drivers/pci/hotplug/pciehp_ctrl.c

   1 /*
   2  * PCI Express Hot Plug Controller Driver
   3  *
   4  * Copyright (C) 1995,2001 Compaq Computer Corporation
   5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
   6  * Copyright (C) 2001 IBM Corp.
   7  * Copyright (C) 2003-2004 Intel Corporation
   8  *
   9  * All rights reserved.
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or (at
  14  * your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful, but
  17  * WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  19  * NON INFRINGEMENT.  See the GNU General Public License for more
  20  * details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25  *
  26  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
  27  *
  28  */
  29
  30 #include <linux/module.h>
  31 #include <linux/kernel.h>
  32 #include <linux/types.h>
  33 #include <linux/slab.h>
  34 #include <linux/pci.h>
  35 #include "../pci.h"
  36 #include "pciehp.h"
  37
  38 static void interrupt_event_handler(struct work_struct *work);
  39
  40 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
  41 {
  42         struct event_info *info;
  43
  44         info = kmalloc(sizeof(*info), GFP_ATOMIC);
  45         if (!info)
  46                 return -ENOMEM;
  47
  48         info->event_type = event_type;
  49         info->p_slot = p_slot;
  50         INIT_WORK(&info->work, interrupt_event_handler);
  51
  52         queue_work(p_slot->wq, &info->work);
  53
  54         return 0;
  55 }
  56
  57 u8 pciehp_handle_attention_button(struct slot *p_slot)
  58 {
  59         u32 event_type;
  60         struct controller *ctrl = p_slot->ctrl;
  61
  62         /* Attention Button Change */
  63         ctrl_dbg(ctrl, "Attention button interrupt received\n");
  64
  65         /*
  66          *  Button pressed - See if need to TAKE ACTION!!!
  67          */
  68         ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
  69         event_type = INT_BUTTON_PRESS;
  70
  71         queue_interrupt_event(p_slot, event_type);
  72
  73         return 0;
  74 }
  75
  76 u8 pciehp_handle_switch_change(struct slot *p_slot)
  77 {
  78         u8 getstatus;
  79         u32 event_type;
  80         struct controller *ctrl = p_slot->ctrl;
  81
  82         /* Switch Change */
  83         ctrl_dbg(ctrl, "Switch interrupt received\n");
  84
  85         pciehp_get_latch_status(p_slot, &getstatus);
  86         if (getstatus) {
  87                 /*
  88                  * Switch opened
  89                  */
  90                 ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
  91                 event_type = INT_SWITCH_OPEN;
  92         } else {
  93                 /*
  94                  *  Switch closed
  95                  */
  96                 ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
  97                 event_type = INT_SWITCH_CLOSE;
  98         }
  99
 100         queue_interrupt_event(p_slot, event_type);
 101
 102         return 1;
 103 }
 104
 105 u8 pciehp_handle_presence_change(struct slot *p_slot)
 106 {
 107         u32 event_type;
 108         u8 presence_save;
 109         struct controller *ctrl = p_slot->ctrl;
 110
 111         /* Presence Change */
 112         ctrl_dbg(ctrl, "Presence/Notify input change\n");
 113
 114         /* Switch is open, assume a presence change
 115          * Save the presence state
 116          */
 117         pciehp_get_adapter_status(p_slot, &presence_save);
 118         if (presence_save) {
 119                 /*
 120                  * Card Present
 121                  */
 122                 ctrl_info(ctrl, "Card present on Slot(%s)\n", slot_name(p_slot));
 123                 event_type = INT_PRESENCE_ON;
 124         } else {
 125                 /*
 126                  * Not Present
 127                  */
 128                 ctrl_info(ctrl, "Card not present on Slot(%s)\n",
 129                           slot_name(p_slot));
 130                 event_type = INT_PRESENCE_OFF;
 131         }
 132
 133         queue_interrupt_event(p_slot, event_type);
 134
 135         return 1;
 136 }
 137
 138 u8 pciehp_handle_power_fault(struct slot *p_slot)
 139 {
 140         u32 event_type;
 141         struct controller *ctrl = p_slot->ctrl;
 142
 143         /* power fault */
 144         ctrl_dbg(ctrl, "Power fault interrupt received\n");
 145         ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 146         event_type = INT_POWER_FAULT;
 147         ctrl_info(ctrl, "Power fault bit %x set\n", 0);
 148         queue_interrupt_event(p_slot, event_type);
 149
 150         return 1;
 151 }
 152
 153 void pciehp_handle_linkstate_change(struct slot *p_slot)
 154 {
 155         u32 event_type;
 156         struct controller *ctrl = p_slot->ctrl;
 157
 158         /* Link Status Change */
 159         ctrl_dbg(ctrl, "Data Link Layer State change\n");
 160
 161         if (pciehp_check_link_active(ctrl)) {
 162                 ctrl_info(ctrl, "slot(%s): Link Up event\n",
 163                           slot_name(p_slot));
 164                 event_type = INT_LINK_UP;
 165         } else {
 166                 ctrl_info(ctrl, "slot(%s): Link Down event\n",
 167                           slot_name(p_slot));
 168                 event_type = INT_LINK_DOWN;
 169         }
 170
 171         queue_interrupt_event(p_slot, event_type);
 172 }
 173
 174 /* The following routines constitute the bulk of the
 175    hotplug controller logic
 176  */
 177
 178 static void set_slot_off(struct controller *ctrl, struct slot *pslot)
 179 {
 180         /* turn off slot, turn on Amber LED, turn off Green LED if supported*/
 181         if (POWER_CTRL(ctrl)) {
 182                 pciehp_power_off_slot(pslot);
 183
 184                 /*
 185                  * After turning power off, we must wait for at least 1 second
 186                  * before taking any action that relies on power having been
 187                  * removed from the slot/adapter.
 188                  */
 189                 msleep(1000);
 190         }
 191
 192         pciehp_green_led_off(pslot);
 193         pciehp_set_attention_status(pslot, 1);
 194 }
 195
 196 /**
 197  * board_added - Called after a board has been added to the system.
 198  * @p_slot: &slot where board is added
 199  *
 200  * Turns power on for the board.
 201  * Configures board.
 202  */
 203 static int board_added(struct slot *p_slot)
 204 {
 205         int retval = 0;
 206         struct controller *ctrl = p_slot->ctrl;
 207         struct pci_bus *parent = ctrl->pcie->port->subordinate;
 208
 209         if (POWER_CTRL(ctrl)) {
 210                 /* Power on slot */
 211                 retval = pciehp_power_on_slot(p_slot);
 212                 if (retval)
 213                         return retval;
 214         }
 215
 216         pciehp_green_led_blink(p_slot);
 217
 218         /* Check link training status */
 219         retval = pciehp_check_link_status(ctrl);
 220         if (retval) {
 221                 ctrl_err(ctrl, "Failed to check link status\n");
 222                 goto err_exit;
 223         }
 224
 225         /* Check for a power fault */
 226         if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
 227                 ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
 228                 retval = -EIO;
 229                 goto err_exit;
 230         }
 231
 232         retval = pciehp_configure_device(p_slot);
 233         if (retval) {
 234                 ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
 235                          pci_domain_nr(parent), parent->number);
 236                 if (retval != -EEXIST)
 237                         goto err_exit;
 238         }
 239
 240         pciehp_green_led_on(p_slot);
 241         return 0;
 242
 243 err_exit:
 244         set_slot_off(ctrl, p_slot);
 245         return retval;
 246 }
 247
 248 /**
 249  * remove_board - Turns off slot and LEDs
 250  * @p_slot: slot where board is being removed
 251  */
 252 static int remove_board(struct slot *p_slot)
 253 {
 254         int retval;
 255         struct controller *ctrl = p_slot->ctrl;
 256
 257         retval = pciehp_unconfigure_device(p_slot);
 258         if (retval)
 259                 return retval;
 260
 261         if (POWER_CTRL(ctrl)) {
 262                 pciehp_power_off_slot(p_slot);
 263
 264                 /*
 265                  * After turning power off, we must wait for at least 1 second
 266                  * before taking any action that relies on power having been
 267                  * removed from the slot/adapter.
 268                  */
 269                 msleep(1000);
 270         }
 271
 272         /* turn off Green LED */
 273         pciehp_green_led_off(p_slot);
 274         return 0;
 275 }
 276
 277 struct power_work_info {
 278         struct slot *p_slot;
 279         struct work_struct work;
 280         unsigned int req;
 281 #define DISABLE_REQ 0
 282 #define ENABLE_REQ  1
 283 };
 284
 285 /**
 286  * pciehp_power_thread - handle pushbutton events
 287  * @work: &struct work_struct describing work to be done
 288  *
 289  * Scheduled procedure to handle blocking stuff for the pushbuttons.
 290  * Handles all pending events and exits.
 291  */
 292 static void pciehp_power_thread(struct work_struct *work)
 293 {
 294         struct power_work_info *info =
 295                 container_of(work, struct power_work_info, work);
 296         struct slot *p_slot = info->p_slot;
 297         int ret;
 298
 299         switch (info->req) {
 300         case DISABLE_REQ:
 301                 ctrl_dbg(p_slot->ctrl,
 302                          "Disabling domain:bus:device=%04x:%02x:00\n",
 303                          pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
 304                          p_slot->ctrl->pcie->port->subordinate->number);
 305                 mutex_lock(&p_slot->hotplug_lock);
 306                 pciehp_disable_slot(p_slot);
 307                 mutex_unlock(&p_slot->hotplug_lock);
 308                 mutex_lock(&p_slot->lock);
 309                 p_slot->state = STATIC_STATE;
 310                 mutex_unlock(&p_slot->lock);
 311                 break;
 312         case ENABLE_REQ:
 313                 ctrl_dbg(p_slot->ctrl,
 314                          "Enabling domain:bus:device=%04x:%02x:00\n",
 315                          pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
 316                          p_slot->ctrl->pcie->port->subordinate->number);
 317                 mutex_lock(&p_slot->hotplug_lock);
 318                 ret = pciehp_enable_slot(p_slot);
 319                 mutex_unlock(&p_slot->hotplug_lock);
 320                 if (ret)
 321                         pciehp_green_led_off(p_slot);
 322                 mutex_lock(&p_slot->lock);
 323                 p_slot->state = STATIC_STATE;
 324                 mutex_unlock(&p_slot->lock);
 325                 break;
 326         default:
 327                 break;
 328         }
 329
 330         kfree(info);
 331 }
 332
 333 void pciehp_queue_pushbutton_work(struct work_struct *work)
 334 {
 335         struct slot *p_slot = container_of(work, struct slot, work.work);
 336         struct power_work_info *info;
 337
 338         info = kmalloc(sizeof(*info), GFP_KERNEL);
 339         if (!info) {
 340                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 341                          __func__);
 342                 return;
 343         }
 344         info->p_slot = p_slot;
 345         INIT_WORK(&info->work, pciehp_power_thread);
 346
 347         mutex_lock(&p_slot->lock);
 348         switch (p_slot->state) {
 349         case BLINKINGOFF_STATE:
 350                 p_slot->state = POWEROFF_STATE;
 351                 info->req = DISABLE_REQ;
 352                 break;
 353         case BLINKINGON_STATE:
 354                 p_slot->state = POWERON_STATE;
 355                 info->req = ENABLE_REQ;
 356                 break;
 357         default:
 358                 kfree(info);
 359                 goto out;
 360         }
 361         queue_work(p_slot->wq, &info->work);
 362  out:
 363         mutex_unlock(&p_slot->lock);
 364 }
 365
 366 /*
 367  * Note: This function must be called with slot->lock held
 368  */
 369 static void handle_button_press_event(struct slot *p_slot)
 370 {
 371         struct controller *ctrl = p_slot->ctrl;
 372         u8 getstatus;
 373
 374         switch (p_slot->state) {
 375         case STATIC_STATE:
 376                 pciehp_get_power_status(p_slot, &getstatus);
 377                 if (getstatus) {
 378                         p_slot->state = BLINKINGOFF_STATE;
 379                         ctrl_info(ctrl,
 380                                   "PCI slot #%s - powering off due to button "
 381                                   "press.\n", slot_name(p_slot));
 382                 } else {
 383                         p_slot->state = BLINKINGON_STATE;
 384                         ctrl_info(ctrl,
 385                                   "PCI slot #%s - powering on due to button "
 386                                   "press.\n", slot_name(p_slot));
 387                 }
 388                 /* blink green LED and turn off amber */
 389                 pciehp_green_led_blink(p_slot);
 390                 pciehp_set_attention_status(p_slot, 0);
 391                 queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
 392                 break;
 393         case BLINKINGOFF_STATE:
 394         case BLINKINGON_STATE:
 395                 /*
 396                  * Cancel if we are still blinking; this means that we
 397                  * press the attention again before the 5 sec. limit
 398                  * expires to cancel hot-add or hot-remove
 399                  */
 400                 ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
 401                 cancel_delayed_work(&p_slot->work);
 402                 if (p_slot->state == BLINKINGOFF_STATE)
 403                         pciehp_green_led_on(p_slot);
 404                 else
 405                         pciehp_green_led_off(p_slot);
 406                 pciehp_set_attention_status(p_slot, 0);
 407                 ctrl_info(ctrl, "PCI slot #%s - action canceled "
 408                           "due to button press\n", slot_name(p_slot));
 409                 p_slot->state = STATIC_STATE;
 410                 break;
 411         case POWEROFF_STATE:
 412         case POWERON_STATE:
 413                 /*
 414                  * Ignore if the slot is on power-on or power-off state;
 415                  * this means that the previous attention button action
 416                  * to hot-add or hot-remove is undergoing
 417                  */
 418                 ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
 419                 break;
 420         default:
 421                 ctrl_warn(ctrl, "Not a valid state\n");
 422                 break;
 423         }
 424 }
 425
 426 /*
 427  * Note: This function must be called with slot->lock held
 428  */
 429 static void handle_surprise_event(struct slot *p_slot)
 430 {
 431         u8 getstatus;
 432         struct power_work_info *info;
 433
 434         info = kmalloc(sizeof(*info), GFP_KERNEL);
 435         if (!info) {
 436                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 437                          __func__);
 438                 return;
 439         }
 440         info->p_slot = p_slot;
 441         INIT_WORK(&info->work, pciehp_power_thread);
 442
 443         pciehp_get_adapter_status(p_slot, &getstatus);
 444         if (!getstatus) {
 445                 p_slot->state = POWEROFF_STATE;
 446                 info->req = DISABLE_REQ;
 447         } else {
 448                 p_slot->state = POWERON_STATE;
 449                 info->req = ENABLE_REQ;
 450         }
 451
 452         queue_work(p_slot->wq, &info->work);
 453 }
 454
 455 /*
 456  * Note: This function must be called with slot->lock held
 457  */
 458 static void handle_link_event(struct slot *p_slot, u32 event)
 459 {
 460         struct controller *ctrl = p_slot->ctrl;
 461         struct power_work_info *info;
 462
 463         info = kmalloc(sizeof(*info), GFP_KERNEL);
 464         if (!info) {
 465                 ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
 466                          __func__);
 467                 return;
 468         }
 469         info->p_slot = p_slot;
 470         info->req = event == INT_LINK_UP ? ENABLE_REQ : DISABLE_REQ;
 471         INIT_WORK(&info->work, pciehp_power_thread);
 472
 473         switch (p_slot->state) {
 474         case BLINKINGON_STATE:
 475         case BLINKINGOFF_STATE:
 476                 cancel_delayed_work(&p_slot->work);
 477                 /* Fall through */
 478         case STATIC_STATE:
 479                 p_slot->state = event == INT_LINK_UP ?
 480                     POWERON_STATE : POWEROFF_STATE;
 481                 queue_work(p_slot->wq, &info->work);
 482                 break;
 483         case POWERON_STATE:
 484                 if (event == INT_LINK_UP) {
 485                         ctrl_info(ctrl,
 486                                   "Link Up event ignored on slot(%s): already powering on\n",
 487                                   slot_name(p_slot));
 488                         kfree(info);
 489                 } else {
 490                         ctrl_info(ctrl,
 491                                   "Link Down event queued on slot(%s): currently getting powered on\n",
 492                                   slot_name(p_slot));
 493                         p_slot->state = POWEROFF_STATE;
 494                         queue_work(p_slot->wq, &info->work);
 495                 }
 496                 break;
 497         case POWEROFF_STATE:
 498                 if (event == INT_LINK_UP) {
 499                         ctrl_info(ctrl,
 500                                   "Link Up event queued on slot(%s): currently getting powered off\n",
 501                                   slot_name(p_slot));
 502                         p_slot->state = POWERON_STATE;
 503                         queue_work(p_slot->wq, &info->work);
 504                 } else {
 505                         ctrl_info(ctrl,
 506                                   "Link Down event ignored on slot(%s): already powering off\n",
 507                                   slot_name(p_slot));
 508                         kfree(info);
 509                 }
 510                 break;
 511         default:
 512                 ctrl_err(ctrl, "Not a valid state on slot(%s)\n",
 513                          slot_name(p_slot));
 514                 kfree(info);
 515                 break;
 516         }
 517 }
 518
 519 static void interrupt_event_handler(struct work_struct *work)
 520 {
 521         struct event_info *info = container_of(work, struct event_info, work);
 522         struct slot *p_slot = info->p_slot;
 523         struct controller *ctrl = p_slot->ctrl;
 524
 525         mutex_lock(&p_slot->lock);
 526         switch (info->event_type) {
 527         case INT_BUTTON_PRESS:
 528                 handle_button_press_event(p_slot);
 529                 break;
 530         case INT_POWER_FAULT:
 531                 if (!POWER_CTRL(ctrl))
 532                         break;
 533                 pciehp_set_attention_status(p_slot, 1);
 534                 pciehp_green_led_off(p_slot);
 535                 break;
 536         case INT_PRESENCE_ON:
 537                 if (!HP_SUPR_RM(ctrl))
 538                         break;
 539                 ctrl_dbg(ctrl, "Surprise Insertion\n");
 540                 handle_surprise_event(p_slot);
 541                 break;
 542         case INT_PRESENCE_OFF:
 543                 /*
 544                  * Regardless of surprise capability, we need to
 545                  * definitely remove a card that has been pulled out!
 546                  */
 547                 ctrl_dbg(ctrl, "Surprise Removal\n");
 548                 handle_surprise_event(p_slot);
 549                 break;
 550         case INT_LINK_UP:
 551         case INT_LINK_DOWN:
 552                 handle_link_event(p_slot, info->event_type);
 553                 break;
 554         default:
 555                 break;
 556         }
 557         mutex_unlock(&p_slot->lock);
 558
 559         kfree(info);
 560 }
 561
 562 /*
 563  * Note: This function must be called with slot->hotplug_lock held
 564  */
 565 int pciehp_enable_slot(struct slot *p_slot)
 566 {
 567         u8 getstatus = 0;
 568         int rc;
 569         struct controller *ctrl = p_slot->ctrl;
 570
 571         pciehp_get_adapter_status(p_slot, &getstatus);
 572         if (!getstatus) {
 573                 ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
 574                 return -ENODEV;
 575         }
 576         if (MRL_SENS(p_slot->ctrl)) {
 577                 pciehp_get_latch_status(p_slot, &getstatus);
 578                 if (getstatus) {
 579                         ctrl_info(ctrl, "Latch open on slot(%s)\n",
 580                                   slot_name(p_slot));
 581                         return -ENODEV;
 582                 }
 583         }
 584
 585         if (POWER_CTRL(p_slot->ctrl)) {
 586                 pciehp_get_power_status(p_slot, &getstatus);
 587                 if (getstatus) {
 588                         ctrl_info(ctrl, "Already enabled on slot(%s)\n",
 589                                   slot_name(p_slot));
 590                         return -EINVAL;
 591                 }
 592         }
 593
 594         pciehp_get_latch_status(p_slot, &getstatus);
 595
 596         rc = board_added(p_slot);
 597         if (rc)
 598                 pciehp_get_latch_status(p_slot, &getstatus);
 599
 600         return rc;
 601 }
 602
 603 /*
 604  * Note: This function must be called with slot->hotplug_lock held
 605  */
 606 int pciehp_disable_slot(struct slot *p_slot)
 607 {
 608         u8 getstatus = 0;
 609         struct controller *ctrl = p_slot->ctrl;
 610
 611         if (!p_slot->ctrl)
 612                 return 1;
 613
 614         if (POWER_CTRL(p_slot->ctrl)) {
 615                 pciehp_get_power_status(p_slot, &getstatus);
 616                 if (!getstatus) {
 617                         ctrl_info(ctrl, "Already disabled on slot(%s)\n",
 618                                   slot_name(p_slot));
 619                         return -EINVAL;
 620                 }
 621         }
 622
 623         return remove_board(p_slot);
 624 }
 625
 626 int pciehp_sysfs_enable_slot(struct slot *p_slot)
 627 {
 628         int retval = -ENODEV;
 629         struct controller *ctrl = p_slot->ctrl;
 630
 631         mutex_lock(&p_slot->lock);
 632         switch (p_slot->state) {
 633         case BLINKINGON_STATE:
 634                 cancel_delayed_work(&p_slot->work);
 635         case STATIC_STATE:
 636                 p_slot->state = POWERON_STATE;
 637                 mutex_unlock(&p_slot->lock);
 638                 mutex_lock(&p_slot->hotplug_lock);
 639                 retval = pciehp_enable_slot(p_slot);
 640                 mutex_unlock(&p_slot->hotplug_lock);
 641                 mutex_lock(&p_slot->lock);
 642                 p_slot->state = STATIC_STATE;
 643                 break;
 644         case POWERON_STATE:
 645                 ctrl_info(ctrl, "Slot %s is already in powering on state\n",
 646                           slot_name(p_slot));
 647                 break;
 648         case BLINKINGOFF_STATE:
 649         case POWEROFF_STATE:
 650                 ctrl_info(ctrl, "Already enabled on slot %s\n",
 651                           slot_name(p_slot));
 652                 break;
 653         default:
 654                 ctrl_err(ctrl, "Not a valid state on slot %s\n",
 655                          slot_name(p_slot));
 656                 break;
 657         }
 658         mutex_unlock(&p_slot->lock);
 659
 660         return retval;
 661 }
 662
 663 int pciehp_sysfs_disable_slot(struct slot *p_slot)
 664 {
 665         int retval = -ENODEV;
 666         struct controller *ctrl = p_slot->ctrl;
 667
 668         mutex_lock(&p_slot->lock);
 669         switch (p_slot->state) {
 670         case BLINKINGOFF_STATE:
 671                 cancel_delayed_work(&p_slot->work);
 672         case STATIC_STATE:
 673                 p_slot->state = POWEROFF_STATE;
 674                 mutex_unlock(&p_slot->lock);
 675                 retval = pciehp_disable_slot(p_slot);
 676                 mutex_lock(&p_slot->lock);
 677                 p_slot->state = STATIC_STATE;
 678                 break;
 679         case POWEROFF_STATE:
 680                 ctrl_info(ctrl, "Slot %s is already in powering off state\n",
 681                           slot_name(p_slot));
 682                 break;
 683         case BLINKINGON_STATE:
 684         case POWERON_STATE:
 685                 ctrl_info(ctrl, "Already disabled on slot %s\n",
 686                           slot_name(p_slot));
 687                 break;
 688         default:
 689                 ctrl_err(ctrl, "Not a valid state on slot %s\n",
 690                          slot_name(p_slot));
 691                 break;
 692         }
 693         mutex_unlock(&p_slot->lock);
 694
 695         return retval;
 696 }