/* $Id: drv_generic_serial.c,v 1.6 2004/02/14 11:56:17 reinelt Exp $
*
* generic driver helper for serial and usbserial displays
*
* Copyright 1999, 2000 Michael Reinelt <reinelt@eunet.at>
* Copyright 2004 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
*
* This file is part of LCD4Linux.
*
* LCD4Linux is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* LCD4Linux is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*
*
* $Log: drv_generic_serial.c,v $
* Revision 1.6 2004/02/14 11:56:17 reinelt
* M50530 driver ported
* changed lots of 'char' to 'unsigned char'
*
* Revision 1.5 2004/02/04 19:10:51 reinelt
* Crystalfontz driver nearly finished
*
* Revision 1.4 2004/02/01 08:05:12 reinelt
* Crystalfontz 633 extensions (CRC checking and stuff)
* Models table for HD44780
* Noritake VFD BVrightness patch from Bill Paxton
*
* Revision 1.3 2004/01/29 04:40:02 reinelt
* every .c file includes "config.h" now
*
* Revision 1.2 2004/01/25 05:30:09 reinelt
* plugin_netdev for parsing /proc/net/dev added
*
* Revision 1.1 2004/01/20 14:26:09 reinelt
* moved drv_generic to drv_generic_serial
*
* Revision 1.2 2004/01/20 05:36:59 reinelt
* moved text-display-specific stuff to drv_generic_text
* moved all the bar stuff from drv_generic_bar to generic_text
*
* Revision 1.1 2004/01/20 04:51:39 reinelt
* moved generic stuff from drv_MatrixOrbital to drv_generic
* implemented new-stylish bars which are nearly finished
*
*/
/*
*
* exported fuctions:
*
* int drv_generic_serial_open (char *driver, char *port, speed_t speed);
* opens the serial port
*
* int drv_generic_serial_poll (unsigned char *string, int len)
* reads from the serial or USB port
* without retry
*
* int drv_generic_serial_read (unsigned char *string, int len);
* reads from the serial or USB port
* with retry
*
* void drv_generic_serial_write (unsigned char *string, int len);
* writes to the serial or USB port
*
* int drv_generic_serial_close (void);
* closes the serial port
*
*/
#include "config.h"
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <termios.h>
#include <fcntl.h>
#include <time.h>
#include <signal.h>
#include <sys/types.h>
#include <sys/stat.h>
#include "debug.h"
#include "cfg.h"
#include "drv_generic_serial.h"
static char *Driver;
static char *Port;
static speed_t Speed;
static int Device=-1;
#define LOCK "/var/lock/LCK..%s"
// ****************************************
// *** generic serial/USB communication ***
// ****************************************
pid_t drv_generic_serial_lock_port (char *Port)
{
char lockfile[256];
char tempfile[256];
char buffer[16];
char *port, *p;
int fd, len, pid;
if (strncmp(Port, "/dev/", 5)==0) {
port=strdup(Port+5);
} else {
port=strdup(Port);
}
while ((p=strchr(port, '/'))!=NULL) {
*p='_';
}
snprintf(lockfile, sizeof(lockfile), LOCK, port);
snprintf(tempfile, sizeof(tempfile), LOCK, "TMP.XXXXXX");
free (port);
if ((fd=mkstemp(tempfile))==-1) {
error ("mkstemp(%s) failed: %s", tempfile, strerror(errno));
return -1;
}
if (fchmod(fd,S_IRUSR|S_IWUSR|S_IRGRP|S_IROTH)==-1) {
error ("fchmod(%s) failed: %s", tempfile, strerror(errno));
close(fd);
unlink(tempfile);
return -1;
}
snprintf (buffer, sizeof(buffer), "%10d\n", (int)getpid());
if (write(fd, buffer, strlen(buffer))!=strlen(buffer)) {
error ("write(%s) failed: %s", tempfile, strerror(errno));
close(fd);
unlink(tempfile);
return -1;
}
close (fd);
while (link(tempfile, lockfile)==-1) {
if (errno!=EEXIST) {
error ("link(%s, %s) failed: %s", tempfile, lockfile, strerror(errno));
unlink(tempfile);
return -1;
}
if ((fd=open(lockfile, O_RDONLY))==-1) {
if (errno==ENOENT) continue; // lockfile disappared
error ("open(%s) failed: %s", lockfile, strerror(errno));
unlink (tempfile);
return -1;
}
len=read(fd, buffer, sizeof(buffer)-1);
if (len<0) {
error ("read(%s) failed: %s", lockfile, strerror(errno));
unlink (tempfile);
return -1;
}
buffer[len]='\0';
if (sscanf(buffer, "%d", &pid)!=1 || pid==0) {
error ("scan(%s) failed.", lockfile);
unlink (tempfile);
return -1;
}
if (pid==getpid()) {
error ("%s already locked by us. uh-oh...", lockfile);
unlink(tempfile);
return 0;
}
if ((kill(pid, 0)==-1) && errno==ESRCH) {
error ("removing stale lockfile %s", lockfile);
if (unlink(lockfile)==-1 && errno!=ENOENT) {
error ("unlink(%s) failed: %s", lockfile, strerror(errno));
unlink(tempfile);
return pid;
}
continue;
}
unlink (tempfile);
return pid;
}
unlink (tempfile);
return 0;
}
static pid_t drv_generic_serial_unlock_port (char *Port)
{
char lockfile[256];
char *port, *p;
if (strncmp(Port, "/dev/", 5)==0) {
port=strdup(Port+5);
} else {
port=strdup(Port);
}
while ((p=strchr(port, '/'))!=NULL) {
*p='_';
}
snprintf(lockfile, sizeof(lockfile), LOCK, port);
unlink (lockfile);
free (port);
return 0;
}
int drv_generic_serial_open (char *section, char *driver)
{
int i, fd;
pid_t pid;
struct termios portset;
Driver = driver;
Port=cfg_get(section, "Port", NULL);
if (Port==NULL || *Port=='\0') {
error ("%s: no '%s.Port' entry from %s", Driver, section, cfg_source());
return -1;
}
if (cfg_number(section, "Speed", 19200, 1200, 115200, &i)<0) return -1;
switch (i) {
case 1200: Speed = B1200; break;
case 2400: Speed = B2400; break;
case 4800: Speed = B4800; break;
case 9600: Speed = B9600; break;
case 19200: Speed = B19200; break;
case 38400: Speed = B38400; break;
case 57600: Speed = B57600; break;
case 115200: Speed = B115200; break;
default:
error ("%s: unsupported speed '%d' from %s", Driver, i, cfg_source());
return -1;
}
info ("%s: using port '%s' at %d baud", Driver, Port, i);
if ((pid=drv_generic_serial_lock_port(Port))!=0) {
if (pid==-1)
error ("%s: port %s could not be locked", Driver, Port);
else
error ("%s: port %s is locked by process %d", Driver, Port, pid);
return -1;
}
fd = open(Port, O_RDWR | O_NOCTTY | O_NDELAY);
if (fd==-1) {
error ("%s: open(%s) failed: %s", Driver, Port, strerror(errno));
drv_generic_serial_unlock_port(Port);
return -1;
}
if (tcgetattr(fd, &portset)==-1) {
error ("%s: tcgetattr(%s) failed: %s", Driver, Port, strerror(errno));
drv_generic_serial_unlock_port(Port);
return -1;
}
cfmakeraw(&portset);
cfsetospeed(&portset, Speed);
if (tcsetattr(fd, TCSANOW, &portset)==-1) {
error ("%s: tcsetattr(%s) failed: %s", Driver, Port, strerror(errno));
drv_generic_serial_unlock_port(Port);
return -1;
}
Device=fd;
return Device;
}
int drv_generic_serial_poll (unsigned char *string, int len)
{
int ret;
if (Device==-1) return -1;
ret=read (Device, string, len);
if (ret<0 && errno!=EAGAIN) {
error("%s: read(%s) failed: %s", Driver, Port, strerror(errno));
}
return ret;
}
int drv_generic_serial_read (unsigned char *string, int len)
{
int run, ret;
for (run=0; run<10; run++) {
ret=drv_generic_serial_poll(string, len);
if (ret>=0 || errno!=EAGAIN) break;
info ("%s: read(%s): EAGAIN", Driver, Port);
usleep(1000);
}
if (ret>0 && ret!=len) {
error ("%s: partial read(%s): len=%d ret=%d", Driver, Port, len, ret);
}
return ret;
}
void drv_generic_serial_write (unsigned char *string, int len)
{
int run, ret;
if (Device==-1) return;
for (run=0; run<10; run++) {
ret=write (Device, string, len);
if (ret>=0 || errno!=EAGAIN) break;
info ("%s: write(%s): EAGAIN", Driver, Port);
usleep(1000);
}
if (ret<0) {
error ("%s: write(%s) failed: %s", Driver, Port, strerror(errno));
} else if (ret!=len) {
error ("%s: partial write(%s): len=%d ret=%d", Driver, Port, len, ret);
}
return;
}
int drv_generic_serial_close (void)
{
info ("%s: closing port %s", Driver, Port);
close (Device);
drv_generic_serial_unlock_port(Port);
return 0;
}