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Note: File does not exist in v4.17.
  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");
 28
 29/* Extract the clause 22 phy ID from the compatible string of the form
 30 * ethernet-phy-idAAAA.BBBB */
 31static 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
 36int 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}
 43EXPORT_SYMBOL(of_mdiobus_phy_device_register);
 44
 45static 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
 51static 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		mdio_device_free(mdiodev);
 72		of_node_put(child);
 73		return rc;
 74	}
 75
 76	dev_dbg(&mdio->dev, "registered mdio device %pOFn at address %i\n",
 77		child, addr);
 78	return 0;
 79}
 80
 81/* The following is a list of PHY compatible strings which appear in
 82 * some DTBs. The compatible string is never matched against a PHY
 83 * driver, so is pointless. We only expect devices which are not PHYs
 84 * to have a compatible string, so they can be matched to an MDIO
 85 * driver.  Encourage users to upgrade their DT blobs to remove these.
 86 */
 87static const struct of_device_id whitelist_phys[] = {
 88	{ .compatible = "brcm,40nm-ephy" },
 89	{ .compatible = "broadcom,bcm5241" },
 90	{ .compatible = "marvell,88E1111", },
 91	{ .compatible = "marvell,88e1116", },
 92	{ .compatible = "marvell,88e1118", },
 93	{ .compatible = "marvell,88e1145", },
 94	{ .compatible = "marvell,88e1149r", },
 95	{ .compatible = "marvell,88e1310", },
 96	{ .compatible = "marvell,88E1510", },
 97	{ .compatible = "marvell,88E1514", },
 98	{ .compatible = "moxa,moxart-rtl8201cp", },
 99	{}
100};
101
102/*
103 * Return true if the child node is for a phy. It must either:
104 * o Compatible string of "ethernet-phy-idX.X"
105 * o Compatible string of "ethernet-phy-ieee802.3-c45"
106 * o Compatible string of "ethernet-phy-ieee802.3-c22"
107 * o In the white list above (and issue a warning)
108 * o No compatibility string
109 *
110 * A device which is not a phy is expected to have a compatible string
111 * indicating what sort of device it is.
112 */
113bool of_mdiobus_child_is_phy(struct device_node *child)
114{
115	u32 phy_id;
116
117	if (of_get_phy_id(child, &phy_id) != -EINVAL)
118		return true;
119
120	if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c45"))
121		return true;
122
123	if (of_device_is_compatible(child, "ethernet-phy-ieee802.3-c22"))
124		return true;
125
126	if (of_match_node(whitelist_phys, child)) {
127		pr_warn(FW_WARN
128			"%pOF: Whitelisted compatible string. Please remove\n",
129			child);
130		return true;
131	}
132
133	if (!of_find_property(child, "compatible", NULL))
134		return true;
135
136	return false;
137}
138EXPORT_SYMBOL(of_mdiobus_child_is_phy);
139
140/**
141 * of_mdiobus_register - Register mii_bus and create PHYs from the device tree
142 * @mdio: pointer to mii_bus structure
143 * @np: pointer to device_node of MDIO bus.
144 *
145 * This function registers the mii_bus structure and registers a phy_device
146 * for each child node of @np.
147 */
148int of_mdiobus_register(struct mii_bus *mdio, struct device_node *np)
149{
150	struct device_node *child;
151	bool scanphys = false;
152	int addr, rc;
153
154	if (!np)
155		return mdiobus_register(mdio);
156
157	/* Do not continue if the node is disabled */
158	if (!of_device_is_available(np))
159		return -ENODEV;
160
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 */
163	mdio->phy_mask = ~0;
164
165	device_set_node(&mdio->dev, of_fwnode_handle(np));
166
167	/* Get bus level PHY reset GPIO details */
168	mdio->reset_delay_us = DEFAULT_GPIO_RESET_DELAY;
169	of_property_read_u32(np, "reset-delay-us", &mdio->reset_delay_us);
170	mdio->reset_post_delay_us = 0;
171	of_property_read_u32(np, "reset-post-delay-us", &mdio->reset_post_delay_us);
172
173	/* Register the MDIO bus */
174	rc = mdiobus_register(mdio);
175	if (rc)
176		return rc;
177
178	/* Loop over the child nodes and register a phy_device for each phy */
179	for_each_available_child_of_node(np, child) {
180		addr = of_mdio_parse_addr(&mdio->dev, child);
181		if (addr < 0) {
182			scanphys = true;
183			continue;
184		}
185
186		if (of_mdiobus_child_is_phy(child))
187			rc = of_mdiobus_register_phy(mdio, child, addr);
188		else
189			rc = of_mdiobus_register_device(mdio, child, addr);
190
191		if (rc == -ENODEV)
192			dev_err(&mdio->dev,
193				"MDIO device at address %d is missing.\n",
194				addr);
195		else if (rc)
196			goto unregister;
197	}
198
199	if (!scanphys)
200		return 0;
201
202	/* auto scan for PHYs with empty reg property */
203	for_each_available_child_of_node(np, child) {
204		/* Skip PHYs with reg property set */
205		if (of_find_property(child, "reg", NULL))
206			continue;
207
208		for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
209			/* skip already registered PHYs */
210			if (mdiobus_is_registered_device(mdio, addr))
211				continue;
212
213			/* be noisy to encourage people to set reg property */
214			dev_info(&mdio->dev, "scan phy %pOFn at address %i\n",
215				 child, addr);
216
217			if (of_mdiobus_child_is_phy(child)) {
218				/* -ENODEV is the return code that PHYLIB has
219				 * standardized on to indicate that bus
220				 * scanning should continue.
221				 */
222				rc = of_mdiobus_register_phy(mdio, child, addr);
223				if (!rc)
224					break;
225				if (rc != -ENODEV)
226					goto unregister;
227			}
228		}
229	}
230
231	return 0;
232
233unregister:
234	mdiobus_unregister(mdio);
235	return rc;
236}
237EXPORT_SYMBOL(of_mdiobus_register);
238
239/**
240 * of_mdio_find_device - Given a device tree node, find the mdio_device
241 * @np: pointer to the mdio_device's device tree node
242 *
243 * If successful, returns a pointer to the mdio_device with the embedded
244 * struct device refcount incremented by one, or NULL on failure.
245 * The caller should call put_device() on the mdio_device after its use
246 */
247struct mdio_device *of_mdio_find_device(struct device_node *np)
248{
249	return fwnode_mdio_find_device(of_fwnode_handle(np));
250}
251EXPORT_SYMBOL(of_mdio_find_device);
252
253/**
254 * of_phy_find_device - Give a PHY node, find the phy_device
255 * @phy_np: Pointer to the phy's device tree node
256 *
257 * If successful, returns a pointer to the phy_device with the embedded
258 * struct device refcount incremented by one, or NULL on failure.
259 */
260struct phy_device *of_phy_find_device(struct device_node *phy_np)
261{
262	return fwnode_phy_find_device(of_fwnode_handle(phy_np));
263}
264EXPORT_SYMBOL(of_phy_find_device);
265
266/**
267 * of_phy_connect - Connect to the phy described in the device tree
268 * @dev: pointer to net_device claiming the phy
269 * @phy_np: Pointer to device tree node for the PHY
270 * @hndlr: Link state callback for the network device
271 * @flags: flags to pass to the PHY
272 * @iface: PHY data interface type
273 *
274 * If successful, returns a pointer to the phy_device with the embedded
275 * struct device refcount incremented by one, or NULL on failure. The
276 * refcount must be dropped by calling phy_disconnect() or phy_detach().
277 */
278struct phy_device *of_phy_connect(struct net_device *dev,
279				  struct device_node *phy_np,
280				  void (*hndlr)(struct net_device *), u32 flags,
281				  phy_interface_t iface)
282{
283	struct phy_device *phy = of_phy_find_device(phy_np);
284	int ret;
285
286	if (!phy)
287		return NULL;
288
289	phy->dev_flags |= flags;
290
291	ret = phy_connect_direct(dev, phy, hndlr, iface);
292
293	/* refcount is held by phy_connect_direct() on success */
294	put_device(&phy->mdio.dev);
295
296	return ret ? NULL : phy;
297}
298EXPORT_SYMBOL(of_phy_connect);
299
300/**
301 * of_phy_get_and_connect
302 * - Get phy node and connect to the phy described in the device tree
303 * @dev: pointer to net_device claiming the phy
304 * @np: Pointer to device tree node for the net_device claiming the phy
305 * @hndlr: Link state callback for the network device
306 *
307 * If successful, returns a pointer to the phy_device with the embedded
308 * struct device refcount incremented by one, or NULL on failure. The
309 * refcount must be dropped by calling phy_disconnect() or phy_detach().
310 */
311struct phy_device *of_phy_get_and_connect(struct net_device *dev,
312					  struct device_node *np,
313					  void (*hndlr)(struct net_device *))
314{
315	phy_interface_t iface;
316	struct device_node *phy_np;
317	struct phy_device *phy;
318	int ret;
319
320	ret = of_get_phy_mode(np, &iface);
321	if (ret)
322		return NULL;
323	if (of_phy_is_fixed_link(np)) {
324		ret = of_phy_register_fixed_link(np);
325		if (ret < 0) {
326			netdev_err(dev, "broken fixed-link specification\n");
327			return NULL;
328		}
329		phy_np = of_node_get(np);
330	} else {
331		phy_np = of_parse_phandle(np, "phy-handle", 0);
332		if (!phy_np)
333			return NULL;
334	}
335
336	phy = of_phy_connect(dev, phy_np, hndlr, 0, iface);
337
338	of_node_put(phy_np);
339
340	return phy;
341}
342EXPORT_SYMBOL(of_phy_get_and_connect);
343
344/*
345 * of_phy_is_fixed_link() and of_phy_register_fixed_link() must
346 * support two DT bindings:
347 * - the old DT binding, where 'fixed-link' was a property with 5
348 *   cells encoding various information about the fixed PHY
349 * - the new DT binding, where 'fixed-link' is a sub-node of the
350 *   Ethernet device.
351 */
352bool of_phy_is_fixed_link(struct device_node *np)
353{
354	struct device_node *dn;
355	int len, err;
356	const char *managed;
357
358	/* New binding */
359	dn = of_get_child_by_name(np, "fixed-link");
360	if (dn) {
361		of_node_put(dn);
362		return true;
363	}
364
365	err = of_property_read_string(np, "managed", &managed);
366	if (err == 0 && strcmp(managed, "auto") != 0)
367		return true;
368
369	/* Old binding */
370	if (of_get_property(np, "fixed-link", &len) &&
371	    len == (5 * sizeof(__be32)))
372		return true;
373
374	return false;
375}
376EXPORT_SYMBOL(of_phy_is_fixed_link);
377
378int of_phy_register_fixed_link(struct device_node *np)
379{
380	struct fixed_phy_status status = {};
381	struct device_node *fixed_link_node;
382	u32 fixed_link_prop[5];
383	const char *managed;
384
385	if (of_property_read_string(np, "managed", &managed) == 0 &&
386	    strcmp(managed, "in-band-status") == 0) {
387		/* status is zeroed, namely its .link member */
388		goto register_phy;
389	}
390
391	/* New binding */
392	fixed_link_node = of_get_child_by_name(np, "fixed-link");
393	if (fixed_link_node) {
394		status.link = 1;
395		status.duplex = of_property_read_bool(fixed_link_node,
396						      "full-duplex");
397		if (of_property_read_u32(fixed_link_node, "speed",
398					 &status.speed)) {
399			of_node_put(fixed_link_node);
400			return -EINVAL;
401		}
402		status.pause = of_property_read_bool(fixed_link_node, "pause");
403		status.asym_pause = of_property_read_bool(fixed_link_node,
404							  "asym-pause");
405		of_node_put(fixed_link_node);
406
407		goto register_phy;
408	}
409
410	/* Old binding */
411	if (of_property_read_u32_array(np, "fixed-link", fixed_link_prop,
412				       ARRAY_SIZE(fixed_link_prop)) == 0) {
413		status.link = 1;
414		status.duplex = fixed_link_prop[1];
415		status.speed  = fixed_link_prop[2];
416		status.pause  = fixed_link_prop[3];
417		status.asym_pause = fixed_link_prop[4];
418		goto register_phy;
419	}
420
421	return -ENODEV;
422
423register_phy:
424	return PTR_ERR_OR_ZERO(fixed_phy_register(PHY_POLL, &status, np));
425}
426EXPORT_SYMBOL(of_phy_register_fixed_link);
427
428void of_phy_deregister_fixed_link(struct device_node *np)
429{
430	struct phy_device *phydev;
431
432	phydev = of_phy_find_device(np);
433	if (!phydev)
434		return;
435
436	fixed_phy_unregister(phydev);
437
438	put_device(&phydev->mdio.dev);	/* of_phy_find_device() */
439	phy_device_free(phydev);	/* fixed_phy_register() */
440}
441EXPORT_SYMBOL(of_phy_deregister_fixed_link);