libata: update ->data_xfer hook for ATAPI
Depending on how many bytes are transferred as a unit, PIO data
transfer may consume more bytes than requested. Knowing how much
data is consumed is necessary to determine how much is left for
draining. This patch update ->data_xfer such that it returns the
number of consumed bytes.
While at it, it also makes the following changes.
* s/adev/dev/
* use READ/WRITE constants for rw indication
* misc clean ups
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_scc.c b/drivers/ata/pata_scc.c
index ea2ef9f..55055b2 100644
--- a/drivers/ata/pata_scc.c
+++ b/drivers/ata/pata_scc.c
@@ -768,45 +768,47 @@
/**
* scc_data_xfer - Transfer data by PIO
- * @adev: device for this I/O
+ * @dev: device for this I/O
* @buf: data buffer
* @buflen: buffer length
- * @write_data: read/write
+ * @rw: read/write
*
* Note: Original code is ata_data_xfer().
*/
-static void scc_data_xfer (struct ata_device *adev, unsigned char *buf,
- unsigned int buflen, int write_data)
+static unsigned int scc_data_xfer (struct ata_device *dev, unsigned char *buf,
+ unsigned int buflen, int rw)
{
- struct ata_port *ap = adev->link->ap;
+ struct ata_port *ap = dev->link->ap;
unsigned int words = buflen >> 1;
unsigned int i;
u16 *buf16 = (u16 *) buf;
void __iomem *mmio = ap->ioaddr.data_addr;
/* Transfer multiple of 2 bytes */
- if (write_data) {
- for (i = 0; i < words; i++)
- out_be32(mmio, cpu_to_le16(buf16[i]));
- } else {
+ if (rw == READ)
for (i = 0; i < words; i++)
buf16[i] = le16_to_cpu(in_be32(mmio));
- }
+ else
+ for (i = 0; i < words; i++)
+ out_be32(mmio, cpu_to_le16(buf16[i]));
/* Transfer trailing 1 byte, if any. */
if (unlikely(buflen & 0x01)) {
u16 align_buf[1] = { 0 };
unsigned char *trailing_buf = buf + buflen - 1;
- if (write_data) {
- memcpy(align_buf, trailing_buf, 1);
- out_be32(mmio, cpu_to_le16(align_buf[0]));
- } else {
+ if (rw == READ) {
align_buf[0] = le16_to_cpu(in_be32(mmio));
memcpy(trailing_buf, align_buf, 1);
+ } else {
+ memcpy(align_buf, trailing_buf, 1);
+ out_be32(mmio, cpu_to_le16(align_buf[0]));
}
+ words++;
}
+
+ return words << 1;
}
/**