diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index 63ae23b..e63c1ff 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -278,7 +278,7 @@
 }
 
 static const struct ata_xfer_ent {
-	unsigned int shift, bits;
+	int shift, bits;
 	u8 base;
 } ata_xfer_tbl[] = {
 	{ ATA_SHIFT_PIO, ATA_BITS_PIO, XFER_PIO_0 },