drivers/pci/hotplug/shpchp_ctrl.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Standard Hot Plug Controller Driver
   4  *
   5  * Copyright (C) 1995,2001 Compaq Computer Corporation
   6  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   7  * Copyright (C) 2001 IBM Corp.
   8  * Copyright (C) 2003-2004 Intel Corporation
   9  *
  10  * All rights reserved.
  11  *
  12  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
  13  *
  14  */
  15
  16 #include <linux/module.h>
  17 #include <linux/kernel.h>
  18 #include <linux/types.h>
  19 #include <linux/slab.h>
  20 #include <linux/pci.h>
  21 #include "../pci.h"
  22 #include "shpchp.h"
  23
  24 static void interrupt_event_handler(struct work_struct *work);
  25 static int shpchp_enable_slot(struct slot *p_slot);
  26 static int shpchp_disable_slot(struct slot *p_slot);
  27
  28 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
  29 {
  30         struct event_info *info;
  31
  32         info = kmalloc(sizeof(*info), GFP_ATOMIC);
  33         if (!info)
  34                 return -ENOMEM;
  35
  36         info->event_type = event_type;
  37         info->p_slot = p_slot;
  38         INIT_WORK(&info->work, interrupt_event_handler);
  39
  40         queue_work(p_slot->wq, &info->work);
  41
  42         return 0;
  43 }
  44
  45 u8 shpchp_handle_attention_button(u8 hp_slot, struct controller *ctrl)
  46 {
  47         struct slot *p_slot;
  48         u32 event_type;
  49
  50         /* Attention Button Change */
  51         ctrl_dbg(ctrl, "Attention button interrupt received\n");
  52
  53         p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
  54         p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
  55
  56         /*
  57          *  Button pressed - See if need to TAKE ACTION!!!
  58          */
  59         ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
  60         event_type = INT_BUTTON_PRESS;
  61
  62         queue_interrupt_event(p_slot, event_type);
  63
  64         return 0;
  65
  66 }
  67
  68 u8 shpchp_handle_switch_change(u8 hp_slot, struct controller *ctrl)
  69 {
  70         struct slot *p_slot;
  71         u8 getstatus;
  72         u32 event_type;
  73
  74         /* Switch Change */
  75         ctrl_dbg(ctrl, "Switch interrupt received\n");
  76
  77         p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
  78         p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
  79         p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
  80         ctrl_dbg(ctrl, "Card present %x Power status %x\n",
  81                  p_slot->presence_save, p_slot->pwr_save);
  82
  83         if (getstatus) {
  84                 /*
  85                  * Switch opened
  86                  */
  87                 ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
  88                 event_type = INT_SWITCH_OPEN;
  89                 if (p_slot->pwr_save && p_slot->presence_save) {
  90                         event_type = INT_POWER_FAULT;
  91                         ctrl_err(ctrl, "Surprise Removal of card\n");
  92                 }
  93         } else {
  94                 /*
  95                  *  Switch closed
  96                  */
  97                 ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
  98                 event_type = INT_SWITCH_CLOSE;
  99         }
 100
 101         queue_interrupt_event(p_slot, event_type);
 102
 103         return 1;
 104 }
 105
 106 u8 shpchp_handle_presence_change(u8 hp_slot, struct controller *ctrl)
 107 {
 108         struct slot *p_slot;
 109         u32 event_type;
 110
 111         /* Presence Change */
 112         ctrl_dbg(ctrl, "Presence/Notify input change\n");
 113
 114         p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 115
 116         /*
 117          * Save the presence state
 118          */
 119         p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
 120         if (p_slot->presence_save) {
 121                 /*
 122                  * Card Present
 123                  */
 124                 ctrl_info(ctrl, "Card present on Slot(%s)\n",
 125                           slot_name(p_slot));
 126                 event_type = INT_PRESENCE_ON;
 127         } else {
 128                 /*
 129                  * Not Present
 130                  */
 131                 ctrl_info(ctrl, "Card not present on Slot(%s)\n",
 132                           slot_name(p_slot));
 133                 event_type = INT_PRESENCE_OFF;
 134         }
 135
 136         queue_interrupt_event(p_slot, event_type);
 137
 138         return 1;
 139 }
 140
 141 u8 shpchp_handle_power_fault(u8 hp_slot, struct controller *ctrl)
 142 {
 143         struct slot *p_slot;
 144         u32 event_type;
 145
 146         /* Power fault */
 147         ctrl_dbg(ctrl, "Power fault interrupt received\n");
 148
 149         p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 150
 151         if (!(p_slot->hpc_ops->query_power_fault(p_slot))) {
 152                 /*
 153                  * Power fault Cleared
 154                  */
 155                 ctrl_info(ctrl, "Power fault cleared on Slot(%s)\n",
 156                           slot_name(p_slot));
 157                 p_slot->status = 0x00;
 158                 event_type = INT_POWER_FAULT_CLEAR;
 159         } else {
 160                 /*
 161                  *   Power fault
 162                  */
 163                 ctrl_info(ctrl, "Power fault on Slot(%s)\n", slot_name(p_slot));
 164                 event_type = INT_POWER_FAULT;
 165                 /* set power fault status for this board */
 166                 p_slot->status = 0xFF;
 167                 ctrl_info(ctrl, "Power fault bit %x set\n", hp_slot);
 168         }
 169
 170         queue_interrupt_event(p_slot, event_type);
 171
 172         return 1;
 173 }
 174
 175 /* The following routines constitute the bulk of the
 176    hotplug controller logic
 177  */
 178 static int change_bus_speed(struct controller *ctrl, struct slot *p_slot,
 179                 enum pci_bus_speed speed)
 180 {
 181         int rc = 0;
 182
 183         ctrl_dbg(ctrl, "Change speed to %d\n", speed);
 184         rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, speed);
 185         if (rc) {
 186                 ctrl_err(ctrl, "%s: Issue of set bus speed mode command failed\n",
 187                          __func__);
 188                 return WRONG_BUS_FREQUENCY;
 189         }
 190         return rc;
 191 }
 192
 193 static int fix_bus_speed(struct controller *ctrl, struct slot *pslot,
 194                 u8 flag, enum pci_bus_speed asp, enum pci_bus_speed bsp,
 195                 enum pci_bus_speed msp)
 196 {
 197         int rc = 0;
 198
 199         /*
 200          * If other slots on the same bus are occupied, we cannot
 201          * change the bus speed.
 202          */
 203         if (flag) {
 204                 if (asp < bsp) {
 205                         ctrl_err(ctrl, "Speed of bus %x and adapter %x mismatch\n",
 206                                  bsp, asp);
 207                         rc = WRONG_BUS_FREQUENCY;
 208                 }
 209                 return rc;
 210         }
 211
 212         if (asp < msp) {
 213                 if (bsp != asp)
 214                         rc = change_bus_speed(ctrl, pslot, asp);
 215         } else {
 216                 if (bsp != msp)
 217                         rc = change_bus_speed(ctrl, pslot, msp);
 218         }
 219         return rc;
 220 }
 221
 222 /**
 223  * board_added - Called after a board has been added to the system.
 224  * @p_slot: target &slot
 225  *
 226  * Turns power on for the board.
 227  * Configures board.
 228  */
 229 static int board_added(struct slot *p_slot)
 230 {
 231         u8 hp_slot;
 232         u8 slots_not_empty = 0;
 233         int rc = 0;
 234         enum pci_bus_speed asp, bsp, msp;
 235         struct controller *ctrl = p_slot->ctrl;
 236         struct pci_bus *parent = ctrl->pci_dev->subordinate;
 237
 238         hp_slot = p_slot->device - ctrl->slot_device_offset;
 239
 240         ctrl_dbg(ctrl, "%s: p_slot->device, slot_offset, hp_slot = %d, %d ,%d\n",
 241                  __func__, p_slot->device, ctrl->slot_device_offset, hp_slot);
 242
 243         /* Power on slot without connecting to bus */
 244         rc = p_slot->hpc_ops->power_on_slot(p_slot);
 245         if (rc) {
 246                 ctrl_err(ctrl, "Failed to power on slot\n");
 247                 return -1;
 248         }
 249
 250         if ((ctrl->pci_dev->vendor == 0x8086) && (ctrl->pci_dev->device == 0x0332)) {
 251                 rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, PCI_SPEED_33MHz);
 252                 if (rc) {
 253                         ctrl_err(ctrl, "%s: Issue of set bus speed mode command failed\n",
 254                                  __func__);
 255                         return WRONG_BUS_FREQUENCY;
 256                 }
 257
 258                 /* turn on board, blink green LED, turn off Amber LED */
 259                 rc = p_slot->hpc_ops->slot_enable(p_slot);
 260                 if (rc) {
 261                         ctrl_err(ctrl, "Issue of Slot Enable command failed\n");
 262                         return rc;
 263                 }
 264         }
 265
 266         rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &asp);
 267         if (rc) {
 268                 ctrl_err(ctrl, "Can't get adapter speed or bus mode mismatch\n");
 269                 return WRONG_BUS_FREQUENCY;
 270         }
 271
 272         bsp = ctrl->pci_dev->subordinate->cur_bus_speed;
 273         msp = ctrl->pci_dev->subordinate->max_bus_speed;
 274
 275         /* Check if there are other slots or devices on the same bus */
 276         if (!list_empty(&ctrl->pci_dev->subordinate->devices))
 277                 slots_not_empty = 1;
 278
 279         ctrl_dbg(ctrl, "%s: slots_not_empty %d, adapter_speed %d, bus_speed %d, max_bus_speed %d\n",
 280                  __func__, slots_not_empty, asp,
 281                  bsp, msp);
 282
 283         rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, asp, bsp, msp);
 284         if (rc)
 285                 return rc;
 286
 287         /* turn on board, blink green LED, turn off Amber LED */
 288         rc = p_slot->hpc_ops->slot_enable(p_slot);
 289         if (rc) {
 290                 ctrl_err(ctrl, "Issue of Slot Enable command failed\n");
 291                 return rc;
 292         }
 293
 294         /* Wait for ~1 second */
 295         msleep(1000);
 296
 297         ctrl_dbg(ctrl, "%s: slot status = %x\n", __func__, p_slot->status);
 298         /* Check for a power fault */
 299         if (p_slot->status == 0xFF) {
 300                 /* power fault occurred, but it was benign */
 301                 ctrl_dbg(ctrl, "%s: Power fault\n", __func__);
 302                 rc = POWER_FAILURE;
 303                 p_slot->status = 0;
 304                 goto err_exit;
 305         }
 306
 307         if (shpchp_configure_device(p_slot)) {
 308                 ctrl_err(ctrl, "Cannot add device at %04x:%02x:%02x\n",
 309                          pci_domain_nr(parent), p_slot->bus, p_slot->device);
 310                 goto err_exit;
 311         }
 312
 313         p_slot->status = 0;
 314         p_slot->is_a_board = 0x01;
 315         p_slot->pwr_save = 1;
 316
 317         p_slot->hpc_ops->green_led_on(p_slot);
 318
 319         return 0;
 320
 321 err_exit:
 322         /* turn off slot, turn on Amber LED, turn off Green LED */
 323         rc = p_slot->hpc_ops->slot_disable(p_slot);
 324         if (rc) {
 325                 ctrl_err(ctrl, "%s: Issue of Slot Disable command failed\n",
 326                          __func__);
 327                 return rc;
 328         }
 329
 330         return(rc);
 331 }
 332
 333
 334 /**
 335  * remove_board - Turns off slot and LEDs
 336  * @p_slot: target &slot
 337  */
 338 static int remove_board(struct slot *p_slot)
 339 {
 340         struct controller *ctrl = p_slot->ctrl;
 341         u8 hp_slot;
 342         int rc;
 343
 344         shpchp_unconfigure_device(p_slot);
 345
 346         hp_slot = p_slot->device - ctrl->slot_device_offset;
 347         p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
 348
 349         ctrl_dbg(ctrl, "%s: hp_slot = %d\n", __func__, hp_slot);
 350
 351         /* Change status to shutdown */
 352         if (p_slot->is_a_board)
 353                 p_slot->status = 0x01;
 354
 355         /* turn off slot, turn on Amber LED, turn off Green LED */
 356         rc = p_slot->hpc_ops->slot_disable(p_slot);
 357         if (rc) {
 358                 ctrl_err(ctrl, "%s: Issue of Slot Disable command failed\n",
 359                          __func__);
 360                 return rc;
 361         }
 362
 363         rc = p_slot->hpc_ops->set_attention_status(p_slot, 0);
 364         if (rc) {
 365                 ctrl_err(ctrl, "Issue of Set Attention command failed\n");
 366                 return rc;
 367         }
 368
 369         p_slot->pwr_save = 0;
 370         p_slot->is_a_board = 0;
 371
 372         return 0;
 373 }
 374
 375
 376 struct pushbutton_work_info {
 377         struct slot *p_slot;
 378         struct work_struct work;
 379 };
 380
 381 /**
 382  * shpchp_pushbutton_thread - handle pushbutton events
 383  * @work: &struct work_struct to be handled
 384  *
 385  * Scheduled procedure to handle blocking stuff for the pushbuttons.
 386  * Handles all pending events and exits.
 387  */
 388 static void shpchp_pushbutton_thread(struct work_struct *work)
 389 {
 390         struct pushbutton_work_info *info =
 391                 container_of(work, struct pushbutton_work_info, work);
 392         struct slot *p_slot = info->p_slot;
 393
 394         mutex_lock(&p_slot->lock);
 395         switch (p_slot->state) {
 396         case POWEROFF_STATE:
 397                 mutex_unlock(&p_slot->lock);
 398                 shpchp_disable_slot(p_slot);
 399                 mutex_lock(&p_slot->lock);
 400                 p_slot->state = STATIC_STATE;
 401                 break;
 402         case POWERON_STATE:
 403                 mutex_unlock(&p_slot->lock);
 404                 if (shpchp_enable_slot(p_slot))
 405                         p_slot->hpc_ops->green_led_off(p_slot);
 406                 mutex_lock(&p_slot->lock);
 407                 p_slot->state = STATIC_STATE;
 408                 break;
 409         default:
 410                 break;
 411         }
 412         mutex_unlock(&p_slot->lock);
 413
 414         kfree(info);
 415 }
 416
 417 void shpchp_queue_pushbutton_work(struct work_struct *work)
 418 {
 419         struct slot *p_slot = container_of(work, struct slot, work.work);
 420         struct pushbutton_work_info *info;
 421
 422         info = kmalloc(sizeof(*info), GFP_KERNEL);
 423         if (!info) {
 424                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 425                          __func__);
 426                 return;
 427         }
 428         info->p_slot = p_slot;
 429         INIT_WORK(&info->work, shpchp_pushbutton_thread);
 430
 431         mutex_lock(&p_slot->lock);
 432         switch (p_slot->state) {
 433         case BLINKINGOFF_STATE:
 434                 p_slot->state = POWEROFF_STATE;
 435                 break;
 436         case BLINKINGON_STATE:
 437                 p_slot->state = POWERON_STATE;
 438                 break;
 439         default:
 440                 kfree(info);
 441                 goto out;
 442         }
 443         queue_work(p_slot->wq, &info->work);
 444  out:
 445         mutex_unlock(&p_slot->lock);
 446 }
 447
 448 static void update_slot_info(struct slot *slot)
 449 {
 450         slot->hpc_ops->get_power_status(slot, &slot->pwr_save);
 451         slot->hpc_ops->get_attention_status(slot, &slot->attention_save);
 452         slot->hpc_ops->get_latch_status(slot, &slot->latch_save);
 453         slot->hpc_ops->get_adapter_status(slot, &slot->presence_save);
 454 }
 455
 456 /*
 457  * Note: This function must be called with slot->lock held
 458  */
 459 static void handle_button_press_event(struct slot *p_slot)
 460 {
 461         u8 getstatus;
 462         struct controller *ctrl = p_slot->ctrl;
 463
 464         switch (p_slot->state) {
 465         case STATIC_STATE:
 466                 p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
 467                 if (getstatus) {
 468                         p_slot->state = BLINKINGOFF_STATE;
 469                         ctrl_info(ctrl, "PCI slot #%s - powering off due to button press\n",
 470                                   slot_name(p_slot));
 471                 } else {
 472                         p_slot->state = BLINKINGON_STATE;
 473                         ctrl_info(ctrl, "PCI slot #%s - powering on due to button press\n",
 474                                   slot_name(p_slot));
 475                 }
 476                 /* blink green LED and turn off amber */
 477                 p_slot->hpc_ops->green_led_blink(p_slot);
 478                 p_slot->hpc_ops->set_attention_status(p_slot, 0);
 479
 480                 queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
 481                 break;
 482         case BLINKINGOFF_STATE:
 483         case BLINKINGON_STATE:
 484                 /*
 485                  * Cancel if we are still blinking; this means that we
 486                  * press the attention again before the 5 sec. limit
 487                  * expires to cancel hot-add or hot-remove
 488                  */
 489                 ctrl_info(ctrl, "Button cancel on Slot(%s)\n",
 490                           slot_name(p_slot));
 491                 cancel_delayed_work(&p_slot->work);
 492                 if (p_slot->state == BLINKINGOFF_STATE)
 493                         p_slot->hpc_ops->green_led_on(p_slot);
 494                 else
 495                         p_slot->hpc_ops->green_led_off(p_slot);
 496                 p_slot->hpc_ops->set_attention_status(p_slot, 0);
 497                 ctrl_info(ctrl, "PCI slot #%s - action canceled due to button press\n",
 498                           slot_name(p_slot));
 499                 p_slot->state = STATIC_STATE;
 500                 break;
 501         case POWEROFF_STATE:
 502         case POWERON_STATE:
 503                 /*
 504                  * Ignore if the slot is on power-on or power-off state;
 505                  * this means that the previous attention button action
 506                  * to hot-add or hot-remove is undergoing
 507                  */
 508                 ctrl_info(ctrl, "Button ignore on Slot(%s)\n",
 509                           slot_name(p_slot));
 510                 update_slot_info(p_slot);
 511                 break;
 512         default:
 513                 ctrl_warn(ctrl, "Not a valid state\n");
 514                 break;
 515         }
 516 }
 517
 518 static void interrupt_event_handler(struct work_struct *work)
 519 {
 520         struct event_info *info = container_of(work, struct event_info, work);
 521         struct slot *p_slot = info->p_slot;
 522
 523         mutex_lock(&p_slot->lock);
 524         switch (info->event_type) {
 525         case INT_BUTTON_PRESS:
 526                 handle_button_press_event(p_slot);
 527                 break;
 528         case INT_POWER_FAULT:
 529                 ctrl_dbg(p_slot->ctrl, "%s: Power fault\n", __func__);
 530                 p_slot->hpc_ops->set_attention_status(p_slot, 1);
 531                 p_slot->hpc_ops->green_led_off(p_slot);
 532                 break;
 533         default:
 534                 update_slot_info(p_slot);
 535                 break;
 536         }
 537         mutex_unlock(&p_slot->lock);
 538
 539         kfree(info);
 540 }
 541
 542
 543 static int shpchp_enable_slot (struct slot *p_slot)
 544 {
 545         u8 getstatus = 0;
 546         int rc, retval = -ENODEV;
 547         struct controller *ctrl = p_slot->ctrl;
 548
 549         /* Check to see if (latch closed, card present, power off) */
 550         mutex_lock(&p_slot->ctrl->crit_sect);
 551         rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
 552         if (rc || !getstatus) {
 553                 ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
 554                 goto out;
 555         }
 556         rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
 557         if (rc || getstatus) {
 558                 ctrl_info(ctrl, "Latch open on slot(%s)\n", slot_name(p_slot));
 559                 goto out;
 560         }
 561         rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
 562         if (rc || getstatus) {
 563                 ctrl_info(ctrl, "Already enabled on slot(%s)\n",
 564                           slot_name(p_slot));
 565                 goto out;
 566         }
 567
 568         p_slot->is_a_board = 1;
 569
 570         /* We have to save the presence info for these slots */
 571         p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
 572         p_slot->hpc_ops->get_power_status(p_slot, &(p_slot->pwr_save));
 573         ctrl_dbg(ctrl, "%s: p_slot->pwr_save %x\n", __func__, p_slot->pwr_save);
 574         p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
 575
 576         if ((p_slot->ctrl->pci_dev->vendor == PCI_VENDOR_ID_AMD &&
 577              p_slot->ctrl->pci_dev->device == PCI_DEVICE_ID_AMD_POGO_7458)
 578              && p_slot->ctrl->num_slots == 1) {
 579                 /* handle AMD POGO errata; this must be done before enable  */
 580                 amd_pogo_errata_save_misc_reg(p_slot);
 581                 retval = board_added(p_slot);
 582                 /* handle AMD POGO errata; this must be done after enable  */
 583                 amd_pogo_errata_restore_misc_reg(p_slot);
 584         } else
 585                 retval = board_added(p_slot);
 586
 587         if (retval) {
 588                 p_slot->hpc_ops->get_adapter_status(p_slot,
 589                                 &(p_slot->presence_save));
 590                 p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
 591         }
 592
 593         update_slot_info(p_slot);
 594  out:
 595         mutex_unlock(&p_slot->ctrl->crit_sect);
 596         return retval;
 597 }
 598
 599
 600 static int shpchp_disable_slot (struct slot *p_slot)
 601 {
 602         u8 getstatus = 0;
 603         int rc, retval = -ENODEV;
 604         struct controller *ctrl = p_slot->ctrl;
 605
 606         if (!p_slot->ctrl)
 607                 return -ENODEV;
 608
 609         /* Check to see if (latch closed, card present, power on) */
 610         mutex_lock(&p_slot->ctrl->crit_sect);
 611
 612         rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
 613         if (rc || !getstatus) {
 614                 ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
 615                 goto out;
 616         }
 617         rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
 618         if (rc || getstatus) {
 619                 ctrl_info(ctrl, "Latch open on slot(%s)\n", slot_name(p_slot));
 620                 goto out;
 621         }
 622         rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
 623         if (rc || !getstatus) {
 624                 ctrl_info(ctrl, "Already disabled on slot(%s)\n",
 625                           slot_name(p_slot));
 626                 goto out;
 627         }
 628
 629         retval = remove_board(p_slot);
 630         update_slot_info(p_slot);
 631  out:
 632         mutex_unlock(&p_slot->ctrl->crit_sect);
 633         return retval;
 634 }
 635
 636 int shpchp_sysfs_enable_slot(struct slot *p_slot)
 637 {
 638         int retval = -ENODEV;
 639         struct controller *ctrl = p_slot->ctrl;
 640
 641         mutex_lock(&p_slot->lock);
 642         switch (p_slot->state) {
 643         case BLINKINGON_STATE:
 644                 cancel_delayed_work(&p_slot->work);
 645                 /* fall through */
 646         case STATIC_STATE:
 647                 p_slot->state = POWERON_STATE;
 648                 mutex_unlock(&p_slot->lock);
 649                 retval = shpchp_enable_slot(p_slot);
 650                 mutex_lock(&p_slot->lock);
 651                 p_slot->state = STATIC_STATE;
 652                 break;
 653         case POWERON_STATE:
 654                 ctrl_info(ctrl, "Slot %s is already in powering on state\n",
 655                           slot_name(p_slot));
 656                 break;
 657         case BLINKINGOFF_STATE:
 658         case POWEROFF_STATE:
 659                 ctrl_info(ctrl, "Already enabled on slot %s\n",
 660                           slot_name(p_slot));
 661                 break;
 662         default:
 663                 ctrl_err(ctrl, "Not a valid state on slot %s\n",
 664                          slot_name(p_slot));
 665                 break;
 666         }
 667         mutex_unlock(&p_slot->lock);
 668
 669         return retval;
 670 }
 671
 672 int shpchp_sysfs_disable_slot(struct slot *p_slot)
 673 {
 674         int retval = -ENODEV;
 675         struct controller *ctrl = p_slot->ctrl;
 676
 677         mutex_lock(&p_slot->lock);
 678         switch (p_slot->state) {
 679         case BLINKINGOFF_STATE:
 680                 cancel_delayed_work(&p_slot->work);
 681                 /* fall through */
 682         case STATIC_STATE:
 683                 p_slot->state = POWEROFF_STATE;
 684                 mutex_unlock(&p_slot->lock);
 685                 retval = shpchp_disable_slot(p_slot);
 686                 mutex_lock(&p_slot->lock);
 687                 p_slot->state = STATIC_STATE;
 688                 break;
 689         case POWEROFF_STATE:
 690                 ctrl_info(ctrl, "Slot %s is already in powering off state\n",
 691                           slot_name(p_slot));
 692                 break;
 693         case BLINKINGON_STATE:
 694         case POWERON_STATE:
 695                 ctrl_info(ctrl, "Already disabled on slot %s\n",
 696                           slot_name(p_slot));
 697                 break;
 698         default:
 699                 ctrl_err(ctrl, "Not a valid state on slot %s\n",
 700                          slot_name(p_slot));
 701                 break;
 702         }
 703         mutex_unlock(&p_slot->lock);
 704
 705         return retval;
 706 }