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