diff options
Diffstat (limited to 'drivers/input/serio/serio.c')
| -rw-r--r-- | drivers/input/serio/serio.c | 1049 |
1 files changed, 1049 insertions, 0 deletions
diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c new file mode 100644 index 0000000000..767fc9efb4 --- /dev/null +++ b/drivers/input/serio/serio.c @@ -0,0 +1,1049 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * The Serio abstraction module + * + * Copyright (c) 1999-2004 Vojtech Pavlik + * Copyright (c) 2004 Dmitry Torokhov + * Copyright (c) 2003 Daniele Bellucci + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/stddef.h> +#include <linux/module.h> +#include <linux/serio.h> +#include <linux/errno.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/workqueue.h> +#include <linux/mutex.h> + +MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); +MODULE_DESCRIPTION("Serio abstraction core"); +MODULE_LICENSE("GPL"); + +/* + * serio_mutex protects entire serio subsystem and is taken every time + * serio port or driver registered or unregistered. + */ +static DEFINE_MUTEX(serio_mutex); + +static LIST_HEAD(serio_list); + +static void serio_add_port(struct serio *serio); +static int serio_reconnect_port(struct serio *serio); +static void serio_disconnect_port(struct serio *serio); +static void serio_reconnect_subtree(struct serio *serio); +static void serio_attach_driver(struct serio_driver *drv); + +static int serio_connect_driver(struct serio *serio, struct serio_driver *drv) +{ + int retval; + + mutex_lock(&serio->drv_mutex); + retval = drv->connect(serio, drv); + mutex_unlock(&serio->drv_mutex); + + return retval; +} + +static int serio_reconnect_driver(struct serio *serio) +{ + int retval = -1; + + mutex_lock(&serio->drv_mutex); + if (serio->drv && serio->drv->reconnect) + retval = serio->drv->reconnect(serio); + mutex_unlock(&serio->drv_mutex); + + return retval; +} + +static void serio_disconnect_driver(struct serio *serio) +{ + mutex_lock(&serio->drv_mutex); + if (serio->drv) + serio->drv->disconnect(serio); + mutex_unlock(&serio->drv_mutex); +} + +static int serio_match_port(const struct serio_device_id *ids, struct serio *serio) +{ + while (ids->type || ids->proto) { + if ((ids->type == SERIO_ANY || ids->type == serio->id.type) && + (ids->proto == SERIO_ANY || ids->proto == serio->id.proto) && + (ids->extra == SERIO_ANY || ids->extra == serio->id.extra) && + (ids->id == SERIO_ANY || ids->id == serio->id.id)) + return 1; + ids++; + } + return 0; +} + +/* + * Basic serio -> driver core mappings + */ + +static int serio_bind_driver(struct serio *serio, struct serio_driver *drv) +{ + int error; + + if (serio_match_port(drv->id_table, serio)) { + + serio->dev.driver = &drv->driver; + if (serio_connect_driver(serio, drv)) { + serio->dev.driver = NULL; + return -ENODEV; + } + + error = device_bind_driver(&serio->dev); + if (error) { + dev_warn(&serio->dev, + "device_bind_driver() failed for %s (%s) and %s, error: %d\n", + serio->phys, serio->name, + drv->description, error); + serio_disconnect_driver(serio); + serio->dev.driver = NULL; + return error; + } + } + return 0; +} + +static void serio_find_driver(struct serio *serio) +{ + int error; + + error = device_attach(&serio->dev); + if (error < 0 && error != -EPROBE_DEFER) + dev_warn(&serio->dev, + "device_attach() failed for %s (%s), error: %d\n", + serio->phys, serio->name, error); +} + + +/* + * Serio event processing. + */ + +enum serio_event_type { + SERIO_RESCAN_PORT, + SERIO_RECONNECT_PORT, + SERIO_RECONNECT_SUBTREE, + SERIO_REGISTER_PORT, + SERIO_ATTACH_DRIVER, +}; + +struct serio_event { + enum serio_event_type type; + void *object; + struct module *owner; + struct list_head node; +}; + +static DEFINE_SPINLOCK(serio_event_lock); /* protects serio_event_list */ +static LIST_HEAD(serio_event_list); + +static struct serio_event *serio_get_event(void) +{ + struct serio_event *event = NULL; + unsigned long flags; + + spin_lock_irqsave(&serio_event_lock, flags); + + if (!list_empty(&serio_event_list)) { + event = list_first_entry(&serio_event_list, + struct serio_event, node); + list_del_init(&event->node); + } + + spin_unlock_irqrestore(&serio_event_lock, flags); + return event; +} + +static void serio_free_event(struct serio_event *event) +{ + module_put(event->owner); + kfree(event); +} + +static void serio_remove_duplicate_events(void *object, + enum serio_event_type type) +{ + struct serio_event *e, *next; + unsigned long flags; + + spin_lock_irqsave(&serio_event_lock, flags); + + list_for_each_entry_safe(e, next, &serio_event_list, node) { + if (object == e->object) { + /* + * If this event is of different type we should not + * look further - we only suppress duplicate events + * that were sent back-to-back. + */ + if (type != e->type) + break; + + list_del_init(&e->node); + serio_free_event(e); + } + } + + spin_unlock_irqrestore(&serio_event_lock, flags); +} + +static void serio_handle_event(struct work_struct *work) +{ + struct serio_event *event; + + mutex_lock(&serio_mutex); + + while ((event = serio_get_event())) { + + switch (event->type) { + + case SERIO_REGISTER_PORT: + serio_add_port(event->object); + break; + + case SERIO_RECONNECT_PORT: + serio_reconnect_port(event->object); + break; + + case SERIO_RESCAN_PORT: + serio_disconnect_port(event->object); + serio_find_driver(event->object); + break; + + case SERIO_RECONNECT_SUBTREE: + serio_reconnect_subtree(event->object); + break; + + case SERIO_ATTACH_DRIVER: + serio_attach_driver(event->object); + break; + } + + serio_remove_duplicate_events(event->object, event->type); + serio_free_event(event); + } + + mutex_unlock(&serio_mutex); +} + +static DECLARE_WORK(serio_event_work, serio_handle_event); + +static int serio_queue_event(void *object, struct module *owner, + enum serio_event_type event_type) +{ + unsigned long flags; + struct serio_event *event; + int retval = 0; + + spin_lock_irqsave(&serio_event_lock, flags); + + /* + * Scan event list for the other events for the same serio port, + * starting with the most recent one. If event is the same we + * do not need add new one. If event is of different type we + * need to add this event and should not look further because + * we need to preseve sequence of distinct events. + */ + list_for_each_entry_reverse(event, &serio_event_list, node) { + if (event->object == object) { + if (event->type == event_type) + goto out; + break; + } + } + + event = kmalloc(sizeof(struct serio_event), GFP_ATOMIC); + if (!event) { + pr_err("Not enough memory to queue event %d\n", event_type); + retval = -ENOMEM; + goto out; + } + + if (!try_module_get(owner)) { + pr_warn("Can't get module reference, dropping event %d\n", + event_type); + kfree(event); + retval = -EINVAL; + goto out; + } + + event->type = event_type; + event->object = object; + event->owner = owner; + + list_add_tail(&event->node, &serio_event_list); + queue_work(system_long_wq, &serio_event_work); + +out: + spin_unlock_irqrestore(&serio_event_lock, flags); + return retval; +} + +/* + * Remove all events that have been submitted for a given + * object, be it serio port or driver. + */ +static void serio_remove_pending_events(void *object) +{ + struct serio_event *event, *next; + unsigned long flags; + + spin_lock_irqsave(&serio_event_lock, flags); + + list_for_each_entry_safe(event, next, &serio_event_list, node) { + if (event->object == object) { + list_del_init(&event->node); + serio_free_event(event); + } + } + + spin_unlock_irqrestore(&serio_event_lock, flags); +} + +/* + * Locate child serio port (if any) that has not been fully registered yet. + * + * Children are registered by driver's connect() handler so there can't be a + * grandchild pending registration together with a child. + */ +static struct serio *serio_get_pending_child(struct serio *parent) +{ + struct serio_event *event; + struct serio *serio, *child = NULL; + unsigned long flags; + + spin_lock_irqsave(&serio_event_lock, flags); + + list_for_each_entry(event, &serio_event_list, node) { + if (event->type == SERIO_REGISTER_PORT) { + serio = event->object; + if (serio->parent == parent) { + child = serio; + break; + } + } + } + + spin_unlock_irqrestore(&serio_event_lock, flags); + return child; +} + +/* + * Serio port operations + */ + +static ssize_t serio_show_description(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + return sprintf(buf, "%s\n", serio->name); +} + +static ssize_t modalias_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + + return sprintf(buf, "serio:ty%02Xpr%02Xid%02Xex%02X\n", + serio->id.type, serio->id.proto, serio->id.id, serio->id.extra); +} + +static ssize_t type_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + return sprintf(buf, "%02x\n", serio->id.type); +} + +static ssize_t proto_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + return sprintf(buf, "%02x\n", serio->id.proto); +} + +static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + return sprintf(buf, "%02x\n", serio->id.id); +} + +static ssize_t extra_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + return sprintf(buf, "%02x\n", serio->id.extra); +} + +static ssize_t drvctl_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) +{ + struct serio *serio = to_serio_port(dev); + struct device_driver *drv; + int error; + + error = mutex_lock_interruptible(&serio_mutex); + if (error) + return error; + + if (!strncmp(buf, "none", count)) { + serio_disconnect_port(serio); + } else if (!strncmp(buf, "reconnect", count)) { + serio_reconnect_subtree(serio); + } else if (!strncmp(buf, "rescan", count)) { + serio_disconnect_port(serio); + serio_find_driver(serio); + serio_remove_duplicate_events(serio, SERIO_RESCAN_PORT); + } else if ((drv = driver_find(buf, &serio_bus)) != NULL) { + serio_disconnect_port(serio); + error = serio_bind_driver(serio, to_serio_driver(drv)); + serio_remove_duplicate_events(serio, SERIO_RESCAN_PORT); + } else { + error = -EINVAL; + } + + mutex_unlock(&serio_mutex); + + return error ? error : count; +} + +static ssize_t serio_show_bind_mode(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + return sprintf(buf, "%s\n", serio->manual_bind ? "manual" : "auto"); +} + +static ssize_t serio_set_bind_mode(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) +{ + struct serio *serio = to_serio_port(dev); + int retval; + + retval = count; + if (!strncmp(buf, "manual", count)) { + serio->manual_bind = true; + } else if (!strncmp(buf, "auto", count)) { + serio->manual_bind = false; + } else { + retval = -EINVAL; + } + + return retval; +} + +static ssize_t firmware_id_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct serio *serio = to_serio_port(dev); + + return sprintf(buf, "%s\n", serio->firmware_id); +} + +static DEVICE_ATTR_RO(type); +static DEVICE_ATTR_RO(proto); +static DEVICE_ATTR_RO(id); +static DEVICE_ATTR_RO(extra); + +static struct attribute *serio_device_id_attrs[] = { + &dev_attr_type.attr, + &dev_attr_proto.attr, + &dev_attr_id.attr, + &dev_attr_extra.attr, + NULL +}; + +static const struct attribute_group serio_id_attr_group = { + .name = "id", + .attrs = serio_device_id_attrs, +}; + +static DEVICE_ATTR_RO(modalias); +static DEVICE_ATTR_WO(drvctl); +static DEVICE_ATTR(description, S_IRUGO, serio_show_description, NULL); +static DEVICE_ATTR(bind_mode, S_IWUSR | S_IRUGO, serio_show_bind_mode, serio_set_bind_mode); +static DEVICE_ATTR_RO(firmware_id); + +static struct attribute *serio_device_attrs[] = { + &dev_attr_modalias.attr, + &dev_attr_description.attr, + &dev_attr_drvctl.attr, + &dev_attr_bind_mode.attr, + &dev_attr_firmware_id.attr, + NULL +}; + +static const struct attribute_group serio_device_attr_group = { + .attrs = serio_device_attrs, +}; + +static const struct attribute_group *serio_device_attr_groups[] = { + &serio_id_attr_group, + &serio_device_attr_group, + NULL +}; + +static void serio_release_port(struct device *dev) +{ + struct serio *serio = to_serio_port(dev); + + kfree(serio); + module_put(THIS_MODULE); +} + +/* + * Prepare serio port for registration. + */ +static void serio_init_port(struct serio *serio) +{ + static atomic_t serio_no = ATOMIC_INIT(-1); + + __module_get(THIS_MODULE); + + INIT_LIST_HEAD(&serio->node); + INIT_LIST_HEAD(&serio->child_node); + INIT_LIST_HEAD(&serio->children); + spin_lock_init(&serio->lock); + mutex_init(&serio->drv_mutex); + device_initialize(&serio->dev); + dev_set_name(&serio->dev, "serio%lu", + (unsigned long)atomic_inc_return(&serio_no)); + serio->dev.bus = &serio_bus; + serio->dev.release = serio_release_port; + serio->dev.groups = serio_device_attr_groups; + if (serio->parent) { + serio->dev.parent = &serio->parent->dev; + serio->depth = serio->parent->depth + 1; + } else + serio->depth = 0; + lockdep_set_subclass(&serio->lock, serio->depth); +} + +/* + * Complete serio port registration. + * Driver core will attempt to find appropriate driver for the port. + */ +static void serio_add_port(struct serio *serio) +{ + struct serio *parent = serio->parent; + int error; + + if (parent) { + serio_pause_rx(parent); + list_add_tail(&serio->child_node, &parent->children); + serio_continue_rx(parent); + } + + list_add_tail(&serio->node, &serio_list); + + if (serio->start) + serio->start(serio); + + error = device_add(&serio->dev); + if (error) + dev_err(&serio->dev, + "device_add() failed for %s (%s), error: %d\n", + serio->phys, serio->name, error); +} + +/* + * serio_destroy_port() completes unregistration process and removes + * port from the system + */ +static void serio_destroy_port(struct serio *serio) +{ + struct serio *child; + + while ((child = serio_get_pending_child(serio)) != NULL) { + serio_remove_pending_events(child); + put_device(&child->dev); + } + + if (serio->stop) + serio->stop(serio); + + if (serio->parent) { + serio_pause_rx(serio->parent); + list_del_init(&serio->child_node); + serio_continue_rx(serio->parent); + serio->parent = NULL; + } + + if (device_is_registered(&serio->dev)) + device_del(&serio->dev); + + list_del_init(&serio->node); + serio_remove_pending_events(serio); + put_device(&serio->dev); +} + +/* + * Reconnect serio port (re-initialize attached device). + * If reconnect fails (old device is no longer attached or + * there was no device to begin with) we do full rescan in + * hope of finding a driver for the port. + */ +static int serio_reconnect_port(struct serio *serio) +{ + int error = serio_reconnect_driver(serio); + + if (error) { + serio_disconnect_port(serio); + serio_find_driver(serio); + } + + return error; +} + +/* + * Reconnect serio port and all its children (re-initialize attached + * devices). + */ +static void serio_reconnect_subtree(struct serio *root) +{ + struct serio *s = root; + int error; + + do { + error = serio_reconnect_port(s); + if (!error) { + /* + * Reconnect was successful, move on to do the + * first child. + */ + if (!list_empty(&s->children)) { + s = list_first_entry(&s->children, + struct serio, child_node); + continue; + } + } + + /* + * Either it was a leaf node or reconnect failed and it + * became a leaf node. Continue reconnecting starting with + * the next sibling of the parent node. + */ + while (s != root) { + struct serio *parent = s->parent; + + if (!list_is_last(&s->child_node, &parent->children)) { + s = list_entry(s->child_node.next, + struct serio, child_node); + break; + } + + s = parent; + } + } while (s != root); +} + +/* + * serio_disconnect_port() unbinds a port from its driver. As a side effect + * all children ports are unbound and destroyed. + */ +static void serio_disconnect_port(struct serio *serio) +{ + struct serio *s = serio; + + /* + * Children ports should be disconnected and destroyed + * first; we travel the tree in depth-first order. + */ + while (!list_empty(&serio->children)) { + + /* Locate a leaf */ + while (!list_empty(&s->children)) + s = list_first_entry(&s->children, + struct serio, child_node); + + /* + * Prune this leaf node unless it is the one we + * started with. + */ + if (s != serio) { + struct serio *parent = s->parent; + + device_release_driver(&s->dev); + serio_destroy_port(s); + + s = parent; + } + } + + /* + * OK, no children left, now disconnect this port. + */ + device_release_driver(&serio->dev); +} + +void serio_rescan(struct serio *serio) +{ + serio_queue_event(serio, NULL, SERIO_RESCAN_PORT); +} +EXPORT_SYMBOL(serio_rescan); + +void serio_reconnect(struct serio *serio) +{ + serio_queue_event(serio, NULL, SERIO_RECONNECT_SUBTREE); +} +EXPORT_SYMBOL(serio_reconnect); + +/* + * Submits register request to kseriod for subsequent execution. + * Note that port registration is always asynchronous. + */ +void __serio_register_port(struct serio *serio, struct module *owner) +{ + serio_init_port(serio); + serio_queue_event(serio, owner, SERIO_REGISTER_PORT); +} +EXPORT_SYMBOL(__serio_register_port); + +/* + * Synchronously unregisters serio port. + */ +void serio_unregister_port(struct serio *serio) +{ + mutex_lock(&serio_mutex); + serio_disconnect_port(serio); + serio_destroy_port(serio); + mutex_unlock(&serio_mutex); +} +EXPORT_SYMBOL(serio_unregister_port); + +/* + * Safely unregisters children ports if they are present. + */ +void serio_unregister_child_port(struct serio *serio) +{ + struct serio *s, *next; + + mutex_lock(&serio_mutex); + list_for_each_entry_safe(s, next, &serio->children, child_node) { + serio_disconnect_port(s); + serio_destroy_port(s); + } + mutex_unlock(&serio_mutex); +} +EXPORT_SYMBOL(serio_unregister_child_port); + + +/* + * Serio driver operations + */ + +static ssize_t description_show(struct device_driver *drv, char *buf) +{ + struct serio_driver *driver = to_serio_driver(drv); + return sprintf(buf, "%s\n", driver->description ? driver->description : "(none)"); +} +static DRIVER_ATTR_RO(description); + +static ssize_t bind_mode_show(struct device_driver *drv, char *buf) +{ + struct serio_driver *serio_drv = to_serio_driver(drv); + return sprintf(buf, "%s\n", serio_drv->manual_bind ? "manual" : "auto"); +} + +static ssize_t bind_mode_store(struct device_driver *drv, const char *buf, size_t count) +{ + struct serio_driver *serio_drv = to_serio_driver(drv); + int retval; + + retval = count; + if (!strncmp(buf, "manual", count)) { + serio_drv->manual_bind = true; + } else if (!strncmp(buf, "auto", count)) { + serio_drv->manual_bind = false; + } else { + retval = -EINVAL; + } + + return retval; +} +static DRIVER_ATTR_RW(bind_mode); + +static struct attribute *serio_driver_attrs[] = { + &driver_attr_description.attr, + &driver_attr_bind_mode.attr, + NULL, +}; +ATTRIBUTE_GROUPS(serio_driver); + +static int serio_driver_probe(struct device *dev) +{ + struct serio *serio = to_serio_port(dev); + struct serio_driver *drv = to_serio_driver(dev->driver); + + return serio_connect_driver(serio, drv); +} + +static void serio_driver_remove(struct device *dev) +{ + struct serio *serio = to_serio_port(dev); + + serio_disconnect_driver(serio); +} + +static void serio_cleanup(struct serio *serio) +{ + mutex_lock(&serio->drv_mutex); + if (serio->drv && serio->drv->cleanup) + serio->drv->cleanup(serio); + mutex_unlock(&serio->drv_mutex); +} + +static void serio_shutdown(struct device *dev) +{ + struct serio *serio = to_serio_port(dev); + + serio_cleanup(serio); +} + +static void serio_attach_driver(struct serio_driver *drv) +{ + int error; + + error = driver_attach(&drv->driver); + if (error) + pr_warn("driver_attach() failed for %s with error %d\n", + drv->driver.name, error); +} + +int __serio_register_driver(struct serio_driver *drv, struct module *owner, const char *mod_name) +{ + bool manual_bind = drv->manual_bind; + int error; + + drv->driver.bus = &serio_bus; + drv->driver.owner = owner; + drv->driver.mod_name = mod_name; + + /* + * Temporarily disable automatic binding because probing + * takes long time and we are better off doing it in kseriod + */ + drv->manual_bind = true; + + error = driver_register(&drv->driver); + if (error) { + pr_err("driver_register() failed for %s, error: %d\n", + drv->driver.name, error); + return error; + } + + /* + * Restore original bind mode and let kseriod bind the + * driver to free ports + */ + if (!manual_bind) { + drv->manual_bind = false; + error = serio_queue_event(drv, NULL, SERIO_ATTACH_DRIVER); + if (error) { + driver_unregister(&drv->driver); + return error; + } + } + + return 0; +} +EXPORT_SYMBOL(__serio_register_driver); + +void serio_unregister_driver(struct serio_driver *drv) +{ + struct serio *serio; + + mutex_lock(&serio_mutex); + + drv->manual_bind = true; /* so serio_find_driver ignores it */ + serio_remove_pending_events(drv); + +start_over: + list_for_each_entry(serio, &serio_list, node) { + if (serio->drv == drv) { + serio_disconnect_port(serio); + serio_find_driver(serio); + /* we could've deleted some ports, restart */ + goto start_over; + } + } + + driver_unregister(&drv->driver); + mutex_unlock(&serio_mutex); +} +EXPORT_SYMBOL(serio_unregister_driver); + +static void serio_set_drv(struct serio *serio, struct serio_driver *drv) +{ + serio_pause_rx(serio); + serio->drv = drv; + serio_continue_rx(serio); +} + +static int serio_bus_match(struct device *dev, struct device_driver *drv) +{ + struct serio *serio = to_serio_port(dev); + struct serio_driver *serio_drv = to_serio_driver(drv); + + if (serio->manual_bind || serio_drv->manual_bind) + return 0; + + return serio_match_port(serio_drv->id_table, serio); +} + +#define SERIO_ADD_UEVENT_VAR(fmt, val...) \ + do { \ + int err = add_uevent_var(env, fmt, val); \ + if (err) \ + return err; \ + } while (0) + +static int serio_uevent(const struct device *dev, struct kobj_uevent_env *env) +{ + const struct serio *serio; + + if (!dev) + return -ENODEV; + + serio = to_serio_port(dev); + + SERIO_ADD_UEVENT_VAR("SERIO_TYPE=%02x", serio->id.type); + SERIO_ADD_UEVENT_VAR("SERIO_PROTO=%02x", serio->id.proto); + SERIO_ADD_UEVENT_VAR("SERIO_ID=%02x", serio->id.id); + SERIO_ADD_UEVENT_VAR("SERIO_EXTRA=%02x", serio->id.extra); + + SERIO_ADD_UEVENT_VAR("MODALIAS=serio:ty%02Xpr%02Xid%02Xex%02X", + serio->id.type, serio->id.proto, serio->id.id, serio->id.extra); + + if (serio->firmware_id[0]) + SERIO_ADD_UEVENT_VAR("SERIO_FIRMWARE_ID=%s", + serio->firmware_id); + + return 0; +} +#undef SERIO_ADD_UEVENT_VAR + +#ifdef CONFIG_PM +static int serio_suspend(struct device *dev) +{ + struct serio *serio = to_serio_port(dev); + + serio_cleanup(serio); + + return 0; +} + +static int serio_resume(struct device *dev) +{ + struct serio *serio = to_serio_port(dev); + int error = -ENOENT; + + mutex_lock(&serio->drv_mutex); + if (serio->drv && serio->drv->fast_reconnect) { + error = serio->drv->fast_reconnect(serio); + if (error && error != -ENOENT) + dev_warn(dev, "fast reconnect failed with error %d\n", + error); + } + mutex_unlock(&serio->drv_mutex); + + if (error) { + /* + * Driver reconnect can take a while, so better let + * kseriod deal with it. + */ + serio_queue_event(serio, NULL, SERIO_RECONNECT_PORT); + } + + return 0; +} + +static const struct dev_pm_ops serio_pm_ops = { + .suspend = serio_suspend, + .resume = serio_resume, + .poweroff = serio_suspend, + .restore = serio_resume, +}; +#endif /* CONFIG_PM */ + +/* called from serio_driver->connect/disconnect methods under serio_mutex */ +int serio_open(struct serio *serio, struct serio_driver *drv) +{ + serio_set_drv(serio, drv); + + if (serio->open && serio->open(serio)) { + serio_set_drv(serio, NULL); + return -1; + } + return 0; +} +EXPORT_SYMBOL(serio_open); + +/* called from serio_driver->connect/disconnect methods under serio_mutex */ +void serio_close(struct serio *serio) +{ + if (serio->close) + serio->close(serio); + + serio_set_drv(serio, NULL); +} +EXPORT_SYMBOL(serio_close); + +irqreturn_t serio_interrupt(struct serio *serio, + unsigned char data, unsigned int dfl) +{ + unsigned long flags; + irqreturn_t ret = IRQ_NONE; + + spin_lock_irqsave(&serio->lock, flags); + + if (likely(serio->drv)) { + ret = serio->drv->interrupt(serio, data, dfl); + } else if (!dfl && device_is_registered(&serio->dev)) { + serio_rescan(serio); + ret = IRQ_HANDLED; + } + + spin_unlock_irqrestore(&serio->lock, flags); + + return ret; +} +EXPORT_SYMBOL(serio_interrupt); + +struct bus_type serio_bus = { + .name = "serio", + .drv_groups = serio_driver_groups, + .match = serio_bus_match, + .uevent = serio_uevent, + .probe = serio_driver_probe, + .remove = serio_driver_remove, + .shutdown = serio_shutdown, +#ifdef CONFIG_PM + .pm = &serio_pm_ops, +#endif +}; +EXPORT_SYMBOL(serio_bus); + +static int __init serio_init(void) +{ + int error; + + error = bus_register(&serio_bus); + if (error) { + pr_err("Failed to register serio bus, error: %d\n", error); + return error; + } + + return 0; +} + +static void __exit serio_exit(void) +{ + bus_unregister(&serio_bus); + + /* + * There should not be any outstanding events but work may + * still be scheduled so simply cancel it. + */ + cancel_work_sync(&serio_event_work); +} + +subsys_initcall(serio_init); +module_exit(serio_exit); |