acpiphp_core.c (8480B)
1// SPDX-License-Identifier: GPL-2.0+ 2/* 3 * ACPI PCI 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) 2002 Hiroshi Aono (h-aono@ap.jp.nec.com) 9 * Copyright (C) 2002,2003 Takayoshi Kochi (t-kochi@bq.jp.nec.com) 10 * Copyright (C) 2002,2003 NEC Corporation 11 * Copyright (C) 2003-2005 Matthew Wilcox (willy@infradead.org) 12 * Copyright (C) 2003-2005 Hewlett Packard 13 * 14 * All rights reserved. 15 * 16 * Send feedback to <kristen.c.accardi@intel.com> 17 * 18 */ 19 20#define pr_fmt(fmt) "acpiphp: " fmt 21 22#include <linux/init.h> 23#include <linux/module.h> 24#include <linux/moduleparam.h> 25 26#include <linux/kernel.h> 27#include <linux/pci.h> 28#include <linux/pci-acpi.h> 29#include <linux/pci_hotplug.h> 30#include <linux/slab.h> 31#include <linux/smp.h> 32#include "acpiphp.h" 33 34/* name size which is used for entries in pcihpfs */ 35#define SLOT_NAME_SIZE 21 /* {_SUN} */ 36 37bool acpiphp_disabled; 38 39/* local variables */ 40static struct acpiphp_attention_info *attention_info; 41 42#define DRIVER_VERSION "0.5" 43#define DRIVER_AUTHOR "Greg Kroah-Hartman <gregkh@us.ibm.com>, Takayoshi Kochi <t-kochi@bq.jp.nec.com>, Matthew Wilcox <willy@infradead.org>" 44#define DRIVER_DESC "ACPI Hot Plug PCI Controller Driver" 45 46MODULE_AUTHOR(DRIVER_AUTHOR); 47MODULE_DESCRIPTION(DRIVER_DESC); 48MODULE_LICENSE("GPL"); 49MODULE_PARM_DESC(disable, "disable acpiphp driver"); 50module_param_named(disable, acpiphp_disabled, bool, 0444); 51 52static int enable_slot(struct hotplug_slot *slot); 53static int disable_slot(struct hotplug_slot *slot); 54static int set_attention_status(struct hotplug_slot *slot, u8 value); 55static int get_power_status(struct hotplug_slot *slot, u8 *value); 56static int get_attention_status(struct hotplug_slot *slot, u8 *value); 57static int get_latch_status(struct hotplug_slot *slot, u8 *value); 58static int get_adapter_status(struct hotplug_slot *slot, u8 *value); 59 60static const struct hotplug_slot_ops acpi_hotplug_slot_ops = { 61 .enable_slot = enable_slot, 62 .disable_slot = disable_slot, 63 .set_attention_status = set_attention_status, 64 .get_power_status = get_power_status, 65 .get_attention_status = get_attention_status, 66 .get_latch_status = get_latch_status, 67 .get_adapter_status = get_adapter_status, 68}; 69 70/** 71 * acpiphp_register_attention - set attention LED callback 72 * @info: must be completely filled with LED callbacks 73 * 74 * Description: This is used to register a hardware specific ACPI 75 * driver that manipulates the attention LED. All the fields in 76 * info must be set. 77 */ 78int acpiphp_register_attention(struct acpiphp_attention_info *info) 79{ 80 int retval = -EINVAL; 81 82 if (info && info->owner && info->set_attn && 83 info->get_attn && !attention_info) { 84 retval = 0; 85 attention_info = info; 86 } 87 return retval; 88} 89EXPORT_SYMBOL_GPL(acpiphp_register_attention); 90 91 92/** 93 * acpiphp_unregister_attention - unset attention LED callback 94 * @info: must match the pointer used to register 95 * 96 * Description: This is used to un-register a hardware specific acpi 97 * driver that manipulates the attention LED. The pointer to the 98 * info struct must be the same as the one used to set it. 99 */ 100int acpiphp_unregister_attention(struct acpiphp_attention_info *info) 101{ 102 int retval = -EINVAL; 103 104 if (info && attention_info == info) { 105 attention_info = NULL; 106 retval = 0; 107 } 108 return retval; 109} 110EXPORT_SYMBOL_GPL(acpiphp_unregister_attention); 111 112 113/** 114 * enable_slot - power on and enable a slot 115 * @hotplug_slot: slot to enable 116 * 117 * Actual tasks are done in acpiphp_enable_slot() 118 */ 119static int enable_slot(struct hotplug_slot *hotplug_slot) 120{ 121 struct slot *slot = to_slot(hotplug_slot); 122 123 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot)); 124 125 /* enable the specified slot */ 126 return acpiphp_enable_slot(slot->acpi_slot); 127} 128 129 130/** 131 * disable_slot - disable and power off a slot 132 * @hotplug_slot: slot to disable 133 * 134 * Actual tasks are done in acpiphp_disable_slot() 135 */ 136static int disable_slot(struct hotplug_slot *hotplug_slot) 137{ 138 struct slot *slot = to_slot(hotplug_slot); 139 140 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot)); 141 142 /* disable the specified slot */ 143 return acpiphp_disable_slot(slot->acpi_slot); 144} 145 146 147/** 148 * set_attention_status - set attention LED 149 * @hotplug_slot: slot to set attention LED on 150 * @status: value to set attention LED to (0 or 1) 151 * 152 * attention status LED, so we use a callback that 153 * was registered with us. This allows hardware specific 154 * ACPI implementations to blink the light for us. 155 */ 156static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status) 157{ 158 int retval = -ENODEV; 159 160 pr_debug("%s - physical_slot = %s\n", __func__, 161 hotplug_slot_name(hotplug_slot)); 162 163 if (attention_info && try_module_get(attention_info->owner)) { 164 retval = attention_info->set_attn(hotplug_slot, status); 165 module_put(attention_info->owner); 166 } else 167 attention_info = NULL; 168 return retval; 169} 170 171 172/** 173 * get_power_status - get power status of a slot 174 * @hotplug_slot: slot to get status 175 * @value: pointer to store status 176 * 177 * Some platforms may not implement _STA method properly. 178 * In that case, the value returned may not be reliable. 179 */ 180static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value) 181{ 182 struct slot *slot = to_slot(hotplug_slot); 183 184 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot)); 185 186 *value = acpiphp_get_power_status(slot->acpi_slot); 187 188 return 0; 189} 190 191 192/** 193 * get_attention_status - get attention LED status 194 * @hotplug_slot: slot to get status from 195 * @value: returns with value of attention LED 196 * 197 * ACPI doesn't have known method to determine the state 198 * of the attention status LED, so we use a callback that 199 * was registered with us. This allows hardware specific 200 * ACPI implementations to determine its state. 201 */ 202static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value) 203{ 204 int retval = -EINVAL; 205 206 pr_debug("%s - physical_slot = %s\n", __func__, 207 hotplug_slot_name(hotplug_slot)); 208 209 if (attention_info && try_module_get(attention_info->owner)) { 210 retval = attention_info->get_attn(hotplug_slot, value); 211 module_put(attention_info->owner); 212 } else 213 attention_info = NULL; 214 return retval; 215} 216 217 218/** 219 * get_latch_status - get latch status of a slot 220 * @hotplug_slot: slot to get status 221 * @value: pointer to store status 222 * 223 * ACPI doesn't provide any formal means to access latch status. 224 * Instead, we fake latch status from _STA. 225 */ 226static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value) 227{ 228 struct slot *slot = to_slot(hotplug_slot); 229 230 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot)); 231 232 *value = acpiphp_get_latch_status(slot->acpi_slot); 233 234 return 0; 235} 236 237 238/** 239 * get_adapter_status - get adapter status of a slot 240 * @hotplug_slot: slot to get status 241 * @value: pointer to store status 242 * 243 * ACPI doesn't provide any formal means to access adapter status. 244 * Instead, we fake adapter status from _STA. 245 */ 246static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value) 247{ 248 struct slot *slot = to_slot(hotplug_slot); 249 250 pr_debug("%s - physical_slot = %s\n", __func__, slot_name(slot)); 251 252 *value = acpiphp_get_adapter_status(slot->acpi_slot); 253 254 return 0; 255} 256 257/* callback routine to initialize 'struct slot' for each slot */ 258int acpiphp_register_hotplug_slot(struct acpiphp_slot *acpiphp_slot, 259 unsigned int sun) 260{ 261 struct slot *slot; 262 int retval = -ENOMEM; 263 char name[SLOT_NAME_SIZE]; 264 265 slot = kzalloc(sizeof(*slot), GFP_KERNEL); 266 if (!slot) 267 goto error; 268 269 slot->hotplug_slot.ops = &acpi_hotplug_slot_ops; 270 271 slot->acpi_slot = acpiphp_slot; 272 273 acpiphp_slot->slot = slot; 274 slot->sun = sun; 275 snprintf(name, SLOT_NAME_SIZE, "%u", sun); 276 277 retval = pci_hp_register(&slot->hotplug_slot, acpiphp_slot->bus, 278 acpiphp_slot->device, name); 279 if (retval == -EBUSY) 280 goto error_slot; 281 if (retval) { 282 pr_err("pci_hp_register failed with error %d\n", retval); 283 goto error_slot; 284 } 285 286 pr_info("Slot [%s] registered\n", slot_name(slot)); 287 288 return 0; 289error_slot: 290 kfree(slot); 291error: 292 return retval; 293} 294 295 296void acpiphp_unregister_hotplug_slot(struct acpiphp_slot *acpiphp_slot) 297{ 298 struct slot *slot = acpiphp_slot->slot; 299 300 pr_info("Slot [%s] unregistered\n", slot_name(slot)); 301 302 pci_hp_deregister(&slot->hotplug_slot); 303 kfree(slot); 304} 305 306 307void __init acpiphp_init(void) 308{ 309 pr_info(DRIVER_DESC " version: " DRIVER_VERSION "%s\n", 310 acpiphp_disabled ? ", disabled by user; please report a bug" 311 : ""); 312}