xref: /openbmc/linux/drivers/net/phy/smsc.c (revision 2dd6532e)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * drivers/net/phy/smsc.c
4  *
5  * Driver for SMSC PHYs
6  *
7  * Author: Herbert Valerio Riedel
8  *
9  * Copyright (c) 2006 Herbert Valerio Riedel <hvr@gnu.org>
10  *
11  * Support added for SMSC LAN8187 and LAN8700 by steve.glendinning@shawell.net
12  *
13  */
14 
15 #include <linux/clk.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/mii.h>
19 #include <linux/ethtool.h>
20 #include <linux/of.h>
21 #include <linux/phy.h>
22 #include <linux/netdevice.h>
23 #include <linux/smscphy.h>
24 
25 /* Vendor-specific PHY Definitions */
26 /* EDPD NLP / crossover time configuration */
27 #define PHY_EDPD_CONFIG			16
28 #define PHY_EDPD_CONFIG_EXT_CROSSOVER_	0x0001
29 
30 /* Control/Status Indication Register */
31 #define SPECIAL_CTRL_STS		27
32 #define SPECIAL_CTRL_STS_OVRRD_AMDIX_	0x8000
33 #define SPECIAL_CTRL_STS_AMDIX_ENABLE_	0x4000
34 #define SPECIAL_CTRL_STS_AMDIX_STATE_	0x2000
35 
36 struct smsc_hw_stat {
37 	const char *string;
38 	u8 reg;
39 	u8 bits;
40 };
41 
42 static struct smsc_hw_stat smsc_hw_stats[] = {
43 	{ "phy_symbol_errors", 26, 16},
44 };
45 
46 struct smsc_phy_priv {
47 	u16 intmask;
48 	bool energy_enable;
49 	struct clk *refclk;
50 };
51 
52 static int smsc_phy_ack_interrupt(struct phy_device *phydev)
53 {
54 	int rc = phy_read(phydev, MII_LAN83C185_ISF);
55 
56 	return rc < 0 ? rc : 0;
57 }
58 
59 static int smsc_phy_config_intr(struct phy_device *phydev)
60 {
61 	struct smsc_phy_priv *priv = phydev->priv;
62 	int rc;
63 
64 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
65 		rc = smsc_phy_ack_interrupt(phydev);
66 		if (rc)
67 			return rc;
68 
69 		priv->intmask = MII_LAN83C185_ISF_INT4 | MII_LAN83C185_ISF_INT6;
70 		if (priv->energy_enable)
71 			priv->intmask |= MII_LAN83C185_ISF_INT7;
72 
73 		rc = phy_write(phydev, MII_LAN83C185_IM, priv->intmask);
74 	} else {
75 		priv->intmask = 0;
76 
77 		rc = phy_write(phydev, MII_LAN83C185_IM, 0);
78 		if (rc)
79 			return rc;
80 
81 		rc = smsc_phy_ack_interrupt(phydev);
82 	}
83 
84 	return rc < 0 ? rc : 0;
85 }
86 
87 static irqreturn_t smsc_phy_handle_interrupt(struct phy_device *phydev)
88 {
89 	struct smsc_phy_priv *priv = phydev->priv;
90 	int irq_status;
91 
92 	irq_status = phy_read(phydev, MII_LAN83C185_ISF);
93 	if (irq_status < 0) {
94 		if (irq_status != -ENODEV)
95 			phy_error(phydev);
96 
97 		return IRQ_NONE;
98 	}
99 
100 	if (!(irq_status & priv->intmask))
101 		return IRQ_NONE;
102 
103 	phy_trigger_machine(phydev);
104 
105 	return IRQ_HANDLED;
106 }
107 
108 static int smsc_phy_config_init(struct phy_device *phydev)
109 {
110 	struct smsc_phy_priv *priv = phydev->priv;
111 	int rc;
112 
113 	if (!priv->energy_enable || phydev->irq != PHY_POLL)
114 		return 0;
115 
116 	rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
117 
118 	if (rc < 0)
119 		return rc;
120 
121 	/* Enable energy detect mode for this SMSC Transceivers */
122 	rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
123 		       rc | MII_LAN83C185_EDPWRDOWN);
124 	if (rc < 0)
125 		return rc;
126 
127 	return smsc_phy_ack_interrupt(phydev);
128 }
129 
130 static int smsc_phy_reset(struct phy_device *phydev)
131 {
132 	int rc = phy_read(phydev, MII_LAN83C185_SPECIAL_MODES);
133 	if (rc < 0)
134 		return rc;
135 
136 	/* If the SMSC PHY is in power down mode, then set it
137 	 * in all capable mode before using it.
138 	 */
139 	if ((rc & MII_LAN83C185_MODE_MASK) == MII_LAN83C185_MODE_POWERDOWN) {
140 		/* set "all capable" mode */
141 		rc |= MII_LAN83C185_MODE_ALL;
142 		phy_write(phydev, MII_LAN83C185_SPECIAL_MODES, rc);
143 	}
144 
145 	/* reset the phy */
146 	return genphy_soft_reset(phydev);
147 }
148 
149 static int lan911x_config_init(struct phy_device *phydev)
150 {
151 	return smsc_phy_ack_interrupt(phydev);
152 }
153 
154 static int lan87xx_config_aneg(struct phy_device *phydev)
155 {
156 	int rc;
157 	int val;
158 
159 	switch (phydev->mdix_ctrl) {
160 	case ETH_TP_MDI:
161 		val = SPECIAL_CTRL_STS_OVRRD_AMDIX_;
162 		break;
163 	case ETH_TP_MDI_X:
164 		val = SPECIAL_CTRL_STS_OVRRD_AMDIX_ |
165 			SPECIAL_CTRL_STS_AMDIX_STATE_;
166 		break;
167 	case ETH_TP_MDI_AUTO:
168 		val = SPECIAL_CTRL_STS_AMDIX_ENABLE_;
169 		break;
170 	default:
171 		return genphy_config_aneg(phydev);
172 	}
173 
174 	rc = phy_read(phydev, SPECIAL_CTRL_STS);
175 	if (rc < 0)
176 		return rc;
177 
178 	rc &= ~(SPECIAL_CTRL_STS_OVRRD_AMDIX_ |
179 		SPECIAL_CTRL_STS_AMDIX_ENABLE_ |
180 		SPECIAL_CTRL_STS_AMDIX_STATE_);
181 	rc |= val;
182 	phy_write(phydev, SPECIAL_CTRL_STS, rc);
183 
184 	phydev->mdix = phydev->mdix_ctrl;
185 	return genphy_config_aneg(phydev);
186 }
187 
188 static int lan95xx_config_aneg_ext(struct phy_device *phydev)
189 {
190 	int rc;
191 
192 	if (phydev->phy_id != 0x0007c0f0) /* not (LAN9500A or LAN9505A) */
193 		return lan87xx_config_aneg(phydev);
194 
195 	/* Extend Manual AutoMDIX timer */
196 	rc = phy_read(phydev, PHY_EDPD_CONFIG);
197 	if (rc < 0)
198 		return rc;
199 
200 	rc |= PHY_EDPD_CONFIG_EXT_CROSSOVER_;
201 	phy_write(phydev, PHY_EDPD_CONFIG, rc);
202 	return lan87xx_config_aneg(phydev);
203 }
204 
205 /*
206  * The LAN87xx suffers from rare absence of the ENERGYON-bit when Ethernet cable
207  * plugs in while LAN87xx is in Energy Detect Power-Down mode. This leads to
208  * unstable detection of plugging in Ethernet cable.
209  * This workaround disables Energy Detect Power-Down mode and waiting for
210  * response on link pulses to detect presence of plugged Ethernet cable.
211  * The Energy Detect Power-Down mode is enabled again in the end of procedure to
212  * save approximately 220 mW of power if cable is unplugged.
213  * The workaround is only applicable to poll mode. Energy Detect Power-Down may
214  * not be used in interrupt mode lest link change detection becomes unreliable.
215  */
216 static int lan87xx_read_status(struct phy_device *phydev)
217 {
218 	struct smsc_phy_priv *priv = phydev->priv;
219 
220 	int err = genphy_read_status(phydev);
221 
222 	if (!phydev->link && priv->energy_enable && phydev->irq == PHY_POLL) {
223 		/* Disable EDPD to wake up PHY */
224 		int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
225 		if (rc < 0)
226 			return rc;
227 
228 		rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
229 			       rc & ~MII_LAN83C185_EDPWRDOWN);
230 		if (rc < 0)
231 			return rc;
232 
233 		/* Wait max 640 ms to detect energy and the timeout is not
234 		 * an actual error.
235 		 */
236 		read_poll_timeout(phy_read, rc,
237 				  rc & MII_LAN83C185_ENERGYON || rc < 0,
238 				  10000, 640000, true, phydev,
239 				  MII_LAN83C185_CTRL_STATUS);
240 		if (rc < 0)
241 			return rc;
242 
243 		/* Re-enable EDPD */
244 		rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
245 		if (rc < 0)
246 			return rc;
247 
248 		rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
249 			       rc | MII_LAN83C185_EDPWRDOWN);
250 		if (rc < 0)
251 			return rc;
252 	}
253 
254 	return err;
255 }
256 
257 static int smsc_get_sset_count(struct phy_device *phydev)
258 {
259 	return ARRAY_SIZE(smsc_hw_stats);
260 }
261 
262 static void smsc_get_strings(struct phy_device *phydev, u8 *data)
263 {
264 	int i;
265 
266 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++) {
267 		strncpy(data + i * ETH_GSTRING_LEN,
268 		       smsc_hw_stats[i].string, ETH_GSTRING_LEN);
269 	}
270 }
271 
272 static u64 smsc_get_stat(struct phy_device *phydev, int i)
273 {
274 	struct smsc_hw_stat stat = smsc_hw_stats[i];
275 	int val;
276 	u64 ret;
277 
278 	val = phy_read(phydev, stat.reg);
279 	if (val < 0)
280 		ret = U64_MAX;
281 	else
282 		ret = val;
283 
284 	return ret;
285 }
286 
287 static void smsc_get_stats(struct phy_device *phydev,
288 			   struct ethtool_stats *stats, u64 *data)
289 {
290 	int i;
291 
292 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++)
293 		data[i] = smsc_get_stat(phydev, i);
294 }
295 
296 static void smsc_phy_remove(struct phy_device *phydev)
297 {
298 	struct smsc_phy_priv *priv = phydev->priv;
299 
300 	clk_disable_unprepare(priv->refclk);
301 	clk_put(priv->refclk);
302 }
303 
304 static int smsc_phy_probe(struct phy_device *phydev)
305 {
306 	struct device *dev = &phydev->mdio.dev;
307 	struct device_node *of_node = dev->of_node;
308 	struct smsc_phy_priv *priv;
309 	int ret;
310 
311 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
312 	if (!priv)
313 		return -ENOMEM;
314 
315 	priv->energy_enable = true;
316 
317 	if (of_property_read_bool(of_node, "smsc,disable-energy-detect"))
318 		priv->energy_enable = false;
319 
320 	phydev->priv = priv;
321 
322 	/* Make clk optional to keep DTB backward compatibility. */
323 	priv->refclk = clk_get_optional(dev, NULL);
324 	if (IS_ERR(priv->refclk))
325 		return dev_err_probe(dev, PTR_ERR(priv->refclk),
326 				     "Failed to request clock\n");
327 
328 	ret = clk_prepare_enable(priv->refclk);
329 	if (ret)
330 		return ret;
331 
332 	ret = clk_set_rate(priv->refclk, 50 * 1000 * 1000);
333 	if (ret) {
334 		clk_disable_unprepare(priv->refclk);
335 		return ret;
336 	}
337 
338 	return 0;
339 }
340 
341 static struct phy_driver smsc_phy_driver[] = {
342 {
343 	.phy_id		= 0x0007c0a0, /* OUI=0x00800f, Model#=0x0a */
344 	.phy_id_mask	= 0xfffffff0,
345 	.name		= "SMSC LAN83C185",
346 
347 	/* PHY_BASIC_FEATURES */
348 
349 	.probe		= smsc_phy_probe,
350 
351 	/* basic functions */
352 	.config_init	= smsc_phy_config_init,
353 	.soft_reset	= smsc_phy_reset,
354 
355 	/* IRQ related */
356 	.config_intr	= smsc_phy_config_intr,
357 	.handle_interrupt = smsc_phy_handle_interrupt,
358 
359 	.suspend	= genphy_suspend,
360 	.resume		= genphy_resume,
361 }, {
362 	.phy_id		= 0x0007c0b0, /* OUI=0x00800f, Model#=0x0b */
363 	.phy_id_mask	= 0xfffffff0,
364 	.name		= "SMSC LAN8187",
365 
366 	/* PHY_BASIC_FEATURES */
367 
368 	.probe		= smsc_phy_probe,
369 
370 	/* basic functions */
371 	.config_init	= smsc_phy_config_init,
372 	.soft_reset	= smsc_phy_reset,
373 
374 	/* IRQ related */
375 	.config_intr	= smsc_phy_config_intr,
376 	.handle_interrupt = smsc_phy_handle_interrupt,
377 
378 	/* Statistics */
379 	.get_sset_count = smsc_get_sset_count,
380 	.get_strings	= smsc_get_strings,
381 	.get_stats	= smsc_get_stats,
382 
383 	.suspend	= genphy_suspend,
384 	.resume		= genphy_resume,
385 }, {
386 	/* This covers internal PHY (phy_id: 0x0007C0C3) for
387 	 * LAN9500 (PID: 0x9500), LAN9514 (PID: 0xec00), LAN9505 (PID: 0x9505)
388 	 */
389 	.phy_id		= 0x0007c0c0, /* OUI=0x00800f, Model#=0x0c */
390 	.phy_id_mask	= 0xfffffff0,
391 	.name		= "SMSC LAN8700",
392 
393 	/* PHY_BASIC_FEATURES */
394 
395 	.probe		= smsc_phy_probe,
396 
397 	/* basic functions */
398 	.read_status	= lan87xx_read_status,
399 	.config_init	= smsc_phy_config_init,
400 	.soft_reset	= smsc_phy_reset,
401 	.config_aneg	= lan87xx_config_aneg,
402 
403 	/* IRQ related */
404 	.config_intr	= smsc_phy_config_intr,
405 	.handle_interrupt = smsc_phy_handle_interrupt,
406 
407 	/* Statistics */
408 	.get_sset_count = smsc_get_sset_count,
409 	.get_strings	= smsc_get_strings,
410 	.get_stats	= smsc_get_stats,
411 
412 	.suspend	= genphy_suspend,
413 	.resume		= genphy_resume,
414 }, {
415 	.phy_id		= 0x0007c0d0, /* OUI=0x00800f, Model#=0x0d */
416 	.phy_id_mask	= 0xfffffff0,
417 	.name		= "SMSC LAN911x Internal PHY",
418 
419 	/* PHY_BASIC_FEATURES */
420 
421 	.probe		= smsc_phy_probe,
422 
423 	/* basic functions */
424 	.config_init	= lan911x_config_init,
425 
426 	/* IRQ related */
427 	.config_intr	= smsc_phy_config_intr,
428 	.handle_interrupt = smsc_phy_handle_interrupt,
429 
430 	.suspend	= genphy_suspend,
431 	.resume		= genphy_resume,
432 }, {
433 	/* This covers internal PHY (phy_id: 0x0007C0F0) for
434 	 * LAN9500A (PID: 0x9E00), LAN9505A (PID: 0x9E01)
435 	 */
436 	.phy_id		= 0x0007c0f0, /* OUI=0x00800f, Model#=0x0f */
437 	.phy_id_mask	= 0xfffffff0,
438 	.name		= "SMSC LAN8710/LAN8720",
439 
440 	/* PHY_BASIC_FEATURES */
441 
442 	.probe		= smsc_phy_probe,
443 	.remove		= smsc_phy_remove,
444 
445 	/* basic functions */
446 	.read_status	= lan87xx_read_status,
447 	.config_init	= smsc_phy_config_init,
448 	.soft_reset	= smsc_phy_reset,
449 	.config_aneg	= lan95xx_config_aneg_ext,
450 
451 	/* IRQ related */
452 	.config_intr	= smsc_phy_config_intr,
453 	.handle_interrupt = smsc_phy_handle_interrupt,
454 
455 	/* Statistics */
456 	.get_sset_count = smsc_get_sset_count,
457 	.get_strings	= smsc_get_strings,
458 	.get_stats	= smsc_get_stats,
459 
460 	.suspend	= genphy_suspend,
461 	.resume		= genphy_resume,
462 }, {
463 	.phy_id		= 0x0007c110,
464 	.phy_id_mask	= 0xfffffff0,
465 	.name		= "SMSC LAN8740",
466 
467 	/* PHY_BASIC_FEATURES */
468 	.flags		= PHY_RST_AFTER_CLK_EN,
469 
470 	.probe		= smsc_phy_probe,
471 
472 	/* basic functions */
473 	.read_status	= lan87xx_read_status,
474 	.config_init	= smsc_phy_config_init,
475 	.soft_reset	= smsc_phy_reset,
476 
477 	/* IRQ related */
478 	.config_intr	= smsc_phy_config_intr,
479 	.handle_interrupt = smsc_phy_handle_interrupt,
480 
481 	/* Statistics */
482 	.get_sset_count = smsc_get_sset_count,
483 	.get_strings	= smsc_get_strings,
484 	.get_stats	= smsc_get_stats,
485 
486 	.suspend	= genphy_suspend,
487 	.resume		= genphy_resume,
488 }, {
489 	.phy_id		= 0x0007c130,	/* 0x0007c130 and 0x0007c131 */
490 	/* This mask (0xfffffff2) is to differentiate from
491 	 * LAN88xx (phy_id 0x0007c132)
492 	 * and allows future phy_id revisions.
493 	 */
494 	.phy_id_mask	= 0xfffffff2,
495 	.name		= "Microchip LAN8742",
496 
497 	/* PHY_BASIC_FEATURES */
498 	.flags		= PHY_RST_AFTER_CLK_EN,
499 
500 	.probe		= smsc_phy_probe,
501 
502 	/* basic functions */
503 	.read_status	= lan87xx_read_status,
504 	.config_init	= smsc_phy_config_init,
505 	.soft_reset	= smsc_phy_reset,
506 
507 	/* IRQ related */
508 	.config_intr	= smsc_phy_config_intr,
509 	.handle_interrupt = smsc_phy_handle_interrupt,
510 
511 	/* Statistics */
512 	.get_sset_count = smsc_get_sset_count,
513 	.get_strings	= smsc_get_strings,
514 	.get_stats	= smsc_get_stats,
515 
516 	.suspend	= genphy_suspend,
517 	.resume		= genphy_resume,
518 } };
519 
520 module_phy_driver(smsc_phy_driver);
521 
522 MODULE_DESCRIPTION("SMSC PHY driver");
523 MODULE_AUTHOR("Herbert Valerio Riedel");
524 MODULE_LICENSE("GPL");
525 
526 static struct mdio_device_id __maybe_unused smsc_tbl[] = {
527 	{ 0x0007c0a0, 0xfffffff0 },
528 	{ 0x0007c0b0, 0xfffffff0 },
529 	{ 0x0007c0c0, 0xfffffff0 },
530 	{ 0x0007c0d0, 0xfffffff0 },
531 	{ 0x0007c0f0, 0xfffffff0 },
532 	{ 0x0007c110, 0xfffffff0 },
533 	{ 0x0007c130, 0xfffffff2 },
534 	{ }
535 };
536 
537 MODULE_DEVICE_TABLE(mdio, smsc_tbl);
538