diff options
Diffstat (limited to 'drivers/usb/common/roles.c')
-rw-r--r-- | drivers/usb/common/roles.c | 314 |
1 files changed, 0 insertions, 314 deletions
diff --git a/drivers/usb/common/roles.c b/drivers/usb/common/roles.c deleted file mode 100644 index 99116af07f1d..000000000000 --- a/drivers/usb/common/roles.c +++ /dev/null @@ -1,314 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * USB Role Switch Support - * - * Copyright (C) 2018 Intel Corporation - * Author: Heikki Krogerus <heikki.krogerus@linux.intel.com> - * Hans de Goede <hdegoede@redhat.com> - */ - -#include <linux/usb/role.h> -#include <linux/device.h> -#include <linux/module.h> -#include <linux/mutex.h> -#include <linux/slab.h> - -static struct class *role_class; - -struct usb_role_switch { - struct device dev; - struct mutex lock; /* device lock*/ - enum usb_role role; - - /* From descriptor */ - struct device *usb2_port; - struct device *usb3_port; - struct device *udc; - usb_role_switch_set_t set; - usb_role_switch_get_t get; - bool allow_userspace_control; -}; - -#define to_role_switch(d) container_of(d, struct usb_role_switch, dev) - -/** - * usb_role_switch_set_role - Set USB role for a switch - * @sw: USB role switch - * @role: USB role to be switched to - * - * Set USB role @role for @sw. - */ -int usb_role_switch_set_role(struct usb_role_switch *sw, enum usb_role role) -{ - int ret; - - if (IS_ERR_OR_NULL(sw)) - return 0; - - mutex_lock(&sw->lock); - - ret = sw->set(sw->dev.parent, role); - if (!ret) - sw->role = role; - - mutex_unlock(&sw->lock); - - return ret; -} -EXPORT_SYMBOL_GPL(usb_role_switch_set_role); - -/** - * usb_role_switch_get_role - Get the USB role for a switch - * @sw: USB role switch - * - * Depending on the role-switch-driver this function returns either a cached - * value of the last set role, or reads back the actual value from the hardware. - */ -enum usb_role usb_role_switch_get_role(struct usb_role_switch *sw) -{ - enum usb_role role; - - if (IS_ERR_OR_NULL(sw)) - return USB_ROLE_NONE; - - mutex_lock(&sw->lock); - - if (sw->get) - role = sw->get(sw->dev.parent); - else - role = sw->role; - - mutex_unlock(&sw->lock); - - return role; -} -EXPORT_SYMBOL_GPL(usb_role_switch_get_role); - -static int __switch_match(struct device *dev, const void *name) -{ - return !strcmp((const char *)name, dev_name(dev)); -} - -static void *usb_role_switch_match(struct device_connection *con, int ep, - void *data) -{ - struct device *dev; - - dev = class_find_device(role_class, NULL, con->endpoint[ep], - __switch_match); - - return dev ? to_role_switch(dev) : ERR_PTR(-EPROBE_DEFER); -} - -/** - * usb_role_switch_get - Find USB role switch linked with the caller - * @dev: The caller device - * - * Finds and returns role switch linked with @dev. The reference count for the - * found switch is incremented. - */ -struct usb_role_switch *usb_role_switch_get(struct device *dev) -{ - struct usb_role_switch *sw; - - sw = device_connection_find_match(dev, "usb-role-switch", NULL, - usb_role_switch_match); - - if (!IS_ERR_OR_NULL(sw)) - WARN_ON(!try_module_get(sw->dev.parent->driver->owner)); - - return sw; -} -EXPORT_SYMBOL_GPL(usb_role_switch_get); - -/** - * usb_role_switch_put - Release handle to a switch - * @sw: USB Role Switch - * - * Decrement reference count for @sw. - */ -void usb_role_switch_put(struct usb_role_switch *sw) -{ - if (!IS_ERR_OR_NULL(sw)) { - put_device(&sw->dev); - module_put(sw->dev.parent->driver->owner); - } -} -EXPORT_SYMBOL_GPL(usb_role_switch_put); - -static umode_t -usb_role_switch_is_visible(struct kobject *kobj, struct attribute *attr, int n) -{ - struct device *dev = container_of(kobj, typeof(*dev), kobj); - struct usb_role_switch *sw = to_role_switch(dev); - - if (sw->allow_userspace_control) - return attr->mode; - - return 0; -} - -static const char * const usb_roles[] = { - [USB_ROLE_NONE] = "none", - [USB_ROLE_HOST] = "host", - [USB_ROLE_DEVICE] = "device", -}; - -static ssize_t -role_show(struct device *dev, struct device_attribute *attr, char *buf) -{ - struct usb_role_switch *sw = to_role_switch(dev); - enum usb_role role = usb_role_switch_get_role(sw); - - return sprintf(buf, "%s\n", usb_roles[role]); -} - -static ssize_t role_store(struct device *dev, struct device_attribute *attr, - const char *buf, size_t size) -{ - struct usb_role_switch *sw = to_role_switch(dev); - int ret; - - ret = sysfs_match_string(usb_roles, buf); - if (ret < 0) { - bool res; - - /* Extra check if the user wants to disable the switch */ - ret = kstrtobool(buf, &res); - if (ret || res) - return -EINVAL; - } - - ret = usb_role_switch_set_role(sw, ret); - if (ret) - return ret; - - return size; -} -static DEVICE_ATTR_RW(role); - -static struct attribute *usb_role_switch_attrs[] = { - &dev_attr_role.attr, - NULL, -}; - -static const struct attribute_group usb_role_switch_group = { - .is_visible = usb_role_switch_is_visible, - .attrs = usb_role_switch_attrs, -}; - -static const struct attribute_group *usb_role_switch_groups[] = { - &usb_role_switch_group, - NULL, -}; - -static int -usb_role_switch_uevent(struct device *dev, struct kobj_uevent_env *env) -{ - int ret; - - ret = add_uevent_var(env, "USB_ROLE_SWITCH=%s", dev_name(dev)); - if (ret) - dev_err(dev, "failed to add uevent USB_ROLE_SWITCH\n"); - - return ret; -} - -static void usb_role_switch_release(struct device *dev) -{ - struct usb_role_switch *sw = to_role_switch(dev); - - kfree(sw); -} - -static const struct device_type usb_role_dev_type = { - .name = "usb_role_switch", - .groups = usb_role_switch_groups, - .uevent = usb_role_switch_uevent, - .release = usb_role_switch_release, -}; - -/** - * usb_role_switch_register - Register USB Role Switch - * @parent: Parent device for the switch - * @desc: Description of the switch - * - * USB Role Switch is a device capable or choosing the role for USB connector. - * On platforms where the USB controller is dual-role capable, the controller - * driver will need to register the switch. On platforms where the USB host and - * USB device controllers behind the connector are separate, there will be a - * mux, and the driver for that mux will need to register the switch. - * - * Returns handle to a new role switch or ERR_PTR. The content of @desc is - * copied. - */ -struct usb_role_switch * -usb_role_switch_register(struct device *parent, - const struct usb_role_switch_desc *desc) -{ - struct usb_role_switch *sw; - int ret; - - if (!desc || !desc->set) - return ERR_PTR(-EINVAL); - - sw = kzalloc(sizeof(*sw), GFP_KERNEL); - if (!sw) - return ERR_PTR(-ENOMEM); - - mutex_init(&sw->lock); - - sw->allow_userspace_control = desc->allow_userspace_control; - sw->usb2_port = desc->usb2_port; - sw->usb3_port = desc->usb3_port; - sw->udc = desc->udc; - sw->set = desc->set; - sw->get = desc->get; - - sw->dev.parent = parent; - sw->dev.class = role_class; - sw->dev.type = &usb_role_dev_type; - dev_set_name(&sw->dev, "%s-role-switch", dev_name(parent)); - - ret = device_register(&sw->dev); - if (ret) { - put_device(&sw->dev); - return ERR_PTR(ret); - } - - /* TODO: Symlinks for the host port and the device controller. */ - - return sw; -} -EXPORT_SYMBOL_GPL(usb_role_switch_register); - -/** - * usb_role_switch_unregister - Unregsiter USB Role Switch - * @sw: USB Role Switch - * - * Unregister switch that was registered with usb_role_switch_register(). - */ -void usb_role_switch_unregister(struct usb_role_switch *sw) -{ - if (!IS_ERR_OR_NULL(sw)) - device_unregister(&sw->dev); -} -EXPORT_SYMBOL_GPL(usb_role_switch_unregister); - -static int __init usb_roles_init(void) -{ - role_class = class_create(THIS_MODULE, "usb_role"); - return PTR_ERR_OR_ZERO(role_class); -} -subsys_initcall(usb_roles_init); - -static void __exit usb_roles_exit(void) -{ - class_destroy(role_class); -} -module_exit(usb_roles_exit); - -MODULE_AUTHOR("Heikki Krogerus <heikki.krogerus@linux.intel.com>"); -MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>"); -MODULE_LICENSE("GPL v2"); -MODULE_DESCRIPTION("USB Role Class"); |