drivers/net/phy/phy.c

   1 /*
   2  * drivers/net/phy/phy.c
   3  *
   4  * Framework for configuring and reading PHY devices
   5  * Based on code in sungem_phy.c and gianfar_phy.c
   6  *
   7  * Author: Andy Fleming
   8  *
   9  * Copyright (c) 2004 Freescale Semiconductor, Inc.
  10  *
  11  * This program is free software; you can redistribute  it and/or modify it
  12  * under  the terms of  the GNU General  Public License as published by the
  13  * Free Software Foundation;  either version 2 of the  License, or (at your
  14  * option) any later version.
  15  *
  16  */
  17 #include <linux/config.h>
  18 #include <linux/kernel.h>
  19 #include <linux/sched.h>
  20 #include <linux/string.h>
  21 #include <linux/errno.h>
  22 #include <linux/unistd.h>
  23 #include <linux/slab.h>
  24 #include <linux/interrupt.h>
  25 #include <linux/init.h>
  26 #include <linux/delay.h>
  27 #include <linux/netdevice.h>
  28 #include <linux/etherdevice.h>
  29 #include <linux/skbuff.h>
  30 #include <linux/spinlock.h>
  31 #include <linux/mm.h>
  32 #include <linux/module.h>
  33 #include <linux/mii.h>
  34 #include <linux/ethtool.h>
  35 #include <linux/phy.h>
  36
  37 #include <asm/io.h>
  38 #include <asm/irq.h>
  39 #include <asm/uaccess.h>
  40
  41 /* Convenience function to print out the current phy status
  42  */
  43 void phy_print_status(struct phy_device *phydev)
  44 {
  45         pr_info("PHY: %s - Link is %s", phydev->dev.bus_id,
  46                         phydev->link ? "Up" : "Down");
  47         if (phydev->link)
  48                 printk(" - %d/%s", phydev->speed,
  49                                 DUPLEX_FULL == phydev->duplex ?
  50                                 "Full" : "Half");
  51
  52         printk("\n");
  53 }
  54 EXPORT_SYMBOL(phy_print_status);
  55
  56
  57 /* Convenience functions for reading/writing a given PHY
  58  * register. They MUST NOT be called from interrupt context,
  59  * because the bus read/write functions may wait for an interrupt
  60  * to conclude the operation. */
  61 int phy_read(struct phy_device *phydev, u16 regnum)
  62 {
  63         int retval;
  64         struct mii_bus *bus = phydev->bus;
  65
  66         spin_lock_bh(&bus->mdio_lock);
  67         retval = bus->read(bus, phydev->addr, regnum);
  68         spin_unlock_bh(&bus->mdio_lock);
  69
  70         return retval;
  71 }
  72 EXPORT_SYMBOL(phy_read);
  73
  74 int phy_write(struct phy_device *phydev, u16 regnum, u16 val)
  75 {
  76         int err;
  77         struct mii_bus *bus = phydev->bus;
  78
  79         spin_lock_bh(&bus->mdio_lock);
  80         err = bus->write(bus, phydev->addr, regnum, val);
  81         spin_unlock_bh(&bus->mdio_lock);
  82
  83         return err;
  84 }
  85 EXPORT_SYMBOL(phy_write);
  86
  87
  88 int phy_clear_interrupt(struct phy_device *phydev)
  89 {
  90         int err = 0;
  91
  92         if (phydev->drv->ack_interrupt)
  93                 err = phydev->drv->ack_interrupt(phydev);
  94
  95         return err;
  96 }
  97
  98
  99 int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
 100 {
 101         int err = 0;
 102
 103         phydev->interrupts = interrupts;
 104         if (phydev->drv->config_intr)
 105                 err = phydev->drv->config_intr(phydev);
 106
 107         return err;
 108 }
 109
 110
 111 /* phy_aneg_done
 112  *
 113  * description: Reads the status register and returns 0 either if
 114  *   auto-negotiation is incomplete, or if there was an error.
 115  *   Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
 116  */
 117 static inline int phy_aneg_done(struct phy_device *phydev)
 118 {
 119         int retval;
 120
 121         retval = phy_read(phydev, MII_BMSR);
 122
 123         return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
 124 }
 125
 126 /* A structure for mapping a particular speed and duplex
 127  * combination to a particular SUPPORTED and ADVERTISED value */
 128 struct phy_setting {
 129         int speed;
 130         int duplex;
 131         u32 setting;
 132 };
 133
 134 /* A mapping of all SUPPORTED settings to speed/duplex */
 135 static const struct phy_setting settings[] = {
 136         {
 137                 .speed = 10000,
 138                 .duplex = DUPLEX_FULL,
 139                 .setting = SUPPORTED_10000baseT_Full,
 140         },
 141         {
 142                 .speed = SPEED_1000,
 143                 .duplex = DUPLEX_FULL,
 144                 .setting = SUPPORTED_1000baseT_Full,
 145         },
 146         {
 147                 .speed = SPEED_1000,
 148                 .duplex = DUPLEX_HALF,
 149                 .setting = SUPPORTED_1000baseT_Half,
 150         },
 151         {
 152                 .speed = SPEED_100,
 153                 .duplex = DUPLEX_FULL,
 154                 .setting = SUPPORTED_100baseT_Full,
 155         },
 156         {
 157                 .speed = SPEED_100,
 158                 .duplex = DUPLEX_HALF,
 159                 .setting = SUPPORTED_100baseT_Half,
 160         },
 161         {
 162                 .speed = SPEED_10,
 163                 .duplex = DUPLEX_FULL,
 164                 .setting = SUPPORTED_10baseT_Full,
 165         },
 166         {
 167                 .speed = SPEED_10,
 168                 .duplex = DUPLEX_HALF,
 169                 .setting = SUPPORTED_10baseT_Half,
 170         },
 171 };
 172
 173 #define MAX_NUM_SETTINGS (sizeof(settings)/sizeof(struct phy_setting))
 174
 175 /* phy_find_setting
 176  *
 177  * description: Searches the settings array for the setting which
 178  *   matches the desired speed and duplex, and returns the index
 179  *   of that setting.  Returns the index of the last setting if
 180  *   none of the others match.
 181  */
 182 static inline int phy_find_setting(int speed, int duplex)
 183 {
 184         int idx = 0;
 185
 186         while (idx < ARRAY_SIZE(settings) &&
 187                         (settings[idx].speed != speed ||
 188                         settings[idx].duplex != duplex))
 189                 idx++;
 190
 191         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
 192 }
 193
 194 /* phy_find_valid
 195  * idx: The first index in settings[] to search
 196  * features: A mask of the valid settings
 197  *
 198  * description: Returns the index of the first valid setting less
 199  *   than or equal to the one pointed to by idx, as determined by
 200  *   the mask in features.  Returns the index of the last setting
 201  *   if nothing else matches.
 202  */
 203 static inline int phy_find_valid(int idx, u32 features)
 204 {
 205         while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
 206                 idx++;
 207
 208         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
 209 }
 210
 211 /* phy_sanitize_settings
 212  *
 213  * description: Make sure the PHY is set to supported speeds and
 214  *   duplexes.  Drop down by one in this order:  1000/FULL,
 215  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF
 216  */
 217 void phy_sanitize_settings(struct phy_device *phydev)
 218 {
 219         u32 features = phydev->supported;
 220         int idx;
 221
 222         /* Sanitize settings based on PHY capabilities */
 223         if ((features & SUPPORTED_Autoneg) == 0)
 224                 phydev->autoneg = 0;
 225
 226         idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
 227                         features);
 228
 229         phydev->speed = settings[idx].speed;
 230         phydev->duplex = settings[idx].duplex;
 231 }
 232 EXPORT_SYMBOL(phy_sanitize_settings);
 233
 234 /* phy_ethtool_sset:
 235  * A generic ethtool sset function.  Handles all the details
 236  *
 237  * A few notes about parameter checking:
 238  * - We don't set port or transceiver, so we don't care what they
 239  *   were set to.
 240  * - phy_start_aneg() will make sure forced settings are sane, and
 241  *   choose the next best ones from the ones selected, so we don't
 242  *   care if ethtool tries to give us bad values
 243  *
 244  */
 245 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 246 {
 247         if (cmd->phy_address != phydev->addr)
 248                 return -EINVAL;
 249
 250         /* We make sure that we don't pass unsupported
 251          * values in to the PHY */
 252         cmd->advertising &= phydev->supported;
 253
 254         /* Verify the settings we care about. */
 255         if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
 256                 return -EINVAL;
 257
 258         if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
 259                 return -EINVAL;
 260
 261         if (cmd->autoneg == AUTONEG_DISABLE
 262                         && ((cmd->speed != SPEED_1000
 263                                         && cmd->speed != SPEED_100
 264                                         && cmd->speed != SPEED_10)
 265                                 || (cmd->duplex != DUPLEX_HALF
 266                                         && cmd->duplex != DUPLEX_FULL)))
 267                 return -EINVAL;
 268
 269         phydev->autoneg = cmd->autoneg;
 270
 271         phydev->speed = cmd->speed;
 272
 273         phydev->advertising = cmd->advertising;
 274
 275         if (AUTONEG_ENABLE == cmd->autoneg)
 276                 phydev->advertising |= ADVERTISED_Autoneg;
 277         else
 278                 phydev->advertising &= ~ADVERTISED_Autoneg;
 279
 280         phydev->duplex = cmd->duplex;
 281
 282         /* Restart the PHY */
 283         phy_start_aneg(phydev);
 284
 285         return 0;
 286 }
 287
 288 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 289 {
 290         cmd->supported = phydev->supported;
 291
 292         cmd->advertising = phydev->advertising;
 293
 294         cmd->speed = phydev->speed;
 295         cmd->duplex = phydev->duplex;
 296         cmd->port = PORT_MII;
 297         cmd->phy_address = phydev->addr;
 298         cmd->transceiver = XCVR_EXTERNAL;
 299         cmd->autoneg = phydev->autoneg;
 300
 301         return 0;
 302 }
 303
 304
 305 /* Note that this function is currently incompatible with the
 306  * PHYCONTROL layer.  It changes registers without regard to
 307  * current state.  Use at own risk
 308  */
 309 int phy_mii_ioctl(struct phy_device *phydev,
 310                 struct mii_ioctl_data *mii_data, int cmd)
 311 {
 312         u16 val = mii_data->val_in;
 313
 314         switch (cmd) {
 315         case SIOCGMIIPHY:
 316                 mii_data->phy_id = phydev->addr;
 317                 break;
 318         case SIOCGMIIREG:
 319                 mii_data->val_out = phy_read(phydev, mii_data->reg_num);
 320                 break;
 321
 322         case SIOCSMIIREG:
 323                 if (!capable(CAP_NET_ADMIN))
 324                         return -EPERM;
 325
 326                 if (mii_data->phy_id == phydev->addr) {
 327                         switch(mii_data->reg_num) {
 328                         case MII_BMCR:
 329                                 if (val & (BMCR_RESET|BMCR_ANENABLE))
 330                                         phydev->autoneg = AUTONEG_DISABLE;
 331                                 else
 332                                         phydev->autoneg = AUTONEG_ENABLE;
 333                                 if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
 334                                         phydev->duplex = DUPLEX_FULL;
 335                                 else
 336                                         phydev->duplex = DUPLEX_HALF;
 337                                 break;
 338                         case MII_ADVERTISE:
 339                                 phydev->advertising = val;
 340                                 break;
 341                         default:
 342                                 /* do nothing */
 343                                 break;
 344                         }
 345                 }
 346
 347                 phy_write(phydev, mii_data->reg_num, val);
 348
 349                 if (mii_data->reg_num == MII_BMCR
 350                                 && val & BMCR_RESET
 351                                 && phydev->drv->config_init)
 352                         phydev->drv->config_init(phydev);
 353                 break;
 354         }
 355
 356         return 0;
 357 }
 358
 359 /* phy_start_aneg
 360  *
 361  * description: Sanitizes the settings (if we're not
 362  *   autonegotiating them), and then calls the driver's
 363  *   config_aneg function.  If the PHYCONTROL Layer is operating,
 364  *   we change the state to reflect the beginning of
 365  *   Auto-negotiation or forcing.
 366  */
 367 int phy_start_aneg(struct phy_device *phydev)
 368 {
 369         int err;
 370
 371         spin_lock(&phydev->lock);
 372
 373         if (AUTONEG_DISABLE == phydev->autoneg)
 374                 phy_sanitize_settings(phydev);
 375
 376         err = phydev->drv->config_aneg(phydev);
 377
 378         if (err < 0)
 379                 goto out_unlock;
 380
 381         if (phydev->state != PHY_HALTED) {
 382                 if (AUTONEG_ENABLE == phydev->autoneg) {
 383                         phydev->state = PHY_AN;
 384                         phydev->link_timeout = PHY_AN_TIMEOUT;
 385                 } else {
 386                         phydev->state = PHY_FORCING;
 387                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
 388                 }
 389         }
 390
 391 out_unlock:
 392         spin_unlock(&phydev->lock);
 393         return err;
 394 }
 395 EXPORT_SYMBOL(phy_start_aneg);
 396
 397
 398 static void phy_change(void *data);
 399 static void phy_timer(unsigned long data);
 400
 401 /* phy_start_machine:
 402  *
 403  * description: The PHY infrastructure can run a state machine
 404  *   which tracks whether the PHY is starting up, negotiating,
 405  *   etc.  This function starts the timer which tracks the state
 406  *   of the PHY.  If you want to be notified when the state
 407  *   changes, pass in the callback, otherwise, pass NULL.  If you
 408  *   want to maintain your own state machine, do not call this
 409  *   function. */
 410 void phy_start_machine(struct phy_device *phydev,
 411                 void (*handler)(struct net_device *))
 412 {
 413         phydev->adjust_state = handler;
 414
 415         init_timer(&phydev->phy_timer);
 416         phydev->phy_timer.function = &phy_timer;
 417         phydev->phy_timer.data = (unsigned long) phydev;
 418         mod_timer(&phydev->phy_timer, jiffies + HZ);
 419 }
 420
 421 /* phy_stop_machine
 422  *
 423  * description: Stops the state machine timer, sets the state to
 424  *   UP (unless it wasn't up yet), and then frees the interrupt,
 425  *   if it is in use. This function must be called BEFORE
 426  *   phy_detach.
 427  */
 428 void phy_stop_machine(struct phy_device *phydev)
 429 {
 430         del_timer_sync(&phydev->phy_timer);
 431
 432         spin_lock(&phydev->lock);
 433         if (phydev->state > PHY_UP)
 434                 phydev->state = PHY_UP;
 435         spin_unlock(&phydev->lock);
 436
 437         if (phydev->irq != PHY_POLL)
 438                 phy_stop_interrupts(phydev);
 439
 440         phydev->adjust_state = NULL;
 441 }
 442
 443 /* phy_force_reduction
 444  *
 445  * description: Reduces the speed/duplex settings by
 446  *   one notch.  The order is so:
 447  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF,
 448  *   10/FULL, 10/HALF.  The function bottoms out at 10/HALF.
 449  */
 450 static void phy_force_reduction(struct phy_device *phydev)
 451 {
 452         int idx;
 453
 454         idx = phy_find_setting(phydev->speed, phydev->duplex);
 455
 456         idx++;
 457
 458         idx = phy_find_valid(idx, phydev->supported);
 459
 460         phydev->speed = settings[idx].speed;
 461         phydev->duplex = settings[idx].duplex;
 462
 463         pr_info("Trying %d/%s\n", phydev->speed,
 464                         DUPLEX_FULL == phydev->duplex ?
 465                         "FULL" : "HALF");
 466 }
 467
 468
 469 /* phy_error:
 470  *
 471  * Moves the PHY to the HALTED state in response to a read
 472  * or write error, and tells the controller the link is down.
 473  * Must not be called from interrupt context, or while the
 474  * phydev->lock is held.
 475  */
 476 void phy_error(struct phy_device *phydev)
 477 {
 478         spin_lock(&phydev->lock);
 479         phydev->state = PHY_HALTED;
 480         spin_unlock(&phydev->lock);
 481 }
 482
 483 /* phy_interrupt
 484  *
 485  * description: When a PHY interrupt occurs, the handler disables
 486  * interrupts, and schedules a work task to clear the interrupt.
 487  */
 488 static irqreturn_t phy_interrupt(int irq, void *phy_dat, struct pt_regs *regs)
 489 {
 490         struct phy_device *phydev = phy_dat;
 491
 492         /* The MDIO bus is not allowed to be written in interrupt
 493          * context, so we need to disable the irq here.  A work
 494          * queue will write the PHY to disable and clear the
 495          * interrupt, and then reenable the irq line. */
 496         disable_irq_nosync(irq);
 497
 498         schedule_work(&phydev->phy_queue);
 499
 500         return IRQ_HANDLED;
 501 }
 502
 503 /* Enable the interrupts from the PHY side */
 504 int phy_enable_interrupts(struct phy_device *phydev)
 505 {
 506         int err;
 507
 508         err = phy_clear_interrupt(phydev);
 509
 510         if (err < 0)
 511                 return err;
 512
 513         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 514
 515         return err;
 516 }
 517 EXPORT_SYMBOL(phy_enable_interrupts);
 518
 519 /* Disable the PHY interrupts from the PHY side */
 520 int phy_disable_interrupts(struct phy_device *phydev)
 521 {
 522         int err;
 523
 524         /* Disable PHY interrupts */
 525         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 526
 527         if (err)
 528                 goto phy_err;
 529
 530         /* Clear the interrupt */
 531         err = phy_clear_interrupt(phydev);
 532
 533         if (err)
 534                 goto phy_err;
 535
 536         return 0;
 537
 538 phy_err:
 539         phy_error(phydev);
 540
 541         return err;
 542 }
 543 EXPORT_SYMBOL(phy_disable_interrupts);
 544
 545 /* phy_start_interrupts
 546  *
 547  * description: Request the interrupt for the given PHY.  If
 548  *   this fails, then we set irq to PHY_POLL.
 549  *   Otherwise, we enable the interrupts in the PHY.
 550  *   Returns 0 on success.
 551  *   This should only be called with a valid IRQ number.
 552  */
 553 int phy_start_interrupts(struct phy_device *phydev)
 554 {
 555         int err = 0;
 556
 557         INIT_WORK(&phydev->phy_queue, phy_change, phydev);
 558
 559         if (request_irq(phydev->irq, phy_interrupt,
 560                                 SA_SHIRQ,
 561                                 "phy_interrupt",
 562                                 phydev) < 0) {
 563                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 564                                 phydev->bus->name,
 565                                 phydev->irq);
 566                 phydev->irq = PHY_POLL;
 567                 return 0;
 568         }
 569
 570         err = phy_enable_interrupts(phydev);
 571
 572         return err;
 573 }
 574 EXPORT_SYMBOL(phy_start_interrupts);
 575
 576 int phy_stop_interrupts(struct phy_device *phydev)
 577 {
 578         int err;
 579
 580         err = phy_disable_interrupts(phydev);
 581
 582         if (err)
 583                 phy_error(phydev);
 584
 585         free_irq(phydev->irq, phydev);
 586
 587         return err;
 588 }
 589 EXPORT_SYMBOL(phy_stop_interrupts);
 590
 591
 592 /* Scheduled by the phy_interrupt/timer to handle PHY changes */
 593 static void phy_change(void *data)
 594 {
 595         int err;
 596         struct phy_device *phydev = data;
 597
 598         err = phy_disable_interrupts(phydev);
 599
 600         if (err)
 601                 goto phy_err;
 602
 603         spin_lock(&phydev->lock);
 604         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 605                 phydev->state = PHY_CHANGELINK;
 606         spin_unlock(&phydev->lock);
 607
 608         enable_irq(phydev->irq);
 609
 610         /* Reenable interrupts */
 611         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 612
 613         if (err)
 614                 goto irq_enable_err;
 615
 616         return;
 617
 618 irq_enable_err:
 619         disable_irq(phydev->irq);
 620 phy_err:
 621         phy_error(phydev);
 622 }
 623
 624 /* Bring down the PHY link, and stop checking the status. */
 625 void phy_stop(struct phy_device *phydev)
 626 {
 627         spin_lock(&phydev->lock);
 628
 629         if (PHY_HALTED == phydev->state)
 630                 goto out_unlock;
 631
 632         if (phydev->irq != PHY_POLL) {
 633                 /* Clear any pending interrupts */
 634                 phy_clear_interrupt(phydev);
 635
 636                 /* Disable PHY Interrupts */
 637                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 638         }
 639
 640         phydev->state = PHY_HALTED;
 641
 642 out_unlock:
 643         spin_unlock(&phydev->lock);
 644 }
 645
 646
 647 /* phy_start
 648  *
 649  * description: Indicates the attached device's readiness to
 650  *   handle PHY-related work.  Used during startup to start the
 651  *   PHY, and after a call to phy_stop() to resume operation.
 652  *   Also used to indicate the MDIO bus has cleared an error
 653  *   condition.
 654  */
 655 void phy_start(struct phy_device *phydev)
 656 {
 657         spin_lock(&phydev->lock);
 658
 659         switch (phydev->state) {
 660                 case PHY_STARTING:
 661                         phydev->state = PHY_PENDING;
 662                         break;
 663                 case PHY_READY:
 664                         phydev->state = PHY_UP;
 665                         break;
 666                 case PHY_HALTED:
 667                         phydev->state = PHY_RESUMING;
 668                 default:
 669                         break;
 670         }
 671         spin_unlock(&phydev->lock);
 672 }
 673 EXPORT_SYMBOL(phy_stop);
 674 EXPORT_SYMBOL(phy_start);
 675
 676 /* PHY timer which handles the state machine */
 677 static void phy_timer(unsigned long data)
 678 {
 679         struct phy_device *phydev = (struct phy_device *)data;
 680         int needs_aneg = 0;
 681         int err = 0;
 682
 683         spin_lock(&phydev->lock);
 684
 685         if (phydev->adjust_state)
 686                 phydev->adjust_state(phydev->attached_dev);
 687
 688         switch(phydev->state) {
 689                 case PHY_DOWN:
 690                 case PHY_STARTING:
 691                 case PHY_READY:
 692                 case PHY_PENDING:
 693                         break;
 694                 case PHY_UP:
 695                         needs_aneg = 1;
 696
 697                         phydev->link_timeout = PHY_AN_TIMEOUT;
 698
 699                         break;
 700                 case PHY_AN:
 701                         /* Check if negotiation is done.  Break
 702                          * if there's an error */
 703                         err = phy_aneg_done(phydev);
 704                         if (err < 0)
 705                                 break;
 706
 707                         /* If auto-negotiation is done, we change to
 708                          * either RUNNING, or NOLINK */
 709                         if (err > 0) {
 710                                 err = phy_read_status(phydev);
 711
 712                                 if (err)
 713                                         break;
 714
 715                                 if (phydev->link) {
 716                                         phydev->state = PHY_RUNNING;
 717                                         netif_carrier_on(phydev->attached_dev);
 718                                 } else {
 719                                         phydev->state = PHY_NOLINK;
 720                                         netif_carrier_off(phydev->attached_dev);
 721                                 }
 722
 723                                 phydev->adjust_link(phydev->attached_dev);
 724
 725                         } else if (0 == phydev->link_timeout--) {
 726                                 /* The counter expired, so either we
 727                                  * switch to forced mode, or the
 728                                  * magic_aneg bit exists, and we try aneg
 729                                  * again */
 730                                 if (!(phydev->drv->flags & PHY_HAS_MAGICANEG)) {
 731                                         int idx;
 732
 733                                         /* We'll start from the
 734                                          * fastest speed, and work
 735                                          * our way down */
 736                                         idx = phy_find_valid(0,
 737                                                         phydev->supported);
 738
 739                                         phydev->speed = settings[idx].speed;
 740                                         phydev->duplex = settings[idx].duplex;
 741
 742                                         phydev->autoneg = AUTONEG_DISABLE;
 743                                         phydev->state = PHY_FORCING;
 744                                         phydev->link_timeout =
 745                                                 PHY_FORCE_TIMEOUT;
 746
 747                                         pr_info("Trying %d/%s\n",
 748                                                         phydev->speed,
 749                                                         DUPLEX_FULL ==
 750                                                         phydev->duplex ?
 751                                                         "FULL" : "HALF");
 752                                 }
 753
 754                                 needs_aneg = 1;
 755                         }
 756                         break;
 757                 case PHY_NOLINK:
 758                         err = phy_read_status(phydev);
 759
 760                         if (err)
 761                                 break;
 762
 763                         if (phydev->link) {
 764                                 phydev->state = PHY_RUNNING;
 765                                 netif_carrier_on(phydev->attached_dev);
 766                                 phydev->adjust_link(phydev->attached_dev);
 767                         }
 768                         break;
 769                 case PHY_FORCING:
 770                         err = phy_read_status(phydev);
 771
 772                         if (err)
 773                                 break;
 774
 775                         if (phydev->link) {
 776                                 phydev->state = PHY_RUNNING;
 777                                 netif_carrier_on(phydev->attached_dev);
 778                         } else {
 779                                 if (0 == phydev->link_timeout--) {
 780                                         phy_force_reduction(phydev);
 781                                         needs_aneg = 1;
 782                                 }
 783                         }
 784
 785                         phydev->adjust_link(phydev->attached_dev);
 786                         break;
 787                 case PHY_RUNNING:
 788                         /* Only register a CHANGE if we are
 789                          * polling */
 790                         if (PHY_POLL == phydev->irq)
 791                                 phydev->state = PHY_CHANGELINK;
 792                         break;
 793                 case PHY_CHANGELINK:
 794                         err = phy_read_status(phydev);
 795
 796                         if (err)
 797                                 break;
 798
 799                         if (phydev->link) {
 800                                 phydev->state = PHY_RUNNING;
 801                                 netif_carrier_on(phydev->attached_dev);
 802                         } else {
 803                                 phydev->state = PHY_NOLINK;
 804                                 netif_carrier_off(phydev->attached_dev);
 805                         }
 806
 807                         phydev->adjust_link(phydev->attached_dev);
 808
 809                         if (PHY_POLL != phydev->irq)
 810                                 err = phy_config_interrupt(phydev,
 811                                                 PHY_INTERRUPT_ENABLED);
 812                         break;
 813                 case PHY_HALTED:
 814                         if (phydev->link) {
 815                                 phydev->link = 0;
 816                                 netif_carrier_off(phydev->attached_dev);
 817                                 phydev->adjust_link(phydev->attached_dev);
 818                         }
 819                         break;
 820                 case PHY_RESUMING:
 821
 822                         err = phy_clear_interrupt(phydev);
 823
 824                         if (err)
 825                                 break;
 826
 827                         err = phy_config_interrupt(phydev,
 828                                         PHY_INTERRUPT_ENABLED);
 829
 830                         if (err)
 831                                 break;
 832
 833                         if (AUTONEG_ENABLE == phydev->autoneg) {
 834                                 err = phy_aneg_done(phydev);
 835                                 if (err < 0)
 836                                         break;
 837
 838                                 /* err > 0 if AN is done.
 839                                  * Otherwise, it's 0, and we're
 840                                  * still waiting for AN */
 841                                 if (err > 0) {
 842                                         phydev->state = PHY_RUNNING;
 843                                 } else {
 844                                         phydev->state = PHY_AN;
 845                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 846                                 }
 847                         } else
 848                                 phydev->state = PHY_RUNNING;
 849                         break;
 850         }
 851
 852         spin_unlock(&phydev->lock);
 853
 854         if (needs_aneg)
 855                 err = phy_start_aneg(phydev);
 856
 857         if (err < 0)
 858                 phy_error(phydev);
 859
 860         mod_timer(&phydev->phy_timer, jiffies + PHY_STATE_TIME * HZ);
 861 }
 862