xref: /linux/drivers/net/phy/phy_device.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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/kernel.h>
18 #include <linux/sched.h>
19 #include <linux/string.h>
20 #include <linux/errno.h>
21 #include <linux/unistd.h>
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/init.h>
25 #include <linux/delay.h>
26 #include <linux/netdevice.h>
27 #include <linux/etherdevice.h>
28 #include <linux/skbuff.h>
29 #include <linux/spinlock.h>
30 #include <linux/mm.h>
31 #include <linux/module.h>
32 #include <linux/mii.h>
33 #include <linux/ethtool.h>
34 #include <linux/phy.h>
35 
36 #include <asm/io.h>
37 #include <asm/irq.h>
38 #include <asm/uaccess.h>
39 
40 MODULE_DESCRIPTION("PHY library");
41 MODULE_AUTHOR("Andy Fleming");
42 MODULE_LICENSE("GPL");
43 
44 static struct phy_driver genphy_driver;
45 extern int mdio_bus_init(void);
46 extern void mdio_bus_exit(void);
47 
48 /* get_phy_device
49  *
50  * description: Reads the ID registers of the PHY at addr on the
51  *   bus, then allocates and returns the phy_device to
52  *   represent it.
53  */
54 struct phy_device * get_phy_device(struct mii_bus *bus, int addr)
55 {
56 	int phy_reg;
57 	u32 phy_id;
58 	struct phy_device *dev = NULL;
59 
60 	/* Grab the bits from PHYIR1, and put them
61 	 * in the upper half */
62 	phy_reg = bus->read(bus, addr, MII_PHYSID1);
63 
64 	if (phy_reg < 0)
65 		return ERR_PTR(phy_reg);
66 
67 	phy_id = (phy_reg & 0xffff) << 16;
68 
69 	/* Grab the bits from PHYIR2, and put them in the lower half */
70 	phy_reg = bus->read(bus, addr, MII_PHYSID2);
71 
72 	if (phy_reg < 0)
73 		return ERR_PTR(phy_reg);
74 
75 	phy_id |= (phy_reg & 0xffff);
76 
77 	/* If the phy_id is all Fs, there is no device there */
78 	if (0xffffffff == phy_id)
79 		return NULL;
80 
81 	/* Otherwise, we allocate the device, and initialize the
82 	 * default values */
83 	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
84 
85 	if (NULL == dev)
86 		return ERR_PTR(-ENOMEM);
87 
88 	dev->speed = 0;
89 	dev->duplex = -1;
90 	dev->pause = dev->asym_pause = 0;
91 	dev->link = 1;
92 
93 	dev->autoneg = AUTONEG_ENABLE;
94 
95 	dev->addr = addr;
96 	dev->phy_id = phy_id;
97 	dev->bus = bus;
98 
99 	dev->state = PHY_DOWN;
100 
101 	spin_lock_init(&dev->lock);
102 
103 	return dev;
104 }
105 
106 /* phy_prepare_link:
107  *
108  * description: Tells the PHY infrastructure to handle the
109  *   gory details on monitoring link status (whether through
110  *   polling or an interrupt), and to call back to the
111  *   connected device driver when the link status changes.
112  *   If you want to monitor your own link state, don't call
113  *   this function */
114 void phy_prepare_link(struct phy_device *phydev,
115 		void (*handler)(struct net_device *))
116 {
117 	phydev->adjust_link = handler;
118 }
119 
120 /* phy_connect:
121  *
122  * description: Convenience function for connecting ethernet
123  *   devices to PHY devices.  The default behavior is for
124  *   the PHY infrastructure to handle everything, and only notify
125  *   the connected driver when the link status changes.  If you
126  *   don't want, or can't use the provided functionality, you may
127  *   choose to call only the subset of functions which provide
128  *   the desired functionality.
129  */
130 struct phy_device * phy_connect(struct net_device *dev, const char *phy_id,
131 		void (*handler)(struct net_device *), u32 flags)
132 {
133 	struct phy_device *phydev;
134 
135 	phydev = phy_attach(dev, phy_id, flags);
136 
137 	if (IS_ERR(phydev))
138 		return phydev;
139 
140 	phy_prepare_link(phydev, handler);
141 
142 	phy_start_machine(phydev, NULL);
143 
144 	if (phydev->irq > 0)
145 		phy_start_interrupts(phydev);
146 
147 	return phydev;
148 }
149 EXPORT_SYMBOL(phy_connect);
150 
151 void phy_disconnect(struct phy_device *phydev)
152 {
153 	if (phydev->irq > 0)
154 		phy_stop_interrupts(phydev);
155 
156 	phy_stop_machine(phydev);
157 
158 	phydev->adjust_link = NULL;
159 
160 	phy_detach(phydev);
161 }
162 EXPORT_SYMBOL(phy_disconnect);
163 
164 /* phy_attach:
165  *
166  *   description: Called by drivers to attach to a particular PHY
167  *     device. The phy_device is found, and properly hooked up
168  *     to the phy_driver.  If no driver is attached, then the
169  *     genphy_driver is used.  The phy_device is given a ptr to
170  *     the attaching device, and given a callback for link status
171  *     change.  The phy_device is returned to the attaching
172  *     driver.
173  */
174 static int phy_compare_id(struct device *dev, void *data)
175 {
176 	return strcmp((char *)data, dev->bus_id) ? 0 : 1;
177 }
178 
179 struct phy_device *phy_attach(struct net_device *dev,
180 		const char *phy_id, u32 flags)
181 {
182 	struct bus_type *bus = &mdio_bus_type;
183 	struct phy_device *phydev;
184 	struct device *d;
185 
186 	/* Search the list of PHY devices on the mdio bus for the
187 	 * PHY with the requested name */
188 	d = bus_find_device(bus, NULL, (void *)phy_id, phy_compare_id);
189 
190 	if (d) {
191 		phydev = to_phy_device(d);
192 	} else {
193 		printk(KERN_ERR "%s not found\n", phy_id);
194 		return ERR_PTR(-ENODEV);
195 	}
196 
197 	/* Assume that if there is no driver, that it doesn't
198 	 * exist, and we should use the genphy driver. */
199 	if (NULL == d->driver) {
200 		int err;
201 		down_write(&d->bus->subsys.rwsem);
202 		d->driver = &genphy_driver.driver;
203 
204 		err = d->driver->probe(d);
205 
206 		if (err < 0)
207 			return ERR_PTR(err);
208 
209 		device_bind_driver(d);
210 		up_write(&d->bus->subsys.rwsem);
211 	}
212 
213 	if (phydev->attached_dev) {
214 		printk(KERN_ERR "%s: %s already attached\n",
215 				dev->name, phy_id);
216 		return ERR_PTR(-EBUSY);
217 	}
218 
219 	phydev->attached_dev = dev;
220 
221 	phydev->dev_flags = flags;
222 
223 	return phydev;
224 }
225 EXPORT_SYMBOL(phy_attach);
226 
227 void phy_detach(struct phy_device *phydev)
228 {
229 	phydev->attached_dev = NULL;
230 
231 	/* If the device had no specific driver before (i.e. - it
232 	 * was using the generic driver), we unbind the device
233 	 * from the generic driver so that there's a chance a
234 	 * real driver could be loaded */
235 	if (phydev->dev.driver == &genphy_driver.driver) {
236 		down_write(&phydev->dev.bus->subsys.rwsem);
237 		device_release_driver(&phydev->dev);
238 		up_write(&phydev->dev.bus->subsys.rwsem);
239 	}
240 }
241 EXPORT_SYMBOL(phy_detach);
242 
243 
244 /* Generic PHY support and helper functions */
245 
246 /* genphy_config_advert
247  *
248  * description: Writes MII_ADVERTISE with the appropriate values,
249  *   after sanitizing the values to make sure we only advertise
250  *   what is supported
251  */
252 int genphy_config_advert(struct phy_device *phydev)
253 {
254 	u32 advertise;
255 	int adv;
256 	int err;
257 
258 	/* Only allow advertising what
259 	 * this PHY supports */
260 	phydev->advertising &= phydev->supported;
261 	advertise = phydev->advertising;
262 
263 	/* Setup standard advertisement */
264 	adv = phy_read(phydev, MII_ADVERTISE);
265 
266 	if (adv < 0)
267 		return adv;
268 
269 	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
270 		 ADVERTISE_PAUSE_ASYM);
271 	if (advertise & ADVERTISED_10baseT_Half)
272 		adv |= ADVERTISE_10HALF;
273 	if (advertise & ADVERTISED_10baseT_Full)
274 		adv |= ADVERTISE_10FULL;
275 	if (advertise & ADVERTISED_100baseT_Half)
276 		adv |= ADVERTISE_100HALF;
277 	if (advertise & ADVERTISED_100baseT_Full)
278 		adv |= ADVERTISE_100FULL;
279 	if (advertise & ADVERTISED_Pause)
280 		adv |= ADVERTISE_PAUSE_CAP;
281 	if (advertise & ADVERTISED_Asym_Pause)
282 		adv |= ADVERTISE_PAUSE_ASYM;
283 
284 	err = phy_write(phydev, MII_ADVERTISE, adv);
285 
286 	if (err < 0)
287 		return err;
288 
289 	/* Configure gigabit if it's supported */
290 	if (phydev->supported & (SUPPORTED_1000baseT_Half |
291 				SUPPORTED_1000baseT_Full)) {
292 		adv = phy_read(phydev, MII_CTRL1000);
293 
294 		if (adv < 0)
295 			return adv;
296 
297 		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
298 		if (advertise & SUPPORTED_1000baseT_Half)
299 			adv |= ADVERTISE_1000HALF;
300 		if (advertise & SUPPORTED_1000baseT_Full)
301 			adv |= ADVERTISE_1000FULL;
302 		err = phy_write(phydev, MII_CTRL1000, adv);
303 
304 		if (err < 0)
305 			return err;
306 	}
307 
308 	return adv;
309 }
310 EXPORT_SYMBOL(genphy_config_advert);
311 
312 /* genphy_setup_forced
313  *
314  * description: Configures MII_BMCR to force speed/duplex
315  *   to the values in phydev. Assumes that the values are valid.
316  *   Please see phy_sanitize_settings() */
317 int genphy_setup_forced(struct phy_device *phydev)
318 {
319 	int ctl = BMCR_RESET;
320 
321 	phydev->pause = phydev->asym_pause = 0;
322 
323 	if (SPEED_1000 == phydev->speed)
324 		ctl |= BMCR_SPEED1000;
325 	else if (SPEED_100 == phydev->speed)
326 		ctl |= BMCR_SPEED100;
327 
328 	if (DUPLEX_FULL == phydev->duplex)
329 		ctl |= BMCR_FULLDPLX;
330 
331 	ctl = phy_write(phydev, MII_BMCR, ctl);
332 
333 	if (ctl < 0)
334 		return ctl;
335 
336 	/* We just reset the device, so we'd better configure any
337 	 * settings the PHY requires to operate */
338 	if (phydev->drv->config_init)
339 		ctl = phydev->drv->config_init(phydev);
340 
341 	return ctl;
342 }
343 
344 
345 /* Enable and Restart Autonegotiation */
346 int genphy_restart_aneg(struct phy_device *phydev)
347 {
348 	int ctl;
349 
350 	ctl = phy_read(phydev, MII_BMCR);
351 
352 	if (ctl < 0)
353 		return ctl;
354 
355 	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
356 
357 	/* Don't isolate the PHY if we're negotiating */
358 	ctl &= ~(BMCR_ISOLATE);
359 
360 	ctl = phy_write(phydev, MII_BMCR, ctl);
361 
362 	return ctl;
363 }
364 
365 
366 /* genphy_config_aneg
367  *
368  * description: If auto-negotiation is enabled, we configure the
369  *   advertising, and then restart auto-negotiation.  If it is not
370  *   enabled, then we write the BMCR
371  */
372 int genphy_config_aneg(struct phy_device *phydev)
373 {
374 	int err = 0;
375 
376 	if (AUTONEG_ENABLE == phydev->autoneg) {
377 		err = genphy_config_advert(phydev);
378 
379 		if (err < 0)
380 			return err;
381 
382 		err = genphy_restart_aneg(phydev);
383 	} else
384 		err = genphy_setup_forced(phydev);
385 
386 	return err;
387 }
388 EXPORT_SYMBOL(genphy_config_aneg);
389 
390 /* genphy_update_link
391  *
392  * description: Update the value in phydev->link to reflect the
393  *   current link value.  In order to do this, we need to read
394  *   the status register twice, keeping the second value
395  */
396 int genphy_update_link(struct phy_device *phydev)
397 {
398 	int status;
399 
400 	/* Do a fake read */
401 	status = phy_read(phydev, MII_BMSR);
402 
403 	if (status < 0)
404 		return status;
405 
406 	/* Read link and autonegotiation status */
407 	status = phy_read(phydev, MII_BMSR);
408 
409 	if (status < 0)
410 		return status;
411 
412 	if ((status & BMSR_LSTATUS) == 0)
413 		phydev->link = 0;
414 	else
415 		phydev->link = 1;
416 
417 	return 0;
418 }
419 
420 /* genphy_read_status
421  *
422  * description: Check the link, then figure out the current state
423  *   by comparing what we advertise with what the link partner
424  *   advertises.  Start by checking the gigabit possibilities,
425  *   then move on to 10/100.
426  */
427 int genphy_read_status(struct phy_device *phydev)
428 {
429 	int adv;
430 	int err;
431 	int lpa;
432 	int lpagb = 0;
433 
434 	/* Update the link, but return if there
435 	 * was an error */
436 	err = genphy_update_link(phydev);
437 	if (err)
438 		return err;
439 
440 	if (AUTONEG_ENABLE == phydev->autoneg) {
441 		if (phydev->supported & (SUPPORTED_1000baseT_Half
442 					| SUPPORTED_1000baseT_Full)) {
443 			lpagb = phy_read(phydev, MII_STAT1000);
444 
445 			if (lpagb < 0)
446 				return lpagb;
447 
448 			adv = phy_read(phydev, MII_CTRL1000);
449 
450 			if (adv < 0)
451 				return adv;
452 
453 			lpagb &= adv << 2;
454 		}
455 
456 		lpa = phy_read(phydev, MII_LPA);
457 
458 		if (lpa < 0)
459 			return lpa;
460 
461 		adv = phy_read(phydev, MII_ADVERTISE);
462 
463 		if (adv < 0)
464 			return adv;
465 
466 		lpa &= adv;
467 
468 		phydev->speed = SPEED_10;
469 		phydev->duplex = DUPLEX_HALF;
470 		phydev->pause = phydev->asym_pause = 0;
471 
472 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
473 			phydev->speed = SPEED_1000;
474 
475 			if (lpagb & LPA_1000FULL)
476 				phydev->duplex = DUPLEX_FULL;
477 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
478 			phydev->speed = SPEED_100;
479 
480 			if (lpa & LPA_100FULL)
481 				phydev->duplex = DUPLEX_FULL;
482 		} else
483 			if (lpa & LPA_10FULL)
484 				phydev->duplex = DUPLEX_FULL;
485 
486 		if (phydev->duplex == DUPLEX_FULL){
487 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
488 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
489 		}
490 	} else {
491 		int bmcr = phy_read(phydev, MII_BMCR);
492 		if (bmcr < 0)
493 			return bmcr;
494 
495 		if (bmcr & BMCR_FULLDPLX)
496 			phydev->duplex = DUPLEX_FULL;
497 		else
498 			phydev->duplex = DUPLEX_HALF;
499 
500 		if (bmcr & BMCR_SPEED1000)
501 			phydev->speed = SPEED_1000;
502 		else if (bmcr & BMCR_SPEED100)
503 			phydev->speed = SPEED_100;
504 		else
505 			phydev->speed = SPEED_10;
506 
507 		phydev->pause = phydev->asym_pause = 0;
508 	}
509 
510 	return 0;
511 }
512 EXPORT_SYMBOL(genphy_read_status);
513 
514 static int genphy_config_init(struct phy_device *phydev)
515 {
516 	u32 val;
517 	u32 features;
518 
519 	/* For now, I'll claim that the generic driver supports
520 	 * all possible port types */
521 	features = (SUPPORTED_TP | SUPPORTED_MII
522 			| SUPPORTED_AUI | SUPPORTED_FIBRE |
523 			SUPPORTED_BNC);
524 
525 	/* Do we support autonegotiation? */
526 	val = phy_read(phydev, MII_BMSR);
527 
528 	if (val < 0)
529 		return val;
530 
531 	if (val & BMSR_ANEGCAPABLE)
532 		features |= SUPPORTED_Autoneg;
533 
534 	if (val & BMSR_100FULL)
535 		features |= SUPPORTED_100baseT_Full;
536 	if (val & BMSR_100HALF)
537 		features |= SUPPORTED_100baseT_Half;
538 	if (val & BMSR_10FULL)
539 		features |= SUPPORTED_10baseT_Full;
540 	if (val & BMSR_10HALF)
541 		features |= SUPPORTED_10baseT_Half;
542 
543 	if (val & BMSR_ESTATEN) {
544 		val = phy_read(phydev, MII_ESTATUS);
545 
546 		if (val < 0)
547 			return val;
548 
549 		if (val & ESTATUS_1000_TFULL)
550 			features |= SUPPORTED_1000baseT_Full;
551 		if (val & ESTATUS_1000_THALF)
552 			features |= SUPPORTED_1000baseT_Half;
553 	}
554 
555 	phydev->supported = features;
556 	phydev->advertising = features;
557 
558 	return 0;
559 }
560 
561 
562 /* phy_probe
563  *
564  * description: Take care of setting up the phy_device structure,
565  *   set the state to READY (the driver's init function should
566  *   set it to STARTING if needed).
567  */
568 static int phy_probe(struct device *dev)
569 {
570 	struct phy_device *phydev;
571 	struct phy_driver *phydrv;
572 	struct device_driver *drv;
573 	int err = 0;
574 
575 	phydev = to_phy_device(dev);
576 
577 	/* Make sure the driver is held.
578 	 * XXX -- Is this correct? */
579 	drv = get_driver(phydev->dev.driver);
580 	phydrv = to_phy_driver(drv);
581 	phydev->drv = phydrv;
582 
583 	/* Disable the interrupt if the PHY doesn't support it */
584 	if (!(phydrv->flags & PHY_HAS_INTERRUPT))
585 		phydev->irq = PHY_POLL;
586 
587 	spin_lock(&phydev->lock);
588 
589 	/* Start out supporting everything. Eventually,
590 	 * a controller will attach, and may modify one
591 	 * or both of these values */
592 	phydev->supported = phydrv->features;
593 	phydev->advertising = phydrv->features;
594 
595 	/* Set the state to READY by default */
596 	phydev->state = PHY_READY;
597 
598 	if (phydev->drv->probe)
599 		err = phydev->drv->probe(phydev);
600 
601 	spin_unlock(&phydev->lock);
602 
603 	if (err < 0)
604 		return err;
605 
606 	if (phydev->drv->config_init)
607 		err = phydev->drv->config_init(phydev);
608 
609 	return err;
610 }
611 
612 static int phy_remove(struct device *dev)
613 {
614 	struct phy_device *phydev;
615 
616 	phydev = to_phy_device(dev);
617 
618 	spin_lock(&phydev->lock);
619 	phydev->state = PHY_DOWN;
620 	spin_unlock(&phydev->lock);
621 
622 	if (phydev->drv->remove)
623 		phydev->drv->remove(phydev);
624 
625 	put_driver(dev->driver);
626 	phydev->drv = NULL;
627 
628 	return 0;
629 }
630 
631 int phy_driver_register(struct phy_driver *new_driver)
632 {
633 	int retval;
634 
635 	memset(&new_driver->driver, 0, sizeof(new_driver->driver));
636 	new_driver->driver.name = new_driver->name;
637 	new_driver->driver.bus = &mdio_bus_type;
638 	new_driver->driver.probe = phy_probe;
639 	new_driver->driver.remove = phy_remove;
640 
641 	retval = driver_register(&new_driver->driver);
642 
643 	if (retval) {
644 		printk(KERN_ERR "%s: Error %d in registering driver\n",
645 				new_driver->name, retval);
646 
647 		return retval;
648 	}
649 
650 	pr_info("%s: Registered new driver\n", new_driver->name);
651 
652 	return 0;
653 }
654 EXPORT_SYMBOL(phy_driver_register);
655 
656 void phy_driver_unregister(struct phy_driver *drv)
657 {
658 	driver_unregister(&drv->driver);
659 }
660 EXPORT_SYMBOL(phy_driver_unregister);
661 
662 static struct phy_driver genphy_driver = {
663 	.phy_id		= 0xffffffff,
664 	.phy_id_mask	= 0xffffffff,
665 	.name		= "Generic PHY",
666 	.config_init	= genphy_config_init,
667 	.features	= 0,
668 	.config_aneg	= genphy_config_aneg,
669 	.read_status	= genphy_read_status,
670 	.driver		= {.owner= THIS_MODULE, },
671 };
672 
673 static int __init phy_init(void)
674 {
675 	int rc;
676 
677 	rc = mdio_bus_init();
678 	if (rc)
679 		return rc;
680 
681 	rc = phy_driver_register(&genphy_driver);
682 	if (rc)
683 		mdio_bus_exit();
684 
685 	return rc;
686 }
687 
688 static void __exit phy_exit(void)
689 {
690 	phy_driver_unregister(&genphy_driver);
691 	mdio_bus_exit();
692 }
693 
694 subsys_initcall(phy_init);
695 module_exit(phy_exit);
696