libata fixes for sparse-found problems

In pata_legacy and pata_winbond we've got bugs - cpu_to_le16() instead
of cpu_to_le32().  Fortunately, both affected suckers are VLB, thus
l-e-only, so we might get away with that unless we hit it with slop == 3
(hadn't checked if playing with badly aligned sg could trigger that).
Still buggy...  Moreover, pata_legacy, pata_winbond and pata_qdi forgot to
initialize pad on the write side of 32bit case in their ->data_xfer().
Hopefully the hardware does't care, but still, sending uninitialized
data to it...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/pata_legacy.c

@@ -271,14 +271,12 @@ static void pdc_data_xfer_vlb(struct ata_device *adev, unsigned char *buf, unsig
 			ioread32_rep(ap->ioaddr.data_addr, buf, buflen >> 2);
 
 		if (unlikely(slop)) {
-			u32 pad;
+			__le32 pad = 0;
 			if (write_data) {
 				memcpy(&pad, buf + buflen - slop, slop);
-				pad = le32_to_cpu(pad);
-				iowrite32(pad, ap->ioaddr.data_addr);
+				iowrite32(le32_to_cpu(pad), ap->ioaddr.data_addr);
 			} else {
-				pad = ioread32(ap->ioaddr.data_addr);
-				pad = cpu_to_le16(pad);
+				pad = cpu_to_le32(ioread32(ap->ioaddr.data_addr));
 				memcpy(buf + buflen - slop, &pad, slop);
 			}
 		}

drivers/ata/pata_qdi.c

@@ -136,14 +136,12 @@ static void qdi_data_xfer(struct ata_device *adev, unsigned char *buf, unsigned
 			ioread32_rep(ap->ioaddr.data_addr, buf, buflen >> 2);
 
 		if (unlikely(slop)) {
-			u32 pad;
+			__le32 pad = 0;
 			if (write_data) {
 				memcpy(&pad, buf + buflen - slop, slop);
-				pad = le32_to_cpu(pad);
-				iowrite32(pad, ap->ioaddr.data_addr);
+				iowrite32(le32_to_cpu(pad), ap->ioaddr.data_addr);
 			} else {
-				pad = ioread32(ap->ioaddr.data_addr);
-				pad = cpu_to_le32(pad);
+				pad = cpu_to_le32(ioread32(ap->ioaddr.data_addr));
 				memcpy(buf + buflen - slop, &pad, slop);
 			}
 		}

drivers/ata/pata_winbond.c

@@ -104,14 +104,12 @@ static void winbond_data_xfer(struct ata_device *adev, unsigned char *buf, unsig
 			ioread32_rep(ap->ioaddr.data_addr, buf, buflen >> 2);
 
 		if (unlikely(slop)) {
-			u32 pad;
+			__le32 pad = 0;
 			if (write_data) {
 				memcpy(&pad, buf + buflen - slop, slop);
-				pad = le32_to_cpu(pad);
-				iowrite32(pad, ap->ioaddr.data_addr);
+				iowrite32(le32_to_cpu(pad), ap->ioaddr.data_addr);
 			} else {
-				pad = ioread32(ap->ioaddr.data_addr);
-				pad = cpu_to_le16(pad);
+				pad = cpu_to_le32(ioread32(ap->ioaddr.data_addr));
 				memcpy(buf + buflen - slop, &pad, slop);
 			}
 		}