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v3.1
  1/*
  2 * drivers/net/phy/mdio_bus.c
  3 *
  4 * MDIO Bus interface
  5 *
  6 * Author: Andy Fleming
  7 *
  8 * Copyright (c) 2004 Freescale Semiconductor, Inc.
  9 *
 10 * This program is free software; you can redistribute  it and/or modify it
 11 * under  the terms of  the GNU General  Public License as published by the
 12 * Free Software Foundation;  either version 2 of the  License, or (at your
 13 * option) any later version.
 14 *
 15 */
 16#include <linux/kernel.h>
 17#include <linux/string.h>
 18#include <linux/errno.h>
 19#include <linux/unistd.h>
 20#include <linux/slab.h>
 21#include <linux/interrupt.h>
 22#include <linux/init.h>
 23#include <linux/delay.h>
 24#include <linux/device.h>
 25#include <linux/netdevice.h>
 26#include <linux/etherdevice.h>
 27#include <linux/skbuff.h>
 28#include <linux/spinlock.h>
 
 
 
 
 
 
 29#include <linux/mm.h>
 30#include <linux/module.h>
 31#include <linux/mii.h>
 32#include <linux/ethtool.h>
 
 
 33#include <linux/phy.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 34
 35#include <asm/io.h>
 36#include <asm/irq.h>
 37#include <asm/uaccess.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 38
 39/**
 40 * mdiobus_alloc - allocate a mii_bus structure
 
 
 41 *
 42 * Description: called by a bus driver to allocate an mii_bus
 43 * structure to fill in.
 44 */
 45struct mii_bus *mdiobus_alloc(void)
 46{
 47	struct mii_bus *bus;
 
 
 
 
 
 
 
 
 
 
 
 
 
 48
 49	bus = kzalloc(sizeof(*bus), GFP_KERNEL);
 50	if (bus != NULL)
 51		bus->state = MDIOBUS_ALLOCATED;
 
 
 
 
 
 
 52
 53	return bus;
 54}
 55EXPORT_SYMBOL(mdiobus_alloc);
 56
 57/**
 58 * mdiobus_release - mii_bus device release callback
 59 * @d: the target struct device that contains the mii_bus
 60 *
 61 * Description: called when the last reference to an mii_bus is
 62 * dropped, to free the underlying memory.
 63 */
 64static void mdiobus_release(struct device *d)
 65{
 66	struct mii_bus *bus = to_mii_bus(d);
 67	BUG_ON(bus->state != MDIOBUS_RELEASED &&
 68	       /* for compatibility with error handling in drivers */
 69	       bus->state != MDIOBUS_ALLOCATED);
 
 
 
 70	kfree(bus);
 71}
 72
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 73static struct class mdio_bus_class = {
 74	.name		= "mdio_bus",
 75	.dev_release	= mdiobus_release,
 
 76};
 77
 78/**
 79 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 80 * @bus: target mii_bus
 
 81 *
 82 * Description: Called by a bus driver to bring up all the PHYs
 83 *   on a given bus, and attach them to the bus.
 
 
 
 
 84 *
 85 * Returns 0 on success or < 0 on error.
 86 */
 87int mdiobus_register(struct mii_bus *bus)
 88{
 
 89	int i, err;
 
 90
 91	if (NULL == bus || NULL == bus->name ||
 92			NULL == bus->read ||
 93			NULL == bus->write)
 94		return -EINVAL;
 95
 96	BUG_ON(bus->state != MDIOBUS_ALLOCATED &&
 97	       bus->state != MDIOBUS_UNREGISTERED);
 
 
 
 
 
 98
 
 99	bus->dev.parent = bus->parent;
100	bus->dev.class = &mdio_bus_class;
101	bus->dev.groups = NULL;
102	dev_set_name(&bus->dev, "%s", bus->id);
103
 
 
 
 
 
 
 
104	err = device_register(&bus->dev);
105	if (err) {
106		printk(KERN_ERR "mii_bus %s failed to register\n", bus->id);
107		return -EINVAL;
108	}
109
110	mutex_init(&bus->mdio_lock);
 
111
112	if (bus->reset)
113		bus->reset(bus);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
114
115	for (i = 0; i < PHY_MAX_ADDR; i++) {
116		if ((bus->phy_mask & (1 << i)) == 0) {
117			struct phy_device *phydev;
118
119			phydev = mdiobus_scan(bus, i);
120			if (IS_ERR(phydev)) {
121				err = PTR_ERR(phydev);
122				goto error;
123			}
124		}
125	}
126
 
 
127	bus->state = MDIOBUS_REGISTERED;
128	pr_info("%s: probed\n", bus->name);
129	return 0;
130
131error:
132	while (--i >= 0) {
133		if (bus->phy_map[i])
134			device_unregister(&bus->phy_map[i]->dev);
 
 
 
 
135	}
 
 
 
 
 
136	device_del(&bus->dev);
137	return err;
138}
139EXPORT_SYMBOL(mdiobus_register);
140
141void mdiobus_unregister(struct mii_bus *bus)
142{
 
143	int i;
144
145	BUG_ON(bus->state != MDIOBUS_REGISTERED);
 
146	bus->state = MDIOBUS_UNREGISTERED;
147
148	device_del(&bus->dev);
149	for (i = 0; i < PHY_MAX_ADDR; i++) {
150		if (bus->phy_map[i])
151			device_unregister(&bus->phy_map[i]->dev);
152		bus->phy_map[i] = NULL;
 
 
 
 
 
 
153	}
 
 
 
 
 
 
154}
155EXPORT_SYMBOL(mdiobus_unregister);
156
157/**
158 * mdiobus_free - free a struct mii_bus
159 * @bus: mii_bus to free
160 *
161 * This function releases the reference to the underlying device
162 * object in the mii_bus.  If this is the last reference, the mii_bus
163 * will be freed.
164 */
165void mdiobus_free(struct mii_bus *bus)
166{
167	/*
168	 * For compatibility with error handling in drivers.
169	 */
170	if (bus->state == MDIOBUS_ALLOCATED) {
171		kfree(bus);
172		return;
173	}
174
175	BUG_ON(bus->state != MDIOBUS_UNREGISTERED);
 
176	bus->state = MDIOBUS_RELEASED;
177
178	put_device(&bus->dev);
179}
180EXPORT_SYMBOL(mdiobus_free);
181
 
 
 
 
 
 
 
 
 
 
 
 
182struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
183{
184	struct phy_device *phydev;
185	int err;
186
187	phydev = get_phy_device(bus, addr);
188	if (IS_ERR(phydev) || phydev == NULL)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
189		return phydev;
190
 
 
 
 
 
 
191	err = phy_device_register(phydev);
192	if (err) {
193		phy_device_free(phydev);
194		return NULL;
195	}
196
197	return phydev;
198}
199EXPORT_SYMBOL(mdiobus_scan);
200
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
201/**
202 * mdiobus_read - Convenience function for reading a given MII mgmt register
203 * @bus: the mii_bus struct
204 * @addr: the phy address
205 * @regnum: register number to read
206 *
207 * NOTE: MUST NOT be called from interrupt context,
208 * because the bus read/write functions may wait for an interrupt
209 * to conclude the operation.
210 */
211int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
212{
213	int retval;
214
215	BUG_ON(in_interrupt());
216
217	mutex_lock(&bus->mdio_lock);
218	retval = bus->read(bus, addr, regnum);
219	mutex_unlock(&bus->mdio_lock);
220
221	return retval;
222}
223EXPORT_SYMBOL(mdiobus_read);
224
225/**
226 * mdiobus_write - Convenience function for writing a given MII mgmt register
227 * @bus: the mii_bus struct
228 * @addr: the phy address
229 * @regnum: register number to write
230 * @val: value to write to @regnum
231 *
 
 
 
232 * NOTE: MUST NOT be called from interrupt context,
233 * because the bus read/write functions may wait for an interrupt
234 * to conclude the operation.
235 */
236int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
237{
238	int err;
239
240	BUG_ON(in_interrupt());
241
242	mutex_lock(&bus->mdio_lock);
243	err = bus->write(bus, addr, regnum, val);
244	mutex_unlock(&bus->mdio_lock);
245
246	return err;
247}
248EXPORT_SYMBOL(mdiobus_write);
249
250/**
251 * mdio_bus_match - determine if given PHY driver supports the given PHY device
252 * @dev: target PHY device
253 * @drv: given PHY driver
 
 
254 *
255 * Description: Given a PHY device, and a PHY driver, return 1 if
256 *   the driver supports the device.  Otherwise, return 0.
 
257 */
258static int mdio_bus_match(struct device *dev, struct device_driver *drv)
259{
260	struct phy_device *phydev = to_phy_device(dev);
261	struct phy_driver *phydrv = to_phy_driver(drv);
262
263	return ((phydrv->phy_id & phydrv->phy_id_mask) ==
264		(phydev->phy_id & phydrv->phy_id_mask));
265}
266
267#ifdef CONFIG_PM
 
 
268
269static bool mdio_bus_phy_may_suspend(struct phy_device *phydev)
 
 
 
 
 
 
 
 
 
270{
271	struct device_driver *drv = phydev->dev.driver;
272	struct phy_driver *phydrv = to_phy_driver(drv);
273	struct net_device *netdev = phydev->attached_dev;
274
275	if (!drv || !phydrv->suspend)
276		return false;
277
278	/* PHY not attached? May suspend. */
279	if (!netdev)
280		return true;
281
282	/*
283	 * Don't suspend PHY if the attched netdev parent may wakeup.
284	 * The parent may point to a PCI device, as in tg3 driver.
285	 */
286	if (netdev->dev.parent && device_may_wakeup(netdev->dev.parent))
287		return false;
288
289	/*
290	 * Also don't suspend PHY if the netdev itself may wakeup. This
291	 * is the case for devices w/o underlaying pwr. mgmt. aware bus,
292	 * e.g. SoC devices.
293	 */
294	if (device_may_wakeup(&netdev->dev))
295		return false;
296
297	return true;
298}
 
299
300static int mdio_bus_suspend(struct device *dev)
 
 
 
 
 
 
 
 
 
 
301{
302	struct phy_driver *phydrv = to_phy_driver(dev->driver);
303	struct phy_device *phydev = to_phy_device(dev);
304
305	/*
306	 * We must stop the state machine manually, otherwise it stops out of
307	 * control, possibly with the phydev->lock held. Upon resume, netdev
308	 * may call phy routines that try to grab the same lock, and that may
309	 * lead to a deadlock.
310	 */
311	if (phydev->attached_dev && phydev->adjust_link)
312		phy_stop_machine(phydev);
313
314	if (!mdio_bus_phy_may_suspend(phydev))
315		return 0;
 
316
317	return phydrv->suspend(phydev);
318}
 
319
320static int mdio_bus_resume(struct device *dev)
 
 
 
 
 
 
 
 
 
 
 
321{
322	struct phy_driver *phydrv = to_phy_driver(dev->driver);
323	struct phy_device *phydev = to_phy_device(dev);
324	int ret;
325
326	if (!mdio_bus_phy_may_suspend(phydev))
327		goto no_resume;
 
 
328
329	ret = phydrv->resume(phydev);
330	if (ret < 0)
331		return ret;
332
333no_resume:
334	if (phydev->attached_dev && phydev->adjust_link)
335		phy_start_machine(phydev, NULL);
336
337	return 0;
338}
339
340static int mdio_bus_restore(struct device *dev)
341{
342	struct phy_device *phydev = to_phy_device(dev);
343	struct net_device *netdev = phydev->attached_dev;
344	int ret;
345
346	if (!netdev)
347		return 0;
348
349	ret = phy_init_hw(phydev);
350	if (ret < 0)
351		return ret;
352
353	/* The PHY needs to renegotiate. */
354	phydev->link = 0;
355	phydev->state = PHY_UP;
356
357	phy_start_machine(phydev, NULL);
358
359	return 0;
360}
361
362static struct dev_pm_ops mdio_bus_pm_ops = {
363	.suspend = mdio_bus_suspend,
364	.resume = mdio_bus_resume,
365	.freeze = mdio_bus_suspend,
366	.thaw = mdio_bus_resume,
367	.restore = mdio_bus_restore,
368};
369
370#define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
371
372#else
373
374#define MDIO_BUS_PM_OPS NULL
375
376#endif /* CONFIG_PM */
 
 
 
377
378struct bus_type mdio_bus_type = {
379	.name		= "mdio_bus",
 
380	.match		= mdio_bus_match,
381	.pm		= MDIO_BUS_PM_OPS,
382};
383EXPORT_SYMBOL(mdio_bus_type);
384
385int __init mdio_bus_init(void)
386{
387	int ret;
388
389	ret = class_register(&mdio_bus_class);
390	if (!ret) {
391		ret = bus_register(&mdio_bus_type);
392		if (ret)
393			class_unregister(&mdio_bus_class);
394	}
395
396	return ret;
397}
398
 
399void mdio_bus_exit(void)
400{
401	class_unregister(&mdio_bus_class);
402	bus_unregister(&mdio_bus_type);
403}
v6.2
   1// SPDX-License-Identifier: GPL-2.0+
   2/* MDIO Bus interface
 
 
   3 *
   4 * Author: Andy Fleming
   5 *
   6 * Copyright (c) 2004 Freescale Semiconductor, Inc.
 
 
 
 
 
 
   7 */
   8
   9#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  10
 
 
 
 
  11#include <linux/delay.h>
  12#include <linux/device.h>
  13#include <linux/errno.h>
  14#include <linux/etherdevice.h>
  15#include <linux/ethtool.h>
  16#include <linux/gpio.h>
  17#include <linux/gpio/consumer.h>
  18#include <linux/init.h>
  19#include <linux/interrupt.h>
  20#include <linux/io.h>
  21#include <linux/kernel.h>
  22#include <linux/mii.h>
  23#include <linux/mm.h>
  24#include <linux/module.h>
  25#include <linux/netdevice.h>
  26#include <linux/of_device.h>
  27#include <linux/of_gpio.h>
  28#include <linux/of_mdio.h>
  29#include <linux/phy.h>
  30#include <linux/reset.h>
  31#include <linux/skbuff.h>
  32#include <linux/slab.h>
  33#include <linux/spinlock.h>
  34#include <linux/string.h>
  35#include <linux/uaccess.h>
  36#include <linux/unistd.h>
  37
  38#define CREATE_TRACE_POINTS
  39#include <trace/events/mdio.h>
  40
  41#include "mdio-boardinfo.h"
  42
  43static int mdiobus_register_gpiod(struct mdio_device *mdiodev)
  44{
  45	/* Deassert the optional reset signal */
  46	mdiodev->reset_gpio = gpiod_get_optional(&mdiodev->dev,
  47						 "reset", GPIOD_OUT_LOW);
  48	if (IS_ERR(mdiodev->reset_gpio))
  49		return PTR_ERR(mdiodev->reset_gpio);
  50
  51	if (mdiodev->reset_gpio)
  52		gpiod_set_consumer_name(mdiodev->reset_gpio, "PHY reset");
  53
  54	return 0;
  55}
  56
  57static int mdiobus_register_reset(struct mdio_device *mdiodev)
  58{
  59	struct reset_control *reset;
  60
  61	reset = reset_control_get_optional_exclusive(&mdiodev->dev, "phy");
  62	if (IS_ERR(reset))
  63		return PTR_ERR(reset);
  64
  65	mdiodev->reset_ctrl = reset;
  66
  67	return 0;
  68}
  69
  70int mdiobus_register_device(struct mdio_device *mdiodev)
  71{
  72	int err;
  73
  74	if (mdiodev->bus->mdio_map[mdiodev->addr])
  75		return -EBUSY;
  76
  77	if (mdiodev->flags & MDIO_DEVICE_FLAG_PHY) {
  78		err = mdiobus_register_gpiod(mdiodev);
  79		if (err)
  80			return err;
  81
  82		err = mdiobus_register_reset(mdiodev);
  83		if (err)
  84			return err;
  85
  86		/* Assert the reset signal */
  87		mdio_device_reset(mdiodev, 1);
  88	}
  89
  90	mdiodev->bus->mdio_map[mdiodev->addr] = mdiodev;
  91
  92	return 0;
  93}
  94EXPORT_SYMBOL(mdiobus_register_device);
  95
  96int mdiobus_unregister_device(struct mdio_device *mdiodev)
  97{
  98	if (mdiodev->bus->mdio_map[mdiodev->addr] != mdiodev)
  99		return -EINVAL;
 100
 101	reset_control_put(mdiodev->reset_ctrl);
 102
 103	mdiodev->bus->mdio_map[mdiodev->addr] = NULL;
 104
 105	return 0;
 106}
 107EXPORT_SYMBOL(mdiobus_unregister_device);
 108
 109struct phy_device *mdiobus_get_phy(struct mii_bus *bus, int addr)
 110{
 111	struct mdio_device *mdiodev;
 112
 113	if (addr < 0 || addr >= ARRAY_SIZE(bus->mdio_map))
 114		return NULL;
 115
 116	mdiodev = bus->mdio_map[addr];
 117
 118	if (!mdiodev)
 119		return NULL;
 120
 121	if (!(mdiodev->flags & MDIO_DEVICE_FLAG_PHY))
 122		return NULL;
 123
 124	return container_of(mdiodev, struct phy_device, mdio);
 125}
 126EXPORT_SYMBOL(mdiobus_get_phy);
 127
 128bool mdiobus_is_registered_device(struct mii_bus *bus, int addr)
 129{
 130	return bus->mdio_map[addr];
 131}
 132EXPORT_SYMBOL(mdiobus_is_registered_device);
 133
 134/**
 135 * mdiobus_alloc_size - allocate a mii_bus structure
 136 * @size: extra amount of memory to allocate for private storage.
 137 * If non-zero, then bus->priv is points to that memory.
 138 *
 139 * Description: called by a bus driver to allocate an mii_bus
 140 * structure to fill in.
 141 */
 142struct mii_bus *mdiobus_alloc_size(size_t size)
 143{
 144	struct mii_bus *bus;
 145	size_t aligned_size = ALIGN(sizeof(*bus), NETDEV_ALIGN);
 146	size_t alloc_size;
 147	int i;
 148
 149	/* If we alloc extra space, it should be aligned */
 150	if (size)
 151		alloc_size = aligned_size + size;
 152	else
 153		alloc_size = sizeof(*bus);
 154
 155	bus = kzalloc(alloc_size, GFP_KERNEL);
 156	if (!bus)
 157		return NULL;
 158
 159	bus->state = MDIOBUS_ALLOCATED;
 160	if (size)
 161		bus->priv = (void *)bus + aligned_size;
 162
 163	/* Initialise the interrupts to polling and 64-bit seqcounts */
 164	for (i = 0; i < PHY_MAX_ADDR; i++) {
 165		bus->irq[i] = PHY_POLL;
 166		u64_stats_init(&bus->stats[i].syncp);
 167	}
 168
 169	return bus;
 170}
 171EXPORT_SYMBOL(mdiobus_alloc_size);
 172
 173/**
 174 * mdiobus_release - mii_bus device release callback
 175 * @d: the target struct device that contains the mii_bus
 176 *
 177 * Description: called when the last reference to an mii_bus is
 178 * dropped, to free the underlying memory.
 179 */
 180static void mdiobus_release(struct device *d)
 181{
 182	struct mii_bus *bus = to_mii_bus(d);
 183
 184	WARN(bus->state != MDIOBUS_RELEASED &&
 185	     /* for compatibility with error handling in drivers */
 186	     bus->state != MDIOBUS_ALLOCATED,
 187	     "%s: not in RELEASED or ALLOCATED state\n",
 188	     bus->id);
 189	kfree(bus);
 190}
 191
 192struct mdio_bus_stat_attr {
 193	int addr;
 194	unsigned int field_offset;
 195};
 196
 197static u64 mdio_bus_get_stat(struct mdio_bus_stats *s, unsigned int offset)
 198{
 199	const char *p = (const char *)s + offset;
 200	unsigned int start;
 201	u64 val = 0;
 202
 203	do {
 204		start = u64_stats_fetch_begin(&s->syncp);
 205		val = u64_stats_read((const u64_stats_t *)p);
 206	} while (u64_stats_fetch_retry(&s->syncp, start));
 207
 208	return val;
 209}
 210
 211static u64 mdio_bus_get_global_stat(struct mii_bus *bus, unsigned int offset)
 212{
 213	unsigned int i;
 214	u64 val = 0;
 215
 216	for (i = 0; i < PHY_MAX_ADDR; i++)
 217		val += mdio_bus_get_stat(&bus->stats[i], offset);
 218
 219	return val;
 220}
 221
 222static ssize_t mdio_bus_stat_field_show(struct device *dev,
 223					struct device_attribute *attr,
 224					char *buf)
 225{
 226	struct mii_bus *bus = to_mii_bus(dev);
 227	struct mdio_bus_stat_attr *sattr;
 228	struct dev_ext_attribute *eattr;
 229	u64 val;
 230
 231	eattr = container_of(attr, struct dev_ext_attribute, attr);
 232	sattr = eattr->var;
 233
 234	if (sattr->addr < 0)
 235		val = mdio_bus_get_global_stat(bus, sattr->field_offset);
 236	else
 237		val = mdio_bus_get_stat(&bus->stats[sattr->addr],
 238					sattr->field_offset);
 239
 240	return sysfs_emit(buf, "%llu\n", val);
 241}
 242
 243static ssize_t mdio_bus_device_stat_field_show(struct device *dev,
 244					       struct device_attribute *attr,
 245					       char *buf)
 246{
 247	struct mdio_device *mdiodev = to_mdio_device(dev);
 248	struct mii_bus *bus = mdiodev->bus;
 249	struct mdio_bus_stat_attr *sattr;
 250	struct dev_ext_attribute *eattr;
 251	int addr = mdiodev->addr;
 252	u64 val;
 253
 254	eattr = container_of(attr, struct dev_ext_attribute, attr);
 255	sattr = eattr->var;
 256
 257	val = mdio_bus_get_stat(&bus->stats[addr], sattr->field_offset);
 258
 259	return sysfs_emit(buf, "%llu\n", val);
 260}
 261
 262#define MDIO_BUS_STATS_ATTR_DECL(field, file)				\
 263static struct dev_ext_attribute dev_attr_mdio_bus_##field = {		\
 264	.attr = { .attr = { .name = file, .mode = 0444 },		\
 265		     .show = mdio_bus_stat_field_show,			\
 266	},								\
 267	.var = &((struct mdio_bus_stat_attr) {				\
 268		-1, offsetof(struct mdio_bus_stats, field)		\
 269	}),								\
 270};									\
 271static struct dev_ext_attribute dev_attr_mdio_bus_device_##field = {	\
 272	.attr = { .attr = { .name = file, .mode = 0444 },		\
 273		     .show = mdio_bus_device_stat_field_show,		\
 274	},								\
 275	.var = &((struct mdio_bus_stat_attr) {				\
 276		-1, offsetof(struct mdio_bus_stats, field)		\
 277	}),								\
 278};
 279
 280#define MDIO_BUS_STATS_ATTR(field)					\
 281	MDIO_BUS_STATS_ATTR_DECL(field, __stringify(field))
 282
 283MDIO_BUS_STATS_ATTR(transfers);
 284MDIO_BUS_STATS_ATTR(errors);
 285MDIO_BUS_STATS_ATTR(writes);
 286MDIO_BUS_STATS_ATTR(reads);
 287
 288#define MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr, file)		\
 289static struct dev_ext_attribute dev_attr_mdio_bus_addr_##field##_##addr = { \
 290	.attr = { .attr = { .name = file, .mode = 0444 },		\
 291		     .show = mdio_bus_stat_field_show,			\
 292	},								\
 293	.var = &((struct mdio_bus_stat_attr) {				\
 294		addr, offsetof(struct mdio_bus_stats, field)		\
 295	}),								\
 296}
 297
 298#define MDIO_BUS_STATS_ADDR_ATTR(field, addr)				\
 299	MDIO_BUS_STATS_ADDR_ATTR_DECL(field, addr,			\
 300				 __stringify(field) "_" __stringify(addr))
 301
 302#define MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(addr)			\
 303	MDIO_BUS_STATS_ADDR_ATTR(transfers, addr);			\
 304	MDIO_BUS_STATS_ADDR_ATTR(errors, addr);				\
 305	MDIO_BUS_STATS_ADDR_ATTR(writes, addr);				\
 306	MDIO_BUS_STATS_ADDR_ATTR(reads, addr)				\
 307
 308MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(0);
 309MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(1);
 310MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(2);
 311MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(3);
 312MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(4);
 313MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(5);
 314MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(6);
 315MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(7);
 316MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(8);
 317MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(9);
 318MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(10);
 319MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(11);
 320MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(12);
 321MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(13);
 322MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(14);
 323MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(15);
 324MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(16);
 325MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(17);
 326MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(18);
 327MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(19);
 328MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(20);
 329MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(21);
 330MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(22);
 331MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(23);
 332MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(24);
 333MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(25);
 334MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(26);
 335MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(27);
 336MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(28);
 337MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(29);
 338MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(30);
 339MDIO_BUS_STATS_ADDR_ATTR_GROUP_DECL(31);
 340
 341#define MDIO_BUS_STATS_ADDR_ATTR_GROUP(addr)				\
 342	&dev_attr_mdio_bus_addr_transfers_##addr.attr.attr,		\
 343	&dev_attr_mdio_bus_addr_errors_##addr.attr.attr,		\
 344	&dev_attr_mdio_bus_addr_writes_##addr.attr.attr,		\
 345	&dev_attr_mdio_bus_addr_reads_##addr.attr.attr			\
 346
 347static struct attribute *mdio_bus_statistics_attrs[] = {
 348	&dev_attr_mdio_bus_transfers.attr.attr,
 349	&dev_attr_mdio_bus_errors.attr.attr,
 350	&dev_attr_mdio_bus_writes.attr.attr,
 351	&dev_attr_mdio_bus_reads.attr.attr,
 352	MDIO_BUS_STATS_ADDR_ATTR_GROUP(0),
 353	MDIO_BUS_STATS_ADDR_ATTR_GROUP(1),
 354	MDIO_BUS_STATS_ADDR_ATTR_GROUP(2),
 355	MDIO_BUS_STATS_ADDR_ATTR_GROUP(3),
 356	MDIO_BUS_STATS_ADDR_ATTR_GROUP(4),
 357	MDIO_BUS_STATS_ADDR_ATTR_GROUP(5),
 358	MDIO_BUS_STATS_ADDR_ATTR_GROUP(6),
 359	MDIO_BUS_STATS_ADDR_ATTR_GROUP(7),
 360	MDIO_BUS_STATS_ADDR_ATTR_GROUP(8),
 361	MDIO_BUS_STATS_ADDR_ATTR_GROUP(9),
 362	MDIO_BUS_STATS_ADDR_ATTR_GROUP(10),
 363	MDIO_BUS_STATS_ADDR_ATTR_GROUP(11),
 364	MDIO_BUS_STATS_ADDR_ATTR_GROUP(12),
 365	MDIO_BUS_STATS_ADDR_ATTR_GROUP(13),
 366	MDIO_BUS_STATS_ADDR_ATTR_GROUP(14),
 367	MDIO_BUS_STATS_ADDR_ATTR_GROUP(15),
 368	MDIO_BUS_STATS_ADDR_ATTR_GROUP(16),
 369	MDIO_BUS_STATS_ADDR_ATTR_GROUP(17),
 370	MDIO_BUS_STATS_ADDR_ATTR_GROUP(18),
 371	MDIO_BUS_STATS_ADDR_ATTR_GROUP(19),
 372	MDIO_BUS_STATS_ADDR_ATTR_GROUP(20),
 373	MDIO_BUS_STATS_ADDR_ATTR_GROUP(21),
 374	MDIO_BUS_STATS_ADDR_ATTR_GROUP(22),
 375	MDIO_BUS_STATS_ADDR_ATTR_GROUP(23),
 376	MDIO_BUS_STATS_ADDR_ATTR_GROUP(24),
 377	MDIO_BUS_STATS_ADDR_ATTR_GROUP(25),
 378	MDIO_BUS_STATS_ADDR_ATTR_GROUP(26),
 379	MDIO_BUS_STATS_ADDR_ATTR_GROUP(27),
 380	MDIO_BUS_STATS_ADDR_ATTR_GROUP(28),
 381	MDIO_BUS_STATS_ADDR_ATTR_GROUP(29),
 382	MDIO_BUS_STATS_ADDR_ATTR_GROUP(30),
 383	MDIO_BUS_STATS_ADDR_ATTR_GROUP(31),
 384	NULL,
 385};
 386
 387static const struct attribute_group mdio_bus_statistics_group = {
 388	.name	= "statistics",
 389	.attrs	= mdio_bus_statistics_attrs,
 390};
 391
 392static const struct attribute_group *mdio_bus_groups[] = {
 393	&mdio_bus_statistics_group,
 394	NULL,
 395};
 396
 397static struct class mdio_bus_class = {
 398	.name		= "mdio_bus",
 399	.dev_release	= mdiobus_release,
 400	.dev_groups	= mdio_bus_groups,
 401};
 402
 403/**
 404 * mdio_find_bus - Given the name of a mdiobus, find the mii_bus.
 405 * @mdio_name: The name of a mdiobus.
 406 *
 407 * Returns a reference to the mii_bus, or NULL if none found.  The
 408 * embedded struct device will have its reference count incremented,
 409 * and this must be put_deviced'ed once the bus is finished with.
 410 */
 411struct mii_bus *mdio_find_bus(const char *mdio_name)
 412{
 413	struct device *d;
 414
 415	d = class_find_device_by_name(&mdio_bus_class, mdio_name);
 416	return d ? to_mii_bus(d) : NULL;
 417}
 418EXPORT_SYMBOL(mdio_find_bus);
 419
 420#if IS_ENABLED(CONFIG_OF_MDIO)
 421/**
 422 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
 423 * @mdio_bus_np: Pointer to the mii_bus.
 424 *
 425 * Returns a reference to the mii_bus, or NULL if none found.  The
 426 * embedded struct device will have its reference count incremented,
 427 * and this must be put once the bus is finished with.
 428 *
 429 * Because the association of a device_node and mii_bus is made via
 430 * of_mdiobus_register(), the mii_bus cannot be found before it is
 431 * registered with of_mdiobus_register().
 432 *
 433 */
 434struct mii_bus *of_mdio_find_bus(struct device_node *mdio_bus_np)
 435{
 436	struct device *d;
 437
 438	if (!mdio_bus_np)
 439		return NULL;
 440
 441	d = class_find_device_by_of_node(&mdio_bus_class, mdio_bus_np);
 442	return d ? to_mii_bus(d) : NULL;
 443}
 444EXPORT_SYMBOL(of_mdio_find_bus);
 445
 446/* Walk the list of subnodes of a mdio bus and look for a node that
 447 * matches the mdio device's address with its 'reg' property. If
 448 * found, set the of_node pointer for the mdio device. This allows
 449 * auto-probed phy devices to be supplied with information passed in
 450 * via DT.
 451 */
 452static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
 453				    struct mdio_device *mdiodev)
 454{
 455	struct device *dev = &mdiodev->dev;
 456	struct device_node *child;
 457
 458	if (dev->of_node || !bus->dev.of_node)
 459		return;
 460
 461	for_each_available_child_of_node(bus->dev.of_node, child) {
 462		int addr;
 463
 464		addr = of_mdio_parse_addr(dev, child);
 465		if (addr < 0)
 466			continue;
 467
 468		if (addr == mdiodev->addr) {
 469			device_set_node(dev, of_fwnode_handle(child));
 470			/* The refcount on "child" is passed to the mdio
 471			 * device. Do _not_ use of_node_put(child) here.
 472			 */
 473			return;
 474		}
 475	}
 476}
 477#else /* !IS_ENABLED(CONFIG_OF_MDIO) */
 478static inline void of_mdiobus_link_mdiodev(struct mii_bus *mdio,
 479					   struct mdio_device *mdiodev)
 480{
 481}
 482#endif
 483
 484/**
 485 * mdiobus_create_device - create a full MDIO device given
 486 * a mdio_board_info structure
 487 * @bus: MDIO bus to create the devices on
 488 * @bi: mdio_board_info structure describing the devices
 489 *
 490 * Returns 0 on success or < 0 on error.
 491 */
 492static int mdiobus_create_device(struct mii_bus *bus,
 493				 struct mdio_board_info *bi)
 494{
 495	struct mdio_device *mdiodev;
 496	int ret = 0;
 497
 498	mdiodev = mdio_device_create(bus, bi->mdio_addr);
 499	if (IS_ERR(mdiodev))
 500		return -ENODEV;
 501
 502	strncpy(mdiodev->modalias, bi->modalias,
 503		sizeof(mdiodev->modalias));
 504	mdiodev->bus_match = mdio_device_bus_match;
 505	mdiodev->dev.platform_data = (void *)bi->platform_data;
 506
 507	ret = mdio_device_register(mdiodev);
 508	if (ret)
 509		mdio_device_free(mdiodev);
 510
 511	return ret;
 512}
 513
 514/**
 515 * __mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
 516 * @bus: target mii_bus
 517 * @owner: module containing bus accessor functions
 518 *
 519 * Description: Called by a bus driver to bring up all the PHYs
 520 *   on a given bus, and attach them to the bus. Drivers should use
 521 *   mdiobus_register() rather than __mdiobus_register() unless they
 522 *   need to pass a specific owner module. MDIO devices which are not
 523 *   PHYs will not be brought up by this function. They are expected
 524 *   to be explicitly listed in DT and instantiated by of_mdiobus_register().
 525 *
 526 * Returns 0 on success or < 0 on error.
 527 */
 528int __mdiobus_register(struct mii_bus *bus, struct module *owner)
 529{
 530	struct mdio_device *mdiodev;
 531	int i, err;
 532	struct gpio_desc *gpiod;
 533
 534	if (NULL == bus || NULL == bus->name ||
 535	    NULL == bus->read || NULL == bus->write)
 
 536		return -EINVAL;
 537
 538	if (bus->parent && bus->parent->of_node)
 539		bus->parent->of_node->fwnode.flags |=
 540					FWNODE_FLAG_NEEDS_CHILD_BOUND_ON_ADD;
 541
 542	WARN(bus->state != MDIOBUS_ALLOCATED &&
 543	     bus->state != MDIOBUS_UNREGISTERED,
 544	     "%s: not in ALLOCATED or UNREGISTERED state\n", bus->id);
 545
 546	bus->owner = owner;
 547	bus->dev.parent = bus->parent;
 548	bus->dev.class = &mdio_bus_class;
 549	bus->dev.groups = NULL;
 550	dev_set_name(&bus->dev, "%s", bus->id);
 551
 552	/* We need to set state to MDIOBUS_UNREGISTERED to correctly release
 553	 * the device in mdiobus_free()
 554	 *
 555	 * State will be updated later in this function in case of success
 556	 */
 557	bus->state = MDIOBUS_UNREGISTERED;
 558
 559	err = device_register(&bus->dev);
 560	if (err) {
 561		pr_err("mii_bus %s failed to register\n", bus->id);
 562		return -EINVAL;
 563	}
 564
 565	mutex_init(&bus->mdio_lock);
 566	mutex_init(&bus->shared_lock);
 567
 568	/* assert bus level PHY GPIO reset */
 569	gpiod = devm_gpiod_get_optional(&bus->dev, "reset", GPIOD_OUT_HIGH);
 570	if (IS_ERR(gpiod)) {
 571		err = dev_err_probe(&bus->dev, PTR_ERR(gpiod),
 572				    "mii_bus %s couldn't get reset GPIO\n",
 573				    bus->id);
 574		device_del(&bus->dev);
 575		return err;
 576	} else	if (gpiod) {
 577		bus->reset_gpiod = gpiod;
 578		fsleep(bus->reset_delay_us);
 579		gpiod_set_value_cansleep(gpiod, 0);
 580		if (bus->reset_post_delay_us > 0)
 581			fsleep(bus->reset_post_delay_us);
 582	}
 583
 584	if (bus->reset) {
 585		err = bus->reset(bus);
 586		if (err)
 587			goto error_reset_gpiod;
 588	}
 589
 590	for (i = 0; i < PHY_MAX_ADDR; i++) {
 591		if ((bus->phy_mask & BIT(i)) == 0) {
 592			struct phy_device *phydev;
 593
 594			phydev = mdiobus_scan(bus, i);
 595			if (IS_ERR(phydev) && (PTR_ERR(phydev) != -ENODEV)) {
 596				err = PTR_ERR(phydev);
 597				goto error;
 598			}
 599		}
 600	}
 601
 602	mdiobus_setup_mdiodev_from_board_info(bus, mdiobus_create_device);
 603
 604	bus->state = MDIOBUS_REGISTERED;
 605	dev_dbg(&bus->dev, "probed\n");
 606	return 0;
 607
 608error:
 609	while (--i >= 0) {
 610		mdiodev = bus->mdio_map[i];
 611		if (!mdiodev)
 612			continue;
 613
 614		mdiodev->device_remove(mdiodev);
 615		mdiodev->device_free(mdiodev);
 616	}
 617error_reset_gpiod:
 618	/* Put PHYs in RESET to save power */
 619	if (bus->reset_gpiod)
 620		gpiod_set_value_cansleep(bus->reset_gpiod, 1);
 621
 622	device_del(&bus->dev);
 623	return err;
 624}
 625EXPORT_SYMBOL(__mdiobus_register);
 626
 627void mdiobus_unregister(struct mii_bus *bus)
 628{
 629	struct mdio_device *mdiodev;
 630	int i;
 631
 632	if (WARN_ON_ONCE(bus->state != MDIOBUS_REGISTERED))
 633		return;
 634	bus->state = MDIOBUS_UNREGISTERED;
 635
 
 636	for (i = 0; i < PHY_MAX_ADDR; i++) {
 637		mdiodev = bus->mdio_map[i];
 638		if (!mdiodev)
 639			continue;
 640
 641		if (mdiodev->reset_gpio)
 642			gpiod_put(mdiodev->reset_gpio);
 643
 644		mdiodev->device_remove(mdiodev);
 645		mdiodev->device_free(mdiodev);
 646	}
 647
 648	/* Put PHYs in RESET to save power */
 649	if (bus->reset_gpiod)
 650		gpiod_set_value_cansleep(bus->reset_gpiod, 1);
 651
 652	device_del(&bus->dev);
 653}
 654EXPORT_SYMBOL(mdiobus_unregister);
 655
 656/**
 657 * mdiobus_free - free a struct mii_bus
 658 * @bus: mii_bus to free
 659 *
 660 * This function releases the reference to the underlying device
 661 * object in the mii_bus.  If this is the last reference, the mii_bus
 662 * will be freed.
 663 */
 664void mdiobus_free(struct mii_bus *bus)
 665{
 666	/* For compatibility with error handling in drivers. */
 
 
 667	if (bus->state == MDIOBUS_ALLOCATED) {
 668		kfree(bus);
 669		return;
 670	}
 671
 672	WARN(bus->state != MDIOBUS_UNREGISTERED,
 673	     "%s: not in UNREGISTERED state\n", bus->id);
 674	bus->state = MDIOBUS_RELEASED;
 675
 676	put_device(&bus->dev);
 677}
 678EXPORT_SYMBOL(mdiobus_free);
 679
 680/**
 681 * mdiobus_scan - scan a bus for MDIO devices.
 682 * @bus: mii_bus to scan
 683 * @addr: address on bus to scan
 684 *
 685 * This function scans the MDIO bus, looking for devices which can be
 686 * identified using a vendor/product ID in registers 2 and 3. Not all
 687 * MDIO devices have such registers, but PHY devices typically
 688 * do. Hence this function assumes anything found is a PHY, or can be
 689 * treated as a PHY. Other MDIO devices, such as switches, will
 690 * probably not be found during the scan.
 691 */
 692struct phy_device *mdiobus_scan(struct mii_bus *bus, int addr)
 693{
 694	struct phy_device *phydev = ERR_PTR(-ENODEV);
 695	int err;
 696
 697	switch (bus->probe_capabilities) {
 698	case MDIOBUS_NO_CAP:
 699	case MDIOBUS_C22:
 700		phydev = get_phy_device(bus, addr, false);
 701		break;
 702	case MDIOBUS_C45:
 703		phydev = get_phy_device(bus, addr, true);
 704		break;
 705	case MDIOBUS_C22_C45:
 706		phydev = get_phy_device(bus, addr, false);
 707		if (IS_ERR(phydev))
 708			phydev = get_phy_device(bus, addr, true);
 709		break;
 710	}
 711
 712	if (IS_ERR(phydev))
 713		return phydev;
 714
 715	/*
 716	 * For DT, see if the auto-probed phy has a correspoding child
 717	 * in the bus node, and set the of_node pointer in this case.
 718	 */
 719	of_mdiobus_link_mdiodev(bus, &phydev->mdio);
 720
 721	err = phy_device_register(phydev);
 722	if (err) {
 723		phy_device_free(phydev);
 724		return ERR_PTR(-ENODEV);
 725	}
 726
 727	return phydev;
 728}
 729EXPORT_SYMBOL(mdiobus_scan);
 730
 731static void mdiobus_stats_acct(struct mdio_bus_stats *stats, bool op, int ret)
 732{
 733	preempt_disable();
 734	u64_stats_update_begin(&stats->syncp);
 735
 736	u64_stats_inc(&stats->transfers);
 737	if (ret < 0) {
 738		u64_stats_inc(&stats->errors);
 739		goto out;
 740	}
 741
 742	if (op)
 743		u64_stats_inc(&stats->reads);
 744	else
 745		u64_stats_inc(&stats->writes);
 746out:
 747	u64_stats_update_end(&stats->syncp);
 748	preempt_enable();
 749}
 750
 751/**
 752 * __mdiobus_read - Unlocked version of the mdiobus_read function
 753 * @bus: the mii_bus struct
 754 * @addr: the phy address
 755 * @regnum: register number to read
 756 *
 757 * Read a MDIO bus register. Caller must hold the mdio bus lock.
 758 *
 759 * NOTE: MUST NOT be called from interrupt context.
 760 */
 761int __mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
 762{
 763	int retval;
 764
 765	lockdep_assert_held_once(&bus->mdio_lock);
 766
 767	retval = bus->read(bus, addr, regnum);
 768
 769	trace_mdio_access(bus, 1, addr, regnum, retval, retval);
 770	mdiobus_stats_acct(&bus->stats[addr], true, retval);
 771
 772	return retval;
 773}
 774EXPORT_SYMBOL(__mdiobus_read);
 775
 776/**
 777 * __mdiobus_write - Unlocked version of the mdiobus_write function
 778 * @bus: the mii_bus struct
 779 * @addr: the phy address
 780 * @regnum: register number to write
 781 * @val: value to write to @regnum
 782 *
 783 * Write a MDIO bus register. Caller must hold the mdio bus lock.
 784 *
 785 * NOTE: MUST NOT be called from interrupt context.
 786 */
 787int __mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
 788{
 789	int err;
 790
 791	lockdep_assert_held_once(&bus->mdio_lock);
 792
 793	err = bus->write(bus, addr, regnum, val);
 794
 795	trace_mdio_access(bus, 0, addr, regnum, val, err);
 796	mdiobus_stats_acct(&bus->stats[addr], false, err);
 797
 798	return err;
 799}
 800EXPORT_SYMBOL(__mdiobus_write);
 801
 802/**
 803 * __mdiobus_modify_changed - Unlocked version of the mdiobus_modify function
 804 * @bus: the mii_bus struct
 805 * @addr: the phy address
 806 * @regnum: register number to modify
 807 * @mask: bit mask of bits to clear
 808 * @set: bit mask of bits to set
 809 *
 810 * Read, modify, and if any change, write the register value back to the
 811 * device. Any error returns a negative number.
 812 *
 813 * NOTE: MUST NOT be called from interrupt context.
 814 */
 815int __mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
 816			     u16 mask, u16 set)
 817{
 818	int new, ret;
 819
 820	ret = __mdiobus_read(bus, addr, regnum);
 821	if (ret < 0)
 822		return ret;
 823
 824	new = (ret & ~mask) | set;
 825	if (new == ret)
 826		return 0;
 827
 828	ret = __mdiobus_write(bus, addr, regnum, new);
 829
 830	return ret < 0 ? ret : 1;
 831}
 832EXPORT_SYMBOL_GPL(__mdiobus_modify_changed);
 833
 834/**
 835 * mdiobus_read_nested - Nested version of the mdiobus_read function
 836 * @bus: the mii_bus struct
 837 * @addr: the phy address
 838 * @regnum: register number to read
 839 *
 840 * In case of nested MDIO bus access avoid lockdep false positives by
 841 * using mutex_lock_nested().
 842 *
 843 * NOTE: MUST NOT be called from interrupt context,
 844 * because the bus read/write functions may wait for an interrupt
 845 * to conclude the operation.
 846 */
 847int mdiobus_read_nested(struct mii_bus *bus, int addr, u32 regnum)
 848{
 849	int retval;
 850
 851	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
 852	retval = __mdiobus_read(bus, addr, regnum);
 853	mutex_unlock(&bus->mdio_lock);
 854
 855	return retval;
 856}
 857EXPORT_SYMBOL(mdiobus_read_nested);
 858
 859/**
 860 * mdiobus_read - Convenience function for reading a given MII mgmt register
 861 * @bus: the mii_bus struct
 862 * @addr: the phy address
 863 * @regnum: register number to read
 864 *
 865 * NOTE: MUST NOT be called from interrupt context,
 866 * because the bus read/write functions may wait for an interrupt
 867 * to conclude the operation.
 868 */
 869int mdiobus_read(struct mii_bus *bus, int addr, u32 regnum)
 870{
 871	int retval;
 872
 
 
 873	mutex_lock(&bus->mdio_lock);
 874	retval = __mdiobus_read(bus, addr, regnum);
 875	mutex_unlock(&bus->mdio_lock);
 876
 877	return retval;
 878}
 879EXPORT_SYMBOL(mdiobus_read);
 880
 881/**
 882 * mdiobus_write_nested - Nested version of the mdiobus_write function
 883 * @bus: the mii_bus struct
 884 * @addr: the phy address
 885 * @regnum: register number to write
 886 * @val: value to write to @regnum
 887 *
 888 * In case of nested MDIO bus access avoid lockdep false positives by
 889 * using mutex_lock_nested().
 890 *
 891 * NOTE: MUST NOT be called from interrupt context,
 892 * because the bus read/write functions may wait for an interrupt
 893 * to conclude the operation.
 894 */
 895int mdiobus_write_nested(struct mii_bus *bus, int addr, u32 regnum, u16 val)
 896{
 897	int err;
 898
 899	mutex_lock_nested(&bus->mdio_lock, MDIO_MUTEX_NESTED);
 900	err = __mdiobus_write(bus, addr, regnum, val);
 
 
 901	mutex_unlock(&bus->mdio_lock);
 902
 903	return err;
 904}
 905EXPORT_SYMBOL(mdiobus_write_nested);
 906
 907/**
 908 * mdiobus_write - Convenience function for writing a given MII mgmt register
 909 * @bus: the mii_bus struct
 910 * @addr: the phy address
 911 * @regnum: register number to write
 912 * @val: value to write to @regnum
 913 *
 914 * NOTE: MUST NOT be called from interrupt context,
 915 * because the bus read/write functions may wait for an interrupt
 916 * to conclude the operation.
 917 */
 918int mdiobus_write(struct mii_bus *bus, int addr, u32 regnum, u16 val)
 919{
 920	int err;
 
 921
 922	mutex_lock(&bus->mdio_lock);
 923	err = __mdiobus_write(bus, addr, regnum, val);
 924	mutex_unlock(&bus->mdio_lock);
 925
 926	return err;
 927}
 928EXPORT_SYMBOL(mdiobus_write);
 929
 930/**
 931 * mdiobus_modify - Convenience function for modifying a given mdio device
 932 *	register
 933 * @bus: the mii_bus struct
 934 * @addr: the phy address
 935 * @regnum: register number to write
 936 * @mask: bit mask of bits to clear
 937 * @set: bit mask of bits to set
 938 */
 939int mdiobus_modify(struct mii_bus *bus, int addr, u32 regnum, u16 mask, u16 set)
 940{
 941	int err;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 942
 943	mutex_lock(&bus->mdio_lock);
 944	err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
 945	mutex_unlock(&bus->mdio_lock);
 
 
 
 
 946
 947	return err < 0 ? err : 0;
 948}
 949EXPORT_SYMBOL_GPL(mdiobus_modify);
 950
 951/**
 952 * mdiobus_modify_changed - Convenience function for modifying a given mdio
 953 *	device register and returning if it changed
 954 * @bus: the mii_bus struct
 955 * @addr: the phy address
 956 * @regnum: register number to write
 957 * @mask: bit mask of bits to clear
 958 * @set: bit mask of bits to set
 959 */
 960int mdiobus_modify_changed(struct mii_bus *bus, int addr, u32 regnum,
 961			   u16 mask, u16 set)
 962{
 963	int err;
 
 
 
 
 
 
 
 
 
 
 964
 965	mutex_lock(&bus->mdio_lock);
 966	err = __mdiobus_modify_changed(bus, addr, regnum, mask, set);
 967	mutex_unlock(&bus->mdio_lock);
 968
 969	return err;
 970}
 971EXPORT_SYMBOL_GPL(mdiobus_modify_changed);
 972
 973/**
 974 * mdio_bus_match - determine if given MDIO driver supports the given
 975 *		    MDIO device
 976 * @dev: target MDIO device
 977 * @drv: given MDIO driver
 978 *
 979 * Description: Given a MDIO device, and a MDIO driver, return 1 if
 980 *   the driver supports the device.  Otherwise, return 0. This may
 981 *   require calling the devices own match function, since different classes
 982 *   of MDIO devices have different match criteria.
 983 */
 984static int mdio_bus_match(struct device *dev, struct device_driver *drv)
 985{
 986	struct mdio_driver *mdiodrv = to_mdio_driver(drv);
 987	struct mdio_device *mdio = to_mdio_device(dev);
 
 988
 989	/* Both the driver and device must type-match */
 990	if (!(mdiodrv->mdiodrv.flags & MDIO_DEVICE_IS_PHY) !=
 991	    !(mdio->flags & MDIO_DEVICE_FLAG_PHY))
 992		return 0;
 993
 994	if (of_driver_match_device(dev, drv))
 995		return 1;
 
 996
 997	if (mdio->bus_match)
 998		return mdio->bus_match(dev, drv);
 
 999
1000	return 0;
1001}
1002
1003static int mdio_uevent(struct device *dev, struct kobj_uevent_env *env)
1004{
1005	int rc;
 
 
 
 
 
1006
1007	/* Some devices have extra OF data and an OF-style MODALIAS */
1008	rc = of_device_uevent_modalias(dev, env);
1009	if (rc != -ENODEV)
1010		return rc;
 
 
 
 
 
1011
1012	return 0;
1013}
1014
1015static struct attribute *mdio_bus_device_statistics_attrs[] = {
1016	&dev_attr_mdio_bus_device_transfers.attr.attr,
1017	&dev_attr_mdio_bus_device_errors.attr.attr,
1018	&dev_attr_mdio_bus_device_writes.attr.attr,
1019	&dev_attr_mdio_bus_device_reads.attr.attr,
1020	NULL,
1021};
1022
1023static const struct attribute_group mdio_bus_device_statistics_group = {
1024	.name	= "statistics",
1025	.attrs	= mdio_bus_device_statistics_attrs,
1026};
 
1027
1028static const struct attribute_group *mdio_bus_dev_groups[] = {
1029	&mdio_bus_device_statistics_group,
1030	NULL,
1031};
1032
1033struct bus_type mdio_bus_type = {
1034	.name		= "mdio_bus",
1035	.dev_groups	= mdio_bus_dev_groups,
1036	.match		= mdio_bus_match,
1037	.uevent		= mdio_uevent,
1038};
1039EXPORT_SYMBOL(mdio_bus_type);
1040
1041int __init mdio_bus_init(void)
1042{
1043	int ret;
1044
1045	ret = class_register(&mdio_bus_class);
1046	if (!ret) {
1047		ret = bus_register(&mdio_bus_type);
1048		if (ret)
1049			class_unregister(&mdio_bus_class);
1050	}
1051
1052	return ret;
1053}
1054
1055#if IS_ENABLED(CONFIG_PHYLIB)
1056void mdio_bus_exit(void)
1057{
1058	class_unregister(&mdio_bus_class);
1059	bus_unregister(&mdio_bus_type);
1060}
1061EXPORT_SYMBOL_GPL(mdio_bus_exit);
1062#else
1063module_init(mdio_bus_init);
1064/* no module_exit, intentional */
1065MODULE_LICENSE("GPL");
1066MODULE_DESCRIPTION("MDIO bus/device layer");
1067#endif