xref: /openbmc/linux/drivers/net/phy/lxt.c (revision 8a10bc9d)
1 /*
2  * drivers/net/phy/lxt.c
3  *
4  * Driver for Intel LXT PHYs
5  *
6  * Author: Andy Fleming
7  *
8  * Copyright (c) 2004 Freescale Semiconductor, Inc.
9  *
10  * This program is free software; you can redistribute  it and/or modify it
11  * under  the terms of  the GNU General  Public License as published by the
12  * Free Software Foundation;  either version 2 of the  License, or (at your
13  * option) any later version.
14  *
15  */
16 #include <linux/kernel.h>
17 #include <linux/string.h>
18 #include <linux/errno.h>
19 #include <linux/unistd.h>
20 #include <linux/interrupt.h>
21 #include <linux/init.h>
22 #include <linux/delay.h>
23 #include <linux/netdevice.h>
24 #include <linux/etherdevice.h>
25 #include <linux/skbuff.h>
26 #include <linux/spinlock.h>
27 #include <linux/mm.h>
28 #include <linux/module.h>
29 #include <linux/mii.h>
30 #include <linux/ethtool.h>
31 #include <linux/phy.h>
32 
33 #include <asm/io.h>
34 #include <asm/irq.h>
35 #include <asm/uaccess.h>
36 
37 /* The Level one LXT970 is used by many boards				     */
38 
39 #define MII_LXT970_IER       17  /* Interrupt Enable Register */
40 
41 #define MII_LXT970_IER_IEN	0x0002
42 
43 #define MII_LXT970_ISR       18  /* Interrupt Status Register */
44 
45 #define MII_LXT970_CONFIG    19  /* Configuration Register    */
46 
47 /* ------------------------------------------------------------------------- */
48 /* The Level one LXT971 is used on some of my custom boards                  */
49 
50 /* register definitions for the 971 */
51 #define MII_LXT971_IER		18  /* Interrupt Enable Register */
52 #define MII_LXT971_IER_IEN	0x00f2
53 
54 #define MII_LXT971_ISR		19  /* Interrupt Status Register */
55 
56 /* register definitions for the 973 */
57 #define MII_LXT973_PCR 16 /* Port Configuration Register */
58 #define PCR_FIBER_SELECT 1
59 
60 MODULE_DESCRIPTION("Intel LXT PHY driver");
61 MODULE_AUTHOR("Andy Fleming");
62 MODULE_LICENSE("GPL");
63 
64 static int lxt970_ack_interrupt(struct phy_device *phydev)
65 {
66 	int err;
67 
68 	err = phy_read(phydev, MII_BMSR);
69 
70 	if (err < 0)
71 		return err;
72 
73 	err = phy_read(phydev, MII_LXT970_ISR);
74 
75 	if (err < 0)
76 		return err;
77 
78 	return 0;
79 }
80 
81 static int lxt970_config_intr(struct phy_device *phydev)
82 {
83 	int err;
84 
85 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
86 		err = phy_write(phydev, MII_LXT970_IER, MII_LXT970_IER_IEN);
87 	else
88 		err = phy_write(phydev, MII_LXT970_IER, 0);
89 
90 	return err;
91 }
92 
93 static int lxt970_config_init(struct phy_device *phydev)
94 {
95 	int err;
96 
97 	err = phy_write(phydev, MII_LXT970_CONFIG, 0);
98 
99 	return err;
100 }
101 
102 
103 static int lxt971_ack_interrupt(struct phy_device *phydev)
104 {
105 	int err = phy_read(phydev, MII_LXT971_ISR);
106 
107 	if (err < 0)
108 		return err;
109 
110 	return 0;
111 }
112 
113 static int lxt971_config_intr(struct phy_device *phydev)
114 {
115 	int err;
116 
117 	if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
118 		err = phy_write(phydev, MII_LXT971_IER, MII_LXT971_IER_IEN);
119 	else
120 		err = phy_write(phydev, MII_LXT971_IER, 0);
121 
122 	return err;
123 }
124 
125 /*
126  * A2 version of LXT973 chip has an ERRATA: it randomly return the contents
127  * of the previous even register when you read a odd register regularly
128  */
129 
130 static int lxt973a2_update_link(struct phy_device *phydev)
131 {
132 	int status;
133 	int control;
134 	int retry = 8; /* we try 8 times */
135 
136 	/* Do a fake read */
137 	status = phy_read(phydev, MII_BMSR);
138 
139 	if (status < 0)
140 		return status;
141 
142 	control = phy_read(phydev, MII_BMCR);
143 	if (control < 0)
144 		return control;
145 
146 	do {
147 		/* Read link and autonegotiation status */
148 		status = phy_read(phydev, MII_BMSR);
149 	} while (status >= 0 && retry-- && status == control);
150 
151 	if (status < 0)
152 		return status;
153 
154 	if ((status & BMSR_LSTATUS) == 0)
155 		phydev->link = 0;
156 	else
157 		phydev->link = 1;
158 
159 	return 0;
160 }
161 
162 static int lxt973a2_read_status(struct phy_device *phydev)
163 {
164 	int adv;
165 	int err;
166 	int lpa;
167 	int lpagb = 0;
168 
169 	/* Update the link, but return if there was an error */
170 	err = lxt973a2_update_link(phydev);
171 	if (err)
172 		return err;
173 
174 	if (AUTONEG_ENABLE == phydev->autoneg) {
175 		int retry = 1;
176 
177 		adv = phy_read(phydev, MII_ADVERTISE);
178 
179 		if (adv < 0)
180 			return adv;
181 
182 		do {
183 			lpa = phy_read(phydev, MII_LPA);
184 
185 			if (lpa < 0)
186 				return lpa;
187 
188 			/* If both registers are equal, it is suspect but not
189 			* impossible, hence a new try
190 			*/
191 		} while (lpa == adv && retry--);
192 
193 		lpa &= adv;
194 
195 		phydev->speed = SPEED_10;
196 		phydev->duplex = DUPLEX_HALF;
197 		phydev->pause = phydev->asym_pause = 0;
198 
199 		if (lpagb & (LPA_1000FULL | LPA_1000HALF)) {
200 			phydev->speed = SPEED_1000;
201 
202 			if (lpagb & LPA_1000FULL)
203 				phydev->duplex = DUPLEX_FULL;
204 		} else if (lpa & (LPA_100FULL | LPA_100HALF)) {
205 			phydev->speed = SPEED_100;
206 
207 			if (lpa & LPA_100FULL)
208 				phydev->duplex = DUPLEX_FULL;
209 		} else {
210 			if (lpa & LPA_10FULL)
211 				phydev->duplex = DUPLEX_FULL;
212 		}
213 
214 		if (phydev->duplex == DUPLEX_FULL) {
215 			phydev->pause = lpa & LPA_PAUSE_CAP ? 1 : 0;
216 			phydev->asym_pause = lpa & LPA_PAUSE_ASYM ? 1 : 0;
217 		}
218 	} else {
219 		int bmcr = phy_read(phydev, MII_BMCR);
220 
221 		if (bmcr < 0)
222 			return bmcr;
223 
224 		if (bmcr & BMCR_FULLDPLX)
225 			phydev->duplex = DUPLEX_FULL;
226 		else
227 			phydev->duplex = DUPLEX_HALF;
228 
229 		if (bmcr & BMCR_SPEED1000)
230 			phydev->speed = SPEED_1000;
231 		else if (bmcr & BMCR_SPEED100)
232 			phydev->speed = SPEED_100;
233 		else
234 			phydev->speed = SPEED_10;
235 
236 		phydev->pause = phydev->asym_pause = 0;
237 	}
238 
239 	return 0;
240 }
241 
242 static int lxt973_probe(struct phy_device *phydev)
243 {
244 	int val = phy_read(phydev, MII_LXT973_PCR);
245 
246 	if (val & PCR_FIBER_SELECT) {
247 		/*
248 		 * If fiber is selected, then the only correct setting
249 		 * is 100Mbps, full duplex, and auto negotiation off.
250 		 */
251 		val = phy_read(phydev, MII_BMCR);
252 		val |= (BMCR_SPEED100 | BMCR_FULLDPLX);
253 		val &= ~BMCR_ANENABLE;
254 		phy_write(phydev, MII_BMCR, val);
255 		/* Remember that the port is in fiber mode. */
256 		phydev->priv = lxt973_probe;
257 	} else {
258 		phydev->priv = NULL;
259 	}
260 	return 0;
261 }
262 
263 static int lxt973_config_aneg(struct phy_device *phydev)
264 {
265 	/* Do nothing if port is in fiber mode. */
266 	return phydev->priv ? 0 : genphy_config_aneg(phydev);
267 }
268 
269 static struct phy_driver lxt97x_driver[] = {
270 {
271 	.phy_id		= 0x78100000,
272 	.name		= "LXT970",
273 	.phy_id_mask	= 0xfffffff0,
274 	.features	= PHY_BASIC_FEATURES,
275 	.flags		= PHY_HAS_INTERRUPT,
276 	.config_init	= lxt970_config_init,
277 	.config_aneg	= genphy_config_aneg,
278 	.read_status	= genphy_read_status,
279 	.ack_interrupt	= lxt970_ack_interrupt,
280 	.config_intr	= lxt970_config_intr,
281 	.driver		= { .owner = THIS_MODULE,},
282 }, {
283 	.phy_id		= 0x001378e0,
284 	.name		= "LXT971",
285 	.phy_id_mask	= 0xfffffff0,
286 	.features	= PHY_BASIC_FEATURES,
287 	.flags		= PHY_HAS_INTERRUPT,
288 	.config_aneg	= genphy_config_aneg,
289 	.read_status	= genphy_read_status,
290 	.ack_interrupt	= lxt971_ack_interrupt,
291 	.config_intr	= lxt971_config_intr,
292 	.driver		= { .owner = THIS_MODULE,},
293 }, {
294 	.phy_id		= 0x00137a10,
295 	.name		= "LXT973-A2",
296 	.phy_id_mask	= 0xffffffff,
297 	.features	= PHY_BASIC_FEATURES,
298 	.flags		= 0,
299 	.probe		= lxt973_probe,
300 	.config_aneg	= lxt973_config_aneg,
301 	.read_status	= lxt973a2_read_status,
302 	.driver		= { .owner = THIS_MODULE,},
303 }, {
304 	.phy_id		= 0x00137a10,
305 	.name		= "LXT973",
306 	.phy_id_mask	= 0xfffffff0,
307 	.features	= PHY_BASIC_FEATURES,
308 	.flags		= 0,
309 	.probe		= lxt973_probe,
310 	.config_aneg	= lxt973_config_aneg,
311 	.read_status	= genphy_read_status,
312 	.driver		= { .owner = THIS_MODULE,},
313 } };
314 
315 static int __init lxt_init(void)
316 {
317 	return phy_drivers_register(lxt97x_driver,
318 		ARRAY_SIZE(lxt97x_driver));
319 }
320 
321 static void __exit lxt_exit(void)
322 {
323 	phy_drivers_unregister(lxt97x_driver,
324 		ARRAY_SIZE(lxt97x_driver));
325 }
326 
327 module_init(lxt_init);
328 module_exit(lxt_exit);
329 
330 static struct mdio_device_id __maybe_unused lxt_tbl[] = {
331 	{ 0x78100000, 0xfffffff0 },
332 	{ 0x001378e0, 0xfffffff0 },
333 	{ 0x00137a10, 0xfffffff0 },
334 	{ }
335 };
336 
337 MODULE_DEVICE_TABLE(mdio, lxt_tbl);
338