Dummy driver for understanding uio

sys/conf/GENERIC

@@ -261,3 +261,5 @@ FPSIM		NO			# floating point simulator
 PROFILE		NO		# system profiling with KW11P clock
 
 INGRES		NO		# include the Ingres lock driver
+
+NDUMMY		1

sys/conf/Make.pdpuba

@@ -17,9 +17,9 @@ VPATH=	../pdpuba
 CFILES=	${U}/br.c ${U}/dh.c ${U}/dn.c ${U}/dhu.c ${U}/dhv.c ${U}/dkbad.c \
 	${U}/dr.c ${U}/dz.c ${U}/hk.c ${U}/ht.c ${U}/lp.c ${U}/ra.c ${U}/rk.c \
 	${U}/rl.c ${U}/rx.c ${U}/si.c ${U}/tm.c ${U}/tmscp.c ${U}/tmscpdump.c \
-	${U}/ts.c ${U}/xp.c
+	${U}/ts.c ${U}/xp.c ${U}/dummy.c
 OBJS=	br.o dh.o dhu.o dhv.o dkbad.o dn.o dr.o dz.o hk.o ht.o lp.o ra.o rk.o \
-	rl.o rx.o si.o tm.o tmscp.o tmscpdump.o ts.o xp.o dn.o
+	rl.o rx.o si.o tm.o tmscp.o tmscpdump.o ts.o xp.o dn.o dummy.o
 
 .c.o:
 	${CC} ${CFLAGS} -S $*.c

sys/pdp/conf.c

@@ -335,6 +335,16 @@ int	dnopen(), dnclose(), dnwrite();
 #define	dnioctl		nodev
 #endif
 
+#include "dummy.h"
+#if NDUMMY > 0
+int dummyopen(), dummyclose(), dummyread(), dummywrite();
+#else
+#define dummyopen	nodev
+#define dummyclose	nodev
+#define dummyread	nodev
+#define dummywrite	nodev
+#endif
+
 int	logopen(), logclose(), logread(), logioctl(), logselect();
 int	syopen(), syread(), sywrite(), syioctl(), syselect();
 
@@ -467,6 +477,10 @@ struct cdevsw	cdevsw[] = {
 	fdopen,		nodev,		nodev,		nodev,
 	nodev,		nodev,		0,		nodev,
 	nodev,
+/* dummy = 27 */
+	dummyopen,	dummyclose,	dummyread,	dummywrite,
+	nodev,		nulldev,	0, 		nodev,
+	nulldev,
 };
 
 int	nchrdev = sizeof(cdevsw) / sizeof(cdevsw[0]);
@@ -525,7 +539,7 @@ isdisk(dev, type)
 	/* NOTREACHED */
 }
 
-#define MAXDEV	27
+#define MAXDEV	28
 static char chrtoblktbl[MAXDEV] =  {
       /* CHR */      /* BLK */
 	/* 0 */		NODEV,
@@ -554,7 +568,8 @@ static char chrtoblktbl[MAXDEV] =  {
 	/* 23 */	12,		/* tmscp */
 	/* 24 */	NODEV,
 	/* 25 */	NODEV,
-	/* 26 */	NODEV
+	/* 26 */	NODEV,
+	/* 27 */	NODEV,		/* dummy */
 };
 
 /*

sys/pdpuba/dummy.c

@@ -0,0 +1,68 @@
+
+#include "../h/param.h"
+#include "../h/syslog.h"
+#include "../h/uio.h"
+#include "dummy.h"
+
+#define DUMMY_BUFF_LEN 128
+
+dummyattach(addr, unit)
+     struct dummy *addr;
+     u_int unit;
+{
+  log(LOG_INFO, "dummy attach");
+  return 1;
+}
+
+dummyopen(dev, flag)
+     dev_t dev;
+     short flag;
+{
+  log(LOG_INFO, "dummy open");
+  return 0;
+}
+
+dummyclose(dev, flag)
+     dev_t dev;
+     short flag;
+{
+  log(LOG_INFO, "dummy close");
+  return 0;
+}
+
+dummyread(dev, uio, flag)
+     dev_t dev;
+     struct uio *uio;
+     int flag;
+{
+  log(LOG_INFO, "dummy read");
+  ureadc('H', uio);
+  ureadc('e', uio);
+  ureadc('l', uio);
+  ureadc('l', uio);
+  ureadc('o', uio);
+
+  return 0;
+}
+
+dummywrite(dev, uio, flag)
+     dev_t dev;
+     struct uio *uio;
+     int flag;
+{
+  register int n;
+  register char *cp;
+  char inbuf[DUMMY_BUFF_LEN];
+  int error;
+
+  while (n = MIN(DUMMY_BUFF_LEN, uio->uio_resid)) {
+    cp = inbuf;
+    error = uiomove(cp, (int)n, uio);
+    if (error)
+      return error;
+    do
+      log(LOG_NOTICE, "dummy write: c=%c", *cp++);
+    while (--n);
+  }
+  return 0;
+}

sys/pdpuba/dummy.h

@@ -0,0 +1,4 @@
+
+struct dummycsr {
+  long csr;
+};