From patchwork Wed May 21 21:39:26 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tilman Schmidt X-Patchwork-Id: 351331 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id C7A4B140083 for ; Thu, 22 May 2014 07:42:37 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753795AbaEUVma (ORCPT ); Wed, 21 May 2014 17:42:30 -0400 Received: from mail.pxnet.com ([89.1.7.7]:43123 "EHLO mail.pxnet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753787AbaEUVm2 (ORCPT ); Wed, 21 May 2014 17:42:28 -0400 Received: from xenon.ts.pxnet.com (p57A57697.dip0.t-ipconnect.de [87.165.118.151]) (user=ts author=<> mech=DIGEST-MD5 bits=0) by mail.pxnet.com (8.13.8/8.13.8) with ESMTP id s4LLdcjT027265 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Wed, 21 May 2014 23:39:58 +0200 Received: by xenon.ts.pxnet.com (Postfix, from userid 1000) id DBBF0140075; Wed, 21 May 2014 23:39:26 +0200 (CEST) To: netdev@vger.kernel.org CC: Paul Bolle , isdn4linux@listserv.isdn4linux.de, "Keil, Karsten" , Jiri Slaby , Greg Kroah-Hartman Message-Id: <64bcfeb7b92c7e34c7b2837f9a646fcef81d1324.1400449372.git.tilman@imap.cc> In-Reply-To: References: From: Tilman Schmidt Subject: [PATCH 4/4] isdn/capi: fix (middleware) device nodes Date: Wed, 21 May 2014 23:39:26 +0200 (CEST) X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.2.7 (mail.pxnet.com [89.1.7.7]); Wed, 21 May 2014 23:40:18 +0200 (CEST) X-Scanned-By: MIMEDefang 2.70 on 89.1.7.7 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Paul Bolle Since v2.4 the capi driver used the following device nodes if "middleware" support was enabled: /dev/capi20 /dev/capi/0 /dev/capi/1 [...] /dev/capi20 is a character device node. /dev/capi/0 (and up) are tty device nodes (with a different major). This device node (naming) scheme is not documented anywhere, as far as I know. It was originally provided by the capifs pseudo filesystem (before udev became available). It is required for example by the pppd capiplugin. It was supported until a few years ago. But a number of developments broke it: - v2.6.6 (May 2004) renamed /dev/capi20 to /dev/capi and removed the "/" from the name of capi's tty driver. The explanation of the patch that did this included two examples of udev rules "to restore the old namespace"; - either udev 154 (May 2010) or udev 179 (January 2012) stopped allowing to rename device nodes, and thus the ability to have /dev/capi20 appear instead of /dev/capi and /dev/capi/0 (and up) instead of /dev/capi0 (and up); - v3.0 (July 2011) also removed capifs. That disabled another method to create the /dev/capi/0 (and up) device nodes. So now users need to manually tweak their setup (eg, create /dev/capi/ and fill that with symlinks) to get things working. This is all rather hacky and only discoverable by searching the web. Fix all this by renaming /dev/capi back to /dev/capi20, and by adding a devnode() callback to the "capi_nc" tty driver so the tty device nodes appear as /dev/capi/0 (and up). Signed-off-by: Paul Bolle Signed-off-by: Tilman Schmidt --- drivers/isdn/capi/Kconfig | 2 +- drivers/isdn/capi/capi.c | 8 +++++++- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/drivers/isdn/capi/Kconfig b/drivers/isdn/capi/Kconfig index 1d7adff..7641b30 100644 --- a/drivers/isdn/capi/Kconfig +++ b/drivers/isdn/capi/Kconfig @@ -9,7 +9,7 @@ config CAPI_TRACE If unsure, say Y. config ISDN_CAPI_CAPI20 - tristate "CAPI2.0 /dev/capi support" + tristate "CAPI2.0 /dev/capi20 support" help This option will provide the CAPI 2.0 interface to userspace applications via /dev/capi20. Applications should use the diff --git a/drivers/isdn/capi/capi.c b/drivers/isdn/capi/capi.c index ac6f72b..e9afa74 100644 --- a/drivers/isdn/capi/capi.c +++ b/drivers/isdn/capi/capi.c @@ -1250,6 +1250,11 @@ static const struct tty_operations capinc_ops = { .cleanup = capinc_tty_cleanup, }; +static char *capi_devnode(struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "capi/%u", MINOR(dev->devt)); +} + static int __init capinc_tty_init(void) { struct tty_driver *drv; @@ -1272,6 +1277,7 @@ static int __init capinc_tty_init(void) } drv->driver_name = "capi_nc"; drv->name = "capi"; + drv->devnode = capi_devnode; drv->major = 0; drv->minor_start = 0; drv->type = TTY_DRIVER_TYPE_SERIAL; @@ -1417,7 +1423,7 @@ static int __init capi_init(void) return PTR_ERR(capi_class); } - device_create(capi_class, NULL, MKDEV(capi_major, 0), NULL, "capi"); + device_create(capi_class, NULL, MKDEV(capi_major, 0), NULL, "capi20"); if (capinc_tty_init() < 0) { device_destroy(capi_class, MKDEV(capi_major, 0));