usb: gadget: f_fs: preserve wMaxPacketSize across usb_ep_autoconfig() call

usb_ep_autoconfig() treats the passed descriptor as if it were an fs
descriptor. In particular, for bulk endpoints, it clips wMaxPacketSize
to 64. This patch preserves the original value.

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 1e54304..66a2c16 100644 (file)
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -2843,12 +2843,18 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
                struct usb_request *req;
                struct usb_ep *ep;
                u8 bEndpointAddress;
+               u16 wMaxPacketSize;
 
                /*
                 * We back up bEndpointAddress because autoconfig overwrites
                 * it with physical endpoint address.
                 */
                bEndpointAddress = ds->bEndpointAddress;
+               /*
+                * We back up wMaxPacketSize because autoconfig treats
+                * endpoint descriptors as if they were full speed.
+                */
+               wMaxPacketSize = ds->wMaxPacketSize;
                pr_vdebug("autoconfig\n");
                ep = usb_ep_autoconfig(func->gadget, ds);
                if (unlikely(!ep))
@@ -2869,6 +2875,11 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
                 */
                if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
                        ds->bEndpointAddress = bEndpointAddress;
+               /*
+                * Restore wMaxPacketSize which was potentially
+                * overwritten by autoconfig.
+                */
+               ds->wMaxPacketSize = wMaxPacketSize;
        }
        ffs_dump_mem(": Rewritten ep desc", ds, ds->bLength);