spinlock_t dd_lock;
struct mutex hp_lock;
struct list_head dependent_devices;
- struct list_head hotplug_devices;
struct list_head sibling;
struct platform_device *dock_device;
};
static LIST_HEAD(dock_stations);
static int dock_station_count;
+static DEFINE_MUTEX(hotplug_lock);
struct dock_dependent_device {
struct list_head list;
- struct list_head hotplug_list;
acpi_handle handle;
- const struct acpi_dock_ops *ops;
- void *context;
+ const struct acpi_dock_ops *hp_ops;
+ void *hp_context;
+ unsigned int hp_refcount;
+ void (*hp_release)(void *);
};
#define DOCK_DOCKING 0x00000001
dd->handle = handle;
INIT_LIST_HEAD(&dd->list);
- INIT_LIST_HEAD(&dd->hotplug_list);
spin_lock(&ds->dd_lock);
list_add_tail(&dd->list, &ds->dependent_devices);
}
/**
- * 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
+ * dock_init_hotplug - Initialize a hotplug device on a docking station.
+ * @dd: Dock-dependent device.
+ * @ops: Dock operations to attach to the dependent device.
+ * @context: Data to pass to the @ops callbacks and @release.
+ * @init: Optional initialization routine to run after setting up context.
+ * @release: Optional release routine to run on removal.
*/
-static void
-dock_add_hotplug_device(struct dock_station *ds,
- struct dock_dependent_device *dd)
+static int dock_init_hotplug(struct dock_dependent_device *dd,
+ const struct acpi_dock_ops *ops, void *context,
+ void (*init)(void *), void (*release)(void *))
{
- mutex_lock(&ds->hp_lock);
- list_add_tail(&dd->hotplug_list, &ds->hotplug_devices);
- mutex_unlock(&ds->hp_lock);
+ int ret = 0;
+
+ mutex_lock(&hotplug_lock);
+
+ if (dd->hp_context) {
+ ret = -EEXIST;
+ } else {
+ dd->hp_refcount = 1;
+ dd->hp_ops = ops;
+ dd->hp_context = context;
+ dd->hp_release = release;
+ }
+
+ if (!WARN_ON(ret) && init)
+ init(context);
+
+ mutex_unlock(&hotplug_lock);
+ return ret;
}
/**
- * dock_del_hotplug_device - remove a hotplug handler from the dock station
- * @ds: The dock station
- * @dd: the dependent device struct
+ * dock_release_hotplug - Decrement hotplug reference counter of dock device.
+ * @dd: Dock-dependent device.
*
- * Delete the dependent device from the dock's hotplug device list
+ * Decrement the reference counter of @dd and if 0, detach its hotplug
+ * operations from it, reset its context pointer and run the optional release
+ * routine if present.
*/
-static void
-dock_del_hotplug_device(struct dock_station *ds,
- struct dock_dependent_device *dd)
+static void dock_release_hotplug(struct dock_dependent_device *dd)
{
- mutex_lock(&ds->hp_lock);
- list_del(&dd->hotplug_list);
- mutex_unlock(&ds->hp_lock);
+ void (*release)(void *) = NULL;
+ void *context = NULL;
+
+ mutex_lock(&hotplug_lock);
+
+ if (dd->hp_context && !--dd->hp_refcount) {
+ dd->hp_ops = NULL;
+ context = dd->hp_context;
+ dd->hp_context = NULL;
+ release = dd->hp_release;
+ dd->hp_release = NULL;
+ }
+
+ if (release && context)
+ release(context);
+
+ mutex_unlock(&hotplug_lock);
+}
+
+static void dock_hotplug_event(struct dock_dependent_device *dd, u32 event,
+ bool uevent)
+{
+ acpi_notify_handler cb = NULL;
+ bool run = false;
+
+ mutex_lock(&hotplug_lock);
+
+ if (dd->hp_context) {
+ run = true;
+ dd->hp_refcount++;
+ if (dd->hp_ops)
+ cb = uevent ? dd->hp_ops->uevent : dd->hp_ops->handler;
+ }
+
+ mutex_unlock(&hotplug_lock);
+
+ if (!run)
+ return;
+
+ if (cb)
+ cb(dd->handle, event, dd->hp_context);
+
+ dock_release_hotplug(dd);
}
/**
/*
* First call driver specific hotplug functions
*/
- list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list)
- if (dd->ops && dd->ops->handler)
- dd->ops->handler(dd->handle, event, dd->context);
+ list_for_each_entry(dd, &ds->dependent_devices, list)
+ dock_hotplug_event(dd, event, false);
/*
* Now make sure that an acpi_device is created for each
if (num == DOCK_EVENT)
kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
- list_for_each_entry(dd, &ds->hotplug_devices, hotplug_list)
- if (dd->ops && dd->ops->uevent)
- dd->ops->uevent(dd->handle, event, dd->context);
+ list_for_each_entry(dd, &ds->dependent_devices, list)
+ dock_hotplug_event(dd, event, true);
if (num != DOCK_EVENT)
kobject_uevent_env(&dev->kobj, KOBJ_CHANGE, envp);
* @handle: the handle of the device
* @ops: handlers to call after docking
* @context: device specific data
+ * @init: Optional initialization routine to run after registration
+ * @release: Optional release routine to run on unregistration
*
* 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, const struct acpi_dock_ops *ops,
- void *context)
+int register_hotplug_dock_device(acpi_handle handle,
+ const struct acpi_dock_ops *ops, void *context,
+ void (*init)(void *), void (*release)(void *))
{
struct dock_dependent_device *dd;
struct dock_station *dock_station;
int ret = -EINVAL;
+ if (WARN_ON(!context))
+ return -EINVAL;
+
if (!dock_station_count)
return -ENODEV;
* ops
*/
dd = find_dock_dependent_device(dock_station, handle);
- if (dd) {
- dd->ops = ops;
- dd->context = context;
- dock_add_hotplug_device(dock_station, dd);
+ if (dd && !dock_init_hotplug(dd, ops, context, init, release))
ret = 0;
- }
}
return ret;
list_for_each_entry(dock_station, &dock_stations, sibling) {
dd = find_dock_dependent_device(dock_station, handle);
if (dd)
- dock_del_hotplug_device(dock_station, dd);
+ dock_release_hotplug(dd);
}
}
EXPORT_SYMBOL_GPL(unregister_hotplug_dock_device);
mutex_init(&dock_station->hp_lock);
spin_lock_init(&dock_station->dd_lock);
INIT_LIST_HEAD(&dock_station->sibling);
- INIT_LIST_HEAD(&dock_station->hotplug_devices);
ATOMIC_INIT_NOTIFIER_HEAD(&dock_notifier_list);
INIT_LIST_HEAD(&dock_station->dependent_devices);
projects / linux-imx.git / blobdiff