e323efd4ed18dda72f1903ed36cb7058b891e558
[linux-2.6.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  * Copyright (c) 2006  Maciej W. Rozycki
11  *
12  * This program is free software; you can redistribute  it and/or modify it
13  * under  the terms of  the GNU General  Public License as published by the
14  * Free Software Foundation;  either version 2 of the  License, or (at your
15  * option) any later version.
16  *
17  */
18 #include <linux/kernel.h>
19 #include <linux/string.h>
20 #include <linux/errno.h>
21 #include <linux/unistd.h>
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/init.h>
25 #include <linux/delay.h>
26 #include <linux/netdevice.h>
27 #include <linux/etherdevice.h>
28 #include <linux/skbuff.h>
29 #include <linux/spinlock.h>
30 #include <linux/mm.h>
31 #include <linux/module.h>
32 #include <linux/mii.h>
33 #include <linux/ethtool.h>
34 #include <linux/phy.h>
35 #include <linux/timer.h>
36 #include <linux/workqueue.h>
37
38 #include <asm/io.h>
39 #include <asm/irq.h>
40 #include <asm/uaccess.h>
41
42 /**
43  * phy_print_status - Convenience function to print out the current phy status
44  * @phydev: the phy_device struct
45  */
46 void phy_print_status(struct phy_device *phydev)
47 {
48         pr_info("PHY: %s - Link is %s", phydev->dev.bus_id,
49                         phydev->link ? "Up" : "Down");
50         if (phydev->link)
51                 printk(" - %d/%s", phydev->speed,
52                                 DUPLEX_FULL == phydev->duplex ?
53                                 "Full" : "Half");
54
55         printk("\n");
56 }
57 EXPORT_SYMBOL(phy_print_status);
58
59
60 /**
61  * phy_read - Convenience function for reading a given PHY register
62  * @phydev: the phy_device struct
63  * @regnum: register number to read
64  *
65  * NOTE: MUST NOT be called from interrupt context,
66  * because the bus read/write functions may wait for an interrupt
67  * to conclude the operation.
68  */
69 int phy_read(struct phy_device *phydev, u16 regnum)
70 {
71         int retval;
72         struct mii_bus *bus = phydev->bus;
73
74         spin_lock_bh(&bus->mdio_lock);
75         retval = bus->read(bus, phydev->addr, regnum);
76         spin_unlock_bh(&bus->mdio_lock);
77
78         return retval;
79 }
80 EXPORT_SYMBOL(phy_read);
81
82 /**
83  * phy_write - Convenience function for writing a given PHY register
84  * @phydev: the phy_device struct
85  * @regnum: register number to write
86  * @val: value to write to @regnum
87  *
88  * NOTE: MUST NOT be called from interrupt context,
89  * because the bus read/write functions may wait for an interrupt
90  * to conclude the operation.
91  */
92 int phy_write(struct phy_device *phydev, u16 regnum, u16 val)
93 {
94         int err;
95         struct mii_bus *bus = phydev->bus;
96
97         spin_lock_bh(&bus->mdio_lock);
98         err = bus->write(bus, phydev->addr, regnum, val);
99         spin_unlock_bh(&bus->mdio_lock);
100
101         return err;
102 }
103 EXPORT_SYMBOL(phy_write);
104
105 /**
106  * phy_clear_interrupt - Ack the phy device's interrupt
107  * @phydev: the phy_device struct
108  *
109  * If the @phydev driver has an ack_interrupt function, call it to
110  * ack and clear the phy device's interrupt.
111  *
112  * Returns 0 on success on < 0 on error.
113  */
114 int phy_clear_interrupt(struct phy_device *phydev)
115 {
116         int err = 0;
117
118         if (phydev->drv->ack_interrupt)
119                 err = phydev->drv->ack_interrupt(phydev);
120
121         return err;
122 }
123
124 /**
125  * phy_config_interrupt - configure the PHY device for the requested interrupts
126  * @phydev: the phy_device struct
127  * @interrupts: interrupt flags to configure for this @phydev
128  *
129  * Returns 0 on success on < 0 on error.
130  */
131 int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
132 {
133         int err = 0;
134
135         phydev->interrupts = interrupts;
136         if (phydev->drv->config_intr)
137                 err = phydev->drv->config_intr(phydev);
138
139         return err;
140 }
141
142
143 /**
144  * phy_aneg_done - return auto-negotiation status
145  * @phydev: target phy_device struct
146  *
147  * Description: Reads the status register and returns 0 either if
148  *   auto-negotiation is incomplete, or if there was an error.
149  *   Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
150  */
151 static inline int phy_aneg_done(struct phy_device *phydev)
152 {
153         int retval;
154
155         retval = phy_read(phydev, MII_BMSR);
156
157         return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
158 }
159
160 /* A structure for mapping a particular speed and duplex
161  * combination to a particular SUPPORTED and ADVERTISED value */
162 struct phy_setting {
163         int speed;
164         int duplex;
165         u32 setting;
166 };
167
168 /* A mapping of all SUPPORTED settings to speed/duplex */
169 static const struct phy_setting settings[] = {
170         {
171                 .speed = 10000,
172                 .duplex = DUPLEX_FULL,
173                 .setting = SUPPORTED_10000baseT_Full,
174         },
175         {
176                 .speed = SPEED_1000,
177                 .duplex = DUPLEX_FULL,
178                 .setting = SUPPORTED_1000baseT_Full,
179         },
180         {
181                 .speed = SPEED_1000,
182                 .duplex = DUPLEX_HALF,
183                 .setting = SUPPORTED_1000baseT_Half,
184         },
185         {
186                 .speed = SPEED_100,
187                 .duplex = DUPLEX_FULL,
188                 .setting = SUPPORTED_100baseT_Full,
189         },
190         {
191                 .speed = SPEED_100,
192                 .duplex = DUPLEX_HALF,
193                 .setting = SUPPORTED_100baseT_Half,
194         },
195         {
196                 .speed = SPEED_10,
197                 .duplex = DUPLEX_FULL,
198                 .setting = SUPPORTED_10baseT_Full,
199         },
200         {
201                 .speed = SPEED_10,
202                 .duplex = DUPLEX_HALF,
203                 .setting = SUPPORTED_10baseT_Half,
204         },
205 };
206
207 #define MAX_NUM_SETTINGS (sizeof(settings)/sizeof(struct phy_setting))
208
209 /**
210  * phy_find_setting - find a PHY settings array entry that matches speed & duplex
211  * @speed: speed to match
212  * @duplex: duplex to match
213  *
214  * Description: Searches the settings array for the setting which
215  *   matches the desired speed and duplex, and returns the index
216  *   of that setting.  Returns the index of the last setting if
217  *   none of the others match.
218  */
219 static inline int phy_find_setting(int speed, int duplex)
220 {
221         int idx = 0;
222
223         while (idx < ARRAY_SIZE(settings) &&
224                         (settings[idx].speed != speed ||
225                         settings[idx].duplex != duplex))
226                 idx++;
227
228         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
229 }
230
231 /**
232  * phy_find_valid - find a PHY setting that matches the requested features mask
233  * @idx: The first index in settings[] to search
234  * @features: A mask of the valid settings
235  *
236  * Description: Returns the index of the first valid setting less
237  *   than or equal to the one pointed to by idx, as determined by
238  *   the mask in features.  Returns the index of the last setting
239  *   if nothing else matches.
240  */
241 static inline int phy_find_valid(int idx, u32 features)
242 {
243         while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
244                 idx++;
245
246         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
247 }
248
249 /**
250  * phy_sanitize_settings - make sure the PHY is set to supported speed and duplex
251  * @phydev: the target phy_device struct
252  *
253  * Description: Make sure the PHY is set to supported speeds and
254  *   duplexes.  Drop down by one in this order:  1000/FULL,
255  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
256  */
257 void phy_sanitize_settings(struct phy_device *phydev)
258 {
259         u32 features = phydev->supported;
260         int idx;
261
262         /* Sanitize settings based on PHY capabilities */
263         if ((features & SUPPORTED_Autoneg) == 0)
264                 phydev->autoneg = AUTONEG_DISABLE;
265
266         idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
267                         features);
268
269         phydev->speed = settings[idx].speed;
270         phydev->duplex = settings[idx].duplex;
271 }
272 EXPORT_SYMBOL(phy_sanitize_settings);
273
274 /**
275  * phy_ethtool_sset - generic ethtool sset function, handles all the details
276  * @phydev: target phy_device struct
277  * @cmd: ethtool_cmd
278  *
279  * A few notes about parameter checking:
280  * - We don't set port or transceiver, so we don't care what they
281  *   were set to.
282  * - phy_start_aneg() will make sure forced settings are sane, and
283  *   choose the next best ones from the ones selected, so we don't
284  *   care if ethtool tries to give us bad values.
285  */
286 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
287 {
288         if (cmd->phy_address != phydev->addr)
289                 return -EINVAL;
290
291         /* We make sure that we don't pass unsupported
292          * values in to the PHY */
293         cmd->advertising &= phydev->supported;
294
295         /* Verify the settings we care about. */
296         if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
297                 return -EINVAL;
298
299         if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
300                 return -EINVAL;
301
302         if (cmd->autoneg == AUTONEG_DISABLE
303                         && ((cmd->speed != SPEED_1000
304                                         && cmd->speed != SPEED_100
305                                         && cmd->speed != SPEED_10)
306                                 || (cmd->duplex != DUPLEX_HALF
307                                         && cmd->duplex != DUPLEX_FULL)))
308                 return -EINVAL;
309
310         phydev->autoneg = cmd->autoneg;
311
312         phydev->speed = cmd->speed;
313
314         phydev->advertising = cmd->advertising;
315
316         if (AUTONEG_ENABLE == cmd->autoneg)
317                 phydev->advertising |= ADVERTISED_Autoneg;
318         else
319                 phydev->advertising &= ~ADVERTISED_Autoneg;
320
321         phydev->duplex = cmd->duplex;
322
323         /* Restart the PHY */
324         phy_start_aneg(phydev);
325
326         return 0;
327 }
328 EXPORT_SYMBOL(phy_ethtool_sset);
329
330 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
331 {
332         cmd->supported = phydev->supported;
333
334         cmd->advertising = phydev->advertising;
335
336         cmd->speed = phydev->speed;
337         cmd->duplex = phydev->duplex;
338         cmd->port = PORT_MII;
339         cmd->phy_address = phydev->addr;
340         cmd->transceiver = XCVR_EXTERNAL;
341         cmd->autoneg = phydev->autoneg;
342
343         return 0;
344 }
345 EXPORT_SYMBOL(phy_ethtool_gset);
346
347 /**
348  * phy_mii_ioctl - generic PHY MII ioctl interface
349  * @phydev: the phy_device struct
350  * @mii_data: MII ioctl data
351  * @cmd: ioctl cmd to execute
352  *
353  * Note that this function is currently incompatible with the
354  * PHYCONTROL layer.  It changes registers without regard to
355  * current state.  Use at own risk.
356  */
357 int phy_mii_ioctl(struct phy_device *phydev,
358                 struct mii_ioctl_data *mii_data, int cmd)
359 {
360         u16 val = mii_data->val_in;
361
362         switch (cmd) {
363         case SIOCGMIIPHY:
364                 mii_data->phy_id = phydev->addr;
365                 break;
366         case SIOCGMIIREG:
367                 mii_data->val_out = phy_read(phydev, mii_data->reg_num);
368                 break;
369
370         case SIOCSMIIREG:
371                 if (!capable(CAP_NET_ADMIN))
372                         return -EPERM;
373
374                 if (mii_data->phy_id == phydev->addr) {
375                         switch(mii_data->reg_num) {
376                         case MII_BMCR:
377                                 if ((val & (BMCR_RESET|BMCR_ANENABLE)) == 0)
378                                         phydev->autoneg = AUTONEG_DISABLE;
379                                 else
380                                         phydev->autoneg = AUTONEG_ENABLE;
381                                 if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
382                                         phydev->duplex = DUPLEX_FULL;
383                                 else
384                                         phydev->duplex = DUPLEX_HALF;
385                                 if ((!phydev->autoneg) &&
386                                                 (val & BMCR_SPEED1000))
387                                         phydev->speed = SPEED_1000;
388                                 else if ((!phydev->autoneg) &&
389                                                 (val & BMCR_SPEED100))
390                                         phydev->speed = SPEED_100;
391                                 break;
392                         case MII_ADVERTISE:
393                                 phydev->advertising = val;
394                                 break;
395                         default:
396                                 /* do nothing */
397                                 break;
398                         }
399                 }
400
401                 phy_write(phydev, mii_data->reg_num, val);
402                 
403                 if (mii_data->reg_num == MII_BMCR 
404                                 && val & BMCR_RESET
405                                 && phydev->drv->config_init)
406                         phydev->drv->config_init(phydev);
407                 break;
408         }
409
410         return 0;
411 }
412
413 /**
414  * phy_start_aneg - start auto-negotiation for this PHY device
415  * @phydev: the phy_device struct
416  *
417  * Description: Sanitizes the settings (if we're not autonegotiating
418  *   them), and then calls the driver's config_aneg function.
419  *   If the PHYCONTROL Layer is operating, we change the state to
420  *   reflect the beginning of Auto-negotiation or forcing.
421  */
422 int phy_start_aneg(struct phy_device *phydev)
423 {
424         int err;
425
426         spin_lock(&phydev->lock);
427
428         if (AUTONEG_DISABLE == phydev->autoneg)
429                 phy_sanitize_settings(phydev);
430
431         err = phydev->drv->config_aneg(phydev);
432
433         if (err < 0)
434                 goto out_unlock;
435
436         if (phydev->state != PHY_HALTED) {
437                 if (AUTONEG_ENABLE == phydev->autoneg) {
438                         phydev->state = PHY_AN;
439                         phydev->link_timeout = PHY_AN_TIMEOUT;
440                 } else {
441                         phydev->state = PHY_FORCING;
442                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
443                 }
444         }
445
446 out_unlock:
447         spin_unlock(&phydev->lock);
448         return err;
449 }
450 EXPORT_SYMBOL(phy_start_aneg);
451
452
453 static void phy_change(struct work_struct *work);
454 static void phy_timer(unsigned long data);
455
456 /**
457  * phy_start_machine - start PHY state machine tracking
458  * @phydev: the phy_device struct
459  * @handler: callback function for state change notifications
460  *
461  * Description: The PHY infrastructure can run a state machine
462  *   which tracks whether the PHY is starting up, negotiating,
463  *   etc.  This function starts the timer which tracks the state
464  *   of the PHY.  If you want to be notified when the state changes,
465  *   pass in the callback @handler, otherwise, pass NULL.  If you
466  *   want to maintain your own state machine, do not call this
467  *   function.
468  */
469 void phy_start_machine(struct phy_device *phydev,
470                 void (*handler)(struct net_device *))
471 {
472         phydev->adjust_state = handler;
473
474         init_timer(&phydev->phy_timer);
475         phydev->phy_timer.function = &phy_timer;
476         phydev->phy_timer.data = (unsigned long) phydev;
477         mod_timer(&phydev->phy_timer, jiffies + HZ);
478 }
479
480 /**
481  * phy_stop_machine - stop the PHY state machine tracking
482  * @phydev: target phy_device struct
483  *
484  * Description: Stops the state machine timer, sets the state to UP
485  *   (unless it wasn't up yet). This function must be called BEFORE
486  *   phy_detach.
487  */
488 void phy_stop_machine(struct phy_device *phydev)
489 {
490         del_timer_sync(&phydev->phy_timer);
491
492         spin_lock(&phydev->lock);
493         if (phydev->state > PHY_UP)
494                 phydev->state = PHY_UP;
495         spin_unlock(&phydev->lock);
496
497         phydev->adjust_state = NULL;
498 }
499
500 /**
501  * phy_force_reduction - reduce PHY speed/duplex settings by one step
502  * @phydev: target phy_device struct
503  *
504  * Description: Reduces the speed/duplex settings by one notch,
505  *   in this order--
506  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
507  *   The function bottoms out at 10/HALF.
508  */
509 static void phy_force_reduction(struct phy_device *phydev)
510 {
511         int idx;
512
513         idx = phy_find_setting(phydev->speed, phydev->duplex);
514         
515         idx++;
516
517         idx = phy_find_valid(idx, phydev->supported);
518
519         phydev->speed = settings[idx].speed;
520         phydev->duplex = settings[idx].duplex;
521
522         pr_info("Trying %d/%s\n", phydev->speed,
523                         DUPLEX_FULL == phydev->duplex ?
524                         "FULL" : "HALF");
525 }
526
527
528 /**
529  * phy_error - enter HALTED state for this PHY device
530  * @phydev: target phy_device struct
531  *
532  * Moves the PHY to the HALTED state in response to a read
533  * or write error, and tells the controller the link is down.
534  * Must not be called from interrupt context, or while the
535  * phydev->lock is held.
536  */
537 void phy_error(struct phy_device *phydev)
538 {
539         spin_lock(&phydev->lock);
540         phydev->state = PHY_HALTED;
541         spin_unlock(&phydev->lock);
542 }
543
544 /**
545  * phy_interrupt - PHY interrupt handler
546  * @irq: interrupt line
547  * @phy_dat: phy_device pointer
548  *
549  * Description: When a PHY interrupt occurs, the handler disables
550  * interrupts, and schedules a work task to clear the interrupt.
551  */
552 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
553 {
554         struct phy_device *phydev = phy_dat;
555
556         if (PHY_HALTED == phydev->state)
557                 return IRQ_NONE;                /* It can't be ours.  */
558
559         /* The MDIO bus is not allowed to be written in interrupt
560          * context, so we need to disable the irq here.  A work
561          * queue will write the PHY to disable and clear the
562          * interrupt, and then reenable the irq line. */
563         disable_irq_nosync(irq);
564
565         schedule_work(&phydev->phy_queue);
566
567         return IRQ_HANDLED;
568 }
569
570 /**
571  * phy_enable_interrupts - Enable the interrupts from the PHY side
572  * @phydev: target phy_device struct
573  */
574 int phy_enable_interrupts(struct phy_device *phydev)
575 {
576         int err;
577
578         err = phy_clear_interrupt(phydev);
579
580         if (err < 0)
581                 return err;
582
583         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
584
585         return err;
586 }
587 EXPORT_SYMBOL(phy_enable_interrupts);
588
589 /**
590  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
591  * @phydev: target phy_device struct
592  */
593 int phy_disable_interrupts(struct phy_device *phydev)
594 {
595         int err;
596
597         /* Disable PHY interrupts */
598         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
599
600         if (err)
601                 goto phy_err;
602
603         /* Clear the interrupt */
604         err = phy_clear_interrupt(phydev);
605
606         if (err)
607                 goto phy_err;
608
609         return 0;
610
611 phy_err:
612         phy_error(phydev);
613
614         return err;
615 }
616 EXPORT_SYMBOL(phy_disable_interrupts);
617
618 /**
619  * phy_start_interrupts - request and enable interrupts for a PHY device
620  * @phydev: target phy_device struct
621  *
622  * Description: Request the interrupt for the given PHY.
623  *   If this fails, then we set irq to PHY_POLL.
624  *   Otherwise, we enable the interrupts in the PHY.
625  *   This should only be called with a valid IRQ number.
626  *   Returns 0 on success or < 0 on error.
627  */
628 int phy_start_interrupts(struct phy_device *phydev)
629 {
630         int err = 0;
631
632         INIT_WORK(&phydev->phy_queue, phy_change);
633
634         if (request_irq(phydev->irq, phy_interrupt,
635                                 IRQF_SHARED,
636                                 "phy_interrupt",
637                                 phydev) < 0) {
638                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
639                                 phydev->bus->name,
640                                 phydev->irq);
641                 phydev->irq = PHY_POLL;
642                 return 0;
643         }
644
645         err = phy_enable_interrupts(phydev);
646
647         return err;
648 }
649 EXPORT_SYMBOL(phy_start_interrupts);
650
651 /**
652  * phy_stop_interrupts - disable interrupts from a PHY device
653  * @phydev: target phy_device struct
654  */
655 int phy_stop_interrupts(struct phy_device *phydev)
656 {
657         int err;
658
659         err = phy_disable_interrupts(phydev);
660
661         if (err)
662                 phy_error(phydev);
663
664         /*
665          * Finish any pending work; we might have been scheduled to be called
666          * from keventd ourselves, but cancel_work_sync() handles that.
667          */
668         cancel_work_sync(&phydev->phy_queue);
669
670         free_irq(phydev->irq, phydev);
671
672         return err;
673 }
674 EXPORT_SYMBOL(phy_stop_interrupts);
675
676
677 /**
678  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
679  * @work: work_struct that describes the work to be done
680  */
681 static void phy_change(struct work_struct *work)
682 {
683         int err;
684         struct phy_device *phydev =
685                 container_of(work, struct phy_device, phy_queue);
686
687         err = phy_disable_interrupts(phydev);
688
689         if (err)
690                 goto phy_err;
691
692         spin_lock(&phydev->lock);
693         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
694                 phydev->state = PHY_CHANGELINK;
695         spin_unlock(&phydev->lock);
696
697         enable_irq(phydev->irq);
698
699         /* Reenable interrupts */
700         if (PHY_HALTED != phydev->state)
701                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
702
703         if (err)
704                 goto irq_enable_err;
705
706         return;
707
708 irq_enable_err:
709         disable_irq(phydev->irq);
710 phy_err:
711         phy_error(phydev);
712 }
713
714 /**
715  * phy_stop - Bring down the PHY link, and stop checking the status
716  * @phydev: target phy_device struct
717  */
718 void phy_stop(struct phy_device *phydev)
719 {
720         spin_lock(&phydev->lock);
721
722         if (PHY_HALTED == phydev->state)
723                 goto out_unlock;
724
725         phydev->state = PHY_HALTED;
726
727         if (phydev->irq != PHY_POLL) {
728                 /* Disable PHY Interrupts */
729                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
730
731                 /* Clear any pending interrupts */
732                 phy_clear_interrupt(phydev);
733         }
734
735 out_unlock:
736         spin_unlock(&phydev->lock);
737
738         /*
739          * Cannot call flush_scheduled_work() here as desired because
740          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
741          * will not reenable interrupts.
742          */
743 }
744
745
746 /**
747  * phy_start - start or restart a PHY device
748  * @phydev: target phy_device struct
749  *
750  * Description: Indicates the attached device's readiness to
751  *   handle PHY-related work.  Used during startup to start the
752  *   PHY, and after a call to phy_stop() to resume operation.
753  *   Also used to indicate the MDIO bus has cleared an error
754  *   condition.
755  */
756 void phy_start(struct phy_device *phydev)
757 {
758         spin_lock(&phydev->lock);
759
760         switch (phydev->state) {
761                 case PHY_STARTING:
762                         phydev->state = PHY_PENDING;
763                         break;
764                 case PHY_READY:
765                         phydev->state = PHY_UP;
766                         break;
767                 case PHY_HALTED:
768                         phydev->state = PHY_RESUMING;
769                 default:
770                         break;
771         }
772         spin_unlock(&phydev->lock);
773 }
774 EXPORT_SYMBOL(phy_stop);
775 EXPORT_SYMBOL(phy_start);
776
777 /* PHY timer which handles the state machine */
778 static void phy_timer(unsigned long data)
779 {
780         struct phy_device *phydev = (struct phy_device *)data;
781         int needs_aneg = 0;
782         int err = 0;
783
784         spin_lock(&phydev->lock);
785
786         if (phydev->adjust_state)
787                 phydev->adjust_state(phydev->attached_dev);
788
789         switch(phydev->state) {
790                 case PHY_DOWN:
791                 case PHY_STARTING:
792                 case PHY_READY:
793                 case PHY_PENDING:
794                         break;
795                 case PHY_UP:
796                         needs_aneg = 1;
797
798                         phydev->link_timeout = PHY_AN_TIMEOUT;
799
800                         break;
801                 case PHY_AN:
802                         err = phy_read_status(phydev);
803
804                         if (err < 0)
805                                 break;
806
807                         /* If the link is down, give up on
808                          * negotiation for now */
809                         if (!phydev->link) {
810                                 phydev->state = PHY_NOLINK;
811                                 netif_carrier_off(phydev->attached_dev);
812                                 phydev->adjust_link(phydev->attached_dev);
813                                 break;
814                         }
815
816                         /* Check if negotiation is done.  Break
817                          * if there's an error */
818                         err = phy_aneg_done(phydev);
819                         if (err < 0)
820                                 break;
821
822                         /* If AN is done, we're running */
823                         if (err > 0) {
824                                 phydev->state = PHY_RUNNING;
825                                 netif_carrier_on(phydev->attached_dev);
826                                 phydev->adjust_link(phydev->attached_dev);
827
828                         } else if (0 == phydev->link_timeout--) {
829                                 int idx;
830
831                                 needs_aneg = 1;
832                                 /* If we have the magic_aneg bit,
833                                  * we try again */
834                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
835                                         break;
836
837                                 /* The timer expired, and we still
838                                  * don't have a setting, so we try
839                                  * forcing it until we find one that
840                                  * works, starting from the fastest speed,
841                                  * and working our way down */
842                                 idx = phy_find_valid(0, phydev->supported);
843
844                                 phydev->speed = settings[idx].speed;
845                                 phydev->duplex = settings[idx].duplex;
846
847                                 phydev->autoneg = AUTONEG_DISABLE;
848
849                                 pr_info("Trying %d/%s\n", phydev->speed,
850                                                 DUPLEX_FULL ==
851                                                 phydev->duplex ?
852                                                 "FULL" : "HALF");
853                         }
854                         break;
855                 case PHY_NOLINK:
856                         err = phy_read_status(phydev);
857
858                         if (err)
859                                 break;
860
861                         if (phydev->link) {
862                                 phydev->state = PHY_RUNNING;
863                                 netif_carrier_on(phydev->attached_dev);
864                                 phydev->adjust_link(phydev->attached_dev);
865                         }
866                         break;
867                 case PHY_FORCING:
868                         err = genphy_update_link(phydev);
869
870                         if (err)
871                                 break;
872
873                         if (phydev->link) {
874                                 phydev->state = PHY_RUNNING;
875                                 netif_carrier_on(phydev->attached_dev);
876                         } else {
877                                 if (0 == phydev->link_timeout--) {
878                                         phy_force_reduction(phydev);
879                                         needs_aneg = 1;
880                                 }
881                         }
882
883                         phydev->adjust_link(phydev->attached_dev);
884                         break;
885                 case PHY_RUNNING:
886                         /* Only register a CHANGE if we are
887                          * polling */
888                         if (PHY_POLL == phydev->irq)
889                                 phydev->state = PHY_CHANGELINK;
890                         break;
891                 case PHY_CHANGELINK:
892                         err = phy_read_status(phydev);
893
894                         if (err)
895                                 break;
896
897                         if (phydev->link) {
898                                 phydev->state = PHY_RUNNING;
899                                 netif_carrier_on(phydev->attached_dev);
900                         } else {
901                                 phydev->state = PHY_NOLINK;
902                                 netif_carrier_off(phydev->attached_dev);
903                         }
904
905                         phydev->adjust_link(phydev->attached_dev);
906
907                         if (PHY_POLL != phydev->irq)
908                                 err = phy_config_interrupt(phydev,
909                                                 PHY_INTERRUPT_ENABLED);
910                         break;
911                 case PHY_HALTED:
912                         if (phydev->link) {
913                                 phydev->link = 0;
914                                 netif_carrier_off(phydev->attached_dev);
915                                 phydev->adjust_link(phydev->attached_dev);
916                         }
917                         break;
918                 case PHY_RESUMING:
919
920                         err = phy_clear_interrupt(phydev);
921
922                         if (err)
923                                 break;
924
925                         err = phy_config_interrupt(phydev,
926                                         PHY_INTERRUPT_ENABLED);
927
928                         if (err)
929                                 break;
930
931                         if (AUTONEG_ENABLE == phydev->autoneg) {
932                                 err = phy_aneg_done(phydev);
933                                 if (err < 0)
934                                         break;
935
936                                 /* err > 0 if AN is done.
937                                  * Otherwise, it's 0, and we're
938                                  * still waiting for AN */
939                                 if (err > 0) {
940                                         phydev->state = PHY_RUNNING;
941                                 } else {
942                                         phydev->state = PHY_AN;
943                                         phydev->link_timeout = PHY_AN_TIMEOUT;
944                                 }
945                         } else
946                                 phydev->state = PHY_RUNNING;
947                         break;
948         }
949
950         spin_unlock(&phydev->lock);
951
952         if (needs_aneg)
953                 err = phy_start_aneg(phydev);
954
955         if (err < 0)
956                 phy_error(phydev);
957
958         mod_timer(&phydev->phy_timer, jiffies + PHY_STATE_TIME * HZ);
959 }
960