usb: gadget: always update HS/SS descriptors and create a copy of them

HS and SS descriptors are staticaly created. They are updated during the
bind process with the endpoint address, string id or interface numbers.

After that, the descriptor chain is linked to struct usb_function which
is used by composite in order to serve the GET_DESCRIPTOR requests,
number of available configs and so on.

There is no need to assign the HS descriptor only if the UDC supports
HS speed because composite won't report those to the host if HS support
has not been reached. The same reasoning is valid for SS.

This patch makes sure each function updates HS/SS descriptors
unconditionally and uses the newly introduced helper function to create a
copy the descriptors for the speed which is supported by the UDC.

While at that, also rename f->descriptors to f->fs_descriptors in order
to make it more explicit what that means.

Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 9 insertions, 3 deletions

diff --git a/drivers/usb/gadget/printer.c b/drivers/usb/gadget/printer.c
index e156e3f2672..35bcc83d1e0 100644
--- a/drivers/usb/gadget/printer.c
+++ b/drivers/usb/gadget/printer.c
@@ -983,8 +983,10 @@ static int __init printer_func_bind(struct usb_configuration *c,
 {
 	struct printer_dev *dev = container_of(f, struct printer_dev, function);
 	struct usb_composite_dev *cdev = c->cdev;
-	struct usb_ep		*in_ep, *out_ep;
+	struct usb_ep *in_ep;
+	struct usb_ep *out_ep = NULL;
 	int id;
+	int ret;
 
 	id = usb_interface_id(c, f);
 	if (id < 0)
@@ -1010,6 +1012,11 @@ autoconf_fail:
 	hs_ep_in_desc.bEndpointAddress = fs_ep_in_desc.bEndpointAddress;
 	hs_ep_out_desc.bEndpointAddress = fs_ep_out_desc.bEndpointAddress;
 
+	ret = usb_assign_descriptors(f, fs_printer_function,
+			hs_printer_function, NULL);
+	if (ret)
+		return ret;
+
 	dev->in_ep = in_ep;
 	dev->out_ep = out_ep;
 	return 0;
@@ -1018,6 +1025,7 @@ autoconf_fail:
 static void printer_func_unbind(struct usb_configuration *c,
 		struct usb_function *f)
 {
+	usb_free_all_descriptors(f);
 }
 
 static int printer_func_set_alt(struct usb_function *f,
@@ -1110,8 +1118,6 @@ static int __init printer_bind_config(struct usb_configuration *c)
 	dev = &usb_printer_gadget;
 
 	dev->function.name = shortname;
-	dev->function.descriptors = fs_printer_function;
-	dev->function.hs_descriptors = hs_printer_function;
 	dev->function.bind = printer_func_bind;
 	dev->function.setup = printer_func_setup;
 	dev->function.unbind = printer_func_unbind;