+++ /dev/null
-/*
- * dock.c - ACPI dock station 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>
-
-#define ACPI_DOCK_DRIVER_NAME "ACPI Dock Station Driver"
-
-ACPI_MODULE_NAME("dock")
-MODULE_AUTHOR("Kristen Carlson Accardi");
-MODULE_DESCRIPTION(ACPI_DOCK_DRIVER_NAME);
-MODULE_LICENSE("GPL");
-
-static struct atomic_notifier_head dock_notifier_list;
-
-struct dock_station {
- acpi_handle handle;
- unsigned long last_dock_time;
- u32 flags;
- spinlock_t dd_lock;
- spinlock_t hp_lock;
- struct list_head dependent_devices;
- struct list_head hotplug_devices;
-};
-
-struct dock_dependent_device {
- struct list_head list;
- struct list_head hotplug_list;
- acpi_handle handle;
- acpi_notify_handler handler;
- void *context;
-};
-
-#define DOCK_DOCKING 0x00000001
-#define DOCK_EVENT KOBJ_DOCK
-#define UNDOCK_EVENT KOBJ_UNDOCK
-
-static struct dock_station *dock_station;
-
-/*****************************************************************************
- * Dock Dependent device functions *
- *****************************************************************************/
-/**
- * alloc_dock_dependent_device - allocate and init a dependent device
- * @handle: the acpi_handle of the dependent device
- *
- * Allocate memory for a dependent device structure for a device referenced
- * by the acpi handle
- */
-static struct dock_dependent_device *
-alloc_dock_dependent_device(acpi_handle handle)
-{
- struct dock_dependent_device *dd;
-
- dd = kzalloc(sizeof(*dd), GFP_KERNEL);
- if (dd) {
- dd->handle = handle;
- INIT_LIST_HEAD(&dd->list);
- INIT_LIST_HEAD(&dd->hotplug_list);
- }
- return dd;
-}
-
-/**
- * add_dock_dependent_device - associate a device with the dock station
- * @ds: The dock station
- * @dd: The dependent device
- *
- * Add the dependent device to the dock's dependent device list.
- */
-static void
-add_dock_dependent_device(struct dock_station *ds,
- struct dock_dependent_device *dd)
-{
- spin_lock(&ds->dd_lock);
- list_add_tail(&dd->list, &ds->dependent_devices);
- spin_unlock(&ds->dd_lock);
-}
-
-/**
- * dock_add_hotplug_device - associate a hotplug handler with the dock station
- * @ds: The dock station
- * @dd: The dependent device struct
- *
- * Add the dependent device to the dock's hotplug device list
- */
-static void
-dock_add_hotplug_device(struct dock_station *ds,
- struct dock_dependent_device *dd)
-{
- spin_lock(&ds->hp_lock);
- list_add_tail(&dd->hotplug_list, &ds->hotplug_devices);
- spin_unlock(&ds->hp_lock);
-}
-
-/**
- * dock_del_hotplug_device - remove a hotplug handler from the dock station
- * @ds: The dock station
- * @dd: the dependent device struct
- *
- * Delete the dependent device from the dock's hotplug device list
- */
-static void
-dock_del_hotplug_device(struct dock_station *ds,
- struct dock_dependent_device *dd)
-{
- spin_lock(&ds->hp_lock);
- list_del(&dd->hotplug_list);
- spin_unlock(&ds->hp_lock);
-}
-
-/**
- * find_dock_dependent_device - get a device dependent on this dock
- * @ds: the dock station
- * @handle: the acpi_handle of the device we want
- *
- * iterate over the dependent device list for this dock. If the
- * dependent device matches the handle, return.
- */
-static struct dock_dependent_device *
-find_dock_dependent_device(struct dock_station *ds, acpi_handle handle)
-{
- struct dock_dependent_device *dd;
-
- spin_lock(&ds->dd_lock);
- list_for_each_entry(dd, &ds->dependent_devices, list) {
- if (handle == dd->handle) {
- spin_unlock(&ds->dd_lock);
- return dd;
- }
- }
- spin_unlock(&ds->dd_lock);
- return NULL;
-}
-
-/*****************************************************************************
- * Dock functions *
- *****************************************************************************/
-/**
- * is_dock - see if a device is a dock station
- * @handle: acpi handle of the device
- *
- * If an acpi object has a _DCK method, then it is by definition a dock
- * station, so return true.
- */
-static int is_dock(acpi_handle handle)
-{
- acpi_status status;
- acpi_handle tmp;
-
- status = acpi_get_handle(handle, "_DCK", &tmp);
- if (ACPI_FAILURE(status))
- return 0;
- return 1;
-}
-
-/**
- * is_dock_device - see if a device is on a dock station
- * @handle: acpi handle of the device
- *
- * If this device is either the dock station itself,
- * or is a device dependent on the dock station, then it
- * is a dock device
- */
-int is_dock_device(acpi_handle handle)
-{
- if (!dock_station)
- return 0;
-
- if (is_dock(handle) || find_dock_dependent_device(dock_station, handle))
- return 1;
-
- return 0;
-}
-
-EXPORT_SYMBOL_GPL(is_dock_device);
-
-/**
- * dock_present - see if the dock station is present.
- * @ds: the dock station
- *
- * execute the _STA method. note that present does not
- * imply that we are docked.
- */
-static int dock_present(struct dock_station *ds)
-{
- unsigned long sta;
- acpi_status status;
-
- if (ds) {
- status = acpi_evaluate_integer(ds->handle, "_STA", NULL, &sta);
- if (ACPI_SUCCESS(status) && sta)
- return 1;
- }
- return 0;
-}
-
-
-
-/**
- * dock_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 * dock_create_acpi_device(acpi_handle handle)
-{
- struct acpi_device *device = NULL;
- struct acpi_device *parent_device;
- acpi_handle parent;
- int ret;
-
- if (acpi_bus_get_device(handle, &device)) {
- /*
- * no device created for this object,
- * so we should create one.
- */
- 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;
-}
-
-/**
- * dock_remove_acpi_device - remove the acpi_device struct from acpi
- * @handle - the handle of the device to remove
- *
- * Tell acpi to remove the acpi_device. This should cause any loaded
- * driver to have it's remove routine called.
- */
-static void dock_remove_acpi_device(acpi_handle handle)
-{
- struct acpi_device *device;
- int ret;
-
- if (!acpi_bus_get_device(handle, &device)) {
- ret = acpi_bus_trim(device, 1);
- if (ret)
- pr_debug("error removing bus, %x\n", -ret);
- }
-}
-
-
-/**
- * hotplug_dock_devices - insert or remove devices on the dock station
- * @ds: the dock station
- * @event: either bus check or eject request
- *
- * Some devices on the dock station need to have drivers called
- * to perform hotplug operations after a dock event has occurred.
- * Traverse the list of dock devices that have registered a
- * hotplug handler, and call the handler.
- */
-static void hotplug_dock_devices(struct dock_station *ds, u32 event)
-{
- struct dock_dependent_device *dd;
-
- spin_lock(&ds->hp_lock);
-
- /*
- * First call driver specific hotplug functions
- */
- list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list) {
- if (dd->handler)
- dd->handler(dd->handle, event, dd->context);
- }
-
- /*
- * Now make sure that an acpi_device is created for each
- * dependent device, or removed if this is an eject request.
- * This will cause acpi_drivers to be stopped/started if they
- * exist
- */
- list_for_each_entry(dd, &ds->dependent_devices, list) {
- if (event == ACPI_NOTIFY_EJECT_REQUEST)
- dock_remove_acpi_device(dd->handle);
- else
- dock_create_acpi_device(dd->handle);
- }
- spin_unlock(&ds->hp_lock);
-}
-
-static void dock_event(struct dock_station *ds, u32 event, int num)
-{
- struct acpi_device *device;
-
- device = dock_create_acpi_device(ds->handle);
- if (device)
- kobject_uevent(&device->kobj, num);
-}
-
-/**
- * eject_dock - respond to a dock eject request
- * @ds: the dock station
- *
- * This is called after _DCK is called, to execute the dock station's
- * _EJ0 method.
- */
-static void eject_dock(struct dock_station *ds)
-{
- struct acpi_object_list arg_list;
- union acpi_object arg;
- acpi_status status;
- acpi_handle tmp;
-
- /* all dock devices should have _EJ0, but check anyway */
- status = acpi_get_handle(ds->handle, "_EJ0", &tmp);
- if (ACPI_FAILURE(status)) {
- pr_debug("No _EJ0 support for dock device\n");
- return;
- }
-
- arg_list.count = 1;
- arg_list.pointer = &arg;
- arg.type = ACPI_TYPE_INTEGER;
- arg.integer.value = 1;
-
- if (ACPI_FAILURE(acpi_evaluate_object(ds->handle, "_EJ0",
- &arg_list, NULL)))
- pr_debug("Failed to evaluate _EJ0!\n");
-}
-
-/**
- * handle_dock - handle a dock event
- * @ds: the dock station
- * @dock: to dock, or undock - that is the question
- *
- * Execute the _DCK method in response to an acpi event
- */
-static void handle_dock(struct dock_station *ds, int dock)
-{
- acpi_status status;
- struct acpi_object_list arg_list;
- union acpi_object arg;
- struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
- struct acpi_buffer name_buffer = { ACPI_ALLOCATE_BUFFER, NULL };
- union acpi_object *obj;
-
- acpi_get_name(ds->handle, ACPI_FULL_PATHNAME, &name_buffer);
- obj = name_buffer.pointer;
-
- printk(KERN_INFO PREFIX "%s\n", dock ? "docking" : "undocking");
-
- /* _DCK method has one argument */
- arg_list.count = 1;
- arg_list.pointer = &arg;
- arg.type = ACPI_TYPE_INTEGER;
- arg.integer.value = dock;
- status = acpi_evaluate_object(ds->handle, "_DCK", &arg_list, &buffer);
- if (ACPI_FAILURE(status))
- pr_debug("%s: failed to execute _DCK\n", obj->string.pointer);
- kfree(buffer.pointer);
- kfree(name_buffer.pointer);
-}
-
-static inline void dock(struct dock_station *ds)
-{
- handle_dock(ds, 1);
-}
-
-static inline void undock(struct dock_station *ds)
-{
- handle_dock(ds, 0);
-}
-
-static inline void begin_dock(struct dock_station *ds)
-{
- ds->flags |= DOCK_DOCKING;
-}
-
-static inline void complete_dock(struct dock_station *ds)
-{
- ds->flags &= ~(DOCK_DOCKING);
- ds->last_dock_time = jiffies;
-}
-
-/**
- * dock_in_progress - see if we are in the middle of handling a dock event
- * @ds: the dock station
- *
- * Sometimes while docking, false dock events can be sent to the driver
- * because good connections aren't made or some other reason. Ignore these
- * if we are in the middle of doing something.
- */
-static int dock_in_progress(struct dock_station *ds)
-{
- if ((ds->flags & DOCK_DOCKING) ||
- time_before(jiffies, (ds->last_dock_time + HZ)))
- return 1;
- return 0;
-}
-
-/**
- * register_dock_notifier - add yourself to the dock notifier list
- * @nb: the callers notifier block
- *
- * If a driver wishes to be notified about dock events, they can
- * use this function to put a notifier block on the dock notifier list.
- * this notifier call chain will be called after a dock event, but
- * before hotplugging any new devices.
- */
-int register_dock_notifier(struct notifier_block *nb)
-{
- return atomic_notifier_chain_register(&dock_notifier_list, nb);
-}
-
-EXPORT_SYMBOL_GPL(register_dock_notifier);
-
-/**
- * unregister_dock_notifier - remove yourself from the dock notifier list
- * @nb: the callers notifier block
- */
-void unregister_dock_notifier(struct notifier_block *nb)
-{
- atomic_notifier_chain_unregister(&dock_notifier_list, nb);
-}
-
-EXPORT_SYMBOL_GPL(unregister_dock_notifier);
-
-/**
- * register_hotplug_dock_device - register a hotplug function
- * @handle: the handle of the device
- * @handler: the acpi_notifier_handler to call after docking
- * @context: device specific data
- *
- * If a driver would like to perform a hotplug operation after a dock
- * event, they can register an acpi_notifiy_handler to be called by
- * the dock driver after _DCK is executed.
- */
-int
-register_hotplug_dock_device(acpi_handle handle, acpi_notify_handler handler,
- void *context)
-{
- struct dock_dependent_device *dd;
-
- if (!dock_station)
- return -ENODEV;
-
- /*
- * make sure this handle is for a device dependent on the dock,
- * this would include the dock station itself
- */
- dd = find_dock_dependent_device(dock_station, handle);
- if (dd) {
- dd->handler = handler;
- dd->context = context;
- dock_add_hotplug_device(dock_station, dd);
- return 0;
- }
-
- return -EINVAL;
-}
-
-EXPORT_SYMBOL_GPL(register_hotplug_dock_device);
-
-/**
- * unregister_hotplug_dock_device - remove yourself from the hotplug list
- * @handle: the acpi handle of the device
- */
-void unregister_hotplug_dock_device(acpi_handle handle)
-{
- struct dock_dependent_device *dd;
-
- if (!dock_station)
- return;
-
- dd = find_dock_dependent_device(dock_station, handle);
- if (dd)
- dock_del_hotplug_device(dock_station, dd);
-}
-
-EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
-
-/**
- * dock_notify - act upon an acpi dock notification
- * @handle: the dock station handle
- * @event: the acpi event
- * @data: our driver data struct
- *
- * If we are notified to dock, then check to see if the dock is
- * present and then dock. Notify all drivers of the dock event,
- * and then hotplug and devices that may need hotplugging. For undock
- * check to make sure the dock device is still present, then undock
- * and hotremove all the devices that may need removing.
- */
-static void dock_notify(acpi_handle handle, u32 event, void *data)
-{
- struct dock_station *ds = (struct dock_station *)data;
-
- switch (event) {
- case ACPI_NOTIFY_BUS_CHECK:
- if (!dock_in_progress(ds) && dock_present(ds)) {
- begin_dock(ds);
- dock(ds);
- if (!dock_present(ds)) {
- printk(KERN_ERR PREFIX "Unable to dock!\n");
- break;
- }
- atomic_notifier_call_chain(&dock_notifier_list,
- event, NULL);
- hotplug_dock_devices(ds, event);
- complete_dock(ds);
- dock_event(ds, event, DOCK_EVENT);
- }
- break;
- case ACPI_NOTIFY_DEVICE_CHECK:
- /*
- * According to acpi spec 3.0a, if a DEVICE_CHECK notification
- * is sent and _DCK is present, it is assumed to mean an
- * undock request. This notify routine will only be called
- * for objects defining _DCK, so we will fall through to eject
- * request here. However, we will pass an eject request through
- * to the driver who wish to hotplug.
- */
- case ACPI_NOTIFY_EJECT_REQUEST:
- if (!dock_in_progress(ds) && dock_present(ds)) {
- /*
- * here we need to generate the undock
- * event prior to actually doing the undock
- * so that the device struct still exists.
- */
- dock_event(ds, event, UNDOCK_EVENT);
- hotplug_dock_devices(ds, ACPI_NOTIFY_EJECT_REQUEST);
- undock(ds);
- eject_dock(ds);
- if (dock_present(ds))
- printk(KERN_ERR PREFIX "Unable to undock!\n");
- }
- break;
- default:
- printk(KERN_ERR PREFIX "Unknown dock event %d\n", event);
- }
-}
-
-/**
- * find_dock_devices - find devices on the dock station
- * @handle: the handle of the device we are examining
- * @lvl: unused
- * @context: the dock station private data
- * @rv: unused
- *
- * This function is called by acpi_walk_namespace. It will
- * check to see if an object has an _EJD method. If it does, then it
- * will see if it is dependent on the dock station.
- */
-static acpi_status
-find_dock_devices(acpi_handle handle, u32 lvl, void *context, void **rv)
-{
- acpi_status status;
- acpi_handle tmp;
- struct dock_station *ds = (struct dock_station *)context;
- struct dock_dependent_device *dd;
-
- status = acpi_bus_get_ejd(handle, &tmp);
- if (ACPI_FAILURE(status))
- return AE_OK;
-
- if (tmp == ds->handle) {
- dd = alloc_dock_dependent_device(handle);
- if (dd)
- add_dock_dependent_device(ds, dd);
- }
-
- return AE_OK;
-}
-
-/**
- * dock_add - add a new dock station
- * @handle: the dock station handle
- *
- * allocated and initialize a new dock station device. Find all devices
- * that are on the dock station, and register for dock event notifications.
- */
-static int dock_add(acpi_handle handle)
-{
- int ret;
- acpi_status status;
- struct dock_dependent_device *dd;
-
- /* allocate & initialize the dock_station private data */
- dock_station = kzalloc(sizeof(*dock_station), GFP_KERNEL);
- if (!dock_station)
- return -ENOMEM;
- dock_station->handle = handle;
- dock_station->last_dock_time = jiffies - HZ;
- INIT_LIST_HEAD(&dock_station->dependent_devices);
- INIT_LIST_HEAD(&dock_station->hotplug_devices);
- spin_lock_init(&dock_station->dd_lock);
- spin_lock_init(&dock_station->hp_lock);
-
- /* Find dependent devices */
- acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
- ACPI_UINT32_MAX, find_dock_devices, dock_station,
- NULL);
-
- /* add the dock station as a device dependent on itself */
- dd = alloc_dock_dependent_device(handle);
- if (!dd) {
- kfree(dock_station);
- return -ENOMEM;
- }
- add_dock_dependent_device(dock_station, dd);
-
- /* register for dock events */
- status = acpi_install_notify_handler(dock_station->handle,
- ACPI_SYSTEM_NOTIFY,
- dock_notify, dock_station);
-
- if (ACPI_FAILURE(status)) {
- printk(KERN_ERR PREFIX "Error installing notify handler\n");
- ret = -ENODEV;
- goto dock_add_err;
- }
-
- printk(KERN_INFO PREFIX "%s \n", ACPI_DOCK_DRIVER_NAME);
-
- return 0;
-
-dock_add_err:
- kfree(dock_station);
- kfree(dd);
- return ret;
-}
-
-/**
- * dock_remove - free up resources related to the dock station
- */
-static int dock_remove(void)
-{
- struct dock_dependent_device *dd, *tmp;
- acpi_status status;
-
- if (!dock_station)
- return 0;
-
- /* remove dependent devices */
- list_for_each_entry_safe(dd, tmp, &dock_station->dependent_devices,
- list)
- kfree(dd);
-
- /* remove dock notify handler */
- status = acpi_remove_notify_handler(dock_station->handle,
- ACPI_SYSTEM_NOTIFY,
- dock_notify);
- if (ACPI_FAILURE(status))
- printk(KERN_ERR "Error removing notify handler\n");
-
- /* free dock station memory */
- kfree(dock_station);
- return 0;
-}
-
-/**
- * find_dock - look for a dock station
- * @handle: acpi handle of a device
- * @lvl: unused
- * @context: counter of dock stations found
- * @rv: unused
- *
- * This is called by acpi_walk_namespace to look for dock stations.
- */
-static acpi_status
-find_dock(acpi_handle handle, u32 lvl, void *context, void **rv)
-{
- int *count = (int *)context;
- acpi_status status = AE_OK;
-
- if (is_dock(handle)) {
- if (dock_add(handle) >= 0) {
- (*count)++;
- status = AE_CTRL_TERMINATE;
- }
- }
- return status;
-}
-
-static int __init dock_init(void)
-{
- int num = 0;
-
- dock_station = NULL;
-
- /* look for a dock station */
- acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
- ACPI_UINT32_MAX, find_dock, &num, NULL);
-
- if (!num)
- return -ENODEV;
-
- return 0;
-}
-
-static void __exit dock_exit(void)
-{
- dock_remove();
-}
-
-postcore_initcall(dock_init);
-module_exit(dock_exit);
projects / linux-drm-fsl-dcu.git / commitdiff