xref: /openbmc/linux/drivers/net/phy/smsc.c (revision be2b81b5)
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 };
50 
51 static int smsc_phy_ack_interrupt(struct phy_device *phydev)
52 {
53 	int rc = phy_read(phydev, MII_LAN83C185_ISF);
54 
55 	return rc < 0 ? rc : 0;
56 }
57 
58 static int smsc_phy_config_intr(struct phy_device *phydev)
59 {
60 	struct smsc_phy_priv *priv = phydev->priv;
61 	int rc;
62 
63 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED) {
64 		rc = smsc_phy_ack_interrupt(phydev);
65 		if (rc)
66 			return rc;
67 
68 		priv->intmask = MII_LAN83C185_ISF_INT4 | MII_LAN83C185_ISF_INT6;
69 		if (priv->energy_enable)
70 			priv->intmask |= MII_LAN83C185_ISF_INT7;
71 
72 		rc = phy_write(phydev, MII_LAN83C185_IM, priv->intmask);
73 	} else {
74 		priv->intmask = 0;
75 
76 		rc = phy_write(phydev, MII_LAN83C185_IM, 0);
77 		if (rc)
78 			return rc;
79 
80 		rc = smsc_phy_ack_interrupt(phydev);
81 	}
82 
83 	return rc < 0 ? rc : 0;
84 }
85 
86 static irqreturn_t smsc_phy_handle_interrupt(struct phy_device *phydev)
87 {
88 	struct smsc_phy_priv *priv = phydev->priv;
89 	int irq_status;
90 
91 	irq_status = phy_read(phydev, MII_LAN83C185_ISF);
92 	if (irq_status < 0) {
93 		if (irq_status != -ENODEV)
94 			phy_error(phydev);
95 
96 		return IRQ_NONE;
97 	}
98 
99 	if (!(irq_status & priv->intmask))
100 		return IRQ_NONE;
101 
102 	phy_trigger_machine(phydev);
103 
104 	return IRQ_HANDLED;
105 }
106 
107 static int smsc_phy_config_init(struct phy_device *phydev)
108 {
109 	struct smsc_phy_priv *priv = phydev->priv;
110 	int rc;
111 
112 	if (!priv->energy_enable || phydev->irq != PHY_POLL)
113 		return 0;
114 
115 	rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
116 
117 	if (rc < 0)
118 		return rc;
119 
120 	/* Enable energy detect mode for this SMSC Transceivers */
121 	rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
122 		       rc | MII_LAN83C185_EDPWRDOWN);
123 	return rc;
124 }
125 
126 static int smsc_phy_reset(struct phy_device *phydev)
127 {
128 	int rc = phy_read(phydev, MII_LAN83C185_SPECIAL_MODES);
129 	if (rc < 0)
130 		return rc;
131 
132 	/* If the SMSC PHY is in power down mode, then set it
133 	 * in all capable mode before using it.
134 	 */
135 	if ((rc & MII_LAN83C185_MODE_MASK) == MII_LAN83C185_MODE_POWERDOWN) {
136 		/* set "all capable" mode */
137 		rc |= MII_LAN83C185_MODE_ALL;
138 		phy_write(phydev, MII_LAN83C185_SPECIAL_MODES, rc);
139 	}
140 
141 	/* reset the phy */
142 	return genphy_soft_reset(phydev);
143 }
144 
145 static int lan87xx_config_aneg(struct phy_device *phydev)
146 {
147 	int rc;
148 	int val;
149 
150 	switch (phydev->mdix_ctrl) {
151 	case ETH_TP_MDI:
152 		val = SPECIAL_CTRL_STS_OVRRD_AMDIX_;
153 		break;
154 	case ETH_TP_MDI_X:
155 		val = SPECIAL_CTRL_STS_OVRRD_AMDIX_ |
156 			SPECIAL_CTRL_STS_AMDIX_STATE_;
157 		break;
158 	case ETH_TP_MDI_AUTO:
159 		val = SPECIAL_CTRL_STS_AMDIX_ENABLE_;
160 		break;
161 	default:
162 		return genphy_config_aneg(phydev);
163 	}
164 
165 	rc = phy_read(phydev, SPECIAL_CTRL_STS);
166 	if (rc < 0)
167 		return rc;
168 
169 	rc &= ~(SPECIAL_CTRL_STS_OVRRD_AMDIX_ |
170 		SPECIAL_CTRL_STS_AMDIX_ENABLE_ |
171 		SPECIAL_CTRL_STS_AMDIX_STATE_);
172 	rc |= val;
173 	phy_write(phydev, SPECIAL_CTRL_STS, rc);
174 
175 	phydev->mdix = phydev->mdix_ctrl;
176 	return genphy_config_aneg(phydev);
177 }
178 
179 static int lan95xx_config_aneg_ext(struct phy_device *phydev)
180 {
181 	int rc;
182 
183 	if (phydev->phy_id != 0x0007c0f0) /* not (LAN9500A or LAN9505A) */
184 		return lan87xx_config_aneg(phydev);
185 
186 	/* Extend Manual AutoMDIX timer */
187 	rc = phy_read(phydev, PHY_EDPD_CONFIG);
188 	if (rc < 0)
189 		return rc;
190 
191 	rc |= PHY_EDPD_CONFIG_EXT_CROSSOVER_;
192 	phy_write(phydev, PHY_EDPD_CONFIG, rc);
193 	return lan87xx_config_aneg(phydev);
194 }
195 
196 /*
197  * The LAN87xx suffers from rare absence of the ENERGYON-bit when Ethernet cable
198  * plugs in while LAN87xx is in Energy Detect Power-Down mode. This leads to
199  * unstable detection of plugging in Ethernet cable.
200  * This workaround disables Energy Detect Power-Down mode and waiting for
201  * response on link pulses to detect presence of plugged Ethernet cable.
202  * The Energy Detect Power-Down mode is enabled again in the end of procedure to
203  * save approximately 220 mW of power if cable is unplugged.
204  * The workaround is only applicable to poll mode. Energy Detect Power-Down may
205  * not be used in interrupt mode lest link change detection becomes unreliable.
206  */
207 static int lan87xx_read_status(struct phy_device *phydev)
208 {
209 	struct smsc_phy_priv *priv = phydev->priv;
210 
211 	int err = genphy_read_status(phydev);
212 
213 	if (!phydev->link && priv->energy_enable && phydev->irq == PHY_POLL) {
214 		/* Disable EDPD to wake up PHY */
215 		int rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
216 		if (rc < 0)
217 			return rc;
218 
219 		rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
220 			       rc & ~MII_LAN83C185_EDPWRDOWN);
221 		if (rc < 0)
222 			return rc;
223 
224 		/* Wait max 640 ms to detect energy and the timeout is not
225 		 * an actual error.
226 		 */
227 		read_poll_timeout(phy_read, rc,
228 				  rc & MII_LAN83C185_ENERGYON || rc < 0,
229 				  10000, 640000, true, phydev,
230 				  MII_LAN83C185_CTRL_STATUS);
231 		if (rc < 0)
232 			return rc;
233 
234 		/* Re-enable EDPD */
235 		rc = phy_read(phydev, MII_LAN83C185_CTRL_STATUS);
236 		if (rc < 0)
237 			return rc;
238 
239 		rc = phy_write(phydev, MII_LAN83C185_CTRL_STATUS,
240 			       rc | MII_LAN83C185_EDPWRDOWN);
241 		if (rc < 0)
242 			return rc;
243 	}
244 
245 	return err;
246 }
247 
248 static int smsc_get_sset_count(struct phy_device *phydev)
249 {
250 	return ARRAY_SIZE(smsc_hw_stats);
251 }
252 
253 static void smsc_get_strings(struct phy_device *phydev, u8 *data)
254 {
255 	int i;
256 
257 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++) {
258 		strncpy(data + i * ETH_GSTRING_LEN,
259 		       smsc_hw_stats[i].string, ETH_GSTRING_LEN);
260 	}
261 }
262 
263 static u64 smsc_get_stat(struct phy_device *phydev, int i)
264 {
265 	struct smsc_hw_stat stat = smsc_hw_stats[i];
266 	int val;
267 	u64 ret;
268 
269 	val = phy_read(phydev, stat.reg);
270 	if (val < 0)
271 		ret = U64_MAX;
272 	else
273 		ret = val;
274 
275 	return ret;
276 }
277 
278 static void smsc_get_stats(struct phy_device *phydev,
279 			   struct ethtool_stats *stats, u64 *data)
280 {
281 	int i;
282 
283 	for (i = 0; i < ARRAY_SIZE(smsc_hw_stats); i++)
284 		data[i] = smsc_get_stat(phydev, i);
285 }
286 
287 static int smsc_phy_probe(struct phy_device *phydev)
288 {
289 	struct device *dev = &phydev->mdio.dev;
290 	struct device_node *of_node = dev->of_node;
291 	struct smsc_phy_priv *priv;
292 	struct clk *refclk;
293 
294 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
295 	if (!priv)
296 		return -ENOMEM;
297 
298 	priv->energy_enable = true;
299 
300 	if (of_property_read_bool(of_node, "smsc,disable-energy-detect"))
301 		priv->energy_enable = false;
302 
303 	phydev->priv = priv;
304 
305 	/* Make clk optional to keep DTB backward compatibility. */
306 	refclk = devm_clk_get_optional_enabled(dev, NULL);
307 	if (IS_ERR(refclk))
308 		return dev_err_probe(dev, PTR_ERR(refclk),
309 				     "Failed to request clock\n");
310 
311 	return clk_set_rate(refclk, 50 * 1000 * 1000);
312 }
313 
314 static struct phy_driver smsc_phy_driver[] = {
315 {
316 	.phy_id		= 0x0007c0a0, /* OUI=0x00800f, Model#=0x0a */
317 	.phy_id_mask	= 0xfffffff0,
318 	.name		= "SMSC LAN83C185",
319 
320 	/* PHY_BASIC_FEATURES */
321 
322 	.probe		= smsc_phy_probe,
323 
324 	/* basic functions */
325 	.config_init	= smsc_phy_config_init,
326 	.soft_reset	= smsc_phy_reset,
327 
328 	/* IRQ related */
329 	.config_intr	= smsc_phy_config_intr,
330 	.handle_interrupt = smsc_phy_handle_interrupt,
331 
332 	.suspend	= genphy_suspend,
333 	.resume		= genphy_resume,
334 }, {
335 	.phy_id		= 0x0007c0b0, /* OUI=0x00800f, Model#=0x0b */
336 	.phy_id_mask	= 0xfffffff0,
337 	.name		= "SMSC LAN8187",
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 	/* Statistics */
352 	.get_sset_count = smsc_get_sset_count,
353 	.get_strings	= smsc_get_strings,
354 	.get_stats	= smsc_get_stats,
355 
356 	.suspend	= genphy_suspend,
357 	.resume		= genphy_resume,
358 }, {
359 	/* This covers internal PHY (phy_id: 0x0007C0C3) for
360 	 * LAN9500 (PID: 0x9500), LAN9514 (PID: 0xec00), LAN9505 (PID: 0x9505)
361 	 */
362 	.phy_id		= 0x0007c0c0, /* OUI=0x00800f, Model#=0x0c */
363 	.phy_id_mask	= 0xfffffff0,
364 	.name		= "SMSC LAN8700",
365 
366 	/* PHY_BASIC_FEATURES */
367 
368 	.probe		= smsc_phy_probe,
369 
370 	/* basic functions */
371 	.read_status	= lan87xx_read_status,
372 	.config_init	= smsc_phy_config_init,
373 	.soft_reset	= smsc_phy_reset,
374 	.config_aneg	= lan87xx_config_aneg,
375 
376 	/* IRQ related */
377 	.config_intr	= smsc_phy_config_intr,
378 	.handle_interrupt = smsc_phy_handle_interrupt,
379 
380 	/* Statistics */
381 	.get_sset_count = smsc_get_sset_count,
382 	.get_strings	= smsc_get_strings,
383 	.get_stats	= smsc_get_stats,
384 
385 	.suspend	= genphy_suspend,
386 	.resume		= genphy_resume,
387 }, {
388 	.phy_id		= 0x0007c0d0, /* OUI=0x00800f, Model#=0x0d */
389 	.phy_id_mask	= 0xfffffff0,
390 	.name		= "SMSC LAN911x Internal PHY",
391 
392 	/* PHY_BASIC_FEATURES */
393 
394 	.probe		= smsc_phy_probe,
395 
396 	/* IRQ related */
397 	.config_intr	= smsc_phy_config_intr,
398 	.handle_interrupt = smsc_phy_handle_interrupt,
399 
400 	.suspend	= genphy_suspend,
401 	.resume		= genphy_resume,
402 }, {
403 	/* This covers internal PHY (phy_id: 0x0007C0F0) for
404 	 * LAN9500A (PID: 0x9E00), LAN9505A (PID: 0x9E01)
405 	 */
406 	.phy_id		= 0x0007c0f0, /* OUI=0x00800f, Model#=0x0f */
407 	.phy_id_mask	= 0xfffffff0,
408 	.name		= "SMSC LAN8710/LAN8720",
409 
410 	/* PHY_BASIC_FEATURES */
411 
412 	.probe		= smsc_phy_probe,
413 
414 	/* basic functions */
415 	.read_status	= lan87xx_read_status,
416 	.config_init	= smsc_phy_config_init,
417 	.soft_reset	= smsc_phy_reset,
418 	.config_aneg	= lan95xx_config_aneg_ext,
419 
420 	/* IRQ related */
421 	.config_intr	= smsc_phy_config_intr,
422 	.handle_interrupt = smsc_phy_handle_interrupt,
423 
424 	/* Statistics */
425 	.get_sset_count = smsc_get_sset_count,
426 	.get_strings	= smsc_get_strings,
427 	.get_stats	= smsc_get_stats,
428 
429 	.suspend	= genphy_suspend,
430 	.resume		= genphy_resume,
431 }, {
432 	.phy_id		= 0x0007c110,
433 	.phy_id_mask	= 0xfffffff0,
434 	.name		= "SMSC LAN8740",
435 
436 	/* PHY_BASIC_FEATURES */
437 	.flags		= PHY_RST_AFTER_CLK_EN,
438 
439 	.probe		= smsc_phy_probe,
440 
441 	/* basic functions */
442 	.read_status	= lan87xx_read_status,
443 	.config_init	= smsc_phy_config_init,
444 	.soft_reset	= smsc_phy_reset,
445 
446 	/* IRQ related */
447 	.config_intr	= smsc_phy_config_intr,
448 	.handle_interrupt = smsc_phy_handle_interrupt,
449 
450 	/* Statistics */
451 	.get_sset_count = smsc_get_sset_count,
452 	.get_strings	= smsc_get_strings,
453 	.get_stats	= smsc_get_stats,
454 
455 	.suspend	= genphy_suspend,
456 	.resume		= genphy_resume,
457 }, {
458 	.phy_id		= 0x0007c130,	/* 0x0007c130 and 0x0007c131 */
459 	/* This mask (0xfffffff2) is to differentiate from
460 	 * LAN88xx (phy_id 0x0007c132)
461 	 * and allows future phy_id revisions.
462 	 */
463 	.phy_id_mask	= 0xfffffff2,
464 	.name		= "Microchip LAN8742",
465 
466 	/* PHY_BASIC_FEATURES */
467 	.flags		= PHY_RST_AFTER_CLK_EN,
468 
469 	.probe		= smsc_phy_probe,
470 
471 	/* basic functions */
472 	.read_status	= lan87xx_read_status,
473 	.config_init	= smsc_phy_config_init,
474 	.soft_reset	= smsc_phy_reset,
475 
476 	/* IRQ related */
477 	.config_intr	= smsc_phy_config_intr,
478 	.handle_interrupt = smsc_phy_handle_interrupt,
479 
480 	/* Statistics */
481 	.get_sset_count = smsc_get_sset_count,
482 	.get_strings	= smsc_get_strings,
483 	.get_stats	= smsc_get_stats,
484 
485 	.suspend	= genphy_suspend,
486 	.resume		= genphy_resume,
487 } };
488 
489 module_phy_driver(smsc_phy_driver);
490 
491 MODULE_DESCRIPTION("SMSC PHY driver");
492 MODULE_AUTHOR("Herbert Valerio Riedel");
493 MODULE_LICENSE("GPL");
494 
495 static struct mdio_device_id __maybe_unused smsc_tbl[] = {
496 	{ 0x0007c0a0, 0xfffffff0 },
497 	{ 0x0007c0b0, 0xfffffff0 },
498 	{ 0x0007c0c0, 0xfffffff0 },
499 	{ 0x0007c0d0, 0xfffffff0 },
500 	{ 0x0007c0f0, 0xfffffff0 },
501 	{ 0x0007c110, 0xfffffff0 },
502 	{ 0x0007c130, 0xfffffff2 },
503 	{ }
504 };
505 
506 MODULE_DEVICE_TABLE(mdio, smsc_tbl);
507