usb: gadget: f_mass_storage: create fsg_common_set_cdev for use in fsg_common_init

fsg_common_init is a lengthy function. Factor a portion of it out.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/gadget/f_mass_storage.c b/drivers/usb/gadget/f_mass_storage.c
index cb789fa..e61c066 100644
--- a/drivers/usb/gadget/f_mass_storage.c
+++ b/drivers/usb/gadget/f_mass_storage.c
@@ -2810,6 +2810,33 @@
 	return 0;
 }
 
+int fsg_common_set_cdev(struct fsg_common *common,
+			 struct usb_composite_dev *cdev, bool can_stall)
+{
+	struct usb_string *us;
+
+	common->gadget = cdev->gadget;
+	common->ep0 = cdev->gadget->ep0;
+	common->ep0req = cdev->req;
+	common->cdev = cdev;
+
+	us = usb_gstrings_attach(cdev, fsg_strings_array,
+				 ARRAY_SIZE(fsg_strings));
+	if (IS_ERR(us))
+		return PTR_ERR(us);
+
+	fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
+
+	/*
+	 * Some peripheral controllers are known not to be able to
+	 * halt bulk endpoints correctly.  If one of them is present,
+	 * disable stalls.
+	 */
+	common->can_stall = can_stall && !(gadget_is_at91(common->gadget));
+
+	return 0;
+}
+
 struct fsg_common *fsg_common_init(struct fsg_common *common,
 				   struct usb_composite_dev *cdev,
 				   struct fsg_config *cfg)
@@ -2817,7 +2844,6 @@
 	struct usb_gadget *gadget = cdev->gadget;
 	struct fsg_lun **curlun_it;
 	struct fsg_lun_config *lcfg;
-	struct usb_string *us;
 	int nluns, i, rc;
 	char *pathbuf;
 
@@ -2837,19 +2863,9 @@
 	common->ops = cfg->ops;
 	common->private_data = cfg->private_data;
 
-	common->gadget = gadget;
-	common->ep0 = gadget->ep0;
-	common->ep0req = cdev->req;
-	common->cdev = cdev;
-
-	us = usb_gstrings_attach(cdev, fsg_strings_array,
-				 ARRAY_SIZE(fsg_strings));
-	if (IS_ERR(us)) {
-		rc = PTR_ERR(us);
+	rc = fsg_common_set_cdev(common, cdev, cfg->can_stall);
+	if (rc)
 		goto error_release;
-	}
-	fsg_intf_desc.iInterface = us[FSG_STRING_INTERFACE].id;
-
 
 	rc = fsg_common_set_nluns(common, cfg->nluns);
 	if (rc)
@@ -2925,14 +2941,6 @@
 				     : "File-Stor Gadget"),
 		 i);
 
-	/*
-	 * Some peripheral controllers are known not to be able to
-	 * halt bulk endpoints correctly.  If one of them is present,
-	 * disable stalls.
-	 */
-	common->can_stall = cfg->can_stall &&
-		!(gadget_is_at91(common->gadget));
-
 
 	/* Tell the thread to start working */
 	common->thread_task =
diff --git a/drivers/usb/gadget/f_mass_storage.h b/drivers/usb/gadget/f_mass_storage.h
index f98c792..de7aa32 100644
--- a/drivers/usb/gadget/f_mass_storage.h
+++ b/drivers/usb/gadget/f_mass_storage.h
@@ -106,6 +106,9 @@
 
 int fsg_common_set_num_buffers(struct fsg_common *common, unsigned int n);
 
+int fsg_common_set_cdev(struct fsg_common *common,
+			struct usb_composite_dev *cdev, bool can_stall);
+
 void fsg_common_remove_lun(struct fsg_lun *lun, bool sysfs);
 
 void fsg_common_remove_luns(struct fsg_common *common);