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>

drivers/usb/gadget/composite.c

@@ -107,7 +107,7 @@ int config_ep_by_speed(struct usb_gadget *g,
 		}
 		/* else: fall through */
 	default:
-		speed_desc = f->descriptors;
+		speed_desc = f->fs_descriptors;
 	}
 	/* find descriptors */
 	for_each_ep_desc(speed_desc, d_spd) {
@@ -200,7 +200,7 @@ int usb_add_function(struct usb_configuration *config,
 	 * as full speed ... it's the function drivers that will need
 	 * to avoid bulk and ISO transfers.
 	 */
-	if (!config->fullspeed && function->descriptors)
+	if (!config->fullspeed && function->fs_descriptors)
 		config->fullspeed = true;
 	if (!config->highspeed && function->hs_descriptors)
 		config->highspeed = true;
@@ -363,7 +363,7 @@ static int config_buf(struct usb_configuration *config,
 			descriptors = f->hs_descriptors;
 			break;
 		default:
-			descriptors = f->descriptors;
+			descriptors = f->fs_descriptors;
 		}
 
 		if (!descriptors)
@@ -620,7 +620,7 @@ static int set_config(struct usb_composite_dev *cdev,
 			descriptors = f->hs_descriptors;
 			break;
 		default:
-			descriptors = f->descriptors;
+			descriptors = f->fs_descriptors;
 		}
 
 		for (; *descriptors; ++descriptors) {

drivers/usb/gadget/config.c

@@ -19,7 +19,7 @@
 
 #include <linux/usb/ch9.h>
 #include <linux/usb/gadget.h>
-
+#include <linux/usb/composite.h>
 
 /**
  * usb_descriptor_fillbuf - fill buffer with descriptors
@@ -158,3 +158,40 @@ usb_copy_descriptors(struct usb_descriptor_header **src)
 	return ret;
 }
 EXPORT_SYMBOL_GPL(usb_copy_descriptors);
+
+int usb_assign_descriptors(struct usb_function *f,
+		struct usb_descriptor_header **fs,
+		struct usb_descriptor_header **hs,
+		struct usb_descriptor_header **ss)
+{
+	struct usb_gadget *g = f->config->cdev->gadget;
+
+	if (fs) {
+		f->fs_descriptors = usb_copy_descriptors(fs);
+		if (!f->fs_descriptors)
+			goto err;
+	}
+	if (hs && gadget_is_dualspeed(g)) {
+		f->hs_descriptors = usb_copy_descriptors(hs);
+		if (!f->hs_descriptors)
+			goto err;
+	}
+	if (ss && gadget_is_superspeed(g)) {
+		f->ss_descriptors = usb_copy_descriptors(ss);
+		if (!f->ss_descriptors)
+			goto err;
+	}
+	return 0;
+err:
+	usb_free_all_descriptors(f);
+	return -ENOMEM;
+}
+EXPORT_SYMBOL_GPL(usb_assign_descriptors);
+
+void usb_free_all_descriptors(struct usb_function *f)
+{
+	usb_free_descriptors(f->fs_descriptors);
+	usb_free_descriptors(f->hs_descriptors);
+	usb_free_descriptors(f->ss_descriptors);
+}
+EXPORT_SYMBOL_GPL(usb_free_all_descriptors);

drivers/usb/gadget/f_acm.c

@@ -658,37 +658,22 @@ acm_bind(struct usb_configuration *c, struct usb_function *f)
 	acm->notify_req->complete = acm_cdc_notify_complete;
 	acm->notify_req->context = acm;
 
-	/* copy descriptors */
-	f->descriptors = usb_copy_descriptors(acm_fs_function);
-	if (!f->descriptors)
-		goto fail;
-
 	/* support all relevant hardware speeds... we expect that when
 	 * hardware is dual speed, all bulk-capable endpoints work at
 	 * both speeds
 	 */
-	if (gadget_is_dualspeed(c->cdev->gadget)) {
-		acm_hs_in_desc.bEndpointAddress =
-				acm_fs_in_desc.bEndpointAddress;
-		acm_hs_out_desc.bEndpointAddress =
-				acm_fs_out_desc.bEndpointAddress;
-		acm_hs_notify_desc.bEndpointAddress =
-				acm_fs_notify_desc.bEndpointAddress;
-
-		/* copy descriptors */
-		f->hs_descriptors = usb_copy_descriptors(acm_hs_function);
-	}
-	if (gadget_is_superspeed(c->cdev->gadget)) {
-		acm_ss_in_desc.bEndpointAddress =
-			acm_fs_in_desc.bEndpointAddress;
-		acm_ss_out_desc.bEndpointAddress =
-			acm_fs_out_desc.bEndpointAddress;
-
-		/* copy descriptors, and track endpoint copies */
-		f->ss_descriptors = usb_copy_descriptors(acm_ss_function);
-		if (!f->ss_descriptors)
-			goto fail;
-	}
+	acm_hs_in_desc.bEndpointAddress = acm_fs_in_desc.bEndpointAddress;
+	acm_hs_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress;
+	acm_hs_notify_desc.bEndpointAddress =
+		acm_fs_notify_desc.bEndpointAddress;
+
+	acm_ss_in_desc.bEndpointAddress = acm_fs_in_desc.bEndpointAddress;
+	acm_ss_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress;
+
+	status = usb_assign_descriptors(f, acm_fs_function, acm_hs_function,
+			acm_ss_function);
+	if (status)
+		goto fail;
 
 	DBG(cdev, "acm ttyGS%d: %s speed IN/%s OUT/%s NOTIFY/%s\n",
 			acm->port_num,
@@ -720,11 +705,7 @@ acm_unbind(struct usb_configuration *c, struct usb_function *f)
 {
 	struct f_acm		*acm = func_to_acm(f);
 
-	if (gadget_is_dualspeed(c->cdev->gadget))
-		usb_free_descriptors(f->hs_descriptors);
-	if (gadget_is_superspeed(c->cdev->gadget))
-		usb_free_descriptors(f->ss_descriptors);
-	usb_free_descriptors(f->descriptors);
+	usb_free_all_descriptors(f);
 	gs_free_req(acm->notify, acm->notify_req);
 	kfree(acm);
 }

drivers/usb/gadget/f_ecm.c

@@ -743,42 +743,24 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f)
 	ecm->notify_req->context = ecm;
 	ecm->notify_req->complete = ecm_notify_complete;
 
-	/* copy descriptors, and track endpoint copies */
-	f->descriptors = usb_copy_descriptors(ecm_fs_function);
-	if (!f->descriptors)
-		goto fail;
-
 	/* support all relevant hardware speeds... we expect that when
 	 * hardware is dual speed, all bulk-capable endpoints work at
 	 * both speeds
 	 */
-	if (gadget_is_dualspeed(c->cdev->gadget)) {
-		hs_ecm_in_desc.bEndpointAddress =
-				fs_ecm_in_desc.bEndpointAddress;
-		hs_ecm_out_desc.bEndpointAddress =
-				fs_ecm_out_desc.bEndpointAddress;
-		hs_ecm_notify_desc.bEndpointAddress =
-				fs_ecm_notify_desc.bEndpointAddress;
-
-		/* copy descriptors, and track endpoint copies */
-		f->hs_descriptors = usb_copy_descriptors(ecm_hs_function);
-		if (!f->hs_descriptors)
-			goto fail;
-	}
-
-	if (gadget_is_superspeed(c->cdev->gadget)) {
-		ss_ecm_in_desc.bEndpointAddress =
-				fs_ecm_in_desc.bEndpointAddress;
-		ss_ecm_out_desc.bEndpointAddress =
-				fs_ecm_out_desc.bEndpointAddress;
-		ss_ecm_notify_desc.bEndpointAddress =
-				fs_ecm_notify_desc.bEndpointAddress;
-
-		/* copy descriptors, and track endpoint copies */
-		f->ss_descriptors = usb_copy_descriptors(ecm_ss_function);
-		if (!f->ss_descriptors)
-			goto fail;
-	}
+	hs_ecm_in_desc.bEndpointAddress = fs_ecm_in_desc.bEndpointAddress;
+	hs_ecm_out_desc.bEndpointAddress = fs_ecm_out_desc.bEndpointAddress;
+	hs_ecm_notify_desc.bEndpointAddress =
+		fs_ecm_notify_desc.bEndpointAddress;
+
+	ss_ecm_in_desc.bEndpointAddress = fs_ecm_in_desc.bEndpointAddress;
+	ss_ecm_out_desc.bEndpointAddress = fs_ecm_out_desc.bEndpointAddress;
+	ss_ecm_notify_desc.bEndpointAddress =
+		fs_ecm_notify_desc.bEndpointAddress;
+
+	status = usb_assign_descriptors(f, ecm_fs_function, ecm_hs_function,
+			ecm_ss_function);
+	if (status)
+		goto fail;
 
 	/* NOTE:  all that is done without knowing or caring about
 	 * the network link ... which is unavailable to this code
@@ -796,11 +778,6 @@ ecm_bind(struct usb_configuration *c, struct usb_function *f)
 	return 0;
 
 fail:
-	if (f->descriptors)
-		usb_free_descriptors(f->descriptors);
-	if (f->hs_descriptors)
-		usb_free_descriptors(f->hs_descriptors);
-
 	if (ecm->notify_req) {
 		kfree(ecm->notify_req->buf);
 		usb_ep_free_request(ecm->notify, ecm->notify_req);
@@ -826,11 +803,7 @@ ecm_unbind(struct usb_configuration *c, struct usb_function *f)
 
 	DBG(c->cdev, "ecm unbind\n");
 
-	if (gadget_is_superspeed(c->cdev->gadget))
-		usb_free_descriptors(f->ss_descriptors);
-	if (gadget_is_dualspeed(c->cdev->gadget))
-		usb_free_descriptors(f->hs_descriptors);
-	usb_free_descriptors(f->descriptors);
+	usb_free_all_descriptors(f);
 
 	kfree(ecm->notify_req->buf);
 	usb_ep_free_request(ecm->notify, ecm->notify_req);

drivers/usb/gadget/f_eem.c

@@ -274,38 +274,20 @@ eem_bind(struct usb_configuration *c, struct usb_function *f)
 
 	status = -ENOMEM;
 
-	/* copy descriptors, and track endpoint copies */
-	f->descriptors = usb_copy_descriptors(eem_fs_function);
-	if (!f->descriptors)
-		goto fail;
-
 	/* support all relevant hardware speeds... we expect that when
 	 * hardware is dual speed, all bulk-capable endpoints work at
 	 * both speeds
 	 */
-	if (gadget_is_dualspeed(c->cdev->gadget)) {
-		eem_hs_in_desc.bEndpointAddress =
-				eem_fs_in_desc.bEndpointAddress;
-		eem_hs_out_desc.bEndpointAddress =
-				eem_fs_out_desc.bEndpointAddress;
-
-		/* copy descriptors, and track endpoint copies */
-		f->hs_descriptors = usb_copy_descriptors(eem_hs_function);
-		if (!f->hs_descriptors)
-			goto fail;
-	}
+	eem_hs_in_desc.bEndpointAddress = eem_fs_in_desc.bEndpointAddress;
+	eem_hs_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress;
 
-	if (gadget_is_superspeed(c->cdev->gadget)) {
-		eem_ss_in_desc.bEndpointAddress =
-				eem_fs_in_desc.bEndpointAddress;
-		eem_ss_out_desc.bEndpointAddress =
-				eem_fs_out_desc.bEndpointAddress;
+	eem_ss_in_desc.bEndpointAddress = eem_fs_in_desc.bEndpointAddress;
+	eem_ss_out_desc.bEndpointAddress = eem_fs_out_desc.bEndpointAddress;
 
-		/* copy descriptors, and track endpoint copies */
-		f->ss_descriptors = usb_copy_descriptors(eem_ss_function);
-		if (!f->ss_descriptors)
-			goto fail;
-	}
+	status = usb_assign_descriptors(f, eem_fs_function, eem_hs_function,
+			eem_ss_function);
+	if (status)
+		goto fail;
 
 	DBG(cdev, "CDC Ethernet (EEM): %s speed IN/%s OUT/%s\n",
 			gadget_is_superspeed(c->cdev->gadget) ? "super" :
@@ -314,11 +296,7 @@ eem_bind(struct usb_configuration *c, struct usb_function *f)
 	return 0;
 
 fail:
-	if (f->descriptors)
-		usb_free_descriptors(f->descriptors);
-	if (f->hs_descriptors)
-		usb_free_descriptors(f->hs_descriptors);
-
+	usb_free_all_descriptors(f);
 	if (eem->port.out_ep)
 		eem->port.out_ep->driver_data = NULL;
 	if (eem->port.in_ep)
@@ -336,11 +314,7 @@ eem_unbind(struct usb_configuration *c, struct usb_function *f)
 
 	DBG(c->cdev, "eem unbind\n");
 
-	if (gadget_is_superspeed(c->cdev->gadget))
-		usb_free_descriptors(f->ss_descriptors);
-	if (gadget_is_dualspeed(c->cdev->gadget))
-		usb_free_descriptors(f->hs_descriptors);
-	usb_free_descriptors(f->descriptors);
+	usb_free_all_descriptors(f);
 	kfree(eem);
 }
 

drivers/usb/gadget/f_fs.c

@@ -2097,7 +2097,7 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
 	if (isHS)
 		func->function.hs_descriptors[(long)valuep] = desc;
 	else
-		func->function.descriptors[(long)valuep]    = desc;
+		func->function.fs_descriptors[(long)valuep]    = desc;
 
 	if (!desc || desc->bDescriptorType != USB_DT_ENDPOINT)
 		return 0;
@@ -2249,7 +2249,7 @@ static int ffs_func_bind(struct usb_configuration *c,
 	 * numbers without worrying that it may be described later on.
 	 */
 	if (likely(full)) {
-		func->function.descriptors = data->fs_descs;
+		func->function.fs_descriptors = data->fs_descs;
 		ret = ffs_do_descs(ffs->fs_descs_count,
 				   data->raw_descs,
 				   sizeof data->raw_descs,

drivers/usb/gadget/f_hid.c

@@ -573,7 +573,6 @@ static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
 		goto fail;
 	hidg_interface_desc.bInterfaceNumber = status;
 
-
 	/* allocate instance-specific endpoints */
 	status = -ENODEV;
 	ep = usb_ep_autoconfig(c->cdev->gadget, &hidg_fs_in_ep_desc);
@@ -609,20 +608,15 @@ static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
 	hidg_desc.desc[0].wDescriptorLength =
 		cpu_to_le16(hidg->report_desc_length);
 
-	/* copy descriptors */
-	f->descriptors = usb_copy_descriptors(hidg_fs_descriptors);
-	if (!f->descriptors)
-		goto fail;
+	hidg_hs_in_ep_desc.bEndpointAddress =
+		hidg_fs_in_ep_desc.bEndpointAddress;
+	hidg_hs_out_ep_desc.bEndpointAddress =
+		hidg_fs_out_ep_desc.bEndpointAddress;
 
-	if (gadget_is_dualspeed(c->cdev->gadget)) {
-		hidg_hs_in_ep_desc.bEndpointAddress =
-			hidg_fs_in_ep_desc.bEndpointAddress;
-		hidg_hs_out_ep_desc.bEndpointAddress =
-			hidg_fs_out_ep_desc.bEndpointAddress;
-		f->hs_descriptors = usb_copy_descriptors(hidg_hs_descriptors);
-		if (!f->hs_descriptors)
-			goto fail;
-	}
+	status = usb_assign_descriptors(f, hidg_fs_descriptors,
+			hidg_hs_descriptors, NULL);
+	if (status)
+		goto fail;
 
 	mutex_init(&hidg->lock);
 	spin_lock_init(&hidg->spinlock);
@@ -649,9 +643,7 @@ static int __init hidg_bind(struct usb_configuration *c, struct usb_function *f)
 			usb_ep_free_request(hidg->in_ep, hidg->req);
 	}
 
-	usb_free_descriptors(f->hs_descriptors);
-	usb_free_descriptors(f->descriptors);
-
+	usb_free_all_descriptors(f);
 	return status;
 }
 
@@ -668,9 +660,7 @@ static void hidg_unbind(struct usb_configuration *c, struct usb_function *f)
 	kfree(hidg->req->buf);
 	usb_ep_free_request(hidg->in_ep, hidg->req);
 
-	/* free descriptors copies */
-	usb_free_descriptors(f->hs_descriptors);
-	usb_free_descriptors(f->descriptors);
+	usb_free_all_descriptors(f);
 
 	kfree(hidg->report_desc);
 	kfree(hidg);