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_ixp4xx_cf.c b/drivers/ata/pata_ixp4xx_cf.c
index 120b5bf..030878f 100644
--- a/drivers/ata/pata_ixp4xx_cf.c
+++ b/drivers/ata/pata_ixp4xx_cf.c
@@ -42,13 +42,13 @@
return 0;
}
-static void ixp4xx_mmio_data_xfer(struct ata_device *adev, unsigned char *buf,
- unsigned int buflen, int write_data)
+static unsigned int ixp4xx_mmio_data_xfer(struct ata_device *dev,
+ unsigned char *buf, unsigned int buflen, int rw)
{
unsigned int i;
unsigned int words = buflen >> 1;
u16 *buf16 = (u16 *) buf;
- struct ata_port *ap = adev->link->ap;
+ struct ata_port *ap = dev->link->ap;
void __iomem *mmio = ap->ioaddr.data_addr;
struct ixp4xx_pata_data *data = ap->host->dev->platform_data;
@@ -59,30 +59,32 @@
udelay(100);
/* Transfer multiple of 2 bytes */
- if (write_data) {
- for (i = 0; i < words; i++)
- writew(buf16[i], mmio);
- } else {
+ if (rw == READ)
for (i = 0; i < words; i++)
buf16[i] = readw(mmio);
- }
+ else
+ for (i = 0; i < words; i++)
+ writew(buf16[i], mmio);
/* 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);
- writew(align_buf[0], mmio);
- } else {
+ if (rw == READ) {
align_buf[0] = readw(mmio);
memcpy(trailing_buf, align_buf, 1);
+ } else {
+ memcpy(align_buf, trailing_buf, 1);
+ writew(align_buf[0], mmio);
}
+ words++;
}
udelay(100);
*data->cs0_cfg |= 0x01;
+
+ return words << 1;
}
static struct scsi_host_template ixp4xx_sht = {