usb: gadget: ffs: fix enable multiple instances

This patch fixes an "off-by-one" bug found in
581791f (FunctionFS: enable multiple functions).

During gfs_bind/gfs_unbind the functionfs_bind/functionfs_unbind should be
called for every functionfs instance. With the "i" pre-decremented they
were not called for the zeroth instance.

Acked-by: Michal Nazarewicz <mina86@mina86.com>
Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: <stable@vger.kernel.org>
[ balbi@ti.com : added offending commit's subject ]

Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/g_ffs.c b/drivers/usb/gadget/g_ffs.c
index 3953dd4..3b343b2 100644 (file)
--- a/drivers/usb/gadget/g_ffs.c
+++ b/drivers/usb/gadget/g_ffs.c
@@ -357,7 +357,7 @@ static int gfs_bind(struct usb_composite_dev *cdev)
                goto error;
        gfs_dev_desc.iProduct = gfs_strings[USB_GADGET_PRODUCT_IDX].id;
 
-       for (i = func_num; --i; ) {
+       for (i = func_num; i--; ) {
                ret = functionfs_bind(ffs_tab[i].ffs_data, cdev);
                if (unlikely(ret < 0)) {
                        while (++i < func_num)
@@ -413,7 +413,7 @@ static int gfs_unbind(struct usb_composite_dev *cdev)
                gether_cleanup();
        gfs_ether_setup = false;
 
-       for (i = func_num; --i; )
+       for (i = func_num; i--; )
                if (ffs_tab[i].ffs_data)
                        functionfs_unbind(ffs_tab[i].ffs_data);