xref: /linux/drivers/net/phy/phy.c (revision 7bb377107c72a40ab7505341f8626c8eb79a0cb7)
1 // SPDX-License-Identifier: GPL-2.0+
2 /* Framework for configuring and reading PHY devices
3  * Based on code in sungem_phy.c and gianfar_phy.c
4  *
5  * Author: Andy Fleming
6  *
7  * Copyright (c) 2004 Freescale Semiconductor, Inc.
8  * Copyright (c) 2006, 2007  Maciej W. Rozycki
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/errno.h>
14 #include <linux/unistd.h>
15 #include <linux/interrupt.h>
16 #include <linux/delay.h>
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/skbuff.h>
20 #include <linux/mm.h>
21 #include <linux/module.h>
22 #include <linux/mii.h>
23 #include <linux/ethtool.h>
24 #include <linux/phy.h>
25 #include <linux/phy_led_triggers.h>
26 #include <linux/sfp.h>
27 #include <linux/workqueue.h>
28 #include <linux/mdio.h>
29 #include <linux/io.h>
30 #include <linux/uaccess.h>
31 #include <linux/atomic.h>
32 
33 #define PHY_STATE_TIME	HZ
34 
35 #define PHY_STATE_STR(_state)			\
36 	case PHY_##_state:			\
37 		return __stringify(_state);	\
38 
39 static const char *phy_state_to_str(enum phy_state st)
40 {
41 	switch (st) {
42 	PHY_STATE_STR(DOWN)
43 	PHY_STATE_STR(READY)
44 	PHY_STATE_STR(UP)
45 	PHY_STATE_STR(RUNNING)
46 	PHY_STATE_STR(NOLINK)
47 	PHY_STATE_STR(HALTED)
48 	}
49 
50 	return NULL;
51 }
52 
53 static void phy_link_up(struct phy_device *phydev)
54 {
55 	phydev->phy_link_change(phydev, true, true);
56 	phy_led_trigger_change_speed(phydev);
57 }
58 
59 static void phy_link_down(struct phy_device *phydev, bool do_carrier)
60 {
61 	phydev->phy_link_change(phydev, false, do_carrier);
62 	phy_led_trigger_change_speed(phydev);
63 }
64 
65 static const char *phy_pause_str(struct phy_device *phydev)
66 {
67 	bool local_pause, local_asym_pause;
68 
69 	if (phydev->autoneg == AUTONEG_DISABLE)
70 		goto no_pause;
71 
72 	local_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
73 					phydev->advertising);
74 	local_asym_pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Asym_Pause_BIT,
75 					     phydev->advertising);
76 
77 	if (local_pause && phydev->pause)
78 		return "rx/tx";
79 
80 	if (local_asym_pause && phydev->asym_pause) {
81 		if (local_pause)
82 			return "rx";
83 		if (phydev->pause)
84 			return "tx";
85 	}
86 
87 no_pause:
88 	return "off";
89 }
90 
91 /**
92  * phy_print_status - Convenience function to print out the current phy status
93  * @phydev: the phy_device struct
94  */
95 void phy_print_status(struct phy_device *phydev)
96 {
97 	if (phydev->link) {
98 		netdev_info(phydev->attached_dev,
99 			"Link is Up - %s/%s %s- flow control %s\n",
100 			phy_speed_to_str(phydev->speed),
101 			phy_duplex_to_str(phydev->duplex),
102 			phydev->downshifted_rate ? "(downshifted) " : "",
103 			phy_pause_str(phydev));
104 	} else	{
105 		netdev_info(phydev->attached_dev, "Link is Down\n");
106 	}
107 }
108 EXPORT_SYMBOL(phy_print_status);
109 
110 /**
111  * phy_clear_interrupt - Ack the phy device's interrupt
112  * @phydev: the phy_device struct
113  *
114  * If the @phydev driver has an ack_interrupt function, call it to
115  * ack and clear the phy device's interrupt.
116  *
117  * Returns 0 on success or < 0 on error.
118  */
119 static int phy_clear_interrupt(struct phy_device *phydev)
120 {
121 	if (phydev->drv->ack_interrupt)
122 		return phydev->drv->ack_interrupt(phydev);
123 
124 	return 0;
125 }
126 
127 /**
128  * phy_config_interrupt - configure the PHY device for the requested interrupts
129  * @phydev: the phy_device struct
130  * @interrupts: interrupt flags to configure for this @phydev
131  *
132  * Returns 0 on success or < 0 on error.
133  */
134 static int phy_config_interrupt(struct phy_device *phydev, bool interrupts)
135 {
136 	phydev->interrupts = interrupts ? 1 : 0;
137 	if (phydev->drv->config_intr)
138 		return phydev->drv->config_intr(phydev);
139 
140 	return 0;
141 }
142 
143 /**
144  * phy_restart_aneg - restart auto-negotiation
145  * @phydev: target phy_device struct
146  *
147  * Restart the autonegotiation on @phydev.  Returns >= 0 on success or
148  * negative errno on error.
149  */
150 int phy_restart_aneg(struct phy_device *phydev)
151 {
152 	int ret;
153 
154 	if (phydev->is_c45 && !(phydev->c45_ids.devices_in_package & BIT(0)))
155 		ret = genphy_c45_restart_aneg(phydev);
156 	else
157 		ret = genphy_restart_aneg(phydev);
158 
159 	return ret;
160 }
161 EXPORT_SYMBOL_GPL(phy_restart_aneg);
162 
163 /**
164  * phy_aneg_done - return auto-negotiation status
165  * @phydev: target phy_device struct
166  *
167  * Description: Return the auto-negotiation status from this @phydev
168  * Returns > 0 on success or < 0 on error. 0 means that auto-negotiation
169  * is still pending.
170  */
171 int phy_aneg_done(struct phy_device *phydev)
172 {
173 	if (phydev->drv && phydev->drv->aneg_done)
174 		return phydev->drv->aneg_done(phydev);
175 	else if (phydev->is_c45)
176 		return genphy_c45_aneg_done(phydev);
177 	else
178 		return genphy_aneg_done(phydev);
179 }
180 EXPORT_SYMBOL(phy_aneg_done);
181 
182 /**
183  * phy_find_valid - find a PHY setting that matches the requested parameters
184  * @speed: desired speed
185  * @duplex: desired duplex
186  * @supported: mask of supported link modes
187  *
188  * Locate a supported phy setting that is, in priority order:
189  * - an exact match for the specified speed and duplex mode
190  * - a match for the specified speed, or slower speed
191  * - the slowest supported speed
192  * Returns the matched phy_setting entry, or %NULL if no supported phy
193  * settings were found.
194  */
195 static const struct phy_setting *
196 phy_find_valid(int speed, int duplex, unsigned long *supported)
197 {
198 	return phy_lookup_setting(speed, duplex, supported, false);
199 }
200 
201 /**
202  * phy_supported_speeds - return all speeds currently supported by a phy device
203  * @phy: The phy device to return supported speeds of.
204  * @speeds: buffer to store supported speeds in.
205  * @size:   size of speeds buffer.
206  *
207  * Description: Returns the number of supported speeds, and fills the speeds
208  * buffer with the supported speeds. If speeds buffer is too small to contain
209  * all currently supported speeds, will return as many speeds as can fit.
210  */
211 unsigned int phy_supported_speeds(struct phy_device *phy,
212 				  unsigned int *speeds,
213 				  unsigned int size)
214 {
215 	return phy_speeds(speeds, size, phy->supported);
216 }
217 
218 /**
219  * phy_check_valid - check if there is a valid PHY setting which matches
220  *		     speed, duplex, and feature mask
221  * @speed: speed to match
222  * @duplex: duplex to match
223  * @features: A mask of the valid settings
224  *
225  * Description: Returns true if there is a valid setting, false otherwise.
226  */
227 static inline bool phy_check_valid(int speed, int duplex,
228 				   unsigned long *features)
229 {
230 	return !!phy_lookup_setting(speed, duplex, features, true);
231 }
232 
233 /**
234  * phy_sanitize_settings - make sure the PHY is set to supported speed and duplex
235  * @phydev: the target phy_device struct
236  *
237  * Description: Make sure the PHY is set to supported speeds and
238  *   duplexes.  Drop down by one in this order:  1000/FULL,
239  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
240  */
241 static void phy_sanitize_settings(struct phy_device *phydev)
242 {
243 	const struct phy_setting *setting;
244 
245 	setting = phy_find_valid(phydev->speed, phydev->duplex,
246 				 phydev->supported);
247 	if (setting) {
248 		phydev->speed = setting->speed;
249 		phydev->duplex = setting->duplex;
250 	} else {
251 		/* We failed to find anything (no supported speeds?) */
252 		phydev->speed = SPEED_UNKNOWN;
253 		phydev->duplex = DUPLEX_UNKNOWN;
254 	}
255 }
256 
257 int phy_ethtool_ksettings_set(struct phy_device *phydev,
258 			      const struct ethtool_link_ksettings *cmd)
259 {
260 	__ETHTOOL_DECLARE_LINK_MODE_MASK(advertising);
261 	u8 autoneg = cmd->base.autoneg;
262 	u8 duplex = cmd->base.duplex;
263 	u32 speed = cmd->base.speed;
264 
265 	if (cmd->base.phy_address != phydev->mdio.addr)
266 		return -EINVAL;
267 
268 	linkmode_copy(advertising, cmd->link_modes.advertising);
269 
270 	/* We make sure that we don't pass unsupported values in to the PHY */
271 	linkmode_and(advertising, advertising, phydev->supported);
272 
273 	/* Verify the settings we care about. */
274 	if (autoneg != AUTONEG_ENABLE && autoneg != AUTONEG_DISABLE)
275 		return -EINVAL;
276 
277 	if (autoneg == AUTONEG_ENABLE && linkmode_empty(advertising))
278 		return -EINVAL;
279 
280 	if (autoneg == AUTONEG_DISABLE &&
281 	    ((speed != SPEED_1000 &&
282 	      speed != SPEED_100 &&
283 	      speed != SPEED_10) ||
284 	     (duplex != DUPLEX_HALF &&
285 	      duplex != DUPLEX_FULL)))
286 		return -EINVAL;
287 
288 	phydev->autoneg = autoneg;
289 
290 	phydev->speed = speed;
291 
292 	linkmode_copy(phydev->advertising, advertising);
293 
294 	linkmode_mod_bit(ETHTOOL_LINK_MODE_Autoneg_BIT,
295 			 phydev->advertising, autoneg == AUTONEG_ENABLE);
296 
297 	phydev->duplex = duplex;
298 	phydev->master_slave_set = cmd->base.master_slave_cfg;
299 	phydev->mdix_ctrl = cmd->base.eth_tp_mdix_ctrl;
300 
301 	/* Restart the PHY */
302 	phy_start_aneg(phydev);
303 
304 	return 0;
305 }
306 EXPORT_SYMBOL(phy_ethtool_ksettings_set);
307 
308 void phy_ethtool_ksettings_get(struct phy_device *phydev,
309 			       struct ethtool_link_ksettings *cmd)
310 {
311 	linkmode_copy(cmd->link_modes.supported, phydev->supported);
312 	linkmode_copy(cmd->link_modes.advertising, phydev->advertising);
313 	linkmode_copy(cmd->link_modes.lp_advertising, phydev->lp_advertising);
314 
315 	cmd->base.speed = phydev->speed;
316 	cmd->base.duplex = phydev->duplex;
317 	cmd->base.master_slave_cfg = phydev->master_slave_get;
318 	cmd->base.master_slave_state = phydev->master_slave_state;
319 	if (phydev->interface == PHY_INTERFACE_MODE_MOCA)
320 		cmd->base.port = PORT_BNC;
321 	else
322 		cmd->base.port = PORT_MII;
323 	cmd->base.transceiver = phy_is_internal(phydev) ?
324 				XCVR_INTERNAL : XCVR_EXTERNAL;
325 	cmd->base.phy_address = phydev->mdio.addr;
326 	cmd->base.autoneg = phydev->autoneg;
327 	cmd->base.eth_tp_mdix_ctrl = phydev->mdix_ctrl;
328 	cmd->base.eth_tp_mdix = phydev->mdix;
329 }
330 EXPORT_SYMBOL(phy_ethtool_ksettings_get);
331 
332 /**
333  * phy_mii_ioctl - generic PHY MII ioctl interface
334  * @phydev: the phy_device struct
335  * @ifr: &struct ifreq for socket ioctl's
336  * @cmd: ioctl cmd to execute
337  *
338  * Note that this function is currently incompatible with the
339  * PHYCONTROL layer.  It changes registers without regard to
340  * current state.  Use at own risk.
341  */
342 int phy_mii_ioctl(struct phy_device *phydev, struct ifreq *ifr, int cmd)
343 {
344 	struct mii_ioctl_data *mii_data = if_mii(ifr);
345 	u16 val = mii_data->val_in;
346 	bool change_autoneg = false;
347 	int prtad, devad;
348 
349 	switch (cmd) {
350 	case SIOCGMIIPHY:
351 		mii_data->phy_id = phydev->mdio.addr;
352 		/* fall through */
353 
354 	case SIOCGMIIREG:
355 		if (mdio_phy_id_is_c45(mii_data->phy_id)) {
356 			prtad = mdio_phy_id_prtad(mii_data->phy_id);
357 			devad = mdio_phy_id_devad(mii_data->phy_id);
358 			devad = MII_ADDR_C45 | devad << 16 | mii_data->reg_num;
359 		} else {
360 			prtad = mii_data->phy_id;
361 			devad = mii_data->reg_num;
362 		}
363 		mii_data->val_out = mdiobus_read(phydev->mdio.bus, prtad,
364 						 devad);
365 		return 0;
366 
367 	case SIOCSMIIREG:
368 		if (mdio_phy_id_is_c45(mii_data->phy_id)) {
369 			prtad = mdio_phy_id_prtad(mii_data->phy_id);
370 			devad = mdio_phy_id_devad(mii_data->phy_id);
371 			devad = MII_ADDR_C45 | devad << 16 | mii_data->reg_num;
372 		} else {
373 			prtad = mii_data->phy_id;
374 			devad = mii_data->reg_num;
375 		}
376 		if (prtad == phydev->mdio.addr) {
377 			switch (devad) {
378 			case MII_BMCR:
379 				if ((val & (BMCR_RESET | BMCR_ANENABLE)) == 0) {
380 					if (phydev->autoneg == AUTONEG_ENABLE)
381 						change_autoneg = true;
382 					phydev->autoneg = AUTONEG_DISABLE;
383 					if (val & BMCR_FULLDPLX)
384 						phydev->duplex = DUPLEX_FULL;
385 					else
386 						phydev->duplex = DUPLEX_HALF;
387 					if (val & BMCR_SPEED1000)
388 						phydev->speed = SPEED_1000;
389 					else if (val & BMCR_SPEED100)
390 						phydev->speed = SPEED_100;
391 					else phydev->speed = SPEED_10;
392 				}
393 				else {
394 					if (phydev->autoneg == AUTONEG_DISABLE)
395 						change_autoneg = true;
396 					phydev->autoneg = AUTONEG_ENABLE;
397 				}
398 				break;
399 			case MII_ADVERTISE:
400 				mii_adv_mod_linkmode_adv_t(phydev->advertising,
401 							   val);
402 				change_autoneg = true;
403 				break;
404 			case MII_CTRL1000:
405 				mii_ctrl1000_mod_linkmode_adv_t(phydev->advertising,
406 							        val);
407 				change_autoneg = true;
408 				break;
409 			default:
410 				/* do nothing */
411 				break;
412 			}
413 		}
414 
415 		mdiobus_write(phydev->mdio.bus, prtad, devad, val);
416 
417 		if (prtad == phydev->mdio.addr &&
418 		    devad == MII_BMCR &&
419 		    val & BMCR_RESET)
420 			return phy_init_hw(phydev);
421 
422 		if (change_autoneg)
423 			return phy_start_aneg(phydev);
424 
425 		return 0;
426 
427 	case SIOCSHWTSTAMP:
428 		if (phydev->mii_ts && phydev->mii_ts->hwtstamp)
429 			return phydev->mii_ts->hwtstamp(phydev->mii_ts, ifr);
430 		/* fall through */
431 
432 	default:
433 		return -EOPNOTSUPP;
434 	}
435 }
436 EXPORT_SYMBOL(phy_mii_ioctl);
437 
438 /**
439  * phy_do_ioctl - generic ndo_do_ioctl implementation
440  * @dev: the net_device struct
441  * @ifr: &struct ifreq for socket ioctl's
442  * @cmd: ioctl cmd to execute
443  */
444 int phy_do_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
445 {
446 	if (!dev->phydev)
447 		return -ENODEV;
448 
449 	return phy_mii_ioctl(dev->phydev, ifr, cmd);
450 }
451 EXPORT_SYMBOL(phy_do_ioctl);
452 
453 /* same as phy_do_ioctl, but ensures that net_device is running */
454 int phy_do_ioctl_running(struct net_device *dev, struct ifreq *ifr, int cmd)
455 {
456 	if (!netif_running(dev))
457 		return -ENODEV;
458 
459 	return phy_do_ioctl(dev, ifr, cmd);
460 }
461 EXPORT_SYMBOL(phy_do_ioctl_running);
462 
463 void phy_queue_state_machine(struct phy_device *phydev, unsigned long jiffies)
464 {
465 	mod_delayed_work(system_power_efficient_wq, &phydev->state_queue,
466 			 jiffies);
467 }
468 EXPORT_SYMBOL(phy_queue_state_machine);
469 
470 static void phy_trigger_machine(struct phy_device *phydev)
471 {
472 	phy_queue_state_machine(phydev, 0);
473 }
474 
475 static int phy_config_aneg(struct phy_device *phydev)
476 {
477 	if (phydev->drv->config_aneg)
478 		return phydev->drv->config_aneg(phydev);
479 
480 	/* Clause 45 PHYs that don't implement Clause 22 registers are not
481 	 * allowed to call genphy_config_aneg()
482 	 */
483 	if (phydev->is_c45 && !(phydev->c45_ids.devices_in_package & BIT(0)))
484 		return genphy_c45_config_aneg(phydev);
485 
486 	return genphy_config_aneg(phydev);
487 }
488 
489 /**
490  * phy_check_link_status - check link status and set state accordingly
491  * @phydev: the phy_device struct
492  *
493  * Description: Check for link and whether autoneg was triggered / is running
494  * and set state accordingly
495  */
496 static int phy_check_link_status(struct phy_device *phydev)
497 {
498 	int err;
499 
500 	WARN_ON(!mutex_is_locked(&phydev->lock));
501 
502 	/* Keep previous state if loopback is enabled because some PHYs
503 	 * report that Link is Down when loopback is enabled.
504 	 */
505 	if (phydev->loopback_enabled)
506 		return 0;
507 
508 	err = phy_read_status(phydev);
509 	if (err)
510 		return err;
511 
512 	if (phydev->link && phydev->state != PHY_RUNNING) {
513 		phy_check_downshift(phydev);
514 		phydev->state = PHY_RUNNING;
515 		phy_link_up(phydev);
516 	} else if (!phydev->link && phydev->state != PHY_NOLINK) {
517 		phydev->state = PHY_NOLINK;
518 		phy_link_down(phydev, true);
519 	}
520 
521 	return 0;
522 }
523 
524 /**
525  * phy_start_aneg - start auto-negotiation for this PHY device
526  * @phydev: the phy_device struct
527  *
528  * Description: Sanitizes the settings (if we're not autonegotiating
529  *   them), and then calls the driver's config_aneg function.
530  *   If the PHYCONTROL Layer is operating, we change the state to
531  *   reflect the beginning of Auto-negotiation or forcing.
532  */
533 int phy_start_aneg(struct phy_device *phydev)
534 {
535 	int err;
536 
537 	if (!phydev->drv)
538 		return -EIO;
539 
540 	mutex_lock(&phydev->lock);
541 
542 	if (AUTONEG_DISABLE == phydev->autoneg)
543 		phy_sanitize_settings(phydev);
544 
545 	err = phy_config_aneg(phydev);
546 	if (err < 0)
547 		goto out_unlock;
548 
549 	if (phy_is_started(phydev))
550 		err = phy_check_link_status(phydev);
551 out_unlock:
552 	mutex_unlock(&phydev->lock);
553 
554 	return err;
555 }
556 EXPORT_SYMBOL(phy_start_aneg);
557 
558 static int phy_poll_aneg_done(struct phy_device *phydev)
559 {
560 	unsigned int retries = 100;
561 	int ret;
562 
563 	do {
564 		msleep(100);
565 		ret = phy_aneg_done(phydev);
566 	} while (!ret && --retries);
567 
568 	if (!ret)
569 		return -ETIMEDOUT;
570 
571 	return ret < 0 ? ret : 0;
572 }
573 
574 /**
575  * phy_speed_down - set speed to lowest speed supported by both link partners
576  * @phydev: the phy_device struct
577  * @sync: perform action synchronously
578  *
579  * Description: Typically used to save energy when waiting for a WoL packet
580  *
581  * WARNING: Setting sync to false may cause the system being unable to suspend
582  * in case the PHY generates an interrupt when finishing the autonegotiation.
583  * This interrupt may wake up the system immediately after suspend.
584  * Therefore use sync = false only if you're sure it's safe with the respective
585  * network chip.
586  */
587 int phy_speed_down(struct phy_device *phydev, bool sync)
588 {
589 	__ETHTOOL_DECLARE_LINK_MODE_MASK(adv_tmp);
590 	int ret;
591 
592 	if (phydev->autoneg != AUTONEG_ENABLE)
593 		return 0;
594 
595 	linkmode_copy(adv_tmp, phydev->advertising);
596 
597 	ret = phy_speed_down_core(phydev);
598 	if (ret)
599 		return ret;
600 
601 	linkmode_copy(phydev->adv_old, adv_tmp);
602 
603 	if (linkmode_equal(phydev->advertising, adv_tmp))
604 		return 0;
605 
606 	ret = phy_config_aneg(phydev);
607 	if (ret)
608 		return ret;
609 
610 	return sync ? phy_poll_aneg_done(phydev) : 0;
611 }
612 EXPORT_SYMBOL_GPL(phy_speed_down);
613 
614 /**
615  * phy_speed_up - (re)set advertised speeds to all supported speeds
616  * @phydev: the phy_device struct
617  *
618  * Description: Used to revert the effect of phy_speed_down
619  */
620 int phy_speed_up(struct phy_device *phydev)
621 {
622 	__ETHTOOL_DECLARE_LINK_MODE_MASK(adv_tmp);
623 
624 	if (phydev->autoneg != AUTONEG_ENABLE)
625 		return 0;
626 
627 	if (linkmode_empty(phydev->adv_old))
628 		return 0;
629 
630 	linkmode_copy(adv_tmp, phydev->advertising);
631 	linkmode_copy(phydev->advertising, phydev->adv_old);
632 	linkmode_zero(phydev->adv_old);
633 
634 	if (linkmode_equal(phydev->advertising, adv_tmp))
635 		return 0;
636 
637 	return phy_config_aneg(phydev);
638 }
639 EXPORT_SYMBOL_GPL(phy_speed_up);
640 
641 /**
642  * phy_start_machine - start PHY state machine tracking
643  * @phydev: the phy_device struct
644  *
645  * Description: The PHY infrastructure can run a state machine
646  *   which tracks whether the PHY is starting up, negotiating,
647  *   etc.  This function starts the delayed workqueue which tracks
648  *   the state of the PHY. If you want to maintain your own state machine,
649  *   do not call this function.
650  */
651 void phy_start_machine(struct phy_device *phydev)
652 {
653 	phy_trigger_machine(phydev);
654 }
655 EXPORT_SYMBOL_GPL(phy_start_machine);
656 
657 /**
658  * phy_stop_machine - stop the PHY state machine tracking
659  * @phydev: target phy_device struct
660  *
661  * Description: Stops the state machine delayed workqueue, sets the
662  *   state to UP (unless it wasn't up yet). This function must be
663  *   called BEFORE phy_detach.
664  */
665 void phy_stop_machine(struct phy_device *phydev)
666 {
667 	cancel_delayed_work_sync(&phydev->state_queue);
668 
669 	mutex_lock(&phydev->lock);
670 	if (phy_is_started(phydev))
671 		phydev->state = PHY_UP;
672 	mutex_unlock(&phydev->lock);
673 }
674 
675 /**
676  * phy_error - enter HALTED state for this PHY device
677  * @phydev: target phy_device struct
678  *
679  * Moves the PHY to the HALTED state in response to a read
680  * or write error, and tells the controller the link is down.
681  * Must not be called from interrupt context, or while the
682  * phydev->lock is held.
683  */
684 static void phy_error(struct phy_device *phydev)
685 {
686 	WARN_ON(1);
687 
688 	mutex_lock(&phydev->lock);
689 	phydev->state = PHY_HALTED;
690 	mutex_unlock(&phydev->lock);
691 
692 	phy_trigger_machine(phydev);
693 }
694 
695 /**
696  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
697  * @phydev: target phy_device struct
698  */
699 static int phy_disable_interrupts(struct phy_device *phydev)
700 {
701 	int err;
702 
703 	/* Disable PHY interrupts */
704 	err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
705 	if (err)
706 		return err;
707 
708 	/* Clear the interrupt */
709 	return phy_clear_interrupt(phydev);
710 }
711 
712 /**
713  * phy_interrupt - PHY interrupt handler
714  * @irq: interrupt line
715  * @phy_dat: phy_device pointer
716  *
717  * Description: Handle PHY interrupt
718  */
719 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
720 {
721 	struct phy_device *phydev = phy_dat;
722 	struct phy_driver *drv = phydev->drv;
723 
724 	if (drv->handle_interrupt)
725 		return drv->handle_interrupt(phydev);
726 
727 	if (drv->did_interrupt && !drv->did_interrupt(phydev))
728 		return IRQ_NONE;
729 
730 	/* reschedule state queue work to run as soon as possible */
731 	phy_trigger_machine(phydev);
732 
733 	/* did_interrupt() may have cleared the interrupt already */
734 	if (!drv->did_interrupt && phy_clear_interrupt(phydev)) {
735 		phy_error(phydev);
736 		return IRQ_NONE;
737 	}
738 
739 	return IRQ_HANDLED;
740 }
741 
742 /**
743  * phy_enable_interrupts - Enable the interrupts from the PHY side
744  * @phydev: target phy_device struct
745  */
746 static int phy_enable_interrupts(struct phy_device *phydev)
747 {
748 	int err = phy_clear_interrupt(phydev);
749 
750 	if (err < 0)
751 		return err;
752 
753 	return phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
754 }
755 
756 /**
757  * phy_request_interrupt - request and enable interrupt for a PHY device
758  * @phydev: target phy_device struct
759  *
760  * Description: Request and enable the interrupt for the given PHY.
761  *   If this fails, then we set irq to PHY_POLL.
762  *   This should only be called with a valid IRQ number.
763  */
764 void phy_request_interrupt(struct phy_device *phydev)
765 {
766 	int err;
767 
768 	err = request_threaded_irq(phydev->irq, NULL, phy_interrupt,
769 				   IRQF_ONESHOT | IRQF_SHARED,
770 				   phydev_name(phydev), phydev);
771 	if (err) {
772 		phydev_warn(phydev, "Error %d requesting IRQ %d, falling back to polling\n",
773 			    err, phydev->irq);
774 		phydev->irq = PHY_POLL;
775 	} else {
776 		if (phy_enable_interrupts(phydev)) {
777 			phydev_warn(phydev, "Can't enable interrupt, falling back to polling\n");
778 			phy_free_interrupt(phydev);
779 			phydev->irq = PHY_POLL;
780 		}
781 	}
782 }
783 EXPORT_SYMBOL(phy_request_interrupt);
784 
785 /**
786  * phy_free_interrupt - disable and free interrupt for a PHY device
787  * @phydev: target phy_device struct
788  *
789  * Description: Disable and free the interrupt for the given PHY.
790  *   This should only be called with a valid IRQ number.
791  */
792 void phy_free_interrupt(struct phy_device *phydev)
793 {
794 	phy_disable_interrupts(phydev);
795 	free_irq(phydev->irq, phydev);
796 }
797 EXPORT_SYMBOL(phy_free_interrupt);
798 
799 /**
800  * phy_stop - Bring down the PHY link, and stop checking the status
801  * @phydev: target phy_device struct
802  */
803 void phy_stop(struct phy_device *phydev)
804 {
805 	if (!phy_is_started(phydev)) {
806 		WARN(1, "called from state %s\n",
807 		     phy_state_to_str(phydev->state));
808 		return;
809 	}
810 
811 	mutex_lock(&phydev->lock);
812 
813 	if (phydev->sfp_bus)
814 		sfp_upstream_stop(phydev->sfp_bus);
815 
816 	phydev->state = PHY_HALTED;
817 
818 	mutex_unlock(&phydev->lock);
819 
820 	phy_state_machine(&phydev->state_queue.work);
821 	phy_stop_machine(phydev);
822 
823 	/* Cannot call flush_scheduled_work() here as desired because
824 	 * of rtnl_lock(), but PHY_HALTED shall guarantee irq handler
825 	 * will not reenable interrupts.
826 	 */
827 }
828 EXPORT_SYMBOL(phy_stop);
829 
830 /**
831  * phy_start - start or restart a PHY device
832  * @phydev: target phy_device struct
833  *
834  * Description: Indicates the attached device's readiness to
835  *   handle PHY-related work.  Used during startup to start the
836  *   PHY, and after a call to phy_stop() to resume operation.
837  *   Also used to indicate the MDIO bus has cleared an error
838  *   condition.
839  */
840 void phy_start(struct phy_device *phydev)
841 {
842 	mutex_lock(&phydev->lock);
843 
844 	if (phydev->state != PHY_READY && phydev->state != PHY_HALTED) {
845 		WARN(1, "called from state %s\n",
846 		     phy_state_to_str(phydev->state));
847 		goto out;
848 	}
849 
850 	if (phydev->sfp_bus)
851 		sfp_upstream_start(phydev->sfp_bus);
852 
853 	/* if phy was suspended, bring the physical link up again */
854 	__phy_resume(phydev);
855 
856 	phydev->state = PHY_UP;
857 
858 	phy_start_machine(phydev);
859 out:
860 	mutex_unlock(&phydev->lock);
861 }
862 EXPORT_SYMBOL(phy_start);
863 
864 /**
865  * phy_state_machine - Handle the state machine
866  * @work: work_struct that describes the work to be done
867  */
868 void phy_state_machine(struct work_struct *work)
869 {
870 	struct delayed_work *dwork = to_delayed_work(work);
871 	struct phy_device *phydev =
872 			container_of(dwork, struct phy_device, state_queue);
873 	bool needs_aneg = false, do_suspend = false;
874 	enum phy_state old_state;
875 	int err = 0;
876 
877 	mutex_lock(&phydev->lock);
878 
879 	old_state = phydev->state;
880 
881 	switch (phydev->state) {
882 	case PHY_DOWN:
883 	case PHY_READY:
884 		break;
885 	case PHY_UP:
886 		needs_aneg = true;
887 
888 		break;
889 	case PHY_NOLINK:
890 	case PHY_RUNNING:
891 		err = phy_check_link_status(phydev);
892 		break;
893 	case PHY_HALTED:
894 		if (phydev->link) {
895 			phydev->link = 0;
896 			phy_link_down(phydev, true);
897 		}
898 		do_suspend = true;
899 		break;
900 	}
901 
902 	mutex_unlock(&phydev->lock);
903 
904 	if (needs_aneg)
905 		err = phy_start_aneg(phydev);
906 	else if (do_suspend)
907 		phy_suspend(phydev);
908 
909 	if (err < 0)
910 		phy_error(phydev);
911 
912 	if (old_state != phydev->state) {
913 		phydev_dbg(phydev, "PHY state change %s -> %s\n",
914 			   phy_state_to_str(old_state),
915 			   phy_state_to_str(phydev->state));
916 		if (phydev->drv && phydev->drv->link_change_notify)
917 			phydev->drv->link_change_notify(phydev);
918 	}
919 
920 	/* Only re-schedule a PHY state machine change if we are polling the
921 	 * PHY, if PHY_IGNORE_INTERRUPT is set, then we will be moving
922 	 * between states from phy_mac_interrupt().
923 	 *
924 	 * In state PHY_HALTED the PHY gets suspended, so rescheduling the
925 	 * state machine would be pointless and possibly error prone when
926 	 * called from phy_disconnect() synchronously.
927 	 */
928 	mutex_lock(&phydev->lock);
929 	if (phy_polling_mode(phydev) && phy_is_started(phydev))
930 		phy_queue_state_machine(phydev, PHY_STATE_TIME);
931 	mutex_unlock(&phydev->lock);
932 }
933 
934 /**
935  * phy_mac_interrupt - MAC says the link has changed
936  * @phydev: phy_device struct with changed link
937  *
938  * The MAC layer is able to indicate there has been a change in the PHY link
939  * status. Trigger the state machine and work a work queue.
940  */
941 void phy_mac_interrupt(struct phy_device *phydev)
942 {
943 	/* Trigger a state machine change */
944 	phy_trigger_machine(phydev);
945 }
946 EXPORT_SYMBOL(phy_mac_interrupt);
947 
948 static void mmd_eee_adv_to_linkmode(unsigned long *advertising, u16 eee_adv)
949 {
950 	linkmode_zero(advertising);
951 
952 	if (eee_adv & MDIO_EEE_100TX)
953 		linkmode_set_bit(ETHTOOL_LINK_MODE_100baseT_Full_BIT,
954 				 advertising);
955 	if (eee_adv & MDIO_EEE_1000T)
956 		linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
957 				 advertising);
958 	if (eee_adv & MDIO_EEE_10GT)
959 		linkmode_set_bit(ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
960 				 advertising);
961 	if (eee_adv & MDIO_EEE_1000KX)
962 		linkmode_set_bit(ETHTOOL_LINK_MODE_1000baseKX_Full_BIT,
963 				 advertising);
964 	if (eee_adv & MDIO_EEE_10GKX4)
965 		linkmode_set_bit(ETHTOOL_LINK_MODE_10000baseKX4_Full_BIT,
966 				 advertising);
967 	if (eee_adv & MDIO_EEE_10GKR)
968 		linkmode_set_bit(ETHTOOL_LINK_MODE_10000baseKR_Full_BIT,
969 				 advertising);
970 }
971 
972 /**
973  * phy_init_eee - init and check the EEE feature
974  * @phydev: target phy_device struct
975  * @clk_stop_enable: PHY may stop the clock during LPI
976  *
977  * Description: it checks if the Energy-Efficient Ethernet (EEE)
978  * is supported by looking at the MMD registers 3.20 and 7.60/61
979  * and it programs the MMD register 3.0 setting the "Clock stop enable"
980  * bit if required.
981  */
982 int phy_init_eee(struct phy_device *phydev, bool clk_stop_enable)
983 {
984 	if (!phydev->drv)
985 		return -EIO;
986 
987 	/* According to 802.3az,the EEE is supported only in full duplex-mode.
988 	 */
989 	if (phydev->duplex == DUPLEX_FULL) {
990 		__ETHTOOL_DECLARE_LINK_MODE_MASK(common);
991 		__ETHTOOL_DECLARE_LINK_MODE_MASK(lp);
992 		__ETHTOOL_DECLARE_LINK_MODE_MASK(adv);
993 		int eee_lp, eee_cap, eee_adv;
994 		int status;
995 		u32 cap;
996 
997 		/* Read phy status to properly get the right settings */
998 		status = phy_read_status(phydev);
999 		if (status)
1000 			return status;
1001 
1002 		/* First check if the EEE ability is supported */
1003 		eee_cap = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_EEE_ABLE);
1004 		if (eee_cap <= 0)
1005 			goto eee_exit_err;
1006 
1007 		cap = mmd_eee_cap_to_ethtool_sup_t(eee_cap);
1008 		if (!cap)
1009 			goto eee_exit_err;
1010 
1011 		/* Check which link settings negotiated and verify it in
1012 		 * the EEE advertising registers.
1013 		 */
1014 		eee_lp = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_LPABLE);
1015 		if (eee_lp <= 0)
1016 			goto eee_exit_err;
1017 
1018 		eee_adv = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_ADV);
1019 		if (eee_adv <= 0)
1020 			goto eee_exit_err;
1021 
1022 		mmd_eee_adv_to_linkmode(adv, eee_adv);
1023 		mmd_eee_adv_to_linkmode(lp, eee_lp);
1024 		linkmode_and(common, adv, lp);
1025 
1026 		if (!phy_check_valid(phydev->speed, phydev->duplex, common))
1027 			goto eee_exit_err;
1028 
1029 		if (clk_stop_enable)
1030 			/* Configure the PHY to stop receiving xMII
1031 			 * clock while it is signaling LPI.
1032 			 */
1033 			phy_set_bits_mmd(phydev, MDIO_MMD_PCS, MDIO_CTRL1,
1034 					 MDIO_PCS_CTRL1_CLKSTOP_EN);
1035 
1036 		return 0; /* EEE supported */
1037 	}
1038 eee_exit_err:
1039 	return -EPROTONOSUPPORT;
1040 }
1041 EXPORT_SYMBOL(phy_init_eee);
1042 
1043 /**
1044  * phy_get_eee_err - report the EEE wake error count
1045  * @phydev: target phy_device struct
1046  *
1047  * Description: it is to report the number of time where the PHY
1048  * failed to complete its normal wake sequence.
1049  */
1050 int phy_get_eee_err(struct phy_device *phydev)
1051 {
1052 	if (!phydev->drv)
1053 		return -EIO;
1054 
1055 	return phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_EEE_WK_ERR);
1056 }
1057 EXPORT_SYMBOL(phy_get_eee_err);
1058 
1059 /**
1060  * phy_ethtool_get_eee - get EEE supported and status
1061  * @phydev: target phy_device struct
1062  * @data: ethtool_eee data
1063  *
1064  * Description: it reportes the Supported/Advertisement/LP Advertisement
1065  * capabilities.
1066  */
1067 int phy_ethtool_get_eee(struct phy_device *phydev, struct ethtool_eee *data)
1068 {
1069 	int val;
1070 
1071 	if (!phydev->drv)
1072 		return -EIO;
1073 
1074 	/* Get Supported EEE */
1075 	val = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_EEE_ABLE);
1076 	if (val < 0)
1077 		return val;
1078 	data->supported = mmd_eee_cap_to_ethtool_sup_t(val);
1079 
1080 	/* Get advertisement EEE */
1081 	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_ADV);
1082 	if (val < 0)
1083 		return val;
1084 	data->advertised = mmd_eee_adv_to_ethtool_adv_t(val);
1085 	data->eee_enabled = !!data->advertised;
1086 
1087 	/* Get LP advertisement EEE */
1088 	val = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_LPABLE);
1089 	if (val < 0)
1090 		return val;
1091 	data->lp_advertised = mmd_eee_adv_to_ethtool_adv_t(val);
1092 
1093 	data->eee_active = !!(data->advertised & data->lp_advertised);
1094 
1095 	return 0;
1096 }
1097 EXPORT_SYMBOL(phy_ethtool_get_eee);
1098 
1099 /**
1100  * phy_ethtool_set_eee - set EEE supported and status
1101  * @phydev: target phy_device struct
1102  * @data: ethtool_eee data
1103  *
1104  * Description: it is to program the Advertisement EEE register.
1105  */
1106 int phy_ethtool_set_eee(struct phy_device *phydev, struct ethtool_eee *data)
1107 {
1108 	int cap, old_adv, adv = 0, ret;
1109 
1110 	if (!phydev->drv)
1111 		return -EIO;
1112 
1113 	/* Get Supported EEE */
1114 	cap = phy_read_mmd(phydev, MDIO_MMD_PCS, MDIO_PCS_EEE_ABLE);
1115 	if (cap < 0)
1116 		return cap;
1117 
1118 	old_adv = phy_read_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_ADV);
1119 	if (old_adv < 0)
1120 		return old_adv;
1121 
1122 	if (data->eee_enabled) {
1123 		adv = !data->advertised ? cap :
1124 		      ethtool_adv_to_mmd_eee_adv_t(data->advertised) & cap;
1125 		/* Mask prohibited EEE modes */
1126 		adv &= ~phydev->eee_broken_modes;
1127 	}
1128 
1129 	if (old_adv != adv) {
1130 		ret = phy_write_mmd(phydev, MDIO_MMD_AN, MDIO_AN_EEE_ADV, adv);
1131 		if (ret < 0)
1132 			return ret;
1133 
1134 		/* Restart autonegotiation so the new modes get sent to the
1135 		 * link partner.
1136 		 */
1137 		ret = phy_restart_aneg(phydev);
1138 		if (ret < 0)
1139 			return ret;
1140 	}
1141 
1142 	return 0;
1143 }
1144 EXPORT_SYMBOL(phy_ethtool_set_eee);
1145 
1146 int phy_ethtool_set_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
1147 {
1148 	if (phydev->drv && phydev->drv->set_wol)
1149 		return phydev->drv->set_wol(phydev, wol);
1150 
1151 	return -EOPNOTSUPP;
1152 }
1153 EXPORT_SYMBOL(phy_ethtool_set_wol);
1154 
1155 void phy_ethtool_get_wol(struct phy_device *phydev, struct ethtool_wolinfo *wol)
1156 {
1157 	if (phydev->drv && phydev->drv->get_wol)
1158 		phydev->drv->get_wol(phydev, wol);
1159 }
1160 EXPORT_SYMBOL(phy_ethtool_get_wol);
1161 
1162 int phy_ethtool_get_link_ksettings(struct net_device *ndev,
1163 				   struct ethtool_link_ksettings *cmd)
1164 {
1165 	struct phy_device *phydev = ndev->phydev;
1166 
1167 	if (!phydev)
1168 		return -ENODEV;
1169 
1170 	phy_ethtool_ksettings_get(phydev, cmd);
1171 
1172 	return 0;
1173 }
1174 EXPORT_SYMBOL(phy_ethtool_get_link_ksettings);
1175 
1176 int phy_ethtool_set_link_ksettings(struct net_device *ndev,
1177 				   const struct ethtool_link_ksettings *cmd)
1178 {
1179 	struct phy_device *phydev = ndev->phydev;
1180 
1181 	if (!phydev)
1182 		return -ENODEV;
1183 
1184 	return phy_ethtool_ksettings_set(phydev, cmd);
1185 }
1186 EXPORT_SYMBOL(phy_ethtool_set_link_ksettings);
1187 
1188 int phy_ethtool_nway_reset(struct net_device *ndev)
1189 {
1190 	struct phy_device *phydev = ndev->phydev;
1191 
1192 	if (!phydev)
1193 		return -ENODEV;
1194 
1195 	if (!phydev->drv)
1196 		return -EIO;
1197 
1198 	return phy_restart_aneg(phydev);
1199 }
1200 EXPORT_SYMBOL(phy_ethtool_nway_reset);
1201