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