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 const 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         char name[SLOT_NAME_SIZE];
  69         int retval;
  70         int i;
  71
  72         for (i = 0; i < ctrl->num_slots; i++) {
  73                 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
  74                 if (!slot) {
  75                         retval = -ENOMEM;
  76                         goto error;
  77                 }
  78
  79                 hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
  80                 if (!hotplug_slot) {
  81                         retval = -ENOMEM;
  82                         goto error_slot;
  83                 }
  84                 slot->hotplug_slot = hotplug_slot;
  85
  86                 slot->hp_slot = i;
  87                 slot->ctrl = ctrl;
  88                 slot->bus = ctrl->pci_dev->subordinate->number;
  89                 slot->device = ctrl->slot_device_offset + i;
  90                 slot->hpc_ops = ctrl->hpc_ops;
  91                 slot->number = ctrl->first_slot + (ctrl->slot_num_inc * i);
  92
  93                 slot->wq = alloc_workqueue("shpchp-%d", 0, 0, slot->number);
  94                 if (!slot->wq) {
  95                         retval = -ENOMEM;
  96                         goto error_hpslot;
  97                 }
  98
  99                 mutex_init(&slot->lock);
 100                 INIT_DELAYED_WORK(&slot->work, shpchp_queue_pushbutton_work);
 101
 102                 /* register this slot with the hotplug pci core */
 103                 hotplug_slot->private = slot;
 104                 snprintf(name, SLOT_NAME_SIZE, "%d", slot->number);
 105                 hotplug_slot->ops = &shpchp_hotplug_slot_ops;
 106
 107                 ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x hp_slot=%x sun=%x slot_device_offset=%x\n",
 108                          pci_domain_nr(ctrl->pci_dev->subordinate),
 109                          slot->bus, slot->device, slot->hp_slot, slot->number,
 110                          ctrl->slot_device_offset);
 111                 retval = pci_hp_register(slot->hotplug_slot,
 112                                 ctrl->pci_dev->subordinate, slot->device, name);
 113                 if (retval) {
 114                         ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
 115                                  retval);
 116                         goto error_slotwq;
 117                 }
 118
 119                 get_power_status(hotplug_slot, &slot->pwr_save);
 120                 get_attention_status(hotplug_slot, &slot->attention_save);
 121                 get_latch_status(hotplug_slot, &slot->latch_save);
 122                 get_adapter_status(hotplug_slot, &slot->presence_save);
 123
 124                 list_add(&slot->slot_list, &ctrl->slot_list);
 125         }
 126
 127         return 0;
 128 error_slotwq:
 129         destroy_workqueue(slot->wq);
 130 error_hpslot:
 131         kfree(hotplug_slot);
 132 error_slot:
 133         kfree(slot);
 134 error:
 135         return retval;
 136 }
 137
 138 void cleanup_slots(struct controller *ctrl)
 139 {
 140         struct slot *slot, *next;
 141
 142         list_for_each_entry_safe(slot, next, &ctrl->slot_list, slot_list) {
 143                 list_del(&slot->slot_list);
 144                 cancel_delayed_work(&slot->work);
 145                 destroy_workqueue(slot->wq);
 146                 pci_hp_deregister(slot->hotplug_slot);
 147                 kfree(slot->hotplug_slot);
 148                 kfree(slot);
 149         }
 150 }
 151
 152 /*
 153  * set_attention_status - Turns the Amber LED for a slot on, off or blink
 154  */
 155 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 156 {
 157         struct slot *slot = get_slot(hotplug_slot);
 158
 159         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 160                  __func__, slot_name(slot));
 161
 162         slot->attention_save = status;
 163         slot->hpc_ops->set_attention_status(slot, status);
 164
 165         return 0;
 166 }
 167
 168 static int enable_slot(struct hotplug_slot *hotplug_slot)
 169 {
 170         struct slot *slot = get_slot(hotplug_slot);
 171
 172         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 173                  __func__, slot_name(slot));
 174
 175         return shpchp_sysfs_enable_slot(slot);
 176 }
 177
 178 static int disable_slot(struct hotplug_slot *hotplug_slot)
 179 {
 180         struct slot *slot = get_slot(hotplug_slot);
 181
 182         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 183                  __func__, slot_name(slot));
 184
 185         return shpchp_sysfs_disable_slot(slot);
 186 }
 187
 188 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 189 {
 190         struct slot *slot = get_slot(hotplug_slot);
 191         int retval;
 192
 193         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 194                  __func__, slot_name(slot));
 195
 196         retval = slot->hpc_ops->get_power_status(slot, value);
 197         if (retval < 0)
 198                 *value = slot->pwr_save;
 199
 200         return 0;
 201 }
 202
 203 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
 204 {
 205         struct slot *slot = get_slot(hotplug_slot);
 206         int retval;
 207
 208         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 209                  __func__, slot_name(slot));
 210
 211         retval = slot->hpc_ops->get_attention_status(slot, value);
 212         if (retval < 0)
 213                 *value = slot->attention_save;
 214
 215         return 0;
 216 }
 217
 218 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 219 {
 220         struct slot *slot = get_slot(hotplug_slot);
 221         int retval;
 222
 223         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 224                  __func__, slot_name(slot));
 225
 226         retval = slot->hpc_ops->get_latch_status(slot, value);
 227         if (retval < 0)
 228                 *value = slot->latch_save;
 229
 230         return 0;
 231 }
 232
 233 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 234 {
 235         struct slot *slot = get_slot(hotplug_slot);
 236         int retval;
 237
 238         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 239                  __func__, slot_name(slot));
 240
 241         retval = slot->hpc_ops->get_adapter_status(slot, value);
 242         if (retval < 0)
 243                 *value = slot->presence_save;
 244
 245         return 0;
 246 }
 247
 248 static bool shpc_capable(struct pci_dev *bridge)
 249 {
 250         /*
 251          * It is assumed that AMD GOLAM chips support SHPC but they do not
 252          * have SHPC capability.
 253          */
 254         if (bridge->vendor == PCI_VENDOR_ID_AMD &&
 255             bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450)
 256                 return true;
 257
 258         if (pci_find_capability(bridge, PCI_CAP_ID_SHPC))
 259                 return true;
 260
 261         return false;
 262 }
 263
 264 static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 265 {
 266         int rc;
 267         struct controller *ctrl;
 268
 269         if (!shpc_capable(pdev))
 270                 return -ENODEV;
 271
 272         if (acpi_get_hp_hw_control_from_firmware(pdev))
 273                 return -ENODEV;
 274
 275         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 276         if (!ctrl)
 277                 goto err_out_none;
 278
 279         INIT_LIST_HEAD(&ctrl->slot_list);
 280
 281         rc = shpc_init(ctrl, pdev);
 282         if (rc) {
 283                 ctrl_dbg(ctrl, "Controller initialization failed\n");
 284                 goto err_out_free_ctrl;
 285         }
 286
 287         pci_set_drvdata(pdev, ctrl);
 288
 289         /* Setup the slot information structures */
 290         rc = init_slots(ctrl);
 291         if (rc) {
 292                 ctrl_err(ctrl, "Slot initialization failed\n");
 293                 goto err_out_release_ctlr;
 294         }
 295
 296         rc = shpchp_create_ctrl_files(ctrl);
 297         if (rc)
 298                 goto err_cleanup_slots;
 299
 300         pdev->shpc_managed = 1;
 301         return 0;
 302
 303 err_cleanup_slots:
 304         cleanup_slots(ctrl);
 305 err_out_release_ctlr:
 306         ctrl->hpc_ops->release_ctlr(ctrl);
 307 err_out_free_ctrl:
 308         kfree(ctrl);
 309 err_out_none:
 310         return -ENODEV;
 311 }
 312
 313 static void shpc_remove(struct pci_dev *dev)
 314 {
 315         struct controller *ctrl = pci_get_drvdata(dev);
 316
 317         dev->shpc_managed = 0;
 318         shpchp_remove_ctrl_files(ctrl);
 319         ctrl->hpc_ops->release_ctlr(ctrl);
 320         kfree(ctrl);
 321 }
 322
 323 static const struct pci_device_id shpcd_pci_tbl[] = {
 324         {PCI_DEVICE_CLASS(((PCI_CLASS_BRIDGE_PCI << 8) | 0x00), ~0)},
 325         { /* end: all zeroes */ }
 326 };
 327 MODULE_DEVICE_TABLE(pci, shpcd_pci_tbl);
 328
 329 static struct pci_driver shpc_driver = {
 330         .name =         SHPC_MODULE_NAME,
 331         .id_table =     shpcd_pci_tbl,
 332         .probe =        shpc_probe,
 333         .remove =       shpc_remove,
 334 };
 335
 336 static int __init shpcd_init(void)
 337 {
 338         int retval;
 339
 340         retval = pci_register_driver(&shpc_driver);
 341         dbg("%s: pci_register_driver = %d\n", __func__, retval);
 342         info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
 343
 344         return retval;
 345 }
 346
 347 static void __exit shpcd_cleanup(void)
 348 {
 349         dbg("unload_shpchpd()\n");
 350         pci_unregister_driver(&shpc_driver);
 351         info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 352 }
 353
 354 module_init(shpcd_init);
 355 module_exit(shpcd_cleanup);