pata_sl82c105: dual channel support
Use qc_defer to serialize the two channels
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
diff --git a/drivers/ata/pata_sl82c105.c b/drivers/ata/pata_sl82c105.c
index 1388cef5..81ef207 100644
--- a/drivers/ata/pata_sl82c105.c
+++ b/drivers/ata/pata_sl82c105.c
@@ -26,7 +26,7 @@
#include <linux/libata.h>
#define DRV_NAME "pata_sl82c105"
-#define DRV_VERSION "0.3.2"
+#define DRV_VERSION "0.3.3"
enum {
/*
@@ -206,6 +206,34 @@
sl82c105_set_piomode(ap, qc->dev);
}
+/**
+ * sl82c105_qc_defer - implement serialization
+ * @qc: command
+ *
+ * We must issue one command per host not per channel because
+ * of the reset bug.
+ *
+ * Q: is the scsi host lock sufficient ?
+ */
+
+static int sl82c105_qc_defer(struct ata_queued_cmd *qc)
+{
+ struct ata_host *host = qc->ap->host;
+ struct ata_port *alt = host->ports[1 ^ qc->ap->port_no];
+ int rc;
+
+ /* First apply the usual rules */
+ rc = ata_std_qc_defer(qc);
+ if (rc != 0)
+ return rc;
+
+ /* Now apply serialization rules. Only allow a command if the
+ other channel state machine is idle */
+ if (alt && alt->qc_active)
+ return ATA_DEFER_PORT;
+ return 0;
+}
+
static struct scsi_host_template sl82c105_sht = {
.module = THIS_MODULE,
.name = DRV_NAME,
@@ -245,6 +273,7 @@
.bmdma_stop = sl82c105_bmdma_stop,
.bmdma_status = ata_bmdma_status,
+ .qc_defer = sl82c105_qc_defer,
.qc_prep = ata_qc_prep,
.qc_issue = ata_qc_issue_prot,
@@ -312,7 +341,7 @@
};
/* for now use only the first port */
const struct ata_port_info *ppi[] = { &info_early,
- &ata_dummy_port_info };
+ NULL };
u32 val;
int rev;