--- linux/drivers/char/lp.c	Fri Oct 21 08:58:37 1994
+++ linux/drivers/char/lp.c	Fri Oct 21 09:20:36 1994
@@ -5,6 +5,8 @@
  *   checking ought to be.
  * Copyright (C) 1993 by Nigel Gamble (added interrupt code)
  * Copyright (C) 1994 by Alan Cox (Modularised it)
+ * Copyright (C) 1994 by Yan Zhou, off-line printer support
+ * Copyright (C) 1994 by Karl Keyte, modified off-line printer code
  */
 
 #include <linux/errno.h>
@@ -13,6 +15,9 @@
 #include <linux/sched.h>
 #include <linux/lp.h>
 #include <linux/malloc.h>
+#ifdef CONFIG_OFFLINE_LP
+#include <linux/fcntl.h>
+#endif
 
 #include <asm/io.h>
 #include <asm/segment.h>
@@ -43,6 +48,13 @@
 
 #undef LP_DEBUG
 
+#ifdef CONFIG_OFFLINE_LP
+#define LP_SERROR(x) (!((x) & LP_PERRORP))            /* Error */
+#define LP_SBUSY(x) (!((x) & LP_PBUSY))                       /* Busy */
+#define LP_SOFFLINE(x) (!((x) & LP_PSELECD))          /* Off-line */
+#define LP_SREADY(x)  (!LP_SERROR((x)) && !LP_SOFFLINE((x)) && !LP_SBUSY((x)))
+#endif
+
 static int lp_reset(int minor)
 {
 	int testvalue;
@@ -72,7 +84,12 @@
 		count ++;
 		if(need_resched)
 			schedule();
+
+#ifdef CONFIG_OFFLINE_LP
+	} while(!LP_SREADY(status) && count < LP_CHAR(minor));
+#else
 	} while(!(status & LP_PBUSY) && count < LP_CHAR(minor));
+#endif
 
 	if (count == LP_CHAR(minor)) {
 		return 0;
@@ -102,11 +119,16 @@
 	int wait = 0;
 	unsigned char status;
 
-
+#ifdef CONFIG_OFFLINE_LP
+	status = LP_S(minor);
+	if (!LP_SREADY(status)) status = LP_S(minor);
+	if (!LP_SREADY(status)) status = LP_S(minor);
+	if ( LP_SREADY(status)) {
+#else
 	if (!((status = LP_S(minor)) & LP_PACK) || (status & LP_PBUSY)
 	|| !((status = LP_S(minor)) & LP_PACK) || (status & LP_PBUSY)
 	|| !((status = LP_S(minor)) & LP_PACK) || (status & LP_PBUSY)) {
-
+#endif
 		outb_p(lpchar, LP_B(minor));
 		/* must wait before taking strobe high, and after taking strobe
 		   low, according spec.  Some printers need it, others don't. */
@@ -159,7 +181,12 @@
 				--copy_size;
 				++bytes_written;
 			} else {
+#ifdef CONFIG_OFFLINE_LP
+				status = LP_S(minor);
+				if (LP_SERROR(status)) {
+#else
 				if (!((status = LP_S(minor)) & LP_PERRORP)) {
+#endif
 					int rc = total_bytes_written + bytes_written;
 
 					if ((status & LP_POUTPA)) {
@@ -177,11 +204,19 @@
 					}
 					if(LP_F(minor) & LP_ABORT)
 						return rc;
+#ifdef CONFIG_OFFLINE_LP
+					if (LP_SOFFLINE(status))
+						return rc;
+#endif
 				}
 				cli();
 				outb_p((LP_PSELECP|LP_PINITP|LP_PINTEN), (LP_C(minor)));
 				status = LP_S(minor);
+#ifdef CONFIG_OFFLINE_LP
+				if (LP_SREADY(status)) {
+#else
 				if (!(status & LP_PACK) || (status & LP_PBUSY)) {
+#endif
 					outb_p((LP_PSELECP|LP_PINITP), (LP_C(minor)));
 					sti();
 					continue;
@@ -308,6 +343,10 @@
 		return -ENODEV;
 	if (LP_F(minor) & LP_BUSY)
 		return -EBUSY;
+#ifdef CONFIG_OFFLINE_LP
+	if (LP_SOFFLINE(LP_S(minor)) && !(file->f_flags & O_NDELAY))
+		return -EIO;
+#endif
 
 	if ((irq = LP_IRQ(minor))) {
 		lp_table[minor].lp_buffer = (char *) kmalloc(LP_BUFFER_SIZE, GFP_KERNEL);
@@ -466,9 +505,13 @@
 			lp_reset(offset);
 			printk("lp_init: lp%d exists, ", offset);
 			if (LP_IRQ(offset))
-				printk("using IRQ%d\n", LP_IRQ(offset));
+				printk("using IRQ%d", LP_IRQ(offset));
 			else
-				printk("using polling driver\n");
+				printk("using polling driver");
+#ifdef CONFIG_OFFLINE_LP
+			printk(" (off-line support)");
+#endif
+			printk("\n");
 			count++;
 		}
 	}
@@ -503,9 +546,13 @@
 			lp_reset(offset);
 			printk("lp_init: lp%d exists, ", offset);
 			if (LP_IRQ(offset))
-				printk("using IRQ%d\n", LP_IRQ(offset));
+				printk("using IRQ%d", LP_IRQ(offset));
 			else
-				printk("using polling driver\n");
+				printk("using polling driver");
+#ifdef CONFIG_OFFLINE_LP
+			printk(" (off-line support)");
+#endif
+			printk("\n");
 			count++;
 		}
 	}
--- linux/arch/i386/config.in	Fri Oct 21 09:23:16 1994
+++ linux/arch/i386/config.in	Fri Oct 21 09:22:52 1994
@@ -166,6 +166,9 @@
 comment 'character devices'
 
 bool 'Parallel printer support' CONFIG_PRINTER n
+if [ "$CONFIG_PRINTER" = "y" ]; then
+bool ' Off-line printer support' CONFIG_OFFLINE_LP y
+fi
 bool 'Logitech busmouse support' CONFIG_BUSMOUSE n
 bool 'PS/2 mouse (aka "auxiliary device") support' CONFIG_PSMOUSE n
 if [ "$CONFIG_PSMOUSE" = "y" ]; then