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 <linux/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 	u32 speed = ethtool_cmd_speed(cmd);
242 
243 	if (cmd->phy_address != phydev->addr)
244 		return -EINVAL;
245 
246 	/* We make sure that we don't pass unsupported
247 	 * values in to the PHY */
248 	cmd->advertising &= phydev->supported;
249 
250 	/* Verify the settings we care about. */
251 	if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
252 		return -EINVAL;
253 
254 	if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
255 		return -EINVAL;
256 
257 	if (cmd->autoneg == AUTONEG_DISABLE &&
258 	    ((speed != SPEED_1000 &&
259 	      speed != SPEED_100 &&
260 	      speed != SPEED_10) ||
261 	     (cmd->duplex != DUPLEX_HALF &&
262 	      cmd->duplex != DUPLEX_FULL)))
263 		return -EINVAL;
264 
265 	phydev->autoneg = cmd->autoneg;
266 
267 	phydev->speed = speed;
268 
269 	phydev->advertising = cmd->advertising;
270 
271 	if (AUTONEG_ENABLE == cmd->autoneg)
272 		phydev->advertising |= ADVERTISED_Autoneg;
273 	else
274 		phydev->advertising &= ~ADVERTISED_Autoneg;
275 
276 	phydev->duplex = cmd->duplex;
277 
278 	/* Restart the PHY */
279 	phy_start_aneg(phydev);
280 
281 	return 0;
282 }
283 EXPORT_SYMBOL(phy_ethtool_sset);
284 
phy_ethtool_gset(struct phy_device * phydev,struct ethtool_cmd * cmd)285 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
286 {
287 	cmd->supported = phydev->supported;
288 
289 	cmd->advertising = phydev->advertising;
290 
291 	ethtool_cmd_speed_set(cmd, phydev->speed);
292 	cmd->duplex = phydev->duplex;
293 	cmd->port = PORT_MII;
294 	cmd->phy_address = phydev->addr;
295 	cmd->transceiver = XCVR_EXTERNAL;
296 	cmd->autoneg = phydev->autoneg;
297 
298 	return 0;
299 }
300 EXPORT_SYMBOL(phy_ethtool_gset);
301 
302 /**
303  * phy_mii_ioctl - generic PHY MII ioctl interface
304  * @phydev: the phy_device struct
305  * @ifr: &struct ifreq for socket ioctl's
306  * @cmd: ioctl cmd to execute
307  *
308  * Note that this function is currently incompatible with the
309  * PHYCONTROL layer.  It changes registers without regard to
310  * current state.  Use at own risk.
311  */
phy_mii_ioctl(struct phy_device * phydev,struct ifreq * ifr,int cmd)312 int phy_mii_ioctl(struct phy_device *phydev,
313 		struct ifreq *ifr, int cmd)
314 {
315 	struct mii_ioctl_data *mii_data = if_mii(ifr);
316 	u16 val = mii_data->val_in;
317 
318 	switch (cmd) {
319 	case SIOCGMIIPHY:
320 		mii_data->phy_id = phydev->addr;
321 		/* fall through */
322 
323 	case SIOCGMIIREG:
324 		mii_data->val_out = mdiobus_read(phydev->bus, mii_data->phy_id,
325 						 mii_data->reg_num);
326 		break;
327 
328 	case SIOCSMIIREG:
329 		if (mii_data->phy_id == phydev->addr) {
330 			switch(mii_data->reg_num) {
331 			case MII_BMCR:
332 				if ((val & (BMCR_RESET|BMCR_ANENABLE)) == 0)
333 					phydev->autoneg = AUTONEG_DISABLE;
334 				else
335 					phydev->autoneg = AUTONEG_ENABLE;
336 				if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
337 					phydev->duplex = DUPLEX_FULL;
338 				else
339 					phydev->duplex = DUPLEX_HALF;
340 				if ((!phydev->autoneg) &&
341 						(val & BMCR_SPEED1000))
342 					phydev->speed = SPEED_1000;
343 				else if ((!phydev->autoneg) &&
344 						(val & BMCR_SPEED100))
345 					phydev->speed = SPEED_100;
346 				break;
347 			case MII_ADVERTISE:
348 				phydev->advertising = val;
349 				break;
350 			default:
351 				/* do nothing */
352 				break;
353 			}
354 		}
355 
356 		mdiobus_write(phydev->bus, mii_data->phy_id,
357 			      mii_data->reg_num, val);
358 
359 		if (mii_data->reg_num == MII_BMCR &&
360 		    val & BMCR_RESET &&
361 		    phydev->drv->config_init) {
362 			phy_scan_fixups(phydev);
363 			phydev->drv->config_init(phydev);
364 		}
365 		break;
366 
367 	case SIOCSHWTSTAMP:
368 		if (phydev->drv->hwtstamp)
369 			return phydev->drv->hwtstamp(phydev, ifr);
370 		/* fall through */
371 
372 	default:
373 		return -EOPNOTSUPP;
374 	}
375 
376 	return 0;
377 }
378 EXPORT_SYMBOL(phy_mii_ioctl);
379 
380 /**
381  * phy_start_aneg - start auto-negotiation for this PHY device
382  * @phydev: the phy_device struct
383  *
384  * Description: Sanitizes the settings (if we're not autonegotiating
385  *   them), and then calls the driver's config_aneg function.
386  *   If the PHYCONTROL Layer is operating, we change the state to
387  *   reflect the beginning of Auto-negotiation or forcing.
388  */
phy_start_aneg(struct phy_device * phydev)389 int phy_start_aneg(struct phy_device *phydev)
390 {
391 	int err;
392 
393 	mutex_lock(&phydev->lock);
394 
395 	if (AUTONEG_DISABLE == phydev->autoneg)
396 		phy_sanitize_settings(phydev);
397 
398 	err = phydev->drv->config_aneg(phydev);
399 
400 	if (err < 0)
401 		goto out_unlock;
402 
403 	if (phydev->state != PHY_HALTED) {
404 		if (AUTONEG_ENABLE == phydev->autoneg) {
405 			phydev->state = PHY_AN;
406 			phydev->link_timeout = PHY_AN_TIMEOUT;
407 		} else {
408 			phydev->state = PHY_FORCING;
409 			phydev->link_timeout = PHY_FORCE_TIMEOUT;
410 		}
411 	}
412 
413 out_unlock:
414 	mutex_unlock(&phydev->lock);
415 	return err;
416 }
417 EXPORT_SYMBOL(phy_start_aneg);
418 
419 
420 static void phy_change(struct work_struct *work);
421 
422 /**
423  * phy_start_machine - start PHY state machine tracking
424  * @phydev: the phy_device struct
425  * @handler: callback function for state change notifications
426  *
427  * Description: The PHY infrastructure can run a state machine
428  *   which tracks whether the PHY is starting up, negotiating,
429  *   etc.  This function starts the timer which tracks the state
430  *   of the PHY.  If you want to be notified when the state changes,
431  *   pass in the callback @handler, otherwise, pass NULL.  If you
432  *   want to maintain your own state machine, do not call this
433  *   function.
434  */
phy_start_machine(struct phy_device * phydev,void (* handler)(struct net_device *))435 void phy_start_machine(struct phy_device *phydev,
436 		void (*handler)(struct net_device *))
437 {
438 	phydev->adjust_state = handler;
439 
440 	schedule_delayed_work(&phydev->state_queue, HZ);
441 }
442 
443 /**
444  * phy_stop_machine - stop the PHY state machine tracking
445  * @phydev: target phy_device struct
446  *
447  * Description: Stops the state machine timer, sets the state to UP
448  *   (unless it wasn't up yet). This function must be called BEFORE
449  *   phy_detach.
450  */
phy_stop_machine(struct phy_device * phydev)451 void phy_stop_machine(struct phy_device *phydev)
452 {
453 	cancel_delayed_work_sync(&phydev->state_queue);
454 
455 	mutex_lock(&phydev->lock);
456 	if (phydev->state > PHY_UP)
457 		phydev->state = PHY_UP;
458 	mutex_unlock(&phydev->lock);
459 
460 	phydev->adjust_state = NULL;
461 }
462 
463 /**
464  * phy_force_reduction - reduce PHY speed/duplex settings by one step
465  * @phydev: target phy_device struct
466  *
467  * Description: Reduces the speed/duplex settings by one notch,
468  *   in this order--
469  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
470  *   The function bottoms out at 10/HALF.
471  */
phy_force_reduction(struct phy_device * phydev)472 static void phy_force_reduction(struct phy_device *phydev)
473 {
474 	int idx;
475 
476 	idx = phy_find_setting(phydev->speed, phydev->duplex);
477 
478 	idx++;
479 
480 	idx = phy_find_valid(idx, phydev->supported);
481 
482 	phydev->speed = settings[idx].speed;
483 	phydev->duplex = settings[idx].duplex;
484 
485 	pr_info("Trying %d/%s\n", phydev->speed,
486 			DUPLEX_FULL == phydev->duplex ?
487 			"FULL" : "HALF");
488 }
489 
490 
491 /**
492  * phy_error - enter HALTED state for this PHY device
493  * @phydev: target phy_device struct
494  *
495  * Moves the PHY to the HALTED state in response to a read
496  * or write error, and tells the controller the link is down.
497  * Must not be called from interrupt context, or while the
498  * phydev->lock is held.
499  */
phy_error(struct phy_device * phydev)500 static void phy_error(struct phy_device *phydev)
501 {
502 	mutex_lock(&phydev->lock);
503 	phydev->state = PHY_HALTED;
504 	mutex_unlock(&phydev->lock);
505 }
506 
507 /**
508  * phy_interrupt - PHY interrupt handler
509  * @irq: interrupt line
510  * @phy_dat: phy_device pointer
511  *
512  * Description: When a PHY interrupt occurs, the handler disables
513  * interrupts, and schedules a work task to clear the interrupt.
514  */
phy_interrupt(int irq,void * phy_dat)515 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
516 {
517 	struct phy_device *phydev = phy_dat;
518 
519 	if (PHY_HALTED == phydev->state)
520 		return IRQ_NONE;		/* It can't be ours.  */
521 
522 	/* The MDIO bus is not allowed to be written in interrupt
523 	 * context, so we need to disable the irq here.  A work
524 	 * queue will write the PHY to disable and clear the
525 	 * interrupt, and then reenable the irq line. */
526 	disable_irq_nosync(irq);
527 	atomic_inc(&phydev->irq_disable);
528 
529 	schedule_work(&phydev->phy_queue);
530 
531 	return IRQ_HANDLED;
532 }
533 
534 /**
535  * phy_enable_interrupts - Enable the interrupts from the PHY side
536  * @phydev: target phy_device struct
537  */
phy_enable_interrupts(struct phy_device * phydev)538 static int phy_enable_interrupts(struct phy_device *phydev)
539 {
540 	int err;
541 
542 	err = phy_clear_interrupt(phydev);
543 
544 	if (err < 0)
545 		return err;
546 
547 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
548 
549 	return err;
550 }
551 
552 /**
553  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
554  * @phydev: target phy_device struct
555  */
phy_disable_interrupts(struct phy_device * phydev)556 static int phy_disable_interrupts(struct phy_device *phydev)
557 {
558 	int err;
559 
560 	/* Disable PHY interrupts */
561 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
562 
563 	if (err)
564 		goto phy_err;
565 
566 	/* Clear the interrupt */
567 	err = phy_clear_interrupt(phydev);
568 
569 	if (err)
570 		goto phy_err;
571 
572 	return 0;
573 
574 phy_err:
575 	phy_error(phydev);
576 
577 	return err;
578 }
579 
580 /**
581  * phy_start_interrupts - request and enable interrupts for a PHY device
582  * @phydev: target phy_device struct
583  *
584  * Description: Request the interrupt for the given PHY.
585  *   If this fails, then we set irq to PHY_POLL.
586  *   Otherwise, we enable the interrupts in the PHY.
587  *   This should only be called with a valid IRQ number.
588  *   Returns 0 on success or < 0 on error.
589  */
phy_start_interrupts(struct phy_device * phydev)590 int phy_start_interrupts(struct phy_device *phydev)
591 {
592 	int err = 0;
593 
594 	INIT_WORK(&phydev->phy_queue, phy_change);
595 
596 	atomic_set(&phydev->irq_disable, 0);
597 	if (request_irq(phydev->irq, phy_interrupt,
598 				IRQF_SHARED,
599 				"phy_interrupt",
600 				phydev) < 0) {
601 		printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
602 				phydev->bus->name,
603 				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  */
phy_stop_interrupts(struct phy_device * phydev)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  */
phy_change(struct work_struct * work)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  */
phy_stop(struct phy_device * phydev)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  */
phy_start(struct phy_device * phydev)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  */
phy_state_machine(struct work_struct * work)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", phydev->speed,
842 						DUPLEX_FULL ==
843 						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