diff options
Diffstat (limited to 'drivers/usb/gadget/udc/udc-core.c')
-rw-r--r-- | drivers/usb/gadget/udc/udc-core.c | 354 |
1 files changed, 354 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c new file mode 100644 index 0000000000..875e998a82 --- /dev/null +++ b/drivers/usb/gadget/udc/udc-core.c @@ -0,0 +1,354 @@ +/** + * udc-core.c - Core UDC Framework + * + * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com + * + * Author: Felipe Balbi <balbi@ti.com> + * + * Taken from Linux Kernel v3.19-rc1 (drivers/usb/gadget/udc-core.c) and ported + * to uboot. + * + * commit 02e8c96627 : usb: gadget: udc: core: prepend udc_attach_driver with + * usb_ + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <linux/compat.h> +#include <malloc.h> +#include <asm/cache.h> +#include <asm/dma-mapping.h> +#include <common.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); +DEFINE_MUTEX(udc_lock); + +/* ------------------------------------------------------------------------- */ + +int usb_gadget_map_request(struct usb_gadget *gadget, + struct usb_request *req, int is_in) +{ + if (req->length == 0) + return 0; + + req->dma = dma_map_single(req->buf, req->length, + is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + + 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; + + dma_unmap_single((void *)req->dma, req->length, + is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); +} +EXPORT_SYMBOL_GPL(usb_gadget_unmap_request); + +/* ------------------------------------------------------------------------- */ + +/** + * 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); + +/* ------------------------------------------------------------------------- */ + +void usb_gadget_set_state(struct usb_gadget *gadget, + enum usb_device_state state) +{ + gadget->state = state; +} +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 + * @udc: The UDC to be started + * + * 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_udc *udc) +{ + return udc->gadget->ops->udc_start(udc->gadget, udc->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_udc *udc) +{ + udc->gadget->ops->udc_stop(udc->gadget); +} + +/** + * 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); + kfree(udc); +} + +/** + * 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"); + gadget->dev.parent = parent; + + udc->dev.release = usb_udc_release; + udc->dev.class = udc_class; + udc->dev.parent = parent; + + udc->gadget = gadget; + + mutex_lock(&udc_lock); + list_add_tail(&udc->list, &udc_list); + + usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); + + mutex_unlock(&udc_lock); + + return 0; + +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->driver->function); + + usb_gadget_disconnect(udc->gadget); + udc->driver->disconnect(udc->gadget); + udc->driver->unbind(udc->gadget); + usb_gadget_udc_stop(udc); + + udc->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); +} +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; + + ret = driver->bind(udc->gadget); + if (ret) + goto err1; + ret = usb_gadget_udc_start(udc); + if (ret) { + driver->unbind(udc->gadget); + goto err1; + } + usb_gadget_connect(udc->gadget); + + return 0; +err1: + if (ret != -EISNAM) + dev_err(&udc->dev, "failed to start %s: %d\n", + udc->driver->function, ret); + udc->driver = NULL; + return ret; +} + +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; + } + + printf("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_register_driver(struct usb_gadget_driver *driver) +{ + return usb_gadget_probe_driver(driver); +} +EXPORT_SYMBOL_GPL(usb_gadget_register_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); + +MODULE_DESCRIPTION("UDC Framework"); +MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>"); +MODULE_LICENSE("GPL v2"); |