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1284 lines
31 KiB
1284 lines
31 KiB
// SPDX-License-Identifier: GPL-1.0+ |
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/* r3964 linediscipline for linux |
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* |
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* ----------------------------------------------------------- |
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* Copyright by |
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* Philips Automation Projects |
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* Kassel (Germany) |
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* ----------------------------------------------------------- |
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* Author: |
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* L. Haag |
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* |
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* $Log: n_r3964.c,v $ |
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* Revision 1.10 2001/03/18 13:02:24 dwmw2 |
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* Fix timer usage, use spinlocks properly. |
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* |
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* Revision 1.9 2001/03/18 12:52:14 dwmw2 |
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* Merge changes in 2.4.2 |
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* |
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* Revision 1.8 2000/03/23 14:14:54 dwmw2 |
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* Fix race in sleeping in r3964_read() |
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* |
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* Revision 1.7 1999/28/08 11:41:50 dwmw2 |
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* Port to 2.3 kernel |
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* |
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* Revision 1.6 1998/09/30 00:40:40 dwmw2 |
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* Fixed compilation on 2.0.x kernels |
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* Updated to newly registered tty-ldisc number 9 |
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* |
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* Revision 1.5 1998/09/04 21:57:36 dwmw2 |
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* Signal handling bug fixes, port to 2.1.x. |
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* |
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* Revision 1.4 1998/04/02 20:26:59 lhaag |
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* select, blocking, ... |
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* |
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* Revision 1.3 1998/02/12 18:58:43 root |
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* fixed some memory leaks |
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* calculation of checksum characters |
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* |
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* Revision 1.2 1998/02/07 13:03:34 root |
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* ioctl read_telegram |
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* |
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* Revision 1.1 1998/02/06 19:21:03 root |
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* Initial revision |
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* |
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* |
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*/ |
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|
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#include <linux/module.h> |
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#include <linux/kernel.h> |
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#include <linux/sched.h> |
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#include <linux/types.h> |
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#include <linux/fcntl.h> |
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#include <linux/interrupt.h> |
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#include <linux/ptrace.h> |
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#include <linux/ioport.h> |
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#include <linux/in.h> |
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#include <linux/slab.h> |
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#include <linux/tty.h> |
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#include <linux/errno.h> |
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#include <linux/string.h> /* used in new tty drivers */ |
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#include <linux/signal.h> /* used in new tty drivers */ |
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#include <linux/ioctl.h> |
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#include <linux/n_r3964.h> |
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#include <linux/poll.h> |
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#include <linux/init.h> |
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#include <linux/uaccess.h> |
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|
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/*#define DEBUG_QUEUE*/ |
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|
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/* Log successful handshake and protocol operations */ |
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/*#define DEBUG_PROTO_S*/ |
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|
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/* Log handshake and protocol errors: */ |
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/*#define DEBUG_PROTO_E*/ |
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|
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/* Log Linediscipline operations (open, close, read, write...): */ |
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/*#define DEBUG_LDISC*/ |
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|
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/* Log module and memory operations (init, cleanup; kmalloc, kfree): */ |
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/*#define DEBUG_MODUL*/ |
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|
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/* Macro helpers for debug output: */ |
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#define TRACE(format, args...) printk("r3964: " format "\n" , ## args) |
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|
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#ifdef DEBUG_MODUL |
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#define TRACE_M(format, args...) printk("r3964: " format "\n" , ## args) |
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#else |
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#define TRACE_M(fmt, arg...) do {} while (0) |
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#endif |
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#ifdef DEBUG_PROTO_S |
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#define TRACE_PS(format, args...) printk("r3964: " format "\n" , ## args) |
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#else |
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#define TRACE_PS(fmt, arg...) do {} while (0) |
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#endif |
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#ifdef DEBUG_PROTO_E |
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#define TRACE_PE(format, args...) printk("r3964: " format "\n" , ## args) |
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#else |
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#define TRACE_PE(fmt, arg...) do {} while (0) |
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#endif |
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#ifdef DEBUG_LDISC |
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#define TRACE_L(format, args...) printk("r3964: " format "\n" , ## args) |
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#else |
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#define TRACE_L(fmt, arg...) do {} while (0) |
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#endif |
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#ifdef DEBUG_QUEUE |
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#define TRACE_Q(format, args...) printk("r3964: " format "\n" , ## args) |
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#else |
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#define TRACE_Q(fmt, arg...) do {} while (0) |
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#endif |
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static void add_tx_queue(struct r3964_info *, struct r3964_block_header *); |
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static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code); |
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static void put_char(struct r3964_info *pInfo, unsigned char ch); |
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static void trigger_transmit(struct r3964_info *pInfo); |
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static void retry_transmit(struct r3964_info *pInfo); |
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static void transmit_block(struct r3964_info *pInfo); |
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static void receive_char(struct r3964_info *pInfo, const unsigned char c); |
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static void receive_error(struct r3964_info *pInfo, const char flag); |
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static void on_timeout(struct timer_list *t); |
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static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg); |
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static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
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unsigned char __user * buf); |
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static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
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int error_code, struct r3964_block_header *pBlock); |
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static struct r3964_message *remove_msg(struct r3964_info *pInfo, |
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struct r3964_client_info *pClient); |
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static void remove_client_block(struct r3964_info *pInfo, |
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struct r3964_client_info *pClient); |
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|
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static int r3964_open(struct tty_struct *tty); |
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static void r3964_close(struct tty_struct *tty); |
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static ssize_t r3964_read(struct tty_struct *tty, struct file *file, |
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void *cookie, unsigned char *buf, size_t nr); |
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static ssize_t r3964_write(struct tty_struct *tty, struct file *file, |
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const unsigned char *buf, size_t nr); |
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static int r3964_ioctl(struct tty_struct *tty, struct file *file, |
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unsigned int cmd, unsigned long arg); |
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#ifdef CONFIG_COMPAT |
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static int r3964_compat_ioctl(struct tty_struct *tty, struct file *file, |
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unsigned int cmd, unsigned long arg); |
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#endif |
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static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old); |
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static __poll_t r3964_poll(struct tty_struct *tty, struct file *file, |
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struct poll_table_struct *wait); |
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static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
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char *fp, int count); |
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|
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static struct tty_ldisc_ops tty_ldisc_N_R3964 = { |
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.owner = THIS_MODULE, |
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.magic = TTY_LDISC_MAGIC, |
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.name = "R3964", |
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.open = r3964_open, |
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.close = r3964_close, |
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.read = r3964_read, |
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.write = r3964_write, |
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.ioctl = r3964_ioctl, |
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#ifdef CONFIG_COMPAT |
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.compat_ioctl = r3964_compat_ioctl, |
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#endif |
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.set_termios = r3964_set_termios, |
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.poll = r3964_poll, |
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.receive_buf = r3964_receive_buf, |
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}; |
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|
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static void dump_block(const unsigned char *block, unsigned int length) |
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{ |
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unsigned int i, j; |
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char linebuf[16 * 3 + 1]; |
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|
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for (i = 0; i < length; i += 16) { |
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for (j = 0; (j < 16) && (j + i < length); j++) { |
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sprintf(linebuf + 3 * j, "%02x ", block[i + j]); |
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} |
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linebuf[3 * j] = '\0'; |
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TRACE_PS("%s", linebuf); |
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} |
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} |
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|
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/************************************************************* |
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* Driver initialisation |
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*************************************************************/ |
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|
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/************************************************************* |
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* Module support routines |
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*************************************************************/ |
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|
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static void __exit r3964_exit(void) |
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{ |
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int status; |
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|
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TRACE_M("cleanup_module()"); |
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status = tty_unregister_ldisc(N_R3964); |
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if (status != 0) { |
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printk(KERN_ERR "r3964: error unregistering linediscipline: " |
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"%d\n", status); |
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} else { |
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TRACE_L("linediscipline successfully unregistered"); |
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} |
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} |
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|
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static int __init r3964_init(void) |
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{ |
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int status; |
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|
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printk("r3964: Philips r3964 Driver $Revision: 1.10 $\n"); |
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|
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/* |
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* Register the tty line discipline |
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*/ |
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status = tty_register_ldisc(N_R3964, &tty_ldisc_N_R3964); |
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if (status == 0) { |
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TRACE_L("line discipline %d registered", N_R3964); |
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TRACE_L("flags=%x num=%x", tty_ldisc_N_R3964.flags, |
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tty_ldisc_N_R3964.num); |
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TRACE_L("open=%p", tty_ldisc_N_R3964.open); |
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TRACE_L("tty_ldisc_N_R3964 = %p", &tty_ldisc_N_R3964); |
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} else { |
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printk(KERN_ERR "r3964: error registering line discipline: " |
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"%d\n", status); |
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} |
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return status; |
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} |
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|
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module_init(r3964_init); |
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module_exit(r3964_exit); |
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|
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/************************************************************* |
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* Protocol implementation routines |
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*************************************************************/ |
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static void add_tx_queue(struct r3964_info *pInfo, |
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struct r3964_block_header *pHeader) |
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{ |
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unsigned long flags; |
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spin_lock_irqsave(&pInfo->lock, flags); |
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pHeader->next = NULL; |
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if (pInfo->tx_last == NULL) { |
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pInfo->tx_first = pInfo->tx_last = pHeader; |
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} else { |
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pInfo->tx_last->next = pHeader; |
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pInfo->tx_last = pHeader; |
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} |
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spin_unlock_irqrestore(&pInfo->lock, flags); |
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TRACE_Q("add_tx_queue %p, length %d, tx_first = %p", |
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pHeader, pHeader->length, pInfo->tx_first); |
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} |
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static void remove_from_tx_queue(struct r3964_info *pInfo, int error_code) |
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{ |
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struct r3964_block_header *pHeader; |
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unsigned long flags; |
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#ifdef DEBUG_QUEUE |
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struct r3964_block_header *pDump; |
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#endif |
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pHeader = pInfo->tx_first; |
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|
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if (pHeader == NULL) |
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return; |
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|
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#ifdef DEBUG_QUEUE |
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printk("r3964: remove_from_tx_queue: %p, length %u - ", |
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pHeader, pHeader->length); |
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for (pDump = pHeader; pDump; pDump = pDump->next) |
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printk("%p ", pDump); |
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printk("\n"); |
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#endif |
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if (pHeader->owner) { |
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if (error_code) { |
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add_msg(pHeader->owner, R3964_MSG_ACK, 0, |
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error_code, NULL); |
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} else { |
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add_msg(pHeader->owner, R3964_MSG_ACK, pHeader->length, |
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error_code, NULL); |
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} |
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wake_up_interruptible(&pInfo->tty->read_wait); |
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} |
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spin_lock_irqsave(&pInfo->lock, flags); |
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pInfo->tx_first = pHeader->next; |
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if (pInfo->tx_first == NULL) { |
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pInfo->tx_last = NULL; |
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} |
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spin_unlock_irqrestore(&pInfo->lock, flags); |
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kfree(pHeader); |
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TRACE_M("remove_from_tx_queue - kfree %p", pHeader); |
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TRACE_Q("remove_from_tx_queue: tx_first = %p, tx_last = %p", |
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pInfo->tx_first, pInfo->tx_last); |
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} |
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static void add_rx_queue(struct r3964_info *pInfo, |
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struct r3964_block_header *pHeader) |
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{ |
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unsigned long flags; |
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spin_lock_irqsave(&pInfo->lock, flags); |
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pHeader->next = NULL; |
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if (pInfo->rx_last == NULL) { |
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pInfo->rx_first = pInfo->rx_last = pHeader; |
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} else { |
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pInfo->rx_last->next = pHeader; |
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pInfo->rx_last = pHeader; |
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} |
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pInfo->blocks_in_rx_queue++; |
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spin_unlock_irqrestore(&pInfo->lock, flags); |
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TRACE_Q("add_rx_queue: %p, length = %d, rx_first = %p, count = %d", |
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pHeader, pHeader->length, |
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pInfo->rx_first, pInfo->blocks_in_rx_queue); |
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} |
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static void remove_from_rx_queue(struct r3964_info *pInfo, |
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struct r3964_block_header *pHeader) |
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{ |
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unsigned long flags; |
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struct r3964_block_header *pFind; |
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if (pHeader == NULL) |
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return; |
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|
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TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", |
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pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); |
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TRACE_Q("remove_from_rx_queue: %p, length %u", |
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pHeader, pHeader->length); |
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spin_lock_irqsave(&pInfo->lock, flags); |
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if (pInfo->rx_first == pHeader) { |
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/* Remove the first block in the linked list: */ |
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pInfo->rx_first = pHeader->next; |
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|
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if (pInfo->rx_first == NULL) { |
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pInfo->rx_last = NULL; |
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} |
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pInfo->blocks_in_rx_queue--; |
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} else { |
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/* Find block to remove: */ |
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for (pFind = pInfo->rx_first; pFind; pFind = pFind->next) { |
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if (pFind->next == pHeader) { |
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/* Got it. */ |
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pFind->next = pHeader->next; |
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pInfo->blocks_in_rx_queue--; |
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if (pFind->next == NULL) { |
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/* Oh, removed the last one! */ |
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pInfo->rx_last = pFind; |
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} |
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break; |
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} |
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} |
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} |
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spin_unlock_irqrestore(&pInfo->lock, flags); |
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|
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kfree(pHeader); |
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TRACE_M("remove_from_rx_queue - kfree %p", pHeader); |
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|
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TRACE_Q("remove_from_rx_queue: rx_first = %p, rx_last = %p, count = %d", |
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pInfo->rx_first, pInfo->rx_last, pInfo->blocks_in_rx_queue); |
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} |
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|
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static void put_char(struct r3964_info *pInfo, unsigned char ch) |
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{ |
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struct tty_struct *tty = pInfo->tty; |
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/* FIXME: put_char should not be called from an IRQ */ |
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tty_put_char(tty, ch); |
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pInfo->bcc ^= ch; |
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} |
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|
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static void flush(struct r3964_info *pInfo) |
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{ |
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struct tty_struct *tty = pInfo->tty; |
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|
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if (tty == NULL || tty->ops->flush_chars == NULL) |
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return; |
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tty->ops->flush_chars(tty); |
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} |
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|
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static void trigger_transmit(struct r3964_info *pInfo) |
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{ |
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unsigned long flags; |
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|
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spin_lock_irqsave(&pInfo->lock, flags); |
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|
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if ((pInfo->state == R3964_IDLE) && (pInfo->tx_first != NULL)) { |
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pInfo->state = R3964_TX_REQUEST; |
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pInfo->nRetry = 0; |
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pInfo->flags &= ~R3964_ERROR; |
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mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); |
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spin_unlock_irqrestore(&pInfo->lock, flags); |
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|
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TRACE_PS("trigger_transmit - sent STX"); |
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put_char(pInfo, STX); |
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flush(pInfo); |
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|
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pInfo->bcc = 0; |
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} else { |
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spin_unlock_irqrestore(&pInfo->lock, flags); |
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} |
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} |
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|
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static void retry_transmit(struct r3964_info *pInfo) |
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{ |
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if (pInfo->nRetry < R3964_MAX_RETRIES) { |
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TRACE_PE("transmission failed. Retry #%d", pInfo->nRetry); |
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pInfo->bcc = 0; |
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put_char(pInfo, STX); |
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flush(pInfo); |
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pInfo->state = R3964_TX_REQUEST; |
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pInfo->nRetry++; |
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mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); |
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} else { |
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TRACE_PE("transmission failed after %d retries", |
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R3964_MAX_RETRIES); |
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|
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remove_from_tx_queue(pInfo, R3964_TX_FAIL); |
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|
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put_char(pInfo, NAK); |
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flush(pInfo); |
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pInfo->state = R3964_IDLE; |
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|
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trigger_transmit(pInfo); |
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} |
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} |
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|
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static void transmit_block(struct r3964_info *pInfo) |
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{ |
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struct tty_struct *tty = pInfo->tty; |
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struct r3964_block_header *pBlock = pInfo->tx_first; |
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int room = 0; |
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|
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if (tty == NULL || pBlock == NULL) { |
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return; |
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} |
|
|
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room = tty_write_room(tty); |
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|
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TRACE_PS("transmit_block %p, room %d, length %d", |
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pBlock, room, pBlock->length); |
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|
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while (pInfo->tx_position < pBlock->length) { |
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if (room < 2) |
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break; |
|
|
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if (pBlock->data[pInfo->tx_position] == DLE) { |
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/* send additional DLE char: */ |
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put_char(pInfo, DLE); |
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} |
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put_char(pInfo, pBlock->data[pInfo->tx_position++]); |
|
|
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room--; |
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} |
|
|
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if ((pInfo->tx_position == pBlock->length) && (room >= 3)) { |
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put_char(pInfo, DLE); |
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put_char(pInfo, ETX); |
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if (pInfo->flags & R3964_BCC) { |
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put_char(pInfo, pInfo->bcc); |
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} |
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pInfo->state = R3964_WAIT_FOR_TX_ACK; |
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mod_timer(&pInfo->tmr, jiffies + R3964_TO_QVZ); |
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} |
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flush(pInfo); |
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} |
|
|
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static void on_receive_block(struct r3964_info *pInfo) |
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{ |
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unsigned int length; |
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struct r3964_client_info *pClient; |
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struct r3964_block_header *pBlock; |
|
|
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length = pInfo->rx_position; |
|
|
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/* compare byte checksum characters: */ |
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if (pInfo->flags & R3964_BCC) { |
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if (pInfo->bcc != pInfo->last_rx) { |
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TRACE_PE("checksum error - got %x but expected %x", |
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pInfo->last_rx, pInfo->bcc); |
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pInfo->flags |= R3964_CHECKSUM; |
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} |
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} |
|
|
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/* check for errors (parity, overrun,...): */ |
|
if (pInfo->flags & R3964_ERROR) { |
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TRACE_PE("on_receive_block - transmission failed error %x", |
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pInfo->flags & R3964_ERROR); |
|
|
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put_char(pInfo, NAK); |
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flush(pInfo); |
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if (pInfo->nRetry < R3964_MAX_RETRIES) { |
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pInfo->state = R3964_WAIT_FOR_RX_REPEAT; |
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pInfo->nRetry++; |
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mod_timer(&pInfo->tmr, jiffies + R3964_TO_RX_PANIC); |
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} else { |
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TRACE_PE("on_receive_block - failed after max retries"); |
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pInfo->state = R3964_IDLE; |
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} |
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return; |
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} |
|
|
|
/* received block; submit DLE: */ |
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put_char(pInfo, DLE); |
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flush(pInfo); |
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del_timer_sync(&pInfo->tmr); |
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TRACE_PS(" rx success: got %d chars", length); |
|
|
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/* prepare struct r3964_block_header: */ |
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pBlock = kmalloc(length + sizeof(struct r3964_block_header), |
|
GFP_KERNEL); |
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TRACE_M("on_receive_block - kmalloc %p", pBlock); |
|
|
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if (pBlock == NULL) |
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return; |
|
|
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pBlock->length = length; |
|
pBlock->data = ((unsigned char *)pBlock) + |
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sizeof(struct r3964_block_header); |
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pBlock->locks = 0; |
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pBlock->next = NULL; |
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pBlock->owner = NULL; |
|
|
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memcpy(pBlock->data, pInfo->rx_buf, length); |
|
|
|
/* queue block into rx_queue: */ |
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add_rx_queue(pInfo, pBlock); |
|
|
|
/* notify attached client processes: */ |
|
for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { |
|
if (pClient->sig_flags & R3964_SIG_DATA) { |
|
add_msg(pClient, R3964_MSG_DATA, length, R3964_OK, |
|
pBlock); |
|
} |
|
} |
|
wake_up_interruptible(&pInfo->tty->read_wait); |
|
|
|
pInfo->state = R3964_IDLE; |
|
|
|
trigger_transmit(pInfo); |
|
} |
|
|
|
static void receive_char(struct r3964_info *pInfo, const unsigned char c) |
|
{ |
|
switch (pInfo->state) { |
|
case R3964_TX_REQUEST: |
|
if (c == DLE) { |
|
TRACE_PS("TX_REQUEST - got DLE"); |
|
|
|
pInfo->state = R3964_TRANSMITTING; |
|
pInfo->tx_position = 0; |
|
|
|
transmit_block(pInfo); |
|
} else if (c == STX) { |
|
if (pInfo->nRetry == 0) { |
|
TRACE_PE("TX_REQUEST - init conflict"); |
|
if (pInfo->priority == R3964_SLAVE) { |
|
goto start_receiving; |
|
} |
|
} else { |
|
TRACE_PE("TX_REQUEST - secondary init " |
|
"conflict!? Switching to SLAVE mode " |
|
"for next rx."); |
|
goto start_receiving; |
|
} |
|
} else { |
|
TRACE_PE("TX_REQUEST - char != DLE: %x", c); |
|
retry_transmit(pInfo); |
|
} |
|
break; |
|
case R3964_TRANSMITTING: |
|
if (c == NAK) { |
|
TRACE_PE("TRANSMITTING - got NAK"); |
|
retry_transmit(pInfo); |
|
} else { |
|
TRACE_PE("TRANSMITTING - got invalid char"); |
|
|
|
pInfo->state = R3964_WAIT_ZVZ_BEFORE_TX_RETRY; |
|
mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); |
|
} |
|
break; |
|
case R3964_WAIT_FOR_TX_ACK: |
|
if (c == DLE) { |
|
TRACE_PS("WAIT_FOR_TX_ACK - got DLE"); |
|
remove_from_tx_queue(pInfo, R3964_OK); |
|
|
|
pInfo->state = R3964_IDLE; |
|
trigger_transmit(pInfo); |
|
} else { |
|
retry_transmit(pInfo); |
|
} |
|
break; |
|
case R3964_WAIT_FOR_RX_REPEAT: |
|
case R3964_IDLE: |
|
if (c == STX) { |
|
/* Prevent rx_queue from overflow: */ |
|
if (pInfo->blocks_in_rx_queue >= |
|
R3964_MAX_BLOCKS_IN_RX_QUEUE) { |
|
TRACE_PE("IDLE - got STX but no space in " |
|
"rx_queue!"); |
|
pInfo->state = R3964_WAIT_FOR_RX_BUF; |
|
mod_timer(&pInfo->tmr, |
|
jiffies + R3964_TO_NO_BUF); |
|
break; |
|
} |
|
start_receiving: |
|
/* Ok, start receiving: */ |
|
TRACE_PS("IDLE - got STX"); |
|
pInfo->rx_position = 0; |
|
pInfo->last_rx = 0; |
|
pInfo->flags &= ~R3964_ERROR; |
|
pInfo->state = R3964_RECEIVING; |
|
mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); |
|
pInfo->nRetry = 0; |
|
put_char(pInfo, DLE); |
|
flush(pInfo); |
|
pInfo->bcc = 0; |
|
} |
|
break; |
|
case R3964_RECEIVING: |
|
if (pInfo->rx_position < RX_BUF_SIZE) { |
|
pInfo->bcc ^= c; |
|
|
|
if (c == DLE) { |
|
if (pInfo->last_rx == DLE) { |
|
pInfo->last_rx = 0; |
|
goto char_to_buf; |
|
} |
|
pInfo->last_rx = DLE; |
|
break; |
|
} else if ((c == ETX) && (pInfo->last_rx == DLE)) { |
|
if (pInfo->flags & R3964_BCC) { |
|
pInfo->state = R3964_WAIT_FOR_BCC; |
|
mod_timer(&pInfo->tmr, |
|
jiffies + R3964_TO_ZVZ); |
|
} else { |
|
on_receive_block(pInfo); |
|
} |
|
} else { |
|
pInfo->last_rx = c; |
|
char_to_buf: |
|
pInfo->rx_buf[pInfo->rx_position++] = c; |
|
mod_timer(&pInfo->tmr, jiffies + R3964_TO_ZVZ); |
|
} |
|
} |
|
/* else: overflow-msg? BUF_SIZE>MTU; should not happen? */ |
|
break; |
|
case R3964_WAIT_FOR_BCC: |
|
pInfo->last_rx = c; |
|
on_receive_block(pInfo); |
|
break; |
|
} |
|
} |
|
|
|
static void receive_error(struct r3964_info *pInfo, const char flag) |
|
{ |
|
switch (flag) { |
|
case TTY_NORMAL: |
|
break; |
|
case TTY_BREAK: |
|
TRACE_PE("received break"); |
|
pInfo->flags |= R3964_BREAK; |
|
break; |
|
case TTY_PARITY: |
|
TRACE_PE("parity error"); |
|
pInfo->flags |= R3964_PARITY; |
|
break; |
|
case TTY_FRAME: |
|
TRACE_PE("frame error"); |
|
pInfo->flags |= R3964_FRAME; |
|
break; |
|
case TTY_OVERRUN: |
|
TRACE_PE("frame overrun"); |
|
pInfo->flags |= R3964_OVERRUN; |
|
break; |
|
default: |
|
TRACE_PE("receive_error - unknown flag %d", flag); |
|
pInfo->flags |= R3964_UNKNOWN; |
|
break; |
|
} |
|
} |
|
|
|
static void on_timeout(struct timer_list *t) |
|
{ |
|
struct r3964_info *pInfo = from_timer(pInfo, t, tmr); |
|
|
|
switch (pInfo->state) { |
|
case R3964_TX_REQUEST: |
|
TRACE_PE("TX_REQUEST - timeout"); |
|
retry_transmit(pInfo); |
|
break; |
|
case R3964_WAIT_ZVZ_BEFORE_TX_RETRY: |
|
put_char(pInfo, NAK); |
|
flush(pInfo); |
|
retry_transmit(pInfo); |
|
break; |
|
case R3964_WAIT_FOR_TX_ACK: |
|
TRACE_PE("WAIT_FOR_TX_ACK - timeout"); |
|
retry_transmit(pInfo); |
|
break; |
|
case R3964_WAIT_FOR_RX_BUF: |
|
TRACE_PE("WAIT_FOR_RX_BUF - timeout"); |
|
put_char(pInfo, NAK); |
|
flush(pInfo); |
|
pInfo->state = R3964_IDLE; |
|
break; |
|
case R3964_RECEIVING: |
|
TRACE_PE("RECEIVING - timeout after %d chars", |
|
pInfo->rx_position); |
|
put_char(pInfo, NAK); |
|
flush(pInfo); |
|
pInfo->state = R3964_IDLE; |
|
break; |
|
case R3964_WAIT_FOR_RX_REPEAT: |
|
TRACE_PE("WAIT_FOR_RX_REPEAT - timeout"); |
|
pInfo->state = R3964_IDLE; |
|
break; |
|
case R3964_WAIT_FOR_BCC: |
|
TRACE_PE("WAIT_FOR_BCC - timeout"); |
|
put_char(pInfo, NAK); |
|
flush(pInfo); |
|
pInfo->state = R3964_IDLE; |
|
break; |
|
} |
|
} |
|
|
|
static struct r3964_client_info *findClient(struct r3964_info *pInfo, |
|
struct pid *pid) |
|
{ |
|
struct r3964_client_info *pClient; |
|
|
|
for (pClient = pInfo->firstClient; pClient; pClient = pClient->next) { |
|
if (pClient->pid == pid) { |
|
return pClient; |
|
} |
|
} |
|
return NULL; |
|
} |
|
|
|
static int enable_signals(struct r3964_info *pInfo, struct pid *pid, int arg) |
|
{ |
|
struct r3964_client_info *pClient; |
|
struct r3964_client_info **ppClient; |
|
struct r3964_message *pMsg; |
|
|
|
if ((arg & R3964_SIG_ALL) == 0) { |
|
/* Remove client from client list */ |
|
for (ppClient = &pInfo->firstClient; *ppClient; |
|
ppClient = &(*ppClient)->next) { |
|
pClient = *ppClient; |
|
|
|
if (pClient->pid == pid) { |
|
TRACE_PS("removing client %d from client list", |
|
pid_nr(pid)); |
|
*ppClient = pClient->next; |
|
while (pClient->msg_count) { |
|
pMsg = remove_msg(pInfo, pClient); |
|
if (pMsg) { |
|
kfree(pMsg); |
|
TRACE_M("enable_signals - msg " |
|
"kfree %p", pMsg); |
|
} |
|
} |
|
put_pid(pClient->pid); |
|
kfree(pClient); |
|
TRACE_M("enable_signals - kfree %p", pClient); |
|
return 0; |
|
} |
|
} |
|
return -EINVAL; |
|
} else { |
|
pClient = findClient(pInfo, pid); |
|
if (pClient) { |
|
/* update signal options */ |
|
pClient->sig_flags = arg; |
|
} else { |
|
/* add client to client list */ |
|
pClient = kmalloc(sizeof(struct r3964_client_info), |
|
GFP_KERNEL); |
|
TRACE_M("enable_signals - kmalloc %p", pClient); |
|
if (pClient == NULL) |
|
return -ENOMEM; |
|
|
|
TRACE_PS("add client %d to client list", pid_nr(pid)); |
|
spin_lock_init(&pClient->lock); |
|
pClient->sig_flags = arg; |
|
pClient->pid = get_pid(pid); |
|
pClient->next = pInfo->firstClient; |
|
pClient->first_msg = NULL; |
|
pClient->last_msg = NULL; |
|
pClient->next_block_to_read = NULL; |
|
pClient->msg_count = 0; |
|
pInfo->firstClient = pClient; |
|
} |
|
} |
|
|
|
return 0; |
|
} |
|
|
|
static int read_telegram(struct r3964_info *pInfo, struct pid *pid, |
|
unsigned char __user * buf) |
|
{ |
|
struct r3964_client_info *pClient; |
|
struct r3964_block_header *block; |
|
|
|
if (!buf) { |
|
return -EINVAL; |
|
} |
|
|
|
pClient = findClient(pInfo, pid); |
|
if (pClient == NULL) { |
|
return -EINVAL; |
|
} |
|
|
|
block = pClient->next_block_to_read; |
|
if (!block) { |
|
return 0; |
|
} else { |
|
if (copy_to_user(buf, block->data, block->length)) |
|
return -EFAULT; |
|
|
|
remove_client_block(pInfo, pClient); |
|
return block->length; |
|
} |
|
|
|
return -EINVAL; |
|
} |
|
|
|
static void add_msg(struct r3964_client_info *pClient, int msg_id, int arg, |
|
int error_code, struct r3964_block_header *pBlock) |
|
{ |
|
struct r3964_message *pMsg; |
|
unsigned long flags; |
|
|
|
if (pClient->msg_count < R3964_MAX_MSG_COUNT - 1) { |
|
queue_the_message: |
|
|
|
pMsg = kmalloc(sizeof(struct r3964_message), |
|
error_code ? GFP_ATOMIC : GFP_KERNEL); |
|
TRACE_M("add_msg - kmalloc %p", pMsg); |
|
if (pMsg == NULL) { |
|
return; |
|
} |
|
|
|
spin_lock_irqsave(&pClient->lock, flags); |
|
|
|
pMsg->msg_id = msg_id; |
|
pMsg->arg = arg; |
|
pMsg->error_code = error_code; |
|
pMsg->block = pBlock; |
|
pMsg->next = NULL; |
|
|
|
if (pClient->last_msg == NULL) { |
|
pClient->first_msg = pClient->last_msg = pMsg; |
|
} else { |
|
pClient->last_msg->next = pMsg; |
|
pClient->last_msg = pMsg; |
|
} |
|
|
|
pClient->msg_count++; |
|
|
|
if (pBlock != NULL) { |
|
pBlock->locks++; |
|
} |
|
spin_unlock_irqrestore(&pClient->lock, flags); |
|
} else { |
|
if ((pClient->last_msg->msg_id == R3964_MSG_ACK) |
|
&& (pClient->last_msg->error_code == R3964_OVERFLOW)) { |
|
pClient->last_msg->arg++; |
|
TRACE_PE("add_msg - inc prev OVERFLOW-msg"); |
|
} else { |
|
msg_id = R3964_MSG_ACK; |
|
arg = 0; |
|
error_code = R3964_OVERFLOW; |
|
pBlock = NULL; |
|
TRACE_PE("add_msg - queue OVERFLOW-msg"); |
|
goto queue_the_message; |
|
} |
|
} |
|
/* Send SIGIO signal to client process: */ |
|
if (pClient->sig_flags & R3964_USE_SIGIO) { |
|
kill_pid(pClient->pid, SIGIO, 1); |
|
} |
|
} |
|
|
|
static struct r3964_message *remove_msg(struct r3964_info *pInfo, |
|
struct r3964_client_info *pClient) |
|
{ |
|
struct r3964_message *pMsg = NULL; |
|
unsigned long flags; |
|
|
|
if (pClient->first_msg) { |
|
spin_lock_irqsave(&pClient->lock, flags); |
|
|
|
pMsg = pClient->first_msg; |
|
pClient->first_msg = pMsg->next; |
|
if (pClient->first_msg == NULL) { |
|
pClient->last_msg = NULL; |
|
} |
|
|
|
pClient->msg_count--; |
|
if (pMsg->block) { |
|
remove_client_block(pInfo, pClient); |
|
pClient->next_block_to_read = pMsg->block; |
|
} |
|
spin_unlock_irqrestore(&pClient->lock, flags); |
|
} |
|
return pMsg; |
|
} |
|
|
|
static void remove_client_block(struct r3964_info *pInfo, |
|
struct r3964_client_info *pClient) |
|
{ |
|
struct r3964_block_header *block; |
|
|
|
TRACE_PS("remove_client_block PID %d", pid_nr(pClient->pid)); |
|
|
|
block = pClient->next_block_to_read; |
|
if (block) { |
|
block->locks--; |
|
if (block->locks == 0) { |
|
remove_from_rx_queue(pInfo, block); |
|
} |
|
} |
|
pClient->next_block_to_read = NULL; |
|
} |
|
|
|
/************************************************************* |
|
* Line discipline routines |
|
*************************************************************/ |
|
|
|
static int r3964_open(struct tty_struct *tty) |
|
{ |
|
struct r3964_info *pInfo; |
|
|
|
TRACE_L("open"); |
|
TRACE_L("tty=%p, PID=%d, disc_data=%p", |
|
tty, current->pid, tty->disc_data); |
|
|
|
pInfo = kmalloc(sizeof(struct r3964_info), GFP_KERNEL); |
|
TRACE_M("r3964_open - info kmalloc %p", pInfo); |
|
|
|
if (!pInfo) { |
|
printk(KERN_ERR "r3964: failed to alloc info structure\n"); |
|
return -ENOMEM; |
|
} |
|
|
|
pInfo->rx_buf = kmalloc(RX_BUF_SIZE, GFP_KERNEL); |
|
TRACE_M("r3964_open - rx_buf kmalloc %p", pInfo->rx_buf); |
|
|
|
if (!pInfo->rx_buf) { |
|
printk(KERN_ERR "r3964: failed to alloc receive buffer\n"); |
|
kfree(pInfo); |
|
TRACE_M("r3964_open - info kfree %p", pInfo); |
|
return -ENOMEM; |
|
} |
|
|
|
pInfo->tx_buf = kmalloc(TX_BUF_SIZE, GFP_KERNEL); |
|
TRACE_M("r3964_open - tx_buf kmalloc %p", pInfo->tx_buf); |
|
|
|
if (!pInfo->tx_buf) { |
|
printk(KERN_ERR "r3964: failed to alloc transmit buffer\n"); |
|
kfree(pInfo->rx_buf); |
|
TRACE_M("r3964_open - rx_buf kfree %p", pInfo->rx_buf); |
|
kfree(pInfo); |
|
TRACE_M("r3964_open - info kfree %p", pInfo); |
|
return -ENOMEM; |
|
} |
|
|
|
spin_lock_init(&pInfo->lock); |
|
mutex_init(&pInfo->read_lock); |
|
pInfo->tty = tty; |
|
pInfo->priority = R3964_MASTER; |
|
pInfo->rx_first = pInfo->rx_last = NULL; |
|
pInfo->tx_first = pInfo->tx_last = NULL; |
|
pInfo->rx_position = 0; |
|
pInfo->tx_position = 0; |
|
pInfo->last_rx = 0; |
|
pInfo->blocks_in_rx_queue = 0; |
|
pInfo->firstClient = NULL; |
|
pInfo->state = R3964_IDLE; |
|
pInfo->flags = R3964_DEBUG; |
|
pInfo->nRetry = 0; |
|
|
|
tty->disc_data = pInfo; |
|
tty->receive_room = 65536; |
|
|
|
timer_setup(&pInfo->tmr, on_timeout, 0); |
|
|
|
return 0; |
|
} |
|
|
|
static void r3964_close(struct tty_struct *tty) |
|
{ |
|
struct r3964_info *pInfo = tty->disc_data; |
|
struct r3964_client_info *pClient, *pNext; |
|
struct r3964_message *pMsg; |
|
struct r3964_block_header *pHeader, *pNextHeader; |
|
unsigned long flags; |
|
|
|
TRACE_L("close"); |
|
|
|
/* |
|
* Make sure that our task queue isn't activated. If it |
|
* is, take it out of the linked list. |
|
*/ |
|
del_timer_sync(&pInfo->tmr); |
|
|
|
/* Remove client-structs and message queues: */ |
|
pClient = pInfo->firstClient; |
|
while (pClient) { |
|
pNext = pClient->next; |
|
while (pClient->msg_count) { |
|
pMsg = remove_msg(pInfo, pClient); |
|
if (pMsg) { |
|
kfree(pMsg); |
|
TRACE_M("r3964_close - msg kfree %p", pMsg); |
|
} |
|
} |
|
put_pid(pClient->pid); |
|
kfree(pClient); |
|
TRACE_M("r3964_close - client kfree %p", pClient); |
|
pClient = pNext; |
|
} |
|
/* Remove jobs from tx_queue: */ |
|
spin_lock_irqsave(&pInfo->lock, flags); |
|
pHeader = pInfo->tx_first; |
|
pInfo->tx_first = pInfo->tx_last = NULL; |
|
spin_unlock_irqrestore(&pInfo->lock, flags); |
|
|
|
while (pHeader) { |
|
pNextHeader = pHeader->next; |
|
kfree(pHeader); |
|
pHeader = pNextHeader; |
|
} |
|
|
|
/* Free buffers: */ |
|
kfree(pInfo->rx_buf); |
|
TRACE_M("r3964_close - rx_buf kfree %p", pInfo->rx_buf); |
|
kfree(pInfo->tx_buf); |
|
TRACE_M("r3964_close - tx_buf kfree %p", pInfo->tx_buf); |
|
kfree(pInfo); |
|
TRACE_M("r3964_close - info kfree %p", pInfo); |
|
} |
|
|
|
static ssize_t r3964_read(struct tty_struct *tty, struct file *file, |
|
unsigned char *kbuf, size_t nr, |
|
void **cookie, unsigned long offset) |
|
{ |
|
struct r3964_info *pInfo = tty->disc_data; |
|
struct r3964_client_info *pClient; |
|
struct r3964_message *pMsg; |
|
struct r3964_client_message theMsg; |
|
int ret; |
|
|
|
TRACE_L("read()"); |
|
|
|
/* |
|
* Internal serialization of reads. |
|
*/ |
|
if (file->f_flags & O_NONBLOCK) { |
|
if (!mutex_trylock(&pInfo->read_lock)) |
|
return -EAGAIN; |
|
} else { |
|
if (mutex_lock_interruptible(&pInfo->read_lock)) |
|
return -ERESTARTSYS; |
|
} |
|
|
|
pClient = findClient(pInfo, task_pid(current)); |
|
if (pClient) { |
|
pMsg = remove_msg(pInfo, pClient); |
|
if (pMsg == NULL) { |
|
/* no messages available. */ |
|
if (tty_io_nonblock(tty, file)) { |
|
ret = -EAGAIN; |
|
goto unlock; |
|
} |
|
/* block until there is a message: */ |
|
wait_event_interruptible(tty->read_wait, |
|
(pMsg = remove_msg(pInfo, pClient))); |
|
} |
|
|
|
/* If we still haven't got a message, we must have been signalled */ |
|
|
|
if (!pMsg) { |
|
ret = -EINTR; |
|
goto unlock; |
|
} |
|
|
|
/* deliver msg to client process: */ |
|
theMsg.msg_id = pMsg->msg_id; |
|
theMsg.arg = pMsg->arg; |
|
theMsg.error_code = pMsg->error_code; |
|
ret = sizeof(struct r3964_client_message); |
|
|
|
kfree(pMsg); |
|
TRACE_M("r3964_read - msg kfree %p", pMsg); |
|
|
|
memcpy(kbuf, &theMsg, ret); |
|
|
|
TRACE_PS("read - return %d", ret); |
|
goto unlock; |
|
} |
|
ret = -EPERM; |
|
unlock: |
|
mutex_unlock(&pInfo->read_lock); |
|
return ret; |
|
} |
|
|
|
static ssize_t r3964_write(struct tty_struct *tty, struct file *file, |
|
const unsigned char *data, size_t count) |
|
{ |
|
struct r3964_info *pInfo = tty->disc_data; |
|
struct r3964_block_header *pHeader; |
|
struct r3964_client_info *pClient; |
|
unsigned char *new_data; |
|
|
|
TRACE_L("write request, %d characters", count); |
|
/* |
|
* Verify the pointers |
|
*/ |
|
|
|
if (!pInfo) |
|
return -EIO; |
|
|
|
/* |
|
* Ensure that the caller does not wish to send too much. |
|
*/ |
|
if (count > R3964_MTU) { |
|
if (pInfo->flags & R3964_DEBUG) { |
|
TRACE_L(KERN_WARNING "r3964_write: truncating user " |
|
"packet from %u to mtu %d", count, R3964_MTU); |
|
} |
|
count = R3964_MTU; |
|
} |
|
/* |
|
* Allocate a buffer for the data and copy it from the buffer with header prepended |
|
*/ |
|
new_data = kmalloc(count + sizeof(struct r3964_block_header), |
|
GFP_KERNEL); |
|
TRACE_M("r3964_write - kmalloc %p", new_data); |
|
if (new_data == NULL) { |
|
if (pInfo->flags & R3964_DEBUG) { |
|
printk(KERN_ERR "r3964_write: no memory\n"); |
|
} |
|
return -ENOSPC; |
|
} |
|
|
|
pHeader = (struct r3964_block_header *)new_data; |
|
pHeader->data = new_data + sizeof(struct r3964_block_header); |
|
pHeader->length = count; |
|
pHeader->locks = 0; |
|
pHeader->owner = NULL; |
|
|
|
pClient = findClient(pInfo, task_pid(current)); |
|
if (pClient) { |
|
pHeader->owner = pClient; |
|
} |
|
|
|
memcpy(pHeader->data, data, count); /* We already verified this */ |
|
|
|
if (pInfo->flags & R3964_DEBUG) { |
|
dump_block(pHeader->data, count); |
|
} |
|
|
|
/* |
|
* Add buffer to transmit-queue: |
|
*/ |
|
add_tx_queue(pInfo, pHeader); |
|
trigger_transmit(pInfo); |
|
|
|
return 0; |
|
} |
|
|
|
static int r3964_ioctl(struct tty_struct *tty, struct file *file, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
struct r3964_info *pInfo = tty->disc_data; |
|
if (pInfo == NULL) |
|
return -EINVAL; |
|
switch (cmd) { |
|
case R3964_ENABLE_SIGNALS: |
|
return enable_signals(pInfo, task_pid(current), arg); |
|
case R3964_SETPRIORITY: |
|
if (arg < R3964_MASTER || arg > R3964_SLAVE) |
|
return -EINVAL; |
|
pInfo->priority = arg & 0xff; |
|
return 0; |
|
case R3964_USE_BCC: |
|
if (arg) |
|
pInfo->flags |= R3964_BCC; |
|
else |
|
pInfo->flags &= ~R3964_BCC; |
|
return 0; |
|
case R3964_READ_TELEGRAM: |
|
return read_telegram(pInfo, task_pid(current), |
|
(unsigned char __user *)arg); |
|
default: |
|
return -ENOIOCTLCMD; |
|
} |
|
} |
|
|
|
#ifdef CONFIG_COMPAT |
|
static int r3964_compat_ioctl(struct tty_struct *tty, struct file *file, |
|
unsigned int cmd, unsigned long arg) |
|
{ |
|
switch (cmd) { |
|
case R3964_ENABLE_SIGNALS: |
|
case R3964_SETPRIORITY: |
|
case R3964_USE_BCC: |
|
return r3964_ioctl(tty, file, cmd, arg); |
|
default: |
|
return -ENOIOCTLCMD; |
|
} |
|
} |
|
#endif |
|
|
|
static void r3964_set_termios(struct tty_struct *tty, struct ktermios *old) |
|
{ |
|
TRACE_L("set_termios"); |
|
} |
|
|
|
/* Called without the kernel lock held - fine */ |
|
static __poll_t r3964_poll(struct tty_struct *tty, struct file *file, |
|
struct poll_table_struct *wait) |
|
{ |
|
struct r3964_info *pInfo = tty->disc_data; |
|
struct r3964_client_info *pClient; |
|
struct r3964_message *pMsg = NULL; |
|
unsigned long flags; |
|
__poll_t result = EPOLLOUT; |
|
|
|
TRACE_L("POLL"); |
|
|
|
pClient = findClient(pInfo, task_pid(current)); |
|
if (pClient) { |
|
poll_wait(file, &tty->read_wait, wait); |
|
spin_lock_irqsave(&pInfo->lock, flags); |
|
pMsg = pClient->first_msg; |
|
spin_unlock_irqrestore(&pInfo->lock, flags); |
|
if (pMsg) |
|
result |= EPOLLIN | EPOLLRDNORM; |
|
} else { |
|
result = -EINVAL; |
|
} |
|
return result; |
|
} |
|
|
|
static void r3964_receive_buf(struct tty_struct *tty, const unsigned char *cp, |
|
char *fp, int count) |
|
{ |
|
struct r3964_info *pInfo = tty->disc_data; |
|
const unsigned char *p; |
|
char *f, flags = TTY_NORMAL; |
|
int i; |
|
|
|
for (i = count, p = cp, f = fp; i; i--, p++) { |
|
if (f) |
|
flags = *f++; |
|
if (flags == TTY_NORMAL) { |
|
receive_char(pInfo, *p); |
|
} else { |
|
receive_error(pInfo, flags); |
|
} |
|
|
|
} |
|
} |
|
|
|
MODULE_LICENSE("GPL"); |
|
MODULE_ALIAS_LDISC(N_R3964);
|
|
|