usb: gadget: composite: add usb_remove_function()

This will be used to remove a single function from a given config. Right
now "ignore" that an error at ->bind() time and cleanup later during
composite_unbind() / remove_config().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 4aa0e4652228..366facccf4f6 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -215,6 +215,18 @@ done:
 }
 EXPORT_SYMBOL_GPL(usb_add_function);
 
+void usb_remove_function(struct usb_configuration *c, struct usb_function *f)
+{
+        if (f->disable)
+                f->disable(f);
+
+        bitmap_zero(f->endpoints, 32);
+        list_del(&f->list);
+        if (f->unbind)
+                f->unbind(c, f);
+}
+EXPORT_SYMBOL_GPL(usb_remove_function);
+
 /**
  * usb_function_deactivate - prevent function and gadget enumeration
  * @function: the function that isn't yet ready to respond