| /** |
| * 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/dma-mapping.h> |
| #include <linux/workqueue.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 LIST_HEAD(udc_list); |
| static DEFINE_MUTEX(udc_lock); |
| |
| /* ------------------------------------------------------------------------- */ |
| |
| #ifdef CONFIG_HAS_DMA |
| |
| int usb_gadget_map_request(struct usb_gadget *gadget, |
| struct usb_request *req, int is_in) |
| { |
| if (req->length == 0) |
| return 0; |
| |
| if (req->num_sgs) { |
| int mapped; |
| |
| mapped = dma_map_sg(&gadget->dev, req->sg, req->num_sgs, |
| is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); |
| if (mapped == 0) { |
| dev_err(&gadget->dev, "failed to map SGs\n"); |
| return -EFAULT; |
| } |
| |
| req->num_mapped_sgs = mapped; |
| } else { |
| req->dma = dma_map_single(&gadget->dev, req->buf, req->length, |
| is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); |
| |
| if (dma_mapping_error(&gadget->dev, req->dma)) { |
| dev_err(&gadget->dev, "failed to map buffer\n"); |
| return -EFAULT; |
| } |
| } |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(usb_gadget_map_request); |
| |
| void usb_gadget_unmap_request(struct usb_gadget *gadget, |
| struct usb_request *req, int is_in) |
| { |
| if (req->length == 0) |
| return; |
| |
| if (req->num_mapped_sgs) { |
| dma_unmap_sg(&gadget->dev, req->sg, req->num_mapped_sgs, |
| is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); |
| |
| req->num_mapped_sgs = 0; |
| } else { |
| dma_unmap_single(&gadget->dev, req->dma, req->length, |
| is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); |
| } |
| } |
| EXPORT_SYMBOL_GPL(usb_gadget_unmap_request); |
| |
| #endif /* CONFIG_HAS_DMA */ |
| |
| /* ------------------------------------------------------------------------- */ |
| |
| /** |
| * usb_gadget_giveback_request - give the request back to the gadget layer |
| * Context: in_interrupt() |
| * |
| * This is called by device controller drivers in order to return the |
| * completed request back to the gadget layer. |
| */ |
| void usb_gadget_giveback_request(struct usb_ep *ep, |
| struct usb_request *req) |
| { |
| req->complete(ep, req); |
| } |
| EXPORT_SYMBOL_GPL(usb_gadget_giveback_request); |
| |
| /* ------------------------------------------------------------------------- */ |
| |
| static void usb_gadget_state_work(struct work_struct *work) |
| { |
| struct usb_gadget *gadget = work_to_gadget(work); |
| struct usb_udc *udc = NULL; |
| |
| mutex_lock(&udc_lock); |
| list_for_each_entry(udc, &udc_list, list) |
| if (udc->gadget == gadget) |
| goto found; |
| mutex_unlock(&udc_lock); |
| |
| return; |
| |
| found: |
| mutex_unlock(&udc_lock); |
| |
| sysfs_notify(&udc->dev.kobj, NULL, "state"); |
| } |
| |
| void usb_gadget_set_state(struct usb_gadget *gadget, |
| enum usb_device_state state) |
| { |
| gadget->state = state; |
| schedule_work(&gadget->work); |
| } |
| EXPORT_SYMBOL_GPL(usb_gadget_set_state); |
| |
| /* ------------------------------------------------------------------------- */ |
| |
| /** |
| * usb_gadget_udc_reset - notifies the udc core that bus reset occurs |
| * @gadget: The gadget which bus reset occurs |
| * @driver: The gadget driver we want to notify |
| * |
| * If the udc driver has bus reset handler, it needs to call this when the bus |
| * reset occurs, it notifies the gadget driver that the bus reset occurs as |
| * well as updates gadget state. |
| */ |
| void usb_gadget_udc_reset(struct usb_gadget *gadget, |
| struct usb_gadget_driver *driver) |
| { |
| driver->reset(gadget); |
| usb_gadget_set_state(gadget, USB_STATE_DEFAULT); |
| } |
| EXPORT_SYMBOL_GPL(usb_gadget_udc_reset); |
| |
| /** |
| * usb_gadget_udc_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 |
| * |
| * 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_udc_start(struct usb_gadget *gadget, |
| struct usb_gadget_driver *driver) |
| { |
| return gadget->ops->udc_start(gadget, driver); |
| } |
| |
| /** |
| * usb_gadget_udc_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_udc_stop(struct usb_gadget *gadget, |
| struct usb_gadget_driver *driver) |
| { |
| gadget->ops->udc_stop(gadget, 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); |
| } |
| |
| static const struct attribute_group *usb_udc_attr_groups[]; |
| |
| static void usb_udc_nop_release(struct device *dev) |
| { |
| dev_vdbg(dev, "%s\n", __func__); |
| } |
| |
| /** |
| * usb_add_gadget_udc_release - 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. |
| * @release: a gadget release function. |
| * |
| * Returns zero on success, negative errno otherwise. |
| */ |
| int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, |
| void (*release)(struct device *dev)) |
| { |
| struct usb_udc *udc; |
| int ret = -ENOMEM; |
| |
| udc = kzalloc(sizeof(*udc), GFP_KERNEL); |
| if (!udc) |
| goto err1; |
| |
| dev_set_name(&gadget->dev, "gadget"); |
| INIT_WORK(&gadget->work, usb_gadget_state_work); |
| gadget->dev.parent = parent; |
| |
| #ifdef CONFIG_HAS_DMA |
| dma_set_coherent_mask(&gadget->dev, parent->coherent_dma_mask); |
| gadget->dev.dma_parms = parent->dma_parms; |
| gadget->dev.dma_mask = parent->dma_mask; |
| #endif |
| |
| if (release) |
| gadget->dev.release = release; |
| else |
| gadget->dev.release = usb_udc_nop_release; |
| |
| ret = device_register(&gadget->dev); |
| if (ret) |
| goto err2; |
| |
| device_initialize(&udc->dev); |
| udc->dev.release = usb_udc_release; |
| udc->dev.class = udc_class; |
| udc->dev.groups = usb_udc_attr_groups; |
| udc->dev.parent = parent; |
| ret = dev_set_name(&udc->dev, "%s", kobject_name(&parent->kobj)); |
| if (ret) |
| goto err3; |
| |
| udc->gadget = gadget; |
| |
| mutex_lock(&udc_lock); |
| list_add_tail(&udc->list, &udc_list); |
| |
| ret = device_add(&udc->dev); |
| if (ret) |
| goto err4; |
| |
| usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); |
| |
| mutex_unlock(&udc_lock); |
| |
| return 0; |
| |
| err4: |
| list_del(&udc->list); |
| mutex_unlock(&udc_lock); |
| |
| err3: |
| put_device(&udc->dev); |
| |
| err2: |
| put_device(&gadget->dev); |
| kfree(udc); |
| |
| err1: |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(usb_add_gadget_udc_release); |
| |
| /** |
| * 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) |
| { |
| return usb_add_gadget_udc_release(parent, gadget, NULL); |
| } |
| 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_disconnect(udc->gadget); |
| udc->driver->disconnect(udc->gadget); |
| udc->driver->unbind(udc->gadget); |
| usb_gadget_udc_stop(udc->gadget, NULL); |
| |
| udc->driver = NULL; |
| udc->dev.driver = NULL; |
| udc->gadget->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); |
| flush_work(&gadget->work); |
| device_unregister(&udc->dev); |
| device_unregister(&gadget->dev); |
| } |
| EXPORT_SYMBOL_GPL(usb_del_gadget_udc); |
| |
| /* ------------------------------------------------------------------------- */ |
| |
| static int udc_bind_to_driver(struct usb_udc *udc, struct usb_gadget_driver *driver) |
| { |
| int ret; |
| |
| dev_dbg(&udc->dev, "registering UDC driver [%s]\n", |
| driver->function); |
| |
| udc->driver = driver; |
| udc->dev.driver = &driver->driver; |
| udc->gadget->dev.driver = &driver->driver; |
| |
| ret = driver->bind(udc->gadget, driver); |
| if (ret) |
| goto err1; |
| ret = usb_gadget_udc_start(udc->gadget, driver); |
| if (ret) { |
| driver->unbind(udc->gadget); |
| goto err1; |
| } |
| usb_gadget_connect(udc->gadget); |
| |
| kobject_uevent(&udc->dev.kobj, KOBJ_CHANGE); |
| return 0; |
| err1: |
| if (ret != -EISNAM) |
| dev_err(&udc->dev, "failed to start %s: %d\n", |
| udc->driver->function, ret); |
| udc->driver = NULL; |
| udc->dev.driver = NULL; |
| udc->gadget->dev.driver = NULL; |
| return ret; |
| } |
| |
| int udc_attach_driver(const char *name, struct usb_gadget_driver *driver) |
| { |
| struct usb_udc *udc = NULL; |
| int ret = -ENODEV; |
| |
| mutex_lock(&udc_lock); |
| list_for_each_entry(udc, &udc_list, list) { |
| ret = strcmp(name, dev_name(&udc->dev)); |
| if (!ret) |
| break; |
| } |
| if (ret) { |
| ret = -ENODEV; |
| goto out; |
| } |
| if (udc->driver) { |
| ret = -EBUSY; |
| goto out; |
| } |
| ret = udc_bind_to_driver(udc, driver); |
| out: |
| mutex_unlock(&udc_lock); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(udc_attach_driver); |
| |
| int usb_gadget_probe_driver(struct usb_gadget_driver *driver) |
| { |
| struct usb_udc *udc = NULL; |
| int ret; |
| |
| if (!driver || !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: |
| ret = udc_bind_to_driver(udc, driver); |
| 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); |
| usb_gadget_set_state(udc->gadget, |
| USB_STATE_NOTATTACHED); |
| 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 = container_of(dev, struct usb_udc, 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 = container_of(dev, struct usb_udc, dev); |
| |
| if (sysfs_streq(buf, "connect")) { |
| usb_gadget_udc_start(udc->gadget, udc->driver); |
| usb_gadget_connect(udc->gadget); |
| } else if (sysfs_streq(buf, "disconnect")) { |
| usb_gadget_disconnect(udc->gadget); |
| usb_gadget_udc_stop(udc->gadget, udc->driver); |
| } 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 state_show(struct device *dev, struct device_attribute *attr, |
| char *buf) |
| { |
| struct usb_udc *udc = container_of(dev, struct usb_udc, dev); |
| struct usb_gadget *gadget = udc->gadget; |
| |
| return sprintf(buf, "%s\n", usb_state_string(gadget->state)); |
| } |
| static DEVICE_ATTR_RO(state); |
| |
| #define USB_UDC_SPEED_ATTR(name, param) \ |
| ssize_t name##_show(struct device *dev, \ |
| struct device_attribute *attr, char *buf) \ |
| { \ |
| struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \ |
| return snprintf(buf, PAGE_SIZE, "%s\n", \ |
| usb_speed_string(udc->gadget->param)); \ |
| } \ |
| static DEVICE_ATTR_RO(name) |
| |
| static USB_UDC_SPEED_ATTR(current_speed, speed); |
| static USB_UDC_SPEED_ATTR(maximum_speed, max_speed); |
| |
| #define USB_UDC_ATTR(name) \ |
| ssize_t name##_show(struct device *dev, \ |
| struct device_attribute *attr, char *buf) \ |
| { \ |
| struct usb_udc *udc = container_of(dev, struct usb_udc, dev); \ |
| struct usb_gadget *gadget = udc->gadget; \ |
| \ |
| return snprintf(buf, PAGE_SIZE, "%d\n", gadget->name); \ |
| } \ |
| static DEVICE_ATTR_RO(name) |
| |
| 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_state.attr, |
| &dev_attr_current_speed.attr, |
| &dev_attr_maximum_speed.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; |
| 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"); |