[PATCH v2 09/32] swim: Recalibrate when drive is probed

[Finn Thain]

Track zero recalibration can be slow and is normally done only once i.e.
during system POST or boot-up. Recalibrate once after the drive is probed
rather than every time the device is opened. Don't register the drive if
recalibration fails. Park the heads before ejecting.

Reviewed-by: Laurent Vivier <laurent@xxxxxxxxx>
Fixes: 8852ecd97488 ("m68k: mac - Add SWIM floppy support")
Signed-off-by: Finn Thain <fthain@xxxxxxxxxxxxxx>
---
Changed since v1:
 - Refactor swim_add_floppy() slightly. Start spindle motor before
   recalibration if a disk is loaded.
 - Change return type of swim_add_floppy() to void.
 - Park heads at track 40 because that's what MacOS does.
---
 drivers/block/swim.c | 37 +++++++++++++++++--------------------
 1 file changed, 17 insertions(+), 20 deletions(-)

diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index 6a49fc51f5d2..9abf93bc0980 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -412,6 +412,7 @@ static inline int swim_track00(struct swim __iomem *base)
 	if (swim_readbit(base, TRACK_ZERO))
 		return 0;
 
+	pr_err("swim: track zero recalibration failed\n");
 	return -1;
 }
 
@@ -456,6 +457,7 @@ static int floppy_eject(struct floppy_state *fs)
 	struct swim __iomem *base = fs->swd->base;
 
 	swim_drive(base, fs->location);
+	swim_track(fs, 40);
 	swim_motor(base, OFF);
 	swim_eject(base);
 	swim_drive(base, NO_DRIVE);
@@ -596,13 +598,6 @@ static void setup_medium(struct floppy_state *fs)
 		struct floppy_struct *g;
 		fs->disk_in = 1;
 		fs->write_protected = swim_readbit(base, WRITE_PROT);
-
-		if (swim_track00(base))
-			printk(KERN_ERR
-				"SWIM: cannot move floppy head to track 0\n");
-
-		swim_track00(base);
-
 		fs->type = swim_readbit(base, TWOMEG_MEDIA) ?
 			HD_MEDIA : DD_MEDIA;
 		fs->head_number = swim_readbit(base, SINGLE_SIDED) ? 1 : 2;
@@ -610,7 +605,6 @@ static void setup_medium(struct floppy_state *fs)
 		fs->total_secs = g->size;
 		fs->secpercyl = g->head * g->sect;
 		fs->secpertrack = g->sect;
-		fs->track = 0;
 	} else {
 		fs->disk_in = 0;
 	}
@@ -759,24 +753,33 @@ static const struct block_device_operations floppy_fops = {
 	.check_events	 = floppy_check_events,
 };
 
-static int swim_add_floppy(struct swim_priv *swd, enum drive_location location)
+static void swim_add_floppy(struct swim_priv *swd, enum drive_location location)
 {
 	struct floppy_state *fs = &swd->unit[swd->floppy_count];
 	struct swim __iomem *base = swd->base;
 
-	fs->location = location;
+	swim_drive(base, location);
+	if (!swim_readbit(base, DRIVE_PRESENT) ||
+	    swim_readbit(base, ONEMEG_DRIVE))
+		goto out;
+	if (swim_readbit(base, DISK_IN))
+		swim_motor(base, ON);
+	if (swim_track00(base))
+		goto out;
 
-	swim_motor(base, OFF);
+	fs->location = location;
 
 	fs->type = HD_MEDIA;
 	fs->head_number = 2;
 
 	fs->ref_count = 0;
 	fs->ejected = 1;
+	fs->track = 0;
 
 	swd->floppy_count++;
 
-	return 0;
+out:
+	swim_motor(base, OFF);
 }
 
 static const struct blk_mq_ops swim_mq_ops = {
@@ -825,14 +828,8 @@ static int swim_floppy_init(struct platform_device *pdev)
 
 	/* scan floppy drives */
 
-	swim_drive(base, INTERNAL_DRIVE);
-	if (swim_readbit(base, DRIVE_PRESENT) &&
-	    !swim_readbit(base, ONEMEG_DRIVE))
-		swim_add_floppy(swd, INTERNAL_DRIVE);
-	swim_drive(base, EXTERNAL_DRIVE);
-	if (swim_readbit(base, DRIVE_PRESENT) &&
-	    !swim_readbit(base, ONEMEG_DRIVE))
-		swim_add_floppy(swd, EXTERNAL_DRIVE);
+	swim_add_floppy(swd, INTERNAL_DRIVE);
+	swim_add_floppy(swd, EXTERNAL_DRIVE);
 	swim_drive(base, NO_DRIVE);
 
 	/* register floppy drives */
-- 
2.52.0