2005-04-10 Jochen Eisinger <jochen@penguin-breeder.org>

* backend/mustek_pp.c, backend/mustek_pp.conf, sanei/sanei_pa4s2.c,
	  include/sane/sanei_pa4s2.h, doc/sane-mustek_pp.man: added global
	  option "no_epp" to work around a known bug in the linux parport
	  code.

ChangeLog

@@ -1,4 +1,12 @@
+2005-04-10  Jochen Eisinger <jochen@penguin-breeder.org>
+
+	* backend/mustek_pp.c, backend/mustek_pp.conf, sanei/sanei_pa4s2.c,
+	  include/sane/sanei_pa4s2.h, doc/sane-mustek_pp.man: added global
+	  option "no_epp" to work around a known bug in the linux parport
+	  code.
+
 2005-04-02  Julien Blache <jb@jblache.org>
+
 	* doc/sane.man: typo fix from A Costa.
 
 2005-04-01  Gerhard Jaeger <gerhard@gjaeger.de>

backend/mustek_pp.c

@@ -894,13 +894,6 @@ sane_init (SANE_Int * version_code, SANE_Auth_Callback authorize)
           char *optname, *optval = 0;
           Mustek_pp_config_option *tmpoptions;
 
-          if (!name)
-	    {
-	      DBG (1, "sane_init: parse error in line %d: unexpected "
-                      " ``option''\n", line);
-	      continue;
-	    }
-
           config_line_ptr += 6;         
           config_line_ptr = sanei_config_skip_whitespace (config_line_ptr);
           if (!*config_line_ptr)
@@ -942,6 +935,36 @@ sane_init (SANE_Int * version_code, SANE_Auth_Callback authorize)
 	      continue;
 	    }
 
+	  if (!strcmp (optname, "no_epp"))
+	    {
+	      u_int pa4s2_options;
+	      if (name)
+		DBG (2, "sane_init: global option found in local scope, "
+			"executing anyway\n");
+	      free (optname);
+	      if (optval)
+	        {
+	          DBG (1, "sane_init: unexpected value for option no_epp\n");
+	          free (optval);
+	          continue;
+	        }
+	      DBG (3, "sane_init: disabling mode EPP\n");
+	      sanei_pa4s2_options (&pa4s2_options, SANE_FALSE);
+	      pa4s2_options |= SANEI_PA4S2_OPT_NO_EPP;
+	      sanei_pa4s2_options (&pa4s2_options, SANE_TRUE);
+	      continue;
+	    }
+	  else if (!name)
+	    {
+	      DBG (1, "sane_init: parse error in line %d: unexpected "
+                      " ``option''\n", line);
+	      free (optname);
+	      if (optval) 
+                 free (optval);
+	      continue;
+	    }
+
+
           /* Extend the (global) array of options */
           tmpoptions = realloc(cfgoptions, 
                                (numcfgoptions+1)*sizeof(cfgoptions[0]));

backend/mustek_pp.conf

@@ -1,7 +1,20 @@
 # For documentation see sane-mustek_pp(5)
 
+# Global options:
+# ===============
 #
+# option no_epp
+#
+#	    Disable parallel port mode EPP: works around a known bug in
+#	    the Linux parport code. Enable this option, if the backend
+#	    hangs when trying to access the parallel port in EPP mode:
+#
+#	          # SANE_DEBUG_SANEI_PA4S2=128 scanimage -L
+#	          ...
+#  hangs here  -> [sanei_pa4s2] sanei_pa4s2_readbyte: read in EPP mode
+#	 
 # Scanner definition template:
+# ============================
 #
 #  scanner <name> <port> <type>
 #     option <optname> <optval>?

doc/sane-mustek_pp.man

@@ -110,14 +110,19 @@ protocol is still unknown (eg., SE 12000 P).
 .PP
 Some scanners work faster when 
 .B EPP/ECP
-is enabled in the BIOS.
+is enabled in the BIOS. EPP mode however may lead to hard-locks on some Linux
+systems. If that is the case for you, you can either disable ECP/EPP in your
+BIOS or disable it in the backend itself (see GLOBAL OPTIONS).
 .PP
-Note that the backend needs to run as root. To allow user access to the scanner
-run the backend through the network interface (See saned(8) and sane\-net(5)). Note also that the backend
+Note that the backend needs to run as root or has to have appropriate access
+rights to /dev/parport* if libieee1284 support is compiled in. To allow user 
+access to the scanner run the backend through the network interface (See 
+saned(8) and sane\-net(5)). Note also that the backend
 .I does not
 support
 .I parport sharing ,
-i.e. if you try printing while scanning, your computer may crash. This backend
+i.e. if you try printing while scanning, your computer may crash. To enable
+parport sharing, you have to enable libieee1284 at compile time. This backend
 also conflicts with the
 .I sane\-musteka4s2
 backend. You can only enable one of them in your dll.conf. However, you have
@@ -385,6 +390,29 @@ scanner "Mustek 600 III EPP" parport0 ccd300
    option top 56
 .RE
 
+.SH GLOBAL OPTIONS
+.PP
+You can control the overall behaviour of the mustek_pp backend by global
+options which preceed any scanner definition in the mustek_pp.conf file.
+.br
+Currently, there is only one global option:
+
+.TP
+.B Global options
+.RS 4
+.PP
+.HP
+.B no_epp
+Disable parallel port mode EPP: works around a known bug in the Linux parport
+code. Enable this option, if the backend hangs when trying to access the
+parallel port in EPP mode.
+.br
+Default value: use EPP
+.PP
+Example:  option no_epp
+.PP
+.RE
+
 .SH FILES
 .TP
 .I @CONFIGDIR@/mustek_pp.conf

include/sane/sanei_pa4s2.h

@@ -56,6 +56,7 @@
 #define SANEI_PA4S2_OPT_DEFAULT		0	/* normal mode */
 #define SANEI_PA4S2_OPT_TRY_MODE_UNI	1	/* enable UNI protocoll */
 #define SANEI_PA4S2_OPT_ALT_LOCK	2	/* use alternative lock cmd */
+#define SANEI_PA4S2_OPT_NO_EPP		4	/* do not try to use EPP */
 /* @} */
 
 /** Get list of possibly available devices

sanei/sanei_pa4s2.c

@@ -1253,6 +1253,14 @@ sanei_pa4s2_open (const char *dev, int *fd)
 
 	}
 
+      if ((port[*fd].mode == PA4S2_MODE_EPP) &&
+      ((sanei_pa4s2_interface_options & SANEI_PA4S2_OPT_NO_EPP) == 1))
+	{
+	  DBG (3, "sanei_pa4s2_open: skipping mode EPP\n");
+	  break;
+	}
+
+
       DBG (5, "sanei_pa4s2_open: trying mode %u\n", port[*fd].mode);
 
       sanei_pa4s2_enable (*fd, SANE_TRUE);
@@ -1867,7 +1875,7 @@ sanei_pa4s2_options (u_int * options, int set)
   if ((set != SANE_TRUE) && (set != SANE_FALSE))
     DBG (2, "sanei_pa4s2_options: value of set is invalid\n");
 
-  if ((set == SANE_TRUE) && (*options > 3))
+  if ((set == SANE_TRUE) && (*options > 7))
     DBG (2, "sanei_pa4s2_options: value of *options is invalid\n");
 
   if (set == SANE_TRUE)