From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Kroah-Hartman Subject: Re: [PATCH 3/3] isdn/capi: fix (middleware) device nodes Date: Sun, 1 Jun 2014 14:52:14 -0700 Message-ID: <20140601215214.GA16029@kroah.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, David Miller , Paul Bolle , Karsten Keil , isdn4linux@listserv.isdn4linux.de, Jiri Slaby To: Tilman Schmidt Return-path: Received: from mail.linuxfoundation.org ([140.211.169.12]:57396 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752363AbaFAVwS (ORCPT ); Sun, 1 Jun 2014 17:52:18 -0400 Content-Disposition: inline In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On Sun, Jun 01, 2014 at 11:47:24PM +0200, Tilman Schmidt wrote: > 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 setting the name of the > "capi_nc" tty driver to "capi!" 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 | 4 ++-- > 2 files changed, 3 insertions(+), 3 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..f9a87ed 100644 > --- a/drivers/isdn/capi/capi.c > +++ b/drivers/isdn/capi/capi.c > @@ -1271,7 +1271,7 @@ static int __init capinc_tty_init(void) > return -ENOMEM; > } > drv->driver_name = "capi_nc"; > - drv->name = "capi"; > + drv->name = "capi!"; > drv->major = 0; > drv->minor_start = 0; > drv->type = TTY_DRIVER_TYPE_SERIAL; > @@ -1417,7 +1417,7 @@ 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)); Much nicer than the previous patches to resolve this issue :) Acked-by: Greg Kroah-Hartman