - the new DT binding, where 'fixed-link' is a sub-node of the
481 bool of_phy_is_fixed_link(struct device_node *np)
483 struct device_node *dn;
488 dn = of_get_child_by_name(np, "fixed-link");
494 err = of_property_read_string(np, "managed", &managed);
495 if (err == 0 && strcmp(managed, "auto") != 0)
499 if (of_get_property(np, "fixed-link", &len) &&
500 len == (5 * sizeof(__be32)))
505 EXPORT_SYMBOL(of_phy_is_fixed_link);
507 int of_phy_register_fixed_link(struct device_node *np)
509 struct fixed_phy_status status = {};
510 struct device_node *fixed_link_node;
511 u32 fixed_link_prop[5];
514 if (of_property_read_string(np, "managed", &managed) == 0 &&
515 strcmp(managed, "in-band-status") == 0) {
516 /* status is zeroed, namely its .link member */
521 fixed_link_node = of_get_child_by_name(np, "fixed-link");
522 if (fixed_link_node) {
524 status.duplex = of_property_read_bool(fixed_link_node,
526 if (of_property_read_u32(fixed_link_node, "speed",
528 of_node_put(fixed_link_node);
531 status.pause = of_property_read_bool(fixed_link_node, "pause");
532 status.asym_pause = of_property_read_bool(fixed_link_node,
534 of_node_put(fixed_link_node);
540 if (of_property_read_u32_array(np, "fixed-link", fixed_link_prop,
541 ARRAY_SIZE(fixed_link_prop)) == 0) {
543 status.duplex = fixed_link_prop[1];
544 status.speed = fixed_link_prop[2];
545 status.pause = fixed_link_prop[3];
546 status.asym_pause = fixed_link_prop[4];
553 return PTR_ERR_OR_ZERO(fixed_phy_register(PHY_POLL, &status, np));
555 EXPORT_SYMBOL(of_phy_register_fixed_link);
557 void of_phy_deregister_fixed_link(struct device_node *np)
559 struct phy_device *phydev;
561 phydev = of_phy_find_device(np);
565 fixed_phy_unregister(phydev);
567 put_device(&phydev->mdio.dev); /* of_phy_find_device() */
568 phy_device_free(phydev); /* fixed_phy_register() */
570 EXPORT_SYMBOL(of_phy_deregister_fixed_link);