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 static void phy_timer(unsigned long data);
 418
 419 /**
 420  * phy_start_machine - start PHY state machine tracking
 421  * @phydev: the phy_device struct
 422  * @handler: callback function for state change notifications
 423  *
 424  * Description: The PHY infrastructure can run a state machine
 425  *   which tracks whether the PHY is starting up, negotiating,
 426  *   etc.  This function starts the timer which tracks the state
 427  *   of the PHY.  If you want to be notified when the state changes,
 428  *   pass in the callback @handler, otherwise, pass NULL.  If you
 429  *   want to maintain your own state machine, do not call this
 430  *   function.
 431  */
 432 void phy_start_machine(struct phy_device *phydev,
 433                 void (*handler)(struct net_device *))
 434 {
 435         phydev->adjust_state = handler;
 436
 437         INIT_WORK(&phydev->state_queue, phy_state_machine);
 438         init_timer(&phydev->phy_timer);
 439         phydev->phy_timer.function = &phy_timer;
 440         phydev->phy_timer.data = (unsigned long) phydev;
 441         mod_timer(&phydev->phy_timer, jiffies + HZ);
 442 }
 443
 444 /**
 445  * phy_stop_machine - stop the PHY state machine tracking
 446  * @phydev: target phy_device struct
 447  *
 448  * Description: Stops the state machine timer, sets the state to UP
 449  *   (unless it wasn't up yet). This function must be called BEFORE
 450  *   phy_detach.
 451  */
 452 void phy_stop_machine(struct phy_device *phydev)
 453 {
 454         del_timer_sync(&phydev->phy_timer);
 455         cancel_work_sync(&phydev->state_queue);
 456
 457         mutex_lock(&phydev->lock);
 458         if (phydev->state > PHY_UP)
 459                 phydev->state = PHY_UP;
 460         mutex_unlock(&phydev->lock);
 461
 462         phydev->adjust_state = NULL;
 463 }
 464
 465 /**
 466  * phy_force_reduction - reduce PHY speed/duplex settings by one step
 467  * @phydev: target phy_device struct
 468  *
 469  * Description: Reduces the speed/duplex settings by one notch,
 470  *   in this order--
 471  *   1000/FULL, 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF.
 472  *   The function bottoms out at 10/HALF.
 473  */
 474 static void phy_force_reduction(struct phy_device *phydev)
 475 {
 476         int idx;
 477
 478         idx = phy_find_setting(phydev->speed, phydev->duplex);
 479
 480         idx++;
 481
 482         idx = phy_find_valid(idx, phydev->supported);
 483
 484         phydev->speed = settings[idx].speed;
 485         phydev->duplex = settings[idx].duplex;
 486
 487         pr_info("Trying %d/%s\n", phydev->speed,
 488                         DUPLEX_FULL == phydev->duplex ?
 489                         "FULL" : "HALF");
 490 }
 491
 492
 493 /**
 494  * phy_error - enter HALTED state for this PHY device
 495  * @phydev: target phy_device struct
 496  *
 497  * Moves the PHY to the HALTED state in response to a read
 498  * or write error, and tells the controller the link is down.
 499  * Must not be called from interrupt context, or while the
 500  * phydev->lock is held.
 501  */
 502 static void phy_error(struct phy_device *phydev)
 503 {
 504         mutex_lock(&phydev->lock);
 505         phydev->state = PHY_HALTED;
 506         mutex_unlock(&phydev->lock);
 507 }
 508
 509 /**
 510  * phy_interrupt - PHY interrupt handler
 511  * @irq: interrupt line
 512  * @phy_dat: phy_device pointer
 513  *
 514  * Description: When a PHY interrupt occurs, the handler disables
 515  * interrupts, and schedules a work task to clear the interrupt.
 516  */
 517 static irqreturn_t phy_interrupt(int irq, void *phy_dat)
 518 {
 519         struct phy_device *phydev = phy_dat;
 520
 521         if (PHY_HALTED == phydev->state)
 522                 return IRQ_NONE;                /* It can't be ours.  */
 523
 524         /* The MDIO bus is not allowed to be written in interrupt
 525          * context, so we need to disable the irq here.  A work
 526          * queue will write the PHY to disable and clear the
 527          * interrupt, and then reenable the irq line. */
 528         disable_irq_nosync(irq);
 529         atomic_inc(&phydev->irq_disable);
 530
 531         schedule_work(&phydev->phy_queue);
 532
 533         return IRQ_HANDLED;
 534 }
 535
 536 /**
 537  * phy_enable_interrupts - Enable the interrupts from the PHY side
 538  * @phydev: target phy_device struct
 539  */
 540 int phy_enable_interrupts(struct phy_device *phydev)
 541 {
 542         int err;
 543
 544         err = phy_clear_interrupt(phydev);
 545
 546         if (err < 0)
 547                 return err;
 548
 549         err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 550
 551         return err;
 552 }
 553 EXPORT_SYMBOL(phy_enable_interrupts);
 554
 555 /**
 556  * phy_disable_interrupts - Disable the PHY interrupts from the PHY side
 557  * @phydev: target phy_device struct
 558  */
 559 int phy_disable_interrupts(struct phy_device *phydev)
 560 {
 561         int err;
 562
 563         /* Disable PHY interrupts */
 564         err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 565
 566         if (err)
 567                 goto phy_err;
 568
 569         /* Clear the interrupt */
 570         err = phy_clear_interrupt(phydev);
 571
 572         if (err)
 573                 goto phy_err;
 574
 575         return 0;
 576
 577 phy_err:
 578         phy_error(phydev);
 579
 580         return err;
 581 }
 582 EXPORT_SYMBOL(phy_disable_interrupts);
 583
 584 /**
 585  * phy_start_interrupts - request and enable interrupts for a PHY device
 586  * @phydev: target phy_device struct
 587  *
 588  * Description: Request the interrupt for the given PHY.
 589  *   If this fails, then we set irq to PHY_POLL.
 590  *   Otherwise, we enable the interrupts in the PHY.
 591  *   This should only be called with a valid IRQ number.
 592  *   Returns 0 on success or < 0 on error.
 593  */
 594 int phy_start_interrupts(struct phy_device *phydev)
 595 {
 596         int err = 0;
 597
 598         INIT_WORK(&phydev->phy_queue, phy_change);
 599
 600         atomic_set(&phydev->irq_disable, 0);
 601         if (request_irq(phydev->irq, phy_interrupt,
 602                                 IRQF_SHARED,
 603                                 "phy_interrupt",
 604                                 phydev) < 0) {
 605                 printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n",
 606                                 phydev->bus->name,
 607                                 phydev->irq);
 608                 phydev->irq = PHY_POLL;
 609                 return 0;
 610         }
 611
 612         err = phy_enable_interrupts(phydev);
 613
 614         return err;
 615 }
 616 EXPORT_SYMBOL(phy_start_interrupts);
 617
 618 /**
 619  * phy_stop_interrupts - disable interrupts from a PHY device
 620  * @phydev: target phy_device struct
 621  */
 622 int phy_stop_interrupts(struct phy_device *phydev)
 623 {
 624         int err;
 625
 626         err = phy_disable_interrupts(phydev);
 627
 628         if (err)
 629                 phy_error(phydev);
 630
 631         free_irq(phydev->irq, phydev);
 632
 633         /*
 634          * Cannot call flush_scheduled_work() here as desired because
 635          * of rtnl_lock(), but we do not really care about what would
 636          * be done, except from enable_irq(), so cancel any work
 637          * possibly pending and take care of the matter below.
 638          */
 639         cancel_work_sync(&phydev->phy_queue);
 640         /*
 641          * If work indeed has been cancelled, disable_irq() will have
 642          * been left unbalanced from phy_interrupt() and enable_irq()
 643          * has to be called so that other devices on the line work.
 644          */
 645         while (atomic_dec_return(&phydev->irq_disable) >= 0)
 646                 enable_irq(phydev->irq);
 647
 648         return err;
 649 }
 650 EXPORT_SYMBOL(phy_stop_interrupts);
 651
 652
 653 /**
 654  * phy_change - Scheduled by the phy_interrupt/timer to handle PHY changes
 655  * @work: work_struct that describes the work to be done
 656  */
 657 static void phy_change(struct work_struct *work)
 658 {
 659         int err;
 660         struct phy_device *phydev =
 661                 container_of(work, struct phy_device, phy_queue);
 662
 663         err = phy_disable_interrupts(phydev);
 664
 665         if (err)
 666                 goto phy_err;
 667
 668         mutex_lock(&phydev->lock);
 669         if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state))
 670                 phydev->state = PHY_CHANGELINK;
 671         mutex_unlock(&phydev->lock);
 672
 673         atomic_dec(&phydev->irq_disable);
 674         enable_irq(phydev->irq);
 675
 676         /* Reenable interrupts */
 677         if (PHY_HALTED != phydev->state)
 678                 err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED);
 679
 680         if (err)
 681                 goto irq_enable_err;
 682
 683         /* Stop timer and run the state queue now.  The work function for
 684          * state_queue will start the timer up again.
 685          */
 686         del_timer(&phydev->phy_timer);
 687         schedule_work(&phydev->state_queue);
 688
 689         return;
 690
 691 irq_enable_err:
 692         disable_irq(phydev->irq);
 693         atomic_inc(&phydev->irq_disable);
 694 phy_err:
 695         phy_error(phydev);
 696 }
 697
 698 /**
 699  * phy_stop - Bring down the PHY link, and stop checking the status
 700  * @phydev: target phy_device struct
 701  */
 702 void phy_stop(struct phy_device *phydev)
 703 {
 704         mutex_lock(&phydev->lock);
 705
 706         if (PHY_HALTED == phydev->state)
 707                 goto out_unlock;
 708
 709         if (phydev->irq != PHY_POLL) {
 710                 /* Disable PHY Interrupts */
 711                 phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED);
 712
 713                 /* Clear any pending interrupts */
 714                 phy_clear_interrupt(phydev);
 715         }
 716
 717         phydev->state = PHY_HALTED;
 718
 719 out_unlock:
 720         mutex_unlock(&phydev->lock);
 721
 722         /*
 723          * Cannot call flush_scheduled_work() here as desired because
 724          * of rtnl_lock(), but PHY_HALTED shall guarantee phy_change()
 725          * will not reenable interrupts.
 726          */
 727 }
 728
 729
 730 /**
 731  * phy_start - start or restart a PHY device
 732  * @phydev: target phy_device struct
 733  *
 734  * Description: Indicates the attached device's readiness to
 735  *   handle PHY-related work.  Used during startup to start the
 736  *   PHY, and after a call to phy_stop() to resume operation.
 737  *   Also used to indicate the MDIO bus has cleared an error
 738  *   condition.
 739  */
 740 void phy_start(struct phy_device *phydev)
 741 {
 742         mutex_lock(&phydev->lock);
 743
 744         switch (phydev->state) {
 745                 case PHY_STARTING:
 746                         phydev->state = PHY_PENDING;
 747                         break;
 748                 case PHY_READY:
 749                         phydev->state = PHY_UP;
 750                         break;
 751                 case PHY_HALTED:
 752                         phydev->state = PHY_RESUMING;
 753                 default:
 754                         break;
 755         }
 756         mutex_unlock(&phydev->lock);
 757 }
 758 EXPORT_SYMBOL(phy_stop);
 759 EXPORT_SYMBOL(phy_start);
 760
 761 /**
 762  * phy_state_machine - Handle the state machine
 763  * @work: work_struct that describes the work to be done
 764  *
 765  * Description: Scheduled by the state_queue workqueue each time
 766  *   phy_timer is triggered.
 767  */
 768 static void phy_state_machine(struct work_struct *work)
 769 {
 770         struct phy_device *phydev =
 771                         container_of(work, struct phy_device, state_queue);
 772         int needs_aneg = 0;
 773         int err = 0;
 774
 775         mutex_lock(&phydev->lock);
 776
 777         if (phydev->adjust_state)
 778                 phydev->adjust_state(phydev->attached_dev);
 779
 780         switch(phydev->state) {
 781                 case PHY_DOWN:
 782                 case PHY_STARTING:
 783                 case PHY_READY:
 784                 case PHY_PENDING:
 785                         break;
 786                 case PHY_UP:
 787                         needs_aneg = 1;
 788
 789                         phydev->link_timeout = PHY_AN_TIMEOUT;
 790
 791                         break;
 792                 case PHY_AN:
 793                         err = phy_read_status(phydev);
 794
 795                         if (err < 0)
 796                                 break;
 797
 798                         /* If the link is down, give up on
 799                          * negotiation for now */
 800                         if (!phydev->link) {
 801                                 phydev->state = PHY_NOLINK;
 802                                 netif_carrier_off(phydev->attached_dev);
 803                                 phydev->adjust_link(phydev->attached_dev);
 804                                 break;
 805                         }
 806
 807                         /* Check if negotiation is done.  Break
 808                          * if there's an error */
 809                         err = phy_aneg_done(phydev);
 810                         if (err < 0)
 811                                 break;
 812
 813                         /* If AN is done, we're running */
 814                         if (err > 0) {
 815                                 phydev->state = PHY_RUNNING;
 816                                 netif_carrier_on(phydev->attached_dev);
 817                                 phydev->adjust_link(phydev->attached_dev);
 818
 819                         } else if (0 == phydev->link_timeout--) {
 820                                 int idx;
 821
 822                                 needs_aneg = 1;
 823                                 /* If we have the magic_aneg bit,
 824                                  * we try again */
 825                                 if (phydev->drv->flags & PHY_HAS_MAGICANEG)
 826                                         break;
 827
 828                                 /* The timer expired, and we still
 829                                  * don't have a setting, so we try
 830                                  * forcing it until we find one that
 831                                  * works, starting from the fastest speed,
 832                                  * and working our way down */
 833                                 idx = phy_find_valid(0, phydev->supported);
 834
 835                                 phydev->speed = settings[idx].speed;
 836                                 phydev->duplex = settings[idx].duplex;
 837
 838                                 phydev->autoneg = AUTONEG_DISABLE;
 839
 840                                 pr_info("Trying %d/%s\n", phydev->speed,
 841                                                 DUPLEX_FULL ==
 842                                                 phydev->duplex ?
 843                                                 "FULL" : "HALF");
 844                         }
 845                         break;
 846                 case PHY_NOLINK:
 847                         err = phy_read_status(phydev);
 848
 849                         if (err)
 850                                 break;
 851
 852                         if (phydev->link) {
 853                                 phydev->state = PHY_RUNNING;
 854                                 netif_carrier_on(phydev->attached_dev);
 855                                 phydev->adjust_link(phydev->attached_dev);
 856                         }
 857                         break;
 858                 case PHY_FORCING:
 859                         err = genphy_update_link(phydev);
 860
 861                         if (err)
 862                                 break;
 863
 864                         if (phydev->link) {
 865                                 phydev->state = PHY_RUNNING;
 866                                 netif_carrier_on(phydev->attached_dev);
 867                         } else {
 868                                 if (0 == phydev->link_timeout--) {
 869                                         phy_force_reduction(phydev);
 870                                         needs_aneg = 1;
 871                                 }
 872                         }
 873
 874                         phydev->adjust_link(phydev->attached_dev);
 875                         break;
 876                 case PHY_RUNNING:
 877                         /* Only register a CHANGE if we are
 878                          * polling */
 879                         if (PHY_POLL == phydev->irq)
 880                                 phydev->state = PHY_CHANGELINK;
 881                         break;
 882                 case PHY_CHANGELINK:
 883                         err = phy_read_status(phydev);
 884
 885                         if (err)
 886                                 break;
 887
 888                         if (phydev->link) {
 889                                 phydev->state = PHY_RUNNING;
 890                                 netif_carrier_on(phydev->attached_dev);
 891                         } else {
 892                                 phydev->state = PHY_NOLINK;
 893                                 netif_carrier_off(phydev->attached_dev);
 894                         }
 895
 896                         phydev->adjust_link(phydev->attached_dev);
 897
 898                         if (PHY_POLL != phydev->irq)
 899                                 err = phy_config_interrupt(phydev,
 900                                                 PHY_INTERRUPT_ENABLED);
 901                         break;
 902                 case PHY_HALTED:
 903                         if (phydev->link) {
 904                                 phydev->link = 0;
 905                                 netif_carrier_off(phydev->attached_dev);
 906                                 phydev->adjust_link(phydev->attached_dev);
 907                         }
 908                         break;
 909                 case PHY_RESUMING:
 910
 911                         err = phy_clear_interrupt(phydev);
 912
 913                         if (err)
 914                                 break;
 915
 916                         err = phy_config_interrupt(phydev,
 917                                         PHY_INTERRUPT_ENABLED);
 918
 919                         if (err)
 920                                 break;
 921
 922                         if (AUTONEG_ENABLE == phydev->autoneg) {
 923                                 err = phy_aneg_done(phydev);
 924                                 if (err < 0)
 925                                         break;
 926
 927                                 /* err > 0 if AN is done.
 928                                  * Otherwise, it's 0, and we're
 929                                  * still waiting for AN */
 930                                 if (err > 0) {
 931                                         phydev->state = PHY_RUNNING;
 932                                 } else {
 933                                         phydev->state = PHY_AN;
 934                                         phydev->link_timeout = PHY_AN_TIMEOUT;
 935                                 }
 936                         } else
 937                                 phydev->state = PHY_RUNNING;
 938                         break;
 939         }
 940
 941         mutex_unlock(&phydev->lock);
 942
 943         if (needs_aneg)
 944                 err = phy_start_aneg(phydev);
 945
 946         if (err < 0)
 947                 phy_error(phydev);
 948
 949         mod_timer(&phydev->phy_timer, jiffies + PHY_STATE_TIME * HZ);
 950 }
 951
 952 /* PHY timer which schedules the state machine work */
 953 static void phy_timer(unsigned long data)
 954 {
 955         struct phy_device *phydev = (struct phy_device *)data;
 956
 957         /*
 958          * PHY I/O operations can potentially sleep so we ensure that
 959          * it's done from a process context
 960          */
 961         schedule_work(&phydev->state_queue);
 962 }