xref: /linux/drivers/net/phy/phy.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
1 /*
2  * drivers/net/phy/phy.c
3  *
4  * Framework for configuring and reading PHY devices
5  * Based on code in sungem_phy.c and gianfar_phy.c
6  *
7  * Author: Andy Fleming
8  *
9  * Copyright (c) 2004 Freescale Semiconductor, Inc.
10  *
11  * This program is free software; you can redistribute  it and/or modify it
12  * under  the terms of  the GNU General  Public License as published by the
13  * Free Software Foundation;  either version 2 of the  License, or (at your
14  * option) any later version.
15  *
16  */
17 #include <linux/config.h>
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/unistd.h>
23 #include <linux/slab.h>
24 #include <linux/interrupt.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/netdevice.h>
28 #include <linux/etherdevice.h>
29 #include <linux/skbuff.h>
30 #include <linux/spinlock.h>
31 #include <linux/mm.h>
32 #include <linux/module.h>
33 #include <linux/version.h>
34 #include <linux/mii.h>
35 #include <linux/ethtool.h>
36 #include <linux/phy.h>
37 
38 #include <asm/io.h>
39 #include <asm/irq.h>
40 #include <asm/uaccess.h>
41 
42 /* Convenience function to print out the current phy status
43  */
44 void phy_print_status(struct phy_device *phydev)
45 {
46 	pr_info("%s: Link is %s", phydev->dev.bus_id,
47 			phydev->link ? "Up" : "Down");
48 	if (phydev->link)
49 		printk(" - %d/%s", phydev->speed,
50 				DUPLEX_FULL == phydev->duplex ?
51 				"Full" : "Half");
52 
53 	printk("\n");
54 }
55 EXPORT_SYMBOL(phy_print_status);
56 
57 
58 /* Convenience functions for reading/writing a given PHY
59  * register. They MUST NOT be called from interrupt context,
60  * because the bus read/write functions may wait for an interrupt
61  * to conclude the operation. */
62 int phy_read(struct phy_device *phydev, u16 regnum)
63 {
64 	int retval;
65 	struct mii_bus *bus = phydev->bus;
66 
67 	spin_lock_bh(&bus->mdio_lock);
68 	retval = bus->read(bus, phydev->addr, regnum);
69 	spin_unlock_bh(&bus->mdio_lock);
70 
71 	return retval;
72 }
73 EXPORT_SYMBOL(phy_read);
74 
75 int phy_write(struct phy_device *phydev, u16 regnum, u16 val)
76 {
77 	int err;
78 	struct mii_bus *bus = phydev->bus;
79 
80 	spin_lock_bh(&bus->mdio_lock);
81 	err = bus->write(bus, phydev->addr, regnum, val);
82 	spin_unlock_bh(&bus->mdio_lock);
83 
84 	return err;
85 }
86 EXPORT_SYMBOL(phy_write);
87 
88 
89 int phy_clear_interrupt(struct phy_device *phydev)
90 {
91 	int err = 0;
92 
93 	if (phydev->drv->ack_interrupt)
94 		err = phydev->drv->ack_interrupt(phydev);
95 
96 	return err;
97 }
98 
99 
100 int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
101 {
102 	int err = 0;
103 
104 	phydev->interrupts = interrupts;
105 	if (phydev->drv->config_intr)
106 		err = phydev->drv->config_intr(phydev);
107 
108 	return err;
109 }
110 
111 
112 /* phy_aneg_done
113  *
114  * description: Reads the status register and returns 0 either if
115  *   auto-negotiation is incomplete, or if there was an error.
116  *   Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
117  */
118 static inline int phy_aneg_done(struct phy_device *phydev)
119 {
120 	int retval;
121 
122 	retval = phy_read(phydev, MII_BMSR);
123 
124 	return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
125 }
126 
127 /* A structure for mapping a particular speed and duplex
128  * combination to a particular SUPPORTED and ADVERTISED value */
129 struct phy_setting {
130 	int speed;
131 	int duplex;
132 	u32 setting;
133 };
134 
135 /* A mapping of all SUPPORTED settings to speed/duplex */
136 static struct phy_setting settings[] = {
137 	{
138 		.speed = 10000,
139 		.duplex = DUPLEX_FULL,
140 		.setting = SUPPORTED_10000baseT_Full,
141 	},
142 	{
143 		.speed = SPEED_1000,
144 		.duplex = DUPLEX_FULL,
145 		.setting = SUPPORTED_1000baseT_Full,
146 	},
147 	{
148 		.speed = SPEED_1000,
149 		.duplex = DUPLEX_HALF,
150 		.setting = SUPPORTED_1000baseT_Half,
151 	},
152 	{
153 		.speed = SPEED_100,
154 		.duplex = DUPLEX_FULL,
155 		.setting = SUPPORTED_100baseT_Full,
156 	},
157 	{
158 		.speed = SPEED_100,
159 		.duplex = DUPLEX_HALF,
160 		.setting = SUPPORTED_100baseT_Half,
161 	},
162 	{
163 		.speed = SPEED_10,
164 		.duplex = DUPLEX_FULL,
165 		.setting = SUPPORTED_10baseT_Full,
166 	},
167 	{
168 		.speed = SPEED_10,
169 		.duplex = DUPLEX_HALF,
170 		.setting = SUPPORTED_10baseT_Half,
171 	},
172 };
173 
174 #define MAX_NUM_SETTINGS (sizeof(settings)/sizeof(struct phy_setting))
175 
176 /* phy_find_setting
177  *
178  * description: Searches the settings array for the setting which
179  *   matches the desired speed and duplex, and returns the index
180  *   of that setting.  Returns the index of the last setting if
181  *   none of the others match.
182  */
183 static inline int phy_find_setting(int speed, int duplex)
184 {
185 	int idx = 0;
186 
187 	while (idx < ARRAY_SIZE(settings) &&
188 			(settings[idx].speed != speed ||
189 			settings[idx].duplex != duplex))
190 		idx++;
191 
192 	return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
193 }
194 
195 /* phy_find_valid
196  * idx: The first index in settings[] to search
197  * features: A mask of the valid settings
198  *
199  * description: Returns the index of the first valid setting less
200  *   than or equal to the one pointed to by idx, as determined by
201  *   the mask in features.  Returns the index of the last setting
202  *   if nothing else matches.
203  */
204 static inline int phy_find_valid(int idx, u32 features)
205 {
206 	while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
207 		idx++;
208 
209 	return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
210 }
211 
212 /* phy_sanitize_settings
213  *
214  * description: Make sure the PHY is set to supported speeds and
215  *   duplexes.  Drop down by one in this order:  1000/FULL,
216  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF
217  */
218 void phy_sanitize_settings(struct phy_device *phydev)
219 {
220 	u32 features = phydev->supported;
221 	int idx;
222 
223 	/* Sanitize settings based on PHY capabilities */
224 	if ((features & SUPPORTED_Autoneg) == 0)
225 		phydev->autoneg = 0;
226 
227 	idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
228 			features);
229 
230 	phydev->speed = settings[idx].speed;
231 	phydev->duplex = settings[idx].duplex;
232 }
233 EXPORT_SYMBOL(phy_sanitize_settings);
234 
235 /* phy_ethtool_sset:
236  * A generic ethtool sset function.  Handles all the details
237  *
238  * A few notes about parameter checking:
239  * - We don't set port or transceiver, so we don't care what they
240  *   were set to.
241  * - phy_start_aneg() will make sure forced settings are sane, and
242  *   choose the next best ones from the ones selected, so we don't
243  *   care if ethtool tries to give us bad values
244  *
245  */
246 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
247 {
248 	if (cmd->phy_address != phydev->addr)
249 		return -EINVAL;
250 
251 	/* We make sure that we don't pass unsupported
252 	 * values in to the PHY */
253 	cmd->advertising &= phydev->supported;
254 
255 	/* Verify the settings we care about. */
256 	if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
257 		return -EINVAL;
258 
259 	if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
260 		return -EINVAL;
261 
262 	if (cmd->autoneg == AUTONEG_DISABLE
263 			&& ((cmd->speed != SPEED_1000
264 					&& cmd->speed != SPEED_100
265 					&& cmd->speed != SPEED_10)
266 				|| (cmd->duplex != DUPLEX_HALF
267 					&& cmd->duplex != DUPLEX_FULL)))
268 		return -EINVAL;
269 
270 	phydev->autoneg = cmd->autoneg;
271 
272 	phydev->speed = cmd->speed;
273 
274 	phydev->advertising = cmd->advertising;
275 
276 	if (AUTONEG_ENABLE == cmd->autoneg)
277 		phydev->advertising |= ADVERTISED_Autoneg;
278 	else
279 		phydev->advertising &= ~ADVERTISED_Autoneg;
280 
281 	phydev->duplex = cmd->duplex;
282 
283 	/* Restart the PHY */
284 	phy_start_aneg(phydev);
285 
286 	return 0;
287 }
288 
289 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
290 {
291 	cmd->supported = phydev->supported;
292 
293 	cmd->advertising = phydev->advertising;
294 
295 	cmd->speed = phydev->speed;
296 	cmd->duplex = phydev->duplex;
297 	cmd->port = PORT_MII;
298 	cmd->phy_address = phydev->addr;
299 	cmd->transceiver = XCVR_EXTERNAL;
300 	cmd->autoneg = phydev->autoneg;
301 
302 	return 0;
303 }
304 
305 
306 /* Note that this function is currently incompatible with the
307  * PHYCONTROL layer.  It changes registers without regard to
308  * current state.  Use at own risk
309  */
310 int phy_mii_ioctl(struct phy_device *phydev,
311 		struct mii_ioctl_data *mii_data, int cmd)
312 {
313 	u16 val = mii_data->val_in;
314 
315 	switch (cmd) {
316 	case SIOCGMIIPHY:
317 		mii_data->phy_id = phydev->addr;
318 		break;
319 	case SIOCGMIIREG:
320 		mii_data->val_out = phy_read(phydev, mii_data->reg_num);
321 		break;
322 
323 	case SIOCSMIIREG:
324 		if (!capable(CAP_NET_ADMIN))
325 			return -EPERM;
326 
327 		if (mii_data->phy_id == phydev->addr) {
328 			switch(mii_data->reg_num) {
329 			case MII_BMCR:
330 				if (val & (BMCR_RESET|BMCR_ANENABLE))
331 					phydev->autoneg = AUTONEG_DISABLE;
332 				else
333 					phydev->autoneg = AUTONEG_ENABLE;
334 				if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
335 					phydev->duplex = DUPLEX_FULL;
336 				else
337 					phydev->duplex = DUPLEX_HALF;
338 				break;
339 			case MII_ADVERTISE:
340 				phydev->advertising = val;
341 				break;
342 			default:
343 				/* do nothing */
344 				break;
345 			}
346 		}
347 
348 		phy_write(phydev, mii_data->reg_num, val);
349 
350 		if (mii_data->reg_num == MII_BMCR
351 				&& val & BMCR_RESET
352 				&& phydev->drv->config_init)
353 			phydev->drv->config_init(phydev);
354 		break;
355 	}
356 
357 	return 0;
358 }
359 
360 /* phy_start_aneg
361  *
362  * description: Sanitizes the settings (if we're not
363  *   autonegotiating them), and then calls the driver's
364  *   config_aneg function.  If the PHYCONTROL Layer is operating,
365  *   we change the state to reflect the beginning of
366  *   Auto-negotiation or forcing.
367  */
368 int phy_start_aneg(struct phy_device *phydev)
369 {
370 	int err;
371 
372 	spin_lock(&phydev->lock);
373 
374 	if (AUTONEG_DISABLE == phydev->autoneg)
375 		phy_sanitize_settings(phydev);
376 
377 	err = phydev->drv->config_aneg(phydev);
378 
379 	if (err < 0)
380 		goto out_unlock;
381 
382 	if (phydev->state != PHY_HALTED) {
383 		if (AUTONEG_ENABLE == phydev->autoneg) {
384 			phydev->state = PHY_AN;
385 			phydev->link_timeout = PHY_AN_TIMEOUT;
386 		} else {
387 			phydev->state = PHY_FORCING;
388 			phydev->link_timeout = PHY_FORCE_TIMEOUT;
389 		}
390 	}
391 
392 out_unlock:
393 	spin_unlock(&phydev->lock);
394 	return err;
395 }
396 EXPORT_SYMBOL(phy_start_aneg);
397 
398 
399 static void phy_change(void *data);
400 static void phy_timer(unsigned long data);
401 
402 /* phy_start_machine:
403  *
404  * description: The PHY infrastructure can run a state machine
405  *   which tracks whether the PHY is starting up, negotiating,
406  *   etc.  This function starts the timer which tracks the state
407  *   of the PHY.  If you want to be notified when the state
408  *   changes, pass in the callback, otherwise, pass NULL.  If you
409  *   want to maintain your own state machine, do not call this
410  *   function. */
411 void phy_start_machine(struct phy_device *phydev,
412 		void (*handler)(struct net_device *))
413 {
414 	phydev->adjust_state = handler;
415 
416 	init_timer(&phydev->phy_timer);
417 	phydev->phy_timer.function = &phy_timer;
418 	phydev->phy_timer.data = (unsigned long) phydev;
419 	mod_timer(&phydev->phy_timer, jiffies + HZ);
420 }
421 
422 /* phy_stop_machine
423  *
424  * description: Stops the state machine timer, sets the state to
425  *   UP (unless it wasn't up yet), and then frees the interrupt,
426  *   if it is in use. This function must be called BEFORE
427  *   phy_detach.
428  */
429 void phy_stop_machine(struct phy_device *phydev)
430 {
431 	del_timer_sync(&phydev->phy_timer);
432 
433 	spin_lock(&phydev->lock);
434 	if (phydev->state > PHY_UP)
435 		phydev->state = PHY_UP;
436 	spin_unlock(&phydev->lock);
437 
438 	if (phydev->irq != PHY_POLL)
439 		phy_stop_interrupts(phydev);
440 
441 	phydev->adjust_state = NULL;
442 }
443 
444 /* phy_force_reduction
445  *
446  * description: Reduces the speed/duplex settings by
447  *   one notch.  The order is so:
448  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF,
449  *   10/FULL, 10/HALF.  The function bottoms out at 10/HALF.
450  */
451 static void phy_force_reduction(struct phy_device *phydev)
452 {
453 	int idx;
454 
455 	idx = phy_find_setting(phydev->speed, phydev->duplex);
456 
457 	idx++;
458 
459 	idx = phy_find_valid(idx, phydev->supported);
460 
461 	phydev->speed = settings[idx].speed;
462 	phydev->duplex = settings[idx].duplex;
463 
464 	pr_info("Trying %d/%s\n", phydev->speed,
465 			DUPLEX_FULL == phydev->duplex ?
466 			"FULL" : "HALF");
467 }
468 
469 
470 /* phy_error:
471  *
472  * Moves the PHY to the HALTED state in response to a read
473  * or write error, and tells the controller the link is down.
474  * Must not be called from interrupt context, or while the
475  * phydev->lock is held.
476  */
477 void phy_error(struct phy_device *phydev)
478 {
479 	spin_lock(&phydev->lock);
480 	phydev->state = PHY_HALTED;
481 	spin_unlock(&phydev->lock);
482 }
483 
484 /* phy_interrupt
485  *
486  * description: When a PHY interrupt occurs, the handler disables
487  * interrupts, and schedules a work task to clear the interrupt.
488  */
489 static irqreturn_t phy_interrupt(int irq, void *phy_dat, struct pt_regs *regs)
490 {
491 	struct phy_device *phydev = phy_dat;
492 
493 	/* The MDIO bus is not allowed to be written in interrupt
494 	 * context, so we need to disable the irq here.  A work
495 	 * queue will write the PHY to disable and clear the
496 	 * interrupt, and then reenable the irq line. */
497 	disable_irq_nosync(irq);
498 
499 	schedule_work(&phydev->phy_queue);
500 
501 	return IRQ_HANDLED;
502 }
503 
504 /* Enable the interrupts from the PHY side */
505 int phy_enable_interrupts(struct phy_device *phydev)
506 {
507 	int err;
508 
509 	err = phy_clear_interrupt(phydev);
510 
511 	if (err < 0)
512 		return err;
513 
514 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
515 
516 	return err;
517 }
518 EXPORT_SYMBOL(phy_enable_interrupts);
519 
520 /* Disable the PHY interrupts from the PHY side */
521 int phy_disable_interrupts(struct phy_device *phydev)
522 {
523 	int err;
524 
525 	/* Disable PHY interrupts */
526 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
527 
528 	if (err)
529 		goto phy_err;
530 
531 	/* Clear the interrupt */
532 	err = phy_clear_interrupt(phydev);
533 
534 	if (err)
535 		goto phy_err;
536 
537 	return 0;
538 
539 phy_err:
540 	phy_error(phydev);
541 
542 	return err;
543 }
544 EXPORT_SYMBOL(phy_disable_interrupts);
545 
546 /* phy_start_interrupts
547  *
548  * description: Request the interrupt for the given PHY.  If
549  *   this fails, then we set irq to PHY_POLL.
550  *   Otherwise, we enable the interrupts in the PHY.
551  *   Returns 0 on success.
552  *   This should only be called with a valid IRQ number.
553  */
554 int phy_start_interrupts(struct phy_device *phydev)
555 {
556 	int err = 0;
557 
558 	INIT_WORK(&phydev->phy_queue, phy_change, phydev);
559 
560 	if (request_irq(phydev->irq, phy_interrupt,
561 				SA_SHIRQ,
562 				"phy_interrupt",
563 				phydev) < 0) {
564 		printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
565 				phydev->bus->name,
566 				phydev->irq);
567 		phydev->irq = PHY_POLL;
568 		return 0;
569 	}
570 
571 	err = phy_enable_interrupts(phydev);
572 
573 	return err;
574 }
575 EXPORT_SYMBOL(phy_start_interrupts);
576 
577 int phy_stop_interrupts(struct phy_device *phydev)
578 {
579 	int err;
580 
581 	err = phy_disable_interrupts(phydev);
582 
583 	if (err)
584 		phy_error(phydev);
585 
586 	free_irq(phydev->irq, phydev);
587 
588 	return err;
589 }
590 EXPORT_SYMBOL(phy_stop_interrupts);
591 
592 
593 /* Scheduled by the phy_interrupt/timer to handle PHY changes */
594 static void phy_change(void *data)
595 {
596 	int err;
597 	struct phy_device *phydev = data;
598 
599 	err = phy_disable_interrupts(phydev);
600 
601 	if (err)
602 		goto phy_err;
603 
604 	spin_lock(&phydev->lock);
605 	if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
606 		phydev->state = PHY_CHANGELINK;
607 	spin_unlock(&phydev->lock);
608 
609 	enable_irq(phydev->irq);
610 
611 	/* Reenable interrupts */
612 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
613 
614 	if (err)
615 		goto irq_enable_err;
616 
617 	return;
618 
619 irq_enable_err:
620 	disable_irq(phydev->irq);
621 phy_err:
622 	phy_error(phydev);
623 }
624 
625 /* Bring down the PHY link, and stop checking the status. */
626 void phy_stop(struct phy_device *phydev)
627 {
628 	spin_lock(&phydev->lock);
629 
630 	if (PHY_HALTED == phydev->state)
631 		goto out_unlock;
632 
633 	if (phydev->irq != PHY_POLL) {
634 		/* Clear any pending interrupts */
635 		phy_clear_interrupt(phydev);
636 
637 		/* Disable PHY Interrupts */
638 		phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
639 	}
640 
641 	phydev->state = PHY_HALTED;
642 
643 out_unlock:
644 	spin_unlock(&phydev->lock);
645 }
646 
647 
648 /* phy_start
649  *
650  * description: Indicates the attached device's readiness to
651  *   handle PHY-related work.  Used during startup to start the
652  *   PHY, and after a call to phy_stop() to resume operation.
653  *   Also used to indicate the MDIO bus has cleared an error
654  *   condition.
655  */
656 void phy_start(struct phy_device *phydev)
657 {
658 	spin_lock(&phydev->lock);
659 
660 	switch (phydev->state) {
661 		case PHY_STARTING:
662 			phydev->state = PHY_PENDING;
663 			break;
664 		case PHY_READY:
665 			phydev->state = PHY_UP;
666 			break;
667 		case PHY_HALTED:
668 			phydev->state = PHY_RESUMING;
669 		default:
670 			break;
671 	}
672 	spin_unlock(&phydev->lock);
673 }
674 EXPORT_SYMBOL(phy_stop);
675 EXPORT_SYMBOL(phy_start);
676 
677 /* PHY timer which handles the state machine */
678 static void phy_timer(unsigned long data)
679 {
680 	struct phy_device *phydev = (struct phy_device *)data;
681 	int needs_aneg = 0;
682 	int err = 0;
683 
684 	spin_lock(&phydev->lock);
685 
686 	if (phydev->adjust_state)
687 		phydev->adjust_state(phydev->attached_dev);
688 
689 	switch(phydev->state) {
690 		case PHY_DOWN:
691 		case PHY_STARTING:
692 		case PHY_READY:
693 		case PHY_PENDING:
694 			break;
695 		case PHY_UP:
696 			needs_aneg = 1;
697 
698 			phydev->link_timeout = PHY_AN_TIMEOUT;
699 
700 			break;
701 		case PHY_AN:
702 			/* Check if negotiation is done.  Break
703 			 * if there's an error */
704 			err = phy_aneg_done(phydev);
705 			if (err < 0)
706 				break;
707 
708 			/* If auto-negotiation is done, we change to
709 			 * either RUNNING, or NOLINK */
710 			if (err > 0) {
711 				err = phy_read_status(phydev);
712 
713 				if (err)
714 					break;
715 
716 				if (phydev->link) {
717 					phydev->state = PHY_RUNNING;
718 					netif_carrier_on(phydev->attached_dev);
719 				} else {
720 					phydev->state = PHY_NOLINK;
721 					netif_carrier_off(phydev->attached_dev);
722 				}
723 
724 				phydev->adjust_link(phydev->attached_dev);
725 
726 			} else if (0 == phydev->link_timeout--) {
727 				/* The counter expired, so either we
728 				 * switch to forced mode, or the
729 				 * magic_aneg bit exists, and we try aneg
730 				 * again */
731 				if (!(phydev->drv->flags & PHY_HAS_MAGICANEG)) {
732 					int idx;
733 
734 					/* We'll start from the
735 					 * fastest speed, and work
736 					 * our way down */
737 					idx = phy_find_valid(0,
738 							phydev->supported);
739 
740 					phydev->speed = settings[idx].speed;
741 					phydev->duplex = settings[idx].duplex;
742 
743 					phydev->autoneg = AUTONEG_DISABLE;
744 					phydev->state = PHY_FORCING;
745 					phydev->link_timeout =
746 						PHY_FORCE_TIMEOUT;
747 
748 					pr_info("Trying %d/%s\n",
749 							phydev->speed,
750 							DUPLEX_FULL ==
751 							phydev->duplex ?
752 							"FULL" : "HALF");
753 				}
754 
755 				needs_aneg = 1;
756 			}
757 			break;
758 		case PHY_NOLINK:
759 			err = phy_read_status(phydev);
760 
761 			if (err)
762 				break;
763 
764 			if (phydev->link) {
765 				phydev->state = PHY_RUNNING;
766 				netif_carrier_on(phydev->attached_dev);
767 				phydev->adjust_link(phydev->attached_dev);
768 			}
769 			break;
770 		case PHY_FORCING:
771 			err = phy_read_status(phydev);
772 
773 			if (err)
774 				break;
775 
776 			if (phydev->link) {
777 				phydev->state = PHY_RUNNING;
778 				netif_carrier_on(phydev->attached_dev);
779 			} else {
780 				if (0 == phydev->link_timeout--) {
781 					phy_force_reduction(phydev);
782 					needs_aneg = 1;
783 				}
784 			}
785 
786 			phydev->adjust_link(phydev->attached_dev);
787 			break;
788 		case PHY_RUNNING:
789 			/* Only register a CHANGE if we are
790 			 * polling */
791 			if (PHY_POLL == phydev->irq)
792 				phydev->state = PHY_CHANGELINK;
793 			break;
794 		case PHY_CHANGELINK:
795 			err = phy_read_status(phydev);
796 
797 			if (err)
798 				break;
799 
800 			if (phydev->link) {
801 				phydev->state = PHY_RUNNING;
802 				netif_carrier_on(phydev->attached_dev);
803 			} else {
804 				phydev->state = PHY_NOLINK;
805 				netif_carrier_off(phydev->attached_dev);
806 			}
807 
808 			phydev->adjust_link(phydev->attached_dev);
809 
810 			if (PHY_POLL != phydev->irq)
811 				err = phy_config_interrupt(phydev,
812 						PHY_INTERRUPT_ENABLED);
813 			break;
814 		case PHY_HALTED:
815 			if (phydev->link) {
816 				phydev->link = 0;
817 				netif_carrier_off(phydev->attached_dev);
818 				phydev->adjust_link(phydev->attached_dev);
819 			}
820 			break;
821 		case PHY_RESUMING:
822 
823 			err = phy_clear_interrupt(phydev);
824 
825 			if (err)
826 				break;
827 
828 			err = phy_config_interrupt(phydev,
829 					PHY_INTERRUPT_ENABLED);
830 
831 			if (err)
832 				break;
833 
834 			if (AUTONEG_ENABLE == phydev->autoneg) {
835 				err = phy_aneg_done(phydev);
836 				if (err < 0)
837 					break;
838 
839 				/* err > 0 if AN is done.
840 				 * Otherwise, it's 0, and we're
841 				 * still waiting for AN */
842 				if (err > 0) {
843 					phydev->state = PHY_RUNNING;
844 				} else {
845 					phydev->state = PHY_AN;
846 					phydev->link_timeout = PHY_AN_TIMEOUT;
847 				}
848 			} else
849 				phydev->state = PHY_RUNNING;
850 			break;
851 	}
852 
853 	spin_unlock(&phydev->lock);
854 
855 	if (needs_aneg)
856 		err = phy_start_aneg(phydev);
857 
858 	if (err < 0)
859 		phy_error(phydev);
860 
861 	mod_timer(&phydev->phy_timer, jiffies + PHY_STATE_TIME * HZ);
862 }
863 
864