drivers/pci/hotplug/acpiphp_core.c

   1 /*
   2  * ACPI PCI 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) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com)
   8  * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com)
   9  * Copyright (C) 2002,2003 NEC Corporation
  10  * Copyright (C) 2003-2005 Matthew Wilcox (matthew.wilcox@hp.com)
  11  * Copyright (C) 2003-2005 Hewlett Packard
  12  *
  13  * All rights reserved.
  14  *
  15  * This program is free software; you can redistribute it and/or modify
  16  * it under the terms of the GNU General Public License as published by
  17  * the Free Software Foundation; either version 2 of the License, or (at
  18  * your option) any later version.
  19  *
  20  * This program is distributed in the hope that it will be useful, but
  21  * WITHOUT ANY WARRANTY; without even the implied warranty of
  22  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  23  * NON INFRINGEMENT.  See the GNU General Public License for more
  24  * details.
  25  *
  26  * You should have received a copy of the GNU General Public License
  27  * along with this program; if not, write to the Free Software
  28  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29  *
  30  * Send feedback to <kristen.c.accardi@intel.com>
  31  *
  32  */
  33
  34 #define pr_fmt(fmt) "acpiphp: " fmt
  35
  36 #include <linux/init.h>
  37 #include <linux/module.h>
  38 #include <linux/moduleparam.h>
  39
  40 #include <linux/kernel.h>
  41 #include <linux/pci.h>
  42 #include <linux/pci-acpi.h>
  43 #include <linux/pci_hotplug.h>
  44 #include <linux/slab.h>
  45 #include <linux/smp.h>
  46 #include "acpiphp.h"
  47
  48 /* name size which is used for entries in pcihpfs */
  49 #define SLOT_NAME_SIZE  21              /* {_SUN} */
  50
  51 bool acpiphp_disabled;
  52
  53 /* local variables */
  54 static struct acpiphp_attention_info *attention_info;
  55
  56 #define DRIVER_VERSION  "0.5"
  57 #define DRIVER_AUTHOR   "Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@hp.com>"
  58 #define DRIVER_DESC     "ACPI Hot Plug PCI Controller Driver"
  59
  60 MODULE_AUTHOR(DRIVER_AUTHOR);
  61 MODULE_DESCRIPTION(DRIVER_DESC);
  62 MODULE_LICENSE("GPL");
  63 MODULE_PARM_DESC(disable, "disable acpiphp driver");
  64 module_param_named(disable, acpiphp_disabled, bool, 0444);
  65
  66 /* export the attention callback registration methods */
  67 EXPORT_SYMBOL_GPL(acpiphp_register_attention);
  68 EXPORT_SYMBOL_GPL(acpiphp_unregister_attention);
  69
  70 static int enable_slot          (struct hotplug_slot *slot);
  71 static int disable_slot         (struct hotplug_slot *slot);
  72 static int set_attention_status (struct hotplug_slot *slot, u8 value);
  73 static int get_power_status     (struct hotplug_slot *slot, u8 *value);
  74 static int get_attention_status (struct hotplug_slot *slot, u8 *value);
  75 static int get_latch_status     (struct hotplug_slot *slot, u8 *value);
  76 static int get_adapter_status   (struct hotplug_slot *slot, u8 *value);
  77
  78 static struct hotplug_slot_ops acpi_hotplug_slot_ops = {
  79         .enable_slot            = enable_slot,
  80         .disable_slot           = disable_slot,
  81         .set_attention_status   = set_attention_status,
  82         .get_power_status       = get_power_status,
  83         .get_attention_status   = get_attention_status,
  84         .get_latch_status       = get_latch_status,
  85         .get_adapter_status     = get_adapter_status,
  86 };
  87
  88 /**
  89  * acpiphp_register_attention - set attention LED callback
  90  * @info: must be completely filled with LED callbacks
  91  *
  92  * Description: This is used to register a hardware specific ACPI
  93  * driver that manipulates the attention LED.  All the fields in
  94  * info must be set.
  95  */
  96 int acpiphp_register_attention(struct acpiphp_attention_info *info)
  97 {
  98         int retval = -EINVAL;
  99
 100         if (info && info->owner && info->set_attn &&
 101                         info->get_attn && !attention_info) {
 102                 retval = 0;
 103                 attention_info = info;
 104         }
 105         return retval;
 106 }
 107
 108
 109 /**
 110  * acpiphp_unregister_attention - unset attention LED callback
 111  * @info: must match the pointer used to register
 112  *
 113  * Description: This is used to un-register a hardware specific acpi
 114  * driver that manipulates the attention LED.  The pointer to the
 115  * info struct must be the same as the one used to set it.
 116  */
 117 int acpiphp_unregister_attention(struct acpiphp_attention_info *info)
 118 {
 119         int retval = -EINVAL;
 120
 121         if (info && attention_info == info) {
 122                 attention_info = NULL;
 123                 retval = 0;
 124         }
 125         return retval;
 126 }
 127
 128
 129 /**
 130  * enable_slot - power on and enable a slot
 131  * @hotplug_slot: slot to enable
 132  *
 133  * Actual tasks are done in acpiphp_enable_slot()
 134  */
 135 static int enable_slot(struct hotplug_slot *hotplug_slot)
 136 {
 137         struct slot *slot = hotplug_slot->private;
 138
 139         pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
 140
 141         /* enable the specified slot */
 142         return acpiphp_enable_slot(slot->acpi_slot);
 143 }
 144
 145
 146 /**
 147  * disable_slot - disable and power off a slot
 148  * @hotplug_slot: slot to disable
 149  *
 150  * Actual tasks are done in acpiphp_disable_slot()
 151  */
 152 static int disable_slot(struct hotplug_slot *hotplug_slot)
 153 {
 154         struct slot *slot = hotplug_slot->private;
 155
 156         pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
 157
 158         /* disable the specified slot */
 159         return acpiphp_disable_slot(slot->acpi_slot);
 160 }
 161
 162
 163 /**
 164  * set_attention_status - set attention LED
 165  * @hotplug_slot: slot to set attention LED on
 166  * @status: value to set attention LED to (0 or 1)
 167  *
 168  * attention status LED, so we use a callback that
 169  * was registered with us.  This allows hardware specific
 170  * ACPI implementations to blink the light for us.
 171  */
 172 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 173 {
 174         int retval = -ENODEV;
 175
 176         pr_debug("%s - physical_slot = %s\n", __func__,
 177                 hotplug_slot_name(hotplug_slot));
 178
 179         if (attention_info && try_module_get(attention_info->owner)) {
 180                 retval = attention_info->set_attn(hotplug_slot, status);
 181                 module_put(attention_info->owner);
 182         } else
 183                 attention_info = NULL;
 184         return retval;
 185 }
 186
 187
 188 /**
 189  * get_power_status - get power status of a slot
 190  * @hotplug_slot: slot to get status
 191  * @value: pointer to store status
 192  *
 193  * Some platforms may not implement _STA method properly.
 194  * In that case, the value returned may not be reliable.
 195  */
 196 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 197 {
 198         struct slot *slot = hotplug_slot->private;
 199
 200         pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
 201
 202         *value = acpiphp_get_power_status(slot->acpi_slot);
 203
 204         return 0;
 205 }
 206
 207
 208 /**
 209  * get_attention_status - get attention LED status
 210  * @hotplug_slot: slot to get status from
 211  * @value: returns with value of attention LED
 212  *
 213  * ACPI doesn't have known method to determine the state
 214  * of the attention status LED, so we use a callback that
 215  * was registered with us.  This allows hardware specific
 216  * ACPI implementations to determine its state.
 217  */
 218 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
 219 {
 220         int retval = -EINVAL;
 221
 222         pr_debug("%s - physical_slot = %s\n", __func__,
 223                 hotplug_slot_name(hotplug_slot));
 224
 225         if (attention_info && try_module_get(attention_info->owner)) {
 226                 retval = attention_info->get_attn(hotplug_slot, value);
 227                 module_put(attention_info->owner);
 228         } else
 229                 attention_info = NULL;
 230         return retval;
 231 }
 232
 233
 234 /**
 235  * get_latch_status - get latch status of a slot
 236  * @hotplug_slot: slot to get status
 237  * @value: pointer to store status
 238  *
 239  * ACPI doesn't provide any formal means to access latch status.
 240  * Instead, we fake latch status from _STA.
 241  */
 242 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 243 {
 244         struct slot *slot = hotplug_slot->private;
 245
 246         pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
 247
 248         *value = acpiphp_get_latch_status(slot->acpi_slot);
 249
 250         return 0;
 251 }
 252
 253
 254 /**
 255  * get_adapter_status - get adapter status of a slot
 256  * @hotplug_slot: slot to get status
 257  * @value: pointer to store status
 258  *
 259  * ACPI doesn't provide any formal means to access adapter status.
 260  * Instead, we fake adapter status from _STA.
 261  */
 262 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 263 {
 264         struct slot *slot = hotplug_slot->private;
 265
 266         pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
 267
 268         *value = acpiphp_get_adapter_status(slot->acpi_slot);
 269
 270         return 0;
 271 }
 272
 273 /**
 274  * release_slot - free up the memory used by a slot
 275  * @hotplug_slot: slot to free
 276  */
 277 static void release_slot(struct hotplug_slot *hotplug_slot)
 278 {
 279         struct slot *slot = hotplug_slot->private;
 280
 281         pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot));
 282
 283         kfree(slot->hotplug_slot);
 284         kfree(slot);
 285 }
 286
 287 /* callback routine to initialize 'struct slot' for each slot */
 288 int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot,
 289                                   unsigned int sun)
 290 {
 291         struct slot *slot;
 292         int retval = -ENOMEM;
 293         char name[SLOT_NAME_SIZE];
 294
 295         slot = kzalloc(sizeof(*slot), GFP_KERNEL);
 296         if (!slot)
 297                 goto error;
 298
 299         slot->hotplug_slot = kzalloc(sizeof(*slot->hotplug_slot), GFP_KERNEL);
 300         if (!slot->hotplug_slot)
 301                 goto error_slot;
 302
 303         slot->hotplug_slot->info = &slot->info;
 304
 305         slot->hotplug_slot->private = slot;
 306         slot->hotplug_slot->release = &release_slot;
 307         slot->hotplug_slot->ops = &acpi_hotplug_slot_ops;
 308
 309         slot->acpi_slot = acpiphp_slot;
 310         slot->hotplug_slot->info->power_status = acpiphp_get_power_status(slot->acpi_slot);
 311         slot->hotplug_slot->info->attention_status = 0;
 312         slot->hotplug_slot->info->latch_status = acpiphp_get_latch_status(slot->acpi_slot);
 313         slot->hotplug_slot->info->adapter_status = acpiphp_get_adapter_status(slot->acpi_slot);
 314
 315         acpiphp_slot->slot = slot;
 316         slot->sun = sun;
 317         snprintf(name, SLOT_NAME_SIZE, "%u", sun);
 318
 319         retval = pci_hp_register(slot->hotplug_slot, acpiphp_slot->bus,
 320                                  acpiphp_slot->device, name);
 321         if (retval == -EBUSY)
 322                 goto error_hpslot;
 323         if (retval) {
 324                 pr_err("pci_hp_register failed with error %d\n", retval);
 325                 goto error_hpslot;
 326         }
 327
 328         pr_info("Slot [%s] registered\n", slot_name(slot));
 329
 330         return 0;
 331 error_hpslot:
 332         kfree(slot->hotplug_slot);
 333 error_slot:
 334         kfree(slot);
 335 error:
 336         return retval;
 337 }
 338
 339
 340 void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot)
 341 {
 342         struct slot *slot = acpiphp_slot->slot;
 343         int retval = 0;
 344
 345         pr_info("Slot [%s] unregistered\n", slot_name(slot));
 346
 347         retval = pci_hp_deregister(slot->hotplug_slot);
 348         if (retval)
 349                 pr_err("pci_hp_deregister failed with error %d\n", retval);
 350 }
 351
 352
 353 void __init acpiphp_init(void)
 354 {
 355         pr_info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n",
 356                 acpiphp_disabled ? ", disabled by user; please report a bug"
 357                                  : "");
 358 }