drivers/net/phy/lxt.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * drivers/net/phy/lxt.c
   4  *
   5  * Driver for Intel LXT PHYs
   6  *
   7  * Author: Andy Fleming
   8  *
   9  * Copyright (c) 2004 Freescale Semiconductor, Inc.
  10  */
  11 #include <linux/kernel.h>
  12 #include <linux/string.h>
  13 #include <linux/errno.h>
  14 #include <linux/unistd.h>
  15 #include <linux/interrupt.h>
  16 #include <linux/init.h>
  17 #include <linux/delay.h>
  18 #include <linux/netdevice.h>
  19 #include <linux/etherdevice.h>
  20 #include <linux/skbuff.h>
  21 #include <linux/spinlock.h>
  22 #include <linux/mm.h>
  23 #include <linux/module.h>
  24 #include <linux/mii.h>
  25 #include <linux/ethtool.h>
  26 #include <linux/phy.h>
  27
  28 #include <asm/io.h>
  29 #include <asm/irq.h>
  30 #include <linux/uaccess.h>
  31
  32 /* The Level one LXT970 is used by many boards                               */
  33
  34 #define MII_LXT970_IER       17  /* Interrupt Enable Register */
  35
  36 #define MII_LXT970_IER_IEN      0x0002
  37
  38 #define MII_LXT970_ISR       18  /* Interrupt Status Register */
  39
  40 #define MII_LXT970_CONFIG    19  /* Configuration Register    */
  41
  42 /* ------------------------------------------------------------------------- */
  43 /* The Level one LXT971 is used on some of my custom boards                  */
  44
  45 /* register definitions for the 971 */
  46 #define MII_LXT971_IER          18  /* Interrupt Enable Register */
  47 #define MII_LXT971_IER_IEN      0x00f2
  48
  49 #define MII_LXT971_ISR          19  /* Interrupt Status Register */
  50
  51 /* register definitions for the 973 */
  52 #define MII_LXT973_PCR 16 /* Port Configuration Register */
  53 #define PCR_FIBER_SELECT 1
  54
  55 MODULE_DESCRIPTION("Intel LXT PHY driver");
  56 MODULE_AUTHOR("Andy Fleming");
  57 MODULE_LICENSE("GPL");
  58
  59 static int lxt970_ack_interrupt(struct phy_device *phydev)
  60 {
  61         int err;
  62
  63         err = phy_read(phydev, MII_BMSR);
  64
  65         if (err < 0)
  66                 return err;
  67
  68         err = phy_read(phydev, MII_LXT970_ISR);
  69
  70         if (err < 0)
  71                 return err;
  72
  73         return 0;
  74 }
  75
  76 static int lxt970_config_intr(struct phy_device *phydev)
  77 {
  78         if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
  79                 return phy_write(phydev, MII_LXT970_IER, MII_LXT970_IER_IEN);
  80         else
  81                 return phy_write(phydev, MII_LXT970_IER, 0);
  82 }
  83
  84 static int lxt970_config_init(struct phy_device *phydev)
  85 {
  86         return phy_write(phydev, MII_LXT970_CONFIG, 0);
  87 }
  88
  89
  90 static int lxt971_ack_interrupt(struct phy_device *phydev)
  91 {
  92         int err = phy_read(phydev, MII_LXT971_ISR);
  93
  94         if (err < 0)
  95                 return err;
  96
  97         return 0;
  98 }
  99
 100 static int lxt971_config_intr(struct phy_device *phydev)
 101 {
 102         if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
 103                 return phy_write(phydev, MII_LXT971_IER, MII_LXT971_IER_IEN);
 104         else
 105                 return phy_write(phydev, MII_LXT971_IER, 0);
 106 }
 107
 108 /*
 109  * A2 version of LXT973 chip has an ERRATA: it randomly return the contents
 110  * of the previous even register when you read a odd register regularly
 111  */
 112
 113 static int lxt973a2_update_link(struct phy_device *phydev)
 114 {
 115         int status;
 116         int control;
 117         int retry = 8; /* we try 8 times */
 118
 119         /* Do a fake read */
 120         status = phy_read(phydev, MII_BMSR);
 121
 122         if (status < 0)
 123                 return status;
 124
 125         control = phy_read(phydev, MII_BMCR);
 126         if (control < 0)
 127                 return control;
 128
 129         do {
 130                 /* Read link and autonegotiation status */
 131                 status = phy_read(phydev, MII_BMSR);
 132         } while (status >= 0 && retry-- && status == control);
 133
 134         if (status < 0)
 135                 return status;
 136
 137         if ((status & BMSR_LSTATUS) == 0)
 138                 phydev->link = 0;
 139         else
 140                 phydev->link = 1;
 141
 142         return 0;
 143 }
 144
 145 static int lxt973a2_read_status(struct phy_device *phydev)
 146 {
 147         int adv;
 148         int err;
 149         int lpa;
 150
 151         /* Update the link, but return if there was an error */
 152         err = lxt973a2_update_link(phydev);
 153         if (err)
 154                 return err;
 155
 156         if (AUTONEG_ENABLE == phydev->autoneg) {
 157                 int retry = 1;
 158
 159                 adv = phy_read(phydev, MII_ADVERTISE);
 160
 161                 if (adv < 0)
 162                         return adv;
 163
 164                 do {
 165                         lpa = phy_read(phydev, MII_LPA);
 166
 167                         if (lpa < 0)
 168                                 return lpa;
 169
 170                         /* If both registers are equal, it is suspect but not
 171                         * impossible, hence a new try
 172                         */
 173                 } while (lpa == adv && retry--);
 174
 175                 mii_lpa_to_linkmode_lpa_t(phydev->lp_advertising, lpa);
 176
 177                 lpa &= adv;
 178
 179                 phydev->speed = SPEED_10;
 180                 phydev->duplex = DUPLEX_HALF;
 181                 phydev->pause = phydev->asym_pause = 0;
 182
 183                 if (lpa & (LPA_100FULL | LPA_100HALF)) {
 184                         phydev->speed = SPEED_100;
 185
 186                         if (lpa & LPA_100FULL)
 187                                 phydev->duplex = DUPLEX_FULL;
 188                 } else {
 189                         if (lpa & LPA_10FULL)
 190                                 phydev->duplex = DUPLEX_FULL;
 191                 }
 192
 193                 phy_resolve_aneg_pause(phydev);
 194         } else {
 195                 err = genphy_read_status_fixed(phydev);
 196                 if (err < 0)
 197                         return err;
 198
 199                 phydev->pause = phydev->asym_pause = 0;
 200                 linkmode_zero(phydev->lp_advertising);
 201         }
 202
 203         return 0;
 204 }
 205
 206 static int lxt973_probe(struct phy_device *phydev)
 207 {
 208         int val = phy_read(phydev, MII_LXT973_PCR);
 209
 210         if (val & PCR_FIBER_SELECT) {
 211                 /*
 212                  * If fiber is selected, then the only correct setting
 213                  * is 100Mbps, full duplex, and auto negotiation off.
 214                  */
 215                 val = phy_read(phydev, MII_BMCR);
 216                 val |= (BMCR_SPEED100 | BMCR_FULLDPLX);
 217                 val &= ~BMCR_ANENABLE;
 218                 phy_write(phydev, MII_BMCR, val);
 219                 /* Remember that the port is in fiber mode. */
 220                 phydev->priv = lxt973_probe;
 221         } else {
 222                 phydev->priv = NULL;
 223         }
 224         return 0;
 225 }
 226
 227 static int lxt973_config_aneg(struct phy_device *phydev)
 228 {
 229         /* Do nothing if port is in fiber mode. */
 230         return phydev->priv ? 0 : genphy_config_aneg(phydev);
 231 }
 232
 233 static struct phy_driver lxt97x_driver[] = {
 234 {
 235         .phy_id         = 0x78100000,
 236         .name           = "LXT970",
 237         .phy_id_mask    = 0xfffffff0,
 238         /* PHY_BASIC_FEATURES */
 239         .config_init    = lxt970_config_init,
 240         .ack_interrupt  = lxt970_ack_interrupt,
 241         .config_intr    = lxt970_config_intr,
 242 }, {
 243         .phy_id         = 0x001378e0,
 244         .name           = "LXT971",
 245         .phy_id_mask    = 0xfffffff0,
 246         /* PHY_BASIC_FEATURES */
 247         .ack_interrupt  = lxt971_ack_interrupt,
 248         .config_intr    = lxt971_config_intr,
 249         .suspend        = genphy_suspend,
 250         .resume         = genphy_resume,
 251 }, {
 252         .phy_id         = 0x00137a10,
 253         .name           = "LXT973-A2",
 254         .phy_id_mask    = 0xffffffff,
 255         /* PHY_BASIC_FEATURES */
 256         .flags          = 0,
 257         .probe          = lxt973_probe,
 258         .config_aneg    = lxt973_config_aneg,
 259         .read_status    = lxt973a2_read_status,
 260         .suspend        = genphy_suspend,
 261         .resume         = genphy_resume,
 262 }, {
 263         .phy_id         = 0x00137a10,
 264         .name           = "LXT973",
 265         .phy_id_mask    = 0xfffffff0,
 266         /* PHY_BASIC_FEATURES */
 267         .flags          = 0,
 268         .probe          = lxt973_probe,
 269         .config_aneg    = lxt973_config_aneg,
 270         .suspend        = genphy_suspend,
 271         .resume         = genphy_resume,
 272 } };
 273
 274 module_phy_driver(lxt97x_driver);
 275
 276 static struct mdio_device_id __maybe_unused lxt_tbl[] = {
 277         { 0x78100000, 0xfffffff0 },
 278         { 0x001378e0, 0xfffffff0 },
 279         { 0x00137a10, 0xfffffff0 },
 280         { }
 281 };
 282
 283 MODULE_DEVICE_TABLE(mdio, lxt_tbl);