xref: /linux/drivers/net/phy/phy.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
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 
19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 
21 #include <linux/kernel.h>
22 #include <linux/string.h>
23 #include <linux/errno.h>
24 #include <linux/unistd.h>
25 #include <linux/interrupt.h>
26 #include <linux/init.h>
27 #include <linux/delay.h>
28 #include <linux/netdevice.h>
29 #include <linux/etherdevice.h>
30 #include <linux/skbuff.h>
31 #include <linux/mm.h>
32 #include <linux/module.h>
33 #include <linux/mii.h>
34 #include <linux/ethtool.h>
35 #include <linux/phy.h>
36 #include <linux/timer.h>
37 #include <linux/workqueue.h>
38 #include <linux/mdio.h>
39 
40 #include <linux/atomic.h>
41 #include <asm/io.h>
42 #include <asm/irq.h>
43 #include <asm/uaccess.h>
44 
45 /**
46  * phy_print_status - Convenience function to print out the current phy status
47  * @phydev: the phy_device struct
48  */
49 void phy_print_status(struct phy_device *phydev)
50 {
51 	if (phydev->link)
52 		pr_info("%s - Link is Up - %d/%s\n",
53 			dev_name(&phydev->dev),
54 			phydev->speed,
55 			DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
56 	else
57 		pr_info("%s - Link is Down\n", dev_name(&phydev->dev));
58 }
59 EXPORT_SYMBOL(phy_print_status);
60 
61 /**
62  * phy_clear_interrupt - Ack the phy device's interrupt
63  * @phydev: the phy_device struct
64  *
65  * If the @phydev driver has an ack_interrupt function, call it to
66  * ack and clear the phy device's interrupt.
67  *
68  * Returns 0 on success on < 0 on error.
69  */
70 static int phy_clear_interrupt(struct phy_device *phydev)
71 {
72 	int err = 0;
73 
74 	if (phydev->drv->ack_interrupt)
75 		err = phydev->drv->ack_interrupt(phydev);
76 
77 	return err;
78 }
79 
80 /**
81  * phy_config_interrupt - configure the PHY device for the requested interrupts
82  * @phydev: the phy_device struct
83  * @interrupts: interrupt flags to configure for this @phydev
84  *
85  * Returns 0 on success on < 0 on error.
86  */
87 static int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
88 {
89 	int err = 0;
90 
91 	phydev->interrupts = interrupts;
92 	if (phydev->drv->config_intr)
93 		err = phydev->drv->config_intr(phydev);
94 
95 	return err;
96 }
97 
98 
99 /**
100  * phy_aneg_done - return auto-negotiation status
101  * @phydev: target phy_device struct
102  *
103  * Description: Reads the status register and returns 0 either if
104  *   auto-negotiation is incomplete, or if there was an error.
105  *   Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
106  */
107 static inline int phy_aneg_done(struct phy_device *phydev)
108 {
109 	int retval;
110 
111 	retval = phy_read(phydev, MII_BMSR);
112 
113 	return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
114 }
115 
116 /* A structure for mapping a particular speed and duplex
117  * combination to a particular SUPPORTED and ADVERTISED value */
118 struct phy_setting {
119 	int speed;
120 	int duplex;
121 	u32 setting;
122 };
123 
124 /* A mapping of all SUPPORTED settings to speed/duplex */
125 static const struct phy_setting settings[] = {
126 	{
127 		.speed = 10000,
128 		.duplex = DUPLEX_FULL,
129 		.setting = SUPPORTED_10000baseT_Full,
130 	},
131 	{
132 		.speed = SPEED_1000,
133 		.duplex = DUPLEX_FULL,
134 		.setting = SUPPORTED_1000baseT_Full,
135 	},
136 	{
137 		.speed = SPEED_1000,
138 		.duplex = DUPLEX_HALF,
139 		.setting = SUPPORTED_1000baseT_Half,
140 	},
141 	{
142 		.speed = SPEED_100,
143 		.duplex = DUPLEX_FULL,
144 		.setting = SUPPORTED_100baseT_Full,
145 	},
146 	{
147 		.speed = SPEED_100,
148 		.duplex = DUPLEX_HALF,
149 		.setting = SUPPORTED_100baseT_Half,
150 	},
151 	{
152 		.speed = SPEED_10,
153 		.duplex = DUPLEX_FULL,
154 		.setting = SUPPORTED_10baseT_Full,
155 	},
156 	{
157 		.speed = SPEED_10,
158 		.duplex = DUPLEX_HALF,
159 		.setting = SUPPORTED_10baseT_Half,
160 	},
161 };
162 
163 #define MAX_NUM_SETTINGS ARRAY_SIZE(settings)
164 
165 /**
166  * phy_find_setting - find a PHY settings array entry that matches speed & duplex
167  * @speed: speed to match
168  * @duplex: duplex to match
169  *
170  * Description: Searches the settings array for the setting which
171  *   matches the desired speed and duplex, and returns the index
172  *   of that setting.  Returns the index of the last setting if
173  *   none of the others match.
174  */
175 static inline int phy_find_setting(int speed, int duplex)
176 {
177 	int idx = 0;
178 
179 	while (idx < ARRAY_SIZE(settings) &&
180 			(settings[idx].speed != speed ||
181 			settings[idx].duplex != duplex))
182 		idx++;
183 
184 	return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
185 }
186 
187 /**
188  * phy_find_valid - find a PHY setting that matches the requested features mask
189  * @idx: The first index in settings[] to search
190  * @features: A mask of the valid settings
191  *
192  * Description: Returns the index of the first valid setting less
193  *   than or equal to the one pointed to by idx, as determined by
194  *   the mask in features.  Returns the index of the last setting
195  *   if nothing else matches.
196  */
197 static inline int phy_find_valid(int idx, u32 features)
198 {
199 	while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
200 		idx++;
201 
202 	return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
203 }
204 
205 /**
206  * phy_sanitize_settings - make sure the PHY is set to supported speed and duplex
207  * @phydev: the target phy_device struct
208  *
209  * Description: Make sure the PHY is set to supported speeds and
210  *   duplexes.  Drop down by one in this order:  1000/FULL,
211  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
212  */
213 static void phy_sanitize_settings(struct phy_device *phydev)
214 {
215 	u32 features = phydev->supported;
216 	int idx;
217 
218 	/* Sanitize settings based on PHY capabilities */
219 	if ((features & SUPPORTED_Autoneg) == 0)
220 		phydev->autoneg = AUTONEG_DISABLE;
221 
222 	idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
223 			features);
224 
225 	phydev->speed = settings[idx].speed;
226 	phydev->duplex = settings[idx].duplex;
227 }
228 
229 /**
230  * phy_ethtool_sset - generic ethtool sset function, handles all the details
231  * @phydev: target phy_device struct
232  * @cmd: ethtool_cmd
233  *
234  * A few notes about parameter checking:
235  * - We don't set port or transceiver, so we don't care what they
236  *   were set to.
237  * - phy_start_aneg() will make sure forced settings are sane, and
238  *   choose the next best ones from the ones selected, so we don't
239  *   care if ethtool tries to give us bad values.
240  */
241 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
242 {
243 	u32 speed = ethtool_cmd_speed(cmd);
244 
245 	if (cmd->phy_address != phydev->addr)
246 		return -EINVAL;
247 
248 	/* We make sure that we don't pass unsupported
249 	 * values in to the PHY */
250 	cmd->advertising &= phydev->supported;
251 
252 	/* Verify the settings we care about. */
253 	if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
254 		return -EINVAL;
255 
256 	if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
257 		return -EINVAL;
258 
259 	if (cmd->autoneg == AUTONEG_DISABLE &&
260 	    ((speed != SPEED_1000 &&
261 	      speed != SPEED_100 &&
262 	      speed != SPEED_10) ||
263 	     (cmd->duplex != DUPLEX_HALF &&
264 	      cmd->duplex != DUPLEX_FULL)))
265 		return -EINVAL;
266 
267 	phydev->autoneg = cmd->autoneg;
268 
269 	phydev->speed = speed;
270 
271 	phydev->advertising = cmd->advertising;
272 
273 	if (AUTONEG_ENABLE == cmd->autoneg)
274 		phydev->advertising |= ADVERTISED_Autoneg;
275 	else
276 		phydev->advertising &= ~ADVERTISED_Autoneg;
277 
278 	phydev->duplex = cmd->duplex;
279 
280 	/* Restart the PHY */
281 	phy_start_aneg(phydev);
282 
283 	return 0;
284 }
285 EXPORT_SYMBOL(phy_ethtool_sset);
286 
287 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
288 {
289 	cmd->supported = phydev->supported;
290 
291 	cmd->advertising = phydev->advertising;
292 
293 	ethtool_cmd_speed_set(cmd, phydev->speed);
294 	cmd->duplex = phydev->duplex;
295 	cmd->port = PORT_MII;
296 	cmd->phy_address = phydev->addr;
297 	cmd->transceiver = XCVR_EXTERNAL;
298 	cmd->autoneg = phydev->autoneg;
299 
300 	return 0;
301 }
302 EXPORT_SYMBOL(phy_ethtool_gset);
303 
304 /**
305  * phy_mii_ioctl - generic PHY MII ioctl interface
306  * @phydev: the phy_device struct
307  * @ifr: &struct ifreq for socket ioctl's
308  * @cmd: ioctl cmd to execute
309  *
310  * Note that this function is currently incompatible with the
311  * PHYCONTROL layer.  It changes registers without regard to
312  * current state.  Use at own risk.
313  */
314 int phy_mii_ioctl(struct phy_device *phydev,
315 		struct ifreq *ifr, int cmd)
316 {
317 	struct mii_ioctl_data *mii_data = if_mii(ifr);
318 	u16 val = mii_data->val_in;
319 
320 	switch (cmd) {
321 	case SIOCGMIIPHY:
322 		mii_data->phy_id = phydev->addr;
323 		/* fall through */
324 
325 	case SIOCGMIIREG:
326 		mii_data->val_out = mdiobus_read(phydev->bus, mii_data->phy_id,
327 						 mii_data->reg_num);
328 		break;
329 
330 	case SIOCSMIIREG:
331 		if (mii_data->phy_id == phydev->addr) {
332 			switch(mii_data->reg_num) {
333 			case MII_BMCR:
334 				if ((val & (BMCR_RESET|BMCR_ANENABLE)) == 0)
335 					phydev->autoneg = AUTONEG_DISABLE;
336 				else
337 					phydev->autoneg = AUTONEG_ENABLE;
338 				if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
339 					phydev->duplex = DUPLEX_FULL;
340 				else
341 					phydev->duplex = DUPLEX_HALF;
342 				if ((!phydev->autoneg) &&
343 						(val & BMCR_SPEED1000))
344 					phydev->speed = SPEED_1000;
345 				else if ((!phydev->autoneg) &&
346 						(val & BMCR_SPEED100))
347 					phydev->speed = SPEED_100;
348 				break;
349 			case MII_ADVERTISE:
350 				phydev->advertising = val;
351 				break;
352 			default:
353 				/* do nothing */
354 				break;
355 			}
356 		}
357 
358 		mdiobus_write(phydev->bus, mii_data->phy_id,
359 			      mii_data->reg_num, val);
360 
361 		if (mii_data->reg_num == MII_BMCR &&
362 		    val & BMCR_RESET &&
363 		    phydev->drv->config_init) {
364 			phy_scan_fixups(phydev);
365 			phydev->drv->config_init(phydev);
366 		}
367 		break;
368 
369 	case SIOCSHWTSTAMP:
370 		if (phydev->drv->hwtstamp)
371 			return phydev->drv->hwtstamp(phydev, ifr);
372 		/* fall through */
373 
374 	default:
375 		return -EOPNOTSUPP;
376 	}
377 
378 	return 0;
379 }
380 EXPORT_SYMBOL(phy_mii_ioctl);
381 
382 /**
383  * phy_start_aneg - start auto-negotiation for this PHY device
384  * @phydev: the phy_device struct
385  *
386  * Description: Sanitizes the settings (if we're not autonegotiating
387  *   them), and then calls the driver's config_aneg function.
388  *   If the PHYCONTROL Layer is operating, we change the state to
389  *   reflect the beginning of Auto-negotiation or forcing.
390  */
391 int phy_start_aneg(struct phy_device *phydev)
392 {
393 	int err;
394 
395 	mutex_lock(&phydev->lock);
396 
397 	if (AUTONEG_DISABLE == phydev->autoneg)
398 		phy_sanitize_settings(phydev);
399 
400 	err = phydev->drv->config_aneg(phydev);
401 
402 	if (err < 0)
403 		goto out_unlock;
404 
405 	if (phydev->state != PHY_HALTED) {
406 		if (AUTONEG_ENABLE == phydev->autoneg) {
407 			phydev->state = PHY_AN;
408 			phydev->link_timeout = PHY_AN_TIMEOUT;
409 		} else {
410 			phydev->state = PHY_FORCING;
411 			phydev->link_timeout = PHY_FORCE_TIMEOUT;
412 		}
413 	}
414 
415 out_unlock:
416 	mutex_unlock(&phydev->lock);
417 	return err;
418 }
419 EXPORT_SYMBOL(phy_start_aneg);
420 
421 
422 static void phy_change(struct work_struct *work);
423 
424 /**
425  * phy_start_machine - start PHY state machine tracking
426  * @phydev: the phy_device struct
427  * @handler: callback function for state change notifications
428  *
429  * Description: The PHY infrastructure can run a state machine
430  *   which tracks whether the PHY is starting up, negotiating,
431  *   etc.  This function starts the timer which tracks the state
432  *   of the PHY.  If you want to be notified when the state changes,
433  *   pass in the callback @handler, otherwise, pass NULL.  If you
434  *   want to maintain your own state machine, do not call this
435  *   function.
436  */
437 void phy_start_machine(struct phy_device *phydev,
438 		void (*handler)(struct net_device *))
439 {
440 	phydev->adjust_state = handler;
441 
442 	schedule_delayed_work(&phydev->state_queue, HZ);
443 }
444 
445 /**
446  * phy_stop_machine - stop the PHY state machine tracking
447  * @phydev: target phy_device struct
448  *
449  * Description: Stops the state machine timer, sets the state to UP
450  *   (unless it wasn't up yet). This function must be called BEFORE
451  *   phy_detach.
452  */
453 void phy_stop_machine(struct phy_device *phydev)
454 {
455 	cancel_delayed_work_sync(&phydev->state_queue);
456 
457 	mutex_lock(&phydev->lock);
458 	if (phydev->state > PHY_UP)
459 		phydev->state = PHY_UP;
460 	mutex_unlock(&phydev->lock);
461 
462 	phydev->adjust_state = NULL;
463 }
464 
465 /**
466  * phy_force_reduction - reduce PHY speed/duplex settings by one step
467  * @phydev: target phy_device struct
468  *
469  * Description: Reduces the speed/duplex settings by one notch,
470  *   in this order--
471  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
472  *   The function bottoms out at 10/HALF.
473  */
474 static void phy_force_reduction(struct phy_device *phydev)
475 {
476 	int idx;
477 
478 	idx = phy_find_setting(phydev->speed, phydev->duplex);
479 
480 	idx++;
481 
482 	idx = phy_find_valid(idx, phydev->supported);
483 
484 	phydev->speed = settings[idx].speed;
485 	phydev->duplex = settings[idx].duplex;
486 
487 	pr_info("Trying %d/%s\n",
488 		phydev->speed, DUPLEX_FULL == phydev->duplex ? "FULL" : "HALF");
489 }
490 
491 
492 /**
493  * phy_error - enter HALTED state for this PHY device
494  * @phydev: target phy_device struct
495  *
496  * Moves the PHY to the HALTED state in response to a read
497  * or write error, and tells the controller the link is down.
498  * Must not be called from interrupt context, or while the
499  * phydev->lock is held.
500  */
501 static void phy_error(struct phy_device *phydev)
502 {
503 	mutex_lock(&phydev->lock);
504 	phydev->state = PHY_HALTED;
505 	mutex_unlock(&phydev->lock);
506 }
507 
508 /**
509  * phy_interrupt - PHY interrupt handler
510  * @irq: interrupt line
511  * @phy_dat: phy_device pointer
512  *
513  * Description: When a PHY interrupt occurs, the handler disables
514  * interrupts, and schedules a work task to clear the interrupt.
515  */
516 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
517 {
518 	struct phy_device *phydev = phy_dat;
519 
520 	if (PHY_HALTED == phydev->state)
521 		return IRQ_NONE;		/* It can't be ours.  */
522 
523 	/* The MDIO bus is not allowed to be written in interrupt
524 	 * context, so we need to disable the irq here.  A work
525 	 * queue will write the PHY to disable and clear the
526 	 * interrupt, and then reenable the irq line. */
527 	disable_irq_nosync(irq);
528 	atomic_inc(&phydev->irq_disable);
529 
530 	schedule_work(&phydev->phy_queue);
531 
532 	return IRQ_HANDLED;
533 }
534 
535 /**
536  * phy_enable_interrupts - Enable the interrupts from the PHY side
537  * @phydev: target phy_device struct
538  */
539 static int phy_enable_interrupts(struct phy_device *phydev)
540 {
541 	int err;
542 
543 	err = phy_clear_interrupt(phydev);
544 
545 	if (err < 0)
546 		return err;
547 
548 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
549 
550 	return err;
551 }
552 
553 /**
554  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
555  * @phydev: target phy_device struct
556  */
557 static int phy_disable_interrupts(struct phy_device *phydev)
558 {
559 	int err;
560 
561 	/* Disable PHY interrupts */
562 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
563 
564 	if (err)
565 		goto phy_err;
566 
567 	/* Clear the interrupt */
568 	err = phy_clear_interrupt(phydev);
569 
570 	if (err)
571 		goto phy_err;
572 
573 	return 0;
574 
575 phy_err:
576 	phy_error(phydev);
577 
578 	return err;
579 }
580 
581 /**
582  * phy_start_interrupts - request and enable interrupts for a PHY device
583  * @phydev: target phy_device struct
584  *
585  * Description: Request the interrupt for the given PHY.
586  *   If this fails, then we set irq to PHY_POLL.
587  *   Otherwise, we enable the interrupts in the PHY.
588  *   This should only be called with a valid IRQ number.
589  *   Returns 0 on success or < 0 on error.
590  */
591 int phy_start_interrupts(struct phy_device *phydev)
592 {
593 	int err = 0;
594 
595 	INIT_WORK(&phydev->phy_queue, phy_change);
596 
597 	atomic_set(&phydev->irq_disable, 0);
598 	if (request_irq(phydev->irq, phy_interrupt,
599 				IRQF_SHARED,
600 				"phy_interrupt",
601 				phydev) < 0) {
602 		pr_warn("%s: Can't get IRQ %d (PHY)\n",
603 			phydev->bus->name, phydev->irq);
604 		phydev->irq = PHY_POLL;
605 		return 0;
606 	}
607 
608 	err = phy_enable_interrupts(phydev);
609 
610 	return err;
611 }
612 EXPORT_SYMBOL(phy_start_interrupts);
613 
614 /**
615  * phy_stop_interrupts - disable interrupts from a PHY device
616  * @phydev: target phy_device struct
617  */
618 int phy_stop_interrupts(struct phy_device *phydev)
619 {
620 	int err;
621 
622 	err = phy_disable_interrupts(phydev);
623 
624 	if (err)
625 		phy_error(phydev);
626 
627 	free_irq(phydev->irq, phydev);
628 
629 	/*
630 	 * Cannot call flush_scheduled_work() here as desired because
631 	 * of rtnl_lock(), but we do not really care about what would
632 	 * be done, except from enable_irq(), so cancel any work
633 	 * possibly pending and take care of the matter below.
634 	 */
635 	cancel_work_sync(&phydev->phy_queue);
636 	/*
637 	 * If work indeed has been cancelled, disable_irq() will have
638 	 * been left unbalanced from phy_interrupt() and enable_irq()
639 	 * has to be called so that other devices on the line work.
640 	 */
641 	while (atomic_dec_return(&phydev->irq_disable) >= 0)
642 		enable_irq(phydev->irq);
643 
644 	return err;
645 }
646 EXPORT_SYMBOL(phy_stop_interrupts);
647 
648 
649 /**
650  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
651  * @work: work_struct that describes the work to be done
652  */
653 static void phy_change(struct work_struct *work)
654 {
655 	int err;
656 	struct phy_device *phydev =
657 		container_of(work, struct phy_device, phy_queue);
658 
659 	if (phydev->drv->did_interrupt &&
660 	    !phydev->drv->did_interrupt(phydev))
661 		goto ignore;
662 
663 	err = phy_disable_interrupts(phydev);
664 
665 	if (err)
666 		goto phy_err;
667 
668 	mutex_lock(&phydev->lock);
669 	if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
670 		phydev->state = PHY_CHANGELINK;
671 	mutex_unlock(&phydev->lock);
672 
673 	atomic_dec(&phydev->irq_disable);
674 	enable_irq(phydev->irq);
675 
676 	/* Reenable interrupts */
677 	if (PHY_HALTED != phydev->state)
678 		err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
679 
680 	if (err)
681 		goto irq_enable_err;
682 
683 	/* reschedule state queue work to run as soon as possible */
684 	cancel_delayed_work_sync(&phydev->state_queue);
685 	schedule_delayed_work(&phydev->state_queue, 0);
686 
687 	return;
688 
689 ignore:
690 	atomic_dec(&phydev->irq_disable);
691 	enable_irq(phydev->irq);
692 	return;
693 
694 irq_enable_err:
695 	disable_irq(phydev->irq);
696 	atomic_inc(&phydev->irq_disable);
697 phy_err:
698 	phy_error(phydev);
699 }
700 
701 /**
702  * phy_stop - Bring down the PHY link, and stop checking the status
703  * @phydev: target phy_device struct
704  */
705 void phy_stop(struct phy_device *phydev)
706 {
707 	mutex_lock(&phydev->lock);
708 
709 	if (PHY_HALTED == phydev->state)
710 		goto out_unlock;
711 
712 	if (phydev->irq != PHY_POLL) {
713 		/* Disable PHY Interrupts */
714 		phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
715 
716 		/* Clear any pending interrupts */
717 		phy_clear_interrupt(phydev);
718 	}
719 
720 	phydev->state = PHY_HALTED;
721 
722 out_unlock:
723 	mutex_unlock(&phydev->lock);
724 
725 	/*
726 	 * Cannot call flush_scheduled_work() here as desired because
727 	 * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
728 	 * will not reenable interrupts.
729 	 */
730 }
731 
732 
733 /**
734  * phy_start - start or restart a PHY device
735  * @phydev: target phy_device struct
736  *
737  * Description: Indicates the attached device's readiness to
738  *   handle PHY-related work.  Used during startup to start the
739  *   PHY, and after a call to phy_stop() to resume operation.
740  *   Also used to indicate the MDIO bus has cleared an error
741  *   condition.
742  */
743 void phy_start(struct phy_device *phydev)
744 {
745 	mutex_lock(&phydev->lock);
746 
747 	switch (phydev->state) {
748 		case PHY_STARTING:
749 			phydev->state = PHY_PENDING;
750 			break;
751 		case PHY_READY:
752 			phydev->state = PHY_UP;
753 			break;
754 		case PHY_HALTED:
755 			phydev->state = PHY_RESUMING;
756 		default:
757 			break;
758 	}
759 	mutex_unlock(&phydev->lock);
760 }
761 EXPORT_SYMBOL(phy_stop);
762 EXPORT_SYMBOL(phy_start);
763 
764 /**
765  * phy_state_machine - Handle the state machine
766  * @work: work_struct that describes the work to be done
767  */
768 void phy_state_machine(struct work_struct *work)
769 {
770 	struct delayed_work *dwork = to_delayed_work(work);
771 	struct phy_device *phydev =
772 			container_of(dwork, struct phy_device, state_queue);
773 	int needs_aneg = 0;
774 	int err = 0;
775 
776 	mutex_lock(&phydev->lock);
777 
778 	if (phydev->adjust_state)
779 		phydev->adjust_state(phydev->attached_dev);
780 
781 	switch(phydev->state) {
782 		case PHY_DOWN:
783 		case PHY_STARTING:
784 		case PHY_READY:
785 		case PHY_PENDING:
786 			break;
787 		case PHY_UP:
788 			needs_aneg = 1;
789 
790 			phydev->link_timeout = PHY_AN_TIMEOUT;
791 
792 			break;
793 		case PHY_AN:
794 			err = phy_read_status(phydev);
795 
796 			if (err < 0)
797 				break;
798 
799 			/* If the link is down, give up on
800 			 * negotiation for now */
801 			if (!phydev->link) {
802 				phydev->state = PHY_NOLINK;
803 				netif_carrier_off(phydev->attached_dev);
804 				phydev->adjust_link(phydev->attached_dev);
805 				break;
806 			}
807 
808 			/* Check if negotiation is done.  Break
809 			 * if there's an error */
810 			err = phy_aneg_done(phydev);
811 			if (err < 0)
812 				break;
813 
814 			/* If AN is done, we're running */
815 			if (err > 0) {
816 				phydev->state = PHY_RUNNING;
817 				netif_carrier_on(phydev->attached_dev);
818 				phydev->adjust_link(phydev->attached_dev);
819 
820 			} else if (0 == phydev->link_timeout--) {
821 				int idx;
822 
823 				needs_aneg = 1;
824 				/* If we have the magic_aneg bit,
825 				 * we try again */
826 				if (phydev->drv->flags & PHY_HAS_MAGICANEG)
827 					break;
828 
829 				/* The timer expired, and we still
830 				 * don't have a setting, so we try
831 				 * forcing it until we find one that
832 				 * works, starting from the fastest speed,
833 				 * and working our way down */
834 				idx = phy_find_valid(0, phydev->supported);
835 
836 				phydev->speed = settings[idx].speed;
837 				phydev->duplex = settings[idx].duplex;
838 
839 				phydev->autoneg = AUTONEG_DISABLE;
840 
841 				pr_info("Trying %d/%s\n",
842 					phydev->speed,
843 					DUPLEX_FULL == phydev->duplex ?
844 					"FULL" : "HALF");
845 			}
846 			break;
847 		case PHY_NOLINK:
848 			err = phy_read_status(phydev);
849 
850 			if (err)
851 				break;
852 
853 			if (phydev->link) {
854 				phydev->state = PHY_RUNNING;
855 				netif_carrier_on(phydev->attached_dev);
856 				phydev->adjust_link(phydev->attached_dev);
857 			}
858 			break;
859 		case PHY_FORCING:
860 			err = genphy_update_link(phydev);
861 
862 			if (err)
863 				break;
864 
865 			if (phydev->link) {
866 				phydev->state = PHY_RUNNING;
867 				netif_carrier_on(phydev->attached_dev);
868 			} else {
869 				if (0 == phydev->link_timeout--) {
870 					phy_force_reduction(phydev);
871 					needs_aneg = 1;
872 				}
873 			}
874 
875 			phydev->adjust_link(phydev->attached_dev);
876 			break;
877 		case PHY_RUNNING:
878 			/* Only register a CHANGE if we are
879 			 * polling */
880 			if (PHY_POLL == phydev->irq)
881 				phydev->state = PHY_CHANGELINK;
882 			break;
883 		case PHY_CHANGELINK:
884 			err = phy_read_status(phydev);
885 
886 			if (err)
887 				break;
888 
889 			if (phydev->link) {
890 				phydev->state = PHY_RUNNING;
891 				netif_carrier_on(phydev->attached_dev);
892 			} else {
893 				phydev->state = PHY_NOLINK;
894 				netif_carrier_off(phydev->attached_dev);
895 			}
896 
897 			phydev->adjust_link(phydev->attached_dev);
898 
899 			if (PHY_POLL != phydev->irq)
900 				err = phy_config_interrupt(phydev,
901 						PHY_INTERRUPT_ENABLED);
902 			break;
903 		case PHY_HALTED:
904 			if (phydev->link) {
905 				phydev->link = 0;
906 				netif_carrier_off(phydev->attached_dev);
907 				phydev->adjust_link(phydev->attached_dev);
908 			}
909 			break;
910 		case PHY_RESUMING:
911 
912 			err = phy_clear_interrupt(phydev);
913 
914 			if (err)
915 				break;
916 
917 			err = phy_config_interrupt(phydev,
918 					PHY_INTERRUPT_ENABLED);
919 
920 			if (err)
921 				break;
922 
923 			if (AUTONEG_ENABLE == phydev->autoneg) {
924 				err = phy_aneg_done(phydev);
925 				if (err < 0)
926 					break;
927 
928 				/* err > 0 if AN is done.
929 				 * Otherwise, it's 0, and we're
930 				 * still waiting for AN */
931 				if (err > 0) {
932 					err = phy_read_status(phydev);
933 					if (err)
934 						break;
935 
936 					if (phydev->link) {
937 						phydev->state = PHY_RUNNING;
938 						netif_carrier_on(phydev->attached_dev);
939 					} else
940 						phydev->state = PHY_NOLINK;
941 					phydev->adjust_link(phydev->attached_dev);
942 				} else {
943 					phydev->state = PHY_AN;
944 					phydev->link_timeout = PHY_AN_TIMEOUT;
945 				}
946 			} else {
947 				err = phy_read_status(phydev);
948 				if (err)
949 					break;
950 
951 				if (phydev->link) {
952 					phydev->state = PHY_RUNNING;
953 					netif_carrier_on(phydev->attached_dev);
954 				} else
955 					phydev->state = PHY_NOLINK;
956 				phydev->adjust_link(phydev->attached_dev);
957 			}
958 			break;
959 	}
960 
961 	mutex_unlock(&phydev->lock);
962 
963 	if (needs_aneg)
964 		err = phy_start_aneg(phydev);
965 
966 	if (err < 0)
967 		phy_error(phydev);
968 
969 	schedule_delayed_work(&phydev->state_queue, PHY_STATE_TIME * HZ);
970 }
971 
972 static inline void mmd_phy_indirect(struct mii_bus *bus, int prtad, int devad,
973 				    int addr)
974 {
975 	/* Write the desired MMD Devad */
976 	bus->write(bus, addr, MII_MMD_CTRL, devad);
977 
978 	/* Write the desired MMD register address */
979 	bus->write(bus, addr, MII_MMD_DATA, prtad);
980 
981 	/* Select the Function : DATA with no post increment */
982 	bus->write(bus, addr, MII_MMD_CTRL, (devad | MII_MMD_CTRL_NOINCR));
983 }
984 
985 /**
986  * phy_read_mmd_indirect - reads data from the MMD registers
987  * @bus: the target MII bus
988  * @prtad: MMD Address
989  * @devad: MMD DEVAD
990  * @addr: PHY address on the MII bus
991  *
992  * Description: it reads data from the MMD registers (clause 22 to access to
993  * clause 45) of the specified phy address.
994  * To read these register we have:
995  * 1) Write reg 13 // DEVAD
996  * 2) Write reg 14 // MMD Address
997  * 3) Write reg 13 // MMD Data Command for MMD DEVAD
998  * 3) Read  reg 14 // Read MMD data
999  */
1000 static int phy_read_mmd_indirect(struct mii_bus *bus, int prtad, int devad,
1001 				 int addr)
1002 {
1003 	u32 ret;
1004 
1005 	mmd_phy_indirect(bus, prtad, devad, addr);
1006 
1007 	/* Read the content of the MMD's selected register */
1008 	ret = bus->read(bus, addr, MII_MMD_DATA);
1009 
1010 	return ret;
1011 }
1012 
1013 /**
1014  * phy_write_mmd_indirect - writes data to the MMD registers
1015  * @bus: the target MII bus
1016  * @prtad: MMD Address
1017  * @devad: MMD DEVAD
1018  * @addr: PHY address on the MII bus
1019  * @data: data to write in the MMD register
1020  *
1021  * Description: Write data from the MMD registers of the specified
1022  * phy address.
1023  * To write these register we have:
1024  * 1) Write reg 13 // DEVAD
1025  * 2) Write reg 14 // MMD Address
1026  * 3) Write reg 13 // MMD Data Command for MMD DEVAD
1027  * 3) Write reg 14 // Write MMD data
1028  */
1029 static void phy_write_mmd_indirect(struct mii_bus *bus, int prtad, int devad,
1030 				   int addr, u32 data)
1031 {
1032 	mmd_phy_indirect(bus, prtad, devad, addr);
1033 
1034 	/* Write the data into MMD's selected register */
1035 	bus->write(bus, addr, MII_MMD_DATA, data);
1036 }
1037 
1038 /**
1039  * phy_init_eee - init and check the EEE feature
1040  * @phydev: target phy_device struct
1041  * @clk_stop_enable: PHY may stop the clock during LPI
1042  *
1043  * Description: it checks if the Energy-Efficient Ethernet (EEE)
1044  * is supported by looking at the MMD registers 3.20 and 7.60/61
1045  * and it programs the MMD register 3.0 setting the "Clock stop enable"
1046  * bit if required.
1047  */
1048 int phy_init_eee(struct phy_device *phydev, bool clk_stop_enable)
1049 {
1050 	int ret = -EPROTONOSUPPORT;
1051 
1052 	/* According to 802.3az,the EEE is supported only in full duplex-mode.
1053 	 * Also EEE feature is active when core is operating with MII, GMII
1054 	 * or RGMII.
1055 	 */
1056 	if ((phydev->duplex == DUPLEX_FULL) &&
1057 	    ((phydev->interface == PHY_INTERFACE_MODE_MII) ||
1058 	    (phydev->interface == PHY_INTERFACE_MODE_GMII) ||
1059 	    (phydev->interface == PHY_INTERFACE_MODE_RGMII))) {
1060 		int eee_lp, eee_cap, eee_adv;
1061 		u32 lp, cap, adv;
1062 		int idx, status;
1063 
1064 		/* Read phy status to properly get the right settings */
1065 		status = phy_read_status(phydev);
1066 		if (status)
1067 			return status;
1068 
1069 		/* First check if the EEE ability is supported */
1070 		eee_cap = phy_read_mmd_indirect(phydev->bus, MDIO_PCS_EEE_ABLE,
1071 						MDIO_MMD_PCS, phydev->addr);
1072 		if (eee_cap < 0)
1073 			return eee_cap;
1074 
1075 		cap = mmd_eee_cap_to_ethtool_sup_t(eee_cap);
1076 		if (!cap)
1077 			goto eee_exit;
1078 
1079 		/* Check which link settings negotiated and verify it in
1080 		 * the EEE advertising registers.
1081 		 */
1082 		eee_lp = phy_read_mmd_indirect(phydev->bus, MDIO_AN_EEE_LPABLE,
1083 					       MDIO_MMD_AN, phydev->addr);
1084 		if (eee_lp < 0)
1085 			return eee_lp;
1086 
1087 		eee_adv = phy_read_mmd_indirect(phydev->bus, MDIO_AN_EEE_ADV,
1088 						MDIO_MMD_AN, phydev->addr);
1089 		if (eee_adv < 0)
1090 			return eee_adv;
1091 
1092 		adv = mmd_eee_adv_to_ethtool_adv_t(eee_adv);
1093 		lp = mmd_eee_adv_to_ethtool_adv_t(eee_lp);
1094 		idx = phy_find_setting(phydev->speed, phydev->duplex);
1095 		if ((lp & adv & settings[idx].setting))
1096 			goto eee_exit;
1097 
1098 		if (clk_stop_enable) {
1099 			/* Configure the PHY to stop receiving xMII
1100 			 * clock while it is signaling LPI.
1101 			 */
1102 			int val = phy_read_mmd_indirect(phydev->bus, MDIO_CTRL1,
1103 							MDIO_MMD_PCS,
1104 							phydev->addr);
1105 			if (val < 0)
1106 				return val;
1107 
1108 			val |= MDIO_PCS_CTRL1_CLKSTOP_EN;
1109 			phy_write_mmd_indirect(phydev->bus, MDIO_CTRL1,
1110 					       MDIO_MMD_PCS, phydev->addr, val);
1111 		}
1112 
1113 		ret = 0; /* EEE supported */
1114 	}
1115 
1116 eee_exit:
1117 	return ret;
1118 }
1119 EXPORT_SYMBOL(phy_init_eee);
1120 
1121 /**
1122  * phy_get_eee_err - report the EEE wake error count
1123  * @phydev: target phy_device struct
1124  *
1125  * Description: it is to report the number of time where the PHY
1126  * failed to complete its normal wake sequence.
1127  */
1128 int phy_get_eee_err(struct phy_device *phydev)
1129 {
1130 	return phy_read_mmd_indirect(phydev->bus, MDIO_PCS_EEE_WK_ERR,
1131 				     MDIO_MMD_PCS, phydev->addr);
1132 
1133 }
1134 EXPORT_SYMBOL(phy_get_eee_err);
1135 
1136 /**
1137  * phy_ethtool_get_eee - get EEE supported and status
1138  * @phydev: target phy_device struct
1139  * @data: ethtool_eee data
1140  *
1141  * Description: it reportes the Supported/Advertisement/LP Advertisement
1142  * capabilities.
1143  */
1144 int phy_ethtool_get_eee(struct phy_device *phydev, struct ethtool_eee *data)
1145 {
1146 	int val;
1147 
1148 	/* Get Supported EEE */
1149 	val = phy_read_mmd_indirect(phydev->bus, MDIO_PCS_EEE_ABLE,
1150 				    MDIO_MMD_PCS, phydev->addr);
1151 	if (val < 0)
1152 		return val;
1153 	data->supported = mmd_eee_cap_to_ethtool_sup_t(val);
1154 
1155 	/* Get advertisement EEE */
1156 	val = phy_read_mmd_indirect(phydev->bus, MDIO_AN_EEE_ADV,
1157 				    MDIO_MMD_AN, phydev->addr);
1158 	if (val < 0)
1159 		return val;
1160 	data->advertised = mmd_eee_adv_to_ethtool_adv_t(val);
1161 
1162 	/* Get LP advertisement EEE */
1163 	val = phy_read_mmd_indirect(phydev->bus, MDIO_AN_EEE_LPABLE,
1164 				    MDIO_MMD_AN, phydev->addr);
1165 	if (val < 0)
1166 		return val;
1167 	data->lp_advertised = mmd_eee_adv_to_ethtool_adv_t(val);
1168 
1169 	return 0;
1170 }
1171 EXPORT_SYMBOL(phy_ethtool_get_eee);
1172 
1173 /**
1174  * phy_ethtool_set_eee - set EEE supported and status
1175  * @phydev: target phy_device struct
1176  * @data: ethtool_eee data
1177  *
1178  * Description: it is to program the Advertisement EEE register.
1179  */
1180 int phy_ethtool_set_eee(struct phy_device *phydev, struct ethtool_eee *data)
1181 {
1182 	int val;
1183 
1184 	val = ethtool_adv_to_mmd_eee_adv_t(data->advertised);
1185 	phy_write_mmd_indirect(phydev->bus, MDIO_AN_EEE_ADV, MDIO_MMD_AN,
1186 			       phydev->addr, val);
1187 
1188 	return 0;
1189 }
1190 EXPORT_SYMBOL(phy_ethtool_set_eee);
1191