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