xref: /linux/drivers/net/phy/phy_device.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
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/mii.h>
34 #include <linux/ethtool.h>
35 #include <linux/phy.h>
36 
37 #include <asm/io.h>
38 #include <asm/irq.h>
39 #include <asm/uaccess.h>
40 
41 static struct phy_driver genphy_driver;
42 extern int mdio_bus_init(void);
43 extern void mdio_bus_exit(void);
44 
45 /* get_phy_device
46  *
47  * description: Reads the ID registers of the PHY at addr on the
48  *   bus, then allocates and returns the phy_device to
49  *   represent it.
50  */
51 struct phy_device * get_phy_device(struct mii_bus *bus, int addr)
52 {
53 	int phy_reg;
54 	u32 phy_id;
55 	struct phy_device *dev = NULL;
56 
57 	/* Grab the bits from PHYIR1, and put them
58 	 * in the upper half */
59 	phy_reg = bus->read(bus, addr, MII_PHYSID1);
60 
61 	if (phy_reg < 0)
62 		return ERR_PTR(phy_reg);
63 
64 	phy_id = (phy_reg & 0xffff) << 16;
65 
66 	/* Grab the bits from PHYIR2, and put them in the lower half */
67 	phy_reg = bus->read(bus, addr, MII_PHYSID2);
68 
69 	if (phy_reg < 0)
70 		return ERR_PTR(phy_reg);
71 
72 	phy_id |= (phy_reg & 0xffff);
73 
74 	/* If the phy_id is all Fs, there is no device there */
75 	if (0xffffffff == phy_id)
76 		return NULL;
77 
78 	/* Otherwise, we allocate the device, and initialize the
79 	 * default values */
80 	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
81 
82 	if (NULL == dev)
83 		return ERR_PTR(-ENOMEM);
84 
85 	dev->speed = 0;
86 	dev->duplex = -1;
87 	dev->pause = dev->asym_pause = 0;
88 	dev->link = 1;
89 
90 	dev->autoneg = AUTONEG_ENABLE;
91 
92 	dev->addr = addr;
93 	dev->phy_id = phy_id;
94 	dev->bus = bus;
95 
96 	dev->state = PHY_DOWN;
97 
98 	spin_lock_init(&dev->lock);
99 
100 	return dev;
101 }
102 
103 /* phy_prepare_link:
104  *
105  * description: Tells the PHY infrastructure to handle the
106  *   gory details on monitoring link status (whether through
107  *   polling or an interrupt), and to call back to the
108  *   connected device driver when the link status changes.
109  *   If you want to monitor your own link state, don't call
110  *   this function */
111 void phy_prepare_link(struct phy_device *phydev,
112 		void (*handler)(struct net_device *))
113 {
114 	phydev->adjust_link = handler;
115 }
116 
117 /* phy_connect:
118  *
119  * description: Convenience function for connecting ethernet
120  *   devices to PHY devices.  The default behavior is for
121  *   the PHY infrastructure to handle everything, and only notify
122  *   the connected driver when the link status changes.  If you
123  *   don't want, or can't use the provided functionality, you may
124  *   choose to call only the subset of functions which provide
125  *   the desired functionality.
126  */
127 struct phy_device * phy_connect(struct net_device *dev, const char *phy_id,
128 		void (*handler)(struct net_device *), u32 flags)
129 {
130 	struct phy_device *phydev;
131 
132 	phydev = phy_attach(dev, phy_id, flags);
133 
134 	if (IS_ERR(phydev))
135 		return phydev;
136 
137 	phy_prepare_link(phydev, handler);
138 
139 	phy_start_machine(phydev, NULL);
140 
141 	if (phydev->irq > 0)
142 		phy_start_interrupts(phydev);
143 
144 	return phydev;
145 }
146 EXPORT_SYMBOL(phy_connect);
147 
148 void phy_disconnect(struct phy_device *phydev)
149 {
150 	if (phydev->irq > 0)
151 		phy_stop_interrupts(phydev);
152 
153 	phy_stop_machine(phydev);
154 
155 	phydev->adjust_link = NULL;
156 
157 	phy_detach(phydev);
158 }
159 EXPORT_SYMBOL(phy_disconnect);
160 
161 /* phy_attach:
162  *
163  *   description: Called by drivers to attach to a particular PHY
164  *     device. The phy_device is found, and properly hooked up
165  *     to the phy_driver.  If no driver is attached, then the
166  *     genphy_driver is used.  The phy_device is given a ptr to
167  *     the attaching device, and given a callback for link status
168  *     change.  The phy_device is returned to the attaching
169  *     driver.
170  */
171 static int phy_compare_id(struct device *dev, void *data)
172 {
173 	return strcmp((char *)data, dev->bus_id) ? 0 : 1;
174 }
175 
176 struct phy_device *phy_attach(struct net_device *dev,
177 		const char *phy_id, u32 flags)
178 {
179 	struct bus_type *bus = &mdio_bus_type;
180 	struct phy_device *phydev;
181 	struct device *d;
182 
183 	/* Search the list of PHY devices on the mdio bus for the
184 	 * PHY with the requested name */
185 	d = bus_find_device(bus, NULL, (void *)phy_id, phy_compare_id);
186 
187 	if (d) {
188 		phydev = to_phy_device(d);
189 	} else {
190 		printk(KERN_ERR "%s not found\n", phy_id);
191 		return ERR_PTR(-ENODEV);
192 	}
193 
194 	/* Assume that if there is no driver, that it doesn't
195 	 * exist, and we should use the genphy driver. */
196 	if (NULL == d->driver) {
197 		int err;
198 		down_write(&d->bus->subsys.rwsem);
199 		d->driver = &genphy_driver.driver;
200 
201 		err = d->driver->probe(d);
202 
203 		if (err < 0)
204 			return ERR_PTR(err);
205 
206 		device_bind_driver(d);
207 		up_write(&d->bus->subsys.rwsem);
208 	}
209 
210 	if (phydev->attached_dev) {
211 		printk(KERN_ERR "%s: %s already attached\n",
212 				dev->name, phy_id);
213 		return ERR_PTR(-EBUSY);
214 	}
215 
216 	phydev->attached_dev = dev;
217 
218 	phydev->dev_flags = flags;
219 
220 	return phydev;
221 }
222 EXPORT_SYMBOL(phy_attach);
223 
224 void phy_detach(struct phy_device *phydev)
225 {
226 	phydev->attached_dev = NULL;
227 
228 	/* If the device had no specific driver before (i.e. - it
229 	 * was using the generic driver), we unbind the device
230 	 * from the generic driver so that there's a chance a
231 	 * real driver could be loaded */
232 	if (phydev->dev.driver == &genphy_driver.driver) {
233 		down_write(&phydev->dev.bus->subsys.rwsem);
234 		device_release_driver(&phydev->dev);
235 		up_write(&phydev->dev.bus->subsys.rwsem);
236 	}
237 }
238 EXPORT_SYMBOL(phy_detach);
239 
240 
241 /* Generic PHY support and helper functions */
242 
243 /* genphy_config_advert
244  *
245  * description: Writes MII_ADVERTISE with the appropriate values,
246  *   after sanitizing the values to make sure we only advertise
247  *   what is supported
248  */
249 int genphy_config_advert(struct phy_device *phydev)
250 {
251 	u32 advertise;
252 	int adv;
253 	int err;
254 
255 	/* Only allow advertising what
256 	 * this PHY supports */
257 	phydev->advertising &= phydev->supported;
258 	advertise = phydev->advertising;
259 
260 	/* Setup standard advertisement */
261 	adv = phy_read(phydev, MII_ADVERTISE);
262 
263 	if (adv < 0)
264 		return adv;
265 
266 	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
267 		 ADVERTISE_PAUSE_ASYM);
268 	if (advertise & ADVERTISED_10baseT_Half)
269 		adv |= ADVERTISE_10HALF;
270 	if (advertise & ADVERTISED_10baseT_Full)
271 		adv |= ADVERTISE_10FULL;
272 	if (advertise & ADVERTISED_100baseT_Half)
273 		adv |= ADVERTISE_100HALF;
274 	if (advertise & ADVERTISED_100baseT_Full)
275 		adv |= ADVERTISE_100FULL;
276 	if (advertise & ADVERTISED_Pause)
277 		adv |= ADVERTISE_PAUSE_CAP;
278 	if (advertise & ADVERTISED_Asym_Pause)
279 		adv |= ADVERTISE_PAUSE_ASYM;
280 
281 	err = phy_write(phydev, MII_ADVERTISE, adv);
282 
283 	if (err < 0)
284 		return err;
285 
286 	/* Configure gigabit if it's supported */
287 	if (phydev->supported & (SUPPORTED_1000baseT_Half |
288 				SUPPORTED_1000baseT_Full)) {
289 		adv = phy_read(phydev, MII_CTRL1000);
290 
291 		if (adv < 0)
292 			return adv;
293 
294 		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
295 		if (advertise & SUPPORTED_1000baseT_Half)
296 			adv |= ADVERTISE_1000HALF;
297 		if (advertise & SUPPORTED_1000baseT_Full)
298 			adv |= ADVERTISE_1000FULL;
299 		err = phy_write(phydev, MII_CTRL1000, adv);
300 
301 		if (err < 0)
302 			return err;
303 	}
304 
305 	return adv;
306 }
307 EXPORT_SYMBOL(genphy_config_advert);
308 
309 /* genphy_setup_forced
310  *
311  * description: Configures MII_BMCR to force speed/duplex
312  *   to the values in phydev. Assumes that the values are valid.
313  *   Please see phy_sanitize_settings() */
314 int genphy_setup_forced(struct phy_device *phydev)
315 {
316 	int ctl = BMCR_RESET;
317 
318 	phydev->pause = phydev->asym_pause = 0;
319 
320 	if (SPEED_1000 == phydev->speed)
321 		ctl |= BMCR_SPEED1000;
322 	else if (SPEED_100 == phydev->speed)
323 		ctl |= BMCR_SPEED100;
324 
325 	if (DUPLEX_FULL == phydev->duplex)
326 		ctl |= BMCR_FULLDPLX;
327 
328 	ctl = phy_write(phydev, MII_BMCR, ctl);
329 
330 	if (ctl < 0)
331 		return ctl;
332 
333 	/* We just reset the device, so we'd better configure any
334 	 * settings the PHY requires to operate */
335 	if (phydev->drv->config_init)
336 		ctl = phydev->drv->config_init(phydev);
337 
338 	return ctl;
339 }
340 
341 
342 /* Enable and Restart Autonegotiation */
343 int genphy_restart_aneg(struct phy_device *phydev)
344 {
345 	int ctl;
346 
347 	ctl = phy_read(phydev, MII_BMCR);
348 
349 	if (ctl < 0)
350 		return ctl;
351 
352 	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
353 
354 	/* Don't isolate the PHY if we're negotiating */
355 	ctl &= ~(BMCR_ISOLATE);
356 
357 	ctl = phy_write(phydev, MII_BMCR, ctl);
358 
359 	return ctl;
360 }
361 
362 
363 /* genphy_config_aneg
364  *
365  * description: If auto-negotiation is enabled, we configure the
366  *   advertising, and then restart auto-negotiation.  If it is not
367  *   enabled, then we write the BMCR
368  */
369 int genphy_config_aneg(struct phy_device *phydev)
370 {
371 	int err = 0;
372 
373 	if (AUTONEG_ENABLE == phydev->autoneg) {
374 		err = genphy_config_advert(phydev);
375 
376 		if (err < 0)
377 			return err;
378 
379 		err = genphy_restart_aneg(phydev);
380 	} else
381 		err = genphy_setup_forced(phydev);
382 
383 	return err;
384 }
385 EXPORT_SYMBOL(genphy_config_aneg);
386 
387 /* genphy_update_link
388  *
389  * description: Update the value in phydev->link to reflect the
390  *   current link value.  In order to do this, we need to read
391  *   the status register twice, keeping the second value
392  */
393 int genphy_update_link(struct phy_device *phydev)
394 {
395 	int status;
396 
397 	/* Do a fake read */
398 	status = phy_read(phydev, MII_BMSR);
399 
400 	if (status < 0)
401 		return status;
402 
403 	/* Read link and autonegotiation status */
404 	status = phy_read(phydev, MII_BMSR);
405 
406 	if (status < 0)
407 		return status;
408 
409 	if ((status & BMSR_LSTATUS) == 0)
410 		phydev->link = 0;
411 	else
412 		phydev->link = 1;
413 
414 	return 0;
415 }
416 
417 /* genphy_read_status
418  *
419  * description: Check the link, then figure out the current state
420  *   by comparing what we advertise with what the link partner
421  *   advertises.  Start by checking the gigabit possibilities,
422  *   then move on to 10/100.
423  */
424 int genphy_read_status(struct phy_device *phydev)
425 {
426 	int adv;
427 	int err;
428 	int lpa;
429 	int lpagb = 0;
430 
431 	/* Update the link, but return if there
432 	 * was an error */
433 	err = genphy_update_link(phydev);
434 	if (err)
435 		return err;
436 
437 	if (AUTONEG_ENABLE == phydev->autoneg) {
438 		if (phydev->supported & (SUPPORTED_1000baseT_Half
439 					| SUPPORTED_1000baseT_Full)) {
440 			lpagb = phy_read(phydev, MII_STAT1000);
441 
442 			if (lpagb < 0)
443 				return lpagb;
444 
445 			adv = phy_read(phydev, MII_CTRL1000);
446 
447 			if (adv < 0)
448 				return adv;
449 
450 			lpagb &= adv << 2;
451 		}
452 
453 		lpa = phy_read(phydev, MII_LPA);
454 
455 		if (lpa < 0)
456 			return lpa;
457 
458 		adv = phy_read(phydev, MII_ADVERTISE);
459 
460 		if (adv < 0)
461 			return adv;
462 
463 		lpa &= adv;
464 
465 		phydev->speed = SPEED_10;
466 		phydev->duplex = DUPLEX_HALF;
467 		phydev->pause = phydev->asym_pause = 0;
468 
469 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
470 			phydev->speed = SPEED_1000;
471 
472 			if (lpagb & LPA_1000FULL)
473 				phydev->duplex = DUPLEX_FULL;
474 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
475 			phydev->speed = SPEED_100;
476 
477 			if (lpa & LPA_100FULL)
478 				phydev->duplex = DUPLEX_FULL;
479 		} else
480 			if (lpa & LPA_10FULL)
481 				phydev->duplex = DUPLEX_FULL;
482 
483 		if (phydev->duplex == DUPLEX_FULL){
484 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
485 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
486 		}
487 	} else {
488 		int bmcr = phy_read(phydev, MII_BMCR);
489 		if (bmcr < 0)
490 			return bmcr;
491 
492 		if (bmcr & BMCR_FULLDPLX)
493 			phydev->duplex = DUPLEX_FULL;
494 		else
495 			phydev->duplex = DUPLEX_HALF;
496 
497 		if (bmcr & BMCR_SPEED1000)
498 			phydev->speed = SPEED_1000;
499 		else if (bmcr & BMCR_SPEED100)
500 			phydev->speed = SPEED_100;
501 		else
502 			phydev->speed = SPEED_10;
503 
504 		phydev->pause = phydev->asym_pause = 0;
505 	}
506 
507 	return 0;
508 }
509 EXPORT_SYMBOL(genphy_read_status);
510 
511 static int genphy_config_init(struct phy_device *phydev)
512 {
513 	u32 val;
514 	u32 features;
515 
516 	/* For now, I'll claim that the generic driver supports
517 	 * all possible port types */
518 	features = (SUPPORTED_TP | SUPPORTED_MII
519 			| SUPPORTED_AUI | SUPPORTED_FIBRE |
520 			SUPPORTED_BNC);
521 
522 	/* Do we support autonegotiation? */
523 	val = phy_read(phydev, MII_BMSR);
524 
525 	if (val < 0)
526 		return val;
527 
528 	if (val & BMSR_ANEGCAPABLE)
529 		features |= SUPPORTED_Autoneg;
530 
531 	if (val & BMSR_100FULL)
532 		features |= SUPPORTED_100baseT_Full;
533 	if (val & BMSR_100HALF)
534 		features |= SUPPORTED_100baseT_Half;
535 	if (val & BMSR_10FULL)
536 		features |= SUPPORTED_10baseT_Full;
537 	if (val & BMSR_10HALF)
538 		features |= SUPPORTED_10baseT_Half;
539 
540 	if (val & BMSR_ESTATEN) {
541 		val = phy_read(phydev, MII_ESTATUS);
542 
543 		if (val < 0)
544 			return val;
545 
546 		if (val & ESTATUS_1000_TFULL)
547 			features |= SUPPORTED_1000baseT_Full;
548 		if (val & ESTATUS_1000_THALF)
549 			features |= SUPPORTED_1000baseT_Half;
550 	}
551 
552 	phydev->supported = features;
553 	phydev->advertising = features;
554 
555 	return 0;
556 }
557 
558 
559 /* phy_probe
560  *
561  * description: Take care of setting up the phy_device structure,
562  *   set the state to READY (the driver's init function should
563  *   set it to STARTING if needed).
564  */
565 static int phy_probe(struct device *dev)
566 {
567 	struct phy_device *phydev;
568 	struct phy_driver *phydrv;
569 	struct device_driver *drv;
570 	int err = 0;
571 
572 	phydev = to_phy_device(dev);
573 
574 	/* Make sure the driver is held.
575 	 * XXX -- Is this correct? */
576 	drv = get_driver(phydev->dev.driver);
577 	phydrv = to_phy_driver(drv);
578 	phydev->drv = phydrv;
579 
580 	/* Disable the interrupt if the PHY doesn't support it */
581 	if (!(phydrv->flags & PHY_HAS_INTERRUPT))
582 		phydev->irq = PHY_POLL;
583 
584 	spin_lock(&phydev->lock);
585 
586 	/* Start out supporting everything. Eventually,
587 	 * a controller will attach, and may modify one
588 	 * or both of these values */
589 	phydev->supported = phydrv->features;
590 	phydev->advertising = phydrv->features;
591 
592 	/* Set the state to READY by default */
593 	phydev->state = PHY_READY;
594 
595 	if (phydev->drv->probe)
596 		err = phydev->drv->probe(phydev);
597 
598 	spin_unlock(&phydev->lock);
599 
600 	if (err < 0)
601 		return err;
602 
603 	if (phydev->drv->config_init)
604 		err = phydev->drv->config_init(phydev);
605 
606 	return err;
607 }
608 
609 static int phy_remove(struct device *dev)
610 {
611 	struct phy_device *phydev;
612 
613 	phydev = to_phy_device(dev);
614 
615 	spin_lock(&phydev->lock);
616 	phydev->state = PHY_DOWN;
617 	spin_unlock(&phydev->lock);
618 
619 	if (phydev->drv->remove)
620 		phydev->drv->remove(phydev);
621 
622 	put_driver(dev->driver);
623 	phydev->drv = NULL;
624 
625 	return 0;
626 }
627 
628 int phy_driver_register(struct phy_driver *new_driver)
629 {
630 	int retval;
631 
632 	memset(&new_driver->driver, 0, sizeof(new_driver->driver));
633 	new_driver->driver.name = new_driver->name;
634 	new_driver->driver.bus = &mdio_bus_type;
635 	new_driver->driver.probe = phy_probe;
636 	new_driver->driver.remove = phy_remove;
637 
638 	retval = driver_register(&new_driver->driver);
639 
640 	if (retval) {
641 		printk(KERN_ERR "%s: Error %d in registering driver\n",
642 				new_driver->name, retval);
643 
644 		return retval;
645 	}
646 
647 	pr_info("%s: Registered new driver\n", new_driver->name);
648 
649 	return 0;
650 }
651 EXPORT_SYMBOL(phy_driver_register);
652 
653 void phy_driver_unregister(struct phy_driver *drv)
654 {
655 	driver_unregister(&drv->driver);
656 }
657 EXPORT_SYMBOL(phy_driver_unregister);
658 
659 static struct phy_driver genphy_driver = {
660 	.phy_id		= 0xffffffff,
661 	.phy_id_mask	= 0xffffffff,
662 	.name		= "Generic PHY",
663 	.config_init	= genphy_config_init,
664 	.features	= 0,
665 	.config_aneg	= genphy_config_aneg,
666 	.read_status	= genphy_read_status,
667 	.driver		= {.owner= THIS_MODULE, },
668 };
669 
670 static int __init phy_init(void)
671 {
672 	int rc;
673 
674 	rc = mdio_bus_init();
675 	if (rc)
676 		return rc;
677 
678 	rc = phy_driver_register(&genphy_driver);
679 	if (rc)
680 		mdio_bus_exit();
681 
682 	return rc;
683 }
684 
685 static void __exit phy_exit(void)
686 {
687 	phy_driver_unregister(&genphy_driver);
688 	mdio_bus_exit();
689 }
690 
691 subsys_initcall(phy_init);
692 module_exit(phy_exit);
693