From 2a14fd50d9972f6d71495a96b25adaaa66d47774 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?S=C3=B8ren=20Schmidt?= <sos@FreeBSD.org>
Date: Sat, 18 Mar 2000 22:42:45 +0000
Subject: [PATCH] Remove the old DSC code, it doesn't work anymore.

---
 sys/dev/ata/ata-all.c    | 35 +----------------------------------
 sys/dev/ata/atapi-all.c  |  7 -------
 sys/dev/ata/atapi-all.h  |  3 +--
 sys/dev/ata/atapi-tape.c | 12 +++---------
 4 files changed, 5 insertions(+), 52 deletions(-)

diff --git a/sys/dev/ata/ata-all.c b/sys/dev/ata/ata-all.c
index 63ace7c6a8c0..fe87b766abf4 100644
--- a/sys/dev/ata/ata-all.c
+++ b/sys/dev/ata/ata-all.c
@@ -1188,13 +1188,7 @@ ata_start(struct ata_softc *scp)
     }
 #endif
 #if NATAPICD > 0 || NATAPIFD > 0 || NATAPIST > 0
-    /*
-     * find & call the responsible driver if anything on the ATAPI queue.
-     * check for device busy by polling the DSC bit, if busy, check
-     * for requests to the other device on the channel (if any).
-     * if the other device is an ATA disk it already had its chance above.
-     * if no request can be served, timeout a call to ata_start.
-     */
+    /* find & call the responsible driver if anything on the ATAPI queue */
     if (TAILQ_EMPTY(&scp->atapi_queue)) {
 	if (scp->devices & (ATA_ATAPI_MASTER) && scp->dev_softc[0])
 	    atapi_start((struct atapi_softc *)scp->dev_softc[0]);
@@ -1202,33 +1196,6 @@ ata_start(struct ata_softc *scp)
 	    atapi_start((struct atapi_softc *)scp->dev_softc[1]);
     }
     if ((atapi_request = TAILQ_FIRST(&scp->atapi_queue))) {
-	struct atapi_softc *atp = atapi_request->device;
-	static int32_t interval = 1;
-
-	if (atp->flags & ATAPI_F_DSC_USED) {
-	    outb(atp->controller->ioaddr + ATA_DRIVE, ATA_D_IBM | atp->unit);
-	    DELAY(1);
-	    if (!(inb(atp->controller->ioaddr + ATA_STATUS) & ATA_S_DSC)) {
-		while ((atapi_request = TAILQ_NEXT(atapi_request, chain))) {
-		    if (atapi_request->device->unit != atp->unit) {
-			struct atapi_softc *tmp = atapi_request->device;
-
-			outb(tmp->controller->ioaddr + ATA_DRIVE, 
-			     ATA_D_IBM | tmp->unit);
-			DELAY(1);
-			if (!inb(tmp->controller->ioaddr+ATA_STATUS)&ATA_S_DSC)
-			    atapi_request = NULL;
-			break;
-		    }
-	        }
-	    }
-	    if (!atapi_request) {
-		timeout((timeout_t *)ata_start, atp->controller, interval++);
-		return;
-	    }
-	    else
-		interval = 1;
-	}
 	TAILQ_REMOVE(&scp->atapi_queue, atapi_request, chain);
 	scp->active = ATA_ACTIVE_ATAPI;
 	scp->running = atapi_request;
diff --git a/sys/dev/ata/atapi-all.c b/sys/dev/ata/atapi-all.c
index 56103cf77d39..075081d7844f 100644
--- a/sys/dev/ata/atapi-all.c
+++ b/sys/dev/ata/atapi-all.c
@@ -237,13 +237,6 @@ atapi_transfer(struct atapi_request *request)
     if (request->ccb[0] != ATAPI_REQUEST_SENSE)
 	atp->cmd = request->ccb[0];
 
-    /* flag if we can trust the DSC bit */
-    if (request->ccb[0] == ATAPI_READ || request->ccb[0] == ATAPI_READ_BIG ||
-        request->ccb[0] == ATAPI_WRITE || request->ccb[0] == ATAPI_WRITE_BIG)
-        atp->flags |= ATAPI_F_DSC_USED;
-    else
-	atp->flags &= ~ATAPI_F_DSC_USED;
-
     /* if DMA enabled setup DMA hardware */
     request->flags &= ~ATPR_F_DMA_USED; 
     if ((atp->controller->mode[ATA_DEV(atp->unit)] >= ATA_DMA) &&
diff --git a/sys/dev/ata/atapi-all.h b/sys/dev/ata/atapi-all.h
index 6e5bc5a7a9d5..b3e50916914f 100644
--- a/sys/dev/ata/atapi-all.h
+++ b/sys/dev/ata/atapi-all.h
@@ -148,8 +148,7 @@ struct atapi_softc {
     int8_t			*devname;	/* this devices name */
     int8_t			cmd;		/* last cmd executed */
     u_int32_t			flags;		/* drive flags */
-#define		ATAPI_F_DSC_USED	0x0001
-#define		ATAPI_F_MEDIA_CHANGED	0x0002
+#define		ATAPI_F_MEDIA_CHANGED	0x0001
 
 };
 
diff --git a/sys/dev/ata/atapi-tape.c b/sys/dev/ata/atapi-tape.c
index 53b546e4f26b..2f737c43b2c7 100644
--- a/sys/dev/ata/atapi-tape.c
+++ b/sys/dev/ata/atapi-tape.c
@@ -466,16 +466,10 @@ ast_start(struct atapi_softc *atp)
 
     bzero(ccb, sizeof(ccb));
 
-    if (bp->b_flags & B_READ) {
+    if (bp->b_flags & B_READ)
 	ccb[0] = ATAPI_READ;
-	if (!(stp->flags & ATAPI_F_DSC_USED))
-	    atapi_queue_cmd(stp->atp, ccb, NULL, 0, 0, 2*60, NULL, NULL);
-    } 
-    else {
+    else
 	ccb[0] = ATAPI_WRITE;
-	if (!(stp->flags & ATAPI_F_DSC_USED))
-	    atapi_queue_cmd(stp->atp, ccb, NULL, 0, 0, 2*60, NULL, NULL);
-    } 
     
     bufq_remove(&stp->buf_queue, bp);
     blkcount = bp->b_bcount / stp->blksize;
@@ -488,7 +482,7 @@ ast_start(struct atapi_softc *atp)
     devstat_start_transaction(&stp->stats);
 
     atapi_queue_cmd(stp->atp, ccb, bp->b_data, blkcount * stp->blksize, 
-		    bp->b_flags&B_READ ? ATPR_F_READ : 0, 60, ast_done, bp);
+		    bp->b_flags & B_READ ? ATPR_F_READ : 0, 60, ast_done, bp);
 }
 
 static int32_t