diff options
| -rw-r--r-- | drivers/input/mouse/psmouse-base.c | 4 | ||||
| -rw-r--r-- | drivers/input/serio/serio.c | 124 | ||||
| -rw-r--r-- | include/linux/serio.h | 4 |
3 files changed, 86 insertions, 46 deletions
diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c index 73a7af2542a..cd9d0c97e42 100644 --- a/drivers/input/mouse/psmouse-base.c +++ b/drivers/input/mouse/psmouse-base.c @@ -1584,10 +1584,10 @@ static ssize_t psmouse_attr_set_protocol(struct psmouse *psmouse, void *data, co if (!new_dev) return -ENOMEM; - while (serio->child) { + while (!list_empty(&serio->children)) { if (++retry > 3) { printk(KERN_WARNING - "psmouse: failed to destroy child port, " + "psmouse: failed to destroy children ports, " "protocol change aborted.\n"); input_free_device(new_dev); return -EIO; diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c index 8a426375fcb..405bf214527 100644 --- a/drivers/input/serio/serio.c +++ b/drivers/input/serio/serio.c @@ -55,7 +55,7 @@ static struct bus_type serio_bus; 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_chain(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) @@ -151,7 +151,7 @@ static void serio_find_driver(struct serio *serio) enum serio_event_type { SERIO_RESCAN_PORT, SERIO_RECONNECT_PORT, - SERIO_RECONNECT_CHAIN, + SERIO_RECONNECT_SUBTREE, SERIO_REGISTER_PORT, SERIO_ATTACH_DRIVER, }; @@ -291,8 +291,8 @@ static void serio_handle_event(void) serio_find_driver(event->object); break; - case SERIO_RECONNECT_CHAIN: - serio_reconnect_chain(event->object); + case SERIO_RECONNECT_SUBTREE: + serio_reconnect_subtree(event->object); break; case SERIO_ATTACH_DRIVER: @@ -329,12 +329,10 @@ static void serio_remove_pending_events(void *object) } /* - * Destroy child serio port (if any) that has not been fully registered yet. + * Locate child serio port (if any) that has not been fully registered yet. * - * Note that we rely on the fact that port can have only one child and therefore - * only one child registration request can be pending. Additionally, children - * are registered by driver's connect() handler so there can't be a grandchild - * pending registration together with a child. + * 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) { @@ -448,7 +446,7 @@ static ssize_t serio_rebind_driver(struct device *dev, struct device_attribute * if (!strncmp(buf, "none", count)) { serio_disconnect_port(serio); } else if (!strncmp(buf, "reconnect", count)) { - serio_reconnect_chain(serio); + serio_reconnect_subtree(serio); } else if (!strncmp(buf, "rescan", count)) { serio_disconnect_port(serio); serio_find_driver(serio); @@ -515,6 +513,8 @@ static void serio_init_port(struct serio *serio) __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); @@ -537,12 +537,13 @@ static void serio_init_port(struct serio *serio) */ static void serio_add_port(struct serio *serio) { + struct serio *parent = serio->parent; int error; - if (serio->parent) { - serio_pause_rx(serio->parent); - serio->parent->child = serio; - serio_continue_rx(serio->parent); + 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); @@ -558,15 +559,14 @@ static void serio_add_port(struct serio *serio) } /* - * serio_destroy_port() completes deregistration process and removes + * serio_destroy_port() completes unregistration process and removes * port from the system */ static void serio_destroy_port(struct serio *serio) { struct serio *child; - child = serio_get_pending_child(serio); - if (child) { + while ((child = serio_get_pending_child(serio)) != NULL) { serio_remove_pending_events(child); put_device(&child->dev); } @@ -576,7 +576,7 @@ static void serio_destroy_port(struct serio *serio) if (serio->parent) { serio_pause_rx(serio->parent); - serio->parent->child = NULL; + list_del_init(&serio->child_node); serio_continue_rx(serio->parent); serio->parent = NULL; } @@ -608,46 +608,82 @@ static int serio_reconnect_port(struct serio *serio) } /* - * Reconnect serio port and all its children (re-initialize attached devices) + * Reconnect serio port and all its children (re-initialize attached + * devices). */ -static void serio_reconnect_chain(struct serio *serio) +static void serio_reconnect_subtree(struct serio *root) { + struct serio *s = root; + int error; + do { - if (serio_reconnect_port(serio)) { - /* Ok, old children are now gone, we are done */ - break; + 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; + } } - serio = serio->child; - } while (serio); + + /* + * 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 child ports are unbound and destroyed. + * all children ports are unbound and destroyed. */ static void serio_disconnect_port(struct serio *serio) { - struct serio *s, *parent; + 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); - if (serio->child) { /* - * Children ports should be disconnected and destroyed - * first, staring with the leaf one, since we don't want - * to do recursion + * Prune this leaf node unless it is the one we + * started with. */ - for (s = serio; s->child; s = s->child) - /* empty */; - - do { - parent = s->parent; + if (s != serio) { + struct serio *parent = s->parent; device_release_driver(&s->dev); serio_destroy_port(s); - } while ((s = parent) != serio); + + s = parent; + } } /* - * Ok, no children left, now disconnect this port + * OK, no children left, now disconnect this port. */ device_release_driver(&serio->dev); } @@ -660,7 +696,7 @@ EXPORT_SYMBOL(serio_rescan); void serio_reconnect(struct serio *serio) { - serio_queue_event(serio, NULL, SERIO_RECONNECT_CHAIN); + serio_queue_event(serio, NULL, SERIO_RECONNECT_SUBTREE); } EXPORT_SYMBOL(serio_reconnect); @@ -688,14 +724,16 @@ void serio_unregister_port(struct serio *serio) EXPORT_SYMBOL(serio_unregister_port); /* - * Safely unregisters child port if one is present. + * Safely unregisters children ports if they are present. */ void serio_unregister_child_port(struct serio *serio) { + struct serio *s, *next; + mutex_lock(&serio_mutex); - if (serio->child) { - serio_disconnect_port(serio->child); - serio_destroy_port(serio->child); + list_for_each_entry_safe(s, next, &serio->children, child_node) { + serio_disconnect_port(s); + serio_destroy_port(s); } mutex_unlock(&serio_mutex); } diff --git a/include/linux/serio.h b/include/linux/serio.h index 111ad501b05..109b237603b 100644 --- a/include/linux/serio.h +++ b/include/linux/serio.h @@ -41,7 +41,9 @@ struct serio { int (*start)(struct serio *); void (*stop)(struct serio *); - struct serio *parent, *child; + struct serio *parent; + struct list_head child_node; /* Entry in parent->children list */ + struct list_head children; unsigned int depth; /* level of nesting in serio hierarchy */ struct serio_driver *drv; /* accessed from interrupt, must be protected by serio->lock and serio->sem */ |