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, 357 deletions

diff --git a/drivers/isdn/hysdn/hysdn_proclog.c b/drivers/isdn/hysdn/hysdn_proclog.c
deleted file mode 100644
index 6e898b90e86e..000000000000
--- a/drivers/isdn/hysdn/hysdn_proclog.c
+++ /dev/null
@@ -1,357 +0,0 @@
-/* $Id: hysdn_proclog.c,v 1.9.6.3 2001/09/23 22:24:54 kai Exp $
- *
- * Linux driver for HYSDN cards, /proc/net filesystem log functions.
- *
- * Author    Werner Cornelius (werner@titro.de) for Hypercope GmbH
- * Copyright 1999 by Werner Cornelius (werner@titro.de)
- *
- * This software may be used and distributed according to the terms
- * of the GNU General Public License, incorporated herein by reference.
- *
- */
-
-#include <linux/module.h>
-#include <linux/poll.h>
-#include <linux/proc_fs.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/mutex.h>
-#include <linux/kernel.h>
-
-#include "hysdn_defs.h"
-
-/* the proc subdir for the interface is defined in the procconf module */
-extern struct proc_dir_entry *hysdn_proc_entry;
-
-static DEFINE_MUTEX(hysdn_log_mutex);
-static void put_log_buffer(hysdn_card *card, char *cp);
-
-/*************************************************/
-/* structure keeping ascii log for device output */
-/*************************************************/
-struct log_data {
-	struct log_data *next;
-	unsigned long usage_cnt;/* number of files still to work */
-	void *proc_ctrl;	/* pointer to own control procdata structure */
-	char log_start[2];	/* log string start (final len aligned by size) */
-};
-
-/**********************************************/
-/* structure holding proc entrys for one card */
-/**********************************************/
-struct procdata {
-	struct proc_dir_entry *log;	/* log entry */
-	char log_name[15];	/* log filename */
-	struct log_data *log_head, *log_tail;	/* head and tail for queue */
-	int if_used;		/* open count for interface */
-	unsigned char logtmp[LOG_MAX_LINELEN];
-	wait_queue_head_t rd_queue;
-};
-
-
-/**********************************************/
-/* log function for cards error log interface */
-/**********************************************/
-void
-hysdn_card_errlog(hysdn_card *card, tErrLogEntry *logp, int maxsize)
-{
-	char buf[ERRLOG_TEXT_SIZE + 40];
-
-	sprintf(buf, "LOG 0x%08lX 0x%08lX : %s\n", logp->ulErrType, logp->ulErrSubtype, logp->ucText);
-	put_log_buffer(card, buf);	/* output the string */
-}				/* hysdn_card_errlog */
-
-/***************************************************/
-/* Log function using format specifiers for output */
-/***************************************************/
-void
-hysdn_addlog(hysdn_card *card, char *fmt, ...)
-{
-	struct procdata *pd = card->proclog;
-	char *cp;
-	va_list args;
-
-	if (!pd)
-		return;		/* log structure non existent */
-
-	cp = pd->logtmp;
-	cp += sprintf(cp, "HYSDN: card %d ", card->myid);
-
-	va_start(args, fmt);
-	cp += vsprintf(cp, fmt, args);
-	va_end(args);
-	*cp++ = '\n';
-	*cp = 0;
-
-	if (card->debug_flags & DEB_OUT_SYSLOG)
-		printk(KERN_INFO "%s", pd->logtmp);
-	else
-		put_log_buffer(card, pd->logtmp);
-
-}				/* hysdn_addlog */
-
-/********************************************/
-/* put an log buffer into the log queue.    */
-/* This buffer will be kept until all files */
-/* opened for read got the contents.        */
-/* Flushes buffers not longer in use.       */
-/********************************************/
-static void
-put_log_buffer(hysdn_card *card, char *cp)
-{
-	struct log_data *ib;
-	struct procdata *pd = card->proclog;
-	unsigned long flags;
-
-	if (!pd)
-		return;
-	if (!cp)
-		return;
-	if (!*cp)
-		return;
-	if (pd->if_used <= 0)
-		return;		/* no open file for read */
-
-	if (!(ib = kmalloc(sizeof(struct log_data) + strlen(cp), GFP_ATOMIC)))
-		return;	/* no memory */
-	strcpy(ib->log_start, cp);	/* set output string */
-	ib->next = NULL;
-	ib->proc_ctrl = pd;	/* point to own control structure */
-	spin_lock_irqsave(&card->hysdn_lock, flags);
-	ib->usage_cnt = pd->if_used;
-	if (!pd->log_head)
-		pd->log_head = ib;	/* new head */
-	else
-		pd->log_tail->next = ib;	/* follows existing messages */
-	pd->log_tail = ib;	/* new tail */
-
-	/* delete old entrys */
-	while (pd->log_head->next) {
-		if ((pd->log_head->usage_cnt <= 0) &&
-		    (pd->log_head->next->usage_cnt <= 0)) {
-			ib = pd->log_head;
-			pd->log_head = pd->log_head->next;
-			kfree(ib);
-		} else {
-			break;
-		}
-	}		/* pd->log_head->next */
-
-	spin_unlock_irqrestore(&card->hysdn_lock, flags);
-
-	wake_up_interruptible(&(pd->rd_queue));		/* announce new entry */
-}				/* put_log_buffer */
-
-
-/******************************/
-/* file operations and tables */
-/******************************/
-
-/****************************************/
-/* write log file -> set log level bits */
-/****************************************/
-static ssize_t
-hysdn_log_write(struct file *file, const char __user *buf, size_t count, loff_t *off)
-{
-	int rc;
-	hysdn_card *card = file->private_data;
-
-	rc = kstrtoul_from_user(buf, count, 0, &card->debug_flags);
-	if (rc < 0)
-		return rc;
-	hysdn_addlog(card, "debug set to 0x%lx", card->debug_flags);
-	return (count);
-}				/* hysdn_log_write */
-
-/******************/
-/* read log file */
-/******************/
-static ssize_t
-hysdn_log_read(struct file *file, char __user *buf, size_t count, loff_t *off)
-{
-	struct log_data *inf;
-	int len;
-	hysdn_card *card = PDE_DATA(file_inode(file));
-
-	if (!(inf = *((struct log_data **) file->private_data))) {
-		struct procdata *pd = card->proclog;
-		if (file->f_flags & O_NONBLOCK)
-			return (-EAGAIN);
-
-		wait_event_interruptible(pd->rd_queue, (inf =
-				*((struct log_data **) file->private_data)));
-	}
-	if (!inf)
-		return (0);
-
-	inf->usage_cnt--;	/* new usage count */
-	file->private_data = &inf->next;	/* next structure */
-	if ((len = strlen(inf->log_start)) <= count) {
-		if (copy_to_user(buf, inf->log_start, len))
-			return -EFAULT;
-		*off += len;
-		return (len);
-	}
-	return (0);
-}				/* hysdn_log_read */
-
-/******************/
-/* open log file */
-/******************/
-static int
-hysdn_log_open(struct inode *ino, struct file *filep)
-{
-	hysdn_card *card = PDE_DATA(ino);
-
-	mutex_lock(&hysdn_log_mutex);
-	if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
-		/* write only access -> write log level only */
-		filep->private_data = card;	/* remember our own card */
-	} else if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_READ) {
-		struct procdata *pd = card->proclog;
-		unsigned long flags;
-
-		/* read access -> log/debug read */
-		spin_lock_irqsave(&card->hysdn_lock, flags);
-		pd->if_used++;
-		if (pd->log_head)
-			filep->private_data = &pd->log_tail->next;
-		else
-			filep->private_data = &pd->log_head;
-		spin_unlock_irqrestore(&card->hysdn_lock, flags);
-	} else {		/* simultaneous read/write access forbidden ! */
-		mutex_unlock(&hysdn_log_mutex);
-		return (-EPERM);	/* no permission this time */
-	}
-	mutex_unlock(&hysdn_log_mutex);
-	return nonseekable_open(ino, filep);
-}				/* hysdn_log_open */
-
-/*******************************************************************************/
-/* close a cardlog file. If the file has been opened for exclusive write it is */
-/* assumed as pof data input and the pof loader is noticed about.              */
-/* Otherwise file is handled as log output. In this case the interface usage   */
-/* count is decremented and all buffers are noticed of closing. If this file   */
-/* was the last one to be closed, all buffers are freed.                       */
-/*******************************************************************************/
-static int
-hysdn_log_close(struct inode *ino, struct file *filep)
-{
-	struct log_data *inf;
-	struct procdata *pd;
-	hysdn_card *card;
-	int retval = 0;
-
-	mutex_lock(&hysdn_log_mutex);
-	if ((filep->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE) {
-		/* write only access -> write debug level written */
-		retval = 0;	/* success */
-	} else {
-		/* read access -> log/debug read, mark one further file as closed */
-
-		inf = *((struct log_data **) filep->private_data);	/* get first log entry */
-		if (inf)
-			pd = (struct procdata *) inf->proc_ctrl;	/* still entries there */
-		else {
-			/* no info available -> search card */
-			card = PDE_DATA(file_inode(filep));
-			pd = card->proclog;	/* pointer to procfs log */
-		}
-		if (pd)
-			pd->if_used--;	/* decrement interface usage count by one */
-
-		while (inf) {
-			inf->usage_cnt--;	/* decrement usage count for buffers */
-			inf = inf->next;
-		}
-
-		if (pd)
-			if (pd->if_used <= 0)	/* delete buffers if last file closed */
-				while (pd->log_head) {
-					inf = pd->log_head;
-					pd->log_head = pd->log_head->next;
-					kfree(inf);
-				}
-	}			/* read access */
-	mutex_unlock(&hysdn_log_mutex);
-
-	return (retval);
-}				/* hysdn_log_close */
-
-/*************************************************/
-/* select/poll routine to be able using select() */
-/*************************************************/
-static __poll_t
-hysdn_log_poll(struct file *file, poll_table *wait)
-{
-	__poll_t mask = 0;
-	hysdn_card *card = PDE_DATA(file_inode(file));
-	struct procdata *pd = card->proclog;
-
-	if ((file->f_mode & (FMODE_READ | FMODE_WRITE)) == FMODE_WRITE)
-		return (mask);	/* no polling for write supported */
-
-	poll_wait(file, &(pd->rd_queue), wait);
-
-	if (*((struct log_data **) file->private_data))
-		mask |= EPOLLIN | EPOLLRDNORM;
-
-	return mask;
-}				/* hysdn_log_poll */
-
-/**************************************************/
-/* table for log filesystem functions defined above. */
-/**************************************************/
-static const struct file_operations log_fops =
-{
-	.owner		= THIS_MODULE,
-	.llseek         = no_llseek,
-	.read           = hysdn_log_read,
-	.write          = hysdn_log_write,
-	.poll           = hysdn_log_poll,
-	.open           = hysdn_log_open,
-	.release        = hysdn_log_close,
-};
-
-
-/***********************************************************************************/
-/* hysdn_proclog_init is called when the module is loaded after creating the cards */
-/* conf files.                                                                     */
-/***********************************************************************************/
-int
-hysdn_proclog_init(hysdn_card *card)
-{
-	struct procdata *pd;
-
-	/* create a cardlog proc entry */
-
-	if ((pd = kzalloc(sizeof(struct procdata), GFP_KERNEL)) != NULL) {
-		sprintf(pd->log_name, "%s%d", PROC_LOG_BASENAME, card->myid);
-		pd->log = proc_create_data(pd->log_name,
-				      S_IFREG | S_IRUGO | S_IWUSR, hysdn_proc_entry,
-				      &log_fops, card);
-
-		init_waitqueue_head(&(pd->rd_queue));
-
-		card->proclog = (void *) pd;	/* remember procfs structure */
-	}
-	return (0);
-}				/* hysdn_proclog_init */
-
-/************************************************************************************/
-/* hysdn_proclog_release is called when the module is unloaded and before the cards */
-/* conf file is released                                                            */
-/* The module counter is assumed to be 0 !                                          */
-/************************************************************************************/
-void
-hysdn_proclog_release(hysdn_card *card)
-{
-	struct procdata *pd;
-
-	if ((pd = (struct procdata *) card->proclog) != NULL) {
-		if (pd->log)
-			remove_proc_entry(pd->log_name, hysdn_proc_entry);
-		kfree(pd);	/* release memory */
-		card->proclog = NULL;
-	}
-}				/* hysdn_proclog_release */