Major ppbus updates from the author.

 - ppbus now supports PLIP via the if_plip driver
 - ieee1284 infrastructure added, including parallel-port PnP
 - port microsequencer added, for scripting the sort of port I/O
   that is common with parallel devices without endless calls up and down
   through the driver structure.
 - improved bus ownership behaviour among the ppbus-using drivers.
 - improved I/O chipset feature detection

The vpo driver is now implemented using the microsequencer, leading to
some performance improvements as well as providing an extensive example
of its use.

Reviewed by:	msmith
Submitted by:	Nicolas Souchu <Nicolas.Souchu@prism.uvsq.fr>

1 files changed, 54 insertions, 18 deletions

diff --git a/sys/dev/ppbus/ppb_1284.c b/sys/dev/ppbus/ppb_1284.c
index d1ab1c5..0a0ddeb 100644
--- a/sys/dev/ppbus/ppb_1284.c
+++ b/sys/dev/ppbus/ppb_1284.c
@@ -23,7 +23,7 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
- *	$Id: ppb_1284.c,v 1.2 1997/09/01 00:51:44 bde Exp $
+ *	$Id: ppb_1284.c,v 1.3 1998/01/31 07:23:06 eivind Exp $
  *
  */
 
@@ -38,14 +38,23 @@
 #include <dev/ppbus/ppb_1284.h>
 
 /*
- * nibble_1284_wait()
+ * do_1284_wait()
  *
  * Wait for the peripherial up to 40ms
  */
 int
-nibble_1284_wait(struct ppb_device *dev, char mask, char status)
+do_1284_wait(struct ppb_device *dev, char mask, char status)
 {
 	int i;
+	char r;
+
+	/* try up to 5ms */
+	for (i = 0; i < 20; i++) {
+		r = ppb_rstr(dev);
+		DELAY(25);
+		if ((r & mask) == status)
+			return (0);
+	}
 
 	return (ppb_poll_device(dev, 4, mask, status, PPB_NOINTR));
 }
@@ -53,26 +62,55 @@ nibble_1284_wait(struct ppb_device *dev, char mask, char status)
 #define nibble2char(s) (((s & ~nACK) >> 3) | (~s & nBUSY) >> 4)
 
 /*
+ * byte_1284_inbyte()
+ *
+ * Read 1 byte in BYTE mode
+ */
+int
+byte_1284_inbyte(struct ppb_device *dev, char *buffer)
+{
+	int error;
+
+	/* notify the peripherial to put data on the lines */
+	ppb_wctr(dev, PCD |  AUTOFEED | nSTROBE | nINIT | nSELECTIN);
+
+	/* wait for valid byte signal */
+	if ((error = do_1284_wait(dev, nACK, 0)))
+		return (error);
+
+	/* fetch data */
+	*buffer = ppb_rdtr(dev);
+
+	/* indicate that data has been received, not ready for another */
+	ppb_wctr(dev, PCD | nAUTOFEED | nSTROBE | nINIT | nSELECTIN);
+
+	/* wait peripherial's acknowledgement */
+	if ((error = do_1284_wait(dev, nACK, nACK)))
+		return (error);
+
+	/* acknowledge the peripherial */
+	ppb_wctr(dev, PCD | nAUTOFEED |  STROBE | nINIT | nSELECTIN);
+
+	return (0);
+}
+
+/*
  * nibble_1284_inbyte()
  *
- * Read data in NIBBLE mode
+ * Read 1 byte in NIBBLE mode
  */
 int
 nibble_1284_inbyte(struct ppb_device *dev, char *buffer)
 {
-	char nibble[2], r;
+	char nibble[2];
 	int i, error;
 
-	r = ppb_rctr(dev);
-
 	for (i = 0; i < 2; i++) {
 		/* ready to take data (nAUTO low) */
-		ppb_wctr(dev, r | AUTOFEED);
+		ppb_wctr(dev, AUTOFEED | nSTROBE | nINIT | nSELECTIN);
 
-		if ((error = nibble_1284_wait(dev, nACK, 0))) {
-			ppb_wctr(dev, r);
+		if ((error = do_1284_wait(dev, nACK, 0)))
 			return (error);
-		}
 
 		/* read nibble */
 		nibble[i] = ppb_rstr(dev);
@@ -82,13 +120,11 @@ nibble_1284_inbyte(struct ppb_device *dev, char *buffer)
 #endif
 
 		/* ack, not ready for another nibble */
-		ppb_wctr(dev, r & ~AUTOFEED);
+		ppb_wctr(dev, nAUTOFEED | nSTROBE | nINIT | nSELECTIN);
 
 		/* wait ack from peripherial */
-		if ((error = nibble_1284_wait(dev, nACK, nACK))) {
-			ppb_wctr(dev, r);
+		if ((error = do_1284_wait(dev, nACK, nACK)))
 			return (error);
-		}
 	}
 
 	*buffer = ((nibble2char(nibble[1]) << 4) & 0xf0) |
@@ -112,11 +148,11 @@ nibble_1284_sync(struct ppb_device *dev)
 	ctr = ppb_rctr(dev);
 
 	ppb_wctr(dev, (ctr & ~AUTOFEED) | SELECTIN);
-	if (nibble_1284_wait(dev, nACK, 0))
+	if (do_1284_wait(dev, nACK, 0))
 		return;
 
 	ppb_wctr(dev, ctr | AUTOFEED);
-	nibble_1284_wait(dev, nACK, nACK);
+	do_1284_wait(dev, nACK, nACK);
 
 	ppb_wctr(dev, (ctr & ~AUTOFEED) | SELECTIN);
 
@@ -140,7 +176,7 @@ nibble_1284_mode(struct ppb_device *dev, int mode)
 	DELAY(5);
 
 	ppb_wctr(dev, (ctrl & ~SELECTIN) | AUTOFEED);
-	if ((error = nibble_1284_wait(dev, nACK | ERROR | SELECT | nFAULT,
+	if ((error = do_1284_wait(dev, nACK | ERROR | SELECT | nFAULT,
 			ERROR | SELECT | nFAULT))) {
 		ppb_wctr(dev, ctrl);
 		return (error);