Use qc_defer to serialize the two channels Signed-off-by: Alan Cox <alan@xxxxxxxxxx> diff -u --new-file --recursive --exclude-from /usr/src/exclude linux.vanilla-2.6.24/drivers/ata/pata_sl82c105.c linux-2.6.24/drivers/ata/pata_sl82c105.c --- linux.vanilla-2.6.24/drivers/ata/pata_sl82c105.c 2008-01-24 22:58:37.000000000 +0000 +++ linux-2.6.24/drivers/ata/pata_sl82c105.c 2008-01-28 15:44:11.000000000 +0000 @@ -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; - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html