usb: gadget: factor out alloc_ep_req

alloc_ep_req() is a function repeated in several modules.
Make a common implementation and use it.

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>

drivers/usb/gadget/Makefile

@@ -7,7 +7,7 @@ ccflags-$(CONFIG_USB_GADGET_VERBOSE)	+= -DVERBOSE_DEBUG
 obj-$(CONFIG_USB_GADGET)	+= udc-core.o
 obj-$(CONFIG_USB_LIBCOMPOSITE)	+= libcomposite.o
 libcomposite-y			:= usbstring.o config.o epautoconf.o
-libcomposite-y			+= composite.o functions.o configfs.o
+libcomposite-y			+= composite.o functions.o configfs.o u_f.o
 obj-$(CONFIG_USB_DUMMY_HCD)	+= dummy_hcd.o
 obj-$(CONFIG_USB_NET2272)	+= net2272.o
 obj-$(CONFIG_USB_NET2280)	+= net2280.o

drivers/usb/gadget/f_hid.c

@@ -20,6 +20,8 @@
 #include <linux/sched.h>
 #include <linux/usb/g_hid.h>
 
+#include "u_f.h"
+
 static int major, minors;
 static struct class *hidg_class;
 
@@ -334,20 +336,10 @@ static int f_hidg_open(struct inode *inode, struct file *fd)
 /*-------------------------------------------------------------------------*/
 /*                                usb_function                             */
 
-static struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep, unsigned length)
+static inline struct usb_request *hidg_alloc_ep_req(struct usb_ep *ep,
+						    unsigned length)
 {
-	struct usb_request *req;
-
-	req = usb_ep_alloc_request(ep, GFP_ATOMIC);
-	if (req) {
-		req->length = length;
-		req->buf = kmalloc(length, GFP_ATOMIC);
-		if (!req->buf) {
-			usb_ep_free_request(ep, req);
-			req = NULL;
-		}
-	}
-	return req;
+	return alloc_ep_req(ep, length, length);
 }
 
 static void hidg_set_report_complete(struct usb_ep *ep, struct usb_request *req)

drivers/usb/gadget/f_loopback.c

@@ -20,6 +20,7 @@
 #include <linux/usb/composite.h>
 
 #include "g_zero.h"
+#include "u_f.h"
 
 /*
  * LOOPBACK FUNCTION ... a testing vehicle for USB peripherals,
@@ -293,6 +294,11 @@ static void disable_loopback(struct f_loopback *loop)
 	VDBG(cdev, "%s disabled\n", loop->function.name);
 }
 
+static inline struct usb_request *lb_alloc_ep_req(struct usb_ep *ep, int len)
+{
+	return alloc_ep_req(ep, len, buflen);
+}
+
 static int
 enable_loopback(struct usb_composite_dev *cdev, struct f_loopback *loop)
 {
@@ -332,7 +338,7 @@ fail0:
 	 * than 'buflen' bytes each.
 	 */
 	for (i = 0; i < qlen && result == 0; i++) {
-		req = alloc_ep_req(ep, 0);
+		req = lb_alloc_ep_req(ep, 0);
 		if (req) {
 			req->complete = loopback_complete;
 			result = usb_ep_queue(ep, req, GFP_ATOMIC);

drivers/usb/gadget/f_midi.c

@@ -32,6 +32,8 @@
 #include <linux/usb/audio.h>
 #include <linux/usb/midi.h>
 
+#include "u_f.h"
+
 MODULE_AUTHOR("Ben Williamson");
 MODULE_LICENSE("GPL v2");
 
@@ -191,20 +193,10 @@ static struct usb_gadget_strings *midi_strings[] = {
 	NULL,
 };
 
-static struct usb_request *alloc_ep_req(struct usb_ep *ep, unsigned length)
+static inline struct usb_request *midi_alloc_ep_req(struct usb_ep *ep,
+						    unsigned length)
 {
-	struct usb_request *req;
-
-	req = usb_ep_alloc_request(ep, GFP_ATOMIC);
-	if (req) {
-		req->length = length;
-		req->buf = kmalloc(length, GFP_ATOMIC);
-		if (!req->buf) {
-			usb_ep_free_request(ep, req);
-			req = NULL;
-		}
-	}
-	return req;
+	return alloc_ep_req(ep, length, length);
 }
 
 static void free_ep_req(struct usb_ep *ep, struct usb_request *req)
@@ -365,7 +357,7 @@ static int f_midi_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
 	/* allocate a bunch of read buffers and queue them all at once. */
 	for (i = 0; i < midi->qlen && err == 0; i++) {
 		struct usb_request *req =
-			alloc_ep_req(midi->out_ep, midi->buflen);
+			midi_alloc_ep_req(midi->out_ep, midi->buflen);
 		if (req == NULL)
 			return -ENOMEM;
 
@@ -546,7 +538,7 @@ static void f_midi_transmit(struct f_midi *midi, struct usb_request *req)
 		return;
 
 	if (!req)
-		req = alloc_ep_req(ep, midi->buflen);
+		req = midi_alloc_ep_req(ep, midi->buflen);
 
 	if (!req) {
 		ERROR(midi, "gmidi_transmit: alloc_ep_request failed\n");

drivers/usb/gadget/f_sourcesink.c

@@ -21,6 +21,7 @@
 
 #include "g_zero.h"
 #include "gadget_chips.h"
+#include "u_f.h"
 
 /*
  * SOURCE/SINK FUNCTION ... a primary testing vehicle for USB peripheral
@@ -301,23 +302,9 @@ static struct usb_gadget_strings *sourcesink_strings[] = {
 
 /*-------------------------------------------------------------------------*/
 
-struct usb_request *alloc_ep_req(struct usb_ep *ep, int len)
+static inline struct usb_request *ss_alloc_ep_req(struct usb_ep *ep, int len)
 {
-	struct usb_request      *req;
-
-	req = usb_ep_alloc_request(ep, GFP_ATOMIC);
-	if (req) {
-		if (len)
-			req->length = len;
-		else
-			req->length = buflen;
-		req->buf = kmalloc(req->length, GFP_ATOMIC);
-		if (!req->buf) {
-			usb_ep_free_request(ep, req);
-			req = NULL;
-		}
-	}
-	return req;
+	return alloc_ep_req(ep, len, buflen);
 }
 
 void free_ep_req(struct usb_ep *ep, struct usb_request *req)
@@ -628,10 +615,10 @@ static int source_sink_start_ep(struct f_sourcesink *ss, bool is_in,
 				break;
 			}
 			ep = is_in ? ss->iso_in_ep : ss->iso_out_ep;
-			req = alloc_ep_req(ep, size);
+			req = ss_alloc_ep_req(ep, size);
 		} else {
 			ep = is_in ? ss->in_ep : ss->out_ep;
-			req = alloc_ep_req(ep, 0);
+			req = ss_alloc_ep_req(ep, 0);
 		}
 
 		if (!req)

drivers/usb/gadget/g_zero.h

@@ -36,7 +36,6 @@ void lb_modexit(void);
 int lb_modinit(void);
 
 /* common utilities */
-struct usb_request *alloc_ep_req(struct usb_ep *ep, int len);
 void free_ep_req(struct usb_ep *ep, struct usb_request *req);
 void disable_endpoints(struct usb_composite_dev *cdev,
 		struct usb_ep *in, struct usb_ep *out,

drivers/usb/gadget/u_f.c

@@ -0,0 +1,32 @@
+/*
+ * u_f.c -- USB function utilities for Gadget stack
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/usb/gadget.h>
+#include "u_f.h"
+
+struct usb_request *alloc_ep_req(struct usb_ep *ep, int len, int default_len)
+{
+	struct usb_request      *req;
+
+	req = usb_ep_alloc_request(ep, GFP_ATOMIC);
+	if (req) {
+		req->length = len ?: default_len;
+		req->buf = kmalloc(req->length, GFP_ATOMIC);
+		if (!req->buf) {
+			usb_ep_free_request(ep, req);
+			req = NULL;
+		}
+	}
+	return req;
+}
+EXPORT_SYMBOL(alloc_ep_req);

drivers/usb/gadget/u_f.h

@@ -0,0 +1,26 @@
+/*
+ * u_f.h
+ *
+ * Utility definitions for USB functions
+ *
+ * Copyright (c) 2013 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * Author: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __U_F_H__
+#define __U_F_H__
+
+struct usb_ep;
+struct usb_request;
+
+struct usb_request *alloc_ep_req(struct usb_ep *ep, int len, int default_len);
+
+#endif /* __U_F_H__ */
+
+