Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755410AbbDTP50 (ORCPT ); Mon, 20 Apr 2015 11:57:26 -0400 Received: from quartz.orcorp.ca ([184.70.90.242]:57267 "EHLO quartz.orcorp.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752173AbbDTP5V (ORCPT ); Mon, 20 Apr 2015 11:57:21 -0400 Date: Mon, 20 Apr 2015 09:56:48 -0600 From: Jason Gunthorpe To: Greg Kroah-Hartman Cc: Russell King - ARM Linux , Jens Wiklander , valentin.manea@huawei.com, devicetree@vger.kernel.org, javier@javigon.com, emmanuel.michel@st.com, Herbert Xu , Arnd Bergmann , linux-kernel@vger.kernel.org, jean-michel.delorme@st.com, tpmdd-devel@lists.sourceforge.net, linux-arm-kernel@lists.infradead.org Subject: Re: [tpmdd-devel] [RFC PATCH 1/2] tee: generic TEE subsystem Message-ID: <20150420155648.GA7676@obsidianresearch.com> References: <1429257057-7935-1-git-send-email-jens.wiklander@linaro.org> <1429257057-7935-2-git-send-email-jens.wiklander@linaro.org> <20150417163054.GA28241@obsidianresearch.com> <20150418090147.GF12732@n2100.arm.linux.org.uk> <20150418172923.GA10605@obsidianresearch.com> <20150418215755.GM12732@n2100.arm.linux.org.uk> <20150420050800.GA12928@obsidianresearch.com> <20150420145432.GD7261@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150420145432.GD7261@kroah.com> User-Agent: Mutt/1.5.21 (2010-09-15) X-Broken-Reverse-DNS: no host name found for IP address 10.0.0.183 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 931 Lines: 23 On Mon, Apr 20, 2015 at 04:54:32PM +0200, Greg Kroah-Hartman wrote: > On Sun, Apr 19, 2015 at 11:08:00PM -0600, Jason Gunthorpe wrote: > > I still suspect the expected way to write a new mid layer is to create > > your own struct device and not rely on misc_device, > > Yes, that is the way. You can not use misc_device for anything other > than creating the char node that your driver can use through the fileops > you pass to it. > > Do not use a misc_device to create sysfs files for, or anything else, it > will be wrong and racy, as you have pointed out. Thanks! Can you quickly comment on when a misc device should be used compared to alloc_chrdev_region & cdev_add ? Jason -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/