/* * bay.c - ACPI removable drive bay driver * * Copyright (C) 2006 Kristen Carlson Accardi <kristen.c.accardi@intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/types.h> #include <linux/notifier.h> #include <acpi/acpi_bus.h> #include <acpi/acpi_drivers.h> #include <linux/seq_file.h> #include <asm/uaccess.h> #include <linux/platform_device.h> ACPI_MODULE_NAME("bay"); MODULE_AUTHOR("Kristen Carlson Accardi"); MODULE_DESCRIPTION("ACPI Removable Drive Bay Driver"); MODULE_LICENSE("GPL"); #define ACPI_BAY_CLASS "bay" #define ACPI_BAY_COMPONENT 0x10000000 #define _COMPONENT ACPI_BAY_COMPONENT #define bay_dprintk(h,s) {\ char prefix[80] = {'\0'};\ struct acpi_buffer buffer = {sizeof(prefix), prefix};\ acpi_get_name(h, ACPI_FULL_PATHNAME, &buffer);\ printk(KERN_DEBUG PREFIX "%s: %s\n", prefix, s); } static void bay_notify(acpi_handle handle, u32 event, void *data); static const struct acpi_device_id bay_device_ids[] = { {"LNXIOBAY", 0}, {"", 0}, }; MODULE_DEVICE_TABLE(acpi, bay_device_ids); struct bay { acpi_handle handle; char *name; struct list_head list; struct platform_device *pdev; }; static LIST_HEAD(drive_bays); /***************************************************************************** * Drive Bay functions * *****************************************************************************/ /** * is_ejectable - see if a device is ejectable * @handle: acpi handle of the device * * If an acpi object has a _EJ0 method, then it is ejectable */ static int is_ejectable(acpi_handle handle) { acpi_status status; acpi_handle tmp; status = acpi_get_handle(handle, "_EJ0", &tmp); if (ACPI_FAILURE(status)) return 0; return 1; } /** * bay_present - see if the bay device is present * @bay: the drive bay * * execute the _STA method. */ static int bay_present(struct bay *bay) { unsigned long sta; acpi_status status; if (bay) { status = acpi_evaluate_integer(bay->handle, "_STA", NULL, &sta); if (ACPI_SUCCESS(status) && sta) return 1; } return 0; } /** * eject_device - respond to an eject request * @handle - the device to eject * * Call this devices _EJ0 method. */ static void eject_device(acpi_handle handle) { struct acpi_object_list arg_list; union acpi_object arg; bay_dprintk(handle, "Ejecting device"); arg_list.count = 1; arg_list.pointer = &arg; arg.type = ACPI_TYPE_INTEGER; arg.integer.value = 1; if (ACPI_FAILURE(acpi_evaluate_object(handle, "_EJ0", &arg_list, NULL))) pr_debug("Failed to evaluate _EJ0!\n"); } /* * show_present - read method for "present" file in sysfs */ static ssize_t show_present(struct device *dev, struct device_attribute *attr, char *buf) { struct bay *bay = dev_get_drvdata(dev); return snprintf(buf, PAGE_SIZE, "%d\n", bay_present(bay)); } static DEVICE_ATTR(present, S_IRUGO, show_present, NULL); /* * write_eject - write method for "eject" file in sysfs */ static ssize_t write_eject(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { struct bay *bay = dev_get_drvdata(dev); if (!count) return -EINVAL; eject_device(bay->handle); return count; } static DEVICE_ATTR(eject, S_IWUSR, NULL, write_eject); /** * is_ata - see if a device is an ata device * @handle: acpi handle of the device * * If an acpi object has one of 4 ATA ACPI methods defined, * then it is an ATA device */ static int is_ata(acpi_handle handle) { acpi_handle tmp; if ((ACPI_SUCCESS(acpi_get_handle(handle, "_GTF", &tmp))) || (ACPI_SUCCESS(acpi_get_handle(handle, "_GTM", &tmp))) || (ACPI_SUCCESS(acpi_get_handle(handle, "_STM", &tmp))) || (ACPI_SUCCESS(acpi_get_handle(handle, "_SDD", &tmp)))) return 1; return 0; } /** * parent_is_ata(acpi_handle handle) * */ static int parent_is_ata(acpi_handle handle) { acpi_handle phandle; if (acpi_get_parent(handle, &phandle)) return 0; return is_ata(phandle); } /** * is_ejectable_bay - see if a device is an ejectable drive bay * @handle: acpi handle of the device * * If an acpi object is ejectable and has one of the ACPI ATA * methods defined, then we can safely call it an ejectable * drive bay */ static int is_ejectable_bay(acpi_handle handle) { if ((is_ata(handle) || parent_is_ata(handle)) && is_ejectable(handle)) return 1; return 0; } /** * eject_removable_drive - try to eject this drive * @dev : the device structure of the drive * * If a device is a removable drive that requires an _EJ0 method * to be executed in order to safely remove from the system, do * it. ATM - always returns success */ int eject_removable_drive(struct device *dev) { acpi_handle handle = DEVICE_ACPI_HANDLE(dev); if (handle) { bay_dprintk(handle, "Got device handle"); if (is_ejectable_bay(handle)) eject_device(handle); } else { printk("No acpi handle for device\n"); } /* should I return an error code? */ return 0; } EXPORT_SYMBOL_GPL(eject_removable_drive); static int acpi_bay_add_fs(struct bay *bay) { int ret; struct device *dev = &bay->pdev->dev; ret = device_create_file(dev, &dev_attr_present); if (ret) goto add_fs_err; ret = device_create_file(dev, &dev_attr_eject); if (ret) { device_remove_file(dev, &dev_attr_present); goto add_fs_err; } return 0; add_fs_err: bay_dprintk(bay->handle, "Error adding sysfs files\n"); return ret; } static void acpi_bay_remove_fs(struct bay *bay) { struct device *dev = &bay->pdev->dev; /* cleanup sysfs */ device_remove_file(dev, &dev_attr_present); device_remove_file(dev, &dev_attr_eject); } static int bay_is_dock_device(acpi_handle handle) { acpi_handle parent; acpi_get_parent(handle, &parent); /* if the device or it's parent is dependent on the * dock, then we are a dock device */ return (is_dock_device(handle) || is_dock_device(parent)); } static int bay_add(acpi_handle handle, int id) { acpi_status status; struct bay *new_bay; struct platform_device *pdev; struct acpi_buffer nbuffer = {ACPI_ALLOCATE_BUFFER, NULL}; acpi_get_name(handle, ACPI_FULL_PATHNAME, &nbuffer); bay_dprintk(handle, "Adding notify handler"); /* * Initialize bay device structure */ new_bay = kzalloc(sizeof(*new_bay), GFP_ATOMIC); INIT_LIST_HEAD(&new_bay->list); new_bay->handle = handle; new_bay->name = (char *)nbuffer.pointer; /* initialize platform device stuff */ pdev = platform_device_register_simple(ACPI_BAY_CLASS, id, NULL, 0); if (IS_ERR(pdev)) { printk(KERN_ERR PREFIX "Error registering bay device\n"); goto bay_add_err; } new_bay->pdev = pdev; platform_set_drvdata(pdev, new_bay); /* * we want the bay driver to be able to send uevents */ pdev->dev.uevent_suppress = 0; if (acpi_bay_add_fs(new_bay)) { platform_device_unregister(new_bay->pdev); goto bay_add_err; } /* register for events on this device */ status = acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY, bay_notify, new_bay); if (ACPI_FAILURE(status)) { printk(KERN_ERR PREFIX "Error installing bay notify handler\n"); } /* if we are on a dock station, we should register for dock * notifications. */ if (bay_is_dock_device(handle)) { bay_dprintk(handle, "Is dependent on dock\n"); register_hotplug_dock_device(handle, bay_notify, new_bay); } list_add(&new_bay->list, &drive_bays); printk(KERN_INFO PREFIX "Bay [%s] Added\n", new_bay->name); return 0; bay_add_err: kfree(new_bay->name); kfree(new_bay); return -ENODEV; } /** * bay_notify - act upon an acpi bay notification * @handle: the bay handle * @event: the acpi event * @data: our driver data struct * */ static void bay_notify(acpi_handle handle, u32 event, void *data) { struct bay *bay_dev = (struct bay *)data; struct device *dev = &bay_dev->pdev->dev; char event_string[12]; char *envp[] = { event_string, NULL }; bay_dprintk(handle, "Bay event"); sprintf(event_string, "BAY_EVENT=%d", event); kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp); } static acpi_status find_bay(acpi_handle handle, u32 lvl, void *context, void **rv) { int *count = (int *)context; /* * there could be more than one ejectable bay. * so, just return AE_OK always so that every object * will be checked. */ if (is_ejectable_bay(handle)) { bay_dprintk(handle, "found ejectable bay"); if (!bay_add(handle, *count)) (*count)++; } return AE_OK; } static int __init bay_init(void) { int bays = 0; INIT_LIST_HEAD(&drive_bays); /* look for dockable drive bays */ acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX, find_bay, &bays, NULL); if (!bays) return -ENODEV; return 0; } static void __exit bay_exit(void) { struct bay *bay, *tmp; list_for_each_entry_safe(bay, tmp, &drive_bays, list) { if (is_dock_device(bay->handle)) unregister_hotplug_dock_device(bay->handle); acpi_bay_remove_fs(bay); acpi_remove_notify_handler(bay->handle, ACPI_SYSTEM_NOTIFY, bay_notify); platform_device_unregister(bay->pdev); kfree(bay->name); kfree(bay); } } postcore_initcall(bay_init); module_exit(bay_exit);