[lcd4linux @ 2003-04-04 06:01:59 by reinelt]

new parallel port abstraction scheme

1 files changed, 346 insertions, 0 deletions

diff --git a/parport.c b/parport.c
new file mode 100644
index 0000000..6e7cbe4
--- /dev/null
+++ b/parport.c
@@ -0,0 +1,346 @@
+/* $Id: parport.c,v 1.1 2003/04/04 06:02:03 reinelt Exp $
+ *
+ * generic parallel port handling
+ *
+ * Copyright 2003 by Michael Reinelt (reinelt@eunet.at)
+ *
+ * This program 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.
+ *
+ * This program 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: parport.c,v $
+ * Revision 1.1  2003/04/04 06:02:03  reinelt
+ * new parallel port abstraction scheme
+ *
+ */
+
+/* 
+ * exported functions:
+ * 
+ * int parport_open (void)
+ *   reads 'Port' entry from config and opens
+ *   the parallel port
+ *   returns 0 if ok, -1 on failure
+ *
+ * int parport_close (void)
+ *   closes parallel port
+ *   returns 0 if ok, -1 on failure
+ *
+ * unsigned char parport_wire (char *name, char *deflt)
+ *   reads wiring for one control signal from config
+ *   returns PARPORT_CONTROL_* or 255 on error
+ *
+ * void parport_control (unsigned char mask, unsigned char value)
+ *   frobs control line and takes care of inverted signals
+ *
+ * void parport_toggle (unsigned char bit, int level, int delay)
+ *   toggles the line <bit> to <level> for <delay> nanoseconds
+ *
+ * void parport_data (unsigned char value)
+ *   put data bits on DB1..DB8
+ *
+ */
+
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <time.h>
+#include <errno.h>
+#include <sys/ioctl.h>
+
+
+#ifdef HAVE_SYS_IO_H
+#include <sys/io.h>
+#define WITH_OUTB
+#else
+#ifdef HAVE_ASM_IO_H
+#include <asm/io.h>
+#define WITH_OUTB
+#endif
+#endif
+
+#if defined (HAVE_LINUX_PARPORT_H) && defined (HAVE_LINUX_PPDEV_H)
+#define WITH_PPDEV
+#include <linux/parport.h>
+#include <linux/ppdev.h>
+#else
+#define PARPORT_CONTROL_STROBE    0x1
+#define PARPORT_CONTROL_AUTOFD    0x2
+#define PARPORT_CONTROL_INIT      0x4
+#define PARPORT_CONTROL_SELECT    0x8
+#endif
+
+#if !defined(WITH_OUTB) && !defined(WITH_PPDEV)
+#error neither outb() nor ppdev() possible
+#error cannot compile parallel port driver
+#endif
+
+
+#include "debug.h"
+#include "cfg.h"
+#include "udelay.h"
+#include "parport.h"
+
+
+static unsigned short Port=0;
+static char *PPdev=NULL;
+
+// initial value taken from linux/parport_pc.c
+static unsigned char ctr = 0xc;
+
+#ifdef WITH_PPDEV
+static int PPfd=-1;
+#endif
+
+int parport_open (void)
+{
+  char *s, *e;
+
+#ifdef USE_OLD_UDELAY
+  s=cfg_get ("Delay",NULL);
+  if (s==NULL || *s=='\0') {
+    error ("parport: no 'Delay' entry in %s", cfg_file());
+    return -1;
+  }
+  if ((loops_per_usec=strtol(s, &e, 0))==0 || *e!='\0') {
+    error ("parport: bad delay '%s' in %s", s, cfg_file());
+    return -1;
+  }    
+#else
+  udelay_init();
+#endif
+  
+  s=cfg_get ("Port",NULL);
+  if (s==NULL || *s=='\0') {
+    error ("parport: no 'Port' entry in %s", cfg_file());
+    return -1;
+  }
+  PPdev=NULL;
+  if ((Port=strtol(s, &e, 0))==0 || *e!='\0') {
+#ifdef WITH_PPDEV
+    Port=0;
+    PPdev=s;
+#else
+    error ("parport: bad Port '%s' in %s", s, cfg_file());
+    return -1;
+#endif
+  }
+  
+  
+#ifdef WITH_PPDEV
+  
+  if (PPdev) {
+    debug ("using ppdev %s", PPdev);
+    PPfd=open(PPdev, O_RDWR);
+    if (PPfd==-1) {
+      error ("parport: open(%s) failed: %s", PPdev, strerror(errno));
+      return -1;
+    }
+    
+#if 0
+    // Fixme
+    if (ioctl(PPfd, PPEXCL)) {
+      debug ("ioctl(%s, PPEXCL) failed: %s", PPdev, strerror(errno));
+    } else {
+      debug ("ioctl(%s, PPEXCL) succeded.");
+    }
+#endif
+    
+    if (ioctl(PPfd, PPCLAIM)) {
+      error ("parport: ioctl(%s, PPCLAIM) failed: %d %s", PPdev, errno, strerror(errno));
+      return -1;
+    }
+  } else
+    
+#endif
+    
+    {
+      debug ("using raw port 0x%x", Port);
+      if (ioperm(Port, 3, 1)!=0) {
+	error ("parport: ioperm(0x%x) failed: %s", Port, strerror(errno));
+	return -1;
+      }
+    }
+  return 0;
+}
+
+
+int parport_close (void)
+{
+#ifdef WITH_PPDEV
+  if (PPdev) {
+    debug ("closing ppdev %s", PPdev);
+    if (ioctl(PPfd, PPRELEASE)) {
+      error ("parport: ioctl(%s, PPRELEASE) failed: %s", PPdev, strerror(errno));
+    }
+    if (close(PPfd)==-1) {
+      error ("parport: close(%s) failed: %s", PPdev, strerror(errno));
+      return -1;
+    }
+  } else 
+#endif    
+    {
+      debug ("closing raw port 0x%x", Port);
+      if (ioperm(Port, 3, 0)!=0) {
+	error ("parport: ioperm(0x%x) failed: %s", Port, strerror(errno));
+	return -1;
+      }
+    }
+  return 0;
+}
+
+
+unsigned char parport_wire (char *name, unsigned char *deflt)
+{
+  unsigned char w;
+  char wire[256];
+  char *s;
+  int n;
+  
+  snprintf (wire, sizeof(wire), "Wire.%s", name);
+  s=cfg_get (wire,deflt);
+  if (strcasecmp(s,"STROBE")==0) {
+    w=PARPORT_CONTROL_STROBE;
+  } else if(strcasecmp(s,"AUTOFD")==0) {
+    w=PARPORT_CONTROL_AUTOFD;
+  } else if(strcasecmp(s,"INIT")==0) {
+    w=PARPORT_CONTROL_INIT;
+  } else if(strcasecmp(s,"SELECT")==0) {
+    w=PARPORT_CONTROL_SELECT;
+  } else {
+    error ("parport: unknown signal <%s> for wire <%s>", s, name);
+    error ("         should be STROBE, AUTOFD, INIT or SELECT");
+    return 255;
+  }
+  
+  n=0;
+  if (w&PARPORT_CONTROL_STROBE) {
+    n++;
+    info ("wiring: [DISPLAY:%s]==[PARPORT:STROBE]", name);
+  }
+  if (w&PARPORT_CONTROL_AUTOFD) {
+    n++;
+    info ("wiring: [DISPLAY:%s]==[PARPORT:AUTOFD]", name);
+  }
+  if (w&PARPORT_CONTROL_INIT) {
+    n++;
+    info ("wiring: [DISPLAY:%s]==[PARPORT:INIT]", name);
+  }
+  if (w&PARPORT_CONTROL_SELECT) {
+    n++;
+    info ("wiring: [DISPLAY:%s]==[PARPORT:SELECT]", name);
+  }
+  if (n<1) {
+    error ("parport: no signal for wire <%s> found!", name);
+    return 255;
+  }
+  if (n>1) {
+    error ("parport: more than one signal for wire <%s> found!", name);
+    return 255;
+  }
+  return w;
+}
+
+
+void parport_control (unsigned char mask, unsigned char value)
+{
+
+  // sanity check
+  if (mask==0) {
+    error ("parport: internal error: control without signal called!");
+    return;
+  }
+
+  // Strobe, Select and AutoFeed are inverted!
+  value ^= PARPORT_CONTROL_STROBE|PARPORT_CONTROL_SELECT|PARPORT_CONTROL_AUTOFD;
+
+#ifdef WITH_PPDEV
+  if (PPdev) {
+    struct ppdev_frob_struct frob;
+    frob.mask=mask;
+    frob.val=value;
+    ioctl (PPfd, PPFCONTROL, &frob);
+  } else
+#endif
+    {
+      // code stolen from linux/parport_pc.h
+      ctr = (ctr & ~mask) ^ value;
+      outb (ctr, Port+2);
+    }
+}
+
+
+void parport_toggle (unsigned char bit, int level, int delay)
+{
+
+  // sanity check
+  if (bit==0) {
+    error ("parport: internal error: toggle without signal called!");
+    return;
+  }
+
+   // Strobe, Select and AutoFeed are inverted!
+  if (bit & (PARPORT_CONTROL_STROBE|PARPORT_CONTROL_SELECT|PARPORT_CONTROL_AUTOFD)) {
+    level=!level;
+  }
+ 
+#ifdef WITH_PPDEV
+  if (PPdev) {
+    struct ppdev_frob_struct frob;
+    frob.mask=bit;
+    
+    // rise
+    frob.val=level?bit:0;
+    ioctl (PPfd, PPFCONTROL, &frob);
+    
+    // pulse width
+    ndelay(delay);      
+    
+    // lower
+    frob.val=level?0:bit;
+    ioctl (PPfd, PPFCONTROL, &frob);
+  } else
+#endif
+    {
+      // rise
+      ctr = (ctr & ~bit) ^ (level?bit:0);
+      outb (ctr, Port+2);
+
+      // pulse width
+      ndelay(delay);      
+      
+      // lower
+      ctr = (ctr & ~bit) ^ (level?0:bit);
+      outb (ctr, Port+2);
+    }
+}
+
+
+void parport_data (unsigned char data)
+{
+#ifdef WITH_PPDEV
+  if (PPdev) {
+    ioctl(PPfd, PPWDATA, &data);
+  } else
+#endif
+    {
+      outb (data, Port);
+    }
+}
+