v4.19.13 snapshot.
diff --git a/include/linux/n_r3964.h b/include/linux/n_r3964.h
new file mode 100644
index 0000000..90a803a
--- /dev/null
+++ b/include/linux/n_r3964.h
@@ -0,0 +1,175 @@
+/* r3964 linediscipline for linux
+ *
+ * -----------------------------------------------------------
+ * Copyright by
+ * Philips Automation Projects
+ * Kassel (Germany)
+ * -----------------------------------------------------------
+ * This software may be used and distributed according to the terms of
+ * the GNU General Public License, incorporated herein by reference.
+ *
+ * Author:
+ * L. Haag
+ *
+ * $Log: r3964.h,v $
+ * Revision 1.4 2005/12/21 19:54:24 Kurt Huwig <kurt huwig de>
+ * Fixed HZ usage on 2.6 kernels
+ * Removed unnecessary include
+ *
+ * Revision 1.3 2001/03/18 13:02:24 dwmw2
+ * Fix timer usage, use spinlocks properly.
+ *
+ * Revision 1.2 2001/03/18 12:53:15 dwmw2
+ * Merge changes in 2.4.2
+ *
+ * Revision 1.1.1.1 1998/10/13 16:43:14 dwmw2
+ * This'll screw the version control
+ *
+ * Revision 1.6 1998/09/30 00:40:38 dwmw2
+ * Updated to use kernel's N_R3964 if available
+ *
+ * Revision 1.4 1998/04/02 20:29:44 lhaag
+ * select, blocking, ...
+ *
+ * Revision 1.3 1998/02/12 18:58:43 root
+ * fixed some memory leaks
+ * calculation of checksum characters
+ *
+ * Revision 1.2 1998/02/07 13:03:17 root
+ * ioctl read_telegram
+ *
+ * Revision 1.1 1998/02/06 19:19:43 root
+ * Initial revision
+ *
+ *
+ */
+#ifndef __LINUX_N_R3964_H__
+#define __LINUX_N_R3964_H__
+
+
+#include <linux/param.h>
+#include <uapi/linux/n_r3964.h>
+
+/*
+ * Common ascii handshake characters:
+ */
+
+#define STX 0x02
+#define ETX 0x03
+#define DLE 0x10
+#define NAK 0x15
+
+/*
+ * Timeouts (from milliseconds to jiffies)
+ */
+
+#define R3964_TO_QVZ ((550)*HZ/1000)
+#define R3964_TO_ZVZ ((220)*HZ/1000)
+#define R3964_TO_NO_BUF ((400)*HZ/1000)
+#define R3964_NO_TX_ROOM ((100)*HZ/1000)
+#define R3964_TO_RX_PANIC ((4000)*HZ/1000)
+#define R3964_MAX_RETRIES 5
+
+
+enum { R3964_IDLE,
+ R3964_TX_REQUEST, R3964_TRANSMITTING,
+ R3964_WAIT_ZVZ_BEFORE_TX_RETRY, R3964_WAIT_FOR_TX_ACK,
+ R3964_WAIT_FOR_RX_BUF,
+ R3964_RECEIVING, R3964_WAIT_FOR_BCC, R3964_WAIT_FOR_RX_REPEAT
+ };
+
+/*
+ * All open file-handles are 'clients' and are stored in a linked list:
+ */
+
+struct r3964_message;
+
+struct r3964_client_info {
+ spinlock_t lock;
+ struct pid *pid;
+ unsigned int sig_flags;
+
+ struct r3964_client_info *next;
+
+ struct r3964_message *first_msg;
+ struct r3964_message *last_msg;
+ struct r3964_block_header *next_block_to_read;
+ int msg_count;
+};
+
+
+
+struct r3964_block_header;
+
+/* internal version of client_message: */
+struct r3964_message {
+ int msg_id;
+ int arg;
+ int error_code;
+ struct r3964_block_header *block;
+ struct r3964_message *next;
+};
+
+/*
+ * Header of received block in rx_buf/tx_buf:
+ */
+
+struct r3964_block_header
+{
+ unsigned int length; /* length in chars without header */
+ unsigned char *data; /* usually data is located
+ immediately behind this struct */
+ unsigned int locks; /* only used in rx_buffer */
+
+ struct r3964_block_header *next;
+ struct r3964_client_info *owner; /* =NULL in rx_buffer */
+};
+
+/*
+ * If rx_buf hasn't enough space to store R3964_MTU chars,
+ * we will reject all incoming STX-requests by sending NAK.
+ */
+
+#define RX_BUF_SIZE 4000
+#define TX_BUF_SIZE 4000
+#define R3964_MAX_BLOCKS_IN_RX_QUEUE 100
+
+#define R3964_PARITY 0x0001
+#define R3964_FRAME 0x0002
+#define R3964_OVERRUN 0x0004
+#define R3964_UNKNOWN 0x0008
+#define R3964_BREAK 0x0010
+#define R3964_CHECKSUM 0x0020
+#define R3964_ERROR 0x003f
+#define R3964_BCC 0x4000
+#define R3964_DEBUG 0x8000
+
+
+struct r3964_info {
+ spinlock_t lock;
+ struct tty_struct *tty;
+ unsigned char priority;
+ unsigned char *rx_buf; /* ring buffer */
+ unsigned char *tx_buf;
+
+ struct r3964_block_header *rx_first;
+ struct r3964_block_header *rx_last;
+ struct r3964_block_header *tx_first;
+ struct r3964_block_header *tx_last;
+ unsigned int tx_position;
+ unsigned int rx_position;
+ unsigned char last_rx;
+ unsigned char bcc;
+ unsigned int blocks_in_rx_queue;
+
+ struct mutex read_lock; /* serialize r3964_read */
+
+ struct r3964_client_info *firstClient;
+ unsigned int state;
+ unsigned int flags;
+
+ struct timer_list tmr;
+ int nRetry;
+};
+
+#endif