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