net: wan: remove support for COSA and SRP synchronous serial boards

Looks like all the changes to this driver had been automated
churn since git era begun. The driver is using virt_to_bus()
so it should be updated to a proper DMA API or removed. Given
the latest "news" entry on the website is from 1999 I'm opting
for the latter.

I'm marking the allocated char device major number as [REMOVED],
I reckon we can't reuse it in case some SW out there assumes its
COSA?
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/admin-guide/devices.txt

@@ -1933,7 +1933,7 @@
 		    ...
 		255= /dev/umem/d15p15  15th partition of 16th board.
 
- 117 char	COSA/SRP synchronous serial card
+ 117 char	[REMOVED] COSA/SRP synchronous serial card
 		  0 = /dev/cosa0c0	1st board, 1st channel
 		  1 = /dev/cosa0c1	1st board, 2nd channel
 		    ...

MAINTAINERS

@@ -5047,12 +5047,6 @@ S:	Maintained
 F:	Documentation/hwmon/corsair-psu.rst
 F:	drivers/hwmon/corsair-psu.c
 
-COSA/SRP SYNC SERIAL DRIVER
-M:	Jan "Yenya" Kasprzak <kas@fi.muni.cz>
-S:	Maintained
-W:	http://www.fi.muni.cz/~kas/cosa/
-F:	drivers/net/wan/cosa*
-
 COUNTER SUBSYSTEM
 M:	William Breathitt Gray <vilhelm.gray@gmail.com>
 L:	linux-iio@vger.kernel.org

drivers/net/wan/Kconfig

@@ -35,28 +35,6 @@ config HOSTESS_SV11
 	  The driver will be compiled as a module: the
 	  module will be called hostess_sv11.
 
-# The COSA/SRP driver has not been tested as non-modular yet.
-config COSA
-	tristate "COSA/SRP sync serial boards support"
-	depends on ISA && m && ISA_DMA_API && HDLC && VIRT_TO_BUS
-	help
-	  Driver for COSA and SRP synchronous serial boards.
-
-	  These boards allow to connect synchronous serial devices (for example
-	  base-band modems, or any other device with the X.21, V.24, V.35 or
-	  V.36 interface) to your Linux box. The cards can work as the
-	  character device, synchronous PPP network device, or the Cisco HDLC
-	  network device.
-
-	  You will need user-space utilities COSA or SRP boards for downloading
-	  the firmware to the cards and to set them up. Look at the
-	  <http://www.fi.muni.cz/~kas/cosa/> for more information. You can also
-	  read the comment at the top of the <file:drivers/net/wan/cosa.c> for
-	  details about the cards and the driver itself.
-
-	  The driver will be compiled as a module: the
-	  module will be called cosa.
-
 # There is no way to detect a Sealevel board. Force it modular
 config SEALEVEL_4021
 	tristate "Sealevel Systems 4021 support"

drivers/net/wan/Makefile

@@ -16,7 +16,6 @@ obj-$(CONFIG_HDLC_X25)		+= hdlc_x25.o
 
 obj-$(CONFIG_HOSTESS_SV11)	+= z85230.o	hostess_sv11.o
 obj-$(CONFIG_SEALEVEL_4021)	+= z85230.o	sealevel.o
-obj-$(CONFIG_COSA)		+= cosa.o
 obj-$(CONFIG_FARSYNC)		+= farsync.o
 
 obj-$(CONFIG_LAPBETHER)		+= lapbether.o

drivers/net/wan/cosa.h

-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/* $Id: cosa.h,v 1.6 1999/01/06 14:02:44 kas Exp $ */
-
-/*
- *  Copyright (C) 1995-1997  Jan "Yenya" Kasprzak <kas@fi.muni.cz>
- */
-
-#ifndef COSA_H__
-#define COSA_H__
-
-#include <linux/ioctl.h>
-
-#ifdef __KERNEL__
-/* status register - output bits */
-#define SR_RX_DMA_ENA   0x04    /* receiver DMA enable bit */
-#define SR_TX_DMA_ENA   0x08    /* transmitter DMA enable bit */
-#define SR_RST          0x10    /* SRP reset */
-#define SR_USR_INT_ENA  0x20    /* user interrupt enable bit */
-#define SR_TX_INT_ENA   0x40    /* transmitter interrupt enable bit */
-#define SR_RX_INT_ENA   0x80    /* receiver interrupt enable bit */
-
-/* status register - input bits */
-#define SR_USR_RQ       0x20    /* user interrupt request pending */
-#define SR_TX_RDY       0x40    /* transmitter empty (ready) */
-#define SR_RX_RDY       0x80    /* receiver data ready */
-
-#define SR_UP_REQUEST   0x02    /* request from SRP to transfer data
-                                   up to PC */
-#define SR_DOWN_REQUEST 0x01    /* SRP is able to transfer data down
-                                   from PC to SRP */
-#define SR_END_OF_TRANSFER      0x03    /* SRP signalize end of
-                                           transfer (up or down) */
-
-#define SR_CMD_FROM_SRP_MASK    0x03    /* mask to get SRP command */
-
-/* bits in driver status byte definitions : */
-#define SR_RDY_RCV      0x01    /* ready to receive packet */
-#define SR_RDY_SND      0x02    /* ready to send packet */
-#define SR_CMD_PND      0x04    /* command pending */ /* not currently used */
-
-/* ???? */
-#define SR_PKT_UP       0x01    /* transfer of packet up in progress */
-#define SR_PKT_DOWN     0x02    /* transfer of packet down in progress */
-
-#endif /* __KERNEL__ */
-
-#define SR_LOAD_ADDR    0x4400  /* SRP microcode load address */
-#define SR_START_ADDR   0x4400  /* SRP microcode start address */
-
-#define COSA_LOAD_ADDR    0x400  /* SRP microcode load address */
-#define COSA_MAX_FIRMWARE_SIZE	0x10000
-
-/* ioctls */
-struct cosa_download {
-	int addr, len;
-	char __user *code;
-};
-
-/* Reset the device */
-#define COSAIORSET	_IO('C',0xf0)
-
-/* Start microcode at given address */
-#define COSAIOSTRT	_IOW('C',0xf1, int)
-
-/* Read the block from the device memory */
-#define COSAIORMEM	_IOWR('C',0xf2, struct cosa_download *)
-	/* actually the struct cosa_download itself; this is to keep
-	 * the ioctl number same as in 2.4 in order to keep the user-space
-	 * utils compatible. */
-
-/* Write the block to the device memory (i.e. download the microcode) */
-#define COSAIODOWNLD	_IOW('C',0xf2, struct cosa_download *)
-	/* actually the struct cosa_download itself; this is to keep
-	 * the ioctl number same as in 2.4 in order to keep the user-space
-	 * utils compatible. */
-
-/* Read the device type (one of "srp", "cosa", and "cosa8" for now) */
-#define COSAIORTYPE	_IOR('C',0xf3, char *)
-
-/* Read the device identification string */
-#define COSAIORIDSTR	_IOR('C',0xf4, char *)
-/* Maximum length of the identification string. */
-#define COSA_MAX_ID_STRING 128
-
-/* Increment/decrement the module usage count :-) */
-/* #define COSAIOMINC	_IO('C',0xf5) */
-/* #define COSAIOMDEC	_IO('C',0xf6) */
-
-/* Get the total number of cards installed */
-#define COSAIONRCARDS	_IO('C',0xf7)
-
-/* Get the number of channels on this card */
-#define COSAIONRCHANS	_IO('C',0xf8)
-
-/* Set the driver for the bus-master operations */
-#define COSAIOBMSET	_IOW('C', 0xf9, unsigned short)
-
-#define COSA_BM_OFF	0	/* Bus-mastering off - use ISA DMA (default) */
-#define COSA_BM_ON	1	/* Bus-mastering on - faster but untested */
-
-/* Gets the busmaster status */
-#define COSAIOBMGET	_IO('C', 0xfa)
-
-#endif /* !COSA_H__ */