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 ([email protected])
   7  * Copyright (C) 2001 IBM Corp.
   8  * Copyright (C) 2003-2004 Intel Corporation
   9  *
  10  * All rights reserved.
  11  *
  12  * Send feedback to <[email protected]>, <[email protected]>
  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 <[email protected]>, Greg Kroah-Hartman <[email protected]>, Dely Sy <[email protected]>"
  31 #define DRIVER_DESC     "Standard Hot Plug PCI Controller Driver"
  32
  33 MODULE_AUTHOR(DRIVER_AUTHOR);
  34 MODULE_DESCRIPTION(DRIVER_DESC);
  35
  36 module_param(shpchp_debug, bool, 0644);
  37 module_param(shpchp_poll_mode, bool, 0644);
  38 module_param(shpchp_poll_time, int, 0644);
  39 MODULE_PARM_DESC(shpchp_debug, "Debugging mode enabled or not");
  40 MODULE_PARM_DESC(shpchp_poll_mode, "Using polling mechanism for hot-plug events or not");
  41 MODULE_PARM_DESC(shpchp_poll_time, "Polling mechanism frequency, in seconds");
  42
  43 #define SHPC_MODULE_NAME "shpchp"
  44
  45 static int set_attention_status(struct hotplug_slot *slot, u8 value);
  46 static int enable_slot(struct hotplug_slot *slot);
  47 static int disable_slot(struct hotplug_slot *slot);
  48 static int get_power_status(struct hotplug_slot *slot, u8 *value);
  49 static int get_attention_status(struct hotplug_slot *slot, u8 *value);
  50 static int get_latch_status(struct hotplug_slot *slot, u8 *value);
  51 static int get_adapter_status(struct hotplug_slot *slot, u8 *value);
  52
  53 static const struct hotplug_slot_ops shpchp_hotplug_slot_ops = {
  54         .set_attention_status = set_attention_status,
  55         .enable_slot =          enable_slot,
  56         .disable_slot =         disable_slot,
  57         .get_power_status =     get_power_status,
  58         .get_attention_status = get_attention_status,
  59         .get_latch_status =     get_latch_status,
  60         .get_adapter_status =   get_adapter_status,
  61 };
  62
  63 static int init_slots(struct controller *ctrl)
  64 {
  65         struct slot *slot;
  66         struct hotplug_slot *hotplug_slot;
  67         char name[SLOT_NAME_SIZE];
  68         int retval;
  69         int i;
  70
  71         for (i = 0; i < ctrl->num_slots; i++) {
  72                 slot = kzalloc(sizeof(*slot), GFP_KERNEL);
  73                 if (!slot) {
  74                         retval = -ENOMEM;
  75                         goto error;
  76                 }
  77
  78                 hotplug_slot = &slot->hotplug_slot;
  79
  80                 slot->hp_slot = i;
  81                 slot->ctrl = ctrl;
  82                 slot->bus = ctrl->pci_dev->subordinate->number;
  83                 slot->device = ctrl->slot_device_offset + i;
  84                 slot->number = ctrl->first_slot + (ctrl->slot_num_inc * i);
  85
  86                 slot->wq = alloc_workqueue("shpchp-%d", 0, 0, slot->number);
  87                 if (!slot->wq) {
  88                         retval = -ENOMEM;
  89                         goto error_slot;
  90                 }
  91
  92                 mutex_init(&slot->lock);
  93                 INIT_DELAYED_WORK(&slot->work, shpchp_queue_pushbutton_work);
  94
  95                 /* register this slot with the hotplug pci core */
  96                 snprintf(name, SLOT_NAME_SIZE, "%d", slot->number);
  97                 hotplug_slot->ops = &shpchp_hotplug_slot_ops;
  98
  99                 ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x hp_slot=%x sun=%x slot_device_offset=%x\n",
 100                          pci_domain_nr(ctrl->pci_dev->subordinate),
 101                          slot->bus, slot->device, slot->hp_slot, slot->number,
 102                          ctrl->slot_device_offset);
 103                 retval = pci_hp_register(hotplug_slot,
 104                                 ctrl->pci_dev->subordinate, slot->device, name);
 105                 if (retval) {
 106                         ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
 107                                  retval);
 108                         goto error_slotwq;
 109                 }
 110
 111                 get_power_status(hotplug_slot, &slot->pwr_save);
 112                 get_attention_status(hotplug_slot, &slot->attention_save);
 113                 get_latch_status(hotplug_slot, &slot->latch_save);
 114                 get_adapter_status(hotplug_slot, &slot->presence_save);
 115
 116                 list_add(&slot->slot_list, &ctrl->slot_list);
 117         }
 118
 119         return 0;
 120 error_slotwq:
 121         destroy_workqueue(slot->wq);
 122 error_slot:
 123         kfree(slot);
 124 error:
 125         return retval;
 126 }
 127
 128 void cleanup_slots(struct controller *ctrl)
 129 {
 130         struct slot *slot, *next;
 131
 132         list_for_each_entry_safe(slot, next, &ctrl->slot_list, slot_list) {
 133                 list_del(&slot->slot_list);
 134                 cancel_delayed_work(&slot->work);
 135                 destroy_workqueue(slot->wq);
 136                 pci_hp_deregister(&slot->hotplug_slot);
 137                 kfree(slot);
 138         }
 139 }
 140
 141 /*
 142  * set_attention_status - Turns the Amber LED for a slot on, off or blink
 143  */
 144 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
 145 {
 146         struct slot *slot = get_slot(hotplug_slot);
 147
 148         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 149                  __func__, slot_name(slot));
 150
 151         slot->attention_save = status;
 152         shpchp_set_attention_status(slot, status);
 153
 154         return 0;
 155 }
 156
 157 static int enable_slot(struct hotplug_slot *hotplug_slot)
 158 {
 159         struct slot *slot = get_slot(hotplug_slot);
 160
 161         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 162                  __func__, slot_name(slot));
 163
 164         return shpchp_sysfs_enable_slot(slot);
 165 }
 166
 167 static int disable_slot(struct hotplug_slot *hotplug_slot)
 168 {
 169         struct slot *slot = get_slot(hotplug_slot);
 170
 171         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 172                  __func__, slot_name(slot));
 173
 174         return shpchp_sysfs_disable_slot(slot);
 175 }
 176
 177 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
 178 {
 179         struct slot *slot = get_slot(hotplug_slot);
 180         int retval;
 181
 182         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 183                  __func__, slot_name(slot));
 184
 185         retval = shpchp_get_power_status(slot, value);
 186         if (retval < 0)
 187                 *value = slot->pwr_save;
 188
 189         return 0;
 190 }
 191
 192 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
 193 {
 194         struct slot *slot = get_slot(hotplug_slot);
 195         int retval;
 196
 197         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 198                  __func__, slot_name(slot));
 199
 200         retval = shpchp_get_attention_status(slot, value);
 201         if (retval < 0)
 202                 *value = slot->attention_save;
 203
 204         return 0;
 205 }
 206
 207 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
 208 {
 209         struct slot *slot = get_slot(hotplug_slot);
 210         int retval;
 211
 212         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 213                  __func__, slot_name(slot));
 214
 215         retval = shpchp_get_latch_status(slot, value);
 216         if (retval < 0)
 217                 *value = slot->latch_save;
 218
 219         return 0;
 220 }
 221
 222 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
 223 {
 224         struct slot *slot = get_slot(hotplug_slot);
 225         int retval;
 226
 227         ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
 228                  __func__, slot_name(slot));
 229
 230         retval = shpchp_get_adapter_status(slot, value);
 231         if (retval < 0)
 232                 *value = slot->presence_save;
 233
 234         return 0;
 235 }
 236
 237 static bool shpc_capable(struct pci_dev *bridge)
 238 {
 239         /*
 240          * It is assumed that AMD GOLAM chips support SHPC but they do not
 241          * have SHPC capability.
 242          */
 243         if (bridge->vendor == PCI_VENDOR_ID_AMD &&
 244             bridge->device == PCI_DEVICE_ID_AMD_GOLAM_7450)
 245                 return true;
 246
 247         if (pci_find_capability(bridge, PCI_CAP_ID_SHPC))
 248                 return true;
 249
 250         return false;
 251 }
 252
 253 static int shpc_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 254 {
 255         int rc;
 256         struct controller *ctrl;
 257
 258         if (!shpc_capable(pdev))
 259                 return -ENODEV;
 260
 261         if (acpi_get_hp_hw_control_from_firmware(pdev))
 262                 return -ENODEV;
 263
 264         ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 265         if (!ctrl)
 266                 goto err_out_none;
 267
 268         INIT_LIST_HEAD(&ctrl->slot_list);
 269
 270         rc = shpc_init(ctrl, pdev);
 271         if (rc) {
 272                 ctrl_dbg(ctrl, "Controller initialization failed\n");
 273                 goto err_out_free_ctrl;
 274         }
 275
 276         pci_set_drvdata(pdev, ctrl);
 277
 278         /* Setup the slot information structures */
 279         rc = init_slots(ctrl);
 280         if (rc) {
 281                 ctrl_err(ctrl, "Slot initialization failed\n");
 282                 goto err_out_release_ctlr;
 283         }
 284
 285         rc = shpchp_create_ctrl_files(ctrl);
 286         if (rc)
 287                 goto err_cleanup_slots;
 288
 289         pdev->shpc_managed = 1;
 290         return 0;
 291
 292 err_cleanup_slots:
 293         cleanup_slots(ctrl);
 294 err_out_release_ctlr:
 295         shpchp_release_ctlr(ctrl);
 296 err_out_free_ctrl:
 297         kfree(ctrl);
 298 err_out_none:
 299         return -ENODEV;
 300 }
 301
 302 static void shpc_remove(struct pci_dev *dev)
 303 {
 304         struct controller *ctrl = pci_get_drvdata(dev);
 305
 306         dev->shpc_managed = 0;
 307         shpchp_remove_ctrl_files(ctrl);
 308         shpchp_release_ctlr(ctrl);
 309         kfree(ctrl);
 310 }
 311
 312 static const struct pci_device_id shpcd_pci_tbl[] = {
 313         {PCI_DEVICE_CLASS(PCI_CLASS_BRIDGE_PCI_NORMAL, ~0)},
 314         { /* end: all zeroes */ }
 315 };
 316 MODULE_DEVICE_TABLE(pci, shpcd_pci_tbl);
 317
 318 static struct pci_driver shpc_driver = {
 319         .name =         SHPC_MODULE_NAME,
 320         .id_table =     shpcd_pci_tbl,
 321         .probe =        shpc_probe,
 322         .remove =       shpc_remove,
 323 };
 324
 325 static int __init shpcd_init(void)
 326 {
 327         int retval;
 328
 329         retval = pci_register_driver(&shpc_driver);
 330         dbg("%s: pci_register_driver = %d\n", __func__, retval);
 331         info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
 332
 333         return retval;
 334 }
 335
 336 static void __exit shpcd_cleanup(void)
 337 {
 338         dbg("unload_shpchpd()\n");
 339         pci_unregister_driver(&shpc_driver);
 340         info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 341 }
 342
 343 module_init(shpcd_init);
 344 module_exit(shpcd_cleanup);