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 (!capable(CAP_NET_ADMIN))
 328                         return -EPERM;
 329
 330                 if (mii_data->phy_id == phydev->addr) {
 331                         switch(mii_data->reg_num) {
 332                         case MII_BMCR:
 333                                 if ((val & (BMCR_RESET|BMCR_ANENABLE)) == 0)
 334                                         phydev->autoneg = AUTONEG_DISABLE;
 335                                 else
 336                                         phydev->autoneg = AUTONEG_ENABLE;
 337                                 if ((!phydev->autoneg) && (val & BMCR_FULLDPLX))
 338                                         phydev->duplex = DUPLEX_FULL;
 339                                 else
 340                                         phydev->duplex = DUPLEX_HALF;
 341                                 if ((!phydev->autoneg) &&
 342                                                 (val & BMCR_SPEED1000))
 343                                         phydev->speed = SPEED_1000;
 344                                 else if ((!phydev->autoneg) &&
 345                                                 (val & BMCR_SPEED100))
 346                                         phydev->speed = SPEED_100;
 347                                 break;
 348                         case MII_ADVERTISE:
 349                                 phydev->advertising = val;
 350                                 break;
 351                         default:
 352                                 /* do nothing */
 353                                 break;
 354                         }
 355                 }
 356
 357                 phy_write(phydev, 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         default:
 368                 return -EOPNOTSUPP;
 369         }
 370
 371         return 0;
 372 }
 373 EXPORT_SYMBOL(phy_mii_ioctl);
 374
 375 /**
 376  * phy_start_aneg - start auto-negotiation for this PHY device
 377  * @phydev: the phy_device struct
 378  *
 379  * Description: Sanitizes the settings (if we're not autonegotiating
 380  *   them), and then calls the driver's config_aneg function.
 381  *   If the PHYCONTROL Layer is operating, we change the state to
 382  *   reflect the beginning of Auto-negotiation or forcing.
 383  */
 384 int phy_start_aneg(struct phy_device *phydev)
 385 {
 386         int err;
 387
 388         mutex_lock(&phydev->lock);
 389
 390         if (AUTONEG_DISABLE == phydev->autoneg)
 391                 phy_sanitize_settings(phydev);
 392
 393         err = phydev->drv->config_aneg(phydev);
 394
 395         if (err < 0)
 396                 goto out_unlock;
 397
 398         if (phydev->state != PHY_HALTED) {
 399                 if (AUTONEG_ENABLE == phydev->autoneg) {
 400                         phydev->state = PHY_AN;
 401                         phydev->link_timeout = PHY_AN_TIMEOUT;
 402                 } else {
 403                         phydev->state = PHY_FORCING;
 404                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
 405                 }
 406         }
 407
 408 out_unlock:
 409         mutex_unlock(&phydev->lock);
 410         return err;
 411 }
 412 EXPORT_SYMBOL(phy_start_aneg);
 413
 414
 415 static void phy_change(struct work_struct *work);
 416 static void phy_state_machine(struct work_struct *work);
 417
 418 /**
 419  * phy_start_machine - start PHY state machine tracking
 420  * @phydev: the phy_device struct
 421  * @handler: callback function for state change notifications
 422  *
 423  * Description: The PHY infrastructure can run a state machine
 424  *   which tracks whether the PHY is starting up, negotiating,
 425  *   etc.  This function starts the timer which tracks the state
 426  *   of the PHY.  If you want to be notified when the state changes,
 427  *   pass in the callback @handler, otherwise, pass NULL.  If you
 428  *   want to maintain your own state machine, do not call this
 429  *   function.
 430  */
 431 void phy_start_machine(struct phy_device *phydev,
 432                 void (*handler)(struct net_device *))
 433 {
 434         phydev->adjust_state = handler;
 435
 436         INIT_DELAYED_WORK(&phydev->state_queue, phy_state_machine);
 437         schedule_delayed_work(&phydev->state_queue, jiffies + HZ);
 438 }
 439
 440 /**
 441  * phy_stop_machine - stop the PHY state machine tracking
 442  * @phydev: target phy_device struct
 443  *
 444  * Description: Stops the state machine timer, sets the state to UP
 445  *   (unless it wasn't up yet). This function must be called BEFORE
 446  *   phy_detach.
 447  */
 448 void phy_stop_machine(struct phy_device *phydev)
 449 {
 450         cancel_delayed_work_sync(&phydev->state_queue);
 451
 452         mutex_lock(&phydev->lock);
 453         if (phydev->state > PHY_UP)
 454                 phydev->state = PHY_UP;
 455         mutex_unlock(&phydev->lock);
 456
 457         phydev->adjust_state = NULL;
 458 }
 459
 460 /**
 461  * phy_force_reduction - reduce PHY speed/duplex settings by one step
 462  * @phydev: target phy_device struct
 463  *
 464  * Description: Reduces the speed/duplex settings by one notch,
 465  *   in this order--
 466  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 467  *   The function bottoms out at 10/HALF.
 468  */
 469 static void phy_force_reduction(struct phy_device *phydev)
 470 {
 471         int idx;
 472
 473         idx = phy_find_setting(phydev->speed, phydev->duplex);
 474
 475         idx++;
 476
 477         idx = phy_find_valid(idx, phydev->supported);
 478
 479         phydev->speed = settings[idx].speed;
 480         phydev->duplex = settings[idx].duplex;
 481
 482         pr_info("Trying %d/%s\n", phydev->speed,
 483                         DUPLEX_FULL == phydev->duplex ?
 484                         "FULL" : "HALF");
 485 }
 486
 487
 488 /**
 489  * phy_error - enter HALTED state for this PHY device
 490  * @phydev: target phy_device struct
 491  *
 492  * Moves the PHY to the HALTED state in response to a read
 493  * or write error, and tells the controller the link is down.
 494  * Must not be called from interrupt context, or while the
 495  * phydev->lock is held.
 496  */
 497 static void phy_error(struct phy_device *phydev)
 498 {
 499         mutex_lock(&phydev->lock);
 500         phydev->state = PHY_HALTED;
 501         mutex_unlock(&phydev->lock);
 502 }
 503
 504 /**
 505  * phy_interrupt - PHY interrupt handler
 506  * @irq: interrupt line
 507  * @phy_dat: phy_device pointer
 508  *
 509  * Description: When a PHY interrupt occurs, the handler disables
 510  * interrupts, and schedules a work task to clear the interrupt.
 511  */
 512 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 513 {
 514         struct phy_device *phydev = phy_dat;
 515
 516         if (PHY_HALTED == phydev->state)
 517                 return IRQ_NONE;                /* It can't be ours.  */
 518
 519         /* The MDIO bus is not allowed to be written in interrupt
 520          * context, so we need to disable the irq here.  A work
 521          * queue will write the PHY to disable and clear the
 522          * interrupt, and then reenable the irq line. */
 523         disable_irq_nosync(irq);
 524         atomic_inc(&phydev->irq_disable);
 525
 526         schedule_work(&phydev->phy_queue);
 527
 528         return IRQ_HANDLED;
 529 }
 530
 531 /**
 532  * phy_enable_interrupts - Enable the interrupts from the PHY side
 533  * @phydev: target phy_device struct
 534  */
 535 int phy_enable_interrupts(struct phy_device *phydev)
 536 {
 537         int err;
 538
 539         err = phy_clear_interrupt(phydev);
 540
 541         if (err < 0)
 542                 return err;
 543
 544         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 545
 546         return err;
 547 }
 548 EXPORT_SYMBOL(phy_enable_interrupts);
 549
 550 /**
 551  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
 552  * @phydev: target phy_device struct
 553  */
 554 int phy_disable_interrupts(struct phy_device *phydev)
 555 {
 556         int err;
 557
 558         /* Disable PHY interrupts */
 559         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 560
 561         if (err)
 562                 goto phy_err;
 563
 564         /* Clear the interrupt */
 565         err = phy_clear_interrupt(phydev);
 566
 567         if (err)
 568                 goto phy_err;
 569
 570         return 0;
 571
 572 phy_err:
 573         phy_error(phydev);
 574
 575         return err;
 576 }
 577 EXPORT_SYMBOL(phy_disable_interrupts);
 578
 579 /**
 580  * phy_start_interrupts - request and enable interrupts for a PHY device
 581  * @phydev: target phy_device struct
 582  *
 583  * Description: Request the interrupt for the given PHY.
 584  *   If this fails, then we set irq to PHY_POLL.
 585  *   Otherwise, we enable the interrupts in the PHY.
 586  *   This should only be called with a valid IRQ number.
 587  *   Returns 0 on success or < 0 on error.
 588  */
 589 int phy_start_interrupts(struct phy_device *phydev)
 590 {
 591         int err = 0;
 592
 593         INIT_WORK(&phydev->phy_queue, phy_change);
 594
 595         atomic_set(&phydev->irq_disable, 0);
 596         if (request_irq(phydev->irq, phy_interrupt,
 597                                 IRQF_SHARED,
 598                                 "phy_interrupt",
 599                                 phydev) < 0) {
 600                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 601                                 phydev->bus->name,
 602                                 phydev->irq);
 603                 phydev->irq = PHY_POLL;
 604                 return 0;
 605         }
 606
 607         err = phy_enable_interrupts(phydev);
 608
 609         return err;
 610 }
 611 EXPORT_SYMBOL(phy_start_interrupts);
 612
 613 /**
 614  * phy_stop_interrupts - disable interrupts from a PHY device
 615  * @phydev: target phy_device struct
 616  */
 617 int phy_stop_interrupts(struct phy_device *phydev)
 618 {
 619         int err;
 620
 621         err = phy_disable_interrupts(phydev);
 622
 623         if (err)
 624                 phy_error(phydev);
 625
 626         free_irq(phydev->irq, phydev);
 627
 628         /*
 629          * Cannot call flush_scheduled_work() here as desired because
 630          * of rtnl_lock(), but we do not really care about what would
 631          * be done, except from enable_irq(), so cancel any work
 632          * possibly pending and take care of the matter below.
 633          */
 634         cancel_work_sync(&phydev->phy_queue);
 635         /*
 636          * If work indeed has been cancelled, disable_irq() will have
 637          * been left unbalanced from phy_interrupt() and enable_irq()
 638          * has to be called so that other devices on the line work.
 639          */
 640         while (atomic_dec_return(&phydev->irq_disable) >= 0)
 641                 enable_irq(phydev->irq);
 642
 643         return err;
 644 }
 645 EXPORT_SYMBOL(phy_stop_interrupts);
 646
 647
 648 /**
 649  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
 650  * @work: work_struct that describes the work to be done
 651  */
 652 static void phy_change(struct work_struct *work)
 653 {
 654         int err;
 655         struct phy_device *phydev =
 656                 container_of(work, struct phy_device, phy_queue);
 657
 658         err = phy_disable_interrupts(phydev);
 659
 660         if (err)
 661                 goto phy_err;
 662
 663         mutex_lock(&phydev->lock);
 664         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 665                 phydev->state = PHY_CHANGELINK;
 666         mutex_unlock(&phydev->lock);
 667
 668         atomic_dec(&phydev->irq_disable);
 669         enable_irq(phydev->irq);
 670
 671         /* Reenable interrupts */
 672         if (PHY_HALTED != phydev->state)
 673                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 674
 675         if (err)
 676                 goto irq_enable_err;
 677
 678         /* reschedule state queue work to run as soon as possible */
 679         cancel_delayed_work_sync(&phydev->state_queue);
 680         schedule_delayed_work(&phydev->state_queue, 0);
 681
 682         return;
 683
 684 irq_enable_err:
 685         disable_irq(phydev->irq);
 686         atomic_inc(&phydev->irq_disable);
 687 phy_err:
 688         phy_error(phydev);
 689 }
 690
 691 /**
 692  * phy_stop - Bring down the PHY link, and stop checking the status
 693  * @phydev: target phy_device struct
 694  */
 695 void phy_stop(struct phy_device *phydev)
 696 {
 697         mutex_lock(&phydev->lock);
 698
 699         if (PHY_HALTED == phydev->state)
 700                 goto out_unlock;
 701
 702         if (phydev->irq != PHY_POLL) {
 703                 /* Disable PHY Interrupts */
 704                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 705
 706                 /* Clear any pending interrupts */
 707                 phy_clear_interrupt(phydev);
 708         }
 709
 710         phydev->state = PHY_HALTED;
 711
 712 out_unlock:
 713         mutex_unlock(&phydev->lock);
 714
 715         /*
 716          * Cannot call flush_scheduled_work() here as desired because
 717          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
 718          * will not reenable interrupts.
 719          */
 720 }
 721
 722
 723 /**
 724  * phy_start - start or restart a PHY device
 725  * @phydev: target phy_device struct
 726  *
 727  * Description: Indicates the attached device's readiness to
 728  *   handle PHY-related work.  Used during startup to start the
 729  *   PHY, and after a call to phy_stop() to resume operation.
 730  *   Also used to indicate the MDIO bus has cleared an error
 731  *   condition.
 732  */
 733 void phy_start(struct phy_device *phydev)
 734 {
 735         mutex_lock(&phydev->lock);
 736
 737         switch (phydev->state) {
 738                 case PHY_STARTING:
 739                         phydev->state = PHY_PENDING;
 740                         break;
 741                 case PHY_READY:
 742                         phydev->state = PHY_UP;
 743                         break;
 744                 case PHY_HALTED:
 745                         phydev->state = PHY_RESUMING;
 746                 default:
 747                         break;
 748         }
 749         mutex_unlock(&phydev->lock);
 750 }
 751 EXPORT_SYMBOL(phy_stop);
 752 EXPORT_SYMBOL(phy_start);
 753
 754 /**
 755  * phy_state_machine - Handle the state machine
 756  * @work: work_struct that describes the work to be done
 757  */
 758 static void phy_state_machine(struct work_struct *work)
 759 {
 760         struct delayed_work *dwork = to_delayed_work(work);
 761         struct phy_device *phydev =
 762                         container_of(dwork, struct phy_device, state_queue);
 763         int needs_aneg = 0;
 764         int err = 0;
 765
 766         mutex_lock(&phydev->lock);
 767
 768         if (phydev->adjust_state)
 769                 phydev->adjust_state(phydev->attached_dev);
 770
 771         switch(phydev->state) {
 772                 case PHY_DOWN:
 773                 case PHY_STARTING:
 774                 case PHY_READY:
 775                 case PHY_PENDING:
 776                         break;
 777                 case PHY_UP:
 778                         needs_aneg = 1;
 779
 780                         phydev->link_timeout = PHY_AN_TIMEOUT;
 781
 782                         break;
 783                 case PHY_AN:
 784                         err = phy_read_status(phydev);
 785
 786                         if (err < 0)
 787                                 break;
 788
 789                         /* If the link is down, give up on
 790                          * negotiation for now */
 791                         if (!phydev->link) {
 792                                 phydev->state = PHY_NOLINK;
 793                                 netif_carrier_off(phydev->attached_dev);
 794                                 phydev->adjust_link(phydev->attached_dev);
 795                                 break;
 796                         }
 797
 798                         /* Check if negotiation is done.  Break
 799                          * if there's an error */
 800                         err = phy_aneg_done(phydev);
 801                         if (err < 0)
 802                                 break;
 803
 804                         /* If AN is done, we're running */
 805                         if (err > 0) {
 806                                 phydev->state = PHY_RUNNING;
 807                                 netif_carrier_on(phydev->attached_dev);
 808                                 phydev->adjust_link(phydev->attached_dev);
 809
 810                         } else if (0 == phydev->link_timeout--) {
 811                                 int idx;
 812
 813                                 needs_aneg = 1;
 814                                 /* If we have the magic_aneg bit,
 815                                  * we try again */
 816                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
 817                                         break;
 818
 819                                 /* The timer expired, and we still
 820                                  * don't have a setting, so we try
 821                                  * forcing it until we find one that
 822                                  * works, starting from the fastest speed,
 823                                  * and working our way down */
 824                                 idx = phy_find_valid(0, phydev->supported);
 825
 826                                 phydev->speed = settings[idx].speed;
 827                                 phydev->duplex = settings[idx].duplex;
 828
 829                                 phydev->autoneg = AUTONEG_DISABLE;
 830
 831                                 pr_info("Trying %d/%s\n", phydev->speed,
 832                                                 DUPLEX_FULL ==
 833                                                 phydev->duplex ?
 834                                                 "FULL" : "HALF");
 835                         }
 836                         break;
 837                 case PHY_NOLINK:
 838                         err = phy_read_status(phydev);
 839
 840                         if (err)
 841                                 break;
 842
 843                         if (phydev->link) {
 844                                 phydev->state = PHY_RUNNING;
 845                                 netif_carrier_on(phydev->attached_dev);
 846                                 phydev->adjust_link(phydev->attached_dev);
 847                         }
 848                         break;
 849                 case PHY_FORCING:
 850                         err = genphy_update_link(phydev);
 851
 852                         if (err)
 853                                 break;
 854
 855                         if (phydev->link) {
 856                                 phydev->state = PHY_RUNNING;
 857                                 netif_carrier_on(phydev->attached_dev);
 858                         } else {
 859                                 if (0 == phydev->link_timeout--) {
 860                                         phy_force_reduction(phydev);
 861                                         needs_aneg = 1;
 862                                 }
 863                         }
 864
 865                         phydev->adjust_link(phydev->attached_dev);
 866                         break;
 867                 case PHY_RUNNING:
 868                         /* Only register a CHANGE if we are
 869                          * polling */
 870                         if (PHY_POLL == phydev->irq)
 871                                 phydev->state = PHY_CHANGELINK;
 872                         break;
 873                 case PHY_CHANGELINK:
 874                         err = phy_read_status(phydev);
 875
 876                         if (err)
 877                                 break;
 878
 879                         if (phydev->link) {
 880                                 phydev->state = PHY_RUNNING;
 881                                 netif_carrier_on(phydev->attached_dev);
 882                         } else {
 883                                 phydev->state = PHY_NOLINK;
 884                                 netif_carrier_off(phydev->attached_dev);
 885                         }
 886
 887                         phydev->adjust_link(phydev->attached_dev);
 888
 889                         if (PHY_POLL != phydev->irq)
 890                                 err = phy_config_interrupt(phydev,
 891                                                 PHY_INTERRUPT_ENABLED);
 892                         break;
 893                 case PHY_HALTED:
 894                         if (phydev->link) {
 895                                 phydev->link = 0;
 896                                 netif_carrier_off(phydev->attached_dev);
 897                                 phydev->adjust_link(phydev->attached_dev);
 898                         }
 899                         break;
 900                 case PHY_RESUMING:
 901
 902                         err = phy_clear_interrupt(phydev);
 903
 904                         if (err)
 905                                 break;
 906
 907                         err = phy_config_interrupt(phydev,
 908                                         PHY_INTERRUPT_ENABLED);
 909
 910                         if (err)
 911                                 break;
 912
 913                         if (AUTONEG_ENABLE == phydev->autoneg) {
 914                                 err = phy_aneg_done(phydev);
 915                                 if (err < 0)
 916                                         break;
 917
 918                                 /* err > 0 if AN is done.
 919                                  * Otherwise, it's 0, and we're
 920                                  * still waiting for AN */
 921                                 if (err > 0) {
 922                                         phydev->state = PHY_RUNNING;
 923                                 } else {
 924                                         phydev->state = PHY_AN;
 925                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 926                                 }
 927                         } else
 928                                 phydev->state = PHY_RUNNING;
 929                         break;
 930         }
 931
 932         mutex_unlock(&phydev->lock);
 933
 934         if (needs_aneg)
 935                 err = phy_start_aneg(phydev);
 936
 937         if (err < 0)
 938                 phy_error(phydev);
 939
 940         schedule_delayed_work(&phydev->state_queue,
 941                                 jiffies + PHY_STATE_TIME * HZ);
 942 }