xref: /openbmc/linux/drivers/net/phy/phy-core.c (revision 287dcc2b)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Core PHY library, taken from phy.c
4  */
5 #include <linux/export.h>
6 #include <linux/phy.h>
7 #include <linux/of.h>
8 
9 /**
10  * phy_speed_to_str - Return a string representing the PHY link speed
11  *
12  * @speed: Speed of the link
13  */
14 const char *phy_speed_to_str(int speed)
15 {
16 	BUILD_BUG_ON_MSG(__ETHTOOL_LINK_MODE_MASK_NBITS != 102,
17 		"Enum ethtool_link_mode_bit_indices and phylib are out of sync. "
18 		"If a speed or mode has been added please update phy_speed_to_str "
19 		"and the PHY settings array.\n");
20 
21 	switch (speed) {
22 	case SPEED_10:
23 		return "10Mbps";
24 	case SPEED_100:
25 		return "100Mbps";
26 	case SPEED_1000:
27 		return "1Gbps";
28 	case SPEED_2500:
29 		return "2.5Gbps";
30 	case SPEED_5000:
31 		return "5Gbps";
32 	case SPEED_10000:
33 		return "10Gbps";
34 	case SPEED_14000:
35 		return "14Gbps";
36 	case SPEED_20000:
37 		return "20Gbps";
38 	case SPEED_25000:
39 		return "25Gbps";
40 	case SPEED_40000:
41 		return "40Gbps";
42 	case SPEED_50000:
43 		return "50Gbps";
44 	case SPEED_56000:
45 		return "56Gbps";
46 	case SPEED_100000:
47 		return "100Gbps";
48 	case SPEED_200000:
49 		return "200Gbps";
50 	case SPEED_400000:
51 		return "400Gbps";
52 	case SPEED_800000:
53 		return "800Gbps";
54 	case SPEED_UNKNOWN:
55 		return "Unknown";
56 	default:
57 		return "Unsupported (update phy-core.c)";
58 	}
59 }
60 EXPORT_SYMBOL_GPL(phy_speed_to_str);
61 
62 /**
63  * phy_duplex_to_str - Return string describing the duplex
64  *
65  * @duplex: Duplex setting to describe
66  */
67 const char *phy_duplex_to_str(unsigned int duplex)
68 {
69 	if (duplex == DUPLEX_HALF)
70 		return "Half";
71 	if (duplex == DUPLEX_FULL)
72 		return "Full";
73 	if (duplex == DUPLEX_UNKNOWN)
74 		return "Unknown";
75 	return "Unsupported (update phy-core.c)";
76 }
77 EXPORT_SYMBOL_GPL(phy_duplex_to_str);
78 
79 /**
80  * phy_rate_matching_to_str - Return a string describing the rate matching
81  *
82  * @rate_matching: Type of rate matching to describe
83  */
84 const char *phy_rate_matching_to_str(int rate_matching)
85 {
86 	switch (rate_matching) {
87 	case RATE_MATCH_NONE:
88 		return "none";
89 	case RATE_MATCH_PAUSE:
90 		return "pause";
91 	case RATE_MATCH_CRS:
92 		return "crs";
93 	case RATE_MATCH_OPEN_LOOP:
94 		return "open-loop";
95 	}
96 	return "Unsupported (update phy-core.c)";
97 }
98 EXPORT_SYMBOL_GPL(phy_rate_matching_to_str);
99 
100 /**
101  * phy_interface_num_ports - Return the number of links that can be carried by
102  *			     a given MAC-PHY physical link. Returns 0 if this is
103  *			     unknown, the number of links else.
104  *
105  * @interface: The interface mode we want to get the number of ports
106  */
107 int phy_interface_num_ports(phy_interface_t interface)
108 {
109 	switch (interface) {
110 	case PHY_INTERFACE_MODE_NA:
111 		return 0;
112 	case PHY_INTERFACE_MODE_INTERNAL:
113 	case PHY_INTERFACE_MODE_MII:
114 	case PHY_INTERFACE_MODE_GMII:
115 	case PHY_INTERFACE_MODE_TBI:
116 	case PHY_INTERFACE_MODE_REVMII:
117 	case PHY_INTERFACE_MODE_RMII:
118 	case PHY_INTERFACE_MODE_REVRMII:
119 	case PHY_INTERFACE_MODE_RGMII:
120 	case PHY_INTERFACE_MODE_RGMII_ID:
121 	case PHY_INTERFACE_MODE_RGMII_RXID:
122 	case PHY_INTERFACE_MODE_RGMII_TXID:
123 	case PHY_INTERFACE_MODE_RTBI:
124 	case PHY_INTERFACE_MODE_XGMII:
125 	case PHY_INTERFACE_MODE_XLGMII:
126 	case PHY_INTERFACE_MODE_MOCA:
127 	case PHY_INTERFACE_MODE_TRGMII:
128 	case PHY_INTERFACE_MODE_USXGMII:
129 	case PHY_INTERFACE_MODE_SGMII:
130 	case PHY_INTERFACE_MODE_SMII:
131 	case PHY_INTERFACE_MODE_1000BASEX:
132 	case PHY_INTERFACE_MODE_2500BASEX:
133 	case PHY_INTERFACE_MODE_5GBASER:
134 	case PHY_INTERFACE_MODE_10GBASER:
135 	case PHY_INTERFACE_MODE_25GBASER:
136 	case PHY_INTERFACE_MODE_10GKR:
137 	case PHY_INTERFACE_MODE_100BASEX:
138 	case PHY_INTERFACE_MODE_RXAUI:
139 	case PHY_INTERFACE_MODE_XAUI:
140 	case PHY_INTERFACE_MODE_1000BASEKX:
141 		return 1;
142 	case PHY_INTERFACE_MODE_QSGMII:
143 	case PHY_INTERFACE_MODE_QUSGMII:
144 		return 4;
145 	case PHY_INTERFACE_MODE_MAX:
146 		WARN_ONCE(1, "PHY_INTERFACE_MODE_MAX isn't a valid interface mode");
147 		return 0;
148 	}
149 	return 0;
150 }
151 EXPORT_SYMBOL_GPL(phy_interface_num_ports);
152 
153 /* A mapping of all SUPPORTED settings to speed/duplex.  This table
154  * must be grouped by speed and sorted in descending match priority
155  * - iow, descending speed.
156  */
157 
158 #define PHY_SETTING(s, d, b) { .speed = SPEED_ ## s, .duplex = DUPLEX_ ## d, \
159 			       .bit = ETHTOOL_LINK_MODE_ ## b ## _BIT}
160 
161 static const struct phy_setting settings[] = {
162 	/* 800G */
163 	PHY_SETTING( 800000, FULL, 800000baseCR8_Full		),
164 	PHY_SETTING( 800000, FULL, 800000baseKR8_Full		),
165 	PHY_SETTING( 800000, FULL, 800000baseDR8_Full		),
166 	PHY_SETTING( 800000, FULL, 800000baseDR8_2_Full		),
167 	PHY_SETTING( 800000, FULL, 800000baseSR8_Full		),
168 	PHY_SETTING( 800000, FULL, 800000baseVR8_Full		),
169 	/* 400G */
170 	PHY_SETTING( 400000, FULL, 400000baseCR8_Full		),
171 	PHY_SETTING( 400000, FULL, 400000baseKR8_Full		),
172 	PHY_SETTING( 400000, FULL, 400000baseLR8_ER8_FR8_Full	),
173 	PHY_SETTING( 400000, FULL, 400000baseDR8_Full		),
174 	PHY_SETTING( 400000, FULL, 400000baseSR8_Full		),
175 	PHY_SETTING( 400000, FULL, 400000baseCR4_Full		),
176 	PHY_SETTING( 400000, FULL, 400000baseKR4_Full		),
177 	PHY_SETTING( 400000, FULL, 400000baseLR4_ER4_FR4_Full	),
178 	PHY_SETTING( 400000, FULL, 400000baseDR4_Full		),
179 	PHY_SETTING( 400000, FULL, 400000baseSR4_Full		),
180 	/* 200G */
181 	PHY_SETTING( 200000, FULL, 200000baseCR4_Full		),
182 	PHY_SETTING( 200000, FULL, 200000baseKR4_Full		),
183 	PHY_SETTING( 200000, FULL, 200000baseLR4_ER4_FR4_Full	),
184 	PHY_SETTING( 200000, FULL, 200000baseDR4_Full		),
185 	PHY_SETTING( 200000, FULL, 200000baseSR4_Full		),
186 	PHY_SETTING( 200000, FULL, 200000baseCR2_Full		),
187 	PHY_SETTING( 200000, FULL, 200000baseKR2_Full		),
188 	PHY_SETTING( 200000, FULL, 200000baseLR2_ER2_FR2_Full	),
189 	PHY_SETTING( 200000, FULL, 200000baseDR2_Full		),
190 	PHY_SETTING( 200000, FULL, 200000baseSR2_Full		),
191 	/* 100G */
192 	PHY_SETTING( 100000, FULL, 100000baseCR4_Full		),
193 	PHY_SETTING( 100000, FULL, 100000baseKR4_Full		),
194 	PHY_SETTING( 100000, FULL, 100000baseLR4_ER4_Full	),
195 	PHY_SETTING( 100000, FULL, 100000baseSR4_Full		),
196 	PHY_SETTING( 100000, FULL, 100000baseCR2_Full		),
197 	PHY_SETTING( 100000, FULL, 100000baseKR2_Full		),
198 	PHY_SETTING( 100000, FULL, 100000baseLR2_ER2_FR2_Full	),
199 	PHY_SETTING( 100000, FULL, 100000baseDR2_Full		),
200 	PHY_SETTING( 100000, FULL, 100000baseSR2_Full		),
201 	PHY_SETTING( 100000, FULL, 100000baseCR_Full		),
202 	PHY_SETTING( 100000, FULL, 100000baseKR_Full		),
203 	PHY_SETTING( 100000, FULL, 100000baseLR_ER_FR_Full	),
204 	PHY_SETTING( 100000, FULL, 100000baseDR_Full		),
205 	PHY_SETTING( 100000, FULL, 100000baseSR_Full		),
206 	/* 56G */
207 	PHY_SETTING(  56000, FULL,  56000baseCR4_Full	  	),
208 	PHY_SETTING(  56000, FULL,  56000baseKR4_Full	  	),
209 	PHY_SETTING(  56000, FULL,  56000baseLR4_Full	  	),
210 	PHY_SETTING(  56000, FULL,  56000baseSR4_Full	  	),
211 	/* 50G */
212 	PHY_SETTING(  50000, FULL,  50000baseCR2_Full		),
213 	PHY_SETTING(  50000, FULL,  50000baseKR2_Full		),
214 	PHY_SETTING(  50000, FULL,  50000baseSR2_Full		),
215 	PHY_SETTING(  50000, FULL,  50000baseCR_Full		),
216 	PHY_SETTING(  50000, FULL,  50000baseKR_Full		),
217 	PHY_SETTING(  50000, FULL,  50000baseLR_ER_FR_Full	),
218 	PHY_SETTING(  50000, FULL,  50000baseDR_Full		),
219 	PHY_SETTING(  50000, FULL,  50000baseSR_Full		),
220 	/* 40G */
221 	PHY_SETTING(  40000, FULL,  40000baseCR4_Full		),
222 	PHY_SETTING(  40000, FULL,  40000baseKR4_Full		),
223 	PHY_SETTING(  40000, FULL,  40000baseLR4_Full		),
224 	PHY_SETTING(  40000, FULL,  40000baseSR4_Full		),
225 	/* 25G */
226 	PHY_SETTING(  25000, FULL,  25000baseCR_Full		),
227 	PHY_SETTING(  25000, FULL,  25000baseKR_Full		),
228 	PHY_SETTING(  25000, FULL,  25000baseSR_Full		),
229 	/* 20G */
230 	PHY_SETTING(  20000, FULL,  20000baseKR2_Full		),
231 	PHY_SETTING(  20000, FULL,  20000baseMLD2_Full		),
232 	/* 10G */
233 	PHY_SETTING(  10000, FULL,  10000baseCR_Full		),
234 	PHY_SETTING(  10000, FULL,  10000baseER_Full		),
235 	PHY_SETTING(  10000, FULL,  10000baseKR_Full		),
236 	PHY_SETTING(  10000, FULL,  10000baseKX4_Full		),
237 	PHY_SETTING(  10000, FULL,  10000baseLR_Full		),
238 	PHY_SETTING(  10000, FULL,  10000baseLRM_Full		),
239 	PHY_SETTING(  10000, FULL,  10000baseR_FEC		),
240 	PHY_SETTING(  10000, FULL,  10000baseSR_Full		),
241 	PHY_SETTING(  10000, FULL,  10000baseT_Full		),
242 	/* 5G */
243 	PHY_SETTING(   5000, FULL,   5000baseT_Full		),
244 	/* 2.5G */
245 	PHY_SETTING(   2500, FULL,   2500baseT_Full		),
246 	PHY_SETTING(   2500, FULL,   2500baseX_Full		),
247 	/* 1G */
248 	PHY_SETTING(   1000, FULL,   1000baseT_Full		),
249 	PHY_SETTING(   1000, HALF,   1000baseT_Half		),
250 	PHY_SETTING(   1000, FULL,   1000baseT1_Full		),
251 	PHY_SETTING(   1000, FULL,   1000baseX_Full		),
252 	PHY_SETTING(   1000, FULL,   1000baseKX_Full		),
253 	/* 100M */
254 	PHY_SETTING(    100, FULL,    100baseT_Full		),
255 	PHY_SETTING(    100, FULL,    100baseT1_Full		),
256 	PHY_SETTING(    100, HALF,    100baseT_Half		),
257 	PHY_SETTING(    100, HALF,    100baseFX_Half		),
258 	PHY_SETTING(    100, FULL,    100baseFX_Full		),
259 	/* 10M */
260 	PHY_SETTING(     10, FULL,     10baseT_Full		),
261 	PHY_SETTING(     10, HALF,     10baseT_Half		),
262 	PHY_SETTING(     10, FULL,     10baseT1L_Full		),
263 	PHY_SETTING(     10, FULL,     10baseT1S_Full		),
264 	PHY_SETTING(     10, HALF,     10baseT1S_Half		),
265 	PHY_SETTING(     10, HALF,     10baseT1S_P2MP_Half	),
266 };
267 #undef PHY_SETTING
268 
269 /**
270  * phy_lookup_setting - lookup a PHY setting
271  * @speed: speed to match
272  * @duplex: duplex to match
273  * @mask: allowed link modes
274  * @exact: an exact match is required
275  *
276  * Search the settings array for a setting that matches the speed and
277  * duplex, and which is supported.
278  *
279  * If @exact is unset, either an exact match or %NULL for no match will
280  * be returned.
281  *
282  * If @exact is set, an exact match, the fastest supported setting at
283  * or below the specified speed, the slowest supported setting, or if
284  * they all fail, %NULL will be returned.
285  */
286 const struct phy_setting *
287 phy_lookup_setting(int speed, int duplex, const unsigned long *mask, bool exact)
288 {
289 	const struct phy_setting *p, *match = NULL, *last = NULL;
290 	int i;
291 
292 	for (i = 0, p = settings; i < ARRAY_SIZE(settings); i++, p++) {
293 		if (p->bit < __ETHTOOL_LINK_MODE_MASK_NBITS &&
294 		    test_bit(p->bit, mask)) {
295 			last = p;
296 			if (p->speed == speed && p->duplex == duplex) {
297 				/* Exact match for speed and duplex */
298 				match = p;
299 				break;
300 			} else if (!exact) {
301 				if (!match && p->speed <= speed)
302 					/* Candidate */
303 					match = p;
304 
305 				if (p->speed < speed)
306 					break;
307 			}
308 		}
309 	}
310 
311 	if (!match && !exact)
312 		match = last;
313 
314 	return match;
315 }
316 EXPORT_SYMBOL_GPL(phy_lookup_setting);
317 
318 size_t phy_speeds(unsigned int *speeds, size_t size,
319 		  unsigned long *mask)
320 {
321 	size_t count;
322 	int i;
323 
324 	for (i = 0, count = 0; i < ARRAY_SIZE(settings) && count < size; i++)
325 		if (settings[i].bit < __ETHTOOL_LINK_MODE_MASK_NBITS &&
326 		    test_bit(settings[i].bit, mask) &&
327 		    (count == 0 || speeds[count - 1] != settings[i].speed))
328 			speeds[count++] = settings[i].speed;
329 
330 	return count;
331 }
332 
333 static void __set_linkmode_max_speed(u32 max_speed, unsigned long *addr)
334 {
335 	const struct phy_setting *p;
336 	int i;
337 
338 	for (i = 0, p = settings; i < ARRAY_SIZE(settings); i++, p++) {
339 		if (p->speed > max_speed)
340 			linkmode_clear_bit(p->bit, addr);
341 		else
342 			break;
343 	}
344 }
345 
346 static void __set_phy_supported(struct phy_device *phydev, u32 max_speed)
347 {
348 	__set_linkmode_max_speed(max_speed, phydev->supported);
349 }
350 
351 /**
352  * phy_set_max_speed - Set the maximum speed the PHY should support
353  *
354  * @phydev: The phy_device struct
355  * @max_speed: Maximum speed
356  *
357  * The PHY might be more capable than the MAC. For example a Fast Ethernet
358  * is connected to a 1G PHY. This function allows the MAC to indicate its
359  * maximum speed, and so limit what the PHY will advertise.
360  */
361 void phy_set_max_speed(struct phy_device *phydev, u32 max_speed)
362 {
363 	__set_phy_supported(phydev, max_speed);
364 
365 	phy_advertise_supported(phydev);
366 }
367 EXPORT_SYMBOL(phy_set_max_speed);
368 
369 void of_set_phy_supported(struct phy_device *phydev)
370 {
371 	struct device_node *node = phydev->mdio.dev.of_node;
372 	u32 max_speed;
373 
374 	if (!IS_ENABLED(CONFIG_OF_MDIO))
375 		return;
376 
377 	if (!node)
378 		return;
379 
380 	if (!of_property_read_u32(node, "max-speed", &max_speed))
381 		__set_phy_supported(phydev, max_speed);
382 }
383 
384 void of_set_phy_eee_broken(struct phy_device *phydev)
385 {
386 	struct device_node *node = phydev->mdio.dev.of_node;
387 	u32 broken = 0;
388 
389 	if (!IS_ENABLED(CONFIG_OF_MDIO))
390 		return;
391 
392 	if (!node)
393 		return;
394 
395 	if (of_property_read_bool(node, "eee-broken-100tx"))
396 		broken |= MDIO_EEE_100TX;
397 	if (of_property_read_bool(node, "eee-broken-1000t"))
398 		broken |= MDIO_EEE_1000T;
399 	if (of_property_read_bool(node, "eee-broken-10gt"))
400 		broken |= MDIO_EEE_10GT;
401 	if (of_property_read_bool(node, "eee-broken-1000kx"))
402 		broken |= MDIO_EEE_1000KX;
403 	if (of_property_read_bool(node, "eee-broken-10gkx4"))
404 		broken |= MDIO_EEE_10GKX4;
405 	if (of_property_read_bool(node, "eee-broken-10gkr"))
406 		broken |= MDIO_EEE_10GKR;
407 
408 	phydev->eee_broken_modes = broken;
409 }
410 
411 /**
412  * phy_resolve_aneg_pause - Determine pause autoneg results
413  *
414  * @phydev: The phy_device struct
415  *
416  * Once autoneg has completed the local pause settings can be
417  * resolved.  Determine if pause and asymmetric pause should be used
418  * by the MAC.
419  */
420 
421 void phy_resolve_aneg_pause(struct phy_device *phydev)
422 {
423 	if (phydev->duplex == DUPLEX_FULL) {
424 		phydev->pause = linkmode_test_bit(ETHTOOL_LINK_MODE_Pause_BIT,
425 						  phydev->lp_advertising);
426 		phydev->asym_pause = linkmode_test_bit(
427 			ETHTOOL_LINK_MODE_Asym_Pause_BIT,
428 			phydev->lp_advertising);
429 	}
430 }
431 EXPORT_SYMBOL_GPL(phy_resolve_aneg_pause);
432 
433 /**
434  * phy_resolve_aneg_linkmode - resolve the advertisements into PHY settings
435  * @phydev: The phy_device struct
436  *
437  * Resolve our and the link partner advertisements into their corresponding
438  * speed and duplex. If full duplex was negotiated, extract the pause mode
439  * from the link partner mask.
440  */
441 void phy_resolve_aneg_linkmode(struct phy_device *phydev)
442 {
443 	__ETHTOOL_DECLARE_LINK_MODE_MASK(common);
444 	int i;
445 
446 	linkmode_and(common, phydev->lp_advertising, phydev->advertising);
447 
448 	for (i = 0; i < ARRAY_SIZE(settings); i++)
449 		if (test_bit(settings[i].bit, common)) {
450 			phydev->speed = settings[i].speed;
451 			phydev->duplex = settings[i].duplex;
452 			break;
453 		}
454 
455 	phy_resolve_aneg_pause(phydev);
456 }
457 EXPORT_SYMBOL_GPL(phy_resolve_aneg_linkmode);
458 
459 /**
460  * phy_check_downshift - check whether downshift occurred
461  * @phydev: The phy_device struct
462  *
463  * Check whether a downshift to a lower speed occurred. If this should be the
464  * case warn the user.
465  * Prerequisite for detecting downshift is that PHY driver implements the
466  * read_status callback and sets phydev->speed to the actual link speed.
467  */
468 void phy_check_downshift(struct phy_device *phydev)
469 {
470 	__ETHTOOL_DECLARE_LINK_MODE_MASK(common);
471 	int i, speed = SPEED_UNKNOWN;
472 
473 	phydev->downshifted_rate = 0;
474 
475 	if (phydev->autoneg == AUTONEG_DISABLE ||
476 	    phydev->speed == SPEED_UNKNOWN)
477 		return;
478 
479 	linkmode_and(common, phydev->lp_advertising, phydev->advertising);
480 
481 	for (i = 0; i < ARRAY_SIZE(settings); i++)
482 		if (test_bit(settings[i].bit, common)) {
483 			speed = settings[i].speed;
484 			break;
485 		}
486 
487 	if (speed == SPEED_UNKNOWN || phydev->speed >= speed)
488 		return;
489 
490 	phydev_warn(phydev, "Downshift occurred from negotiated speed %s to actual speed %s, check cabling!\n",
491 		    phy_speed_to_str(speed), phy_speed_to_str(phydev->speed));
492 
493 	phydev->downshifted_rate = 1;
494 }
495 EXPORT_SYMBOL_GPL(phy_check_downshift);
496 
497 static int phy_resolve_min_speed(struct phy_device *phydev, bool fdx_only)
498 {
499 	__ETHTOOL_DECLARE_LINK_MODE_MASK(common);
500 	int i = ARRAY_SIZE(settings);
501 
502 	linkmode_and(common, phydev->lp_advertising, phydev->advertising);
503 
504 	while (--i >= 0) {
505 		if (test_bit(settings[i].bit, common)) {
506 			if (fdx_only && settings[i].duplex != DUPLEX_FULL)
507 				continue;
508 			return settings[i].speed;
509 		}
510 	}
511 
512 	return SPEED_UNKNOWN;
513 }
514 
515 int phy_speed_down_core(struct phy_device *phydev)
516 {
517 	int min_common_speed = phy_resolve_min_speed(phydev, true);
518 
519 	if (min_common_speed == SPEED_UNKNOWN)
520 		return -EINVAL;
521 
522 	__set_linkmode_max_speed(min_common_speed, phydev->advertising);
523 
524 	return 0;
525 }
526 
527 static void mmd_phy_indirect(struct mii_bus *bus, int phy_addr, int devad,
528 			     u16 regnum)
529 {
530 	/* Write the desired MMD Devad */
531 	__mdiobus_write(bus, phy_addr, MII_MMD_CTRL, devad);
532 
533 	/* Write the desired MMD register address */
534 	__mdiobus_write(bus, phy_addr, MII_MMD_DATA, regnum);
535 
536 	/* Select the Function : DATA with no post increment */
537 	__mdiobus_write(bus, phy_addr, MII_MMD_CTRL,
538 			devad | MII_MMD_CTRL_NOINCR);
539 }
540 
541 /**
542  * __phy_read_mmd - Convenience function for reading a register
543  * from an MMD on a given PHY.
544  * @phydev: The phy_device struct
545  * @devad: The MMD to read from (0..31)
546  * @regnum: The register on the MMD to read (0..65535)
547  *
548  * Same rules as for __phy_read();
549  */
550 int __phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
551 {
552 	int val;
553 
554 	if (regnum > (u16)~0 || devad > 32)
555 		return -EINVAL;
556 
557 	if (phydev->drv && phydev->drv->read_mmd) {
558 		val = phydev->drv->read_mmd(phydev, devad, regnum);
559 	} else if (phydev->is_c45) {
560 		val = __mdiobus_c45_read(phydev->mdio.bus, phydev->mdio.addr,
561 					 devad, regnum);
562 	} else {
563 		struct mii_bus *bus = phydev->mdio.bus;
564 		int phy_addr = phydev->mdio.addr;
565 
566 		mmd_phy_indirect(bus, phy_addr, devad, regnum);
567 
568 		/* Read the content of the MMD's selected register */
569 		val = __mdiobus_read(bus, phy_addr, MII_MMD_DATA);
570 	}
571 	return val;
572 }
573 EXPORT_SYMBOL(__phy_read_mmd);
574 
575 /**
576  * phy_read_mmd - Convenience function for reading a register
577  * from an MMD on a given PHY.
578  * @phydev: The phy_device struct
579  * @devad: The MMD to read from
580  * @regnum: The register on the MMD to read
581  *
582  * Same rules as for phy_read();
583  */
584 int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
585 {
586 	int ret;
587 
588 	phy_lock_mdio_bus(phydev);
589 	ret = __phy_read_mmd(phydev, devad, regnum);
590 	phy_unlock_mdio_bus(phydev);
591 
592 	return ret;
593 }
594 EXPORT_SYMBOL(phy_read_mmd);
595 
596 /**
597  * __phy_write_mmd - Convenience function for writing a register
598  * on an MMD on a given PHY.
599  * @phydev: The phy_device struct
600  * @devad: The MMD to read from
601  * @regnum: The register on the MMD to read
602  * @val: value to write to @regnum
603  *
604  * Same rules as for __phy_write();
605  */
606 int __phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
607 {
608 	int ret;
609 
610 	if (regnum > (u16)~0 || devad > 32)
611 		return -EINVAL;
612 
613 	if (phydev->drv && phydev->drv->write_mmd) {
614 		ret = phydev->drv->write_mmd(phydev, devad, regnum, val);
615 	} else if (phydev->is_c45) {
616 		ret = __mdiobus_c45_write(phydev->mdio.bus, phydev->mdio.addr,
617 					  devad, regnum, val);
618 	} else {
619 		struct mii_bus *bus = phydev->mdio.bus;
620 		int phy_addr = phydev->mdio.addr;
621 
622 		mmd_phy_indirect(bus, phy_addr, devad, regnum);
623 
624 		/* Write the data into MMD's selected register */
625 		__mdiobus_write(bus, phy_addr, MII_MMD_DATA, val);
626 
627 		ret = 0;
628 	}
629 	return ret;
630 }
631 EXPORT_SYMBOL(__phy_write_mmd);
632 
633 /**
634  * phy_write_mmd - Convenience function for writing a register
635  * on an MMD on a given PHY.
636  * @phydev: The phy_device struct
637  * @devad: The MMD to read from
638  * @regnum: The register on the MMD to read
639  * @val: value to write to @regnum
640  *
641  * Same rules as for phy_write();
642  */
643 int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
644 {
645 	int ret;
646 
647 	phy_lock_mdio_bus(phydev);
648 	ret = __phy_write_mmd(phydev, devad, regnum, val);
649 	phy_unlock_mdio_bus(phydev);
650 
651 	return ret;
652 }
653 EXPORT_SYMBOL(phy_write_mmd);
654 
655 /**
656  * phy_modify_changed - Function for modifying a PHY register
657  * @phydev: the phy_device struct
658  * @regnum: register number to modify
659  * @mask: bit mask of bits to clear
660  * @set: new value of bits set in mask to write to @regnum
661  *
662  * NOTE: MUST NOT be called from interrupt context,
663  * because the bus read/write functions may wait for an interrupt
664  * to conclude the operation.
665  *
666  * Returns negative errno, 0 if there was no change, and 1 in case of change
667  */
668 int phy_modify_changed(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
669 {
670 	int ret;
671 
672 	phy_lock_mdio_bus(phydev);
673 	ret = __phy_modify_changed(phydev, regnum, mask, set);
674 	phy_unlock_mdio_bus(phydev);
675 
676 	return ret;
677 }
678 EXPORT_SYMBOL_GPL(phy_modify_changed);
679 
680 /**
681  * __phy_modify - Convenience function for modifying a PHY register
682  * @phydev: the phy_device struct
683  * @regnum: register number to modify
684  * @mask: bit mask of bits to clear
685  * @set: new value of bits set in mask to write to @regnum
686  *
687  * NOTE: MUST NOT be called from interrupt context,
688  * because the bus read/write functions may wait for an interrupt
689  * to conclude the operation.
690  */
691 int __phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
692 {
693 	int ret;
694 
695 	ret = __phy_modify_changed(phydev, regnum, mask, set);
696 
697 	return ret < 0 ? ret : 0;
698 }
699 EXPORT_SYMBOL_GPL(__phy_modify);
700 
701 /**
702  * phy_modify - Convenience function for modifying a given PHY register
703  * @phydev: the phy_device struct
704  * @regnum: register number to write
705  * @mask: bit mask of bits to clear
706  * @set: new value of bits set in mask to write to @regnum
707  *
708  * NOTE: MUST NOT be called from interrupt context,
709  * because the bus read/write functions may wait for an interrupt
710  * to conclude the operation.
711  */
712 int phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
713 {
714 	int ret;
715 
716 	phy_lock_mdio_bus(phydev);
717 	ret = __phy_modify(phydev, regnum, mask, set);
718 	phy_unlock_mdio_bus(phydev);
719 
720 	return ret;
721 }
722 EXPORT_SYMBOL_GPL(phy_modify);
723 
724 /**
725  * __phy_modify_mmd_changed - Function for modifying a register on MMD
726  * @phydev: the phy_device struct
727  * @devad: the MMD containing register to modify
728  * @regnum: register number to modify
729  * @mask: bit mask of bits to clear
730  * @set: new value of bits set in mask to write to @regnum
731  *
732  * Unlocked helper function which allows a MMD register to be modified as
733  * new register value = (old register value & ~mask) | set
734  *
735  * Returns negative errno, 0 if there was no change, and 1 in case of change
736  */
737 int __phy_modify_mmd_changed(struct phy_device *phydev, int devad, u32 regnum,
738 			     u16 mask, u16 set)
739 {
740 	int new, ret;
741 
742 	ret = __phy_read_mmd(phydev, devad, regnum);
743 	if (ret < 0)
744 		return ret;
745 
746 	new = (ret & ~mask) | set;
747 	if (new == ret)
748 		return 0;
749 
750 	ret = __phy_write_mmd(phydev, devad, regnum, new);
751 
752 	return ret < 0 ? ret : 1;
753 }
754 EXPORT_SYMBOL_GPL(__phy_modify_mmd_changed);
755 
756 /**
757  * phy_modify_mmd_changed - Function for modifying a register on MMD
758  * @phydev: the phy_device struct
759  * @devad: the MMD containing register to modify
760  * @regnum: register number to modify
761  * @mask: bit mask of bits to clear
762  * @set: new value of bits set in mask to write to @regnum
763  *
764  * NOTE: MUST NOT be called from interrupt context,
765  * because the bus read/write functions may wait for an interrupt
766  * to conclude the operation.
767  *
768  * Returns negative errno, 0 if there was no change, and 1 in case of change
769  */
770 int phy_modify_mmd_changed(struct phy_device *phydev, int devad, u32 regnum,
771 			   u16 mask, u16 set)
772 {
773 	int ret;
774 
775 	phy_lock_mdio_bus(phydev);
776 	ret = __phy_modify_mmd_changed(phydev, devad, regnum, mask, set);
777 	phy_unlock_mdio_bus(phydev);
778 
779 	return ret;
780 }
781 EXPORT_SYMBOL_GPL(phy_modify_mmd_changed);
782 
783 /**
784  * __phy_modify_mmd - Convenience function for modifying a register on MMD
785  * @phydev: the phy_device struct
786  * @devad: the MMD containing register to modify
787  * @regnum: register number to modify
788  * @mask: bit mask of bits to clear
789  * @set: new value of bits set in mask to write to @regnum
790  *
791  * NOTE: MUST NOT be called from interrupt context,
792  * because the bus read/write functions may wait for an interrupt
793  * to conclude the operation.
794  */
795 int __phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
796 		     u16 mask, u16 set)
797 {
798 	int ret;
799 
800 	ret = __phy_modify_mmd_changed(phydev, devad, regnum, mask, set);
801 
802 	return ret < 0 ? ret : 0;
803 }
804 EXPORT_SYMBOL_GPL(__phy_modify_mmd);
805 
806 /**
807  * phy_modify_mmd - Convenience function for modifying a register on MMD
808  * @phydev: the phy_device struct
809  * @devad: the MMD containing register to modify
810  * @regnum: register number to modify
811  * @mask: bit mask of bits to clear
812  * @set: new value of bits set in mask to write to @regnum
813  *
814  * NOTE: MUST NOT be called from interrupt context,
815  * because the bus read/write functions may wait for an interrupt
816  * to conclude the operation.
817  */
818 int phy_modify_mmd(struct phy_device *phydev, int devad, u32 regnum,
819 		   u16 mask, u16 set)
820 {
821 	int ret;
822 
823 	phy_lock_mdio_bus(phydev);
824 	ret = __phy_modify_mmd(phydev, devad, regnum, mask, set);
825 	phy_unlock_mdio_bus(phydev);
826 
827 	return ret;
828 }
829 EXPORT_SYMBOL_GPL(phy_modify_mmd);
830 
831 static int __phy_read_page(struct phy_device *phydev)
832 {
833 	if (WARN_ONCE(!phydev->drv->read_page, "read_page callback not available, PHY driver not loaded?\n"))
834 		return -EOPNOTSUPP;
835 
836 	return phydev->drv->read_page(phydev);
837 }
838 
839 static int __phy_write_page(struct phy_device *phydev, int page)
840 {
841 	if (WARN_ONCE(!phydev->drv->write_page, "write_page callback not available, PHY driver not loaded?\n"))
842 		return -EOPNOTSUPP;
843 
844 	return phydev->drv->write_page(phydev, page);
845 }
846 
847 /**
848  * phy_save_page() - take the bus lock and save the current page
849  * @phydev: a pointer to a &struct phy_device
850  *
851  * Take the MDIO bus lock, and return the current page number. On error,
852  * returns a negative errno. phy_restore_page() must always be called
853  * after this, irrespective of success or failure of this call.
854  */
855 int phy_save_page(struct phy_device *phydev)
856 {
857 	phy_lock_mdio_bus(phydev);
858 	return __phy_read_page(phydev);
859 }
860 EXPORT_SYMBOL_GPL(phy_save_page);
861 
862 /**
863  * phy_select_page() - take the bus lock, save the current page, and set a page
864  * @phydev: a pointer to a &struct phy_device
865  * @page: desired page
866  *
867  * Take the MDIO bus lock to protect against concurrent access, save the
868  * current PHY page, and set the current page.  On error, returns a
869  * negative errno, otherwise returns the previous page number.
870  * phy_restore_page() must always be called after this, irrespective
871  * of success or failure of this call.
872  */
873 int phy_select_page(struct phy_device *phydev, int page)
874 {
875 	int ret, oldpage;
876 
877 	oldpage = ret = phy_save_page(phydev);
878 	if (ret < 0)
879 		return ret;
880 
881 	if (oldpage != page) {
882 		ret = __phy_write_page(phydev, page);
883 		if (ret < 0)
884 			return ret;
885 	}
886 
887 	return oldpage;
888 }
889 EXPORT_SYMBOL_GPL(phy_select_page);
890 
891 /**
892  * phy_restore_page() - restore the page register and release the bus lock
893  * @phydev: a pointer to a &struct phy_device
894  * @oldpage: the old page, return value from phy_save_page() or phy_select_page()
895  * @ret: operation's return code
896  *
897  * Release the MDIO bus lock, restoring @oldpage if it is a valid page.
898  * This function propagates the earliest error code from the group of
899  * operations.
900  *
901  * Returns:
902  *   @oldpage if it was a negative value, otherwise
903  *   @ret if it was a negative errno value, otherwise
904  *   phy_write_page()'s negative value if it were in error, otherwise
905  *   @ret.
906  */
907 int phy_restore_page(struct phy_device *phydev, int oldpage, int ret)
908 {
909 	int r;
910 
911 	if (oldpage >= 0) {
912 		r = __phy_write_page(phydev, oldpage);
913 
914 		/* Propagate the operation return code if the page write
915 		 * was successful.
916 		 */
917 		if (ret >= 0 && r < 0)
918 			ret = r;
919 	} else {
920 		/* Propagate the phy page selection error code */
921 		ret = oldpage;
922 	}
923 
924 	phy_unlock_mdio_bus(phydev);
925 
926 	return ret;
927 }
928 EXPORT_SYMBOL_GPL(phy_restore_page);
929 
930 /**
931  * phy_read_paged() - Convenience function for reading a paged register
932  * @phydev: a pointer to a &struct phy_device
933  * @page: the page for the phy
934  * @regnum: register number
935  *
936  * Same rules as for phy_read().
937  */
938 int phy_read_paged(struct phy_device *phydev, int page, u32 regnum)
939 {
940 	int ret = 0, oldpage;
941 
942 	oldpage = phy_select_page(phydev, page);
943 	if (oldpage >= 0)
944 		ret = __phy_read(phydev, regnum);
945 
946 	return phy_restore_page(phydev, oldpage, ret);
947 }
948 EXPORT_SYMBOL(phy_read_paged);
949 
950 /**
951  * phy_write_paged() - Convenience function for writing a paged register
952  * @phydev: a pointer to a &struct phy_device
953  * @page: the page for the phy
954  * @regnum: register number
955  * @val: value to write
956  *
957  * Same rules as for phy_write().
958  */
959 int phy_write_paged(struct phy_device *phydev, int page, u32 regnum, u16 val)
960 {
961 	int ret = 0, oldpage;
962 
963 	oldpage = phy_select_page(phydev, page);
964 	if (oldpage >= 0)
965 		ret = __phy_write(phydev, regnum, val);
966 
967 	return phy_restore_page(phydev, oldpage, ret);
968 }
969 EXPORT_SYMBOL(phy_write_paged);
970 
971 /**
972  * phy_modify_paged_changed() - Function for modifying a paged register
973  * @phydev: a pointer to a &struct phy_device
974  * @page: the page for the phy
975  * @regnum: register number
976  * @mask: bit mask of bits to clear
977  * @set: bit mask of bits to set
978  *
979  * Returns negative errno, 0 if there was no change, and 1 in case of change
980  */
981 int phy_modify_paged_changed(struct phy_device *phydev, int page, u32 regnum,
982 			     u16 mask, u16 set)
983 {
984 	int ret = 0, oldpage;
985 
986 	oldpage = phy_select_page(phydev, page);
987 	if (oldpage >= 0)
988 		ret = __phy_modify_changed(phydev, regnum, mask, set);
989 
990 	return phy_restore_page(phydev, oldpage, ret);
991 }
992 EXPORT_SYMBOL(phy_modify_paged_changed);
993 
994 /**
995  * phy_modify_paged() - Convenience function for modifying a paged register
996  * @phydev: a pointer to a &struct phy_device
997  * @page: the page for the phy
998  * @regnum: register number
999  * @mask: bit mask of bits to clear
1000  * @set: bit mask of bits to set
1001  *
1002  * Same rules as for phy_read() and phy_write().
1003  */
1004 int phy_modify_paged(struct phy_device *phydev, int page, u32 regnum,
1005 		     u16 mask, u16 set)
1006 {
1007 	int ret = phy_modify_paged_changed(phydev, page, regnum, mask, set);
1008 
1009 	return ret < 0 ? ret : 0;
1010 }
1011 EXPORT_SYMBOL(phy_modify_paged);
1012