drivers/pci/hotplug/shpchp_core.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/moduleparam.h>
  18 #include <linux/kernel.h>
  19 #include <linux/types.h>
  20 #include <linux/slab.h>
  21 #include <linux/pci.h>
  22 #include "shpchp.h"
  23
  24 /* Global variables */
  25 bool shpchp_debug;
  26 bool shpchp_poll_mode;
  27 int shpchp_poll_time;
  28
  29 #define DRIVER_VERSION  "0.4"
  30 #define DRIVER_AUTHOR   "Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
  31 #define DRIVER_DESC     "Standard Hot Plug PCI Controller Driver"
  32
  33 MODULE_AUTHOR(DRIVER_AUTHOR);
  34 MODULE_DESCRIPTION(DRIVER_DESC);
  35 MODULE_LICENSE("GPL");
  36
  37 module_param(shpchp_debug, bool, 0644);
  38 module_param(shpchp_poll_mode, bool, 0644);
  39 module_param(shpchp_poll_time, int, 0644);
  40 MODULE_PARM_DESC(shpchp_debug, "Debugging mode enabled or not");
  41 MODULE_PARM_DESC(shpchp_poll_mode, "Using polling mechanism for hot-plug events or not");
  42 MODULE_PARM_DESC(shpchp_poll_time, "Polling mechanism frequency, in seconds");
  43
  44 #define SHPC_MODULE_NAME "shpchp"
  45
  46 static int set_attention_status(struct hotplug_slot *slot, u8 value);
  47 static int enable_slot(struct hotplug_slot *slot);
  48 static int disable_slot(struct hotplug_slot *slot);
  49 static int get_power_status(struct hotplug_slot *slot, u8 *value);
  50 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
  51 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
  52 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
  53
  54 static struct hotplug_slot_ops shpchp_hotplug_slot_ops = {
  55         .set_attention_status = set_attention_status,
  56         .enable_slot =          enable_slot,
  57         .disable_slot =         disable_slot,
  58         .get_power_status =     get_power_status,
  59         .get_attention_status = get_attention_status,
  60         .get_latch_status =     get_latch_status,
  61         .get_adapter_status =   get_adapter_status,
  62 };
  63
  64 static int init_slots(struct controller *ctrl)
  65 {
  66         struct slot *slot;
  67         struct hotplug_slot *hotplug_slot;
  68         struct hotplug_slot_info *info;
  69         char name[SLOT_NAME_SIZE];
  70         int retval;
  71         int i;
  72
  73         for (i = 0; i < ctrl->num_slots; i++) {
  74                 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
  75                 if (!slot) {
  76                         retval = -ENOMEM;
  77                         goto error;
  78                 }
  79
  80                 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
  81                 if (!hotplug_slot) {
  82                         retval = -ENOMEM;
  83                         goto error_slot;
  84                 }
  85                 slot->hotplug_slot = hotplug_slot;
  86
  87                 info = kzalloc(sizeof(*info), GFP_KERNEL);
  88                 if (!info) {
  89                         retval = -ENOMEM;
  90                         goto error_hpslot;
  91                 }
  92                 hotplug_slot->info = info;
  93
  94                 slot->hp_slot = i;
  95                 slot->ctrl = ctrl;
  96                 slot->bus = ctrl->pci_dev->subordinate->number;
  97                 slot->device = ctrl->slot_device_offset + i;
  98                 slot->hpc_ops = ctrl->hpc_ops;
  99                 slot->number = ctrl->first_slot + (ctrl->slot_num_inc * i);
 100
 101                 slot->wq = alloc_workqueue("shpchp-%d", 0, 0, slot->number);
 102                 if (!slot->wq) {
 103                         retval = -ENOMEM;
 104                         goto error_info;
 105                 }
 106
 107                 mutex_init(&slot->lock);
 108                 INIT_DELAYED_WORK(&slot->work, shpchp_queue_pushbutton_work);
 109
 110                 /* register this slot with the hotplug pci core */
 111                 hotplug_slot->private = slot;
 112                 snprintf(name, SLOT_NAME_SIZE, "%d", slot->number);
 113                 hotplug_slot->ops = &shpchp_hotplug_slot_ops;
 114
 115                 ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x hp_slot=%x sun=%x slot_device_offset=%x\n",
 116                          pci_domain_nr(ctrl->pci_dev->subordinate),
 117                          slot->bus, slot->device, slot->hp_slot, slot->number,
 118                          ctrl->slot_device_offset);
 119                 retval = pci_hp_register(slot->hotplug_slot,
 120                                 ctrl->pci_dev->subordinate, slot->device, name);
 121                 if (retval) {
 122                         ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
 123                                  retval);
 124                         goto error_slotwq;
 125                 }
 126
 127                 get_power_status(hotplug_slot, &info->power_status);
 128                 get_attention_status(hotplug_slot, &info->attention_status);
 129                 get_latch_status(hotplug_slot, &info->latch_status);
 130                 get_adapter_status(hotplug_slot, &info->adapter_status);
 131
 132                 list_add(&slot->slot_list, &ctrl->slot_list);
 133         }
 134
 135         return 0;
 136 error_slotwq:
 137         destroy_workqueue(slot->wq);
 138 error_info:
 139         kfree(info);
 140 error_hpslot:
 141         kfree(hotplug_slot);
 142 error_slot:
 143         kfree(slot);
 144 error:
 145         return retval;
 146 }
 147
 148 void cleanup_slots(struct controller *ctrl)
 149 {
 150         struct slot *slot, *next;
 151
 152         list_for_each_entry_safe(slot, next, &ctrl->slot_list, slot_list) {
 153                 list_del(&slot->slot_list);
 154                 cancel_delayed_work(&slot->work);
 155                 destroy_workqueue(slot->wq);
 156                 pci_hp_deregister(slot->hotplug_slot);
 157                 kfree(slot->hotplug_slot->info);
 158                 kfree(slot->hotplug_slot);
 159                 kfree(slot);
 160         }
 161 }
 162
 163 /*
 164  * set_attention_status - Turns the Amber LED for a slot on, off or blink
 165  */
 166 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 167 {
 168         struct slot *slot = get_slot(hotplug_slot);
 169
 170         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 171                  __func__, slot_name(slot));
 172
 173         hotplug_slot->info->attention_status = status;
 174         slot->hpc_ops->set_attention_status(slot, status);
 175
 176         return 0;
 177 }
 178
 179 static int enable_slot(struct hotplug_slot *hotplug_slot)
 180 {
 181         struct slot *slot = get_slot(hotplug_slot);
 182
 183         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 184                  __func__, slot_name(slot));
 185
 186         return shpchp_sysfs_enable_slot(slot);
 187 }
 188
 189 static int disable_slot(struct hotplug_slot *hotplug_slot)
 190 {
 191         struct slot *slot = get_slot(hotplug_slot);
 192
 193         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 194                  __func__, slot_name(slot));
 195
 196         return shpchp_sysfs_disable_slot(slot);
 197 }
 198
 199 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 200 {
 201         struct slot *slot = get_slot(hotplug_slot);
 202         int retval;
 203
 204         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 205                  __func__, slot_name(slot));
 206
 207         retval = slot->hpc_ops->get_power_status(slot, value);
 208         if (retval < 0)
 209                 *value = hotplug_slot->info->power_status;
 210
 211         return 0;
 212 }
 213
 214 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
 215 {
 216         struct slot *slot = get_slot(hotplug_slot);
 217         int retval;
 218
 219         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 220                  __func__, slot_name(slot));
 221
 222         retval = slot->hpc_ops->get_attention_status(slot, value);
 223         if (retval < 0)
 224                 *value = hotplug_slot->info->attention_status;
 225
 226         return 0;
 227 }
 228
 229 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 230 {
 231         struct slot *slot = get_slot(hotplug_slot);
 232         int retval;
 233
 234         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 235                  __func__, slot_name(slot));
 236
 237         retval = slot->hpc_ops->get_latch_status(slot, value);
 238         if (retval < 0)
 239                 *value = hotplug_slot->info->latch_status;
 240
 241         return 0;
 242 }
 243
 244 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 245 {
 246         struct slot *slot = get_slot(hotplug_slot);
 247         int retval;
 248
 249         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 250                  __func__, slot_name(slot));
 251
 252         retval = slot->hpc_ops->get_adapter_status(slot, value);
 253         if (retval < 0)
 254                 *value = hotplug_slot->info->adapter_status;
 255
 256         return 0;
 257 }
 258
 259 static bool shpc_capable(struct pci_dev *bridge)
 260 {
 261         /*
 262          * It is assumed that AMD GOLAM chips support SHPC but they do not
 263          * have SHPC capability.
 264          */
 265         if (bridge->vendor == PCI_VENDOR_ID_AMD &&
 266             bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450)
 267                 return true;
 268
 269         if (pci_find_capability(bridge, PCI_CAP_ID_SHPC))
 270                 return true;
 271
 272         return false;
 273 }
 274
 275 static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 276 {
 277         int rc;
 278         struct controller *ctrl;
 279
 280         if (!shpc_capable(pdev))
 281                 return -ENODEV;
 282
 283         if (acpi_get_hp_hw_control_from_firmware(pdev))
 284                 return -ENODEV;
 285
 286         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 287         if (!ctrl)
 288                 goto err_out_none;
 289
 290         INIT_LIST_HEAD(&ctrl->slot_list);
 291
 292         rc = shpc_init(ctrl, pdev);
 293         if (rc) {
 294                 ctrl_dbg(ctrl, "Controller initialization failed\n");
 295                 goto err_out_free_ctrl;
 296         }
 297
 298         pci_set_drvdata(pdev, ctrl);
 299
 300         /* Setup the slot information structures */
 301         rc = init_slots(ctrl);
 302         if (rc) {
 303                 ctrl_err(ctrl, "Slot initialization failed\n");
 304                 goto err_out_release_ctlr;
 305         }
 306
 307         rc = shpchp_create_ctrl_files(ctrl);
 308         if (rc)
 309                 goto err_cleanup_slots;
 310
 311         pdev->shpc_managed = 1;
 312         return 0;
 313
 314 err_cleanup_slots:
 315         cleanup_slots(ctrl);
 316 err_out_release_ctlr:
 317         ctrl->hpc_ops->release_ctlr(ctrl);
 318 err_out_free_ctrl:
 319         kfree(ctrl);
 320 err_out_none:
 321         return -ENODEV;
 322 }
 323
 324 static void shpc_remove(struct pci_dev *dev)
 325 {
 326         struct controller *ctrl = pci_get_drvdata(dev);
 327
 328         dev->shpc_managed = 0;
 329         shpchp_remove_ctrl_files(ctrl);
 330         ctrl->hpc_ops->release_ctlr(ctrl);
 331         kfree(ctrl);
 332 }
 333
 334 static const struct pci_device_id shpcd_pci_tbl[] = {
 335         {PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x00), ~0)},
 336         { /* end: all zeroes */ }
 337 };
 338 MODULE_DEVICE_TABLE(pci, shpcd_pci_tbl);
 339
 340 static struct pci_driver shpc_driver = {
 341         .name =         SHPC_MODULE_NAME,
 342         .id_table =     shpcd_pci_tbl,
 343         .probe =        shpc_probe,
 344         .remove =       shpc_remove,
 345 };
 346
 347 static int __init shpcd_init(void)
 348 {
 349         int retval;
 350
 351         retval = pci_register_driver(&shpc_driver);
 352         dbg("%s: pci_register_driver = %d\n", __func__, retval);
 353         info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
 354
 355         return retval;
 356 }
 357
 358 static void __exit shpcd_cleanup(void)
 359 {
 360         dbg("unload_shpchpd()\n");
 361         pci_unregister_driver(&shpc_driver);
 362         info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 363 }
 364
 365 module_init(shpcd_init);
 366 module_exit(shpcd_cleanup);