1 files changed, 42 insertions, 30 deletions

diff --git a/drivers/ide/ide-lib.c b/drivers/ide/ide-lib.c
index 074bb32a4a40..92a6c7bcf527 100644
--- a/drivers/ide/ide-lib.c
+++ b/drivers/ide/ide-lib.c
@@ -249,12 +249,34 @@ static int ide_scan_pio_blacklist (char *model)
 	return -1;
 }
 
+unsigned int ide_pio_cycle_time(ide_drive_t *drive, u8 pio)
+{
+	struct hd_driveid *id = drive->id;
+	int cycle_time = 0;
+
+	if (id->field_valid & 2) {
+		if (id->capability & 8)
+			cycle_time = id->eide_pio_iordy;
+		else
+			cycle_time = id->eide_pio;
+	}
+
+	/* conservative "downgrade" for all pre-ATA2 drives */
+	if (pio < 3) {
+		if (cycle_time && cycle_time < ide_pio_timings[pio].cycle_time)
+			cycle_time = 0; /* use standard timing */
+	}
+
+	return cycle_time ? cycle_time : ide_pio_timings[pio].cycle_time;
+}
+
+EXPORT_SYMBOL_GPL(ide_pio_cycle_time);
+
 /**
  *	ide_get_best_pio_mode	-	get PIO mode from drive
  *	@drive: drive to consider
  *	@mode_wanted: preferred mode
  *	@max_mode: highest allowed mode
- *	@d: PIO data
  *
  *	This routine returns the recommended PIO settings for a given drive,
  *	based on the drive->id information and the ide_pio_blacklist[].
@@ -263,22 +285,18 @@ static int ide_scan_pio_blacklist (char *model)
  *	This is used by most chipset support modules when "auto-tuning".
  */
 
-u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode, ide_pio_data_t *d)
+u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
 {
 	int pio_mode;
-	int cycle_time = 0;
-	int use_iordy = 0;
 	struct hd_driveid* id = drive->id;
 	int overridden  = 0;
 
-	if (mode_wanted != 255) {
-		pio_mode = mode_wanted;
-		use_iordy = (pio_mode > 2);
-	} else if (!drive->id) {
-		pio_mode = 0;
-	} else if ((pio_mode = ide_scan_pio_blacklist(id->model)) != -1) {
-		overridden = 1;
-		use_iordy = (pio_mode > 2);
+	if (mode_wanted != 255)
+		return min_t(u8, mode_wanted, max_mode);
+
+	if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0 &&
+	    (pio_mode = ide_scan_pio_blacklist(id->model)) != -1) {
+		printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
 	} else {
 		pio_mode = id->tPIO;
 		if (pio_mode > 2) {	/* 2 is maximum allowed tPIO value */
@@ -286,9 +304,7 @@ u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode, ide_p
 			overridden = 1;
 		}
 		if (id->field_valid & 2) {	  /* drive implements ATA2? */
-			if (id->capability & 8) { /* drive supports use_iordy? */
-				use_iordy = 1;
-				cycle_time = id->eide_pio_iordy;
+			if (id->capability & 8) { /* IORDY supported? */
 				if (id->eide_pio_modes & 7) {
 					overridden = 0;
 					if (id->eide_pio_modes & 4)
@@ -298,31 +314,27 @@ u8 ide_get_best_pio_mode (ide_drive_t *drive, u8 mode_wanted, u8 max_mode, ide_p
 					else
 						pio_mode = 3;
 				}
-			} else {
-				cycle_time = id->eide_pio;
 			}
 		}
 
+		if (overridden)
+			printk(KERN_INFO "%s: tPIO > 2, assuming tPIO = 2\n",
+					 drive->name);
+
 		/*
 		 * Conservative "downgrade" for all pre-ATA2 drives
 		 */
-		if (pio_mode && pio_mode < 4) {
+		if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_DOWNGRADE) == 0 &&
+		    pio_mode && pio_mode < 4) {
 			pio_mode--;
-			overridden = 1;
-			if (cycle_time && cycle_time < ide_pio_timings[pio_mode].cycle_time)
-				cycle_time = 0; /* use standard timing */
+			printk(KERN_INFO "%s: applying conservative "
+					 "PIO \"downgrade\"\n", drive->name);
 		}
 	}
-	if (pio_mode > max_mode) {
+
+	if (pio_mode > max_mode)
 		pio_mode = max_mode;
-		cycle_time = 0;
-	}
-	if (d) {
-		d->pio_mode = pio_mode;
-		d->cycle_time = cycle_time ? cycle_time : ide_pio_timings[pio_mode].cycle_time;
-		d->use_iordy = use_iordy;
-		d->overridden = overridden;
-	}
+
 	return pio_mode;
 }