diff options
Diffstat (limited to 'drivers/usb/gadget/udc-core.c')
-rw-r--r-- | drivers/usb/gadget/udc-core.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/drivers/usb/gadget/udc-core.c b/drivers/usb/gadget/udc-core.c new file mode 100644 index 0000000000..fc931aa971 --- /dev/null +++ b/drivers/usb/gadget/udc-core.c @@ -0,0 +1,357 @@ +/** + * 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/>. + */ +#define VERBOSE_DEBUG +#include <common.h> +#include <driver.h> +#include <init.h> +#include <usb/ch9.h> +#include <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_d dev; + struct list_head list; +}; + +static LIST_HEAD(udc_list); + +/* ------------------------------------------------------------------------- */ + +#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 */ + +/* ------------------------------------------------------------------------- */ + +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_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_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_d *parent, struct usb_gadget *gadget, + void (*release)(struct device_d *dev)) +{ + struct usb_udc *udc; + int ret = -ENOMEM; + + udc = kzalloc(sizeof(*udc), GFP_KERNEL); + if (!udc) + goto err1; + + strcpy(gadget->dev.name, "gadget"); + gadget->dev.id = DEVICE_ID_DYNAMIC; + gadget->dev.parent = parent; + + ret = register_device(&gadget->dev); + if (ret) + goto err2; + + strcpy(udc->dev.name, "udc"); + udc->dev.id = DEVICE_ID_DYNAMIC; + + udc->gadget = gadget; + + list_add_tail(&udc->list, &udc_list); + + register_device(&udc->dev); + + usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); + + return 0; +err2: + 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_d *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); + + 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; + + list_for_each_entry(udc, &udc_list, list) + if (udc->gadget == gadget) + goto found; + + dev_err(gadget->dev.parent, "gadget not registered.\n"); + + return; + +found: + dev_vdbg(gadget->dev.parent, "unregistering gadget\n"); + + list_del(&udc->list); + + if (udc->driver) + usb_gadget_remove_driver(udc); + + unregister_device(&udc->dev); + unregister_device(&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); + + 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; + + 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: + 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; + + 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"); + + return -ENODEV; +found: + ret = udc_bind_to_driver(udc, driver); + + 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; + + list_for_each_entry(udc, &udc_list, list) + if (udc->driver == driver) { + usb_gadget_remove_driver(udc); + ret = 0; + break; + } + + return ret; +} +EXPORT_SYMBOL_GPL(usb_gadget_unregister_driver); |