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path: root/drivers/usb/roles/class.c
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Diffstat (limited to 'drivers/usb/roles/class.c')
-rw-r--r--drivers/usb/roles/class.c74
1 files changed, 64 insertions, 10 deletions
diff --git a/drivers/usb/roles/class.c b/drivers/usb/roles/class.c
index ae41578bd014..30482d4cf826 100644
--- a/drivers/usb/roles/class.c
+++ b/drivers/usb/roles/class.c
@@ -7,9 +7,11 @@
* Hans de Goede <hdegoede@redhat.com>
*/
+#include <linux/component.h>
#include <linux/usb/role.h>
#include <linux/property.h>
#include <linux/device.h>
+#include <linux/lockdep.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/slab.h>
@@ -20,8 +22,11 @@ static const struct class role_class = {
struct usb_role_switch {
struct device dev;
+ struct lock_class_key key;
struct mutex lock; /* device lock*/
+ struct module *module; /* the module this device depends on */
enum usb_role role;
+ bool registered;
/* From descriptor */
struct device *usb2_port;
@@ -34,6 +39,32 @@ struct usb_role_switch {
#define to_role_switch(d) container_of(d, struct usb_role_switch, dev)
+static int connector_bind(struct device *dev, struct device *connector, void *data)
+{
+ int ret;
+
+ ret = sysfs_create_link(&dev->kobj, &connector->kobj, "connector");
+ if (ret)
+ return ret;
+
+ ret = sysfs_create_link(&connector->kobj, &dev->kobj, "usb-role-switch");
+ if (ret)
+ sysfs_remove_link(&dev->kobj, "connector");
+
+ return ret;
+}
+
+static void connector_unbind(struct device *dev, struct device *connector, void *data)
+{
+ sysfs_remove_link(&connector->kobj, "usb-role-switch");
+ sysfs_remove_link(&dev->kobj, "connector");
+}
+
+static const struct component_ops connector_ops = {
+ .bind = connector_bind,
+ .unbind = connector_unbind,
+};
+
/**
* usb_role_switch_set_role - Set USB role for a switch
* @sw: USB role switch
@@ -48,6 +79,9 @@ int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role)
if (IS_ERR_OR_NULL(sw))
return 0;
+ if (!sw->registered)
+ return -EOPNOTSUPP;
+
mutex_lock(&sw->lock);
ret = sw->set(sw, role);
@@ -73,7 +107,7 @@ enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw)
{
enum usb_role role;
- if (IS_ERR_OR_NULL(sw))
+ if (IS_ERR_OR_NULL(sw) || !sw->registered)
return USB_ROLE_NONE;
mutex_lock(&sw->lock);
@@ -135,7 +169,7 @@ struct usb_role_switch *usb_role_switch_get(struct device *dev)
usb_role_switch_match);
if (!IS_ERR_OR_NULL(sw))
- WARN_ON(!try_module_get(sw->dev.parent->driver->owner));
+ WARN_ON(!try_module_get(sw->module));
return sw;
}
@@ -157,7 +191,7 @@ struct usb_role_switch *fwnode_usb_role_switch_get(struct fwnode_handle *fwnode)
sw = fwnode_connection_find_match(fwnode, "usb-role-switch",
NULL, usb_role_switch_match);
if (!IS_ERR_OR_NULL(sw))
- WARN_ON(!try_module_get(sw->dev.parent->driver->owner));
+ WARN_ON(!try_module_get(sw->module));
return sw;
}
@@ -172,7 +206,7 @@ EXPORT_SYMBOL_GPL(fwnode_usb_role_switch_get);
void usb_role_switch_put(struct usb_role_switch *sw)
{
if (!IS_ERR_OR_NULL(sw)) {
- module_put(sw->dev.parent->driver->owner);
+ module_put(sw->module);
put_device(&sw->dev);
}
}
@@ -189,15 +223,18 @@ struct usb_role_switch *
usb_role_switch_find_by_fwnode(const struct fwnode_handle *fwnode)
{
struct device *dev;
+ struct usb_role_switch *sw = NULL;
if (!fwnode)
return NULL;
dev = class_find_device_by_fwnode(&role_class, fwnode);
- if (dev)
- WARN_ON(!try_module_get(dev->parent->driver->owner));
+ if (dev) {
+ sw = to_role_switch(dev);
+ WARN_ON(!try_module_get(sw->module));
+ }
- return dev ? to_role_switch(dev) : NULL;
+ return sw;
}
EXPORT_SYMBOL_GPL(usb_role_switch_find_by_fwnode);
@@ -291,6 +328,8 @@ static void usb_role_switch_release(struct device *dev)
{
struct usb_role_switch *sw = to_role_switch(dev);
+ mutex_destroy(&sw->lock);
+ lockdep_unregister_key(&sw->key);
kfree(sw);
}
@@ -329,7 +368,8 @@ usb_role_switch_register(struct device *parent,
if (!sw)
return ERR_PTR(-ENOMEM);
- mutex_init(&sw->lock);
+ lockdep_register_key(&sw->key);
+ mutex_init_with_key(&sw->lock, &sw->key);
sw->allow_userspace_control = desc->allow_userspace_control;
sw->usb2_port = desc->usb2_port;
@@ -338,6 +378,7 @@ usb_role_switch_register(struct device *parent,
sw->set = desc->set;
sw->get = desc->get;
+ sw->module = parent->driver->owner;
sw->dev.parent = parent;
sw->dev.fwnode = desc->fwnode;
sw->dev.class = &role_class;
@@ -346,12 +387,21 @@ usb_role_switch_register(struct device *parent,
dev_set_name(&sw->dev, "%s-role-switch",
desc->name ? desc->name : dev_name(parent));
+ sw->registered = true;
+
ret = device_register(&sw->dev);
if (ret) {
+ sw->registered = false;
put_device(&sw->dev);
return ERR_PTR(ret);
}
+ if (dev_fwnode(&sw->dev)) {
+ ret = component_add(&sw->dev, &connector_ops);
+ if (ret)
+ dev_warn(&sw->dev, "failed to add component\n");
+ }
+
/* TODO: Symlinks for the host port and the device controller. */
return sw;
@@ -366,8 +416,12 @@ EXPORT_SYMBOL_GPL(usb_role_switch_register);
*/
void usb_role_switch_unregister(struct usb_role_switch *sw)
{
- if (!IS_ERR_OR_NULL(sw))
- device_unregister(&sw->dev);
+ if (IS_ERR_OR_NULL(sw))
+ return;
+ sw->registered = false;
+ if (dev_fwnode(&sw->dev))
+ component_del(&sw->dev, &connector_ops);
+ device_unregister(&sw->dev);
}
EXPORT_SYMBOL_GPL(usb_role_switch_unregister);