Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1752926AbdHIPLD (ORCPT <rfc822;w@1wt.eu>);
        Wed, 9 Aug 2017 11:11:03 -0400
Received: from mail-pg0-f67.google.com ([74.125.83.67]:37185 "EHLO
        mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
        with ESMTP id S1752047AbdHIPLB (ORCPT
        <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 9 Aug 2017 11:11:01 -0400
Content-Type: text/plain;
        charset=us-ascii
Mime-Version: 1.0 (1.0)
Subject: Re: f_hid.c conversion to the new function interface and crash due to race
From: Variksla <variksla@gmail.com>
X-Mailer: iPhone Mail (14G60)
In-Reply-To: <87a8399i9b.fsf@linux.intel.com>
Date: Wed, 9 Aug 2017 08:10:59 -0700
Cc: bjorn@mork.no, gregkh@linuxfoundation.org,
        linux-kernel@vger.kernel.org, jikos@kernel.org,
        linux-usb@vger.kernel.org, Pavel Machek <pavel@ucw.cz>, balbi@ti.com,
        eu@felipetonello.com, k.opasiak@samsung.com
Message-Id: <F9CD614C-2D81-4024-99EA-B3BD6F640916@gmail.com>
References: <CAES_P+_c3-_Z5=gw1k2zO-dtRXRhZU2GkQe+2YpwbQfbC7VHjQ@mail.gmail.com> <87a8399i9b.fsf@linux.intel.com>
To: Felipe Balbi <felipe.balbi@linux.intel.com>
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org
Content-Transfer-Encoding: 8bit
X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id v79FB8BP030101
Content-Length: 1173
Lines: 37



> On Aug 9, 2017, at 2:56 AM, Felipe Balbi <felipe.balbi@linux.intel.com> wrote:

Thanks for replying.
> 
> 
> Hi,
> 
> noman pouigt <variksla@gmail.com> writes:
>> Hello,
>> 
>> I am currently using 3.18 linux kernel and getting below
> 
> return -EKERNELTOOOLD;
> 
> Sorry, you're on your own. You should ask for support from whoever
> forces you to use 3.18 kernel.

I have updated f_hid.c file to latest kernel though as I knew it would be too much to ask to get support for old code.

I am just not sure about how to instantiate the function driver as earlier f_fs was instantiating the hid driver. However, after hid got converted to new function driver who is responsible for calling setup, bind and unbind functions in f_hid.c ?

Below is the glue code in android.c.
drivers/usb/gadget/android.c
static struct android_usb_function hid_function = {
       .name           = "hid",
       .init           = hid_function_init,
       .cleanup        = hid_function_cleanup,
       .bind_config    = hid_function_bind_config,
       .attributes     = hid_function_attributes,
};

Is there something similar in new function driver in upstream kernel?
> 
> -- 
> balbi