libata: make ->scr_read/write callbacks return error code

Convert ->scr_read/write callbacks to return error code to better
indicate failure.  This will help handling of SCR_NOTIFICATION.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 10 insertions, 11 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index ecbc327..5718c24 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -5732,10 +5732,8 @@ int sata_scr_valid(struct ata_port *ap)
  */
 int sata_scr_read(struct ata_port *ap, int reg, u32 *val)
 {
-	if (sata_scr_valid(ap)) {
-		*val = ap->ops->scr_read(ap, reg);
-		return 0;
-	}
+	if (sata_scr_valid(ap))
+		return ap->ops->scr_read(ap, reg, val);
 	return -EOPNOTSUPP;
 }
 
@@ -5757,10 +5755,8 @@ int sata_scr_read(struct ata_port *ap, int reg, u32 *val)
  */
 int sata_scr_write(struct ata_port *ap, int reg, u32 val)
 {
-	if (sata_scr_valid(ap)) {
-		ap->ops->scr_write(ap, reg, val);
-		return 0;
-	}
+	if (sata_scr_valid(ap))
+		return ap->ops->scr_write(ap, reg, val);
 	return -EOPNOTSUPP;
 }
 
@@ -5781,10 +5777,13 @@ int sata_scr_write(struct ata_port *ap, int reg, u32 val)
  */
 int sata_scr_write_flush(struct ata_port *ap, int reg, u32 val)
 {
+	int rc;
+
 	if (sata_scr_valid(ap)) {
-		ap->ops->scr_write(ap, reg, val);
-		ap->ops->scr_read(ap, reg);
-		return 0;
+		rc = ap->ops->scr_write(ap, reg, val);
+		if (rc == 0)
+			rc = ap->ops->scr_read(ap, reg, &val);
+		return rc;
 	}
 	return -EOPNOTSUPP;
 }