1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * OF helpers for the MDIO (Ethernet PHY) API
4 *
5 * Copyright (c) 2009 Secret Lab Technologies, Ltd.
6 *
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.
9 */
10
11#include <linux/device.h>
12#include <linux/err.h>
13#include <linux/fwnode_mdio.h>
14#include <linux/kernel.h>
15#include <linux/module.h>
16#include <linux/netdevice.h>
17#include <linux/of.h>
18#include <linux/of_irq.h>
19#include <linux/of_mdio.h>
20#include <linux/of_net.h>
21#include <linux/phy.h>
22#include <linux/phy_fixed.h>
23
24#define DEFAULT_GPIO_RESET_DELAY 10 /* in microseconds */
25
26MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
27MODULE_LICENSE("GPL");
28MODULE_DESCRIPTION("OpenFirmware MDIO bus (Ethernet PHY) accessors");
29
30/* Extract the clause 22 phy ID from the compatible string of the form
31 * ethernet-phy-idAAAA.BBBB */
32static int of_get_phy_id(struct device_node *device, u32 *phy_id)
33{
34 return fwnode_get_phy_id(of_fwnode_handle(device), phy_id);
35}
36
37int of_mdiobus_phy_device_register(struct mii_bus *mdio, struct phy_device *phy,
38 struct device_node *child, u32 addr)
39{
40 return fwnode_mdiobus_phy_device_register(mdio, phy,
41 of_fwnode_handle(child),
42 addr);
43}
44EXPORT_SYMBOL(of_mdiobus_phy_device_register);
45
46static int of_mdiobus_register_phy(struct mii_bus *mdio,
47 struct device_node *child, u32 addr)
48{
49 return fwnode_mdiobus_register_phy(bus: mdio, of_fwnode_handle(child), addr);
50}
51
52static int of_mdiobus_register_device(struct mii_bus *mdio,
53 struct device_node *child, u32 addr)
54{
55 struct fwnode_handle *fwnode = of_fwnode_handle(child);
56 struct mdio_device *mdiodev;
57 int rc;
58
59 mdiodev = mdio_device_create(bus: mdio, addr);
60 if (IS_ERR(ptr: mdiodev))
61 return PTR_ERR(ptr: mdiodev);
62
63 /* Associate the OF node with the device structure so it
64 * can be looked up later.
65 */
66 fwnode_handle_get(fwnode);
67 device_set_node(dev: &mdiodev->dev, fwnode);
68
69 /* All data is now stored in the mdiodev struct; register it. */
70 rc = mdio_device_register(mdiodev);
71 if (rc) {
72 device_set_node(dev: &mdiodev->dev, NULL);
73 fwnode_handle_put(fwnode);
74 mdio_device_free(mdiodev);
75 return rc;
76 }
77
78 dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n",
79 child, addr);
80 return 0;
81}
82
83/* The following is a list of PHY compatible strings which appear in
84 * some DTBs. The compatible string is never matched against a PHY
85 * driver, so is pointless. We only expect devices which are not PHYs
86 * to have a compatible string, so they can be matched to an MDIO
87 * driver. Encourage users to upgrade their DT blobs to remove these.
88 */
89static const struct of_device_id whitelist_phys[] = {
90 { .compatible = "brcm,40nm-ephy" },
91 { .compatible = "broadcom,bcm5241" },
92 { .compatible = "marvell,88E1111", },
93 { .compatible = "marvell,88e1116", },
94 { .compatible = "marvell,88e1118", },
95 { .compatible = "marvell,88e1145", },
96 { .compatible = "marvell,88e1149r", },
97 { .compatible = "marvell,88e1310", },
98 { .compatible = "marvell,88E1510", },
99 { .compatible = "marvell,88E1514", },
100 { .compatible = "moxa,moxart-rtl8201cp", },
101 {}
102};
103
104/*
105 * Return true if the child node is for a phy. It must either:
106 * o Compatible string of "ethernet-phy-idX.X"
107 * o Compatible string of "ethernet-phy-ieee802.3-c45"
108 * o Compatible string of "ethernet-phy-ieee802.3-c22"
109 * o In the white list above (and issue a warning)
110 * o No compatibility string
111 *
112 * A device which is not a phy is expected to have a compatible string
113 * indicating what sort of device it is.
114 */
115bool of_mdiobus_child_is_phy(struct device_node *child)
116{
117 u32 phy_id;
118
119 if (of_get_phy_id(device: child, phy_id: &phy_id) != -EINVAL)
120 return true;
121
122 if (of_device_is_compatible(device: child, "ethernet-phy-ieee802.3-c45"))
123 return true;
124
125 if (of_device_is_compatible(device: child, "ethernet-phy-ieee802.3-c22"))
126 return true;
127
128 if (of_match_node(matches: whitelist_phys, node: child)) {
129 pr_warn(FW_WARN
130 "%pOF: Whitelisted compatible string. Please remove\n",
131 child);
132 return true;
133 }
134
135 if (!of_property_present(np: child, propname: "compatible"))
136 return true;
137
138 return false;
139}
140EXPORT_SYMBOL(of_mdiobus_child_is_phy);
141
142static int __of_mdiobus_parse_phys(struct mii_bus *mdio, struct device_node *np,
143 bool *scanphys)
144{
145 struct device_node *child;
146 int addr, rc = 0;
147
148 /* Loop over the child nodes and register a phy_device for each phy */
149 for_each_available_child_of_node(np, child) {
150 if (of_node_name_eq(np: child, name: "ethernet-phy-package")) {
151 /* Ignore invalid ethernet-phy-package node */
152 if (!of_property_present(np: child, propname: "reg"))
153 continue;
154
155 rc = __of_mdiobus_parse_phys(mdio, np: child, NULL);
156 if (rc && rc != -ENODEV)
157 goto exit;
158
159 continue;
160 }
161
162 addr = of_mdio_parse_addr(dev: &mdio->dev, np: child);
163 if (addr < 0) {
164 /* Skip scanning for invalid ethernet-phy-package node */
165 if (scanphys)
166 *scanphys = true;
167 continue;
168 }
169
170 if (of_mdiobus_child_is_phy(child))
171 rc = of_mdiobus_register_phy(mdio, child, addr);
172 else
173 rc = of_mdiobus_register_device(mdio, child, addr);
174
175 if (rc == -ENODEV)
176 dev_err(&mdio->dev,
177 "MDIO device at address %d is missing.\n",
178 addr);
179 else if (rc)
180 goto exit;
181 }
182
183 return 0;
184exit:
185 of_node_put(node: child);
186 return rc;
187}
188
189/**
190 * __of_mdiobus_register - Register mii_bus and create PHYs from the device tree
191 * @mdio: pointer to mii_bus structure
192 * @np: pointer to device_node of MDIO bus.
193 * @owner: module owning the @mdio object.
194 *
195 * This function registers the mii_bus structure and registers a phy_device
196 * for each child node of @np.
197 */
198int __of_mdiobus_register(struct mii_bus *mdio, struct device_node *np,
199 struct module *owner)
200{
201 struct device_node *child;
202 bool scanphys = false;
203 int addr, rc;
204
205 if (!np)
206 return __mdiobus_register(bus: mdio, owner);
207
208 /* Do not continue if the node is disabled */
209 if (!of_device_is_available(device: np))
210 return -ENODEV;
211
212 /* Mask out all PHYs from auto probing. Instead the PHYs listed in
213 * the device tree are populated after the bus has been registered */
214 mdio->phy_mask = ~0;
215
216 device_set_node(dev: &mdio->dev, of_fwnode_handle(np));
217
218 /* Get bus level PHY reset GPIO details */
219 mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY;
220 of_property_read_u32(np, propname: "reset-delay-us", out_value: &mdio->reset_delay_us);
221 mdio->reset_post_delay_us = 0;
222 of_property_read_u32(np, propname: "reset-post-delay-us", out_value: &mdio->reset_post_delay_us);
223
224 /* Register the MDIO bus */
225 rc = __mdiobus_register(bus: mdio, owner);
226 if (rc)
227 return rc;
228
229 /* Loop over the child nodes and register a phy_device for each phy */
230 rc = __of_mdiobus_parse_phys(mdio, np, scanphys: &scanphys);
231 if (rc)
232 goto unregister;
233
234 if (!scanphys)
235 return 0;
236
237 /* auto scan for PHYs with empty reg property */
238 for_each_available_child_of_node(np, child) {
239 /* Skip PHYs with reg property set or ethernet-phy-package node */
240 if (of_property_present(np: child, propname: "reg") ||
241 of_node_name_eq(np: child, name: "ethernet-phy-package"))
242 continue;
243
244 for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
245 /* skip already registered PHYs */
246 if (mdiobus_is_registered_device(bus: mdio, addr))
247 continue;
248
249 /* be noisy to encourage people to set reg property */
250 dev_info(&mdio->dev, "scan phy %pOFn at address %i\n",
251 child, addr);
252
253 if (of_mdiobus_child_is_phy(child)) {
254 /* -ENODEV is the return code that PHYLIB has
255 * standardized on to indicate that bus
256 * scanning should continue.
257 */
258 rc = of_mdiobus_register_phy(mdio, child, addr);
259 if (!rc)
260 break;
261 if (rc != -ENODEV)
262 goto put_unregister;
263 }
264 }
265 }
266
267 return 0;
268
269put_unregister:
270 of_node_put(node: child);
271unregister:
272 mdiobus_unregister(bus: mdio);
273 return rc;
274}
275EXPORT_SYMBOL(__of_mdiobus_register);
276
277/**
278 * of_mdio_find_device - Given a device tree node, find the mdio_device
279 * @np: pointer to the mdio_device's device tree node
280 *
281 * If successful, returns a pointer to the mdio_device with the embedded
282 * struct device refcount incremented by one, or NULL on failure.
283 * The caller should call put_device() on the mdio_device after its use
284 */
285struct mdio_device *of_mdio_find_device(struct device_node *np)
286{
287 return fwnode_mdio_find_device(of_fwnode_handle(np));
288}
289EXPORT_SYMBOL(of_mdio_find_device);
290
291/**
292 * of_phy_find_device - Give a PHY node, find the phy_device
293 * @phy_np: Pointer to the phy's device tree node
294 *
295 * If successful, returns a pointer to the phy_device with the embedded
296 * struct device refcount incremented by one, or NULL on failure.
297 */
298struct phy_device *of_phy_find_device(struct device_node *phy_np)
299{
300 return fwnode_phy_find_device(of_fwnode_handle(phy_np));
301}
302EXPORT_SYMBOL(of_phy_find_device);
303
304/**
305 * of_phy_connect - Connect to the phy described in the device tree
306 * @dev: pointer to net_device claiming the phy
307 * @phy_np: Pointer to device tree node for the PHY
308 * @hndlr: Link state callback for the network device
309 * @flags: flags to pass to the PHY
310 * @iface: PHY data interface type
311 *
312 * If successful, returns a pointer to the phy_device with the embedded
313 * struct device refcount incremented by one, or NULL on failure. The
314 * refcount must be dropped by calling phy_disconnect() or phy_detach().
315 */
316struct phy_device *of_phy_connect(struct net_device *dev,
317 struct device_node *phy_np,
318 void (*hndlr)(struct net_device *), u32 flags,
319 phy_interface_t iface)
320{
321 struct phy_device *phy = of_phy_find_device(phy_np);
322 int ret;
323
324 if (!phy)
325 return NULL;
326
327 phy->dev_flags |= flags;
328
329 ret = phy_connect_direct(dev, phydev: phy, handler: hndlr, interface: iface);
330
331 /* refcount is held by phy_connect_direct() on success */
332 put_device(dev: &phy->mdio.dev);
333
334 return ret ? NULL : phy;
335}
336EXPORT_SYMBOL(of_phy_connect);
337
338/**
339 * of_phy_get_and_connect
340 * - Get phy node and connect to the phy described in the device tree
341 * @dev: pointer to net_device claiming the phy
342 * @np: Pointer to device tree node for the net_device claiming the phy
343 * @hndlr: Link state callback for the network device
344 *
345 * If successful, returns a pointer to the phy_device with the embedded
346 * struct device refcount incremented by one, or NULL on failure. The
347 * refcount must be dropped by calling phy_disconnect() or phy_detach().
348 */
349struct phy_device *of_phy_get_and_connect(struct net_device *dev,
350 struct device_node *np,
351 void (*hndlr)(struct net_device *))
352{
353 phy_interface_t iface;
354 struct device_node *phy_np;
355 struct phy_device *phy;
356 int ret;
357
358 ret = of_get_phy_mode(np, interface: &iface);
359 if (ret)
360 return NULL;
361 if (of_phy_is_fixed_link(np)) {
362 ret = of_phy_register_fixed_link(np);
363 if (ret < 0) {
364 netdev_err(dev, format: "broken fixed-link specification\n");
365 return NULL;
366 }
367 phy_np = of_node_get(node: np);
368 } else {
369 phy_np = of_parse_phandle(np, phandle_name: "phy-handle", index: 0);
370 if (!phy_np)
371 return NULL;
372 }
373
374 phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
375
376 of_node_put(node: phy_np);
377
378 return phy;
379}
380EXPORT_SYMBOL(of_phy_get_and_connect);
381
382/*
383 * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
384 * support two DT bindings:
385 * - the old DT binding, where 'fixed-link' was a property with 5
386 * cells encoding various information about the fixed PHY
387 * - the new DT binding, where 'fixed-link' is a sub-node of the
388 * Ethernet device.
389 */
390bool of_phy_is_fixed_link(struct device_node *np)
391{
392 struct device_node *dn;
393 int len, err;
394 const char *managed;
395
396 /* New binding */
397 dn = of_get_child_by_name(node: np, name: "fixed-link");
398 if (dn) {
399 of_node_put(node: dn);
400 return true;
401 }
402
403 err = of_property_read_string(np, propname: "managed", out_string: &managed);
404 if (err == 0 && strcmp(managed, "auto") != 0)
405 return true;
406
407 /* Old binding */
408 if (of_get_property(node: np, name: "fixed-link", lenp: &len) &&
409 len == (5 * sizeof(__be32)))
410 return true;
411
412 return false;
413}
414EXPORT_SYMBOL(of_phy_is_fixed_link);
415
416int of_phy_register_fixed_link(struct device_node *np)
417{
418 struct fixed_phy_status status = {};
419 struct device_node *fixed_link_node;
420 u32 fixed_link_prop[5];
421 const char *managed;
422
423 if (of_property_read_string(np, propname: "managed", out_string: &managed) == 0 &&
424 strcmp(managed, "in-band-status") == 0) {
425 /* status is zeroed, namely its .link member */
426 goto register_phy;
427 }
428
429 /* New binding */
430 fixed_link_node = of_get_child_by_name(node: np, name: "fixed-link");
431 if (fixed_link_node) {
432 status.link = 1;
433 status.duplex = of_property_read_bool(np: fixed_link_node,
434 propname: "full-duplex");
435 if (of_property_read_u32(np: fixed_link_node, propname: "speed",
436 out_value: &status.speed)) {
437 of_node_put(node: fixed_link_node);
438 return -EINVAL;
439 }
440 status.pause = of_property_read_bool(np: fixed_link_node, propname: "pause");
441 status.asym_pause = of_property_read_bool(np: fixed_link_node,
442 propname: "asym-pause");
443 of_node_put(node: fixed_link_node);
444
445 goto register_phy;
446 }
447
448 /* Old binding */
449 if (of_property_read_u32_array(np, propname: "fixed-link", out_values: fixed_link_prop,
450 ARRAY_SIZE(fixed_link_prop)) == 0) {
451 status.link = 1;
452 status.duplex = fixed_link_prop[1];
453 status.speed = fixed_link_prop[2];
454 status.pause = fixed_link_prop[3];
455 status.asym_pause = fixed_link_prop[4];
456 goto register_phy;
457 }
458
459 return -ENODEV;
460
461register_phy:
462 return PTR_ERR_OR_ZERO(ptr: fixed_phy_register(PHY_POLL, status: &status, np));
463}
464EXPORT_SYMBOL(of_phy_register_fixed_link);
465
466void of_phy_deregister_fixed_link(struct device_node *np)
467{
468 struct phy_device *phydev;
469
470 phydev = of_phy_find_device(np);
471 if (!phydev)
472 return;
473
474 fixed_phy_unregister(phydev);
475
476 put_device(dev: &phydev->mdio.dev); /* of_phy_find_device() */
477 phy_device_free(phydev); /* fixed_phy_register() */
478}
479EXPORT_SYMBOL(of_phy_deregister_fixed_link);
480

source code of linux/drivers/net/mdio/of_mdio.c