From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751590AbcJJTYf (ORCPT ); Mon, 10 Oct 2016 15:24:35 -0400 Received: from mout.kundenserver.de ([212.227.126.131]:52457 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751100AbcJJTYe (ORCPT ); Mon, 10 Oct 2016 15:24:34 -0400 From: Arnd Bergmann To: Greg Kroah-Hartman Cc: Lubomir Rintel , linux-kernel@vger.kernel.org, Dominik Brodowski Subject: Re: [PATCH] char/pcmcia: add scr24x_cs chip card interface driver Date: Mon, 10 Oct 2016 21:24:10 +0200 Message-ID: <2290612.ZfX1KippBh@wuerfel> User-Agent: KMail/5.1.3 (Linux/4.4.0-34-generic; KDE/5.18.0; x86_64; ; ) In-Reply-To: <20161010173345.GA8476@kroah.com> References: <1476115095-8497-1-git-send-email-lkundrak@v3.sk> <20161010173345.GA8476@kroah.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Provags-ID: V03:K0:D5DQbhZbGJHSQx1SBvS0ogza1sb4eouRLApioZnJfTzH7GXO9hB E/z2cMRC1xtjxMSH2I9KneKMBmqEeHko7KiQe2cyl/zuXrSWtJ1oAJYTRfIuhPTtxT2YFBM MVnc7PUwoswYMG4QABhEvVPXdlZ2Tnih+wMC0XJtOhA19F82jAuoOY8kYjRpMRWHI/GjK1D tkPI5IYxgXEWczbPE4vVA== X-UI-Out-Filterresults: notjunk:1;V01:K0:0uShMJzJcUw=:Ii8SVqZDhtcaUm69GtQGh8 jk0yKfUjLmNpu36WMl7GBiO5tYGqhjlv8f5i/m+o4+Wf0Z6lqd7KQGW1RyRSZd1r5POsUgaww ZFz1clDFO/njQhnJqVhV+wRYR9QM7hIS9cf2w1IuppQeC6jwH7F82thw1VLTH6bgZgEvTE8kN wb/fISrW00ukt77ZFgVlGbMt0udiYfyAqlnENQUY6jZ+ri/jQLUwUXEx2/xgJ6WXo/FVlh8HA neDjZ/auZ9gmoFT5B4apZyvaAX6sFzRjrSSrx95i/tAyShvcZ2WlkT1CCJcrvtBTqtOQkXUw2 Yi2TCcUpgopaPU+n29yP1BReDJL8EQlzBRhDXgJhD2eq4SlovTGVESI1uIyn/ILjxhYcrCTLl WGy1OX1R0F9oSaU4NjOEwi27se5fqhKSkzp63msTE1YfUzpSuQm56A3esiILkpLJMLWr2tvwK ArDJ+bT30XF5UNklAHMwGumgzrjW2SPn496/NbolVJkuF3AKvROtwUqd1aPDT3krSW0yt+gjs r86bkNRzP/FiUGSNYoJEGoQmoOdFnYyGrcEl2MBDo/PPSIUM9JZPXLj6mpE0tqQ++wcP6H+9D 3umcWBn7NS5sxZ/p5L06y93CkWM2bmK2LaYgOwuJjzREcLi3ZcanthyXOUD32oP+0kISGxeKV /3HKou34RYRDH6Voy9nf+ViqGywBMDwwxj+ucrFjzfi/gHjRj4nbtCUEUb3TQcckegM9KNSph Y3Eo9DWJ1k04pwwk Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Monday, October 10, 2016 7:33:45 PM CEST Greg Kroah-Hartman wrote: > > + > > +#define SCR24X_DEVS 8 > > +static DECLARE_BITMAP(scr24x_minors, SCR24X_DEVS); > > + > > +static struct class *scr24x_class; > > +dev_t scr24x_devt; > > global variable? And why do you need a char device for this type of > hardware? Isn't there already an existing interface for this device > class? It looks like this is modeled after the other two chip card drivers in drivers/char/pcmcia/, which are also char devices. Looking at https://pcsclite.alioth.debian.org/ccid.html, it seems that other drivers for this protocol are typically in user space when they are for USB devices, so apparently no existing subsystem abstraction in the kernel. This reminds me that there is just one other driver in drivers/char/pcmcia (synclink_cs), and that should be moved to drivers/tty/ with the other synclink variants. If we do this, we could rename drivers/char/pcmcia to something that implies "smartcard". Arnd