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/interrupt.h>
  23 #include <linux/init.h>
  24 #include <linux/delay.h>
  25 #include <linux/netdevice.h>
  26 #include <linux/etherdevice.h>
  27 #include <linux/skbuff.h>
  28 #include <linux/mm.h>
  29 #include <linux/module.h>
  30 #include <linux/mii.h>
  31 #include <linux/ethtool.h>
  32 #include <linux/phy.h>
  33 #include <linux/timer.h>
  34 #include <linux/workqueue.h>
  35
  36 #include <linux/atomic.h>
  37 #include <asm/io.h>
  38 #include <asm/irq.h>
  39 #include <asm/uaccess.h>
  40
  41 /**
  42  * phy_print_status - Convenience function to print out the current phy status
  43  * @phydev: the phy_device struct
  44  */
  45 void phy_print_status(struct phy_device *phydev)
  46 {
  47         pr_info("PHY: %s - Link is %s", dev_name(&phydev->dev),
  48                         phydev->link ? "Up" : "Down");
  49         if (phydev->link)
  50                 printk(KERN_CONT " - %d/%s", phydev->speed,
  51                                 DUPLEX_FULL == phydev->duplex ?
  52                                 "Full" : "Half");
  53
  54         printk(KERN_CONT "\n");
  55 }
  56 EXPORT_SYMBOL(phy_print_status);
  57
  58
  59 /**
  60  * phy_clear_interrupt - Ack the phy device's interrupt
  61  * @phydev: the phy_device struct
  62  *
  63  * If the @phydev driver has an ack_interrupt function, call it to
  64  * ack and clear the phy device's interrupt.
  65  *
  66  * Returns 0 on success on < 0 on error.
  67  */
  68 static int phy_clear_interrupt(struct phy_device *phydev)
  69 {
  70         int err = 0;
  71
  72         if (phydev->drv->ack_interrupt)
  73                 err = phydev->drv->ack_interrupt(phydev);
  74
  75         return err;
  76 }
  77
  78 /**
  79  * phy_config_interrupt - configure the PHY device for the requested interrupts
  80  * @phydev: the phy_device struct
  81  * @interrupts: interrupt flags to configure for this @phydev
  82  *
  83  * Returns 0 on success on < 0 on error.
  84  */
  85 static int phy_config_interrupt(struct phy_device *phydev, u32 interrupts)
  86 {
  87         int err = 0;
  88
  89         phydev->interrupts = interrupts;
  90         if (phydev->drv->config_intr)
  91                 err = phydev->drv->config_intr(phydev);
  92
  93         return err;
  94 }
  95
  96
  97 /**
  98  * phy_aneg_done - return auto-negotiation status
  99  * @phydev: target phy_device struct
 100  *
 101  * Description: Reads the status register and returns 0 either if
 102  *   auto-negotiation is incomplete, or if there was an error.
 103  *   Returns BMSR_ANEGCOMPLETE if auto-negotiation is done.
 104  */
 105 static inline int phy_aneg_done(struct phy_device *phydev)
 106 {
 107         int retval;
 108
 109         retval = phy_read(phydev, MII_BMSR);
 110
 111         return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
 112 }
 113
 114 /* A structure for mapping a particular speed and duplex
 115  * combination to a particular SUPPORTED and ADVERTISED value */
 116 struct phy_setting {
 117         int speed;
 118         int duplex;
 119         u32 setting;
 120 };
 121
 122 /* A mapping of all SUPPORTED settings to speed/duplex */
 123 static const struct phy_setting settings[] = {
 124         {
 125                 .speed = 10000,
 126                 .duplex = DUPLEX_FULL,
 127                 .setting = SUPPORTED_10000baseT_Full,
 128         },
 129         {
 130                 .speed = SPEED_1000,
 131                 .duplex = DUPLEX_FULL,
 132                 .setting = SUPPORTED_1000baseT_Full,
 133         },
 134         {
 135                 .speed = SPEED_1000,
 136                 .duplex = DUPLEX_HALF,
 137                 .setting = SUPPORTED_1000baseT_Half,
 138         },
 139         {
 140                 .speed = SPEED_100,
 141                 .duplex = DUPLEX_FULL,
 142                 .setting = SUPPORTED_100baseT_Full,
 143         },
 144         {
 145                 .speed = SPEED_100,
 146                 .duplex = DUPLEX_HALF,
 147                 .setting = SUPPORTED_100baseT_Half,
 148         },
 149         {
 150                 .speed = SPEED_10,
 151                 .duplex = DUPLEX_FULL,
 152                 .setting = SUPPORTED_10baseT_Full,
 153         },
 154         {
 155                 .speed = SPEED_10,
 156                 .duplex = DUPLEX_HALF,
 157                 .setting = SUPPORTED_10baseT_Half,
 158         },
 159 };
 160
 161 #define MAX_NUM_SETTINGS ARRAY_SIZE(settings)
 162
 163 /**
 164  * phy_find_setting - find a PHY settings array entry that matches speed & duplex
 165  * @speed: speed to match
 166  * @duplex: duplex to match
 167  *
 168  * Description: Searches the settings array for the setting which
 169  *   matches the desired speed and duplex, and returns the index
 170  *   of that setting.  Returns the index of the last setting if
 171  *   none of the others match.
 172  */
 173 static inline int phy_find_setting(int speed, int duplex)
 174 {
 175         int idx = 0;
 176
 177         while (idx < ARRAY_SIZE(settings) &&
 178                         (settings[idx].speed != speed ||
 179                         settings[idx].duplex != duplex))
 180                 idx++;
 181
 182         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
 183 }
 184
 185 /**
 186  * phy_find_valid - find a PHY setting that matches the requested features mask
 187  * @idx: The first index in settings[] to search
 188  * @features: A mask of the valid settings
 189  *
 190  * Description: Returns the index of the first valid setting less
 191  *   than or equal to the one pointed to by idx, as determined by
 192  *   the mask in features.  Returns the index of the last setting
 193  *   if nothing else matches.
 194  */
 195 static inline int phy_find_valid(int idx, u32 features)
 196 {
 197         while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features))
 198                 idx++;
 199
 200         return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1;
 201 }
 202
 203 /**
 204  * phy_sanitize_settings - make sure the PHY is set to supported speed and duplex
 205  * @phydev: the target phy_device struct
 206  *
 207  * Description: Make sure the PHY is set to supported speeds and
 208  *   duplexes.  Drop down by one in this order:  1000/FULL,
 209  *   1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 210  */
 211 static void phy_sanitize_settings(struct phy_device *phydev)
 212 {
 213         u32 features = phydev->supported;
 214         int idx;
 215
 216         /* Sanitize settings based on PHY capabilities */
 217         if ((features & SUPPORTED_Autoneg) == 0)
 218                 phydev->autoneg = AUTONEG_DISABLE;
 219
 220         idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex),
 221                         features);
 222
 223         phydev->speed = settings[idx].speed;
 224         phydev->duplex = settings[idx].duplex;
 225 }
 226
 227 /**
 228  * phy_ethtool_sset - generic ethtool sset function, handles all the details
 229  * @phydev: target phy_device struct
 230  * @cmd: ethtool_cmd
 231  *
 232  * A few notes about parameter checking:
 233  * - We don't set port or transceiver, so we don't care what they
 234  *   were set to.
 235  * - phy_start_aneg() will make sure forced settings are sane, and
 236  *   choose the next best ones from the ones selected, so we don't
 237  *   care if ethtool tries to give us bad values.
 238  */
 239 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 240 {
 241         u32 speed = ethtool_cmd_speed(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             ((speed != SPEED_1000 &&
 259               speed != SPEED_100 &&
 260               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 = 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         ethtool_cmd_speed_set(cmd, 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  * @ifr: &struct ifreq for socket ioctl's
 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 ifreq *ifr, int cmd)
 314 {
 315         struct mii_ioctl_data *mii_data = if_mii(ifr);
 316         u16 val = mii_data->val_in;
 317
 318         switch (cmd) {
 319         case SIOCGMIIPHY:
 320                 mii_data->phy_id = phydev->addr;
 321                 /* fall through */
 322
 323         case SIOCGMIIREG:
 324                 mii_data->val_out = mdiobus_read(phydev->bus, mii_data->phy_id,
 325                                                  mii_data->reg_num);
 326                 break;
 327
 328         case SIOCSMIIREG:
 329                 if (mii_data->phy_id == phydev->addr) {
 330                         switch(mii_data->reg_num) {
 331                         case MII_BMCR:
 332                                 if ((val & (BMCR_RESET|BMCR_ANENABLE)) == 0)
 333                                         phydev->autoneg = AUTONEG_DISABLE;
 334                                 else
 335                                         phydev->autoneg = AUTONEG_ENABLE;
 336                                 if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
 337                                         phydev->duplex = DUPLEX_FULL;
 338                                 else
 339                                         phydev->duplex = DUPLEX_HALF;
 340                                 if ((!phydev->autoneg) &&
 341                                                 (val & BMCR_SPEED1000))
 342                                         phydev->speed = SPEED_1000;
 343                                 else if ((!phydev->autoneg) &&
 344                                                 (val & BMCR_SPEED100))
 345                                         phydev->speed = SPEED_100;
 346                                 break;
 347                         case MII_ADVERTISE:
 348                                 phydev->advertising = val;
 349                                 break;
 350                         default:
 351                                 /* do nothing */
 352                                 break;
 353                         }
 354                 }
 355
 356                 mdiobus_write(phydev->bus, mii_data->phy_id,
 357                               mii_data->reg_num, val);
 358
 359                 if (mii_data->reg_num == MII_BMCR &&
 360                     val & BMCR_RESET &&
 361                     phydev->drv->config_init) {
 362                         phy_scan_fixups(phydev);
 363                         phydev->drv->config_init(phydev);
 364                 }
 365                 break;
 366
 367         case SIOCSHWTSTAMP:
 368                 if (phydev->drv->hwtstamp)
 369                         return phydev->drv->hwtstamp(phydev, ifr);
 370                 /* fall through */
 371
 372         default:
 373                 return -EOPNOTSUPP;
 374         }
 375
 376         return 0;
 377 }
 378 EXPORT_SYMBOL(phy_mii_ioctl);
 379
 380 /**
 381  * phy_start_aneg - start auto-negotiation for this PHY device
 382  * @phydev: the phy_device struct
 383  *
 384  * Description: Sanitizes the settings (if we're not autonegotiating
 385  *   them), and then calls the driver's config_aneg function.
 386  *   If the PHYCONTROL Layer is operating, we change the state to
 387  *   reflect the beginning of Auto-negotiation or forcing.
 388  */
 389 int phy_start_aneg(struct phy_device *phydev)
 390 {
 391         int err;
 392
 393         mutex_lock(&phydev->lock);
 394
 395         if (AUTONEG_DISABLE == phydev->autoneg)
 396                 phy_sanitize_settings(phydev);
 397
 398         err = phydev->drv->config_aneg(phydev);
 399
 400         if (err < 0)
 401                 goto out_unlock;
 402
 403         if (phydev->state != PHY_HALTED) {
 404                 if (AUTONEG_ENABLE == phydev->autoneg) {
 405                         phydev->state = PHY_AN;
 406                         phydev->link_timeout = PHY_AN_TIMEOUT;
 407                 } else {
 408                         phydev->state = PHY_FORCING;
 409                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
 410                 }
 411         }
 412
 413 out_unlock:
 414         mutex_unlock(&phydev->lock);
 415         return err;
 416 }
 417 EXPORT_SYMBOL(phy_start_aneg);
 418
 419
 420 static void phy_change(struct work_struct *work);
 421
 422 /**
 423  * phy_start_machine - start PHY state machine tracking
 424  * @phydev: the phy_device struct
 425  * @handler: callback function for state change notifications
 426  *
 427  * Description: The PHY infrastructure can run a state machine
 428  *   which tracks whether the PHY is starting up, negotiating,
 429  *   etc.  This function starts the timer which tracks the state
 430  *   of the PHY.  If you want to be notified when the state changes,
 431  *   pass in the callback @handler, otherwise, pass NULL.  If you
 432  *   want to maintain your own state machine, do not call this
 433  *   function.
 434  */
 435 void phy_start_machine(struct phy_device *phydev,
 436                 void (*handler)(struct net_device *))
 437 {
 438         phydev->adjust_state = handler;
 439
 440         schedule_delayed_work(&phydev->state_queue, HZ);
 441 }
 442
 443 /**
 444  * phy_stop_machine - stop the PHY state machine tracking
 445  * @phydev: target phy_device struct
 446  *
 447  * Description: Stops the state machine timer, sets the state to UP
 448  *   (unless it wasn't up yet). This function must be called BEFORE
 449  *   phy_detach.
 450  */
 451 void phy_stop_machine(struct phy_device *phydev)
 452 {
 453         cancel_delayed_work_sync(&phydev->state_queue);
 454
 455         mutex_lock(&phydev->lock);
 456         if (phydev->state > PHY_UP)
 457                 phydev->state = PHY_UP;
 458         mutex_unlock(&phydev->lock);
 459
 460         phydev->adjust_state = NULL;
 461 }
 462
 463 /**
 464  * phy_force_reduction - reduce PHY speed/duplex settings by one step
 465  * @phydev: target phy_device struct
 466  *
 467  * Description: Reduces the speed/duplex settings by one notch,
 468  *   in this order--
 469  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 470  *   The function bottoms out at 10/HALF.
 471  */
 472 static void phy_force_reduction(struct phy_device *phydev)
 473 {
 474         int idx;
 475
 476         idx = phy_find_setting(phydev->speed, phydev->duplex);
 477
 478         idx++;
 479
 480         idx = phy_find_valid(idx, phydev->supported);
 481
 482         phydev->speed = settings[idx].speed;
 483         phydev->duplex = settings[idx].duplex;
 484
 485         pr_info("Trying %d/%s\n", phydev->speed,
 486                         DUPLEX_FULL == phydev->duplex ?
 487                         "FULL" : "HALF");
 488 }
 489
 490
 491 /**
 492  * phy_error - enter HALTED state for this PHY device
 493  * @phydev: target phy_device struct
 494  *
 495  * Moves the PHY to the HALTED state in response to a read
 496  * or write error, and tells the controller the link is down.
 497  * Must not be called from interrupt context, or while the
 498  * phydev->lock is held.
 499  */
 500 static void phy_error(struct phy_device *phydev)
 501 {
 502         mutex_lock(&phydev->lock);
 503         phydev->state = PHY_HALTED;
 504         mutex_unlock(&phydev->lock);
 505 }
 506
 507 /**
 508  * phy_interrupt - PHY interrupt handler
 509  * @irq: interrupt line
 510  * @phy_dat: phy_device pointer
 511  *
 512  * Description: When a PHY interrupt occurs, the handler disables
 513  * interrupts, and schedules a work task to clear the interrupt.
 514  */
 515 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 516 {
 517         struct phy_device *phydev = phy_dat;
 518
 519         if (PHY_HALTED == phydev->state)
 520                 return IRQ_NONE;                /* It can't be ours.  */
 521
 522         /* The MDIO bus is not allowed to be written in interrupt
 523          * context, so we need to disable the irq here.  A work
 524          * queue will write the PHY to disable and clear the
 525          * interrupt, and then reenable the irq line. */
 526         disable_irq_nosync(irq);
 527         atomic_inc(&phydev->irq_disable);
 528
 529         schedule_work(&phydev->phy_queue);
 530
 531         return IRQ_HANDLED;
 532 }
 533
 534 /**
 535  * phy_enable_interrupts - Enable the interrupts from the PHY side
 536  * @phydev: target phy_device struct
 537  */
 538 static int phy_enable_interrupts(struct phy_device *phydev)
 539 {
 540         int err;
 541
 542         err = phy_clear_interrupt(phydev);
 543
 544         if (err < 0)
 545                 return err;
 546
 547         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 548
 549         return err;
 550 }
 551
 552 /**
 553  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
 554  * @phydev: target phy_device struct
 555  */
 556 static int phy_disable_interrupts(struct phy_device *phydev)
 557 {
 558         int err;
 559
 560         /* Disable PHY interrupts */
 561         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 562
 563         if (err)
 564                 goto phy_err;
 565
 566         /* Clear the interrupt */
 567         err = phy_clear_interrupt(phydev);
 568
 569         if (err)
 570                 goto phy_err;
 571
 572         return 0;
 573
 574 phy_err:
 575         phy_error(phydev);
 576
 577         return err;
 578 }
 579
 580 /**
 581  * phy_start_interrupts - request and enable interrupts for a PHY device
 582  * @phydev: target phy_device struct
 583  *
 584  * Description: Request the interrupt for the given PHY.
 585  *   If this fails, then we set irq to PHY_POLL.
 586  *   Otherwise, we enable the interrupts in the PHY.
 587  *   This should only be called with a valid IRQ number.
 588  *   Returns 0 on success or < 0 on error.
 589  */
 590 int phy_start_interrupts(struct phy_device *phydev)
 591 {
 592         int err = 0;
 593
 594         INIT_WORK(&phydev->phy_queue, phy_change);
 595
 596         atomic_set(&phydev->irq_disable, 0);
 597         if (request_irq(phydev->irq, phy_interrupt,
 598                                 IRQF_SHARED,
 599                                 "phy_interrupt",
 600                                 phydev) < 0) {
 601                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 602                                 phydev->bus->name,
 603                                 phydev->irq);
 604                 phydev->irq = PHY_POLL;
 605                 return 0;
 606         }
 607
 608         err = phy_enable_interrupts(phydev);
 609
 610         return err;
 611 }
 612 EXPORT_SYMBOL(phy_start_interrupts);
 613
 614 /**
 615  * phy_stop_interrupts - disable interrupts from a PHY device
 616  * @phydev: target phy_device struct
 617  */
 618 int phy_stop_interrupts(struct phy_device *phydev)
 619 {
 620         int err;
 621
 622         err = phy_disable_interrupts(phydev);
 623
 624         if (err)
 625                 phy_error(phydev);
 626
 627         free_irq(phydev->irq, phydev);
 628
 629         /*
 630          * Cannot call flush_scheduled_work() here as desired because
 631          * of rtnl_lock(), but we do not really care about what would
 632          * be done, except from enable_irq(), so cancel any work
 633          * possibly pending and take care of the matter below.
 634          */
 635         cancel_work_sync(&phydev->phy_queue);
 636         /*
 637          * If work indeed has been cancelled, disable_irq() will have
 638          * been left unbalanced from phy_interrupt() and enable_irq()
 639          * has to be called so that other devices on the line work.
 640          */
 641         while (atomic_dec_return(&phydev->irq_disable) >= 0)
 642                 enable_irq(phydev->irq);
 643
 644         return err;
 645 }
 646 EXPORT_SYMBOL(phy_stop_interrupts);
 647
 648
 649 /**
 650  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
 651  * @work: work_struct that describes the work to be done
 652  */
 653 static void phy_change(struct work_struct *work)
 654 {
 655         int err;
 656         struct phy_device *phydev =
 657                 container_of(work, struct phy_device, phy_queue);
 658
 659         if (phydev->drv->did_interrupt &&
 660             !phydev->drv->did_interrupt(phydev))
 661                 goto ignore;
 662
 663         err = phy_disable_interrupts(phydev);
 664
 665         if (err)
 666                 goto phy_err;
 667
 668         mutex_lock(&phydev->lock);
 669         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 670                 phydev->state = PHY_CHANGELINK;
 671         mutex_unlock(&phydev->lock);
 672
 673         atomic_dec(&phydev->irq_disable);
 674         enable_irq(phydev->irq);
 675
 676         /* Reenable interrupts */
 677         if (PHY_HALTED != phydev->state)
 678                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 679
 680         if (err)
 681                 goto irq_enable_err;
 682
 683         /* reschedule state queue work to run as soon as possible */
 684         cancel_delayed_work_sync(&phydev->state_queue);
 685         schedule_delayed_work(&phydev->state_queue, 0);
 686
 687         return;
 688
 689 ignore:
 690         atomic_dec(&phydev->irq_disable);
 691         enable_irq(phydev->irq);
 692         return;
 693
 694 irq_enable_err:
 695         disable_irq(phydev->irq);
 696         atomic_inc(&phydev->irq_disable);
 697 phy_err:
 698         phy_error(phydev);
 699 }
 700
 701 /**
 702  * phy_stop - Bring down the PHY link, and stop checking the status
 703  * @phydev: target phy_device struct
 704  */
 705 void phy_stop(struct phy_device *phydev)
 706 {
 707         mutex_lock(&phydev->lock);
 708
 709         if (PHY_HALTED == phydev->state)
 710                 goto out_unlock;
 711
 712         if (phydev->irq != PHY_POLL) {
 713                 /* Disable PHY Interrupts */
 714                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 715
 716                 /* Clear any pending interrupts */
 717                 phy_clear_interrupt(phydev);
 718         }
 719
 720         phydev->state = PHY_HALTED;
 721
 722 out_unlock:
 723         mutex_unlock(&phydev->lock);
 724
 725         /*
 726          * Cannot call flush_scheduled_work() here as desired because
 727          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
 728          * will not reenable interrupts.
 729          */
 730 }
 731
 732
 733 /**
 734  * phy_start - start or restart a PHY device
 735  * @phydev: target phy_device struct
 736  *
 737  * Description: Indicates the attached device's readiness to
 738  *   handle PHY-related work.  Used during startup to start the
 739  *   PHY, and after a call to phy_stop() to resume operation.
 740  *   Also used to indicate the MDIO bus has cleared an error
 741  *   condition.
 742  */
 743 void phy_start(struct phy_device *phydev)
 744 {
 745         mutex_lock(&phydev->lock);
 746
 747         switch (phydev->state) {
 748                 case PHY_STARTING:
 749                         phydev->state = PHY_PENDING;
 750                         break;
 751                 case PHY_READY:
 752                         phydev->state = PHY_UP;
 753                         break;
 754                 case PHY_HALTED:
 755                         phydev->state = PHY_RESUMING;
 756                 default:
 757                         break;
 758         }
 759         mutex_unlock(&phydev->lock);
 760 }
 761 EXPORT_SYMBOL(phy_stop);
 762 EXPORT_SYMBOL(phy_start);
 763
 764 /**
 765  * phy_state_machine - Handle the state machine
 766  * @work: work_struct that describes the work to be done
 767  */
 768 void phy_state_machine(struct work_struct *work)
 769 {
 770         struct delayed_work *dwork = to_delayed_work(work);
 771         struct phy_device *phydev =
 772                         container_of(dwork, struct phy_device, state_queue);
 773         int needs_aneg = 0;
 774         int err = 0;
 775
 776         mutex_lock(&phydev->lock);
 777
 778         if (phydev->adjust_state)
 779                 phydev->adjust_state(phydev->attached_dev);
 780
 781         switch(phydev->state) {
 782                 case PHY_DOWN:
 783                 case PHY_STARTING:
 784                 case PHY_READY:
 785                 case PHY_PENDING:
 786                         break;
 787                 case PHY_UP:
 788                         needs_aneg = 1;
 789
 790                         phydev->link_timeout = PHY_AN_TIMEOUT;
 791
 792                         break;
 793                 case PHY_AN:
 794                         err = phy_read_status(phydev);
 795
 796                         if (err < 0)
 797                                 break;
 798
 799                         /* If the link is down, give up on
 800                          * negotiation for now */
 801                         if (!phydev->link) {
 802                                 phydev->state = PHY_NOLINK;
 803                                 netif_carrier_off(phydev->attached_dev);
 804                                 phydev->adjust_link(phydev->attached_dev);
 805                                 break;
 806                         }
 807
 808                         /* Check if negotiation is done.  Break
 809                          * if there's an error */
 810                         err = phy_aneg_done(phydev);
 811                         if (err < 0)
 812                                 break;
 813
 814                         /* If AN is done, we're running */
 815                         if (err > 0) {
 816                                 phydev->state = PHY_RUNNING;
 817                                 netif_carrier_on(phydev->attached_dev);
 818                                 phydev->adjust_link(phydev->attached_dev);
 819
 820                         } else if (0 == phydev->link_timeout--) {
 821                                 int idx;
 822
 823                                 needs_aneg = 1;
 824                                 /* If we have the magic_aneg bit,
 825                                  * we try again */
 826                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
 827                                         break;
 828
 829                                 /* The timer expired, and we still
 830                                  * don't have a setting, so we try
 831                                  * forcing it until we find one that
 832                                  * works, starting from the fastest speed,
 833                                  * and working our way down */
 834                                 idx = phy_find_valid(0, phydev->supported);
 835
 836                                 phydev->speed = settings[idx].speed;
 837                                 phydev->duplex = settings[idx].duplex;
 838
 839                                 phydev->autoneg = AUTONEG_DISABLE;
 840
 841                                 pr_info("Trying %d/%s\n", phydev->speed,
 842                                                 DUPLEX_FULL ==
 843                                                 phydev->duplex ?
 844                                                 "FULL" : "HALF");
 845                         }
 846                         break;
 847                 case PHY_NOLINK:
 848                         err = phy_read_status(phydev);
 849
 850                         if (err)
 851                                 break;
 852
 853                         if (phydev->link) {
 854                                 phydev->state = PHY_RUNNING;
 855                                 netif_carrier_on(phydev->attached_dev);
 856                                 phydev->adjust_link(phydev->attached_dev);
 857                         }
 858                         break;
 859                 case PHY_FORCING:
 860                         err = genphy_update_link(phydev);
 861
 862                         if (err)
 863                                 break;
 864
 865                         if (phydev->link) {
 866                                 phydev->state = PHY_RUNNING;
 867                                 netif_carrier_on(phydev->attached_dev);
 868                         } else {
 869                                 if (0 == phydev->link_timeout--) {
 870                                         phy_force_reduction(phydev);
 871                                         needs_aneg = 1;
 872                                 }
 873                         }
 874
 875                         phydev->adjust_link(phydev->attached_dev);
 876                         break;
 877                 case PHY_RUNNING:
 878                         /* Only register a CHANGE if we are
 879                          * polling */
 880                         if (PHY_POLL == phydev->irq)
 881                                 phydev->state = PHY_CHANGELINK;
 882                         break;
 883                 case PHY_CHANGELINK:
 884                         err = phy_read_status(phydev);
 885
 886                         if (err)
 887                                 break;
 888
 889                         if (phydev->link) {
 890                                 phydev->state = PHY_RUNNING;
 891                                 netif_carrier_on(phydev->attached_dev);
 892                         } else {
 893                                 phydev->state = PHY_NOLINK;
 894                                 netif_carrier_off(phydev->attached_dev);
 895                         }
 896
 897                         phydev->adjust_link(phydev->attached_dev);
 898
 899                         if (PHY_POLL != phydev->irq)
 900                                 err = phy_config_interrupt(phydev,
 901                                                 PHY_INTERRUPT_ENABLED);
 902                         break;
 903                 case PHY_HALTED:
 904                         if (phydev->link) {
 905                                 phydev->link = 0;
 906                                 netif_carrier_off(phydev->attached_dev);
 907                                 phydev->adjust_link(phydev->attached_dev);
 908                         }
 909                         break;
 910                 case PHY_RESUMING:
 911
 912                         err = phy_clear_interrupt(phydev);
 913
 914                         if (err)
 915                                 break;
 916
 917                         err = phy_config_interrupt(phydev,
 918                                         PHY_INTERRUPT_ENABLED);
 919
 920                         if (err)
 921                                 break;
 922
 923                         if (AUTONEG_ENABLE == phydev->autoneg) {
 924                                 err = phy_aneg_done(phydev);
 925                                 if (err < 0)
 926                                         break;
 927
 928                                 /* err > 0 if AN is done.
 929                                  * Otherwise, it's 0, and we're
 930                                  * still waiting for AN */
 931                                 if (err > 0) {
 932                                         err = phy_read_status(phydev);
 933                                         if (err)
 934                                                 break;
 935
 936                                         if (phydev->link) {
 937                                                 phydev->state = PHY_RUNNING;
 938                                                 netif_carrier_on(phydev->attached_dev);
 939                                         } else
 940                                                 phydev->state = PHY_NOLINK;
 941                                         phydev->adjust_link(phydev->attached_dev);
 942                                 } else {
 943                                         phydev->state = PHY_AN;
 944                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 945                                 }
 946                         } else {
 947                                 err = phy_read_status(phydev);
 948                                 if (err)
 949                                         break;
 950
 951                                 if (phydev->link) {
 952                                         phydev->state = PHY_RUNNING;
 953                                         netif_carrier_on(phydev->attached_dev);
 954                                 } else
 955                                         phydev->state = PHY_NOLINK;
 956                                 phydev->adjust_link(phydev->attached_dev);
 957                         }
 958                         break;
 959         }
 960
 961         mutex_unlock(&phydev->lock);
 962
 963         if (needs_aneg)
 964                 err = phy_start_aneg(phydev);
 965
 966         if (err < 0)
 967                 phy_error(phydev);
 968
 969         schedule_delayed_work(&phydev->state_queue, PHY_STATE_TIME * HZ);
 970 }