Some (rare) serio devices need to have multiple serio children. One of
the examples is PS/2 multiplexer present on several TQC STKxxx boards,
which connect PS/2 keyboard and mouse to single tty port.
Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@xxxxxxxxx>
---
drivers/input/mouse/psmouse-base.c | 2 +-
drivers/input/mouse/synaptics.c | 11 +++-
drivers/input/serio/serio.c | 114 +++++++++++++++++++-----------------
include/linux/serio.h | 5 +-
4 files changed, 73 insertions(+), 59 deletions(-)
diff --git a/drivers/input/mouse/psmouse-base.c b/drivers/input/mouse/psmouse-base.c
index 979c502..0eeed6c 100644
--- a/drivers/input/mouse/psmouse-base.c
+++ b/drivers/input/mouse/psmouse-base.c
@@ -1582,7 +1582,7 @@ 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, "
diff --git a/drivers/input/mouse/synaptics.c b/drivers/input/mouse/synaptics.c
index 705589d..9295ad0 100644
--- a/drivers/input/mouse/synaptics.c
+++ b/drivers/input/mouse/synaptics.c
@@ -315,7 +315,9 @@ static void synaptics_pass_pt_packet(struct serio *ptport, unsigned char *packet
static void synaptics_pt_activate(struct psmouse *psmouse)
{
- struct serio *ptport = psmouse->ps2dev.serio->child;
+ struct serio *ptport =
+ list_first_entry(&psmouse->ps2dev.serio->children,
+ struct serio, child_list);
struct psmouse *child = serio_get_drvdata(ptport);
struct synaptics_data *priv = psmouse->private;
@@ -577,8 +579,11 @@ static psmouse_ret_t synaptics_process_byte(struct psmouse *psmouse)
priv->pkt_type = synaptics_detect_pkt_type(psmouse);
if (SYN_CAP_PASS_THROUGH(priv->capabilities) && synaptics_is_pt_packet(psmouse->packet)) {
- if (psmouse->ps2dev.serio->child)
- synaptics_pass_pt_packet(psmouse->ps2dev.serio->child, psmouse->packet);
+ if (!list_empty(&psmouse->ps2dev.serio->children))
+ synaptics_pass_pt_packet(
+ list_first_entry(&psmouse->ps2dev.serio->children,
+ struct serio, child_list),
+ psmouse->packet);
} else
synaptics_process_packet(psmouse);
diff --git a/drivers/input/serio/serio.c b/drivers/input/serio/serio.c
index c3b626e..55c46e8 100644
--- a/drivers/input/serio/serio.c
+++ b/drivers/input/serio/serio.c
@@ -312,12 +312,9 @@ static void serio_handle_event(void)
* 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)
+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) {
@@ -325,38 +322,41 @@ static void serio_remove_pending_events(void *object)
serio_free_event(event);
}
}
+}
+
+static void serio_remove_pending_events(void *object)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&serio_event_lock, flags);
+
+ __serio_remove_pending_events(object);
spin_unlock_irqrestore(&serio_event_lock, flags);
}
/*
* Destroy 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.
*/
-static struct serio *serio_get_pending_child(struct serio *parent)
+static void serio_drop_pending_children(struct serio *parent)
{
- struct serio_event *event;
- struct serio *serio, *child = NULL;
+ struct serio_event *event, *temp;
+ struct serio *serio;
unsigned long flags;
spin_lock_irqsave(&serio_event_lock, flags);
- list_for_each_entry(event, &serio_event_list, node) {
+ list_for_each_entry_safe(event, temp, &serio_event_list, node) {
if (event->type == SERIO_REGISTER_PORT) {
serio = event->object;
if (serio->parent == parent) {
- child = serio;
- break;
+ __serio_remove_pending_events(serio);
+ put_device(&serio->dev);
}
}
}
spin_unlock_irqrestore(&serio_event_lock, flags);
- return child;
}
static int serio_thread(void *nothing)
@@ -516,6 +516,9 @@ static void serio_init_port(struct serio *serio)
__module_get(THIS_MODULE);
INIT_LIST_HEAD(&serio->node);
+ INIT_LIST_HEAD(&serio->children);
+ INIT_LIST_HEAD(&serio->child_list);
+ INIT_LIST_HEAD(&serio->internal);
spin_lock_init(&serio->lock);
mutex_init(&serio->drv_mutex);
device_initialize(&serio->dev);
@@ -542,7 +545,7 @@ static void serio_add_port(struct serio *serio)
if (serio->parent) {
serio_pause_rx(serio->parent);
- serio->parent->child = serio;
+ list_add_tail(&serio->child_list, &serio->parent->children);
serio_continue_rx(serio->parent);
}
@@ -564,20 +567,14 @@ static void serio_add_port(struct serio *serio)
*/
static void serio_destroy_port(struct serio *serio)
{
- struct serio *child;
-
- child = serio_get_pending_child(serio);
- if (child) {
- serio_remove_pending_events(child);
- put_device(&child->dev);
- }
+ serio_drop_pending_children(serio);
if (serio->stop)
serio->stop(serio);
if (serio->parent) {
serio_pause_rx(serio->parent);
- serio->parent->child = NULL;
+ list_del(&serio->child_list);
serio_continue_rx(serio->parent);
serio->parent = NULL;
}
@@ -613,13 +610,19 @@ static int serio_reconnect_port(struct serio *serio)
*/
static void serio_reconnect_chain(struct serio *serio)
{
- do {
- if (serio_reconnect_port(serio)) {
- /* Ok, old children are now gone, we are done */
- break;
- }
- serio = serio->child;
- } while (serio);
+ struct serio *child;
+ LIST_HEAD(todo);
+
+ list_add_tail(&serio->internal, &todo);
+
+ while (!list_empty(&todo)) {
+ serio = list_first_entry(&todo, struct serio, internal);
+ list_del_init(&serio->internal);
+
+ if (!serio_reconnect_port(serio))
+ list_for_each_entry(child, &serio->children, child_list)
+ list_add_tail(&child->internal, &todo);
+ }
}
/*
@@ -628,29 +631,31 @@ static void serio_reconnect_chain(struct serio *serio)
*/
static void serio_disconnect_port(struct serio *serio)
{
- struct serio *s, *parent;
+ struct serio *s, *child;
+ LIST_HEAD(todo);
- if (serio->child) {
- /*
- * Children ports should be disconnected and destroyed
- * first, staring with the leaf one, since we don't want
- * to do recursion
- */
- for (s = serio; s->child; s = s->child)
- /* empty */;
+ list_add_tail(&serio->internal, &todo);
- do {
- parent = s->parent;
+ while (!list_empty(&todo)) {
+ s = list_first_entry(&todo, struct serio, internal);
+
+ if (!list_empty(&s->children)) {
+ list_for_each_entry(child, &s->children, child_list)
+ list_add(&child->internal, &todo);
+
+ /*
+ * We will return to this item later, when it will have
+ * no children.
+ */
+ } else {
+ list_del_init(&s->internal);
device_release_driver(&s->dev);
- serio_destroy_port(s);
- } while ((s = parent) != serio);
- }
- /*
- * Ok, no children left, now disconnect this port
- */
- device_release_driver(&serio->dev);
+ if (s != serio)
+ serio_destroy_port(s);
+ }
+ }
}
void serio_rescan(struct serio *serio)
@@ -689,14 +694,15 @@ void serio_unregister_port(struct serio *serio)
EXPORT_SYMBOL(serio_unregister_port);
/*
- * Safely unregisters child port if one is present.
+ * Safely unregisters child ports if any is present.
*/
void serio_unregister_child_port(struct serio *serio)
{
+ struct serio *s, *temp;
mutex_lock(&serio_mutex);
- if (serio->child) {
- serio_disconnect_port(serio->child);
- serio_destroy_port(serio->child);
+ list_for_each_entry_safe(s, temp, &serio->children, child_list) {
+ 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 b555256..861a72a 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_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 */
@@ -50,6 +52,7 @@ struct serio {
struct device dev;
struct list_head node;
+ struct list_head internal; /* Used internally to avoid recursion */
};
#define to_serio_port(d) container_of(d, struct serio, dev)
--
1.7.1
--
To unsubscribe from this list: send the line "unsubscribe linux-input" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
