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(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         if (cmd->phy_address != phydev->addr)
 242                 return -EINVAL;
 243
 244         /* We make sure that we don't pass unsupported
 245          * values in to the PHY */
 246         cmd->advertising &= phydev->supported;
 247
 248         /* Verify the settings we care about. */
 249         if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
 250                 return -EINVAL;
 251
 252         if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
 253                 return -EINVAL;
 254
 255         if (cmd->autoneg == AUTONEG_DISABLE &&
 256             ((cmd->speed != SPEED_1000 &&
 257               cmd->speed != SPEED_100 &&
 258               cmd->speed != SPEED_10) ||
 259              (cmd->duplex != DUPLEX_HALF &&
 260               cmd->duplex != DUPLEX_FULL)))
 261                 return -EINVAL;
 262
 263         phydev->autoneg = cmd->autoneg;
 264
 265         phydev->speed = cmd->speed;
 266
 267         phydev->advertising = cmd->advertising;
 268
 269         if (AUTONEG_ENABLE == cmd->autoneg)
 270                 phydev->advertising |= ADVERTISED_Autoneg;
 271         else
 272                 phydev->advertising &= ~ADVERTISED_Autoneg;
 273
 274         phydev->duplex = cmd->duplex;
 275
 276         /* Restart the PHY */
 277         phy_start_aneg(phydev);
 278
 279         return 0;
 280 }
 281 EXPORT_SYMBOL(phy_ethtool_sset);
 282
 283 int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd)
 284 {
 285         cmd->supported = phydev->supported;
 286
 287         cmd->advertising = phydev->advertising;
 288
 289         cmd->speed = phydev->speed;
 290         cmd->duplex = phydev->duplex;
 291         cmd->port = PORT_MII;
 292         cmd->phy_address = phydev->addr;
 293         cmd->transceiver = XCVR_EXTERNAL;
 294         cmd->autoneg = phydev->autoneg;
 295
 296         return 0;
 297 }
 298 EXPORT_SYMBOL(phy_ethtool_gset);
 299
 300 /**
 301  * phy_mii_ioctl - generic PHY MII ioctl interface
 302  * @phydev: the phy_device struct
 303  * @ifr: &struct ifreq for socket ioctl's
 304  * @cmd: ioctl cmd to execute
 305  *
 306  * Note that this function is currently incompatible with the
 307  * PHYCONTROL layer.  It changes registers without regard to
 308  * current state.  Use at own risk.
 309  */
 310 int phy_mii_ioctl(struct phy_device *phydev,
 311                 struct ifreq *ifr, int cmd)
 312 {
 313         struct mii_ioctl_data *mii_data = if_mii(ifr);
 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         case SIOCSHWTSTAMP:
 364                 if (phydev->drv->hwtstamp)
 365                         return phydev->drv->hwtstamp(phydev, ifr);
 366                 /* fall through */
 367
 368         default:
 369                 return -EOPNOTSUPP;
 370         }
 371
 372         return 0;
 373 }
 374 EXPORT_SYMBOL(phy_mii_ioctl);
 375
 376 /**
 377  * phy_start_aneg - start auto-negotiation for this PHY device
 378  * @phydev: the phy_device struct
 379  *
 380  * Description: Sanitizes the settings (if we're not autonegotiating
 381  *   them), and then calls the driver's config_aneg function.
 382  *   If the PHYCONTROL Layer is operating, we change the state to
 383  *   reflect the beginning of Auto-negotiation or forcing.
 384  */
 385 int phy_start_aneg(struct phy_device *phydev)
 386 {
 387         int err;
 388
 389         mutex_lock(&phydev->lock);
 390
 391         if (AUTONEG_DISABLE == phydev->autoneg)
 392                 phy_sanitize_settings(phydev);
 393
 394         err = phydev->drv->config_aneg(phydev);
 395
 396         if (err < 0)
 397                 goto out_unlock;
 398
 399         if (phydev->state != PHY_HALTED) {
 400                 if (AUTONEG_ENABLE == phydev->autoneg) {
 401                         phydev->state = PHY_AN;
 402                         phydev->link_timeout = PHY_AN_TIMEOUT;
 403                 } else {
 404                         phydev->state = PHY_FORCING;
 405                         phydev->link_timeout = PHY_FORCE_TIMEOUT;
 406                 }
 407         }
 408
 409 out_unlock:
 410         mutex_unlock(&phydev->lock);
 411         return err;
 412 }
 413 EXPORT_SYMBOL(phy_start_aneg);
 414
 415
 416 static void phy_change(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         schedule_delayed_work(&phydev->state_queue, HZ);
 437 }
 438
 439 /**
 440  * phy_stop_machine - stop the PHY state machine tracking
 441  * @phydev: target phy_device struct
 442  *
 443  * Description: Stops the state machine timer, sets the state to UP
 444  *   (unless it wasn't up yet). This function must be called BEFORE
 445  *   phy_detach.
 446  */
 447 void phy_stop_machine(struct phy_device *phydev)
 448 {
 449         cancel_delayed_work_sync(&phydev->state_queue);
 450
 451         mutex_lock(&phydev->lock);
 452         if (phydev->state > PHY_UP)
 453                 phydev->state = PHY_UP;
 454         mutex_unlock(&phydev->lock);
 455
 456         phydev->adjust_state = NULL;
 457 }
 458
 459 /**
 460  * phy_force_reduction - reduce PHY speed/duplex settings by one step
 461  * @phydev: target phy_device struct
 462  *
 463  * Description: Reduces the speed/duplex settings by one notch,
 464  *   in this order--
 465  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 466  *   The function bottoms out at 10/HALF.
 467  */
 468 static void phy_force_reduction(struct phy_device *phydev)
 469 {
 470         int idx;
 471
 472         idx = phy_find_setting(phydev->speed, phydev->duplex);
 473
 474         idx++;
 475
 476         idx = phy_find_valid(idx, phydev->supported);
 477
 478         phydev->speed = settings[idx].speed;
 479         phydev->duplex = settings[idx].duplex;
 480
 481         pr_info("Trying %d/%s\n", phydev->speed,
 482                         DUPLEX_FULL == phydev->duplex ?
 483                         "FULL" : "HALF");
 484 }
 485
 486
 487 /**
 488  * phy_error - enter HALTED state for this PHY device
 489  * @phydev: target phy_device struct
 490  *
 491  * Moves the PHY to the HALTED state in response to a read
 492  * or write error, and tells the controller the link is down.
 493  * Must not be called from interrupt context, or while the
 494  * phydev->lock is held.
 495  */
 496 static void phy_error(struct phy_device *phydev)
 497 {
 498         mutex_lock(&phydev->lock);
 499         phydev->state = PHY_HALTED;
 500         mutex_unlock(&phydev->lock);
 501 }
 502
 503 /**
 504  * phy_interrupt - PHY interrupt handler
 505  * @irq: interrupt line
 506  * @phy_dat: phy_device pointer
 507  *
 508  * Description: When a PHY interrupt occurs, the handler disables
 509  * interrupts, and schedules a work task to clear the interrupt.
 510  */
 511 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 512 {
 513         struct phy_device *phydev = phy_dat;
 514
 515         if (PHY_HALTED == phydev->state)
 516                 return IRQ_NONE;                /* It can't be ours.  */
 517
 518         /* The MDIO bus is not allowed to be written in interrupt
 519          * context, so we need to disable the irq here.  A work
 520          * queue will write the PHY to disable and clear the
 521          * interrupt, and then reenable the irq line. */
 522         disable_irq_nosync(irq);
 523         atomic_inc(&phydev->irq_disable);
 524
 525         schedule_work(&phydev->phy_queue);
 526
 527         return IRQ_HANDLED;
 528 }
 529
 530 /**
 531  * phy_enable_interrupts - Enable the interrupts from the PHY side
 532  * @phydev: target phy_device struct
 533  */
 534 static int phy_enable_interrupts(struct phy_device *phydev)
 535 {
 536         int err;
 537
 538         err = phy_clear_interrupt(phydev);
 539
 540         if (err < 0)
 541                 return err;
 542
 543         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 544
 545         return err;
 546 }
 547
 548 /**
 549  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
 550  * @phydev: target phy_device struct
 551  */
 552 static int phy_disable_interrupts(struct phy_device *phydev)
 553 {
 554         int err;
 555
 556         /* Disable PHY interrupts */
 557         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 558
 559         if (err)
 560                 goto phy_err;
 561
 562         /* Clear the interrupt */
 563         err = phy_clear_interrupt(phydev);
 564
 565         if (err)
 566                 goto phy_err;
 567
 568         return 0;
 569
 570 phy_err:
 571         phy_error(phydev);
 572
 573         return err;
 574 }
 575
 576 /**
 577  * phy_start_interrupts - request and enable interrupts for a PHY device
 578  * @phydev: target phy_device struct
 579  *
 580  * Description: Request the interrupt for the given PHY.
 581  *   If this fails, then we set irq to PHY_POLL.
 582  *   Otherwise, we enable the interrupts in the PHY.
 583  *   This should only be called with a valid IRQ number.
 584  *   Returns 0 on success or < 0 on error.
 585  */
 586 int phy_start_interrupts(struct phy_device *phydev)
 587 {
 588         int err = 0;
 589
 590         INIT_WORK(&phydev->phy_queue, phy_change);
 591
 592         atomic_set(&phydev->irq_disable, 0);
 593         if (request_irq(phydev->irq, phy_interrupt,
 594                                 IRQF_SHARED,
 595                                 "phy_interrupt",
 596                                 phydev) < 0) {
 597                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 598                                 phydev->bus->name,
 599                                 phydev->irq);
 600                 phydev->irq = PHY_POLL;
 601                 return 0;
 602         }
 603
 604         err = phy_enable_interrupts(phydev);
 605
 606         return err;
 607 }
 608 EXPORT_SYMBOL(phy_start_interrupts);
 609
 610 /**
 611  * phy_stop_interrupts - disable interrupts from a PHY device
 612  * @phydev: target phy_device struct
 613  */
 614 int phy_stop_interrupts(struct phy_device *phydev)
 615 {
 616         int err;
 617
 618         err = phy_disable_interrupts(phydev);
 619
 620         if (err)
 621                 phy_error(phydev);
 622
 623         free_irq(phydev->irq, phydev);
 624
 625         /*
 626          * Cannot call flush_scheduled_work() here as desired because
 627          * of rtnl_lock(), but we do not really care about what would
 628          * be done, except from enable_irq(), so cancel any work
 629          * possibly pending and take care of the matter below.
 630          */
 631         cancel_work_sync(&phydev->phy_queue);
 632         /*
 633          * If work indeed has been cancelled, disable_irq() will have
 634          * been left unbalanced from phy_interrupt() and enable_irq()
 635          * has to be called so that other devices on the line work.
 636          */
 637         while (atomic_dec_return(&phydev->irq_disable) >= 0)
 638                 enable_irq(phydev->irq);
 639
 640         return err;
 641 }
 642 EXPORT_SYMBOL(phy_stop_interrupts);
 643
 644
 645 /**
 646  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
 647  * @work: work_struct that describes the work to be done
 648  */
 649 static void phy_change(struct work_struct *work)
 650 {
 651         int err;
 652         struct phy_device *phydev =
 653                 container_of(work, struct phy_device, phy_queue);
 654
 655         if (phydev->drv->did_interrupt &&
 656             !phydev->drv->did_interrupt(phydev))
 657                 goto ignore;
 658
 659         err = phy_disable_interrupts(phydev);
 660
 661         if (err)
 662                 goto phy_err;
 663
 664         mutex_lock(&phydev->lock);
 665         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 666                 phydev->state = PHY_CHANGELINK;
 667         mutex_unlock(&phydev->lock);
 668
 669         atomic_dec(&phydev->irq_disable);
 670         enable_irq(phydev->irq);
 671
 672         /* Reenable interrupts */
 673         if (PHY_HALTED != phydev->state)
 674                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 675
 676         if (err)
 677                 goto irq_enable_err;
 678
 679         /* reschedule state queue work to run as soon as possible */
 680         cancel_delayed_work_sync(&phydev->state_queue);
 681         schedule_delayed_work(&phydev->state_queue, 0);
 682
 683         return;
 684
 685 ignore:
 686         atomic_dec(&phydev->irq_disable);
 687         enable_irq(phydev->irq);
 688         return;
 689
 690 irq_enable_err:
 691         disable_irq(phydev->irq);
 692         atomic_inc(&phydev->irq_disable);
 693 phy_err:
 694         phy_error(phydev);
 695 }
 696
 697 /**
 698  * phy_stop - Bring down the PHY link, and stop checking the status
 699  * @phydev: target phy_device struct
 700  */
 701 void phy_stop(struct phy_device *phydev)
 702 {
 703         mutex_lock(&phydev->lock);
 704
 705         if (PHY_HALTED == phydev->state)
 706                 goto out_unlock;
 707
 708         if (phydev->irq != PHY_POLL) {
 709                 /* Disable PHY Interrupts */
 710                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 711
 712                 /* Clear any pending interrupts */
 713                 phy_clear_interrupt(phydev);
 714         }
 715
 716         phydev->state = PHY_HALTED;
 717
 718 out_unlock:
 719         mutex_unlock(&phydev->lock);
 720
 721         /*
 722          * Cannot call flush_scheduled_work() here as desired because
 723          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
 724          * will not reenable interrupts.
 725          */
 726 }
 727
 728
 729 /**
 730  * phy_start - start or restart a PHY device
 731  * @phydev: target phy_device struct
 732  *
 733  * Description: Indicates the attached device's readiness to
 734  *   handle PHY-related work.  Used during startup to start the
 735  *   PHY, and after a call to phy_stop() to resume operation.
 736  *   Also used to indicate the MDIO bus has cleared an error
 737  *   condition.
 738  */
 739 void phy_start(struct phy_device *phydev)
 740 {
 741         mutex_lock(&phydev->lock);
 742
 743         switch (phydev->state) {
 744                 case PHY_STARTING:
 745                         phydev->state = PHY_PENDING;
 746                         break;
 747                 case PHY_READY:
 748                         phydev->state = PHY_UP;
 749                         break;
 750                 case PHY_HALTED:
 751                         phydev->state = PHY_RESUMING;
 752                 default:
 753                         break;
 754         }
 755         mutex_unlock(&phydev->lock);
 756 }
 757 EXPORT_SYMBOL(phy_stop);
 758 EXPORT_SYMBOL(phy_start);
 759
 760 /**
 761  * phy_state_machine - Handle the state machine
 762  * @work: work_struct that describes the work to be done
 763  */
 764 void phy_state_machine(struct work_struct *work)
 765 {
 766         struct delayed_work *dwork = to_delayed_work(work);
 767         struct phy_device *phydev =
 768                         container_of(dwork, struct phy_device, state_queue);
 769         int needs_aneg = 0;
 770         int err = 0;
 771
 772         mutex_lock(&phydev->lock);
 773
 774         if (phydev->adjust_state)
 775                 phydev->adjust_state(phydev->attached_dev);
 776
 777         switch(phydev->state) {
 778                 case PHY_DOWN:
 779                 case PHY_STARTING:
 780                 case PHY_READY:
 781                 case PHY_PENDING:
 782                         break;
 783                 case PHY_UP:
 784                         needs_aneg = 1;
 785
 786                         phydev->link_timeout = PHY_AN_TIMEOUT;
 787
 788                         break;
 789                 case PHY_AN:
 790                         err = phy_read_status(phydev);
 791
 792                         if (err < 0)
 793                                 break;
 794
 795                         /* If the link is down, give up on
 796                          * negotiation for now */
 797                         if (!phydev->link) {
 798                                 phydev->state = PHY_NOLINK;
 799                                 netif_carrier_off(phydev->attached_dev);
 800                                 phydev->adjust_link(phydev->attached_dev);
 801                                 break;
 802                         }
 803
 804                         /* Check if negotiation is done.  Break
 805                          * if there's an error */
 806                         err = phy_aneg_done(phydev);
 807                         if (err < 0)
 808                                 break;
 809
 810                         /* If AN is done, we're running */
 811                         if (err > 0) {
 812                                 phydev->state = PHY_RUNNING;
 813                                 netif_carrier_on(phydev->attached_dev);
 814                                 phydev->adjust_link(phydev->attached_dev);
 815
 816                         } else if (0 == phydev->link_timeout--) {
 817                                 int idx;
 818
 819                                 needs_aneg = 1;
 820                                 /* If we have the magic_aneg bit,
 821                                  * we try again */
 822                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
 823                                         break;
 824
 825                                 /* The timer expired, and we still
 826                                  * don't have a setting, so we try
 827                                  * forcing it until we find one that
 828                                  * works, starting from the fastest speed,
 829                                  * and working our way down */
 830                                 idx = phy_find_valid(0, phydev->supported);
 831
 832                                 phydev->speed = settings[idx].speed;
 833                                 phydev->duplex = settings[idx].duplex;
 834
 835                                 phydev->autoneg = AUTONEG_DISABLE;
 836
 837                                 pr_info("Trying %d/%s\n", phydev->speed,
 838                                                 DUPLEX_FULL ==
 839                                                 phydev->duplex ?
 840                                                 "FULL" : "HALF");
 841                         }
 842                         break;
 843                 case PHY_NOLINK:
 844                         err = phy_read_status(phydev);
 845
 846                         if (err)
 847                                 break;
 848
 849                         if (phydev->link) {
 850                                 phydev->state = PHY_RUNNING;
 851                                 netif_carrier_on(phydev->attached_dev);
 852                                 phydev->adjust_link(phydev->attached_dev);
 853                         }
 854                         break;
 855                 case PHY_FORCING:
 856                         err = genphy_update_link(phydev);
 857
 858                         if (err)
 859                                 break;
 860
 861                         if (phydev->link) {
 862                                 phydev->state = PHY_RUNNING;
 863                                 netif_carrier_on(phydev->attached_dev);
 864                         } else {
 865                                 if (0 == phydev->link_timeout--) {
 866                                         phy_force_reduction(phydev);
 867                                         needs_aneg = 1;
 868                                 }
 869                         }
 870
 871                         phydev->adjust_link(phydev->attached_dev);
 872                         break;
 873                 case PHY_RUNNING:
 874                         /* Only register a CHANGE if we are
 875                          * polling */
 876                         if (PHY_POLL == phydev->irq)
 877                                 phydev->state = PHY_CHANGELINK;
 878                         break;
 879                 case PHY_CHANGELINK:
 880                         err = phy_read_status(phydev);
 881
 882                         if (err)
 883                                 break;
 884
 885                         if (phydev->link) {
 886                                 phydev->state = PHY_RUNNING;
 887                                 netif_carrier_on(phydev->attached_dev);
 888                         } else {
 889                                 phydev->state = PHY_NOLINK;
 890                                 netif_carrier_off(phydev->attached_dev);
 891                         }
 892
 893                         phydev->adjust_link(phydev->attached_dev);
 894
 895                         if (PHY_POLL != phydev->irq)
 896                                 err = phy_config_interrupt(phydev,
 897                                                 PHY_INTERRUPT_ENABLED);
 898                         break;
 899                 case PHY_HALTED:
 900                         if (phydev->link) {
 901                                 phydev->link = 0;
 902                                 netif_carrier_off(phydev->attached_dev);
 903                                 phydev->adjust_link(phydev->attached_dev);
 904                         }
 905                         break;
 906                 case PHY_RESUMING:
 907
 908                         err = phy_clear_interrupt(phydev);
 909
 910                         if (err)
 911                                 break;
 912
 913                         err = phy_config_interrupt(phydev,
 914                                         PHY_INTERRUPT_ENABLED);
 915
 916                         if (err)
 917                                 break;
 918
 919                         if (AUTONEG_ENABLE == phydev->autoneg) {
 920                                 err = phy_aneg_done(phydev);
 921                                 if (err < 0)
 922                                         break;
 923
 924                                 /* err > 0 if AN is done.
 925                                  * Otherwise, it's 0, and we're
 926                                  * still waiting for AN */
 927                                 if (err > 0) {
 928                                         err = phy_read_status(phydev);
 929                                         if (err)
 930                                                 break;
 931
 932                                         if (phydev->link) {
 933                                                 phydev->state = PHY_RUNNING;
 934                                                 netif_carrier_on(phydev->attached_dev);
 935                                         } else
 936                                                 phydev->state = PHY_NOLINK;
 937                                         phydev->adjust_link(phydev->attached_dev);
 938                                 } else {
 939                                         phydev->state = PHY_AN;
 940                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 941                                 }
 942                         } else {
 943                                 err = phy_read_status(phydev);
 944                                 if (err)
 945                                         break;
 946
 947                                 if (phydev->link) {
 948                                         phydev->state = PHY_RUNNING;
 949                                         netif_carrier_on(phydev->attached_dev);
 950                                 } else
 951                                         phydev->state = PHY_NOLINK;
 952                                 phydev->adjust_link(phydev->attached_dev);
 953                         }
 954                         break;
 955         }
 956
 957         mutex_unlock(&phydev->lock);
 958
 959         if (needs_aneg)
 960                 err = phy_start_aneg(phydev);
 961
 962         if (err < 0)
 963                 phy_error(phydev);
 964
 965         schedule_delayed_work(&phydev->state_queue, PHY_STATE_TIME * HZ);
 966 }