2 * drivers/net/phy/mdio_bus.c
8 * Copyright (c) 2004 Freescale Semiconductor, Inc.
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.
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>
30 #include <linux/module.h>
31 #include <linux/mii.h>
32 #include <linux/ethtool.h>
33 #include <linux/phy.h>
37 #include <asm/uaccess.h>
40 * mdiobus_alloc_size - allocate a mii_bus structure
41 * @size: extra amount of memory to allocate for private storage.
42 * If non-zero, then bus->priv is points to that memory.
44 * Description: called by a bus driver to allocate an mii_bus
45 * structure to fill in.
47 struct mii_bus
*mdiobus_alloc_size(size_t size
)
50 size_t aligned_size
= ALIGN(sizeof(*bus
), NETDEV_ALIGN
);
53 /* If we alloc extra space, it should be aligned */
55 alloc_size
= aligned_size
+ size
;
57 alloc_size
= sizeof(*bus
);
59 bus
= kzalloc(alloc_size
, GFP_KERNEL
);
61 bus
->state
= MDIOBUS_ALLOCATED
;
63 bus
->priv
= (void *)bus
+ aligned_size
;
68 EXPORT_SYMBOL(mdiobus_alloc_size
);
71 * mdiobus_release - mii_bus device release callback
72 * @d: the target struct device that contains the mii_bus
74 * Description: called when the last reference to an mii_bus is
75 * dropped, to free the underlying memory.
77 static void mdiobus_release(struct device
*d
)
79 struct mii_bus
*bus
= to_mii_bus(d
);
80 BUG_ON(bus
->state
!= MDIOBUS_RELEASED
&&
81 /* for compatibility with error handling in drivers */
82 bus
->state
!= MDIOBUS_ALLOCATED
);
86 static struct class mdio_bus_class
= {
88 .dev_release
= mdiobus_release
,
91 #if IS_ENABLED(CONFIG_OF_MDIO)
92 /* Helper function for of_mdio_find_bus */
93 static int of_mdio_bus_match(struct device
*dev
, void *mdio_bus_np
)
95 return dev
->of_node
== mdio_bus_np
;
98 * of_mdio_find_bus - Given an mii_bus node, find the mii_bus.
99 * @mdio_bus_np: Pointer to the mii_bus.
101 * Returns a pointer to the mii_bus, or NULL if none found.
103 * Because the association of a device_node and mii_bus is made via
104 * of_mdiobus_register(), the mii_bus cannot be found before it is
105 * registered with of_mdiobus_register().
108 struct mii_bus
*of_mdio_find_bus(struct device_node
*mdio_bus_np
)
115 d
= class_find_device(&mdio_bus_class
, NULL
, mdio_bus_np
,
118 return d
? to_mii_bus(d
) : NULL
;
120 EXPORT_SYMBOL(of_mdio_find_bus
);
124 * mdiobus_register - bring up all the PHYs on a given bus and attach them to bus
125 * @bus: target mii_bus
127 * Description: Called by a bus driver to bring up all the PHYs
128 * on a given bus, and attach them to the bus.
130 * Returns 0 on success or < 0 on error.
132 int mdiobus_register(struct mii_bus
*bus
)
136 if (NULL
== bus
|| NULL
== bus
->name
||
141 BUG_ON(bus
->state
!= MDIOBUS_ALLOCATED
&&
142 bus
->state
!= MDIOBUS_UNREGISTERED
);
144 bus
->dev
.parent
= bus
->parent
;
145 bus
->dev
.class = &mdio_bus_class
;
146 bus
->dev
.groups
= NULL
;
147 dev_set_name(&bus
->dev
, "%s", bus
->id
);
149 err
= device_register(&bus
->dev
);
151 printk(KERN_ERR
"mii_bus %s failed to register\n", bus
->id
);
155 mutex_init(&bus
->mdio_lock
);
160 for (i
= 0; i
< PHY_MAX_ADDR
; i
++) {
161 if ((bus
->phy_mask
& (1 << i
)) == 0) {
162 struct phy_device
*phydev
;
164 phydev
= mdiobus_scan(bus
, i
);
165 if (IS_ERR(phydev
)) {
166 err
= PTR_ERR(phydev
);
172 bus
->state
= MDIOBUS_REGISTERED
;
173 pr_info("%s: probed\n", bus
->name
);
179 device_unregister(&bus
->phy_map
[i
]->dev
);
181 device_del(&bus
->dev
);
184 EXPORT_SYMBOL(mdiobus_register
);
186 void mdiobus_unregister(struct mii_bus
*bus
)
190 BUG_ON(bus
->state
!= MDIOBUS_REGISTERED
);
191 bus
->state
= MDIOBUS_UNREGISTERED
;
193 device_del(&bus
->dev
);
194 for (i
= 0; i
< PHY_MAX_ADDR
; i
++) {
196 device_unregister(&bus
->phy_map
[i
]->dev
);
197 bus
->phy_map
[i
] = NULL
;
200 EXPORT_SYMBOL(mdiobus_unregister
);
203 * mdiobus_free - free a struct mii_bus
204 * @bus: mii_bus to free
206 * This function releases the reference to the underlying device
207 * object in the mii_bus. If this is the last reference, the mii_bus
210 void mdiobus_free(struct mii_bus
*bus
)
213 * For compatibility with error handling in drivers.
215 if (bus
->state
== MDIOBUS_ALLOCATED
) {
220 BUG_ON(bus
->state
!= MDIOBUS_UNREGISTERED
);
221 bus
->state
= MDIOBUS_RELEASED
;
223 put_device(&bus
->dev
);
225 EXPORT_SYMBOL(mdiobus_free
);
227 struct phy_device
*mdiobus_scan(struct mii_bus
*bus
, int addr
)
229 struct phy_device
*phydev
;
232 phydev
= get_phy_device(bus
, addr
);
233 if (IS_ERR(phydev
) || phydev
== NULL
)
236 err
= phy_device_register(phydev
);
238 phy_device_free(phydev
);
244 EXPORT_SYMBOL(mdiobus_scan
);
247 * mdiobus_read - Convenience function for reading a given MII mgmt register
248 * @bus: the mii_bus struct
249 * @addr: the phy address
250 * @regnum: register number to read
252 * NOTE: MUST NOT be called from interrupt context,
253 * because the bus read/write functions may wait for an interrupt
254 * to conclude the operation.
256 int mdiobus_read(struct mii_bus
*bus
, int addr
, u32 regnum
)
260 BUG_ON(in_interrupt());
262 mutex_lock(&bus
->mdio_lock
);
263 retval
= bus
->read(bus
, addr
, regnum
);
264 mutex_unlock(&bus
->mdio_lock
);
268 EXPORT_SYMBOL(mdiobus_read
);
271 * mdiobus_write - Convenience function for writing a given MII mgmt register
272 * @bus: the mii_bus struct
273 * @addr: the phy address
274 * @regnum: register number to write
275 * @val: value to write to @regnum
277 * NOTE: MUST NOT be called from interrupt context,
278 * because the bus read/write functions may wait for an interrupt
279 * to conclude the operation.
281 int mdiobus_write(struct mii_bus
*bus
, int addr
, u32 regnum
, u16 val
)
285 BUG_ON(in_interrupt());
287 mutex_lock(&bus
->mdio_lock
);
288 err
= bus
->write(bus
, addr
, regnum
, val
);
289 mutex_unlock(&bus
->mdio_lock
);
293 EXPORT_SYMBOL(mdiobus_write
);
296 * mdio_bus_match - determine if given PHY driver supports the given PHY device
297 * @dev: target PHY device
298 * @drv: given PHY driver
300 * Description: Given a PHY device, and a PHY driver, return 1 if
301 * the driver supports the device. Otherwise, return 0.
303 static int mdio_bus_match(struct device
*dev
, struct device_driver
*drv
)
305 struct phy_device
*phydev
= to_phy_device(dev
);
306 struct phy_driver
*phydrv
= to_phy_driver(drv
);
308 return ((phydrv
->phy_id
& phydrv
->phy_id_mask
) ==
309 (phydev
->phy_id
& phydrv
->phy_id_mask
));
314 static bool mdio_bus_phy_may_suspend(struct phy_device
*phydev
)
316 struct device_driver
*drv
= phydev
->dev
.driver
;
317 struct phy_driver
*phydrv
= to_phy_driver(drv
);
318 struct net_device
*netdev
= phydev
->attached_dev
;
320 if (!drv
|| !phydrv
->suspend
)
323 /* PHY not attached? May suspend. */
328 * Don't suspend PHY if the attched netdev parent may wakeup.
329 * The parent may point to a PCI device, as in tg3 driver.
331 if (netdev
->dev
.parent
&& device_may_wakeup(netdev
->dev
.parent
))
335 * Also don't suspend PHY if the netdev itself may wakeup. This
336 * is the case for devices w/o underlaying pwr. mgmt. aware bus,
339 if (device_may_wakeup(&netdev
->dev
))
345 static int mdio_bus_suspend(struct device
*dev
)
347 struct phy_driver
*phydrv
= to_phy_driver(dev
->driver
);
348 struct phy_device
*phydev
= to_phy_device(dev
);
351 * We must stop the state machine manually, otherwise it stops out of
352 * control, possibly with the phydev->lock held. Upon resume, netdev
353 * may call phy routines that try to grab the same lock, and that may
354 * lead to a deadlock.
356 if (phydev
->attached_dev
&& phydev
->adjust_link
)
357 phy_stop_machine(phydev
);
359 if (!mdio_bus_phy_may_suspend(phydev
))
362 return phydrv
->suspend(phydev
);
365 static int mdio_bus_resume(struct device
*dev
)
367 struct phy_driver
*phydrv
= to_phy_driver(dev
->driver
);
368 struct phy_device
*phydev
= to_phy_device(dev
);
371 if (!mdio_bus_phy_may_suspend(phydev
))
374 ret
= phydrv
->resume(phydev
);
379 if (phydev
->attached_dev
&& phydev
->adjust_link
)
380 phy_start_machine(phydev
, NULL
);
385 static int mdio_bus_restore(struct device
*dev
)
387 struct phy_device
*phydev
= to_phy_device(dev
);
388 struct net_device
*netdev
= phydev
->attached_dev
;
394 ret
= phy_init_hw(phydev
);
398 /* The PHY needs to renegotiate. */
400 phydev
->state
= PHY_UP
;
402 phy_start_machine(phydev
, NULL
);
407 static struct dev_pm_ops mdio_bus_pm_ops
= {
408 .suspend
= mdio_bus_suspend
,
409 .resume
= mdio_bus_resume
,
410 .freeze
= mdio_bus_suspend
,
411 .thaw
= mdio_bus_resume
,
412 .restore
= mdio_bus_restore
,
415 #define MDIO_BUS_PM_OPS (&mdio_bus_pm_ops)
419 #define MDIO_BUS_PM_OPS NULL
421 #endif /* CONFIG_PM */
423 struct bus_type mdio_bus_type
= {
425 .match
= mdio_bus_match
,
426 .pm
= MDIO_BUS_PM_OPS
,
428 EXPORT_SYMBOL(mdio_bus_type
);
430 int __init
mdio_bus_init(void)
434 ret
= class_register(&mdio_bus_class
);
436 ret
= bus_register(&mdio_bus_type
);
438 class_unregister(&mdio_bus_class
);
444 void mdio_bus_exit(void)
446 class_unregister(&mdio_bus_class
);
447 bus_unregister(&mdio_bus_type
);