From cb678a3a725816b3d76d0e822c6e7e786e756f82 Mon Sep 17 00:00:00 2001 From: Benoit Goby Date: Wed, 25 May 2011 23:59:43 -0700 Subject: [PATCH] usb: gadget: composite: Add usb_remove_config This allows composite drivers to dynamically change their configuration. For example, a driver might remove a configuration and register a new one with a different set of functions. User should prevent the host from enumerating the device while changing the configuration: usb_gadget_disconnect(cdev->gadget); usb_remove_config(cdev, old_config); usb_add_config(cdev, new_config, new_conf_bind); usb_gadget_connect(cdev->gadget); Change-Id: Icbfb4ce41685fde9bf63d5d58fca1ad242aa69f9 Signed-off-by: Benoit Goby --- drivers/usb/gadget/composite.c | 60 ++++++++++++++++++++++++++++-------------- include/linux/usb/composite.h | 3 +++ 2 files changed, 43 insertions(+), 20 deletions(-) diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c index c9ae8bb..6c8fbb1 100644 --- a/drivers/usb/gadget/composite.c +++ b/drivers/usb/gadget/composite.c @@ -667,6 +667,45 @@ done: return status; } +static int remove_config(struct usb_composite_dev *cdev, + struct usb_configuration *config) +{ + while (!list_empty(&config->functions)) { + struct usb_function *f; + + f = list_first_entry(&config->functions, + struct usb_function, list); + list_del(&f->list); + if (f->unbind) { + DBG(cdev, "unbind function '%s'/%p\n", f->name, f); + f->unbind(config, f); + /* may free memory for "f" */ + } + } + list_del(&config->list); + if (config->unbind) { + DBG(cdev, "unbind config '%s'/%p\n", config->label, config); + config->unbind(config); + /* may free memory for "c" */ + } + return 0; +} + +int usb_remove_config(struct usb_composite_dev *cdev, + struct usb_configuration *config) +{ + unsigned long flags; + + spin_lock_irqsave(&cdev->lock, flags); + + if (cdev->config == config) + reset_config(cdev); + + spin_unlock_irqrestore(&cdev->lock, flags); + + return remove_config(cdev, config); +} + /*-------------------------------------------------------------------------*/ /* We support strings in multiple languages ... string descriptor zero @@ -1192,28 +1231,9 @@ composite_unbind(struct usb_gadget *gadget) while (!list_empty(&cdev->configs)) { struct usb_configuration *c; - c = list_first_entry(&cdev->configs, struct usb_configuration, list); - while (!list_empty(&c->functions)) { - struct usb_function *f; - - f = list_first_entry(&c->functions, - struct usb_function, list); - list_del(&f->list); - if (f->unbind) { - DBG(cdev, "unbind function '%s'/%p\n", - f->name, f); - f->unbind(c, f); - /* may free memory for "f" */ - } - } - list_del(&c->list); - if (c->unbind) { - DBG(cdev, "unbind config '%s'/%p\n", c->label, c); - c->unbind(c); - /* may free memory for "c" */ - } + remove_config(cdev, c); } if (composite->unbind) composite->unbind(cdev); diff --git a/include/linux/usb/composite.h b/include/linux/usb/composite.h index 106c69c..d00ab95 100644 --- a/include/linux/usb/composite.h +++ b/include/linux/usb/composite.h @@ -249,6 +249,9 @@ int usb_add_config(struct usb_composite_dev *, struct usb_configuration *, int (*)(struct usb_configuration *)); +int usb_remove_config(struct usb_composite_dev *, + struct usb_configuration *); + /** * struct usb_composite_driver - groups configurations into a gadget * @name: For diagnostics, identifies the driver. -- 2.7.4