xref: /openbmc/linux/drivers/net/phy/phy_device.c (revision 64c70b1c)
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/string.h>
19 #include <linux/errno.h>
20 #include <linux/unistd.h>
21 #include <linux/slab.h>
22 #include <linux/interrupt.h>
23 #include <linux/init.h>
24 #include <linux/delay.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/skbuff.h>
28 #include <linux/spinlock.h>
29 #include <linux/mm.h>
30 #include <linux/module.h>
31 #include <linux/mii.h>
32 #include <linux/ethtool.h>
33 #include <linux/phy.h>
34 
35 #include <asm/io.h>
36 #include <asm/irq.h>
37 #include <asm/uaccess.h>
38 
39 MODULE_DESCRIPTION("PHY library");
40 MODULE_AUTHOR("Andy Fleming");
41 MODULE_LICENSE("GPL");
42 
43 static struct phy_driver genphy_driver;
44 extern int mdio_bus_init(void);
45 extern void mdio_bus_exit(void);
46 
47 struct phy_device* phy_device_create(struct mii_bus *bus, int addr, int phy_id)
48 {
49 	struct phy_device *dev;
50 	/* We allocate the device, and initialize the
51 	 * default values */
52 	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
53 
54 	if (NULL == dev)
55 		return (struct phy_device*) PTR_ERR((void*)-ENOMEM);
56 
57 	dev->speed = 0;
58 	dev->duplex = -1;
59 	dev->pause = dev->asym_pause = 0;
60 	dev->link = 1;
61 	dev->interface = PHY_INTERFACE_MODE_GMII;
62 
63 	dev->autoneg = AUTONEG_ENABLE;
64 
65 	dev->addr = addr;
66 	dev->phy_id = phy_id;
67 	dev->bus = bus;
68 
69 	dev->state = PHY_DOWN;
70 
71 	spin_lock_init(&dev->lock);
72 
73 	return dev;
74 }
75 EXPORT_SYMBOL(phy_device_create);
76 
77 /**
78  * get_phy_device - reads the specified PHY device and returns its @phy_device struct
79  * @bus: the target MII bus
80  * @addr: PHY address on the MII bus
81  *
82  * Description: Reads the ID registers of the PHY at @addr on the
83  *   @bus, then allocates and returns the phy_device to represent it.
84  */
85 struct phy_device * get_phy_device(struct mii_bus *bus, int addr)
86 {
87 	int phy_reg;
88 	u32 phy_id;
89 	struct phy_device *dev = NULL;
90 
91 	/* Grab the bits from PHYIR1, and put them
92 	 * in the upper half */
93 	phy_reg = bus->read(bus, addr, MII_PHYSID1);
94 
95 	if (phy_reg < 0)
96 		return ERR_PTR(phy_reg);
97 
98 	phy_id = (phy_reg & 0xffff) << 16;
99 
100 	/* Grab the bits from PHYIR2, and put them in the lower half */
101 	phy_reg = bus->read(bus, addr, MII_PHYSID2);
102 
103 	if (phy_reg < 0)
104 		return ERR_PTR(phy_reg);
105 
106 	phy_id |= (phy_reg & 0xffff);
107 
108 	/* If the phy_id is all Fs, there is no device there */
109 	if (0xffffffff == phy_id)
110 		return NULL;
111 
112 	dev = phy_device_create(bus, addr, phy_id);
113 
114 	return dev;
115 }
116 
117 /**
118  * phy_prepare_link - prepares the PHY layer to monitor link status
119  * @phydev: target phy_device struct
120  * @handler: callback function for link status change notifications
121  *
122  * Description: Tells the PHY infrastructure to handle the
123  *   gory details on monitoring link status (whether through
124  *   polling or an interrupt), and to call back to the
125  *   connected device driver when the link status changes.
126  *   If you want to monitor your own link state, don't call
127  *   this function.
128  */
129 void phy_prepare_link(struct phy_device *phydev,
130 		void (*handler)(struct net_device *))
131 {
132 	phydev->adjust_link = handler;
133 }
134 
135 /**
136  * phy_connect - connect an ethernet device to a PHY device
137  * @dev: the network device to connect
138  * @phy_id: the PHY device to connect
139  * @handler: callback function for state change notifications
140  * @flags: PHY device's dev_flags
141  * @interface: PHY device's interface
142  *
143  * Description: Convenience function for connecting ethernet
144  *   devices to PHY devices.  The default behavior is for
145  *   the PHY infrastructure to handle everything, and only notify
146  *   the connected driver when the link status changes.  If you
147  *   don't want, or can't use the provided functionality, you may
148  *   choose to call only the subset of functions which provide
149  *   the desired functionality.
150  */
151 struct phy_device * phy_connect(struct net_device *dev, const char *phy_id,
152 		void (*handler)(struct net_device *), u32 flags,
153 		phy_interface_t interface)
154 {
155 	struct phy_device *phydev;
156 
157 	phydev = phy_attach(dev, phy_id, flags, interface);
158 
159 	if (IS_ERR(phydev))
160 		return phydev;
161 
162 	phy_prepare_link(phydev, handler);
163 
164 	phy_start_machine(phydev, NULL);
165 
166 	if (phydev->irq > 0)
167 		phy_start_interrupts(phydev);
168 
169 	return phydev;
170 }
171 EXPORT_SYMBOL(phy_connect);
172 
173 /**
174  * phy_disconnect - disable interrupts, stop state machine, and detach a PHY device
175  * @phydev: target phy_device struct
176  */
177 void phy_disconnect(struct phy_device *phydev)
178 {
179 	if (phydev->irq > 0)
180 		phy_stop_interrupts(phydev);
181 
182 	phy_stop_machine(phydev);
183 
184 	phydev->adjust_link = NULL;
185 
186 	phy_detach(phydev);
187 }
188 EXPORT_SYMBOL(phy_disconnect);
189 
190 static int phy_compare_id(struct device *dev, void *data)
191 {
192 	return strcmp((char *)data, dev->bus_id) ? 0 : 1;
193 }
194 
195 /**
196  * phy_attach - attach a network device to a particular PHY device
197  * @dev: network device to attach
198  * @phy_id: PHY device to attach
199  * @flags: PHY device's dev_flags
200  * @interface: PHY device's interface
201  *
202  * Description: Called by drivers to attach to a particular PHY
203  *     device. The phy_device is found, and properly hooked up
204  *     to the phy_driver.  If no driver is attached, then the
205  *     genphy_driver is used.  The phy_device is given a ptr to
206  *     the attaching device, and given a callback for link status
207  *     change.  The phy_device is returned to the attaching driver.
208  */
209 struct phy_device *phy_attach(struct net_device *dev,
210 		const char *phy_id, u32 flags, phy_interface_t interface)
211 {
212 	struct bus_type *bus = &mdio_bus_type;
213 	struct phy_device *phydev;
214 	struct device *d;
215 
216 	/* Search the list of PHY devices on the mdio bus for the
217 	 * PHY with the requested name */
218 	d = bus_find_device(bus, NULL, (void *)phy_id, phy_compare_id);
219 
220 	if (d) {
221 		phydev = to_phy_device(d);
222 	} else {
223 		printk(KERN_ERR "%s not found\n", phy_id);
224 		return ERR_PTR(-ENODEV);
225 	}
226 
227 	/* Assume that if there is no driver, that it doesn't
228 	 * exist, and we should use the genphy driver. */
229 	if (NULL == d->driver) {
230 		int err;
231 		d->driver = &genphy_driver.driver;
232 
233 		err = d->driver->probe(d);
234 		if (err >= 0)
235 			err = device_bind_driver(d);
236 
237 		if (err)
238 			return ERR_PTR(err);
239 	}
240 
241 	if (phydev->attached_dev) {
242 		printk(KERN_ERR "%s: %s already attached\n",
243 				dev->name, phy_id);
244 		return ERR_PTR(-EBUSY);
245 	}
246 
247 	phydev->attached_dev = dev;
248 
249 	phydev->dev_flags = flags;
250 
251 	phydev->interface = interface;
252 
253 	/* Do initial configuration here, now that
254 	 * we have certain key parameters
255 	 * (dev_flags and interface) */
256 	if (phydev->drv->config_init) {
257 		int err;
258 
259 		err = phydev->drv->config_init(phydev);
260 
261 		if (err < 0)
262 			return ERR_PTR(err);
263 	}
264 
265 	return phydev;
266 }
267 EXPORT_SYMBOL(phy_attach);
268 
269 /**
270  * phy_detach - detach a PHY device from its network device
271  * @phydev: target phy_device struct
272  */
273 void phy_detach(struct phy_device *phydev)
274 {
275 	phydev->attached_dev = NULL;
276 
277 	/* If the device had no specific driver before (i.e. - it
278 	 * was using the generic driver), we unbind the device
279 	 * from the generic driver so that there's a chance a
280 	 * real driver could be loaded */
281 	if (phydev->dev.driver == &genphy_driver.driver)
282 		device_release_driver(&phydev->dev);
283 }
284 EXPORT_SYMBOL(phy_detach);
285 
286 
287 /* Generic PHY support and helper functions */
288 
289 /**
290  * genphy_config_advert - sanitize and advertise auto-negotation parameters
291  * @phydev: target phy_device struct
292  *
293  * Description: Writes MII_ADVERTISE with the appropriate values,
294  *   after sanitizing the values to make sure we only advertise
295  *   what is supported.
296  */
297 int genphy_config_advert(struct phy_device *phydev)
298 {
299 	u32 advertise;
300 	int adv;
301 	int err;
302 
303 	/* Only allow advertising what
304 	 * this PHY supports */
305 	phydev->advertising &= phydev->supported;
306 	advertise = phydev->advertising;
307 
308 	/* Setup standard advertisement */
309 	adv = phy_read(phydev, MII_ADVERTISE);
310 
311 	if (adv < 0)
312 		return adv;
313 
314 	adv &= ~(ADVERTISE_ALL | ADVERTISE_100BASE4 | ADVERTISE_PAUSE_CAP |
315 		 ADVERTISE_PAUSE_ASYM);
316 	if (advertise & ADVERTISED_10baseT_Half)
317 		adv |= ADVERTISE_10HALF;
318 	if (advertise & ADVERTISED_10baseT_Full)
319 		adv |= ADVERTISE_10FULL;
320 	if (advertise & ADVERTISED_100baseT_Half)
321 		adv |= ADVERTISE_100HALF;
322 	if (advertise & ADVERTISED_100baseT_Full)
323 		adv |= ADVERTISE_100FULL;
324 	if (advertise & ADVERTISED_Pause)
325 		adv |= ADVERTISE_PAUSE_CAP;
326 	if (advertise & ADVERTISED_Asym_Pause)
327 		adv |= ADVERTISE_PAUSE_ASYM;
328 
329 	err = phy_write(phydev, MII_ADVERTISE, adv);
330 
331 	if (err < 0)
332 		return err;
333 
334 	/* Configure gigabit if it's supported */
335 	if (phydev->supported & (SUPPORTED_1000baseT_Half |
336 				SUPPORTED_1000baseT_Full)) {
337 		adv = phy_read(phydev, MII_CTRL1000);
338 
339 		if (adv < 0)
340 			return adv;
341 
342 		adv &= ~(ADVERTISE_1000FULL | ADVERTISE_1000HALF);
343 		if (advertise & SUPPORTED_1000baseT_Half)
344 			adv |= ADVERTISE_1000HALF;
345 		if (advertise & SUPPORTED_1000baseT_Full)
346 			adv |= ADVERTISE_1000FULL;
347 		err = phy_write(phydev, MII_CTRL1000, adv);
348 
349 		if (err < 0)
350 			return err;
351 	}
352 
353 	return adv;
354 }
355 EXPORT_SYMBOL(genphy_config_advert);
356 
357 /**
358  * genphy_setup_forced - configures/forces speed/duplex from @phydev
359  * @phydev: target phy_device struct
360  *
361  * Description: Configures MII_BMCR to force speed/duplex
362  *   to the values in phydev. Assumes that the values are valid.
363  *   Please see phy_sanitize_settings().
364  */
365 int genphy_setup_forced(struct phy_device *phydev)
366 {
367 	int ctl = BMCR_RESET;
368 
369 	phydev->pause = phydev->asym_pause = 0;
370 
371 	if (SPEED_1000 == phydev->speed)
372 		ctl |= BMCR_SPEED1000;
373 	else if (SPEED_100 == phydev->speed)
374 		ctl |= BMCR_SPEED100;
375 
376 	if (DUPLEX_FULL == phydev->duplex)
377 		ctl |= BMCR_FULLDPLX;
378 
379 	ctl = phy_write(phydev, MII_BMCR, ctl);
380 
381 	if (ctl < 0)
382 		return ctl;
383 
384 	/* We just reset the device, so we'd better configure any
385 	 * settings the PHY requires to operate */
386 	if (phydev->drv->config_init)
387 		ctl = phydev->drv->config_init(phydev);
388 
389 	return ctl;
390 }
391 
392 
393 /**
394  * genphy_restart_aneg - Enable and Restart Autonegotiation
395  * @phydev: target phy_device struct
396  */
397 int genphy_restart_aneg(struct phy_device *phydev)
398 {
399 	int ctl;
400 
401 	ctl = phy_read(phydev, MII_BMCR);
402 
403 	if (ctl < 0)
404 		return ctl;
405 
406 	ctl |= (BMCR_ANENABLE | BMCR_ANRESTART);
407 
408 	/* Don't isolate the PHY if we're negotiating */
409 	ctl &= ~(BMCR_ISOLATE);
410 
411 	ctl = phy_write(phydev, MII_BMCR, ctl);
412 
413 	return ctl;
414 }
415 
416 
417 /**
418  * genphy_config_aneg - restart auto-negotiation or write BMCR
419  * @phydev: target phy_device struct
420  *
421  * Description: If auto-negotiation is enabled, we configure the
422  *   advertising, and then restart auto-negotiation.  If it is not
423  *   enabled, then we write the BMCR.
424  */
425 int genphy_config_aneg(struct phy_device *phydev)
426 {
427 	int err = 0;
428 
429 	if (AUTONEG_ENABLE == phydev->autoneg) {
430 		err = genphy_config_advert(phydev);
431 
432 		if (err < 0)
433 			return err;
434 
435 		err = genphy_restart_aneg(phydev);
436 	} else
437 		err = genphy_setup_forced(phydev);
438 
439 	return err;
440 }
441 EXPORT_SYMBOL(genphy_config_aneg);
442 
443 /**
444  * genphy_update_link - update link status in @phydev
445  * @phydev: target phy_device struct
446  *
447  * Description: Update the value in phydev->link to reflect the
448  *   current link value.  In order to do this, we need to read
449  *   the status register twice, keeping the second value.
450  */
451 int genphy_update_link(struct phy_device *phydev)
452 {
453 	int status;
454 
455 	/* Do a fake read */
456 	status = phy_read(phydev, MII_BMSR);
457 
458 	if (status < 0)
459 		return status;
460 
461 	/* Read link and autonegotiation status */
462 	status = phy_read(phydev, MII_BMSR);
463 
464 	if (status < 0)
465 		return status;
466 
467 	if ((status & BMSR_LSTATUS) == 0)
468 		phydev->link = 0;
469 	else
470 		phydev->link = 1;
471 
472 	return 0;
473 }
474 EXPORT_SYMBOL(genphy_update_link);
475 
476 /**
477  * genphy_read_status - check the link status and update current link state
478  * @phydev: target phy_device struct
479  *
480  * Description: Check the link, then figure out the current state
481  *   by comparing what we advertise with what the link partner
482  *   advertises.  Start by checking the gigabit possibilities,
483  *   then move on to 10/100.
484  */
485 int genphy_read_status(struct phy_device *phydev)
486 {
487 	int adv;
488 	int err;
489 	int lpa;
490 	int lpagb = 0;
491 
492 	/* Update the link, but return if there
493 	 * was an error */
494 	err = genphy_update_link(phydev);
495 	if (err)
496 		return err;
497 
498 	if (AUTONEG_ENABLE == phydev->autoneg) {
499 		if (phydev->supported & (SUPPORTED_1000baseT_Half
500 					| SUPPORTED_1000baseT_Full)) {
501 			lpagb = phy_read(phydev, MII_STAT1000);
502 
503 			if (lpagb < 0)
504 				return lpagb;
505 
506 			adv = phy_read(phydev, MII_CTRL1000);
507 
508 			if (adv < 0)
509 				return adv;
510 
511 			lpagb &= adv << 2;
512 		}
513 
514 		lpa = phy_read(phydev, MII_LPA);
515 
516 		if (lpa < 0)
517 			return lpa;
518 
519 		adv = phy_read(phydev, MII_ADVERTISE);
520 
521 		if (adv < 0)
522 			return adv;
523 
524 		lpa &= adv;
525 
526 		phydev->speed = SPEED_10;
527 		phydev->duplex = DUPLEX_HALF;
528 		phydev->pause = phydev->asym_pause = 0;
529 
530 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
531 			phydev->speed = SPEED_1000;
532 
533 			if (lpagb & LPA_1000FULL)
534 				phydev->duplex = DUPLEX_FULL;
535 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
536 			phydev->speed = SPEED_100;
537 
538 			if (lpa & LPA_100FULL)
539 				phydev->duplex = DUPLEX_FULL;
540 		} else
541 			if (lpa & LPA_10FULL)
542 				phydev->duplex = DUPLEX_FULL;
543 
544 		if (phydev->duplex == DUPLEX_FULL){
545 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
546 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
547 		}
548 	} else {
549 		int bmcr = phy_read(phydev, MII_BMCR);
550 		if (bmcr < 0)
551 			return bmcr;
552 
553 		if (bmcr & BMCR_FULLDPLX)
554 			phydev->duplex = DUPLEX_FULL;
555 		else
556 			phydev->duplex = DUPLEX_HALF;
557 
558 		if (bmcr & BMCR_SPEED1000)
559 			phydev->speed = SPEED_1000;
560 		else if (bmcr & BMCR_SPEED100)
561 			phydev->speed = SPEED_100;
562 		else
563 			phydev->speed = SPEED_10;
564 
565 		phydev->pause = phydev->asym_pause = 0;
566 	}
567 
568 	return 0;
569 }
570 EXPORT_SYMBOL(genphy_read_status);
571 
572 static int genphy_config_init(struct phy_device *phydev)
573 {
574 	int val;
575 	u32 features;
576 
577 	/* For now, I'll claim that the generic driver supports
578 	 * all possible port types */
579 	features = (SUPPORTED_TP | SUPPORTED_MII
580 			| SUPPORTED_AUI | SUPPORTED_FIBRE |
581 			SUPPORTED_BNC);
582 
583 	/* Do we support autonegotiation? */
584 	val = phy_read(phydev, MII_BMSR);
585 
586 	if (val < 0)
587 		return val;
588 
589 	if (val & BMSR_ANEGCAPABLE)
590 		features |= SUPPORTED_Autoneg;
591 
592 	if (val & BMSR_100FULL)
593 		features |= SUPPORTED_100baseT_Full;
594 	if (val & BMSR_100HALF)
595 		features |= SUPPORTED_100baseT_Half;
596 	if (val & BMSR_10FULL)
597 		features |= SUPPORTED_10baseT_Full;
598 	if (val & BMSR_10HALF)
599 		features |= SUPPORTED_10baseT_Half;
600 
601 	if (val & BMSR_ESTATEN) {
602 		val = phy_read(phydev, MII_ESTATUS);
603 
604 		if (val < 0)
605 			return val;
606 
607 		if (val & ESTATUS_1000_TFULL)
608 			features |= SUPPORTED_1000baseT_Full;
609 		if (val & ESTATUS_1000_THALF)
610 			features |= SUPPORTED_1000baseT_Half;
611 	}
612 
613 	phydev->supported = features;
614 	phydev->advertising = features;
615 
616 	return 0;
617 }
618 
619 
620 /**
621  * phy_probe - probe and init a PHY device
622  * @dev: device to probe and init
623  *
624  * Description: Take care of setting up the phy_device structure,
625  *   set the state to READY (the driver's init function should
626  *   set it to STARTING if needed).
627  */
628 static int phy_probe(struct device *dev)
629 {
630 	struct phy_device *phydev;
631 	struct phy_driver *phydrv;
632 	struct device_driver *drv;
633 	int err = 0;
634 
635 	phydev = to_phy_device(dev);
636 
637 	/* Make sure the driver is held.
638 	 * XXX -- Is this correct? */
639 	drv = get_driver(phydev->dev.driver);
640 	phydrv = to_phy_driver(drv);
641 	phydev->drv = phydrv;
642 
643 	/* Disable the interrupt if the PHY doesn't support it */
644 	if (!(phydrv->flags & PHY_HAS_INTERRUPT))
645 		phydev->irq = PHY_POLL;
646 
647 	spin_lock(&phydev->lock);
648 
649 	/* Start out supporting everything. Eventually,
650 	 * a controller will attach, and may modify one
651 	 * or both of these values */
652 	phydev->supported = phydrv->features;
653 	phydev->advertising = phydrv->features;
654 
655 	/* Set the state to READY by default */
656 	phydev->state = PHY_READY;
657 
658 	if (phydev->drv->probe)
659 		err = phydev->drv->probe(phydev);
660 
661 	spin_unlock(&phydev->lock);
662 
663 	return err;
664 
665 }
666 
667 static int phy_remove(struct device *dev)
668 {
669 	struct phy_device *phydev;
670 
671 	phydev = to_phy_device(dev);
672 
673 	spin_lock(&phydev->lock);
674 	phydev->state = PHY_DOWN;
675 	spin_unlock(&phydev->lock);
676 
677 	if (phydev->drv->remove)
678 		phydev->drv->remove(phydev);
679 
680 	put_driver(dev->driver);
681 	phydev->drv = NULL;
682 
683 	return 0;
684 }
685 
686 /**
687  * phy_driver_register - register a phy_driver with the PHY layer
688  * @new_driver: new phy_driver to register
689  */
690 int phy_driver_register(struct phy_driver *new_driver)
691 {
692 	int retval;
693 
694 	memset(&new_driver->driver, 0, sizeof(new_driver->driver));
695 	new_driver->driver.name = new_driver->name;
696 	new_driver->driver.bus = &mdio_bus_type;
697 	new_driver->driver.probe = phy_probe;
698 	new_driver->driver.remove = phy_remove;
699 
700 	retval = driver_register(&new_driver->driver);
701 
702 	if (retval) {
703 		printk(KERN_ERR "%s: Error %d in registering driver\n",
704 				new_driver->name, retval);
705 
706 		return retval;
707 	}
708 
709 	pr_info("%s: Registered new driver\n", new_driver->name);
710 
711 	return 0;
712 }
713 EXPORT_SYMBOL(phy_driver_register);
714 
715 void phy_driver_unregister(struct phy_driver *drv)
716 {
717 	driver_unregister(&drv->driver);
718 }
719 EXPORT_SYMBOL(phy_driver_unregister);
720 
721 static struct phy_driver genphy_driver = {
722 	.phy_id		= 0xffffffff,
723 	.phy_id_mask	= 0xffffffff,
724 	.name		= "Generic PHY",
725 	.config_init	= genphy_config_init,
726 	.features	= 0,
727 	.config_aneg	= genphy_config_aneg,
728 	.read_status	= genphy_read_status,
729 	.driver		= {.owner= THIS_MODULE, },
730 };
731 
732 static int __init phy_init(void)
733 {
734 	int rc;
735 
736 	rc = mdio_bus_init();
737 	if (rc)
738 		return rc;
739 
740 	rc = phy_driver_register(&genphy_driver);
741 	if (rc)
742 		mdio_bus_exit();
743 
744 	return rc;
745 }
746 
747 static void __exit phy_exit(void)
748 {
749 	phy_driver_unregister(&genphy_driver);
750 	mdio_bus_exit();
751 }
752 
753 subsys_initcall(phy_init);
754 module_exit(phy_exit);
755