diff options
Diffstat (limited to 'drivers/acpi/bay.c')
| -rw-r--r-- | drivers/acpi/bay.c | 506 |
1 files changed, 506 insertions, 0 deletions
diff --git a/drivers/acpi/bay.c b/drivers/acpi/bay.c new file mode 100644 index 00000000000..aa1b131c0fc --- /dev/null +++ b/drivers/acpi/bay.c @@ -0,0 +1,506 @@ +/* + * 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> + +#define ACPI_BAY_DRIVER_NAME "ACPI Removable Drive Bay Driver" + +ACPI_MODULE_NAME("bay") +MODULE_AUTHOR("Kristen Carlson Accardi"); +MODULE_DESCRIPTION(ACPI_BAY_DRIVER_NAME); +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 int acpi_bay_add(struct acpi_device *device); +static int acpi_bay_remove(struct acpi_device *device, int type); +static int acpi_bay_match(struct acpi_device *device, + struct acpi_driver *driver); + +static struct acpi_driver acpi_bay_driver = { + .name = ACPI_BAY_DRIVER_NAME, + .class = ACPI_BAY_CLASS, + .ops = { + .add = acpi_bay_add, + .remove = acpi_bay_remove, + .match = acpi_bay_match, + }, +}; + +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)); + +} +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; +} +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(struct acpi_device *device) +{ + bay_dprintk(device->handle, "adding bay device"); + strcpy(acpi_device_name(device), "Dockable Bay"); + strcpy(acpi_device_class(device), "bay"); + return 0; +} + +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(GFP_ATOMIC, sizeof(*new_bay)); + 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 (pdev == NULL) { + printk(KERN_ERR PREFIX "Error registering bay device\n"); + goto bay_add_err; + } + new_bay->pdev = pdev; + platform_set_drvdata(pdev, new_bay); + + 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; +} + +static int acpi_bay_remove(struct acpi_device *device, int type) +{ + /*** FIXME: do something here */ + return 0; +} + +static int acpi_bay_match(struct acpi_device *device, + struct acpi_driver *driver) +{ + if (!device || !driver) + return -EINVAL; + + if (is_ejectable_bay(device->handle)) { + bay_dprintk(device->handle, "matching bay device"); + return 0; + } + + return -ENODEV; +} + +/** + * bay_create_acpi_device - add new devices to acpi + * @handle - handle of the device to add + * + * This function will create a new acpi_device for the given + * handle if one does not exist already. This should cause + * acpi to scan for drivers for the given devices, and call + * matching driver's add routine. + * + * Returns a pointer to the acpi_device corresponding to the handle. + */ +static struct acpi_device * bay_create_acpi_device(acpi_handle handle) +{ + struct acpi_device *device = NULL; + struct acpi_device *parent_device; + acpi_handle parent; + int ret; + + bay_dprintk(handle, "Trying to get device"); + if (acpi_bus_get_device(handle, &device)) { + /* + * no device created for this object, + * so we should create one. + */ + bay_dprintk(handle, "No device for handle"); + acpi_get_parent(handle, &parent); + if (acpi_bus_get_device(parent, &parent_device)) + parent_device = NULL; + + ret = acpi_bus_add(&device, parent_device, handle, + ACPI_BUS_TYPE_DEVICE); + if (ret) { + pr_debug("error adding bus, %x\n", + -ret); + return NULL; + } + } + return device; +} + +/** + * 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 acpi_device *dev; + + bay_dprintk(handle, "Bay event"); + + switch(event) { + case ACPI_NOTIFY_BUS_CHECK: + printk("Bus Check\n"); + case ACPI_NOTIFY_DEVICE_CHECK: + printk("Device Check\n"); + dev = bay_create_acpi_device(handle); + if (dev) + acpi_bus_generate_event(dev, event, 0); + else + printk("No device for generating event\n"); + /* wouldn't it be a good idea to just rescan SATA + * right here? + */ + break; + case ACPI_NOTIFY_EJECT_REQUEST: + printk("Eject request\n"); + dev = bay_create_acpi_device(handle); + if (dev) + acpi_bus_generate_event(dev, event, 0); + else + printk("No device for generating eventn"); + + /* wouldn't it be a good idea to just call the + * eject_device here if we were a SATA device? + */ + break; + default: + printk("unknown event %d\n", event); + } +} + +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) + if ((acpi_bus_register_driver(&acpi_bay_driver) < 0)) + printk(KERN_ERR "Unable to register bay driver\n"); + + 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); + } + + acpi_bus_unregister_driver(&acpi_bay_driver); +} + +postcore_initcall(bay_init); +module_exit(bay_exit); + |