xref: /linux/drivers/net/phy/phy_device.c (revision 858259cf7d1c443c836a2022b78cb281f0a9b95e)
1 /*
2  * drivers/net/phy/phy_device.c
3  *
4  * Framework for finding and configuring PHYs.
5  * Also contains generic PHY driver
6  *
7  * Author: Andy Fleming
8  *
9  * Copyright (c) 2004 Freescale Semiconductor, Inc.
10  *
11  * This program is free software; you can redistribute  it and/or modify it
12  * under  the terms of  the GNU General  Public License as published by the
13  * Free Software Foundation;  either version 2 of the  License, or (at your
14  * option) any later version.
15  *
16  */
17 #include <linux/config.h>
18 #include <linux/kernel.h>
19 #include <linux/sched.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/unistd.h>
23 #include <linux/slab.h>
24 #include <linux/interrupt.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/netdevice.h>
28 #include <linux/etherdevice.h>
29 #include <linux/skbuff.h>
30 #include <linux/spinlock.h>
31 #include <linux/mm.h>
32 #include <linux/module.h>
33 #include <linux/version.h>
34 #include <linux/mii.h>
35 #include <linux/ethtool.h>
36 #include <linux/phy.h>
37 
38 #include <asm/io.h>
39 #include <asm/irq.h>
40 #include <asm/uaccess.h>
41 
42 static struct phy_driver genphy_driver;
43 extern int mdio_bus_init(void);
44 extern void mdio_bus_exit(void);
45 
46 /* get_phy_device
47  *
48  * description: Reads the ID registers of the PHY at addr on the
49  *   bus, then allocates and returns the phy_device to
50  *   represent it.
51  */
52 struct phy_device * get_phy_device(struct mii_bus *bus, int addr)
53 {
54 	int phy_reg;
55 	u32 phy_id;
56 	struct phy_device *dev = NULL;
57 
58 	/* Grab the bits from PHYIR1, and put them
59 	 * in the upper half */
60 	phy_reg = bus->read(bus, addr, MII_PHYSID1);
61 
62 	if (phy_reg < 0)
63 		return ERR_PTR(phy_reg);
64 
65 	phy_id = (phy_reg & 0xffff) << 16;
66 
67 	/* Grab the bits from PHYIR2, and put them in the lower half */
68 	phy_reg = bus->read(bus, addr, MII_PHYSID2);
69 
70 	if (phy_reg < 0)
71 		return ERR_PTR(phy_reg);
72 
73 	phy_id |= (phy_reg & 0xffff);
74 
75 	/* If the phy_id is all Fs, there is no device there */
76 	if (0xffffffff == phy_id)
77 		return NULL;
78 
79 	/* Otherwise, we allocate the device, and initialize the
80 	 * default values */
81 	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
82 
83 	if (NULL == dev)
84 		return ERR_PTR(-ENOMEM);
85 
86 	dev->speed = 0;
87 	dev->duplex = -1;
88 	dev->pause = dev->asym_pause = 0;
89 	dev->link = 1;
90 
91 	dev->autoneg = AUTONEG_ENABLE;
92 
93 	dev->addr = addr;
94 	dev->phy_id = phy_id;
95 	dev->bus = bus;
96 
97 	dev->state = PHY_DOWN;
98 
99 	spin_lock_init(&dev->lock);
100 
101 	return dev;
102 }
103 
104 /* phy_prepare_link:
105  *
106  * description: Tells the PHY infrastructure to handle the
107  *   gory details on monitoring link status (whether through
108  *   polling or an interrupt), and to call back to the
109  *   connected device driver when the link status changes.
110  *   If you want to monitor your own link state, don't call
111  *   this function */
112 void phy_prepare_link(struct phy_device *phydev,
113 		void (*handler)(struct net_device *))
114 {
115 	phydev->adjust_link = handler;
116 }
117 
118 /* phy_connect:
119  *
120  * description: Convenience function for connecting ethernet
121  *   devices to PHY devices.  The default behavior is for
122  *   the PHY infrastructure to handle everything, and only notify
123  *   the connected driver when the link status changes.  If you
124  *   don't want, or can't use the provided functionality, you may
125  *   choose to call only the subset of functions which provide
126  *   the desired functionality.
127  */
128 struct phy_device * phy_connect(struct net_device *dev, const char *phy_id,
129 		void (*handler)(struct net_device *), u32 flags)
130 {
131 	struct phy_device *phydev;
132 
133 	phydev = phy_attach(dev, phy_id, flags);
134 
135 	if (IS_ERR(phydev))
136 		return phydev;
137 
138 	phy_prepare_link(phydev, handler);
139 
140 	phy_start_machine(phydev, NULL);
141 
142 	if (phydev->irq > 0)
143 		phy_start_interrupts(phydev);
144 
145 	return phydev;
146 }
147 EXPORT_SYMBOL(phy_connect);
148 
149 void phy_disconnect(struct phy_device *phydev)
150 {
151 	if (phydev->irq > 0)
152 		phy_stop_interrupts(phydev);
153 
154 	phy_stop_machine(phydev);
155 
156 	phydev->adjust_link = NULL;
157 
158 	phy_detach(phydev);
159 }
160 EXPORT_SYMBOL(phy_disconnect);
161 
162 /* phy_attach:
163  *
164  *   description: Called by drivers to attach to a particular PHY
165  *     device. The phy_device is found, and properly hooked up
166  *     to the phy_driver.  If no driver is attached, then the
167  *     genphy_driver is used.  The phy_device is given a ptr to
168  *     the attaching device, and given a callback for link status
169  *     change.  The phy_device is returned to the attaching
170  *     driver.
171  */
172 static int phy_compare_id(struct device *dev, void *data)
173 {
174 	return strcmp((char *)data, dev->bus_id) ? 0 : 1;
175 }
176 
177 struct phy_device *phy_attach(struct net_device *dev,
178 		const char *phy_id, u32 flags)
179 {
180 	struct bus_type *bus = &mdio_bus_type;
181 	struct phy_device *phydev;
182 	struct device *d;
183 
184 	/* Search the list of PHY devices on the mdio bus for the
185 	 * PHY with the requested name */
186 	d = bus_find_device(bus, NULL, (void *)phy_id, phy_compare_id);
187 
188 	if (d) {
189 		phydev = to_phy_device(d);
190 	} else {
191 		printk(KERN_ERR "%s not found\n", phy_id);
192 		return ERR_PTR(-ENODEV);
193 	}
194 
195 	/* Assume that if there is no driver, that it doesn't
196 	 * exist, and we should use the genphy driver. */
197 	if (NULL == d->driver) {
198 		int err;
199 		down_write(&d->bus->subsys.rwsem);
200 		d->driver = &genphy_driver.driver;
201 
202 		err = d->driver->probe(d);
203 
204 		if (err < 0)
205 			return ERR_PTR(err);
206 
207 		device_bind_driver(d);
208 		up_write(&d->bus->subsys.rwsem);
209 	}
210 
211 	if (phydev->attached_dev) {
212 		printk(KERN_ERR "%s: %s already attached\n",
213 				dev->name, phy_id);
214 		return ERR_PTR(-EBUSY);
215 	}
216 
217 	phydev->attached_dev = dev;
218 
219 	phydev->dev_flags = flags;
220 
221 	return phydev;
222 }
223 EXPORT_SYMBOL(phy_attach);
224 
225 void phy_detach(struct phy_device *phydev)
226 {
227 	phydev->attached_dev = NULL;
228 
229 	/* If the device had no specific driver before (i.e. - it
230 	 * was using the generic driver), we unbind the device
231 	 * from the generic driver so that there's a chance a
232 	 * real driver could be loaded */
233 	if (phydev->dev.driver == &genphy_driver.driver) {
234 		down_write(&phydev->dev.bus->subsys.rwsem);
235 		device_release_driver(&phydev->dev);
236 		up_write(&phydev->dev.bus->subsys.rwsem);
237 	}
238 }
239 EXPORT_SYMBOL(phy_detach);
240 
241 
242 /* Generic PHY support and helper functions */
243 
244 /* genphy_config_advert
245  *
246  * description: Writes MII_ADVERTISE with the appropriate values,
247  *   after sanitizing the values to make sure we only advertise
248  *   what is supported
249  */
250 int genphy_config_advert(struct phy_device *phydev)
251 {
252 	u32 advertise;
253 	int adv;
254 	int err;
255 
256 	/* Only allow advertising what
257 	 * this PHY supports */
258 	phydev->advertising &= phydev->supported;
259 	advertise = phydev->advertising;
260 
261 	/* Setup standard advertisement */
262 	adv = phy_read(phydev, MII_ADVERTISE);
263 
264 	if (adv < 0)
265 		return adv;
266 
267 	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
268 		 ADVERTISE_PAUSE_ASYM);
269 	if (advertise & ADVERTISED_10baseT_Half)
270 		adv |= ADVERTISE_10HALF;
271 	if (advertise & ADVERTISED_10baseT_Full)
272 		adv |= ADVERTISE_10FULL;
273 	if (advertise & ADVERTISED_100baseT_Half)
274 		adv |= ADVERTISE_100HALF;
275 	if (advertise & ADVERTISED_100baseT_Full)
276 		adv |= ADVERTISE_100FULL;
277 	if (advertise & ADVERTISED_Pause)
278 		adv |= ADVERTISE_PAUSE_CAP;
279 	if (advertise & ADVERTISED_Asym_Pause)
280 		adv |= ADVERTISE_PAUSE_ASYM;
281 
282 	err = phy_write(phydev, MII_ADVERTISE, adv);
283 
284 	if (err < 0)
285 		return err;
286 
287 	/* Configure gigabit if it's supported */
288 	if (phydev->supported & (SUPPORTED_1000baseT_Half |
289 				SUPPORTED_1000baseT_Full)) {
290 		adv = phy_read(phydev, MII_CTRL1000);
291 
292 		if (adv < 0)
293 			return adv;
294 
295 		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
296 		if (advertise & SUPPORTED_1000baseT_Half)
297 			adv |= ADVERTISE_1000HALF;
298 		if (advertise & SUPPORTED_1000baseT_Full)
299 			adv |= ADVERTISE_1000FULL;
300 		err = phy_write(phydev, MII_CTRL1000, adv);
301 
302 		if (err < 0)
303 			return err;
304 	}
305 
306 	return adv;
307 }
308 EXPORT_SYMBOL(genphy_config_advert);
309 
310 /* genphy_setup_forced
311  *
312  * description: Configures MII_BMCR to force speed/duplex
313  *   to the values in phydev. Assumes that the values are valid.
314  *   Please see phy_sanitize_settings() */
315 int genphy_setup_forced(struct phy_device *phydev)
316 {
317 	int ctl = BMCR_RESET;
318 
319 	phydev->pause = phydev->asym_pause = 0;
320 
321 	if (SPEED_1000 == phydev->speed)
322 		ctl |= BMCR_SPEED1000;
323 	else if (SPEED_100 == phydev->speed)
324 		ctl |= BMCR_SPEED100;
325 
326 	if (DUPLEX_FULL == phydev->duplex)
327 		ctl |= BMCR_FULLDPLX;
328 
329 	ctl = phy_write(phydev, MII_BMCR, ctl);
330 
331 	if (ctl < 0)
332 		return ctl;
333 
334 	/* We just reset the device, so we'd better configure any
335 	 * settings the PHY requires to operate */
336 	if (phydev->drv->config_init)
337 		ctl = phydev->drv->config_init(phydev);
338 
339 	return ctl;
340 }
341 
342 
343 /* Enable and Restart Autonegotiation */
344 int genphy_restart_aneg(struct phy_device *phydev)
345 {
346 	int ctl;
347 
348 	ctl = phy_read(phydev, MII_BMCR);
349 
350 	if (ctl < 0)
351 		return ctl;
352 
353 	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
354 
355 	/* Don't isolate the PHY if we're negotiating */
356 	ctl &= ~(BMCR_ISOLATE);
357 
358 	ctl = phy_write(phydev, MII_BMCR, ctl);
359 
360 	return ctl;
361 }
362 
363 
364 /* genphy_config_aneg
365  *
366  * description: If auto-negotiation is enabled, we configure the
367  *   advertising, and then restart auto-negotiation.  If it is not
368  *   enabled, then we write the BMCR
369  */
370 int genphy_config_aneg(struct phy_device *phydev)
371 {
372 	int err = 0;
373 
374 	if (AUTONEG_ENABLE == phydev->autoneg) {
375 		err = genphy_config_advert(phydev);
376 
377 		if (err < 0)
378 			return err;
379 
380 		err = genphy_restart_aneg(phydev);
381 	} else
382 		err = genphy_setup_forced(phydev);
383 
384 	return err;
385 }
386 EXPORT_SYMBOL(genphy_config_aneg);
387 
388 /* genphy_update_link
389  *
390  * description: Update the value in phydev->link to reflect the
391  *   current link value.  In order to do this, we need to read
392  *   the status register twice, keeping the second value
393  */
394 int genphy_update_link(struct phy_device *phydev)
395 {
396 	int status;
397 
398 	/* Do a fake read */
399 	status = phy_read(phydev, MII_BMSR);
400 
401 	if (status < 0)
402 		return status;
403 
404 	/* Read link and autonegotiation status */
405 	status = phy_read(phydev, MII_BMSR);
406 
407 	if (status < 0)
408 		return status;
409 
410 	if ((status & BMSR_LSTATUS) == 0)
411 		phydev->link = 0;
412 	else
413 		phydev->link = 1;
414 
415 	return 0;
416 }
417 
418 /* genphy_read_status
419  *
420  * description: Check the link, then figure out the current state
421  *   by comparing what we advertise with what the link partner
422  *   advertises.  Start by checking the gigabit possibilities,
423  *   then move on to 10/100.
424  */
425 int genphy_read_status(struct phy_device *phydev)
426 {
427 	int adv;
428 	int err;
429 	int lpa;
430 	int lpagb = 0;
431 
432 	/* Update the link, but return if there
433 	 * was an error */
434 	err = genphy_update_link(phydev);
435 	if (err)
436 		return err;
437 
438 	if (AUTONEG_ENABLE == phydev->autoneg) {
439 		if (phydev->supported & (SUPPORTED_1000baseT_Half
440 					| SUPPORTED_1000baseT_Full)) {
441 			lpagb = phy_read(phydev, MII_STAT1000);
442 
443 			if (lpagb < 0)
444 				return lpagb;
445 
446 			adv = phy_read(phydev, MII_CTRL1000);
447 
448 			if (adv < 0)
449 				return adv;
450 
451 			lpagb &= adv << 2;
452 		}
453 
454 		lpa = phy_read(phydev, MII_LPA);
455 
456 		if (lpa < 0)
457 			return lpa;
458 
459 		adv = phy_read(phydev, MII_ADVERTISE);
460 
461 		if (adv < 0)
462 			return adv;
463 
464 		lpa &= adv;
465 
466 		phydev->speed = SPEED_10;
467 		phydev->duplex = DUPLEX_HALF;
468 		phydev->pause = phydev->asym_pause = 0;
469 
470 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
471 			phydev->speed = SPEED_1000;
472 
473 			if (lpagb & LPA_1000FULL)
474 				phydev->duplex = DUPLEX_FULL;
475 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
476 			phydev->speed = SPEED_100;
477 
478 			if (lpa & LPA_100FULL)
479 				phydev->duplex = DUPLEX_FULL;
480 		} else
481 			if (lpa & LPA_10FULL)
482 				phydev->duplex = DUPLEX_FULL;
483 
484 		if (phydev->duplex == DUPLEX_FULL){
485 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
486 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
487 		}
488 	} else {
489 		int bmcr = phy_read(phydev, MII_BMCR);
490 		if (bmcr < 0)
491 			return bmcr;
492 
493 		if (bmcr & BMCR_FULLDPLX)
494 			phydev->duplex = DUPLEX_FULL;
495 		else
496 			phydev->duplex = DUPLEX_HALF;
497 
498 		if (bmcr & BMCR_SPEED1000)
499 			phydev->speed = SPEED_1000;
500 		else if (bmcr & BMCR_SPEED100)
501 			phydev->speed = SPEED_100;
502 		else
503 			phydev->speed = SPEED_10;
504 
505 		phydev->pause = phydev->asym_pause = 0;
506 	}
507 
508 	return 0;
509 }
510 EXPORT_SYMBOL(genphy_read_status);
511 
512 static int genphy_config_init(struct phy_device *phydev)
513 {
514 	u32 val;
515 	u32 features;
516 
517 	/* For now, I'll claim that the generic driver supports
518 	 * all possible port types */
519 	features = (SUPPORTED_TP | SUPPORTED_MII
520 			| SUPPORTED_AUI | SUPPORTED_FIBRE |
521 			SUPPORTED_BNC);
522 
523 	/* Do we support autonegotiation? */
524 	val = phy_read(phydev, MII_BMSR);
525 
526 	if (val < 0)
527 		return val;
528 
529 	if (val & BMSR_ANEGCAPABLE)
530 		features |= SUPPORTED_Autoneg;
531 
532 	if (val & BMSR_100FULL)
533 		features |= SUPPORTED_100baseT_Full;
534 	if (val & BMSR_100HALF)
535 		features |= SUPPORTED_100baseT_Half;
536 	if (val & BMSR_10FULL)
537 		features |= SUPPORTED_10baseT_Full;
538 	if (val & BMSR_10HALF)
539 		features |= SUPPORTED_10baseT_Half;
540 
541 	if (val & BMSR_ESTATEN) {
542 		val = phy_read(phydev, MII_ESTATUS);
543 
544 		if (val < 0)
545 			return val;
546 
547 		if (val & ESTATUS_1000_TFULL)
548 			features |= SUPPORTED_1000baseT_Full;
549 		if (val & ESTATUS_1000_THALF)
550 			features |= SUPPORTED_1000baseT_Half;
551 	}
552 
553 	phydev->supported = features;
554 	phydev->advertising = features;
555 
556 	return 0;
557 }
558 
559 
560 /* phy_probe
561  *
562  * description: Take care of setting up the phy_device structure,
563  *   set the state to READY (the driver's init function should
564  *   set it to STARTING if needed).
565  */
566 static int phy_probe(struct device *dev)
567 {
568 	struct phy_device *phydev;
569 	struct phy_driver *phydrv;
570 	struct device_driver *drv;
571 	int err = 0;
572 
573 	phydev = to_phy_device(dev);
574 
575 	/* Make sure the driver is held.
576 	 * XXX -- Is this correct? */
577 	drv = get_driver(phydev->dev.driver);
578 	phydrv = to_phy_driver(drv);
579 	phydev->drv = phydrv;
580 
581 	/* Disable the interrupt if the PHY doesn't support it */
582 	if (!(phydrv->flags & PHY_HAS_INTERRUPT))
583 		phydev->irq = PHY_POLL;
584 
585 	spin_lock(&phydev->lock);
586 
587 	/* Start out supporting everything. Eventually,
588 	 * a controller will attach, and may modify one
589 	 * or both of these values */
590 	phydev->supported = phydrv->features;
591 	phydev->advertising = phydrv->features;
592 
593 	/* Set the state to READY by default */
594 	phydev->state = PHY_READY;
595 
596 	if (phydev->drv->probe)
597 		err = phydev->drv->probe(phydev);
598 
599 	spin_unlock(&phydev->lock);
600 
601 	if (err < 0)
602 		return err;
603 
604 	if (phydev->drv->config_init)
605 		err = phydev->drv->config_init(phydev);
606 
607 	return err;
608 }
609 
610 static int phy_remove(struct device *dev)
611 {
612 	struct phy_device *phydev;
613 
614 	phydev = to_phy_device(dev);
615 
616 	spin_lock(&phydev->lock);
617 	phydev->state = PHY_DOWN;
618 	spin_unlock(&phydev->lock);
619 
620 	if (phydev->drv->remove)
621 		phydev->drv->remove(phydev);
622 
623 	put_driver(dev->driver);
624 	phydev->drv = NULL;
625 
626 	return 0;
627 }
628 
629 int phy_driver_register(struct phy_driver *new_driver)
630 {
631 	int retval;
632 
633 	memset(&new_driver->driver, 0, sizeof(new_driver->driver));
634 	new_driver->driver.name = new_driver->name;
635 	new_driver->driver.bus = &mdio_bus_type;
636 	new_driver->driver.probe = phy_probe;
637 	new_driver->driver.remove = phy_remove;
638 
639 	retval = driver_register(&new_driver->driver);
640 
641 	if (retval) {
642 		printk(KERN_ERR "%s: Error %d in registering driver\n",
643 				new_driver->name, retval);
644 
645 		return retval;
646 	}
647 
648 	pr_info("%s: Registered new driver\n", new_driver->name);
649 
650 	return 0;
651 }
652 EXPORT_SYMBOL(phy_driver_register);
653 
654 void phy_driver_unregister(struct phy_driver *drv)
655 {
656 	driver_unregister(&drv->driver);
657 }
658 EXPORT_SYMBOL(phy_driver_unregister);
659 
660 static struct phy_driver genphy_driver = {
661 	.phy_id		= 0xffffffff,
662 	.phy_id_mask	= 0xffffffff,
663 	.name		= "Generic PHY",
664 	.config_init	= genphy_config_init,
665 	.features	= 0,
666 	.config_aneg	= genphy_config_aneg,
667 	.read_status	= genphy_read_status,
668 	.driver		= {.owner= THIS_MODULE, },
669 };
670 
671 static int __init phy_init(void)
672 {
673 	int rc;
674 
675 	rc = mdio_bus_init();
676 	if (rc)
677 		return rc;
678 
679 	rc = phy_driver_register(&genphy_driver);
680 	if (rc)
681 		mdio_bus_exit();
682 
683 	return rc;
684 }
685 
686 static void __exit phy_exit(void)
687 {
688 	phy_driver_unregister(&genphy_driver);
689 	mdio_bus_exit();
690 }
691 
692 subsys_initcall(phy_init);
693 module_exit(phy_exit);
694