From 92ba5d02d993ccf4a87b945779fe052f67c3c334 Mon Sep 17 00:00:00 2001 From: Alan Cox Date: Mon, 28 Jan 2008 16:08:23 +0000 Subject: [PATCH] pata_sl82c105: dual channel support Use qc_defer to serialize the two channels Signed-off-by: Alan Cox Signed-off-by: Jeff Garzik --- drivers/ata/pata_sl82c105.c | 33 +++++++++++++++++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) diff --git a/drivers/ata/pata_sl82c105.c b/drivers/ata/pata_sl82c105.c index 1388cef52c07..81ef207f8265 100644 --- a/drivers/ata/pata_sl82c105.c +++ b/drivers/ata/pata_sl82c105.c @@ -26,7 +26,7 @@ #include #define DRV_NAME "pata_sl82c105" -#define DRV_VERSION "0.3.2" +#define DRV_VERSION "0.3.3" enum { /* @@ -206,6 +206,34 @@ static void sl82c105_bmdma_stop(struct ata_queued_cmd *qc) 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 @@ static struct ata_port_operations sl82c105_port_ops = { .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 @@ static int sl82c105_init_one(struct pci_dev *dev, const struct pci_device_id *id }; /* for now use only the first port */ const struct ata_port_info *ppi[] = { &info_early, - &ata_dummy_port_info }; + NULL }; u32 val; int rev; -- GitLab