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, 2007 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/interrupt.h>
23 #include <linux/init.h>
24 #include <linux/delay.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/skbuff.h>
28 #include <linux/mm.h>
29 #include <linux/module.h>
30 #include <linux/mii.h>
31 #include <linux/ethtool.h>
32 #include <linux/phy.h>
33 #include <linux/timer.h>
34 #include <linux/workqueue.h>
35
36 #include <asm/atomic.h>
37 #include <asm/io.h>
38 #include <asm/irq.h>
39 #include <asm/uaccess.h>
40
41 /**
42 * phy_print_status - Convenience function to print out the current phy status
43 * @phydev: the phy_device struct
44 */
phy_print_status(struct phy_device * phydev)45 void phy_print_status(struct phy_device *phydev)
46 {
47 pr_info("PHY: %s - Link is %s", dev_name(&phydev->dev),
48 phydev->link ? "Up" : "Down");
49 if (phydev->link)
50 printk(KERN_CONT " - %d/%s", phydev->speed,
51 DUPLEX_FULL == phydev->duplex ?
52 "Full" : "Half");
53
54 printk(KERN_CONT "\n");
55 }
56 EXPORT_SYMBOL(phy_print_status);
57
58
59 /**
60 * phy_clear_interrupt - Ack the phy device's interrupt
61 * @phydev: the phy_device struct
62 *
63 * If the @phydev driver has an ack_interrupt function, call it to
64 * ack and clear the phy device's interrupt.
65 *
66 * Returns 0 on success on < 0 on error.
67 */
phy_clear_interrupt(struct phy_device * phydev)68 static int phy_clear_interrupt(struct phy_device *phydev)
69 {
70 int err = 0;
71
72 if (phydev->drv->ack_interrupt)
73 err = phydev->drv->ack_interrupt(phydev);
74
75 return err;
76 }
77
78 /**
79 * phy_config_interrupt - configure the PHY device for the requested interrupts
80 * @phydev: the phy_device struct
81 * @interrupts: interrupt flags to configure for this @phydev
82 *
83 * Returns 0 on success on < 0 on error.
84 */
phy_config_interrupt(struct phy_device * phydev,u32 interrupts)85 static int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
86 {
87 int err = 0;
88
89 phydev->interrupts = interrupts;
90 if (phydev->drv->config_intr)
91 err = phydev->drv->config_intr(phydev);
92
93 return err;
94 }
95
96
97 /**
98 * phy_aneg_done - return auto-negotiation status
99 * @phydev: target phy_device struct
100 *
101 * Description: Reads the status register and returns 0 either if
102 * auto-negotiation is incomplete, or if there was an error.
103 * Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
104 */
phy_aneg_done(struct phy_device * phydev)105 static inline int phy_aneg_done(struct phy_device *phydev)
106 {
107 int retval;
108
109 retval = phy_read(phydev, MII_BMSR);
110
111 return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
112 }
113
114 /* A structure for mapping a particular speed and duplex
115 * combination to a particular SUPPORTED and ADVERTISED value */
116 struct phy_setting {
117 int speed;
118 int duplex;
119 u32 setting;
120 };
121
122 /* A mapping of all SUPPORTED settings to speed/duplex */
123 static const struct phy_setting settings[] = {
124 {
125 .speed = 10000,
126 .duplex = DUPLEX_FULL,
127 .setting = SUPPORTED_10000baseT_Full,
128 },
129 {
130 .speed = SPEED_1000,
131 .duplex = DUPLEX_FULL,
132 .setting = SUPPORTED_1000baseT_Full,
133 },
134 {
135 .speed = SPEED_1000,
136 .duplex = DUPLEX_HALF,
137 .setting = SUPPORTED_1000baseT_Half,
138 },
139 {
140 .speed = SPEED_100,
141 .duplex = DUPLEX_FULL,
142 .setting = SUPPORTED_100baseT_Full,
143 },
144 {
145 .speed = SPEED_100,
146 .duplex = DUPLEX_HALF,
147 .setting = SUPPORTED_100baseT_Half,
148 },
149 {
150 .speed = SPEED_10,
151 .duplex = DUPLEX_FULL,
152 .setting = SUPPORTED_10baseT_Full,
153 },
154 {
155 .speed = SPEED_10,
156 .duplex = DUPLEX_HALF,
157 .setting = SUPPORTED_10baseT_Half,
158 },
159 };
160
161 #define MAX_NUM_SETTINGS ARRAY_SIZE(settings)
162
163 /**
164 * phy_find_setting - find a PHY settings array entry that matches speed & duplex
165 * @speed: speed to match
166 * @duplex: duplex to match
167 *
168 * Description: Searches the settings array for the setting which
169 * matches the desired speed and duplex, and returns the index
170 * of that setting. Returns the index of the last setting if
171 * none of the others match.
172 */
phy_find_setting(int speed,int duplex)173 static inline int phy_find_setting(int speed, int duplex)
174 {
175 int idx = 0;
176
177 while (idx < ARRAY_SIZE(settings) &&
178 (settings[idx].speed != speed ||
179 settings[idx].duplex != duplex))
180 idx++;
181
182 return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
183 }
184
185 /**
186 * phy_find_valid - find a PHY setting that matches the requested features mask
187 * @idx: The first index in settings[] to search
188 * @features: A mask of the valid settings
189 *
190 * Description: Returns the index of the first valid setting less
191 * than or equal to the one pointed to by idx, as determined by
192 * the mask in features. Returns the index of the last setting
193 * if nothing else matches.
194 */
phy_find_valid(int idx,u32 features)195 static inline int phy_find_valid(int idx, u32 features)
196 {
197 while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
198 idx++;
199
200 return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
201 }
202
203 /**
204 * phy_sanitize_settings - make sure the PHY is set to supported speed and duplex
205 * @phydev: the target phy_device struct
206 *
207 * Description: Make sure the PHY is set to supported speeds and
208 * duplexes. Drop down by one in this order: 1000/FULL,
209 * 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
210 */
phy_sanitize_settings(struct phy_device * phydev)211 static void phy_sanitize_settings(struct phy_device *phydev)
212 {
213 u32 features = phydev->supported;
214 int idx;
215
216 /* Sanitize settings based on PHY capabilities */
217 if ((features & SUPPORTED_Autoneg) == 0)
218 phydev->autoneg = AUTONEG_DISABLE;
219
220 idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
221 features);
222
223 phydev->speed = settings[idx].speed;
224 phydev->duplex = settings[idx].duplex;
225 }
226
227 /**
228 * phy_ethtool_sset - generic ethtool sset function, handles all the details
229 * @phydev: target phy_device struct
230 * @cmd: ethtool_cmd
231 *
232 * A few notes about parameter checking:
233 * - We don't set port or transceiver, so we don't care what they
234 * were set to.
235 * - phy_start_aneg() will make sure forced settings are sane, and
236 * choose the next best ones from the ones selected, so we don't
237 * care if ethtool tries to give us bad values.
238 */
phy_ethtool_sset(struct phy_device * phydev,struct ethtool_cmd * cmd)239 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
240 {
241 if (cmd->phy_address != phydev->addr)
242 return -EINVAL;
243
244 /* We make sure that we don't pass unsupported
245 * values in to the PHY */
246 cmd->advertising &= phydev->supported;
247
248 /* Verify the settings we care about. */
249 if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
250 return -EINVAL;
251
252 if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
253 return -EINVAL;
254
255 if (cmd->autoneg == AUTONEG_DISABLE &&
256 ((cmd->speed != SPEED_1000 &&
257 cmd->speed != SPEED_100 &&
258 cmd->speed != SPEED_10) ||
259 (cmd->duplex != DUPLEX_HALF &&
260 cmd->duplex != DUPLEX_FULL)))
261 return -EINVAL;
262
263 phydev->autoneg = cmd->autoneg;
264
265 phydev->speed = cmd->speed;
266
267 phydev->advertising = cmd->advertising;
268
269 if (AUTONEG_ENABLE == cmd->autoneg)
270 phydev->advertising |= ADVERTISED_Autoneg;
271 else
272 phydev->advertising &= ~ADVERTISED_Autoneg;
273
274 phydev->duplex = cmd->duplex;
275
276 /* Restart the PHY */
277 phy_start_aneg(phydev);
278
279 return 0;
280 }
281 EXPORT_SYMBOL(phy_ethtool_sset);
282
phy_ethtool_gset(struct phy_device * phydev,struct ethtool_cmd * cmd)283 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
284 {
285 cmd->supported = phydev->supported;
286
287 cmd->advertising = phydev->advertising;
288
289 cmd->speed = phydev->speed;
290 cmd->duplex = phydev->duplex;
291 cmd->port = PORT_MII;
292 cmd->phy_address = phydev->addr;
293 cmd->transceiver = XCVR_EXTERNAL;
294 cmd->autoneg = phydev->autoneg;
295
296 return 0;
297 }
298 EXPORT_SYMBOL(phy_ethtool_gset);
299
300 /**
301 * phy_mii_ioctl - generic PHY MII ioctl interface
302 * @phydev: the phy_device struct
303 * @ifr: &struct ifreq for socket ioctl's
304 * @cmd: ioctl cmd to execute
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 */
phy_mii_ioctl(struct phy_device * phydev,struct ifreq * ifr,int cmd)310 int phy_mii_ioctl(struct phy_device *phydev,
311 struct ifreq *ifr, int cmd)
312 {
313 struct mii_ioctl_data *mii_data = if_mii(ifr);
314 u16 val = mii_data->val_in;
315
316 switch (cmd) {
317 case SIOCGMIIPHY:
318 mii_data->phy_id = phydev->addr;
319 /* fall through */
320
321 case SIOCGMIIREG:
322 mii_data->val_out = mdiobus_read(phydev->bus, mii_data->phy_id,
323 mii_data->reg_num);
324 break;
325
326 case SIOCSMIIREG:
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)) == 0)
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 if ((!phydev->autoneg) &&
339 (val & BMCR_SPEED1000))
340 phydev->speed = SPEED_1000;
341 else if ((!phydev->autoneg) &&
342 (val & BMCR_SPEED100))
343 phydev->speed = SPEED_100;
344 break;
345 case MII_ADVERTISE:
346 phydev->advertising = val;
347 break;
348 default:
349 /* do nothing */
350 break;
351 }
352 }
353
354 mdiobus_write(phydev->bus, mii_data->phy_id,
355 mii_data->reg_num, val);
356
357 if (mii_data->reg_num == MII_BMCR &&
358 val & BMCR_RESET &&
359 phydev->drv->config_init) {
360 phy_scan_fixups(phydev);
361 phydev->drv->config_init(phydev);
362 }
363 break;
364
365 case SIOCSHWTSTAMP:
366 if (phydev->drv->hwtstamp)
367 return phydev->drv->hwtstamp(phydev, ifr);
368 /* fall through */
369
370 default:
371 return -EOPNOTSUPP;
372 }
373
374 return 0;
375 }
376 EXPORT_SYMBOL(phy_mii_ioctl);
377
378 /**
379 * phy_start_aneg - start auto-negotiation for this PHY device
380 * @phydev: the phy_device struct
381 *
382 * Description: Sanitizes the settings (if we're not autonegotiating
383 * them), and then calls the driver's config_aneg function.
384 * If the PHYCONTROL Layer is operating, we change the state to
385 * reflect the beginning of Auto-negotiation or forcing.
386 */
phy_start_aneg(struct phy_device * phydev)387 int phy_start_aneg(struct phy_device *phydev)
388 {
389 int err;
390
391 mutex_lock(&phydev->lock);
392
393 if (AUTONEG_DISABLE == phydev->autoneg)
394 phy_sanitize_settings(phydev);
395
396 err = phydev->drv->config_aneg(phydev);
397
398 if (err < 0)
399 goto out_unlock;
400
401 if (phydev->state != PHY_HALTED) {
402 if (AUTONEG_ENABLE == phydev->autoneg) {
403 phydev->state = PHY_AN;
404 phydev->link_timeout = PHY_AN_TIMEOUT;
405 } else {
406 phydev->state = PHY_FORCING;
407 phydev->link_timeout = PHY_FORCE_TIMEOUT;
408 }
409 }
410
411 out_unlock:
412 mutex_unlock(&phydev->lock);
413 return err;
414 }
415 EXPORT_SYMBOL(phy_start_aneg);
416
417
418 static void phy_change(struct work_struct *work);
419
420 /**
421 * phy_start_machine - start PHY state machine tracking
422 * @phydev: the phy_device struct
423 * @handler: callback function for state change notifications
424 *
425 * Description: The PHY infrastructure can run a state machine
426 * which tracks whether the PHY is starting up, negotiating,
427 * etc. This function starts the timer which tracks the state
428 * of the PHY. If you want to be notified when the state changes,
429 * pass in the callback @handler, otherwise, pass NULL. If you
430 * want to maintain your own state machine, do not call this
431 * function.
432 */
phy_start_machine(struct phy_device * phydev,void (* handler)(struct net_device *))433 void phy_start_machine(struct phy_device *phydev,
434 void (*handler)(struct net_device *))
435 {
436 phydev->adjust_state = handler;
437
438 schedule_delayed_work(&phydev->state_queue, HZ);
439 }
440
441 /**
442 * phy_stop_machine - stop the PHY state machine tracking
443 * @phydev: target phy_device struct
444 *
445 * Description: Stops the state machine timer, sets the state to UP
446 * (unless it wasn't up yet). This function must be called BEFORE
447 * phy_detach.
448 */
phy_stop_machine(struct phy_device * phydev)449 void phy_stop_machine(struct phy_device *phydev)
450 {
451 cancel_delayed_work_sync(&phydev->state_queue);
452
453 mutex_lock(&phydev->lock);
454 if (phydev->state > PHY_UP)
455 phydev->state = PHY_UP;
456 mutex_unlock(&phydev->lock);
457
458 phydev->adjust_state = NULL;
459 }
460
461 /**
462 * phy_force_reduction - reduce PHY speed/duplex settings by one step
463 * @phydev: target phy_device struct
464 *
465 * Description: Reduces the speed/duplex settings by one notch,
466 * in this order--
467 * 1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
468 * The function bottoms out at 10/HALF.
469 */
phy_force_reduction(struct phy_device * phydev)470 static void phy_force_reduction(struct phy_device *phydev)
471 {
472 int idx;
473
474 idx = phy_find_setting(phydev->speed, phydev->duplex);
475
476 idx++;
477
478 idx = phy_find_valid(idx, phydev->supported);
479
480 phydev->speed = settings[idx].speed;
481 phydev->duplex = settings[idx].duplex;
482
483 pr_info("Trying %d/%s\n", phydev->speed,
484 DUPLEX_FULL == phydev->duplex ?
485 "FULL" : "HALF");
486 }
487
488
489 /**
490 * phy_error - enter HALTED state for this PHY device
491 * @phydev: target phy_device struct
492 *
493 * Moves the PHY to the HALTED state in response to a read
494 * or write error, and tells the controller the link is down.
495 * Must not be called from interrupt context, or while the
496 * phydev->lock is held.
497 */
phy_error(struct phy_device * phydev)498 static void phy_error(struct phy_device *phydev)
499 {
500 mutex_lock(&phydev->lock);
501 phydev->state = PHY_HALTED;
502 mutex_unlock(&phydev->lock);
503 }
504
505 /**
506 * phy_interrupt - PHY interrupt handler
507 * @irq: interrupt line
508 * @phy_dat: phy_device pointer
509 *
510 * Description: When a PHY interrupt occurs, the handler disables
511 * interrupts, and schedules a work task to clear the interrupt.
512 */
phy_interrupt(int irq,void * phy_dat)513 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
514 {
515 struct phy_device *phydev = phy_dat;
516
517 if (PHY_HALTED == phydev->state)
518 return IRQ_NONE; /* It can't be ours. */
519
520 /* The MDIO bus is not allowed to be written in interrupt
521 * context, so we need to disable the irq here. A work
522 * queue will write the PHY to disable and clear the
523 * interrupt, and then reenable the irq line. */
524 disable_irq_nosync(irq);
525 atomic_inc(&phydev->irq_disable);
526
527 schedule_work(&phydev->phy_queue);
528
529 return IRQ_HANDLED;
530 }
531
532 /**
533 * phy_enable_interrupts - Enable the interrupts from the PHY side
534 * @phydev: target phy_device struct
535 */
phy_enable_interrupts(struct phy_device * phydev)536 static int phy_enable_interrupts(struct phy_device *phydev)
537 {
538 int err;
539
540 err = phy_clear_interrupt(phydev);
541
542 if (err < 0)
543 return err;
544
545 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
546
547 return err;
548 }
549
550 /**
551 * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
552 * @phydev: target phy_device struct
553 */
phy_disable_interrupts(struct phy_device * phydev)554 static int phy_disable_interrupts(struct phy_device *phydev)
555 {
556 int err;
557
558 /* Disable PHY interrupts */
559 err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
560
561 if (err)
562 goto phy_err;
563
564 /* Clear the interrupt */
565 err = phy_clear_interrupt(phydev);
566
567 if (err)
568 goto phy_err;
569
570 return 0;
571
572 phy_err:
573 phy_error(phydev);
574
575 return err;
576 }
577
578 /**
579 * phy_start_interrupts - request and enable interrupts for a PHY device
580 * @phydev: target phy_device struct
581 *
582 * Description: Request the interrupt for the given PHY.
583 * If this fails, then we set irq to PHY_POLL.
584 * Otherwise, we enable the interrupts in the PHY.
585 * This should only be called with a valid IRQ number.
586 * Returns 0 on success or < 0 on error.
587 */
phy_start_interrupts(struct phy_device * phydev)588 int phy_start_interrupts(struct phy_device *phydev)
589 {
590 int err = 0;
591
592 INIT_WORK(&phydev->phy_queue, phy_change);
593
594 atomic_set(&phydev->irq_disable, 0);
595 if (request_irq(phydev->irq, phy_interrupt,
596 IRQF_SHARED,
597 "phy_interrupt",
598 phydev) < 0) {
599 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
600 phydev->bus->name,
601 phydev->irq);
602 phydev->irq = PHY_POLL;
603 return 0;
604 }
605
606 err = phy_enable_interrupts(phydev);
607
608 return err;
609 }
610 EXPORT_SYMBOL(phy_start_interrupts);
611
612 /**
613 * phy_stop_interrupts - disable interrupts from a PHY device
614 * @phydev: target phy_device struct
615 */
phy_stop_interrupts(struct phy_device * phydev)616 int phy_stop_interrupts(struct phy_device *phydev)
617 {
618 int err;
619
620 err = phy_disable_interrupts(phydev);
621
622 if (err)
623 phy_error(phydev);
624
625 free_irq(phydev->irq, phydev);
626
627 /*
628 * Cannot call flush_scheduled_work() here as desired because
629 * of rtnl_lock(), but we do not really care about what would
630 * be done, except from enable_irq(), so cancel any work
631 * possibly pending and take care of the matter below.
632 */
633 cancel_work_sync(&phydev->phy_queue);
634 /*
635 * If work indeed has been cancelled, disable_irq() will have
636 * been left unbalanced from phy_interrupt() and enable_irq()
637 * has to be called so that other devices on the line work.
638 */
639 while (atomic_dec_return(&phydev->irq_disable) >= 0)
640 enable_irq(phydev->irq);
641
642 return err;
643 }
644 EXPORT_SYMBOL(phy_stop_interrupts);
645
646
647 /**
648 * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
649 * @work: work_struct that describes the work to be done
650 */
phy_change(struct work_struct * work)651 static void phy_change(struct work_struct *work)
652 {
653 int err;
654 struct phy_device *phydev =
655 container_of(work, struct phy_device, phy_queue);
656
657 if (phydev->drv->did_interrupt &&
658 !phydev->drv->did_interrupt(phydev))
659 goto ignore;
660
661 err = phy_disable_interrupts(phydev);
662
663 if (err)
664 goto phy_err;
665
666 mutex_lock(&phydev->lock);
667 if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
668 phydev->state = PHY_CHANGELINK;
669 mutex_unlock(&phydev->lock);
670
671 atomic_dec(&phydev->irq_disable);
672 enable_irq(phydev->irq);
673
674 /* Reenable interrupts */
675 if (PHY_HALTED != phydev->state)
676 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
677
678 if (err)
679 goto irq_enable_err;
680
681 /* reschedule state queue work to run as soon as possible */
682 cancel_delayed_work_sync(&phydev->state_queue);
683 schedule_delayed_work(&phydev->state_queue, 0);
684
685 return;
686
687 ignore:
688 atomic_dec(&phydev->irq_disable);
689 enable_irq(phydev->irq);
690 return;
691
692 irq_enable_err:
693 disable_irq(phydev->irq);
694 atomic_inc(&phydev->irq_disable);
695 phy_err:
696 phy_error(phydev);
697 }
698
699 /**
700 * phy_stop - Bring down the PHY link, and stop checking the status
701 * @phydev: target phy_device struct
702 */
phy_stop(struct phy_device * phydev)703 void phy_stop(struct phy_device *phydev)
704 {
705 mutex_lock(&phydev->lock);
706
707 if (PHY_HALTED == phydev->state)
708 goto out_unlock;
709
710 if (phydev->irq != PHY_POLL) {
711 /* Disable PHY Interrupts */
712 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
713
714 /* Clear any pending interrupts */
715 phy_clear_interrupt(phydev);
716 }
717
718 phydev->state = PHY_HALTED;
719
720 out_unlock:
721 mutex_unlock(&phydev->lock);
722
723 /*
724 * Cannot call flush_scheduled_work() here as desired because
725 * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
726 * will not reenable interrupts.
727 */
728 }
729
730
731 /**
732 * phy_start - start or restart a PHY device
733 * @phydev: target phy_device struct
734 *
735 * Description: Indicates the attached device's readiness to
736 * handle PHY-related work. Used during startup to start the
737 * PHY, and after a call to phy_stop() to resume operation.
738 * Also used to indicate the MDIO bus has cleared an error
739 * condition.
740 */
phy_start(struct phy_device * phydev)741 void phy_start(struct phy_device *phydev)
742 {
743 mutex_lock(&phydev->lock);
744
745 switch (phydev->state) {
746 case PHY_STARTING:
747 phydev->state = PHY_PENDING;
748 break;
749 case PHY_READY:
750 phydev->state = PHY_UP;
751 break;
752 case PHY_HALTED:
753 phydev->state = PHY_RESUMING;
754 default:
755 break;
756 }
757 mutex_unlock(&phydev->lock);
758 }
759 EXPORT_SYMBOL(phy_stop);
760 EXPORT_SYMBOL(phy_start);
761
762 /**
763 * phy_state_machine - Handle the state machine
764 * @work: work_struct that describes the work to be done
765 */
phy_state_machine(struct work_struct * work)766 void phy_state_machine(struct work_struct *work)
767 {
768 struct delayed_work *dwork = to_delayed_work(work);
769 struct phy_device *phydev =
770 container_of(dwork, struct phy_device, state_queue);
771 int needs_aneg = 0;
772 int err = 0;
773
774 mutex_lock(&phydev->lock);
775
776 if (phydev->adjust_state)
777 phydev->adjust_state(phydev->attached_dev);
778
779 switch(phydev->state) {
780 case PHY_DOWN:
781 case PHY_STARTING:
782 case PHY_READY:
783 case PHY_PENDING:
784 break;
785 case PHY_UP:
786 needs_aneg = 1;
787
788 phydev->link_timeout = PHY_AN_TIMEOUT;
789
790 break;
791 case PHY_AN:
792 err = phy_read_status(phydev);
793
794 if (err < 0)
795 break;
796
797 /* If the link is down, give up on
798 * negotiation for now */
799 if (!phydev->link) {
800 phydev->state = PHY_NOLINK;
801 netif_carrier_off(phydev->attached_dev);
802 phydev->adjust_link(phydev->attached_dev);
803 break;
804 }
805
806 /* Check if negotiation is done. Break
807 * if there's an error */
808 err = phy_aneg_done(phydev);
809 if (err < 0)
810 break;
811
812 /* If AN is done, we're running */
813 if (err > 0) {
814 phydev->state = PHY_RUNNING;
815 netif_carrier_on(phydev->attached_dev);
816 phydev->adjust_link(phydev->attached_dev);
817
818 } else if (0 == phydev->link_timeout--) {
819 int idx;
820
821 needs_aneg = 1;
822 /* If we have the magic_aneg bit,
823 * we try again */
824 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
825 break;
826
827 /* The timer expired, and we still
828 * don't have a setting, so we try
829 * forcing it until we find one that
830 * works, starting from the fastest speed,
831 * and working our way down */
832 idx = phy_find_valid(0, phydev->supported);
833
834 phydev->speed = settings[idx].speed;
835 phydev->duplex = settings[idx].duplex;
836
837 phydev->autoneg = AUTONEG_DISABLE;
838
839 pr_info("Trying %d/%s\n", phydev->speed,
840 DUPLEX_FULL ==
841 phydev->duplex ?
842 "FULL" : "HALF");
843 }
844 break;
845 case PHY_NOLINK:
846 err = phy_read_status(phydev);
847
848 if (err)
849 break;
850
851 if (phydev->link) {
852 phydev->state = PHY_RUNNING;
853 netif_carrier_on(phydev->attached_dev);
854 phydev->adjust_link(phydev->attached_dev);
855 }
856 break;
857 case PHY_FORCING:
858 err = genphy_update_link(phydev);
859
860 if (err)
861 break;
862
863 if (phydev->link) {
864 phydev->state = PHY_RUNNING;
865 netif_carrier_on(phydev->attached_dev);
866 } else {
867 if (0 == phydev->link_timeout--) {
868 phy_force_reduction(phydev);
869 needs_aneg = 1;
870 }
871 }
872
873 phydev->adjust_link(phydev->attached_dev);
874 break;
875 case PHY_RUNNING:
876 /* Only register a CHANGE if we are
877 * polling */
878 if (PHY_POLL == phydev->irq)
879 phydev->state = PHY_CHANGELINK;
880 break;
881 case PHY_CHANGELINK:
882 err = phy_read_status(phydev);
883
884 if (err)
885 break;
886
887 if (phydev->link) {
888 phydev->state = PHY_RUNNING;
889 netif_carrier_on(phydev->attached_dev);
890 } else {
891 phydev->state = PHY_NOLINK;
892 netif_carrier_off(phydev->attached_dev);
893 }
894
895 phydev->adjust_link(phydev->attached_dev);
896
897 if (PHY_POLL != phydev->irq)
898 err = phy_config_interrupt(phydev,
899 PHY_INTERRUPT_ENABLED);
900 break;
901 case PHY_HALTED:
902 if (phydev->link) {
903 phydev->link = 0;
904 netif_carrier_off(phydev->attached_dev);
905 phydev->adjust_link(phydev->attached_dev);
906 }
907 break;
908 case PHY_RESUMING:
909
910 err = phy_clear_interrupt(phydev);
911
912 if (err)
913 break;
914
915 err = phy_config_interrupt(phydev,
916 PHY_INTERRUPT_ENABLED);
917
918 if (err)
919 break;
920
921 if (AUTONEG_ENABLE == phydev->autoneg) {
922 err = phy_aneg_done(phydev);
923 if (err < 0)
924 break;
925
926 /* err > 0 if AN is done.
927 * Otherwise, it's 0, and we're
928 * still waiting for AN */
929 if (err > 0) {
930 err = phy_read_status(phydev);
931 if (err)
932 break;
933
934 if (phydev->link) {
935 phydev->state = PHY_RUNNING;
936 netif_carrier_on(phydev->attached_dev);
937 } else
938 phydev->state = PHY_NOLINK;
939 phydev->adjust_link(phydev->attached_dev);
940 } else {
941 phydev->state = PHY_AN;
942 phydev->link_timeout = PHY_AN_TIMEOUT;
943 }
944 } else {
945 err = phy_read_status(phydev);
946 if (err)
947 break;
948
949 if (phydev->link) {
950 phydev->state = PHY_RUNNING;
951 netif_carrier_on(phydev->attached_dev);
952 } else
953 phydev->state = PHY_NOLINK;
954 phydev->adjust_link(phydev->attached_dev);
955 }
956 break;
957 }
958
959 mutex_unlock(&phydev->lock);
960
961 if (needs_aneg)
962 err = phy_start_aneg(phydev);
963
964 if (err < 0)
965 phy_error(phydev);
966
967 schedule_delayed_work(&phydev->state_queue, PHY_STATE_TIME * HZ);
968 }
969