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 <asm/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(" - %d/%s", phydev->speed,
  51                                 DUPLEX_FULL == phydev->duplex ?
  52                                 "Full" : "Half");
  53
  54         printk("\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 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 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 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 EXPORT_SYMBOL(phy_sanitize_settings);
 227
 228 /**
 229  * phy_ethtool_sset - generic ethtool sset function, handles all the details
 230  * @phydev: target phy_device struct
 231  * @cmd: ethtool_cmd
 232  *
 233  * A few notes about parameter checking:
 234  * - We don't set port or transceiver, so we don't care what they
 235  *   were set to.
 236  * - phy_start_aneg() will make sure forced settings are sane, and
 237  *   choose the next best ones from the ones selected, so we don't
 238  *   care if ethtool tries to give us bad values.
 239  */
 240 int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 241 {
 242         if (cmd->phy_address != phydev->addr)
 243                 return -EINVAL;
 244
 245         /* We make sure that we don't pass unsupported
 246          * values in to the PHY */
 247         cmd->advertising &= phydev->supported;
 248
 249         /* Verify the settings we care about. */
 250         if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
 251                 return -EINVAL;
 252
 253         if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
 254                 return -EINVAL;
 255
 256         if (cmd->autoneg == AUTONEG_DISABLE &&
 257             ((cmd->speed != SPEED_1000 &&
 258               cmd->speed != SPEED_100 &&
 259               cmd->speed != SPEED_10) ||
 260              (cmd->duplex != DUPLEX_HALF &&
 261               cmd->duplex != DUPLEX_FULL)))
 262                 return -EINVAL;
 263
 264         phydev->autoneg = cmd->autoneg;
 265
 266         phydev->speed = cmd->speed;
 267
 268         phydev->advertising = cmd->advertising;
 269
 270         if (AUTONEG_ENABLE == cmd->autoneg)
 271                 phydev->advertising |= ADVERTISED_Autoneg;
 272         else
 273                 phydev->advertising &= ~ADVERTISED_Autoneg;
 274
 275         phydev->duplex = cmd->duplex;
 276
 277         /* Restart the PHY */
 278         phy_start_aneg(phydev);
 279
 280         return 0;
 281 }
 282 EXPORT_SYMBOL(phy_ethtool_sset);
 283
 284 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 285 {
 286         cmd->supported = phydev->supported;
 287
 288         cmd->advertising = phydev->advertising;
 289
 290         cmd->speed = phydev->speed;
 291         cmd->duplex = phydev->duplex;
 292         cmd->port = PORT_MII;
 293         cmd->phy_address = phydev->addr;
 294         cmd->transceiver = XCVR_EXTERNAL;
 295         cmd->autoneg = phydev->autoneg;
 296
 297         return 0;
 298 }
 299 EXPORT_SYMBOL(phy_ethtool_gset);
 300
 301 /**
 302  * phy_mii_ioctl - generic PHY MII ioctl interface
 303  * @phydev: the phy_device struct
 304  * @mii_data: MII ioctl data
 305  * @cmd: ioctl cmd to execute
 306  *
 307  * Note that this function is currently incompatible with the
 308  * PHYCONTROL layer.  It changes registers without regard to
 309  * current state.  Use at own risk.
 310  */
 311 int phy_mii_ioctl(struct phy_device *phydev,
 312                 struct mii_ioctl_data *mii_data, int cmd)
 313 {
 314         u16 val = mii_data->val_in;
 315
 316         switch (cmd) {
 317         case SIOCGMIIPHY:
 318                 mii_data->phy_id = phydev->addr;
 319                 /* fall through */
 320
 321         case SIOCGMIIREG:
 322                 mii_data->val_out = phy_read(phydev, mii_data->reg_num);
 323                 break;
 324
 325         case SIOCSMIIREG:
 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)) == 0)
 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                                 if ((!phydev->autoneg) &&
 338                                                 (val & BMCR_SPEED1000))
 339                                         phydev->speed = SPEED_1000;
 340                                 else if ((!phydev->autoneg) &&
 341                                                 (val & BMCR_SPEED100))
 342                                         phydev->speed = SPEED_100;
 343                                 break;
 344                         case MII_ADVERTISE:
 345                                 phydev->advertising = val;
 346                                 break;
 347                         default:
 348                                 /* do nothing */
 349                                 break;
 350                         }
 351                 }
 352
 353                 phy_write(phydev, mii_data->reg_num, val);
 354
 355                 if (mii_data->reg_num == MII_BMCR &&
 356                     val & BMCR_RESET &&
 357                     phydev->drv->config_init) {
 358                         phy_scan_fixups(phydev);
 359                         phydev->drv->config_init(phydev);
 360                 }
 361                 break;
 362
 363         default:
 364                 return -EOPNOTSUPP;
 365         }
 366
 367         return 0;
 368 }
 369 EXPORT_SYMBOL(phy_mii_ioctl);
 370
 371 /**
 372  * phy_start_aneg - start auto-negotiation for this PHY device
 373  * @phydev: the phy_device struct
 374  *
 375  * Description: Sanitizes the settings (if we're not autonegotiating
 376  *   them), and then calls the driver's config_aneg function.
 377  *   If the PHYCONTROL Layer is operating, we change the state to
 378  *   reflect the beginning of Auto-negotiation or forcing.
 379  */
 380 int phy_start_aneg(struct phy_device *phydev)
 381 {
 382         int err;
 383
 384         mutex_lock(&phydev->lock);
 385
 386         if (AUTONEG_DISABLE == phydev->autoneg)
 387                 phy_sanitize_settings(phydev);
 388
 389         err = phydev->drv->config_aneg(phydev);
 390
 391         if (err < 0)
 392                 goto out_unlock;
 393
 394         if (phydev->state != PHY_HALTED) {
 395                 if (AUTONEG_ENABLE == phydev->autoneg) {
 396                         phydev->state = PHY_AN;
 397                         phydev->link_timeout = PHY_AN_TIMEOUT;
 398                 } else {
 399                         phydev->state = PHY_FORCING;
 400                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
 401                 }
 402         }
 403
 404 out_unlock:
 405         mutex_unlock(&phydev->lock);
 406         return err;
 407 }
 408 EXPORT_SYMBOL(phy_start_aneg);
 409
 410
 411 static void phy_change(struct work_struct *work);
 412
 413 /**
 414  * phy_start_machine - start PHY state machine tracking
 415  * @phydev: the phy_device struct
 416  * @handler: callback function for state change notifications
 417  *
 418  * Description: The PHY infrastructure can run a state machine
 419  *   which tracks whether the PHY is starting up, negotiating,
 420  *   etc.  This function starts the timer which tracks the state
 421  *   of the PHY.  If you want to be notified when the state changes,
 422  *   pass in the callback @handler, otherwise, pass NULL.  If you
 423  *   want to maintain your own state machine, do not call this
 424  *   function.
 425  */
 426 void phy_start_machine(struct phy_device *phydev,
 427                 void (*handler)(struct net_device *))
 428 {
 429         phydev->adjust_state = handler;
 430
 431         schedule_delayed_work(&phydev->state_queue, HZ);
 432 }
 433
 434 /**
 435  * phy_stop_machine - stop the PHY state machine tracking
 436  * @phydev: target phy_device struct
 437  *
 438  * Description: Stops the state machine timer, sets the state to UP
 439  *   (unless it wasn't up yet). This function must be called BEFORE
 440  *   phy_detach.
 441  */
 442 void phy_stop_machine(struct phy_device *phydev)
 443 {
 444         cancel_delayed_work_sync(&phydev->state_queue);
 445
 446         mutex_lock(&phydev->lock);
 447         if (phydev->state > PHY_UP)
 448                 phydev->state = PHY_UP;
 449         mutex_unlock(&phydev->lock);
 450
 451         phydev->adjust_state = NULL;
 452 }
 453
 454 /**
 455  * phy_force_reduction - reduce PHY speed/duplex settings by one step
 456  * @phydev: target phy_device struct
 457  *
 458  * Description: Reduces the speed/duplex settings by one notch,
 459  *   in this order--
 460  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 461  *   The function bottoms out at 10/HALF.
 462  */
 463 static void phy_force_reduction(struct phy_device *phydev)
 464 {
 465         int idx;
 466
 467         idx = phy_find_setting(phydev->speed, phydev->duplex);
 468
 469         idx++;
 470
 471         idx = phy_find_valid(idx, phydev->supported);
 472
 473         phydev->speed = settings[idx].speed;
 474         phydev->duplex = settings[idx].duplex;
 475
 476         pr_info("Trying %d/%s\n", phydev->speed,
 477                         DUPLEX_FULL == phydev->duplex ?
 478                         "FULL" : "HALF");
 479 }
 480
 481
 482 /**
 483  * phy_error - enter HALTED state for this PHY device
 484  * @phydev: target phy_device struct
 485  *
 486  * Moves the PHY to the HALTED state in response to a read
 487  * or write error, and tells the controller the link is down.
 488  * Must not be called from interrupt context, or while the
 489  * phydev->lock is held.
 490  */
 491 static void phy_error(struct phy_device *phydev)
 492 {
 493         mutex_lock(&phydev->lock);
 494         phydev->state = PHY_HALTED;
 495         mutex_unlock(&phydev->lock);
 496 }
 497
 498 /**
 499  * phy_interrupt - PHY interrupt handler
 500  * @irq: interrupt line
 501  * @phy_dat: phy_device pointer
 502  *
 503  * Description: When a PHY interrupt occurs, the handler disables
 504  * interrupts, and schedules a work task to clear the interrupt.
 505  */
 506 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 507 {
 508         struct phy_device *phydev = phy_dat;
 509
 510         if (PHY_HALTED == phydev->state)
 511                 return IRQ_NONE;                /* It can't be ours.  */
 512
 513         /* The MDIO bus is not allowed to be written in interrupt
 514          * context, so we need to disable the irq here.  A work
 515          * queue will write the PHY to disable and clear the
 516          * interrupt, and then reenable the irq line. */
 517         disable_irq_nosync(irq);
 518         atomic_inc(&phydev->irq_disable);
 519
 520         schedule_work(&phydev->phy_queue);
 521
 522         return IRQ_HANDLED;
 523 }
 524
 525 /**
 526  * phy_enable_interrupts - Enable the interrupts from the PHY side
 527  * @phydev: target phy_device struct
 528  */
 529 int phy_enable_interrupts(struct phy_device *phydev)
 530 {
 531         int err;
 532
 533         err = phy_clear_interrupt(phydev);
 534
 535         if (err < 0)
 536                 return err;
 537
 538         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 539
 540         return err;
 541 }
 542 EXPORT_SYMBOL(phy_enable_interrupts);
 543
 544 /**
 545  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
 546  * @phydev: target phy_device struct
 547  */
 548 int phy_disable_interrupts(struct phy_device *phydev)
 549 {
 550         int err;
 551
 552         /* Disable PHY interrupts */
 553         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 554
 555         if (err)
 556                 goto phy_err;
 557
 558         /* Clear the interrupt */
 559         err = phy_clear_interrupt(phydev);
 560
 561         if (err)
 562                 goto phy_err;
 563
 564         return 0;
 565
 566 phy_err:
 567         phy_error(phydev);
 568
 569         return err;
 570 }
 571 EXPORT_SYMBOL(phy_disable_interrupts);
 572
 573 /**
 574  * phy_start_interrupts - request and enable interrupts for a PHY device
 575  * @phydev: target phy_device struct
 576  *
 577  * Description: Request the interrupt for the given PHY.
 578  *   If this fails, then we set irq to PHY_POLL.
 579  *   Otherwise, we enable the interrupts in the PHY.
 580  *   This should only be called with a valid IRQ number.
 581  *   Returns 0 on success or < 0 on error.
 582  */
 583 int phy_start_interrupts(struct phy_device *phydev)
 584 {
 585         int err = 0;
 586
 587         INIT_WORK(&phydev->phy_queue, phy_change);
 588
 589         atomic_set(&phydev->irq_disable, 0);
 590         if (request_irq(phydev->irq, phy_interrupt,
 591                                 IRQF_SHARED,
 592                                 "phy_interrupt",
 593                                 phydev) < 0) {
 594                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 595                                 phydev->bus->name,
 596                                 phydev->irq);
 597                 phydev->irq = PHY_POLL;
 598                 return 0;
 599         }
 600
 601         err = phy_enable_interrupts(phydev);
 602
 603         return err;
 604 }
 605 EXPORT_SYMBOL(phy_start_interrupts);
 606
 607 /**
 608  * phy_stop_interrupts - disable interrupts from a PHY device
 609  * @phydev: target phy_device struct
 610  */
 611 int phy_stop_interrupts(struct phy_device *phydev)
 612 {
 613         int err;
 614
 615         err = phy_disable_interrupts(phydev);
 616
 617         if (err)
 618                 phy_error(phydev);
 619
 620         free_irq(phydev->irq, phydev);
 621
 622         /*
 623          * Cannot call flush_scheduled_work() here as desired because
 624          * of rtnl_lock(), but we do not really care about what would
 625          * be done, except from enable_irq(), so cancel any work
 626          * possibly pending and take care of the matter below.
 627          */
 628         cancel_work_sync(&phydev->phy_queue);
 629         /*
 630          * If work indeed has been cancelled, disable_irq() will have
 631          * been left unbalanced from phy_interrupt() and enable_irq()
 632          * has to be called so that other devices on the line work.
 633          */
 634         while (atomic_dec_return(&phydev->irq_disable) >= 0)
 635                 enable_irq(phydev->irq);
 636
 637         return err;
 638 }
 639 EXPORT_SYMBOL(phy_stop_interrupts);
 640
 641
 642 /**
 643  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
 644  * @work: work_struct that describes the work to be done
 645  */
 646 static void phy_change(struct work_struct *work)
 647 {
 648         int err;
 649         struct phy_device *phydev =
 650                 container_of(work, struct phy_device, phy_queue);
 651
 652         if (phydev->drv->did_interrupt &&
 653             !phydev->drv->did_interrupt(phydev))
 654                 goto ignore;
 655
 656         err = phy_disable_interrupts(phydev);
 657
 658         if (err)
 659                 goto phy_err;
 660
 661         mutex_lock(&phydev->lock);
 662         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 663                 phydev->state = PHY_CHANGELINK;
 664         mutex_unlock(&phydev->lock);
 665
 666         atomic_dec(&phydev->irq_disable);
 667         enable_irq(phydev->irq);
 668
 669         /* Reenable interrupts */
 670         if (PHY_HALTED != phydev->state)
 671                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 672
 673         if (err)
 674                 goto irq_enable_err;
 675
 676         /* reschedule state queue work to run as soon as possible */
 677         cancel_delayed_work_sync(&phydev->state_queue);
 678         schedule_delayed_work(&phydev->state_queue, 0);
 679
 680         return;
 681
 682 ignore:
 683         atomic_dec(&phydev->irq_disable);
 684         enable_irq(phydev->irq);
 685         return;
 686
 687 irq_enable_err:
 688         disable_irq(phydev->irq);
 689         atomic_inc(&phydev->irq_disable);
 690 phy_err:
 691         phy_error(phydev);
 692 }
 693
 694 /**
 695  * phy_stop - Bring down the PHY link, and stop checking the status
 696  * @phydev: target phy_device struct
 697  */
 698 void phy_stop(struct phy_device *phydev)
 699 {
 700         mutex_lock(&phydev->lock);
 701
 702         if (PHY_HALTED == phydev->state)
 703                 goto out_unlock;
 704
 705         if (phydev->irq != PHY_POLL) {
 706                 /* Disable PHY Interrupts */
 707                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 708
 709                 /* Clear any pending interrupts */
 710                 phy_clear_interrupt(phydev);
 711         }
 712
 713         phydev->state = PHY_HALTED;
 714
 715 out_unlock:
 716         mutex_unlock(&phydev->lock);
 717
 718         /*
 719          * Cannot call flush_scheduled_work() here as desired because
 720          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
 721          * will not reenable interrupts.
 722          */
 723 }
 724
 725
 726 /**
 727  * phy_start - start or restart a PHY device
 728  * @phydev: target phy_device struct
 729  *
 730  * Description: Indicates the attached device's readiness to
 731  *   handle PHY-related work.  Used during startup to start the
 732  *   PHY, and after a call to phy_stop() to resume operation.
 733  *   Also used to indicate the MDIO bus has cleared an error
 734  *   condition.
 735  */
 736 void phy_start(struct phy_device *phydev)
 737 {
 738         mutex_lock(&phydev->lock);
 739
 740         switch (phydev->state) {
 741                 case PHY_STARTING:
 742                         phydev->state = PHY_PENDING;
 743                         break;
 744                 case PHY_READY:
 745                         phydev->state = PHY_UP;
 746                         break;
 747                 case PHY_HALTED:
 748                         phydev->state = PHY_RESUMING;
 749                 default:
 750                         break;
 751         }
 752         mutex_unlock(&phydev->lock);
 753 }
 754 EXPORT_SYMBOL(phy_stop);
 755 EXPORT_SYMBOL(phy_start);
 756
 757 /**
 758  * phy_state_machine - Handle the state machine
 759  * @work: work_struct that describes the work to be done
 760  */
 761 void phy_state_machine(struct work_struct *work)
 762 {
 763         struct delayed_work *dwork = to_delayed_work(work);
 764         struct phy_device *phydev =
 765                         container_of(dwork, struct phy_device, state_queue);
 766         int needs_aneg = 0;
 767         int err = 0;
 768
 769         mutex_lock(&phydev->lock);
 770
 771         if (phydev->adjust_state)
 772                 phydev->adjust_state(phydev->attached_dev);
 773
 774         switch(phydev->state) {
 775                 case PHY_DOWN:
 776                 case PHY_STARTING:
 777                 case PHY_READY:
 778                 case PHY_PENDING:
 779                         break;
 780                 case PHY_UP:
 781                         needs_aneg = 1;
 782
 783                         phydev->link_timeout = PHY_AN_TIMEOUT;
 784
 785                         break;
 786                 case PHY_AN:
 787                         err = phy_read_status(phydev);
 788
 789                         if (err < 0)
 790                                 break;
 791
 792                         /* If the link is down, give up on
 793                          * negotiation for now */
 794                         if (!phydev->link) {
 795                                 phydev->state = PHY_NOLINK;
 796                                 netif_carrier_off(phydev->attached_dev);
 797                                 phydev->adjust_link(phydev->attached_dev);
 798                                 break;
 799                         }
 800
 801                         /* Check if negotiation is done.  Break
 802                          * if there's an error */
 803                         err = phy_aneg_done(phydev);
 804                         if (err < 0)
 805                                 break;
 806
 807                         /* If AN is done, we're running */
 808                         if (err > 0) {
 809                                 phydev->state = PHY_RUNNING;
 810                                 netif_carrier_on(phydev->attached_dev);
 811                                 phydev->adjust_link(phydev->attached_dev);
 812
 813                         } else if (0 == phydev->link_timeout--) {
 814                                 int idx;
 815
 816                                 needs_aneg = 1;
 817                                 /* If we have the magic_aneg bit,
 818                                  * we try again */
 819                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
 820                                         break;
 821
 822                                 /* The timer expired, and we still
 823                                  * don't have a setting, so we try
 824                                  * forcing it until we find one that
 825                                  * works, starting from the fastest speed,
 826                                  * and working our way down */
 827                                 idx = phy_find_valid(0, phydev->supported);
 828
 829                                 phydev->speed = settings[idx].speed;
 830                                 phydev->duplex = settings[idx].duplex;
 831
 832                                 phydev->autoneg = AUTONEG_DISABLE;
 833
 834                                 pr_info("Trying %d/%s\n", phydev->speed,
 835                                                 DUPLEX_FULL ==
 836                                                 phydev->duplex ?
 837                                                 "FULL" : "HALF");
 838                         }
 839                         break;
 840                 case PHY_NOLINK:
 841                         err = phy_read_status(phydev);
 842
 843                         if (err)
 844                                 break;
 845
 846                         if (phydev->link) {
 847                                 phydev->state = PHY_RUNNING;
 848                                 netif_carrier_on(phydev->attached_dev);
 849                                 phydev->adjust_link(phydev->attached_dev);
 850                         }
 851                         break;
 852                 case PHY_FORCING:
 853                         err = genphy_update_link(phydev);
 854
 855                         if (err)
 856                                 break;
 857
 858                         if (phydev->link) {
 859                                 phydev->state = PHY_RUNNING;
 860                                 netif_carrier_on(phydev->attached_dev);
 861                         } else {
 862                                 if (0 == phydev->link_timeout--) {
 863                                         phy_force_reduction(phydev);
 864                                         needs_aneg = 1;
 865                                 }
 866                         }
 867
 868                         phydev->adjust_link(phydev->attached_dev);
 869                         break;
 870                 case PHY_RUNNING:
 871                         /* Only register a CHANGE if we are
 872                          * polling */
 873                         if (PHY_POLL == phydev->irq)
 874                                 phydev->state = PHY_CHANGELINK;
 875                         break;
 876                 case PHY_CHANGELINK:
 877                         err = phy_read_status(phydev);
 878
 879                         if (err)
 880                                 break;
 881
 882                         if (phydev->link) {
 883                                 phydev->state = PHY_RUNNING;
 884                                 netif_carrier_on(phydev->attached_dev);
 885                         } else {
 886                                 phydev->state = PHY_NOLINK;
 887                                 netif_carrier_off(phydev->attached_dev);
 888                         }
 889
 890                         phydev->adjust_link(phydev->attached_dev);
 891
 892                         if (PHY_POLL != phydev->irq)
 893                                 err = phy_config_interrupt(phydev,
 894                                                 PHY_INTERRUPT_ENABLED);
 895                         break;
 896                 case PHY_HALTED:
 897                         if (phydev->link) {
 898                                 phydev->link = 0;
 899                                 netif_carrier_off(phydev->attached_dev);
 900                                 phydev->adjust_link(phydev->attached_dev);
 901                         }
 902                         break;
 903                 case PHY_RESUMING:
 904
 905                         err = phy_clear_interrupt(phydev);
 906
 907                         if (err)
 908                                 break;
 909
 910                         err = phy_config_interrupt(phydev,
 911                                         PHY_INTERRUPT_ENABLED);
 912
 913                         if (err)
 914                                 break;
 915
 916                         if (AUTONEG_ENABLE == phydev->autoneg) {
 917                                 err = phy_aneg_done(phydev);
 918                                 if (err < 0)
 919                                         break;
 920
 921                                 /* err > 0 if AN is done.
 922                                  * Otherwise, it's 0, and we're
 923                                  * still waiting for AN */
 924                                 if (err > 0) {
 925                                         err = phy_read_status(phydev);
 926                                         if (err)
 927                                                 break;
 928
 929                                         if (phydev->link) {
 930                                                 phydev->state = PHY_RUNNING;
 931                                                 netif_carrier_on(phydev->attached_dev);
 932                                         } else
 933                                                 phydev->state = PHY_NOLINK;
 934                                         phydev->adjust_link(phydev->attached_dev);
 935                                 } else {
 936                                         phydev->state = PHY_AN;
 937                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 938                                 }
 939                         } else {
 940                                 err = phy_read_status(phydev);
 941                                 if (err)
 942                                         break;
 943
 944                                 if (phydev->link) {
 945                                         phydev->state = PHY_RUNNING;
 946                                         netif_carrier_on(phydev->attached_dev);
 947                                 } else
 948                                         phydev->state = PHY_NOLINK;
 949                                 phydev->adjust_link(phydev->attached_dev);
 950                         }
 951                         break;
 952         }
 953
 954         mutex_unlock(&phydev->lock);
 955
 956         if (needs_aneg)
 957                 err = phy_start_aneg(phydev);
 958
 959         if (err < 0)
 960                 phy_error(phydev);
 961
 962         schedule_delayed_work(&phydev->state_queue, PHY_STATE_TIME * HZ);
 963 }