diff options
| -rw-r--r-- | drivers/usb/gadget/udc/udc-core.c | 41 | ||||
| -rw-r--r-- | include/linux/usb/gadget.h | 2 |
2 files changed, 34 insertions, 9 deletions
diff --git a/drivers/usb/gadget/udc/udc-core.c b/drivers/usb/gadget/udc/udc-core.c index f76ebc8c1ed2..fd73a3ea07c2 100644 --- a/drivers/usb/gadget/udc/udc-core.c +++ b/drivers/usb/gadget/udc/udc-core.c @@ -51,8 +51,12 @@ struct usb_udc { static struct class *udc_class; static LIST_HEAD(udc_list); +static LIST_HEAD(gadget_driver_pending_list); static DEFINE_MUTEX(udc_lock); +static int udc_bind_to_driver(struct usb_udc *udc, + struct usb_gadget_driver *driver); + /* ------------------------------------------------------------------------- */ #ifdef CONFIG_HAS_DMA @@ -356,6 +360,7 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, void (*release)(struct device *dev)) { struct usb_udc *udc; + struct usb_gadget_driver *driver; int ret = -ENOMEM; udc = kzalloc(sizeof(*udc), GFP_KERNEL); @@ -403,6 +408,18 @@ int usb_add_gadget_udc_release(struct device *parent, struct usb_gadget *gadget, usb_gadget_set_state(gadget, USB_STATE_NOTATTACHED); udc->vbus = true; + /* pick up one of pending gadget drivers */ + list_for_each_entry(driver, &gadget_driver_pending_list, pending) { + if (!driver->udc_name || strcmp(driver->udc_name, + dev_name(&udc->dev)) == 0) { + ret = udc_bind_to_driver(udc, driver); + if (ret) + goto err4; + list_del(&driver->pending); + break; + } + } + mutex_unlock(&udc_lock); return 0; @@ -473,10 +490,14 @@ void usb_del_gadget_udc(struct usb_gadget *gadget) mutex_lock(&udc_lock); list_del(&udc->list); - mutex_unlock(&udc_lock); - if (udc->driver) + if (udc->driver) { + struct usb_gadget_driver *driver = udc->driver; + usb_gadget_remove_driver(udc); + list_add(&driver->pending, &gadget_driver_pending_list); + } + mutex_unlock(&udc_lock); kobject_uevent(&udc->dev.kobj, KOBJ_REMOVE); flush_work(&gadget->work); @@ -535,11 +556,7 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver) if (!ret) break; } - if (ret) - ret = -ENODEV; - else if (udc->driver) - ret = -EBUSY; - else + if (!ret && !udc->driver) goto found; } else { list_for_each_entry(udc, &udc_list, list) { @@ -549,9 +566,11 @@ int usb_gadget_probe_driver(struct usb_gadget_driver *driver) } } - pr_debug("couldn't find an available UDC\n"); + list_add_tail(&driver->pending, &gadget_driver_pending_list); + pr_info("udc-core: couldn't find an available UDC - added [%s] to list of pending drivers\n", + driver->function); mutex_unlock(&udc_lock); - return ret; + return 0; found: ret = udc_bind_to_driver(udc, driver); mutex_unlock(&udc_lock); @@ -577,6 +596,10 @@ int usb_gadget_unregister_driver(struct usb_gadget_driver *driver) break; } + if (ret) { + list_del(&driver->pending); + ret = 0; + } mutex_unlock(&udc_lock); return ret; } diff --git a/include/linux/usb/gadget.h b/include/linux/usb/gadget.h index ce2188d338e6..92467eea76de 100644 --- a/include/linux/usb/gadget.h +++ b/include/linux/usb/gadget.h @@ -1014,6 +1014,7 @@ static inline int usb_gadget_activate(struct usb_gadget *gadget) * @driver: Driver model state for this driver. * @udc_name: A name of UDC this driver should be bound to. If udc_name is NULL, * this driver will be bound to any available UDC. + * @pending: UDC core private data used for deferred probe of this driver. * * Devices are disabled till a gadget driver successfully bind()s, which * means the driver will handle setup() requests needed to enumerate (and @@ -1076,6 +1077,7 @@ struct usb_gadget_driver { struct device_driver driver; char *udc_name; + struct list_head pending; }; |