Users can apply i/o in the wrong direction on an endpoint to stall it. In case there is an error that does not allow the endpoint to be stalled, we want the user to know. An operation to stall the endpoint will return EBADMSG if successful, EAGAIN if there are still queued requests, and other errors depending on the underlying implementation. Also remove the conditional since it is always true. Signed-off-by: Jerry Zhang <zhangjerry@xxxxxxxxxx> --- Notes for v1: - What's the reasoning behind having this behavior in epfile_io? We could also consider moving this codepath to an ioctl and documenting it. drivers/usb/gadget/function/f_fs.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index d21874b35cf6..9990944a7245 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -961,10 +961,9 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data) /* In the meantime, endpoint got disabled or changed. */ ret = -ESHUTDOWN; } else if (halt) { - /* Halt */ - if (likely(epfile->ep == ep) && !WARN_ON(!ep->ep)) - usb_ep_set_halt(ep->ep); - ret = -EBADMSG; + ret = usb_ep_set_halt(ep->ep); + if (!ret) + ret = -EBADMSG; } else if (unlikely(data_len == -EINVAL)) { /* * Sanity Check: even though data_len can't be used -- 2.14.0.434.g98096fd7a8-goog -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html