xref: /openbmc/linux/drivers/net/phy/smsc.c (revision 2dec9e09)
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 	return rc;
125 }
126 
127 static int smsc_phy_reset(struct phy_device *phydev)
128 {
129 	int rc = phy_read(phydev, MII_LAN83C185_SPECIAL_MODES);
130 	if (rc < 0)
131 		return rc;
132 
133 	/* If the SMSC PHY is in power down mode, then set it
134 	 * in all capable mode before using it.
135 	 */
136 	if ((rc & MII_LAN83C185_MODE_MASK) == MII_LAN83C185_MODE_POWERDOWN) {
137 		/* set "all capable" mode */
138 		rc |= MII_LAN83C185_MODE_ALL;
139 		phy_write(phydev, MII_LAN83C185_SPECIAL_MODES, rc);
140 	}
141 
142 	/* reset the phy */
143 	return genphy_soft_reset(phydev);
144 }
145 
146 static int lan87xx_config_aneg(struct phy_device *phydev)
147 {
148 	int rc;
149 	int val;
150 
151 	switch (phydev->mdix_ctrl) {
152 	case ETH_TP_MDI:
153 		val = SPECIAL_CTRL_STS_OVRRD_AMDIX_;
154 		break;
155 	case ETH_TP_MDI_X:
156 		val = SPECIAL_CTRL_STS_OVRRD_AMDIX_ |
157 			SPECIAL_CTRL_STS_AMDIX_STATE_;
158 		break;
159 	case ETH_TP_MDI_AUTO:
160 		val = SPECIAL_CTRL_STS_AMDIX_ENABLE_;
161 		break;
162 	default:
163 		return genphy_config_aneg(phydev);
164 	}
165 
166 	rc = phy_read(phydev, SPECIAL_CTRL_STS);
167 	if (rc < 0)
168 		return rc;
169 
170 	rc &= ~(SPECIAL_CTRL_STS_OVRRD_AMDIX_ |
171 		SPECIAL_CTRL_STS_AMDIX_ENABLE_ |
172 		SPECIAL_CTRL_STS_AMDIX_STATE_);
173 	rc |= val;
174 	phy_write(phydev, SPECIAL_CTRL_STS, rc);
175 
176 	phydev->mdix = phydev->mdix_ctrl;
177 	return genphy_config_aneg(phydev);
178 }
179 
180 static int lan95xx_config_aneg_ext(struct phy_device *phydev)
181 {
182 	int rc;
183 
184 	if (phydev->phy_id != 0x0007c0f0) /* not (LAN9500A or LAN9505A) */
185 		return lan87xx_config_aneg(phydev);
186 
187 	/* Extend Manual AutoMDIX timer */
188 	rc = phy_read(phydev, PHY_EDPD_CONFIG);
189 	if (rc < 0)
190 		return rc;
191 
192 	rc |= PHY_EDPD_CONFIG_EXT_CROSSOVER_;
193 	phy_write(phydev, PHY_EDPD_CONFIG, rc);
194 	return lan87xx_config_aneg(phydev);
195 }
196 
197 /*
198  * The LAN87xx suffers from rare absence of the ENERGYON-bit when Ethernet cable
199  * plugs in while LAN87xx is in Energy Detect Power-Down mode. This leads to
200  * unstable detection of plugging in Ethernet cable.
201  * This workaround disables Energy Detect Power-Down mode and waiting for
202  * response on link pulses to detect presence of plugged Ethernet cable.
203  * The Energy Detect Power-Down mode is enabled again in the end of procedure to
204  * save approximately 220 mW of power if cable is unplugged.
205  * The workaround is only applicable to poll mode. Energy Detect Power-Down may
206  * not be used in interrupt mode lest link change detection becomes unreliable.
207  */
208 static int lan87xx_read_status(struct phy_device *phydev)
209 {
210 	struct smsc_phy_priv *priv = phydev->priv;
211 
212 	int err = genphy_read_status(phydev);
213 
214 	if (!phydev->link && priv->energy_enable && phydev->irq == PHY_POLL) {
215 		/* Disable EDPD to wake up PHY */
216 		int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
217 		if (rc < 0)
218 			return rc;
219 
220 		rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
221 			       rc & ~MII_LAN83C185_EDPWRDOWN);
222 		if (rc < 0)
223 			return rc;
224 
225 		/* Wait max 640 ms to detect energy and the timeout is not
226 		 * an actual error.
227 		 */
228 		read_poll_timeout(phy_read, rc,
229 				  rc & MII_LAN83C185_ENERGYON || rc < 0,
230 				  10000, 640000, true, phydev,
231 				  MII_LAN83C185_CTRL_STATUS);
232 		if (rc < 0)
233 			return rc;
234 
235 		/* Re-enable EDPD */
236 		rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
237 		if (rc < 0)
238 			return rc;
239 
240 		rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
241 			       rc | MII_LAN83C185_EDPWRDOWN);
242 		if (rc < 0)
243 			return rc;
244 	}
245 
246 	return err;
247 }
248 
249 static int smsc_get_sset_count(struct phy_device *phydev)
250 {
251 	return ARRAY_SIZE(smsc_hw_stats);
252 }
253 
254 static void smsc_get_strings(struct phy_device *phydev, u8 *data)
255 {
256 	int i;
257 
258 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++) {
259 		strncpy(data + i * ETH_GSTRING_LEN,
260 		       smsc_hw_stats[i].string, ETH_GSTRING_LEN);
261 	}
262 }
263 
264 static u64 smsc_get_stat(struct phy_device *phydev, int i)
265 {
266 	struct smsc_hw_stat stat = smsc_hw_stats[i];
267 	int val;
268 	u64 ret;
269 
270 	val = phy_read(phydev, stat.reg);
271 	if (val < 0)
272 		ret = U64_MAX;
273 	else
274 		ret = val;
275 
276 	return ret;
277 }
278 
279 static void smsc_get_stats(struct phy_device *phydev,
280 			   struct ethtool_stats *stats, u64 *data)
281 {
282 	int i;
283 
284 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++)
285 		data[i] = smsc_get_stat(phydev, i);
286 }
287 
288 static void smsc_phy_remove(struct phy_device *phydev)
289 {
290 	struct smsc_phy_priv *priv = phydev->priv;
291 
292 	clk_disable_unprepare(priv->refclk);
293 	clk_put(priv->refclk);
294 }
295 
296 static int smsc_phy_probe(struct phy_device *phydev)
297 {
298 	struct device *dev = &phydev->mdio.dev;
299 	struct device_node *of_node = dev->of_node;
300 	struct smsc_phy_priv *priv;
301 	int ret;
302 
303 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
304 	if (!priv)
305 		return -ENOMEM;
306 
307 	priv->energy_enable = true;
308 
309 	if (of_property_read_bool(of_node, "smsc,disable-energy-detect"))
310 		priv->energy_enable = false;
311 
312 	phydev->priv = priv;
313 
314 	/* Make clk optional to keep DTB backward compatibility. */
315 	priv->refclk = clk_get_optional(dev, NULL);
316 	if (IS_ERR(priv->refclk))
317 		return dev_err_probe(dev, PTR_ERR(priv->refclk),
318 				     "Failed to request clock\n");
319 
320 	ret = clk_prepare_enable(priv->refclk);
321 	if (ret)
322 		return ret;
323 
324 	ret = clk_set_rate(priv->refclk, 50 * 1000 * 1000);
325 	if (ret) {
326 		clk_disable_unprepare(priv->refclk);
327 		return ret;
328 	}
329 
330 	return 0;
331 }
332 
333 static struct phy_driver smsc_phy_driver[] = {
334 {
335 	.phy_id		= 0x0007c0a0, /* OUI=0x00800f, Model#=0x0a */
336 	.phy_id_mask	= 0xfffffff0,
337 	.name		= "SMSC LAN83C185",
338 
339 	/* PHY_BASIC_FEATURES */
340 
341 	.probe		= smsc_phy_probe,
342 
343 	/* basic functions */
344 	.config_init	= smsc_phy_config_init,
345 	.soft_reset	= smsc_phy_reset,
346 
347 	/* IRQ related */
348 	.config_intr	= smsc_phy_config_intr,
349 	.handle_interrupt = smsc_phy_handle_interrupt,
350 
351 	.suspend	= genphy_suspend,
352 	.resume		= genphy_resume,
353 }, {
354 	.phy_id		= 0x0007c0b0, /* OUI=0x00800f, Model#=0x0b */
355 	.phy_id_mask	= 0xfffffff0,
356 	.name		= "SMSC LAN8187",
357 
358 	/* PHY_BASIC_FEATURES */
359 
360 	.probe		= smsc_phy_probe,
361 
362 	/* basic functions */
363 	.config_init	= smsc_phy_config_init,
364 	.soft_reset	= smsc_phy_reset,
365 
366 	/* IRQ related */
367 	.config_intr	= smsc_phy_config_intr,
368 	.handle_interrupt = smsc_phy_handle_interrupt,
369 
370 	/* Statistics */
371 	.get_sset_count = smsc_get_sset_count,
372 	.get_strings	= smsc_get_strings,
373 	.get_stats	= smsc_get_stats,
374 
375 	.suspend	= genphy_suspend,
376 	.resume		= genphy_resume,
377 }, {
378 	/* This covers internal PHY (phy_id: 0x0007C0C3) for
379 	 * LAN9500 (PID: 0x9500), LAN9514 (PID: 0xec00), LAN9505 (PID: 0x9505)
380 	 */
381 	.phy_id		= 0x0007c0c0, /* OUI=0x00800f, Model#=0x0c */
382 	.phy_id_mask	= 0xfffffff0,
383 	.name		= "SMSC LAN8700",
384 
385 	/* PHY_BASIC_FEATURES */
386 
387 	.probe		= smsc_phy_probe,
388 
389 	/* basic functions */
390 	.read_status	= lan87xx_read_status,
391 	.config_init	= smsc_phy_config_init,
392 	.soft_reset	= smsc_phy_reset,
393 	.config_aneg	= lan87xx_config_aneg,
394 
395 	/* IRQ related */
396 	.config_intr	= smsc_phy_config_intr,
397 	.handle_interrupt = smsc_phy_handle_interrupt,
398 
399 	/* Statistics */
400 	.get_sset_count = smsc_get_sset_count,
401 	.get_strings	= smsc_get_strings,
402 	.get_stats	= smsc_get_stats,
403 
404 	.suspend	= genphy_suspend,
405 	.resume		= genphy_resume,
406 }, {
407 	.phy_id		= 0x0007c0d0, /* OUI=0x00800f, Model#=0x0d */
408 	.phy_id_mask	= 0xfffffff0,
409 	.name		= "SMSC LAN911x Internal PHY",
410 
411 	/* PHY_BASIC_FEATURES */
412 
413 	.probe		= smsc_phy_probe,
414 
415 	/* IRQ related */
416 	.config_intr	= smsc_phy_config_intr,
417 	.handle_interrupt = smsc_phy_handle_interrupt,
418 
419 	.suspend	= genphy_suspend,
420 	.resume		= genphy_resume,
421 }, {
422 	/* This covers internal PHY (phy_id: 0x0007C0F0) for
423 	 * LAN9500A (PID: 0x9E00), LAN9505A (PID: 0x9E01)
424 	 */
425 	.phy_id		= 0x0007c0f0, /* OUI=0x00800f, Model#=0x0f */
426 	.phy_id_mask	= 0xfffffff0,
427 	.name		= "SMSC LAN8710/LAN8720",
428 
429 	/* PHY_BASIC_FEATURES */
430 
431 	.probe		= smsc_phy_probe,
432 	.remove		= smsc_phy_remove,
433 
434 	/* basic functions */
435 	.read_status	= lan87xx_read_status,
436 	.config_init	= smsc_phy_config_init,
437 	.soft_reset	= smsc_phy_reset,
438 	.config_aneg	= lan95xx_config_aneg_ext,
439 
440 	/* IRQ related */
441 	.config_intr	= smsc_phy_config_intr,
442 	.handle_interrupt = smsc_phy_handle_interrupt,
443 
444 	/* Statistics */
445 	.get_sset_count = smsc_get_sset_count,
446 	.get_strings	= smsc_get_strings,
447 	.get_stats	= smsc_get_stats,
448 
449 	.suspend	= genphy_suspend,
450 	.resume		= genphy_resume,
451 }, {
452 	.phy_id		= 0x0007c110,
453 	.phy_id_mask	= 0xfffffff0,
454 	.name		= "SMSC LAN8740",
455 
456 	/* PHY_BASIC_FEATURES */
457 	.flags		= PHY_RST_AFTER_CLK_EN,
458 
459 	.probe		= smsc_phy_probe,
460 
461 	/* basic functions */
462 	.read_status	= lan87xx_read_status,
463 	.config_init	= smsc_phy_config_init,
464 	.soft_reset	= smsc_phy_reset,
465 
466 	/* IRQ related */
467 	.config_intr	= smsc_phy_config_intr,
468 	.handle_interrupt = smsc_phy_handle_interrupt,
469 
470 	/* Statistics */
471 	.get_sset_count = smsc_get_sset_count,
472 	.get_strings	= smsc_get_strings,
473 	.get_stats	= smsc_get_stats,
474 
475 	.suspend	= genphy_suspend,
476 	.resume		= genphy_resume,
477 }, {
478 	.phy_id		= 0x0007c130,	/* 0x0007c130 and 0x0007c131 */
479 	/* This mask (0xfffffff2) is to differentiate from
480 	 * LAN88xx (phy_id 0x0007c132)
481 	 * and allows future phy_id revisions.
482 	 */
483 	.phy_id_mask	= 0xfffffff2,
484 	.name		= "Microchip LAN8742",
485 
486 	/* PHY_BASIC_FEATURES */
487 	.flags		= PHY_RST_AFTER_CLK_EN,
488 
489 	.probe		= smsc_phy_probe,
490 
491 	/* basic functions */
492 	.read_status	= lan87xx_read_status,
493 	.config_init	= smsc_phy_config_init,
494 	.soft_reset	= smsc_phy_reset,
495 
496 	/* IRQ related */
497 	.config_intr	= smsc_phy_config_intr,
498 	.handle_interrupt = smsc_phy_handle_interrupt,
499 
500 	/* Statistics */
501 	.get_sset_count = smsc_get_sset_count,
502 	.get_strings	= smsc_get_strings,
503 	.get_stats	= smsc_get_stats,
504 
505 	.suspend	= genphy_suspend,
506 	.resume		= genphy_resume,
507 } };
508 
509 module_phy_driver(smsc_phy_driver);
510 
511 MODULE_DESCRIPTION("SMSC PHY driver");
512 MODULE_AUTHOR("Herbert Valerio Riedel");
513 MODULE_LICENSE("GPL");
514 
515 static struct mdio_device_id __maybe_unused smsc_tbl[] = {
516 	{ 0x0007c0a0, 0xfffffff0 },
517 	{ 0x0007c0b0, 0xfffffff0 },
518 	{ 0x0007c0c0, 0xfffffff0 },
519 	{ 0x0007c0d0, 0xfffffff0 },
520 	{ 0x0007c0f0, 0xfffffff0 },
521 	{ 0x0007c110, 0xfffffff0 },
522 	{ 0x0007c130, 0xfffffff2 },
523 	{ }
524 };
525 
526 MODULE_DEVICE_TABLE(mdio, smsc_tbl);
527