xref: /openbmc/linux/drivers/net/phy/phy_device.c (revision 87c2ce3b)
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 MODULE_DESCRIPTION("PHY library");
42 MODULE_AUTHOR("Andy Fleming");
43 MODULE_LICENSE("GPL");
44 
45 static struct phy_driver genphy_driver;
46 extern int mdio_bus_init(void);
47 extern void mdio_bus_exit(void);
48 
49 /* get_phy_device
50  *
51  * description: Reads the ID registers of the PHY at addr on the
52  *   bus, then allocates and returns the phy_device to
53  *   represent it.
54  */
55 struct phy_device * get_phy_device(struct mii_bus *bus, int addr)
56 {
57 	int phy_reg;
58 	u32 phy_id;
59 	struct phy_device *dev = NULL;
60 
61 	/* Grab the bits from PHYIR1, and put them
62 	 * in the upper half */
63 	phy_reg = bus->read(bus, addr, MII_PHYSID1);
64 
65 	if (phy_reg < 0)
66 		return ERR_PTR(phy_reg);
67 
68 	phy_id = (phy_reg & 0xffff) << 16;
69 
70 	/* Grab the bits from PHYIR2, and put them in the lower half */
71 	phy_reg = bus->read(bus, addr, MII_PHYSID2);
72 
73 	if (phy_reg < 0)
74 		return ERR_PTR(phy_reg);
75 
76 	phy_id |= (phy_reg & 0xffff);
77 
78 	/* If the phy_id is all Fs, there is no device there */
79 	if (0xffffffff == phy_id)
80 		return NULL;
81 
82 	/* Otherwise, we allocate the device, and initialize the
83 	 * default values */
84 	dev = kcalloc(1, sizeof(*dev), GFP_KERNEL);
85 
86 	if (NULL == dev)
87 		return ERR_PTR(-ENOMEM);
88 
89 	dev->speed = 0;
90 	dev->duplex = -1;
91 	dev->pause = dev->asym_pause = 0;
92 	dev->link = 1;
93 
94 	dev->autoneg = AUTONEG_ENABLE;
95 
96 	dev->addr = addr;
97 	dev->phy_id = phy_id;
98 	dev->bus = bus;
99 
100 	dev->state = PHY_DOWN;
101 
102 	spin_lock_init(&dev->lock);
103 
104 	return dev;
105 }
106 
107 /* phy_prepare_link:
108  *
109  * description: Tells the PHY infrastructure to handle the
110  *   gory details on monitoring link status (whether through
111  *   polling or an interrupt), and to call back to the
112  *   connected device driver when the link status changes.
113  *   If you want to monitor your own link state, don't call
114  *   this function */
115 void phy_prepare_link(struct phy_device *phydev,
116 		void (*handler)(struct net_device *))
117 {
118 	phydev->adjust_link = handler;
119 }
120 
121 /* phy_connect:
122  *
123  * description: Convenience function for connecting ethernet
124  *   devices to PHY devices.  The default behavior is for
125  *   the PHY infrastructure to handle everything, and only notify
126  *   the connected driver when the link status changes.  If you
127  *   don't want, or can't use the provided functionality, you may
128  *   choose to call only the subset of functions which provide
129  *   the desired functionality.
130  */
131 struct phy_device * phy_connect(struct net_device *dev, const char *phy_id,
132 		void (*handler)(struct net_device *), u32 flags)
133 {
134 	struct phy_device *phydev;
135 
136 	phydev = phy_attach(dev, phy_id, flags);
137 
138 	if (IS_ERR(phydev))
139 		return phydev;
140 
141 	phy_prepare_link(phydev, handler);
142 
143 	phy_start_machine(phydev, NULL);
144 
145 	if (phydev->irq > 0)
146 		phy_start_interrupts(phydev);
147 
148 	return phydev;
149 }
150 EXPORT_SYMBOL(phy_connect);
151 
152 void phy_disconnect(struct phy_device *phydev)
153 {
154 	if (phydev->irq > 0)
155 		phy_stop_interrupts(phydev);
156 
157 	phy_stop_machine(phydev);
158 
159 	phydev->adjust_link = NULL;
160 
161 	phy_detach(phydev);
162 }
163 EXPORT_SYMBOL(phy_disconnect);
164 
165 /* phy_attach:
166  *
167  *   description: Called by drivers to attach to a particular PHY
168  *     device. The phy_device is found, and properly hooked up
169  *     to the phy_driver.  If no driver is attached, then the
170  *     genphy_driver is used.  The phy_device is given a ptr to
171  *     the attaching device, and given a callback for link status
172  *     change.  The phy_device is returned to the attaching
173  *     driver.
174  */
175 static int phy_compare_id(struct device *dev, void *data)
176 {
177 	return strcmp((char *)data, dev->bus_id) ? 0 : 1;
178 }
179 
180 struct phy_device *phy_attach(struct net_device *dev,
181 		const char *phy_id, u32 flags)
182 {
183 	struct bus_type *bus = &mdio_bus_type;
184 	struct phy_device *phydev;
185 	struct device *d;
186 
187 	/* Search the list of PHY devices on the mdio bus for the
188 	 * PHY with the requested name */
189 	d = bus_find_device(bus, NULL, (void *)phy_id, phy_compare_id);
190 
191 	if (d) {
192 		phydev = to_phy_device(d);
193 	} else {
194 		printk(KERN_ERR "%s not found\n", phy_id);
195 		return ERR_PTR(-ENODEV);
196 	}
197 
198 	/* Assume that if there is no driver, that it doesn't
199 	 * exist, and we should use the genphy driver. */
200 	if (NULL == d->driver) {
201 		int err;
202 		down_write(&d->bus->subsys.rwsem);
203 		d->driver = &genphy_driver.driver;
204 
205 		err = d->driver->probe(d);
206 
207 		if (err < 0)
208 			return ERR_PTR(err);
209 
210 		device_bind_driver(d);
211 		up_write(&d->bus->subsys.rwsem);
212 	}
213 
214 	if (phydev->attached_dev) {
215 		printk(KERN_ERR "%s: %s already attached\n",
216 				dev->name, phy_id);
217 		return ERR_PTR(-EBUSY);
218 	}
219 
220 	phydev->attached_dev = dev;
221 
222 	phydev->dev_flags = flags;
223 
224 	return phydev;
225 }
226 EXPORT_SYMBOL(phy_attach);
227 
228 void phy_detach(struct phy_device *phydev)
229 {
230 	phydev->attached_dev = NULL;
231 
232 	/* If the device had no specific driver before (i.e. - it
233 	 * was using the generic driver), we unbind the device
234 	 * from the generic driver so that there's a chance a
235 	 * real driver could be loaded */
236 	if (phydev->dev.driver == &genphy_driver.driver) {
237 		down_write(&phydev->dev.bus->subsys.rwsem);
238 		device_release_driver(&phydev->dev);
239 		up_write(&phydev->dev.bus->subsys.rwsem);
240 	}
241 }
242 EXPORT_SYMBOL(phy_detach);
243 
244 
245 /* Generic PHY support and helper functions */
246 
247 /* genphy_config_advert
248  *
249  * description: Writes MII_ADVERTISE with the appropriate values,
250  *   after sanitizing the values to make sure we only advertise
251  *   what is supported
252  */
253 int genphy_config_advert(struct phy_device *phydev)
254 {
255 	u32 advertise;
256 	int adv;
257 	int err;
258 
259 	/* Only allow advertising what
260 	 * this PHY supports */
261 	phydev->advertising &= phydev->supported;
262 	advertise = phydev->advertising;
263 
264 	/* Setup standard advertisement */
265 	adv = phy_read(phydev, MII_ADVERTISE);
266 
267 	if (adv < 0)
268 		return adv;
269 
270 	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
271 		 ADVERTISE_PAUSE_ASYM);
272 	if (advertise & ADVERTISED_10baseT_Half)
273 		adv |= ADVERTISE_10HALF;
274 	if (advertise & ADVERTISED_10baseT_Full)
275 		adv |= ADVERTISE_10FULL;
276 	if (advertise & ADVERTISED_100baseT_Half)
277 		adv |= ADVERTISE_100HALF;
278 	if (advertise & ADVERTISED_100baseT_Full)
279 		adv |= ADVERTISE_100FULL;
280 	if (advertise & ADVERTISED_Pause)
281 		adv |= ADVERTISE_PAUSE_CAP;
282 	if (advertise & ADVERTISED_Asym_Pause)
283 		adv |= ADVERTISE_PAUSE_ASYM;
284 
285 	err = phy_write(phydev, MII_ADVERTISE, adv);
286 
287 	if (err < 0)
288 		return err;
289 
290 	/* Configure gigabit if it's supported */
291 	if (phydev->supported & (SUPPORTED_1000baseT_Half |
292 				SUPPORTED_1000baseT_Full)) {
293 		adv = phy_read(phydev, MII_CTRL1000);
294 
295 		if (adv < 0)
296 			return adv;
297 
298 		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
299 		if (advertise & SUPPORTED_1000baseT_Half)
300 			adv |= ADVERTISE_1000HALF;
301 		if (advertise & SUPPORTED_1000baseT_Full)
302 			adv |= ADVERTISE_1000FULL;
303 		err = phy_write(phydev, MII_CTRL1000, adv);
304 
305 		if (err < 0)
306 			return err;
307 	}
308 
309 	return adv;
310 }
311 EXPORT_SYMBOL(genphy_config_advert);
312 
313 /* genphy_setup_forced
314  *
315  * description: Configures MII_BMCR to force speed/duplex
316  *   to the values in phydev. Assumes that the values are valid.
317  *   Please see phy_sanitize_settings() */
318 int genphy_setup_forced(struct phy_device *phydev)
319 {
320 	int ctl = BMCR_RESET;
321 
322 	phydev->pause = phydev->asym_pause = 0;
323 
324 	if (SPEED_1000 == phydev->speed)
325 		ctl |= BMCR_SPEED1000;
326 	else if (SPEED_100 == phydev->speed)
327 		ctl |= BMCR_SPEED100;
328 
329 	if (DUPLEX_FULL == phydev->duplex)
330 		ctl |= BMCR_FULLDPLX;
331 
332 	ctl = phy_write(phydev, MII_BMCR, ctl);
333 
334 	if (ctl < 0)
335 		return ctl;
336 
337 	/* We just reset the device, so we'd better configure any
338 	 * settings the PHY requires to operate */
339 	if (phydev->drv->config_init)
340 		ctl = phydev->drv->config_init(phydev);
341 
342 	return ctl;
343 }
344 
345 
346 /* Enable and Restart Autonegotiation */
347 int genphy_restart_aneg(struct phy_device *phydev)
348 {
349 	int ctl;
350 
351 	ctl = phy_read(phydev, MII_BMCR);
352 
353 	if (ctl < 0)
354 		return ctl;
355 
356 	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
357 
358 	/* Don't isolate the PHY if we're negotiating */
359 	ctl &= ~(BMCR_ISOLATE);
360 
361 	ctl = phy_write(phydev, MII_BMCR, ctl);
362 
363 	return ctl;
364 }
365 
366 
367 /* genphy_config_aneg
368  *
369  * description: If auto-negotiation is enabled, we configure the
370  *   advertising, and then restart auto-negotiation.  If it is not
371  *   enabled, then we write the BMCR
372  */
373 int genphy_config_aneg(struct phy_device *phydev)
374 {
375 	int err = 0;
376 
377 	if (AUTONEG_ENABLE == phydev->autoneg) {
378 		err = genphy_config_advert(phydev);
379 
380 		if (err < 0)
381 			return err;
382 
383 		err = genphy_restart_aneg(phydev);
384 	} else
385 		err = genphy_setup_forced(phydev);
386 
387 	return err;
388 }
389 EXPORT_SYMBOL(genphy_config_aneg);
390 
391 /* genphy_update_link
392  *
393  * description: Update the value in phydev->link to reflect the
394  *   current link value.  In order to do this, we need to read
395  *   the status register twice, keeping the second value
396  */
397 int genphy_update_link(struct phy_device *phydev)
398 {
399 	int status;
400 
401 	/* Do a fake read */
402 	status = phy_read(phydev, MII_BMSR);
403 
404 	if (status < 0)
405 		return status;
406 
407 	/* Read link and autonegotiation status */
408 	status = phy_read(phydev, MII_BMSR);
409 
410 	if (status < 0)
411 		return status;
412 
413 	if ((status & BMSR_LSTATUS) == 0)
414 		phydev->link = 0;
415 	else
416 		phydev->link = 1;
417 
418 	return 0;
419 }
420 
421 /* genphy_read_status
422  *
423  * description: Check the link, then figure out the current state
424  *   by comparing what we advertise with what the link partner
425  *   advertises.  Start by checking the gigabit possibilities,
426  *   then move on to 10/100.
427  */
428 int genphy_read_status(struct phy_device *phydev)
429 {
430 	int adv;
431 	int err;
432 	int lpa;
433 	int lpagb = 0;
434 
435 	/* Update the link, but return if there
436 	 * was an error */
437 	err = genphy_update_link(phydev);
438 	if (err)
439 		return err;
440 
441 	if (AUTONEG_ENABLE == phydev->autoneg) {
442 		if (phydev->supported & (SUPPORTED_1000baseT_Half
443 					| SUPPORTED_1000baseT_Full)) {
444 			lpagb = phy_read(phydev, MII_STAT1000);
445 
446 			if (lpagb < 0)
447 				return lpagb;
448 
449 			adv = phy_read(phydev, MII_CTRL1000);
450 
451 			if (adv < 0)
452 				return adv;
453 
454 			lpagb &= adv << 2;
455 		}
456 
457 		lpa = phy_read(phydev, MII_LPA);
458 
459 		if (lpa < 0)
460 			return lpa;
461 
462 		adv = phy_read(phydev, MII_ADVERTISE);
463 
464 		if (adv < 0)
465 			return adv;
466 
467 		lpa &= adv;
468 
469 		phydev->speed = SPEED_10;
470 		phydev->duplex = DUPLEX_HALF;
471 		phydev->pause = phydev->asym_pause = 0;
472 
473 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
474 			phydev->speed = SPEED_1000;
475 
476 			if (lpagb & LPA_1000FULL)
477 				phydev->duplex = DUPLEX_FULL;
478 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
479 			phydev->speed = SPEED_100;
480 
481 			if (lpa & LPA_100FULL)
482 				phydev->duplex = DUPLEX_FULL;
483 		} else
484 			if (lpa & LPA_10FULL)
485 				phydev->duplex = DUPLEX_FULL;
486 
487 		if (phydev->duplex == DUPLEX_FULL){
488 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
489 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
490 		}
491 	} else {
492 		int bmcr = phy_read(phydev, MII_BMCR);
493 		if (bmcr < 0)
494 			return bmcr;
495 
496 		if (bmcr & BMCR_FULLDPLX)
497 			phydev->duplex = DUPLEX_FULL;
498 		else
499 			phydev->duplex = DUPLEX_HALF;
500 
501 		if (bmcr & BMCR_SPEED1000)
502 			phydev->speed = SPEED_1000;
503 		else if (bmcr & BMCR_SPEED100)
504 			phydev->speed = SPEED_100;
505 		else
506 			phydev->speed = SPEED_10;
507 
508 		phydev->pause = phydev->asym_pause = 0;
509 	}
510 
511 	return 0;
512 }
513 EXPORT_SYMBOL(genphy_read_status);
514 
515 static int genphy_config_init(struct phy_device *phydev)
516 {
517 	u32 val;
518 	u32 features;
519 
520 	/* For now, I'll claim that the generic driver supports
521 	 * all possible port types */
522 	features = (SUPPORTED_TP | SUPPORTED_MII
523 			| SUPPORTED_AUI | SUPPORTED_FIBRE |
524 			SUPPORTED_BNC);
525 
526 	/* Do we support autonegotiation? */
527 	val = phy_read(phydev, MII_BMSR);
528 
529 	if (val < 0)
530 		return val;
531 
532 	if (val & BMSR_ANEGCAPABLE)
533 		features |= SUPPORTED_Autoneg;
534 
535 	if (val & BMSR_100FULL)
536 		features |= SUPPORTED_100baseT_Full;
537 	if (val & BMSR_100HALF)
538 		features |= SUPPORTED_100baseT_Half;
539 	if (val & BMSR_10FULL)
540 		features |= SUPPORTED_10baseT_Full;
541 	if (val & BMSR_10HALF)
542 		features |= SUPPORTED_10baseT_Half;
543 
544 	if (val & BMSR_ESTATEN) {
545 		val = phy_read(phydev, MII_ESTATUS);
546 
547 		if (val < 0)
548 			return val;
549 
550 		if (val & ESTATUS_1000_TFULL)
551 			features |= SUPPORTED_1000baseT_Full;
552 		if (val & ESTATUS_1000_THALF)
553 			features |= SUPPORTED_1000baseT_Half;
554 	}
555 
556 	phydev->supported = features;
557 	phydev->advertising = features;
558 
559 	return 0;
560 }
561 
562 
563 /* phy_probe
564  *
565  * description: Take care of setting up the phy_device structure,
566  *   set the state to READY (the driver's init function should
567  *   set it to STARTING if needed).
568  */
569 static int phy_probe(struct device *dev)
570 {
571 	struct phy_device *phydev;
572 	struct phy_driver *phydrv;
573 	struct device_driver *drv;
574 	int err = 0;
575 
576 	phydev = to_phy_device(dev);
577 
578 	/* Make sure the driver is held.
579 	 * XXX -- Is this correct? */
580 	drv = get_driver(phydev->dev.driver);
581 	phydrv = to_phy_driver(drv);
582 	phydev->drv = phydrv;
583 
584 	/* Disable the interrupt if the PHY doesn't support it */
585 	if (!(phydrv->flags & PHY_HAS_INTERRUPT))
586 		phydev->irq = PHY_POLL;
587 
588 	spin_lock(&phydev->lock);
589 
590 	/* Start out supporting everything. Eventually,
591 	 * a controller will attach, and may modify one
592 	 * or both of these values */
593 	phydev->supported = phydrv->features;
594 	phydev->advertising = phydrv->features;
595 
596 	/* Set the state to READY by default */
597 	phydev->state = PHY_READY;
598 
599 	if (phydev->drv->probe)
600 		err = phydev->drv->probe(phydev);
601 
602 	spin_unlock(&phydev->lock);
603 
604 	if (err < 0)
605 		return err;
606 
607 	if (phydev->drv->config_init)
608 		err = phydev->drv->config_init(phydev);
609 
610 	return err;
611 }
612 
613 static int phy_remove(struct device *dev)
614 {
615 	struct phy_device *phydev;
616 
617 	phydev = to_phy_device(dev);
618 
619 	spin_lock(&phydev->lock);
620 	phydev->state = PHY_DOWN;
621 	spin_unlock(&phydev->lock);
622 
623 	if (phydev->drv->remove)
624 		phydev->drv->remove(phydev);
625 
626 	put_driver(dev->driver);
627 	phydev->drv = NULL;
628 
629 	return 0;
630 }
631 
632 int phy_driver_register(struct phy_driver *new_driver)
633 {
634 	int retval;
635 
636 	memset(&new_driver->driver, 0, sizeof(new_driver->driver));
637 	new_driver->driver.name = new_driver->name;
638 	new_driver->driver.bus = &mdio_bus_type;
639 	new_driver->driver.probe = phy_probe;
640 	new_driver->driver.remove = phy_remove;
641 
642 	retval = driver_register(&new_driver->driver);
643 
644 	if (retval) {
645 		printk(KERN_ERR "%s: Error %d in registering driver\n",
646 				new_driver->name, retval);
647 
648 		return retval;
649 	}
650 
651 	pr_info("%s: Registered new driver\n", new_driver->name);
652 
653 	return 0;
654 }
655 EXPORT_SYMBOL(phy_driver_register);
656 
657 void phy_driver_unregister(struct phy_driver *drv)
658 {
659 	driver_unregister(&drv->driver);
660 }
661 EXPORT_SYMBOL(phy_driver_unregister);
662 
663 static struct phy_driver genphy_driver = {
664 	.phy_id		= 0xffffffff,
665 	.phy_id_mask	= 0xffffffff,
666 	.name		= "Generic PHY",
667 	.config_init	= genphy_config_init,
668 	.features	= 0,
669 	.config_aneg	= genphy_config_aneg,
670 	.read_status	= genphy_read_status,
671 	.driver		= {.owner= THIS_MODULE, },
672 };
673 
674 static int __init phy_init(void)
675 {
676 	int rc;
677 
678 	rc = mdio_bus_init();
679 	if (rc)
680 		return rc;
681 
682 	rc = phy_driver_register(&genphy_driver);
683 	if (rc)
684 		mdio_bus_exit();
685 
686 	return rc;
687 }
688 
689 static void __exit phy_exit(void)
690 {
691 	phy_driver_unregister(&genphy_driver);
692 	mdio_bus_exit();
693 }
694 
695 subsys_initcall(phy_init);
696 module_exit(phy_exit);
697