--- /dev/null
+/**
+ * udc.c - Core UDC Framework
+ *
+ * Copyright (C) 2010 Texas Instruments
+ * Author: Felipe Balbi <balbi@ti.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/err.h>
+
+#include <linux/usb/ch9.h>
+#include <linux/usb/gadget.h>
+
+/**
+ * struct usb_udc - describes one usb device controller
+ * @driver - the gadget driver pointer. For use by the class code
+ * @dev - the child device to the actual controller
+ * @gadget - the gadget. For use by the class code
+ * @list - for use by the udc class driver
+ *
+ * This represents the internal data structure which is used by the UDC-class
+ * to hold information about udc driver and gadget together.
+ */
+struct usb_udc {
+ struct usb_gadget_driver *driver;
+ struct usb_gadget *gadget;
+ struct device dev;
+ struct list_head list;
+};
+
+static struct class *udc_class;
+static struct device_type udc_device_type;
+static LIST_HEAD(udc_list);
+static DEFINE_MUTEX(udc_lock);
+
+/* ------------------------------------------------------------------------- */
+
+/**
+ * usb_gadget_start - tells usb device controller to start up
+ * @gadget: The gadget we want to get started
+ * @driver: The driver we want to bind to @gadget
+ * @bind: The bind function for @driver
+ *
+ * This call is issued by the UDC Class driver when it's about
+ * to register a gadget driver to the device controller, before
+ * calling gadget driver's bind() method.
+ *
+ * It allows the controller to be powered off until strictly
+ * necessary to have it powered on.
+ *
+ * Returns zero on success, else negative errno.
+ */
+static inline int usb_gadget_start(struct usb_gadget *gadget,
+ struct usb_gadget_driver *driver,
+ int (*bind)(struct usb_gadget *))
+{
+ return gadget->ops->start(driver, bind);
+}
+
+/**
+ * usb_gadget_stop - tells usb device controller we don't need it anymore
+ * @gadget: The device we want to stop activity
+ * @driver: The driver to unbind from @gadget
+ *
+ * This call is issued by the UDC Class driver after calling
+ * gadget driver's unbind() method.
+ *
+ * The details are implementation specific, but it can go as
+ * far as powering off UDC completely and disable its data
+ * line pullups.
+ */
+static inline void usb_gadget_stop(struct usb_gadget *gadget,
+ struct usb_gadget_driver *driver)
+{
+ gadget->ops->stop(driver);
+}
+
+/**
+ * usb_udc_release - release the usb_udc struct
+ * @dev: the dev member within usb_udc
+ *
+ * This is called by driver's core in order to free memory once the last
+ * reference is released.
+ */
+static void usb_udc_release(struct device *dev)
+{
+ struct usb_udc *udc;
+
+ udc = container_of(dev, struct usb_udc, dev);
+ dev_dbg(dev, "releasing '%s'\n", dev_name(dev));
+ kfree(udc);
+}
+
+/**
+ * usb_add_gadget_udc - adds a new gadget to the udc class driver list
+ * @parent: the parent device to this udc. Usually the controller
+ * driver's device.
+ * @gadget: the gadget to be added to the list
+ *
+ * Returns zero on success, negative errno otherwise.
+ */
+int usb_add_gadget_udc(struct device *parent, struct usb_gadget *gadget)
+{
+ struct usb_udc *udc;
+ int ret = -ENOMEM;
+
+ udc = kzalloc(sizeof(*udc), GFP_KERNEL);
+ if (!udc)
+ goto err1;
+
+ device_initialize(&udc->dev);
+ udc->dev.release = usb_udc_release;
+ udc->dev.class = udc_class;
+ udc->dev.parent = parent;
+ ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj));
+ if (ret)
+ goto err2;
+
+ udc->gadget = gadget;
+
+ mutex_lock(&udc_lock);
+ list_add_tail(&udc->list, &udc_list);
+
+ ret = device_add(&udc->dev);
+ if (ret)
+ goto err3;
+
+ mutex_unlock(&udc_lock);
+
+ return 0;
+err3:
+ list_del(&udc->list);
+ mutex_unlock(&udc_lock);
+
+err2:
+ put_device(&udc->dev);
+
+err1:
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usb_add_gadget_udc);
+
+static void usb_gadget_remove_driver(struct usb_udc *udc)
+{
+ dev_dbg(&udc->dev, "unregistering UDC driver [%s]\n",
+ udc->gadget->name);
+
+ kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
+
+ usb_gadget_stop(udc->gadget, udc->driver);
+
+ udc->driver = NULL;
+ udc->dev.driver = NULL;
+}
+
+/**
+ * usb_del_gadget_udc - deletes @udc from udc_list
+ * @gadget: the gadget to be removed.
+ *
+ * This, will call usb_gadget_unregister_driver() if
+ * the @udc is still busy.
+ */
+void usb_del_gadget_udc(struct usb_gadget *gadget)
+{
+ struct usb_udc *udc = NULL;
+
+ mutex_lock(&udc_lock);
+ list_for_each_entry(udc, &udc_list, list)
+ if (udc->gadget == gadget)
+ goto found;
+
+ dev_err(gadget->dev.parent, "gadget not registered.\n");
+ mutex_unlock(&udc_lock);
+
+ return;
+
+found:
+ dev_vdbg(gadget->dev.parent, "unregistering gadget\n");
+
+ list_del(&udc->list);
+ mutex_unlock(&udc_lock);
+
+ if (udc->driver)
+ usb_gadget_remove_driver(udc);
+
+ kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE);
+ device_unregister(&udc->dev);
+}
+EXPORT_SYMBOL_GPL(usb_del_gadget_udc);
+
+/* ------------------------------------------------------------------------- */
+
+int usb_gadget_probe_driver(struct usb_gadget_driver *driver,
+ int (*bind)(struct usb_gadget *))
+{
+ struct usb_udc *udc = NULL;
+ int ret;
+
+ if (!driver || !bind || !driver->setup)
+ return -EINVAL;
+
+ mutex_lock(&udc_lock);
+ list_for_each_entry(udc, &udc_list, list) {
+ /* For now we take the first one */
+ if (!udc->driver)
+ goto found;
+ }
+
+ pr_debug("couldn't find an available UDC\n");
+ mutex_unlock(&udc_lock);
+ return -ENODEV;
+
+found:
+ dev_dbg(&udc->dev, "registering UDC driver [%s]\n",
+ driver->function);
+
+ udc->driver = driver;
+ udc->dev.driver = &driver->driver;
+
+ ret = usb_gadget_start(udc->gadget, driver, bind);
+ if (ret)
+ goto err1;
+
+ kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE);
+ mutex_unlock(&udc_lock);
+ return 0;
+
+err1:
+ dev_err(&udc->dev, "failed to start %s: %d\n",
+ udc->driver->function, ret);
+ udc->driver = NULL;
+ udc->dev.driver = NULL;
+ mutex_unlock(&udc_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_probe_driver);
+
+int usb_gadget_unregister_driver(struct usb_gadget_driver *driver)
+{
+ struct usb_udc *udc = NULL;
+ int ret = -ENODEV;
+
+ if (!driver || !driver->unbind)
+ return -EINVAL;
+
+ mutex_lock(&udc_lock);
+ list_for_each_entry(udc, &udc_list, list)
+ if (udc->driver == driver) {
+ usb_gadget_remove_driver(udc);
+ ret = 0;
+ break;
+ }
+
+ mutex_unlock(&udc_lock);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver);
+
+/* ------------------------------------------------------------------------- */
+
+static ssize_t usb_udc_srp_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t n)
+{
+ struct usb_udc *udc = dev_get_drvdata(dev);
+
+ if (sysfs_streq(buf, "1"))
+ usb_gadget_wakeup(udc->gadget);
+
+ return n;
+}
+static DEVICE_ATTR(srp, S_IWUSR, NULL, usb_udc_srp_store);
+
+static ssize_t usb_udc_softconn_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t n)
+{
+ struct usb_udc *udc = dev_get_drvdata(dev);
+
+ if (sysfs_streq(buf, "connect")) {
+ usb_gadget_connect(udc->gadget);
+ } else if (sysfs_streq(buf, "disconnect")) {
+ usb_gadget_disconnect(udc->gadget);
+ } else {
+ dev_err(dev, "unsupported command '%s'\n", buf);
+ return -EINVAL;
+ }
+
+ return n;
+}
+static DEVICE_ATTR(soft_connect, S_IWUSR, NULL, usb_udc_softconn_store);
+
+static ssize_t usb_udc_speed_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct usb_udc *udc = dev_get_drvdata(dev);
+ struct usb_gadget *gadget = udc->gadget;
+
+ switch (gadget->speed) {
+ case USB_SPEED_LOW:
+ return snprintf(buf, PAGE_SIZE, "low-speed\n");
+ case USB_SPEED_FULL:
+ return snprintf(buf, PAGE_SIZE, "full-speed\n");
+ case USB_SPEED_HIGH:
+ return snprintf(buf, PAGE_SIZE, "high-speed\n");
+ case USB_SPEED_WIRELESS:
+ return snprintf(buf, PAGE_SIZE, "wireless\n");
+ case USB_SPEED_SUPER:
+ return snprintf(buf, PAGE_SIZE, "super-speed\n");
+ case USB_SPEED_UNKNOWN: /* FALLTHROUGH */
+ default:
+ return snprintf(buf, PAGE_SIZE, "UNKNOWN\n");
+ }
+}
+static DEVICE_ATTR(speed, S_IRUSR, usb_udc_speed_show, NULL);
+
+#define USB_UDC_ATTR(name) \
+ssize_t usb_udc_##name##_show(struct device *dev, \
+ struct device_attribute *attr, char *buf) \
+{ \
+ struct usb_udc *udc = dev_get_drvdata(dev); \
+ struct usb_gadget *gadget = udc->gadget; \
+ \
+ return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \
+} \
+static DEVICE_ATTR(name, S_IRUSR, usb_udc_##name##_show, NULL)
+
+static USB_UDC_ATTR(is_dualspeed);
+static USB_UDC_ATTR(is_otg);
+static USB_UDC_ATTR(is_a_peripheral);
+static USB_UDC_ATTR(b_hnp_enable);
+static USB_UDC_ATTR(a_hnp_support);
+static USB_UDC_ATTR(a_alt_hnp_support);
+
+static struct attribute *usb_udc_attrs[] = {
+ &dev_attr_srp.attr,
+ &dev_attr_soft_connect.attr,
+ &dev_attr_speed.attr,
+
+ &dev_attr_is_dualspeed.attr,
+ &dev_attr_is_otg.attr,
+ &dev_attr_is_a_peripheral.attr,
+ &dev_attr_b_hnp_enable.attr,
+ &dev_attr_a_hnp_support.attr,
+ &dev_attr_a_alt_hnp_support.attr,
+ NULL,
+};
+
+static const struct attribute_group usb_udc_attr_group = {
+ .attrs = usb_udc_attrs,
+};
+
+static const struct attribute_group *usb_udc_attr_groups[] = {
+ &usb_udc_attr_group,
+ NULL,
+};
+
+static int usb_udc_uevent(struct device *dev, struct kobj_uevent_env *env)
+{
+ struct usb_udc *udc = container_of(dev, struct usb_udc, dev);
+ int ret;
+
+ ret = add_uevent_var(env, "USB_UDC_NAME=%s", udc->gadget->name);
+ if (ret) {
+ dev_err(dev, "failed to add uevent USB_UDC_NAME\n");
+ return ret;
+ }
+
+ if (udc->driver) {
+ ret = add_uevent_var(env, "USB_UDC_DRIVER=%s",
+ udc->driver->function);
+ if (ret) {
+ dev_err(dev, "failed to add uevent USB_UDC_DRIVER\n");
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static int __init usb_udc_init(void)
+{
+ udc_class = class_create(THIS_MODULE, "udc");
+ if (IS_ERR(udc_class)) {
+ pr_err("failed to create udc class --> %ld\n",
+ PTR_ERR(udc_class));
+ return PTR_ERR(udc_class);
+ }
+
+ udc_class->dev_uevent = usb_udc_uevent;
+ udc_device_type.groups = usb_udc_attr_groups;
+
+ return 0;
+}
+subsys_initcall(usb_udc_init);
+
+static void __exit usb_udc_exit(void)
+{
+ class_destroy(udc_class);
+}
+module_exit(usb_udc_exit);
+
+MODULE_DESCRIPTION("UDC Framework");
+MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
+MODULE_LICENSE("GPL v2");
projects / mirror_ubuntu-zesty-kernel.git / commitdiff