xref: /linux/drivers/net/phy/sfp-bus.c (revision 3f41368fbfe1b3d5922d317fe1a0a0cab6846802)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/export.h>
3 #include <linux/kref.h>
4 #include <linux/list.h>
5 #include <linux/mutex.h>
6 #include <linux/phylink.h>
7 #include <linux/property.h>
8 #include <linux/rtnetlink.h>
9 #include <linux/slab.h>
10 
11 #include "sfp.h"
12 
13 /**
14  * struct sfp_bus - internal representation of a sfp bus
15  */
16 struct sfp_bus {
17 	/* private: */
18 	struct kref kref;
19 	struct list_head node;
20 	const struct fwnode_handle *fwnode;
21 
22 	const struct sfp_socket_ops *socket_ops;
23 	struct device *sfp_dev;
24 	struct sfp *sfp;
25 	const struct sfp_quirk *sfp_quirk;
26 
27 	const struct sfp_upstream_ops *upstream_ops;
28 	void *upstream;
29 	struct phy_device *phydev;
30 
31 	bool registered;
32 	bool started;
33 };
34 
35 /**
36  * sfp_parse_port() - Parse the EEPROM base ID, setting the port type
37  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
38  * @id: a pointer to the module's &struct sfp_eeprom_id
39  * @support: optional pointer to an array of unsigned long for the
40  *   ethtool support mask
41  *
42  * Parse the EEPROM identification given in @id, and return one of
43  * %PORT_TP, %PORT_FIBRE or %PORT_OTHER. If @support is non-%NULL,
44  * also set the ethtool %ETHTOOL_LINK_MODE_xxx_BIT corresponding with
45  * the connector type.
46  *
47  * If the port type is not known, returns %PORT_OTHER.
48  */
49 int sfp_parse_port(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
50 		   unsigned long *support)
51 {
52 	int port;
53 
54 	/* port is the physical connector, set this from the connector field. */
55 	switch (id->base.connector) {
56 	case SFF8024_CONNECTOR_SC:
57 	case SFF8024_CONNECTOR_FIBERJACK:
58 	case SFF8024_CONNECTOR_LC:
59 	case SFF8024_CONNECTOR_MT_RJ:
60 	case SFF8024_CONNECTOR_MU:
61 	case SFF8024_CONNECTOR_OPTICAL_PIGTAIL:
62 	case SFF8024_CONNECTOR_MPO_1X12:
63 	case SFF8024_CONNECTOR_MPO_2X16:
64 		port = PORT_FIBRE;
65 		break;
66 
67 	case SFF8024_CONNECTOR_RJ45:
68 		port = PORT_TP;
69 		break;
70 
71 	case SFF8024_CONNECTOR_COPPER_PIGTAIL:
72 		port = PORT_DA;
73 		break;
74 
75 	case SFF8024_CONNECTOR_UNSPEC:
76 		if (id->base.e1000_base_t) {
77 			port = PORT_TP;
78 			break;
79 		}
80 		fallthrough;
81 	case SFF8024_CONNECTOR_SG: /* guess */
82 	case SFF8024_CONNECTOR_HSSDC_II:
83 	case SFF8024_CONNECTOR_NOSEPARATE:
84 	case SFF8024_CONNECTOR_MXC_2X16:
85 		port = PORT_OTHER;
86 		break;
87 	default:
88 		dev_warn(bus->sfp_dev, "SFP: unknown connector id 0x%02x\n",
89 			 id->base.connector);
90 		port = PORT_OTHER;
91 		break;
92 	}
93 
94 	if (support) {
95 		switch (port) {
96 		case PORT_FIBRE:
97 			phylink_set(support, FIBRE);
98 			break;
99 
100 		case PORT_TP:
101 			phylink_set(support, TP);
102 			break;
103 		}
104 	}
105 
106 	return port;
107 }
108 EXPORT_SYMBOL_GPL(sfp_parse_port);
109 
110 /**
111  * sfp_may_have_phy() - indicate whether the module may have a PHY
112  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
113  * @id: a pointer to the module's &struct sfp_eeprom_id
114  *
115  * Parse the EEPROM identification given in @id, and return whether
116  * this module may have a PHY.
117  */
118 bool sfp_may_have_phy(struct sfp_bus *bus, const struct sfp_eeprom_id *id)
119 {
120 	if (id->base.e1000_base_t)
121 		return true;
122 
123 	if (id->base.phys_id != SFF8024_ID_DWDM_SFP) {
124 		switch (id->base.extended_cc) {
125 		case SFF8024_ECC_10GBASE_T_SFI:
126 		case SFF8024_ECC_10GBASE_T_SR:
127 		case SFF8024_ECC_5GBASE_T:
128 		case SFF8024_ECC_2_5GBASE_T:
129 			return true;
130 		}
131 	}
132 
133 	return false;
134 }
135 EXPORT_SYMBOL_GPL(sfp_may_have_phy);
136 
137 /**
138  * sfp_parse_support() - Parse the eeprom id for supported link modes
139  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
140  * @id: a pointer to the module's &struct sfp_eeprom_id
141  * @support: pointer to an array of unsigned long for the ethtool support mask
142  * @interfaces: pointer to an array of unsigned long for phy interface modes
143  *		mask
144  *
145  * Parse the EEPROM identification information and derive the supported
146  * ethtool link modes for the module.
147  */
148 void sfp_parse_support(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
149 		       unsigned long *support, unsigned long *interfaces)
150 {
151 	unsigned int br_min, br_nom, br_max;
152 	__ETHTOOL_DECLARE_LINK_MODE_MASK(modes) = { 0, };
153 
154 	/* Decode the bitrate information to MBd */
155 	br_min = br_nom = br_max = 0;
156 	if (id->base.br_nominal) {
157 		if (id->base.br_nominal != 255) {
158 			br_nom = id->base.br_nominal * 100;
159 			br_min = br_nom - id->base.br_nominal * id->ext.br_min;
160 			br_max = br_nom + id->base.br_nominal * id->ext.br_max;
161 		} else if (id->ext.br_max) {
162 			br_nom = 250 * id->ext.br_max;
163 			br_max = br_nom + br_nom * id->ext.br_min / 100;
164 			br_min = br_nom - br_nom * id->ext.br_min / 100;
165 		}
166 
167 		/* When using passive cables, in case neither BR,min nor BR,max
168 		 * are specified, set br_min to 0 as the nominal value is then
169 		 * used as the maximum.
170 		 */
171 		if (br_min == br_max && id->base.sfp_ct_passive)
172 			br_min = 0;
173 	}
174 
175 	/* Set ethtool support from the compliance fields. */
176 	if (id->base.e10g_base_sr) {
177 		phylink_set(modes, 10000baseSR_Full);
178 		__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
179 	}
180 	if (id->base.e10g_base_lr) {
181 		phylink_set(modes, 10000baseLR_Full);
182 		__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
183 	}
184 	if (id->base.e10g_base_lrm) {
185 		phylink_set(modes, 10000baseLRM_Full);
186 		__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
187 	}
188 	if (id->base.e10g_base_er) {
189 		phylink_set(modes, 10000baseER_Full);
190 		__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
191 	}
192 	if (id->base.e1000_base_sx ||
193 	    id->base.e1000_base_lx ||
194 	    id->base.e1000_base_cx) {
195 		phylink_set(modes, 1000baseX_Full);
196 		__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
197 	}
198 	if (id->base.e1000_base_t) {
199 		phylink_set(modes, 1000baseT_Half);
200 		phylink_set(modes, 1000baseT_Full);
201 		__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
202 		__set_bit(PHY_INTERFACE_MODE_SGMII, interfaces);
203 	}
204 
205 	/* 1000Base-PX or 1000Base-BX10 */
206 	if ((id->base.e_base_px || id->base.e_base_bx10) &&
207 	    br_min <= 1300 && br_max >= 1200) {
208 		phylink_set(modes, 1000baseX_Full);
209 		__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
210 	}
211 
212 	/* 100Base-FX, 100Base-LX, 100Base-PX, 100Base-BX10 */
213 	if (id->base.e100_base_fx || id->base.e100_base_lx) {
214 		phylink_set(modes, 100baseFX_Full);
215 		__set_bit(PHY_INTERFACE_MODE_100BASEX, interfaces);
216 	}
217 	if ((id->base.e_base_px || id->base.e_base_bx10) && br_nom == 100) {
218 		phylink_set(modes, 100baseFX_Full);
219 		__set_bit(PHY_INTERFACE_MODE_100BASEX, interfaces);
220 	}
221 
222 	/* For active or passive cables, select the link modes
223 	 * based on the bit rates and the cable compliance bytes.
224 	 */
225 	if ((id->base.sfp_ct_passive || id->base.sfp_ct_active) && br_nom) {
226 		/* This may look odd, but some manufacturers use 12000MBd */
227 		if (br_min <= 12000 && br_max >= 10300) {
228 			phylink_set(modes, 10000baseCR_Full);
229 			__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
230 		}
231 		if (br_min <= 3200 && br_max >= 3100) {
232 			phylink_set(modes, 2500baseX_Full);
233 			__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
234 		}
235 		if (br_min <= 1300 && br_max >= 1200) {
236 			phylink_set(modes, 1000baseX_Full);
237 			__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
238 		}
239 	}
240 	if (id->base.sfp_ct_passive) {
241 		if (id->base.passive.sff8431_app_e) {
242 			phylink_set(modes, 10000baseCR_Full);
243 			__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
244 		}
245 	}
246 	if (id->base.sfp_ct_active) {
247 		if (id->base.active.sff8431_app_e ||
248 		    id->base.active.sff8431_lim) {
249 			phylink_set(modes, 10000baseCR_Full);
250 			__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
251 		}
252 	}
253 
254 	switch (id->base.extended_cc) {
255 	case SFF8024_ECC_UNSPEC:
256 		break;
257 	case SFF8024_ECC_100G_25GAUI_C2M_AOC:
258 		if (br_min <= 28000 && br_max >= 25000) {
259 			/* 25GBASE-R, possibly with FEC */
260 			__set_bit(PHY_INTERFACE_MODE_25GBASER, interfaces);
261 			/* There is currently no link mode for 25000base
262 			 * with unspecified range, reuse SR.
263 			 */
264 			phylink_set(modes, 25000baseSR_Full);
265 		}
266 		break;
267 	case SFF8024_ECC_100GBASE_SR4_25GBASE_SR:
268 		phylink_set(modes, 100000baseSR4_Full);
269 		phylink_set(modes, 25000baseSR_Full);
270 		__set_bit(PHY_INTERFACE_MODE_25GBASER, interfaces);
271 		break;
272 	case SFF8024_ECC_100GBASE_LR4_25GBASE_LR:
273 	case SFF8024_ECC_100GBASE_ER4_25GBASE_ER:
274 		phylink_set(modes, 100000baseLR4_ER4_Full);
275 		break;
276 	case SFF8024_ECC_100GBASE_CR4:
277 		phylink_set(modes, 100000baseCR4_Full);
278 		fallthrough;
279 	case SFF8024_ECC_25GBASE_CR_S:
280 	case SFF8024_ECC_25GBASE_CR_N:
281 		phylink_set(modes, 25000baseCR_Full);
282 		__set_bit(PHY_INTERFACE_MODE_25GBASER, interfaces);
283 		break;
284 	case SFF8024_ECC_10GBASE_T_SFI:
285 	case SFF8024_ECC_10GBASE_T_SR:
286 		phylink_set(modes, 10000baseT_Full);
287 		__set_bit(PHY_INTERFACE_MODE_10GBASER, interfaces);
288 		break;
289 	case SFF8024_ECC_5GBASE_T:
290 		phylink_set(modes, 5000baseT_Full);
291 		__set_bit(PHY_INTERFACE_MODE_5GBASER, interfaces);
292 		break;
293 	case SFF8024_ECC_2_5GBASE_T:
294 		phylink_set(modes, 2500baseT_Full);
295 		__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
296 		break;
297 	default:
298 		dev_warn(bus->sfp_dev,
299 			 "Unknown/unsupported extended compliance code: 0x%02x\n",
300 			 id->base.extended_cc);
301 		break;
302 	}
303 
304 	/* For fibre channel SFP, derive possible BaseX modes */
305 	if (id->base.fc_speed_100 ||
306 	    id->base.fc_speed_200 ||
307 	    id->base.fc_speed_400) {
308 		if (id->base.br_nominal >= 31) {
309 			phylink_set(modes, 2500baseX_Full);
310 			__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
311 		}
312 		if (id->base.br_nominal >= 12) {
313 			phylink_set(modes, 1000baseX_Full);
314 			__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
315 		}
316 	}
317 
318 	/* If we haven't discovered any modes that this module supports, try
319 	 * the bitrate to determine supported modes. Some BiDi modules (eg,
320 	 * 1310nm/1550nm) are not 1000BASE-BX compliant due to the differing
321 	 * wavelengths, so do not set any transceiver bits.
322 	 *
323 	 * Do the same for modules supporting 2500BASE-X. Note that some
324 	 * modules use 2500Mbaud rather than 3100 or 3200Mbaud for
325 	 * 2500BASE-X, so we allow some slack here.
326 	 */
327 	if (linkmode_empty(modes) && br_nom) {
328 		if (br_min <= 1300 && br_max >= 1200) {
329 			phylink_set(modes, 1000baseX_Full);
330 			__set_bit(PHY_INTERFACE_MODE_1000BASEX, interfaces);
331 		}
332 		if (br_min <= 3200 && br_max >= 2500) {
333 			phylink_set(modes, 2500baseX_Full);
334 			__set_bit(PHY_INTERFACE_MODE_2500BASEX, interfaces);
335 		}
336 	}
337 
338 	phylink_set(modes, Autoneg);
339 	phylink_set(modes, Pause);
340 	phylink_set(modes, Asym_Pause);
341 
342 	if (bus->sfp_quirk && bus->sfp_quirk->modes)
343 		bus->sfp_quirk->modes(id, modes, interfaces);
344 
345 	linkmode_or(support, support, modes);
346 }
347 EXPORT_SYMBOL_GPL(sfp_parse_support);
348 
349 /**
350  * sfp_select_interface() - Select appropriate phy_interface_t mode
351  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
352  * @link_modes: ethtool link modes mask
353  *
354  * Derive the phy_interface_t mode for the SFP module from the link
355  * modes mask.
356  */
357 phy_interface_t sfp_select_interface(struct sfp_bus *bus,
358 				     const unsigned long *link_modes)
359 {
360 	if (phylink_test(link_modes, 25000baseCR_Full) ||
361 	    phylink_test(link_modes, 25000baseKR_Full) ||
362 	    phylink_test(link_modes, 25000baseSR_Full))
363 		return PHY_INTERFACE_MODE_25GBASER;
364 
365 	if (phylink_test(link_modes, 10000baseCR_Full) ||
366 	    phylink_test(link_modes, 10000baseSR_Full) ||
367 	    phylink_test(link_modes, 10000baseLR_Full) ||
368 	    phylink_test(link_modes, 10000baseLRM_Full) ||
369 	    phylink_test(link_modes, 10000baseER_Full) ||
370 	    phylink_test(link_modes, 10000baseT_Full))
371 		return PHY_INTERFACE_MODE_10GBASER;
372 
373 	if (phylink_test(link_modes, 5000baseT_Full))
374 		return PHY_INTERFACE_MODE_5GBASER;
375 
376 	if (phylink_test(link_modes, 2500baseX_Full) ||
377 	    phylink_test(link_modes, 2500baseT_Full))
378 		return PHY_INTERFACE_MODE_2500BASEX;
379 
380 	if (phylink_test(link_modes, 1000baseT_Half) ||
381 	    phylink_test(link_modes, 1000baseT_Full))
382 		return PHY_INTERFACE_MODE_SGMII;
383 
384 	if (phylink_test(link_modes, 1000baseX_Full))
385 		return PHY_INTERFACE_MODE_1000BASEX;
386 
387 	if (phylink_test(link_modes, 100baseFX_Full))
388 		return PHY_INTERFACE_MODE_100BASEX;
389 
390 	dev_warn(bus->sfp_dev, "Unable to ascertain link mode\n");
391 
392 	return PHY_INTERFACE_MODE_NA;
393 }
394 EXPORT_SYMBOL_GPL(sfp_select_interface);
395 
396 static LIST_HEAD(sfp_buses);
397 static DEFINE_MUTEX(sfp_mutex);
398 
399 static const struct sfp_upstream_ops *sfp_get_upstream_ops(struct sfp_bus *bus)
400 {
401 	return bus->registered ? bus->upstream_ops : NULL;
402 }
403 
404 static struct sfp_bus *sfp_bus_get(const struct fwnode_handle *fwnode)
405 {
406 	struct sfp_bus *sfp, *new, *found = NULL;
407 
408 	new = kzalloc(sizeof(*new), GFP_KERNEL);
409 
410 	mutex_lock(&sfp_mutex);
411 
412 	list_for_each_entry(sfp, &sfp_buses, node) {
413 		if (sfp->fwnode == fwnode) {
414 			kref_get(&sfp->kref);
415 			found = sfp;
416 			break;
417 		}
418 	}
419 
420 	if (!found && new) {
421 		kref_init(&new->kref);
422 		new->fwnode = fwnode;
423 		list_add(&new->node, &sfp_buses);
424 		found = new;
425 		new = NULL;
426 	}
427 
428 	mutex_unlock(&sfp_mutex);
429 
430 	kfree(new);
431 
432 	return found;
433 }
434 
435 static void sfp_bus_release(struct kref *kref)
436 {
437 	struct sfp_bus *bus = container_of(kref, struct sfp_bus, kref);
438 
439 	list_del(&bus->node);
440 	mutex_unlock(&sfp_mutex);
441 	kfree(bus);
442 }
443 
444 /**
445  * sfp_bus_put() - put a reference on the &struct sfp_bus
446  * @bus: the &struct sfp_bus found via sfp_bus_find_fwnode()
447  *
448  * Put a reference on the &struct sfp_bus and free the underlying structure
449  * if this was the last reference.
450  */
451 void sfp_bus_put(struct sfp_bus *bus)
452 {
453 	if (bus)
454 		kref_put_mutex(&bus->kref, sfp_bus_release, &sfp_mutex);
455 }
456 EXPORT_SYMBOL_GPL(sfp_bus_put);
457 
458 static int sfp_register_bus(struct sfp_bus *bus)
459 {
460 	const struct sfp_upstream_ops *ops = bus->upstream_ops;
461 	int ret;
462 
463 	if (ops) {
464 		if (ops->link_down)
465 			ops->link_down(bus->upstream);
466 		if (ops->connect_phy && bus->phydev) {
467 			ret = ops->connect_phy(bus->upstream, bus->phydev);
468 			if (ret)
469 				return ret;
470 		}
471 	}
472 	bus->registered = true;
473 	bus->socket_ops->attach(bus->sfp);
474 	if (bus->started)
475 		bus->socket_ops->start(bus->sfp);
476 	bus->upstream_ops->attach(bus->upstream, bus);
477 	return 0;
478 }
479 
480 static void sfp_unregister_bus(struct sfp_bus *bus)
481 {
482 	const struct sfp_upstream_ops *ops = bus->upstream_ops;
483 
484 	if (bus->registered) {
485 		bus->upstream_ops->detach(bus->upstream, bus);
486 		if (bus->started)
487 			bus->socket_ops->stop(bus->sfp);
488 		bus->socket_ops->detach(bus->sfp);
489 		if (bus->phydev && ops && ops->disconnect_phy)
490 			ops->disconnect_phy(bus->upstream);
491 	}
492 	bus->registered = false;
493 }
494 
495 /**
496  * sfp_get_module_info() - Get the ethtool_modinfo for a SFP module
497  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
498  * @modinfo: a &struct ethtool_modinfo
499  *
500  * Fill in the type and eeprom_len parameters in @modinfo for a module on
501  * the sfp bus specified by @bus.
502  *
503  * Returns 0 on success or a negative errno number.
504  */
505 int sfp_get_module_info(struct sfp_bus *bus, struct ethtool_modinfo *modinfo)
506 {
507 	return bus->socket_ops->module_info(bus->sfp, modinfo);
508 }
509 EXPORT_SYMBOL_GPL(sfp_get_module_info);
510 
511 /**
512  * sfp_get_module_eeprom() - Read the SFP module EEPROM
513  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
514  * @ee: a &struct ethtool_eeprom
515  * @data: buffer to contain the EEPROM data (must be at least @ee->len bytes)
516  *
517  * Read the EEPROM as specified by the supplied @ee. See the documentation
518  * for &struct ethtool_eeprom for the region to be read.
519  *
520  * Returns 0 on success or a negative errno number.
521  */
522 int sfp_get_module_eeprom(struct sfp_bus *bus, struct ethtool_eeprom *ee,
523 			  u8 *data)
524 {
525 	return bus->socket_ops->module_eeprom(bus->sfp, ee, data);
526 }
527 EXPORT_SYMBOL_GPL(sfp_get_module_eeprom);
528 
529 /**
530  * sfp_get_module_eeprom_by_page() - Read a page from the SFP module EEPROM
531  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
532  * @page: a &struct ethtool_module_eeprom
533  * @extack: extack for reporting problems
534  *
535  * Read an EEPROM page as specified by the supplied @page. See the
536  * documentation for &struct ethtool_module_eeprom for the page to be read.
537  *
538  * Returns 0 on success or a negative errno number. More error
539  * information might be provided via extack
540  */
541 int sfp_get_module_eeprom_by_page(struct sfp_bus *bus,
542 				  const struct ethtool_module_eeprom *page,
543 				  struct netlink_ext_ack *extack)
544 {
545 	return bus->socket_ops->module_eeprom_by_page(bus->sfp, page, extack);
546 }
547 EXPORT_SYMBOL_GPL(sfp_get_module_eeprom_by_page);
548 
549 /**
550  * sfp_upstream_start() - Inform the SFP that the network device is up
551  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
552  *
553  * Inform the SFP socket that the network device is now up, so that the
554  * module can be enabled by allowing TX_DISABLE to be deasserted. This
555  * should be called from the network device driver's &struct net_device_ops
556  * ndo_open() method.
557  */
558 void sfp_upstream_start(struct sfp_bus *bus)
559 {
560 	if (bus->registered)
561 		bus->socket_ops->start(bus->sfp);
562 	bus->started = true;
563 }
564 EXPORT_SYMBOL_GPL(sfp_upstream_start);
565 
566 /**
567  * sfp_upstream_stop() - Inform the SFP that the network device is down
568  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
569  *
570  * Inform the SFP socket that the network device is now up, so that the
571  * module can be disabled by asserting TX_DISABLE, disabling the laser
572  * in optical modules. This should be called from the network device
573  * driver's &struct net_device_ops ndo_stop() method.
574  */
575 void sfp_upstream_stop(struct sfp_bus *bus)
576 {
577 	if (bus->registered)
578 		bus->socket_ops->stop(bus->sfp);
579 	bus->started = false;
580 }
581 EXPORT_SYMBOL_GPL(sfp_upstream_stop);
582 
583 static void sfp_upstream_clear(struct sfp_bus *bus)
584 {
585 	bus->upstream_ops = NULL;
586 	bus->upstream = NULL;
587 }
588 
589 /**
590  * sfp_upstream_set_signal_rate() - set data signalling rate
591  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
592  * @rate_kbd: signalling rate in units of 1000 baud
593  *
594  * Configure the rate select settings on the SFP module for the signalling
595  * rate (not the same as the data rate).
596  *
597  * Locks that may be held:
598  *  Phylink's state_mutex
599  *  rtnl lock
600  *  SFP's sm_mutex
601  */
602 void sfp_upstream_set_signal_rate(struct sfp_bus *bus, unsigned int rate_kbd)
603 {
604 	if (bus->registered)
605 		bus->socket_ops->set_signal_rate(bus->sfp, rate_kbd);
606 }
607 EXPORT_SYMBOL_GPL(sfp_upstream_set_signal_rate);
608 
609 /**
610  * sfp_bus_find_fwnode() - parse and locate the SFP bus from fwnode
611  * @fwnode: firmware node for the parent device (MAC or PHY)
612  *
613  * Parse the parent device's firmware node for a SFP bus, and locate
614  * the sfp_bus structure, incrementing its reference count.  This must
615  * be put via sfp_bus_put() when done.
616  *
617  * Returns:
618  *	- on success, a pointer to the sfp_bus structure,
619  *	- %NULL if no SFP is specified,
620  *	- on failure, an error pointer value:
621  *
622  *	- corresponding to the errors detailed for
623  *	  fwnode_property_get_reference_args().
624  *	- %-ENOMEM if we failed to allocate the bus.
625  *	- an error from the upstream's connect_phy() method.
626  */
627 struct sfp_bus *sfp_bus_find_fwnode(const struct fwnode_handle *fwnode)
628 {
629 	struct fwnode_reference_args ref;
630 	struct sfp_bus *bus;
631 	int ret;
632 
633 	ret = fwnode_property_get_reference_args(fwnode, "sfp", NULL,
634 						 0, 0, &ref);
635 	if (ret == -ENOENT)
636 		return NULL;
637 	else if (ret < 0)
638 		return ERR_PTR(ret);
639 
640 	if (!fwnode_device_is_available(ref.fwnode)) {
641 		fwnode_handle_put(ref.fwnode);
642 		return NULL;
643 	}
644 
645 	bus = sfp_bus_get(ref.fwnode);
646 	fwnode_handle_put(ref.fwnode);
647 	if (!bus)
648 		return ERR_PTR(-ENOMEM);
649 
650 	return bus;
651 }
652 EXPORT_SYMBOL_GPL(sfp_bus_find_fwnode);
653 
654 /**
655  * sfp_bus_add_upstream() - parse and register the neighbouring device
656  * @bus: the &struct sfp_bus found via sfp_bus_find_fwnode()
657  * @upstream: the upstream private data
658  * @ops: the upstream's &struct sfp_upstream_ops
659  *
660  * Add upstream driver for the SFP bus, and if the bus is complete, register
661  * the SFP bus using sfp_register_upstream().  This takes a reference on the
662  * bus, so it is safe to put the bus after this call.
663  *
664  * Returns:
665  *	- on success, a pointer to the sfp_bus structure,
666  *	- %NULL if no SFP is specified,
667  *	- on failure, an error pointer value:
668  *
669  *	- corresponding to the errors detailed for
670  *	  fwnode_property_get_reference_args().
671  *	- %-ENOMEM if we failed to allocate the bus.
672  *	- an error from the upstream's connect_phy() method.
673  */
674 int sfp_bus_add_upstream(struct sfp_bus *bus, void *upstream,
675 			 const struct sfp_upstream_ops *ops)
676 {
677 	int ret;
678 
679 	/* If no bus, return success */
680 	if (!bus)
681 		return 0;
682 
683 	rtnl_lock();
684 	kref_get(&bus->kref);
685 	bus->upstream_ops = ops;
686 	bus->upstream = upstream;
687 
688 	if (bus->sfp) {
689 		ret = sfp_register_bus(bus);
690 		if (ret)
691 			sfp_upstream_clear(bus);
692 	} else {
693 		ret = 0;
694 	}
695 	rtnl_unlock();
696 
697 	if (ret)
698 		sfp_bus_put(bus);
699 
700 	return ret;
701 }
702 EXPORT_SYMBOL_GPL(sfp_bus_add_upstream);
703 
704 /**
705  * sfp_bus_del_upstream() - Delete a sfp bus
706  * @bus: a pointer to the &struct sfp_bus structure for the sfp module
707  *
708  * Delete a previously registered upstream connection for the SFP
709  * module. @bus should have been added by sfp_bus_add_upstream().
710  */
711 void sfp_bus_del_upstream(struct sfp_bus *bus)
712 {
713 	if (bus) {
714 		rtnl_lock();
715 		if (bus->sfp)
716 			sfp_unregister_bus(bus);
717 		sfp_upstream_clear(bus);
718 		rtnl_unlock();
719 
720 		sfp_bus_put(bus);
721 	}
722 }
723 EXPORT_SYMBOL_GPL(sfp_bus_del_upstream);
724 
725 /* Socket driver entry points */
726 int sfp_add_phy(struct sfp_bus *bus, struct phy_device *phydev)
727 {
728 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
729 	int ret = 0;
730 
731 	if (ops && ops->connect_phy)
732 		ret = ops->connect_phy(bus->upstream, phydev);
733 
734 	if (ret == 0)
735 		bus->phydev = phydev;
736 
737 	return ret;
738 }
739 EXPORT_SYMBOL_GPL(sfp_add_phy);
740 
741 void sfp_remove_phy(struct sfp_bus *bus)
742 {
743 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
744 
745 	if (ops && ops->disconnect_phy)
746 		ops->disconnect_phy(bus->upstream);
747 	bus->phydev = NULL;
748 }
749 EXPORT_SYMBOL_GPL(sfp_remove_phy);
750 
751 void sfp_link_up(struct sfp_bus *bus)
752 {
753 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
754 
755 	if (ops && ops->link_up)
756 		ops->link_up(bus->upstream);
757 }
758 EXPORT_SYMBOL_GPL(sfp_link_up);
759 
760 void sfp_link_down(struct sfp_bus *bus)
761 {
762 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
763 
764 	if (ops && ops->link_down)
765 		ops->link_down(bus->upstream);
766 }
767 EXPORT_SYMBOL_GPL(sfp_link_down);
768 
769 int sfp_module_insert(struct sfp_bus *bus, const struct sfp_eeprom_id *id,
770 		      const struct sfp_quirk *quirk)
771 {
772 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
773 	int ret = 0;
774 
775 	bus->sfp_quirk = quirk;
776 
777 	if (ops && ops->module_insert)
778 		ret = ops->module_insert(bus->upstream, id);
779 
780 	return ret;
781 }
782 EXPORT_SYMBOL_GPL(sfp_module_insert);
783 
784 void sfp_module_remove(struct sfp_bus *bus)
785 {
786 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
787 
788 	if (ops && ops->module_remove)
789 		ops->module_remove(bus->upstream);
790 
791 	bus->sfp_quirk = NULL;
792 }
793 EXPORT_SYMBOL_GPL(sfp_module_remove);
794 
795 int sfp_module_start(struct sfp_bus *bus)
796 {
797 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
798 	int ret = 0;
799 
800 	if (ops && ops->module_start)
801 		ret = ops->module_start(bus->upstream);
802 
803 	return ret;
804 }
805 EXPORT_SYMBOL_GPL(sfp_module_start);
806 
807 void sfp_module_stop(struct sfp_bus *bus)
808 {
809 	const struct sfp_upstream_ops *ops = sfp_get_upstream_ops(bus);
810 
811 	if (ops && ops->module_stop)
812 		ops->module_stop(bus->upstream);
813 }
814 EXPORT_SYMBOL_GPL(sfp_module_stop);
815 
816 static void sfp_socket_clear(struct sfp_bus *bus)
817 {
818 	bus->sfp_dev = NULL;
819 	bus->sfp = NULL;
820 	bus->socket_ops = NULL;
821 }
822 
823 struct sfp_bus *sfp_register_socket(struct device *dev, struct sfp *sfp,
824 				    const struct sfp_socket_ops *ops)
825 {
826 	struct sfp_bus *bus = sfp_bus_get(dev->fwnode);
827 	int ret = 0;
828 
829 	if (bus) {
830 		rtnl_lock();
831 		bus->sfp_dev = dev;
832 		bus->sfp = sfp;
833 		bus->socket_ops = ops;
834 
835 		if (bus->upstream_ops) {
836 			ret = sfp_register_bus(bus);
837 			if (ret)
838 				sfp_socket_clear(bus);
839 		}
840 		rtnl_unlock();
841 	}
842 
843 	if (ret) {
844 		sfp_bus_put(bus);
845 		bus = NULL;
846 	}
847 
848 	return bus;
849 }
850 EXPORT_SYMBOL_GPL(sfp_register_socket);
851 
852 void sfp_unregister_socket(struct sfp_bus *bus)
853 {
854 	rtnl_lock();
855 	if (bus->upstream_ops)
856 		sfp_unregister_bus(bus);
857 	sfp_socket_clear(bus);
858 	rtnl_unlock();
859 
860 	sfp_bus_put(bus);
861 }
862 EXPORT_SYMBOL_GPL(sfp_unregister_socket);
863