1/* 2 * bay.c - ACPI removable drive bay driver 3 * 4 * Copyright (C) 2006 Kristen Carlson Accardi <kristen.c.accardi@intel.com> 5 * 6 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 7 * 8 * This program is free software; you can redistribute it and/or modify 9 * it under the terms of the GNU General Public License as published by 10 * the Free Software Foundation; either version 2 of the License, or (at 11 * your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License along 19 * with this program; if not, write to the Free Software Foundation, Inc., 20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 21 * 22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 23 */ 24#include <linux/kernel.h> 25#include <linux/module.h> 26#include <linux/init.h> 27#include <linux/types.h> 28#include <linux/notifier.h> 29#include <acpi/acpi_bus.h> 30#include <acpi/acpi_drivers.h> 31#include <linux/seq_file.h> 32#include <asm/uaccess.h> 33#include <linux/platform_device.h> 34 35ACPI_MODULE_NAME("bay"); 36MODULE_AUTHOR("Kristen Carlson Accardi"); 37MODULE_DESCRIPTION("ACPI Removable Drive Bay Driver"); 38MODULE_LICENSE("GPL"); 39#define ACPI_BAY_CLASS "bay" 40#define ACPI_BAY_COMPONENT 0x10000000 41#define _COMPONENT ACPI_BAY_COMPONENT 42#define bay_dprintk(h,s) {\ 43 char prefix[80] = {'\0'};\ 44 struct acpi_buffer buffer = {sizeof(prefix), prefix};\ 45 acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);\ 46 printk(KERN_DEBUG PREFIX "%s: %s\n", prefix, s); } 47static void bay_notify(acpi_handle handle, u32 event, void *data); 48 49struct bay { 50 acpi_handle handle; 51 char *name; 52 struct list_head list; 53 struct platform_device *pdev; 54}; 55 56static LIST_HEAD(drive_bays); 57 58 59/***************************************************************************** 60 * Drive Bay functions * 61 *****************************************************************************/ 62/** 63 * is_ejectable - see if a device is ejectable 64 * @handle: acpi handle of the device 65 * 66 * If an acpi object has a _EJ0 method, then it is ejectable 67 */ 68static int is_ejectable(acpi_handle handle) 69{ 70 acpi_status status; 71 acpi_handle tmp; 72 73 status = acpi_get_handle(handle, "_EJ0", &tmp); 74 if (ACPI_FAILURE(status)) 75 return 0; 76 return 1; 77} 78 79/** 80 * bay_present - see if the bay device is present 81 * @bay: the drive bay 82 * 83 * execute the _STA method. 84 */ 85static int bay_present(struct bay *bay) 86{ 87 unsigned long sta; 88 acpi_status status; 89 90 if (bay) { 91 status = acpi_evaluate_integer(bay->handle, "_STA", NULL, &sta); 92 if (ACPI_SUCCESS(status) && sta) 93 return 1; 94 } 95 return 0; 96} 97 98/** 99 * eject_device - respond to an eject request 100 * @handle - the device to eject 101 * 102 * Call this devices _EJ0 method. 103 */ 104static void eject_device(acpi_handle handle) 105{ 106 struct acpi_object_list arg_list; 107 union acpi_object arg; 108 109 bay_dprintk(handle, "Ejecting device"); 110 111 arg_list.count = 1; 112 arg_list.pointer = &arg; 113 arg.type = ACPI_TYPE_INTEGER; 114 arg.integer.value = 1; 115 116 if (ACPI_FAILURE(acpi_evaluate_object(handle, "_EJ0", 117 &arg_list, NULL))) 118 pr_debug("Failed to evaluate _EJ0!\n"); 119} 120 121/* 122 * show_present - read method for "present" file in sysfs 123 */ 124static ssize_t show_present(struct device *dev, 125 struct device_attribute *attr, char *buf) 126{ 127 struct bay *bay = dev_get_drvdata(dev); 128 return snprintf(buf, PAGE_SIZE, "%d\n", bay_present(bay)); 129 130} 131DEVICE_ATTR(present, S_IRUGO, show_present, NULL); 132 133/* 134 * write_eject - write method for "eject" file in sysfs 135 */ 136static ssize_t write_eject(struct device *dev, struct device_attribute *attr, 137 const char *buf, size_t count) 138{ 139 struct bay *bay = dev_get_drvdata(dev); 140 141 if (!count) 142 return -EINVAL; 143 144 eject_device(bay->handle); 145 return count; 146} 147DEVICE_ATTR(eject, S_IWUSR, NULL, write_eject); 148 149/** 150 * is_ata - see if a device is an ata device 151 * @handle: acpi handle of the device 152 * 153 * If an acpi object has one of 4 ATA ACPI methods defined, 154 * then it is an ATA device 155 */ 156static int is_ata(acpi_handle handle) 157{ 158 acpi_handle tmp; 159 160 if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) || 161 (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) || 162 (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) || 163 (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp)))) 164 return 1; 165 166 return 0; 167} 168 169/** 170 * parent_is_ata(acpi_handle handle) 171 * 172 */ 173static int parent_is_ata(acpi_handle handle) 174{ 175 acpi_handle phandle; 176 177 if (acpi_get_parent(handle, &phandle)) 178 return 0; 179 180 return is_ata(phandle); 181} 182 183/** 184 * is_ejectable_bay - see if a device is an ejectable drive bay 185 * @handle: acpi handle of the device 186 * 187 * If an acpi object is ejectable and has one of the ACPI ATA 188 * methods defined, then we can safely call it an ejectable 189 * drive bay 190 */ 191static int is_ejectable_bay(acpi_handle handle) 192{ 193 if ((is_ata(handle) || parent_is_ata(handle)) && is_ejectable(handle)) 194 return 1; 195 return 0; 196} 197 198/** 199 * eject_removable_drive - try to eject this drive 200 * @dev : the device structure of the drive 201 * 202 * If a device is a removable drive that requires an _EJ0 method 203 * to be executed in order to safely remove from the system, do 204 * it. ATM - always returns success 205 */ 206int eject_removable_drive(struct device *dev) 207{ 208 acpi_handle handle = DEVICE_ACPI_HANDLE(dev); 209 210 if (handle) { 211 bay_dprintk(handle, "Got device handle"); 212 if (is_ejectable_bay(handle)) 213 eject_device(handle); 214 } else { 215 printk("No acpi handle for device\n"); 216 } 217 218 /* should I return an error code? */ 219 return 0; 220} 221EXPORT_SYMBOL_GPL(eject_removable_drive); 222 223static int acpi_bay_add_fs(struct bay *bay) 224{ 225 int ret; 226 struct device *dev = &bay->pdev->dev; 227 228 ret = device_create_file(dev, &dev_attr_present); 229 if (ret) 230 goto add_fs_err; 231 ret = device_create_file(dev, &dev_attr_eject); 232 if (ret) { 233 device_remove_file(dev, &dev_attr_present); 234 goto add_fs_err; 235 } 236 return 0; 237 238 add_fs_err: 239 bay_dprintk(bay->handle, "Error adding sysfs files\n"); 240 return ret; 241} 242 243static void acpi_bay_remove_fs(struct bay *bay) 244{ 245 struct device *dev = &bay->pdev->dev; 246 247 /* cleanup sysfs */ 248 device_remove_file(dev, &dev_attr_present); 249 device_remove_file(dev, &dev_attr_eject); 250} 251 252static int bay_is_dock_device(acpi_handle handle) 253{ 254 acpi_handle parent; 255 256 acpi_get_parent(handle, &parent); 257 258 /* if the device or it's parent is dependent on the 259 * dock, then we are a dock device 260 */ 261 return (is_dock_device(handle) || is_dock_device(parent)); 262} 263 264static int bay_add(acpi_handle handle, int id) 265{ 266 acpi_status status; 267 struct bay *new_bay; 268 struct platform_device *pdev; 269 struct acpi_buffer nbuffer = {ACPI_ALLOCATE_BUFFER, NULL}; 270 acpi_get_name(handle, ACPI_FULL_PATHNAME, &nbuffer); 271 272 bay_dprintk(handle, "Adding notify handler"); 273 274 /* 275 * Initialize bay device structure 276 */ 277 new_bay = kzalloc(sizeof(*new_bay), GFP_ATOMIC); 278 INIT_LIST_HEAD(&new_bay->list); 279 new_bay->handle = handle; 280 new_bay->name = (char *)nbuffer.pointer; 281 282 /* initialize platform device stuff */ 283 pdev = platform_device_register_simple(ACPI_BAY_CLASS, id, NULL, 0); 284 if (IS_ERR(pdev)) { 285 printk(KERN_ERR PREFIX "Error registering bay device\n"); 286 goto bay_add_err; 287 } 288 new_bay->pdev = pdev; 289 platform_set_drvdata(pdev, new_bay); 290 291 if (acpi_bay_add_fs(new_bay)) { 292 platform_device_unregister(new_bay->pdev); 293 goto bay_add_err; 294 } 295 296 /* register for events on this device */ 297 status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY, 298 bay_notify, new_bay); 299 if (ACPI_FAILURE(status)) { 300 printk(KERN_ERR PREFIX "Error installing bay notify handler\n"); 301 } 302 303 /* if we are on a dock station, we should register for dock 304 * notifications. 305 */ 306 if (bay_is_dock_device(handle)) { 307 bay_dprintk(handle, "Is dependent on dock\n"); 308 register_hotplug_dock_device(handle, bay_notify, new_bay); 309 } 310 list_add(&new_bay->list, &drive_bays); 311 printk(KERN_INFO PREFIX "Bay [%s] Added\n", new_bay->name); 312 return 0; 313 314bay_add_err: 315 kfree(new_bay->name); 316 kfree(new_bay); 317 return -ENODEV; 318} 319 320/** 321 * bay_notify - act upon an acpi bay notification 322 * @handle: the bay handle 323 * @event: the acpi event 324 * @data: our driver data struct 325 * 326 */ 327static void bay_notify(acpi_handle handle, u32 event, void *data) 328{ 329 struct bay *bay_dev = (struct bay *)data; 330 struct device *dev = &bay_dev->pdev->dev; 331 332 bay_dprintk(handle, "Bay event"); 333 334 switch(event) { 335 case ACPI_NOTIFY_BUS_CHECK: 336 case ACPI_NOTIFY_DEVICE_CHECK: 337 case ACPI_NOTIFY_EJECT_REQUEST: 338 kobject_uevent(&dev->kobj, KOBJ_CHANGE); 339 break; 340 default: 341 printk(KERN_ERR PREFIX "Bay: unknown event %d\n", event); 342 } 343} 344 345static acpi_status 346find_bay(acpi_handle handle, u32 lvl, void *context, void **rv) 347{ 348 int *count = (int *)context; 349 350 /* 351 * there could be more than one ejectable bay. 352 * so, just return AE_OK always so that every object 353 * will be checked. 354 */ 355 if (is_ejectable_bay(handle)) { 356 bay_dprintk(handle, "found ejectable bay"); 357 if (!bay_add(handle, *count)) 358 (*count)++; 359 } 360 return AE_OK; 361} 362 363static int __init bay_init(void) 364{ 365 int bays = 0; 366 367 INIT_LIST_HEAD(&drive_bays); 368 369 /* look for dockable drive bays */ 370 acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, 371 ACPI_UINT32_MAX, find_bay, &bays, NULL); 372 373 if (!bays) 374 return -ENODEV; 375 376 return 0; 377} 378 379static void __exit bay_exit(void) 380{ 381 struct bay *bay, *tmp; 382 383 list_for_each_entry_safe(bay, tmp, &drive_bays, list) { 384 if (is_dock_device(bay->handle)) 385 unregister_hotplug_dock_device(bay->handle); 386 acpi_bay_remove_fs(bay); 387 acpi_remove_notify_handler(bay->handle, ACPI_SYSTEM_NOTIFY, 388 bay_notify); 389 platform_device_unregister(bay->pdev); 390 kfree(bay->name); 391 kfree(bay); 392 } 393} 394 395postcore_initcall(bay_init); 396module_exit(bay_exit); 397