Merge branch 'master'
[pandora-kernel.git] / drivers / net / phy / phy.c
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