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  * Copyright (c) 2006, 2007  Maciej W. Rozycki
  11  *
  12  * This program is free software; you can redistribute  it and/or modify it
  13  * under  the terms of  the GNU General  Public License as published by the
  14  * Free Software Foundation;  either version 2 of the  License, or (at your
  15  * option) any later version.
  16  *
  17  */
  18 #include <linux/kernel.h>
  19 #include <linux/string.h>
  20 #include <linux/errno.h>
  21 #include <linux/unistd.h>
  22 #include <linux/slab.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/init.h>
  25 #include <linux/delay.h>
  26 #include <linux/netdevice.h>
  27 #include <linux/etherdevice.h>
  28 #include <linux/skbuff.h>
  29 #include <linux/mm.h>
  30 #include <linux/module.h>
  31 #include <linux/mii.h>
  32 #include <linux/ethtool.h>
  33 #include <linux/phy.h>
  34 #include <linux/timer.h>
  35 #include <linux/workqueue.h>
  36
  37 #include <asm/atomic.h>
  38 #include <asm/io.h>
  39 #include <asm/irq.h>
  40 #include <asm/uaccess.h>
  41
  42 /**
  43  * phy_print_status - Convenience function to print out the current phy status
  44  * @phydev: the phy_device struct
  45  */
  46 void phy_print_status(struct phy_device *phydev)
  47 {
  48         pr_info("PHY: %s - Link is %s", dev_name(&phydev->dev),
  49                         phydev->link ? "Up" : "Down");
  50         if (phydev->link)
  51                 printk(" - %d/%s", phydev->speed,
  52                                 DUPLEX_FULL == phydev->duplex ?
  53                                 "Full" : "Half");
  54
  55         printk("\n");
  56 }
  57 EXPORT_SYMBOL(phy_print_status);
  58
  59
  60 /**
  61  * phy_clear_interrupt - Ack the phy device's interrupt
  62  * @phydev: the phy_device struct
  63  *
  64  * If the @phydev driver has an ack_interrupt function, call it to
  65  * ack and clear the phy device's interrupt.
  66  *
  67  * Returns 0 on success on < 0 on error.
  68  */
  69 int phy_clear_interrupt(struct phy_device *phydev)
  70 {
  71         int err = 0;
  72
  73         if (phydev->drv->ack_interrupt)
  74                 err = phydev->drv->ack_interrupt(phydev);
  75
  76         return err;
  77 }
  78
  79 /**
  80  * phy_config_interrupt - configure the PHY device for the requested interrupts
  81  * @phydev: the phy_device struct
  82  * @interrupts: interrupt flags to configure for this @phydev
  83  *
  84  * Returns 0 on success on < 0 on error.
  85  */
  86 int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
  87 {
  88         int err = 0;
  89
  90         phydev->interrupts = interrupts;
  91         if (phydev->drv->config_intr)
  92                 err = phydev->drv->config_intr(phydev);
  93
  94         return err;
  95 }
  96
  97
  98 /**
  99  * phy_aneg_done - return auto-negotiation status
 100  * @phydev: target phy_device struct
 101  *
 102  * Description: Reads the status register and returns 0 either if
 103  *   auto-negotiation is incomplete, or if there was an error.
 104  *   Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
 105  */
 106 static inline int phy_aneg_done(struct phy_device *phydev)
 107 {
 108         int retval;
 109
 110         retval = phy_read(phydev, MII_BMSR);
 111
 112         return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
 113 }
 114
 115 /* A structure for mapping a particular speed and duplex
 116  * combination to a particular SUPPORTED and ADVERTISED value */
 117 struct phy_setting {
 118         int speed;
 119         int duplex;
 120         u32 setting;
 121 };
 122
 123 /* A mapping of all SUPPORTED settings to speed/duplex */
 124 static const struct phy_setting settings[] = {
 125         {
 126                 .speed = 10000,
 127                 .duplex = DUPLEX_FULL,
 128                 .setting = SUPPORTED_10000baseT_Full,
 129         },
 130         {
 131                 .speed = SPEED_1000,
 132                 .duplex = DUPLEX_FULL,
 133                 .setting = SUPPORTED_1000baseT_Full,
 134         },
 135         {
 136                 .speed = SPEED_1000,
 137                 .duplex = DUPLEX_HALF,
 138                 .setting = SUPPORTED_1000baseT_Half,
 139         },
 140         {
 141                 .speed = SPEED_100,
 142                 .duplex = DUPLEX_FULL,
 143                 .setting = SUPPORTED_100baseT_Full,
 144         },
 145         {
 146                 .speed = SPEED_100,
 147                 .duplex = DUPLEX_HALF,
 148                 .setting = SUPPORTED_100baseT_Half,
 149         },
 150         {
 151                 .speed = SPEED_10,
 152                 .duplex = DUPLEX_FULL,
 153                 .setting = SUPPORTED_10baseT_Full,
 154         },
 155         {
 156                 .speed = SPEED_10,
 157                 .duplex = DUPLEX_HALF,
 158                 .setting = SUPPORTED_10baseT_Half,
 159         },
 160 };
 161
 162 #define MAX_NUM_SETTINGS ARRAY_SIZE(settings)
 163
 164 /**
 165  * phy_find_setting - find a PHY settings array entry that matches speed & duplex
 166  * @speed: speed to match
 167  * @duplex: duplex to match
 168  *
 169  * Description: Searches the settings array for the setting which
 170  *   matches the desired speed and duplex, and returns the index
 171  *   of that setting.  Returns the index of the last setting if
 172  *   none of the others match.
 173  */
 174 static inline int phy_find_setting(int speed, int duplex)
 175 {
 176         int idx = 0;
 177
 178         while (idx < ARRAY_SIZE(settings) &&
 179                         (settings[idx].speed != speed ||
 180                         settings[idx].duplex != duplex))
 181                 idx++;
 182
 183         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
 184 }
 185
 186 /**
 187  * phy_find_valid - find a PHY setting that matches the requested features mask
 188  * @idx: The first index in settings[] to search
 189  * @features: A mask of the valid settings
 190  *
 191  * Description: Returns the index of the first valid setting less
 192  *   than or equal to the one pointed to by idx, as determined by
 193  *   the mask in features.  Returns the index of the last setting
 194  *   if nothing else matches.
 195  */
 196 static inline int phy_find_valid(int idx, u32 features)
 197 {
 198         while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
 199                 idx++;
 200
 201         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
 202 }
 203
 204 /**
 205  * phy_sanitize_settings - make sure the PHY is set to supported speed and duplex
 206  * @phydev: the target phy_device struct
 207  *
 208  * Description: Make sure the PHY is set to supported speeds and
 209  *   duplexes.  Drop down by one in this order:  1000/FULL,
 210  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 211  */
 212 void phy_sanitize_settings(struct phy_device *phydev)
 213 {
 214         u32 features = phydev->supported;
 215         int idx;
 216
 217         /* Sanitize settings based on PHY capabilities */
 218         if ((features & SUPPORTED_Autoneg) == 0)
 219                 phydev->autoneg = AUTONEG_DISABLE;
 220
 221         idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
 222                         features);
 223
 224         phydev->speed = settings[idx].speed;
 225         phydev->duplex = settings[idx].duplex;
 226 }
 227 EXPORT_SYMBOL(phy_sanitize_settings);
 228
 229 /**
 230  * phy_ethtool_sset - generic ethtool sset function, handles all the details
 231  * @phydev: target phy_device struct
 232  * @cmd: ethtool_cmd
 233  *
 234  * A few notes about parameter checking:
 235  * - We don't set port or transceiver, so we don't care what they
 236  *   were set to.
 237  * - phy_start_aneg() will make sure forced settings are sane, and
 238  *   choose the next best ones from the ones selected, so we don't
 239  *   care if ethtool tries to give us bad values.
 240  */
 241 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 242 {
 243         if (cmd->phy_address != phydev->addr)
 244                 return -EINVAL;
 245
 246         /* We make sure that we don't pass unsupported
 247          * values in to the PHY */
 248         cmd->advertising &= phydev->supported;
 249
 250         /* Verify the settings we care about. */
 251         if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
 252                 return -EINVAL;
 253
 254         if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
 255                 return -EINVAL;
 256
 257         if (cmd->autoneg == AUTONEG_DISABLE &&
 258             ((cmd->speed != SPEED_1000 &&
 259               cmd->speed != SPEED_100 &&
 260               cmd->speed != SPEED_10) ||
 261              (cmd->duplex != DUPLEX_HALF &&
 262               cmd->duplex != DUPLEX_FULL)))
 263                 return -EINVAL;
 264
 265         phydev->autoneg = cmd->autoneg;
 266
 267         phydev->speed = cmd->speed;
 268
 269         phydev->advertising = cmd->advertising;
 270
 271         if (AUTONEG_ENABLE == cmd->autoneg)
 272                 phydev->advertising |= ADVERTISED_Autoneg;
 273         else
 274                 phydev->advertising &= ~ADVERTISED_Autoneg;
 275
 276         phydev->duplex = cmd->duplex;
 277
 278         /* Restart the PHY */
 279         phy_start_aneg(phydev);
 280
 281         return 0;
 282 }
 283 EXPORT_SYMBOL(phy_ethtool_sset);
 284
 285 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 286 {
 287         cmd->supported = phydev->supported;
 288
 289         cmd->advertising = phydev->advertising;
 290
 291         cmd->speed = phydev->speed;
 292         cmd->duplex = phydev->duplex;
 293         cmd->port = PORT_MII;
 294         cmd->phy_address = phydev->addr;
 295         cmd->transceiver = XCVR_EXTERNAL;
 296         cmd->autoneg = phydev->autoneg;
 297
 298         return 0;
 299 }
 300 EXPORT_SYMBOL(phy_ethtool_gset);
 301
 302 /**
 303  * phy_mii_ioctl - generic PHY MII ioctl interface
 304  * @phydev: the phy_device struct
 305  * @mii_data: MII ioctl data
 306  * @cmd: ioctl cmd to execute
 307  *
 308  * Note that this function is currently incompatible with the
 309  * PHYCONTROL layer.  It changes registers without regard to
 310  * current state.  Use at own risk.
 311  */
 312 int phy_mii_ioctl(struct phy_device *phydev,
 313                 struct mii_ioctl_data *mii_data, int cmd)
 314 {
 315         u16 val = mii_data->val_in;
 316
 317         switch (cmd) {
 318         case SIOCGMIIPHY:
 319                 mii_data->phy_id = phydev->addr;
 320                 /* fall through */
 321
 322         case SIOCGMIIREG:
 323                 mii_data->val_out = phy_read(phydev, mii_data->reg_num);
 324                 break;
 325
 326         case SIOCSMIIREG:
 327                 if (mii_data->phy_id == phydev->addr) {
 328                         switch(mii_data->reg_num) {
 329                         case MII_BMCR:
 330                                 if ((val & (BMCR_RESET|BMCR_ANENABLE)) == 0)
 331                                         phydev->autoneg = AUTONEG_DISABLE;
 332                                 else
 333                                         phydev->autoneg = AUTONEG_ENABLE;
 334                                 if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
 335                                         phydev->duplex = DUPLEX_FULL;
 336                                 else
 337                                         phydev->duplex = DUPLEX_HALF;
 338                                 if ((!phydev->autoneg) &&
 339                                                 (val & BMCR_SPEED1000))
 340                                         phydev->speed = SPEED_1000;
 341                                 else if ((!phydev->autoneg) &&
 342                                                 (val & BMCR_SPEED100))
 343                                         phydev->speed = SPEED_100;
 344                                 break;
 345                         case MII_ADVERTISE:
 346                                 phydev->advertising = val;
 347                                 break;
 348                         default:
 349                                 /* do nothing */
 350                                 break;
 351                         }
 352                 }
 353
 354                 phy_write(phydev, mii_data->reg_num, val);
 355
 356                 if (mii_data->reg_num == MII_BMCR &&
 357                     val & BMCR_RESET &&
 358                     phydev->drv->config_init) {
 359                         phy_scan_fixups(phydev);
 360                         phydev->drv->config_init(phydev);
 361                 }
 362                 break;
 363
 364         default:
 365                 return -EOPNOTSUPP;
 366         }
 367
 368         return 0;
 369 }
 370 EXPORT_SYMBOL(phy_mii_ioctl);
 371
 372 /**
 373  * phy_start_aneg - start auto-negotiation for this PHY device
 374  * @phydev: the phy_device struct
 375  *
 376  * Description: Sanitizes the settings (if we're not autonegotiating
 377  *   them), and then calls the driver's config_aneg function.
 378  *   If the PHYCONTROL Layer is operating, we change the state to
 379  *   reflect the beginning of Auto-negotiation or forcing.
 380  */
 381 int phy_start_aneg(struct phy_device *phydev)
 382 {
 383         int err;
 384
 385         mutex_lock(&phydev->lock);
 386
 387         if (AUTONEG_DISABLE == phydev->autoneg)
 388                 phy_sanitize_settings(phydev);
 389
 390         err = phydev->drv->config_aneg(phydev);
 391
 392         if (err < 0)
 393                 goto out_unlock;
 394
 395         if (phydev->state != PHY_HALTED) {
 396                 if (AUTONEG_ENABLE == phydev->autoneg) {
 397                         phydev->state = PHY_AN;
 398                         phydev->link_timeout = PHY_AN_TIMEOUT;
 399                 } else {
 400                         phydev->state = PHY_FORCING;
 401                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
 402                 }
 403         }
 404
 405 out_unlock:
 406         mutex_unlock(&phydev->lock);
 407         return err;
 408 }
 409 EXPORT_SYMBOL(phy_start_aneg);
 410
 411
 412 static void phy_change(struct work_struct *work);
 413
 414 /**
 415  * phy_start_machine - start PHY state machine tracking
 416  * @phydev: the phy_device struct
 417  * @handler: callback function for state change notifications
 418  *
 419  * Description: The PHY infrastructure can run a state machine
 420  *   which tracks whether the PHY is starting up, negotiating,
 421  *   etc.  This function starts the timer which tracks the state
 422  *   of the PHY.  If you want to be notified when the state changes,
 423  *   pass in the callback @handler, otherwise, pass NULL.  If you
 424  *   want to maintain your own state machine, do not call this
 425  *   function.
 426  */
 427 void phy_start_machine(struct phy_device *phydev,
 428                 void (*handler)(struct net_device *))
 429 {
 430         phydev->adjust_state = handler;
 431
 432         schedule_delayed_work(&phydev->state_queue, HZ);
 433 }
 434
 435 /**
 436  * phy_stop_machine - stop the PHY state machine tracking
 437  * @phydev: target phy_device struct
 438  *
 439  * Description: Stops the state machine timer, sets the state to UP
 440  *   (unless it wasn't up yet). This function must be called BEFORE
 441  *   phy_detach.
 442  */
 443 void phy_stop_machine(struct phy_device *phydev)
 444 {
 445         cancel_delayed_work_sync(&phydev->state_queue);
 446
 447         mutex_lock(&phydev->lock);
 448         if (phydev->state > PHY_UP)
 449                 phydev->state = PHY_UP;
 450         mutex_unlock(&phydev->lock);
 451
 452         phydev->adjust_state = NULL;
 453 }
 454
 455 /**
 456  * phy_force_reduction - reduce PHY speed/duplex settings by one step
 457  * @phydev: target phy_device struct
 458  *
 459  * Description: Reduces the speed/duplex settings by one notch,
 460  *   in this order--
 461  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 462  *   The function bottoms out at 10/HALF.
 463  */
 464 static void phy_force_reduction(struct phy_device *phydev)
 465 {
 466         int idx;
 467
 468         idx = phy_find_setting(phydev->speed, phydev->duplex);
 469
 470         idx++;
 471
 472         idx = phy_find_valid(idx, phydev->supported);
 473
 474         phydev->speed = settings[idx].speed;
 475         phydev->duplex = settings[idx].duplex;
 476
 477         pr_info("Trying %d/%s\n", phydev->speed,
 478                         DUPLEX_FULL == phydev->duplex ?
 479                         "FULL" : "HALF");
 480 }
 481
 482
 483 /**
 484  * phy_error - enter HALTED state for this PHY device
 485  * @phydev: target phy_device struct
 486  *
 487  * Moves the PHY to the HALTED state in response to a read
 488  * or write error, and tells the controller the link is down.
 489  * Must not be called from interrupt context, or while the
 490  * phydev->lock is held.
 491  */
 492 static void phy_error(struct phy_device *phydev)
 493 {
 494         mutex_lock(&phydev->lock);
 495         phydev->state = PHY_HALTED;
 496         mutex_unlock(&phydev->lock);
 497 }
 498
 499 /**
 500  * phy_interrupt - PHY interrupt handler
 501  * @irq: interrupt line
 502  * @phy_dat: phy_device pointer
 503  *
 504  * Description: When a PHY interrupt occurs, the handler disables
 505  * interrupts, and schedules a work task to clear the interrupt.
 506  */
 507 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 508 {
 509         struct phy_device *phydev = phy_dat;
 510
 511         if (PHY_HALTED == phydev->state)
 512                 return IRQ_NONE;                /* It can't be ours.  */
 513
 514         /* The MDIO bus is not allowed to be written in interrupt
 515          * context, so we need to disable the irq here.  A work
 516          * queue will write the PHY to disable and clear the
 517          * interrupt, and then reenable the irq line. */
 518         disable_irq_nosync(irq);
 519         atomic_inc(&phydev->irq_disable);
 520
 521         schedule_work(&phydev->phy_queue);
 522
 523         return IRQ_HANDLED;
 524 }
 525
 526 /**
 527  * phy_enable_interrupts - Enable the interrupts from the PHY side
 528  * @phydev: target phy_device struct
 529  */
 530 int phy_enable_interrupts(struct phy_device *phydev)
 531 {
 532         int err;
 533
 534         err = phy_clear_interrupt(phydev);
 535
 536         if (err < 0)
 537                 return err;
 538
 539         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 540
 541         return err;
 542 }
 543 EXPORT_SYMBOL(phy_enable_interrupts);
 544
 545 /**
 546  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
 547  * @phydev: target phy_device struct
 548  */
 549 int phy_disable_interrupts(struct phy_device *phydev)
 550 {
 551         int err;
 552
 553         /* Disable PHY interrupts */
 554         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 555
 556         if (err)
 557                 goto phy_err;
 558
 559         /* Clear the interrupt */
 560         err = phy_clear_interrupt(phydev);
 561
 562         if (err)
 563                 goto phy_err;
 564
 565         return 0;
 566
 567 phy_err:
 568         phy_error(phydev);
 569
 570         return err;
 571 }
 572 EXPORT_SYMBOL(phy_disable_interrupts);
 573
 574 /**
 575  * phy_start_interrupts - request and enable interrupts for a PHY device
 576  * @phydev: target phy_device struct
 577  *
 578  * Description: Request the interrupt for the given PHY.
 579  *   If this fails, then we set irq to PHY_POLL.
 580  *   Otherwise, we enable the interrupts in the PHY.
 581  *   This should only be called with a valid IRQ number.
 582  *   Returns 0 on success or < 0 on error.
 583  */
 584 int phy_start_interrupts(struct phy_device *phydev)
 585 {
 586         int err = 0;
 587
 588         INIT_WORK(&phydev->phy_queue, phy_change);
 589
 590         atomic_set(&phydev->irq_disable, 0);
 591         if (request_irq(phydev->irq, phy_interrupt,
 592                                 IRQF_SHARED,
 593                                 "phy_interrupt",
 594                                 phydev) < 0) {
 595                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 596                                 phydev->bus->name,
 597                                 phydev->irq);
 598                 phydev->irq = PHY_POLL;
 599                 return 0;
 600         }
 601
 602         err = phy_enable_interrupts(phydev);
 603
 604         return err;
 605 }
 606 EXPORT_SYMBOL(phy_start_interrupts);
 607
 608 /**
 609  * phy_stop_interrupts - disable interrupts from a PHY device
 610  * @phydev: target phy_device struct
 611  */
 612 int phy_stop_interrupts(struct phy_device *phydev)
 613 {
 614         int err;
 615
 616         err = phy_disable_interrupts(phydev);
 617
 618         if (err)
 619                 phy_error(phydev);
 620
 621         free_irq(phydev->irq, phydev);
 622
 623         /*
 624          * Cannot call flush_scheduled_work() here as desired because
 625          * of rtnl_lock(), but we do not really care about what would
 626          * be done, except from enable_irq(), so cancel any work
 627          * possibly pending and take care of the matter below.
 628          */
 629         cancel_work_sync(&phydev->phy_queue);
 630         /*
 631          * If work indeed has been cancelled, disable_irq() will have
 632          * been left unbalanced from phy_interrupt() and enable_irq()
 633          * has to be called so that other devices on the line work.
 634          */
 635         while (atomic_dec_return(&phydev->irq_disable) >= 0)
 636                 enable_irq(phydev->irq);
 637
 638         return err;
 639 }
 640 EXPORT_SYMBOL(phy_stop_interrupts);
 641
 642
 643 /**
 644  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
 645  * @work: work_struct that describes the work to be done
 646  */
 647 static void phy_change(struct work_struct *work)
 648 {
 649         int err;
 650         struct phy_device *phydev =
 651                 container_of(work, struct phy_device, phy_queue);
 652
 653         if (phydev->drv->did_interrupt &&
 654             !phydev->drv->did_interrupt(phydev))
 655                 goto ignore;
 656
 657         err = phy_disable_interrupts(phydev);
 658
 659         if (err)
 660                 goto phy_err;
 661
 662         mutex_lock(&phydev->lock);
 663         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 664                 phydev->state = PHY_CHANGELINK;
 665         mutex_unlock(&phydev->lock);
 666
 667         atomic_dec(&phydev->irq_disable);
 668         enable_irq(phydev->irq);
 669
 670         /* Reenable interrupts */
 671         if (PHY_HALTED != phydev->state)
 672                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 673
 674         if (err)
 675                 goto irq_enable_err;
 676
 677         /* reschedule state queue work to run as soon as possible */
 678         cancel_delayed_work_sync(&phydev->state_queue);
 679         schedule_delayed_work(&phydev->state_queue, 0);
 680
 681         return;
 682
 683 ignore:
 684         atomic_dec(&phydev->irq_disable);
 685         enable_irq(phydev->irq);
 686         return;
 687
 688 irq_enable_err:
 689         disable_irq(phydev->irq);
 690         atomic_inc(&phydev->irq_disable);
 691 phy_err:
 692         phy_error(phydev);
 693 }
 694
 695 /**
 696  * phy_stop - Bring down the PHY link, and stop checking the status
 697  * @phydev: target phy_device struct
 698  */
 699 void phy_stop(struct phy_device *phydev)
 700 {
 701         mutex_lock(&phydev->lock);
 702
 703         if (PHY_HALTED == phydev->state)
 704                 goto out_unlock;
 705
 706         if (phydev->irq != PHY_POLL) {
 707                 /* Disable PHY Interrupts */
 708                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 709
 710                 /* Clear any pending interrupts */
 711                 phy_clear_interrupt(phydev);
 712         }
 713
 714         phydev->state = PHY_HALTED;
 715
 716 out_unlock:
 717         mutex_unlock(&phydev->lock);
 718
 719         /*
 720          * Cannot call flush_scheduled_work() here as desired because
 721          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
 722          * will not reenable interrupts.
 723          */
 724 }
 725
 726
 727 /**
 728  * phy_start - start or restart a PHY device
 729  * @phydev: target phy_device struct
 730  *
 731  * Description: Indicates the attached device's readiness to
 732  *   handle PHY-related work.  Used during startup to start the
 733  *   PHY, and after a call to phy_stop() to resume operation.
 734  *   Also used to indicate the MDIO bus has cleared an error
 735  *   condition.
 736  */
 737 void phy_start(struct phy_device *phydev)
 738 {
 739         mutex_lock(&phydev->lock);
 740
 741         switch (phydev->state) {
 742                 case PHY_STARTING:
 743                         phydev->state = PHY_PENDING;
 744                         break;
 745                 case PHY_READY:
 746                         phydev->state = PHY_UP;
 747                         break;
 748                 case PHY_HALTED:
 749                         phydev->state = PHY_RESUMING;
 750                 default:
 751                         break;
 752         }
 753         mutex_unlock(&phydev->lock);
 754 }
 755 EXPORT_SYMBOL(phy_stop);
 756 EXPORT_SYMBOL(phy_start);
 757
 758 /**
 759  * phy_state_machine - Handle the state machine
 760  * @work: work_struct that describes the work to be done
 761  */
 762 void phy_state_machine(struct work_struct *work)
 763 {
 764         struct delayed_work *dwork = to_delayed_work(work);
 765         struct phy_device *phydev =
 766                         container_of(dwork, struct phy_device, state_queue);
 767         int needs_aneg = 0;
 768         int err = 0;
 769
 770         mutex_lock(&phydev->lock);
 771
 772         if (phydev->adjust_state)
 773                 phydev->adjust_state(phydev->attached_dev);
 774
 775         switch(phydev->state) {
 776                 case PHY_DOWN:
 777                 case PHY_STARTING:
 778                 case PHY_READY:
 779                 case PHY_PENDING:
 780                         break;
 781                 case PHY_UP:
 782                         needs_aneg = 1;
 783
 784                         phydev->link_timeout = PHY_AN_TIMEOUT;
 785
 786                         break;
 787                 case PHY_AN:
 788                         err = phy_read_status(phydev);
 789
 790                         if (err < 0)
 791                                 break;
 792
 793                         /* If the link is down, give up on
 794                          * negotiation for now */
 795                         if (!phydev->link) {
 796                                 phydev->state = PHY_NOLINK;
 797                                 netif_carrier_off(phydev->attached_dev);
 798                                 phydev->adjust_link(phydev->attached_dev);
 799                                 break;
 800                         }
 801
 802                         /* Check if negotiation is done.  Break
 803                          * if there's an error */
 804                         err = phy_aneg_done(phydev);
 805                         if (err < 0)
 806                                 break;
 807
 808                         /* If AN is done, we're running */
 809                         if (err > 0) {
 810                                 phydev->state = PHY_RUNNING;
 811                                 netif_carrier_on(phydev->attached_dev);
 812                                 phydev->adjust_link(phydev->attached_dev);
 813
 814                         } else if (0 == phydev->link_timeout--) {
 815                                 int idx;
 816
 817                                 needs_aneg = 1;
 818                                 /* If we have the magic_aneg bit,
 819                                  * we try again */
 820                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
 821                                         break;
 822
 823                                 /* The timer expired, and we still
 824                                  * don't have a setting, so we try
 825                                  * forcing it until we find one that
 826                                  * works, starting from the fastest speed,
 827                                  * and working our way down */
 828                                 idx = phy_find_valid(0, phydev->supported);
 829
 830                                 phydev->speed = settings[idx].speed;
 831                                 phydev->duplex = settings[idx].duplex;
 832
 833                                 phydev->autoneg = AUTONEG_DISABLE;
 834
 835                                 pr_info("Trying %d/%s\n", phydev->speed,
 836                                                 DUPLEX_FULL ==
 837                                                 phydev->duplex ?
 838                                                 "FULL" : "HALF");
 839                         }
 840                         break;
 841                 case PHY_NOLINK:
 842                         err = phy_read_status(phydev);
 843
 844                         if (err)
 845                                 break;
 846
 847                         if (phydev->link) {
 848                                 phydev->state = PHY_RUNNING;
 849                                 netif_carrier_on(phydev->attached_dev);
 850                                 phydev->adjust_link(phydev->attached_dev);
 851                         }
 852                         break;
 853                 case PHY_FORCING:
 854                         err = genphy_update_link(phydev);
 855
 856                         if (err)
 857                                 break;
 858
 859                         if (phydev->link) {
 860                                 phydev->state = PHY_RUNNING;
 861                                 netif_carrier_on(phydev->attached_dev);
 862                         } else {
 863                                 if (0 == phydev->link_timeout--) {
 864                                         phy_force_reduction(phydev);
 865                                         needs_aneg = 1;
 866                                 }
 867                         }
 868
 869                         phydev->adjust_link(phydev->attached_dev);
 870                         break;
 871                 case PHY_RUNNING:
 872                         /* Only register a CHANGE if we are
 873                          * polling */
 874                         if (PHY_POLL == phydev->irq)
 875                                 phydev->state = PHY_CHANGELINK;
 876                         break;
 877                 case PHY_CHANGELINK:
 878                         err = phy_read_status(phydev);
 879
 880                         if (err)
 881                                 break;
 882
 883                         if (phydev->link) {
 884                                 phydev->state = PHY_RUNNING;
 885                                 netif_carrier_on(phydev->attached_dev);
 886                         } else {
 887                                 phydev->state = PHY_NOLINK;
 888                                 netif_carrier_off(phydev->attached_dev);
 889                         }
 890
 891                         phydev->adjust_link(phydev->attached_dev);
 892
 893                         if (PHY_POLL != phydev->irq)
 894                                 err = phy_config_interrupt(phydev,
 895                                                 PHY_INTERRUPT_ENABLED);
 896                         break;
 897                 case PHY_HALTED:
 898                         if (phydev->link) {
 899                                 phydev->link = 0;
 900                                 netif_carrier_off(phydev->attached_dev);
 901                                 phydev->adjust_link(phydev->attached_dev);
 902                         }
 903                         break;
 904                 case PHY_RESUMING:
 905
 906                         err = phy_clear_interrupt(phydev);
 907
 908                         if (err)
 909                                 break;
 910
 911                         err = phy_config_interrupt(phydev,
 912                                         PHY_INTERRUPT_ENABLED);
 913
 914                         if (err)
 915                                 break;
 916
 917                         if (AUTONEG_ENABLE == phydev->autoneg) {
 918                                 err = phy_aneg_done(phydev);
 919                                 if (err < 0)
 920                                         break;
 921
 922                                 /* err > 0 if AN is done.
 923                                  * Otherwise, it's 0, and we're
 924                                  * still waiting for AN */
 925                                 if (err > 0) {
 926                                         err = phy_read_status(phydev);
 927                                         if (err)
 928                                                 break;
 929
 930                                         if (phydev->link) {
 931                                                 phydev->state = PHY_RUNNING;
 932                                                 netif_carrier_on(phydev->attached_dev);
 933                                         } else
 934                                                 phydev->state = PHY_NOLINK;
 935                                         phydev->adjust_link(phydev->attached_dev);
 936                                 } else {
 937                                         phydev->state = PHY_AN;
 938                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 939                                 }
 940                         } else {
 941                                 err = phy_read_status(phydev);
 942                                 if (err)
 943                                         break;
 944
 945                                 if (phydev->link) {
 946                                         phydev->state = PHY_RUNNING;
 947                                         netif_carrier_on(phydev->attached_dev);
 948                                 } else
 949                                         phydev->state = PHY_NOLINK;
 950                                 phydev->adjust_link(phydev->attached_dev);
 951                         }
 952                         break;
 953         }
 954
 955         mutex_unlock(&phydev->lock);
 956
 957         if (needs_aneg)
 958                 err = phy_start_aneg(phydev);
 959
 960         if (err < 0)
 961                 phy_error(phydev);
 962
 963         schedule_delayed_work(&phydev->state_queue, PHY_STATE_TIME * HZ);
 964 }