Merge tag 'isdn-removal' of https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground

Arnd Bergmann says:

====================
isdn: deprecate non-mISDN drivers

When isdn4linux came up in the context of another patch series, I
remembered that we had discussed removing it a while ago.

It turns out that the suggestion from Karsten Keil wa to remove I4L
in 2018 after the last public ISDN networks are shut down. This has
happened now (with a very small number of exceptions), so I guess it's
time to try again.

We currently have three ISDN stacks in the kernel: the original
isdn4linux (with the hisax driver), the newer CAPI (with four drivers),
and finally the mISDN stack (supporting roughly the same hardware as
hisax).

As far as I can tell, anyone using ISDN with mainline kernel drivers in
the past few years uses mISDN, and this is typically used for voice-only
PBX installations that don't require a public network.

The older stacks support additional features for data networks, but those
typically make no sense any more if there is no network to connect to.

My proposal for this time is to kill off isdn4linux entirely, as it seems
to have been unusable for quite a while. This code has been abandoned
for many years and it does cause problems for treewide maintenance as
it tends to do everything that we try to stop doing.
Birger Harzenetter mentioned that is is still using i4l in order to
make use of the 'divert' feature that is not part of mISDN, but has
otherwise moved on to mISDN for normal operation, like apparently
everyone else.

CAPI in turn is not quite as obsolete, but two of the drivers (avm
and hysdn) don't seem to be used at all, while another one (gigaset)
will stop being maintained as Paul Bolle is no longer able to
test it after the network gets shut down in September.
All three are now moved into drivers/staging to let others speak
up in case there are remaining users.
This leaves Bluetooth CMTP as the only remaining user of CAPI, but
Marcel Holtmann wishes to keep maintaining it.

For the discussion on version 1, see [2]
Unfortunately, Karsten Keil as the maintainer has not participated in
the discussion.

      Arnd

[1] https://patchwork.kernel.org/patch/8484861/#17900371
[2] https://listserv.isdn4linux.de/pipermail/isdn4linux/2019-April/thread.html
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 0 insertions, 112 deletions

diff --git a/include/linux/concap.h b/include/linux/concap.h
deleted file mode 100644
index 977acb3d1fb2..000000000000
--- a/include/linux/concap.h
+++ /dev/null
@@ -1,112 +0,0 @@
-/* $Id: concap.h,v 1.3.2.2 2004/01/12 23:08:35 keil Exp $
- *
- * Copyright 1997 by Henner Eisen <eis@baty.hanse.de>
- *
- * This software may be used and distributed according to the terms
- * of the GNU General Public License, incorporated herein by reference.
- */
-
-#ifndef _LINUX_CONCAP_H
-#define _LINUX_CONCAP_H
-
-#include <linux/skbuff.h>
-#include <linux/netdevice.h>
-
-/* Stuff to support encapsulation protocols genericly. The encapsulation
-   protocol is processed at the uppermost layer of the network interface.
-
-   Based on a ideas developed in a 'synchronous device' thread in the
-   linux-x25 mailing list contributed by Alan Cox, Thomasz Motylewski
-   and Jonathan Naylor.
-
-   For more documetation on this refer to Documentation/isdn/README.concap
-*/
-
-struct concap_proto_ops;
-struct concap_device_ops;
-
-/* this manages all data needed by the encapsulation protocol
- */
-struct concap_proto{
-	struct net_device *net_dev;	/* net device using our service  */
-	struct concap_device_ops *dops;	/* callbacks provided by device */
- 	struct concap_proto_ops  *pops;	/* callbacks provided by us */
- 	spinlock_t lock;
-	int flags;
-	void *proto_data;		/* protocol specific private data, to
-					   be accessed via *pops methods only*/
-	/*
-	  :
-	  whatever 
-	  :
-	  */
-};
-
-/* Operations to be supported by the net device. Called by the encapsulation
- * protocol entity. No receive method is offered because the encapsulation
- * protocol directly calls netif_rx().
- */
-struct concap_device_ops{
-
-	/* to request data is submitted by device*/ 
-	int (*data_req)(struct concap_proto *, struct sk_buff *);
-
-	/* Control methods must be set to NULL by devices which do not
-	   support connection control.*/
-	/* to request a connection is set up */ 
-	int (*connect_req)(struct concap_proto *);
-
-	/* to request a connection is released */
-	int (*disconn_req)(struct concap_proto *);	
-};
-
-/* Operations to be supported by the encapsulation protocol. Called by
- * device driver.
- */
-struct concap_proto_ops{
-
-	/* create a new encapsulation protocol instance of same type */
-	struct concap_proto *  (*proto_new) (void);
-
-	/* delete encapsulation protocol instance and free all its resources.
-	   cprot may no loger be referenced after calling this */
-	void (*proto_del)(struct concap_proto *cprot);
-
-	/* initialize the protocol's data. To be called at interface startup
-	   or when the device driver resets the interface. All services of the
-	   encapsulation protocol may be used after this*/
-	int (*restart)(struct concap_proto *cprot, 
-		       struct net_device *ndev,
-		       struct concap_device_ops *dops);
-
-	/* inactivate an encapsulation protocol instance. The encapsulation
-	   protocol may not call any *dops methods after this. */
-	int (*close)(struct concap_proto *cprot);
-
-	/* process a frame handed down to us by upper layer */
-	int (*encap_and_xmit)(struct concap_proto *cprot, struct sk_buff *skb);
-
-	/* to be called for each data entity received from lower layer*/ 
-	int (*data_ind)(struct concap_proto *cprot, struct sk_buff *skb);
-
-	/* to be called when a connection was set up/down.
-	   Protocols that don't process these primitives might fill in
-	   dummy methods here */
-	int (*connect_ind)(struct concap_proto *cprot);
-	int (*disconn_ind)(struct concap_proto *cprot);
-  /*
-    Some network device support functions, like net_header(), rebuild_header(),
-    and others, that depend solely on the encapsulation protocol, might
-    be provided here, too. The net device would just fill them in its
-    corresponding fields when it is opened.
-    */
-};
-
-/* dummy restart/close/connect/reset/disconn methods
- */
-extern int concap_nop(struct concap_proto *cprot); 
-
-/* dummy submit method
- */
-extern int concap_drop_skb(struct concap_proto *cprot, struct sk_buff *skb);
-#endif