pata_cmd640: implement sff_irq_check() method

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/pata_cmd640.c

@@ -161,6 +161,17 @@ static int cmd640_port_start(struct ata_port *ap)
 	return 0;
 }
 
+static bool cmd640_sff_irq_check(struct ata_port *ap)
+{
+	struct pci_dev *pdev	= to_pci_dev(ap->host->dev);
+	int irq_reg		= ap->port_no ? ARTIM23 : CFR;
+	u8  irq_stat, irq_mask	= ap->port_no ? 0x10 : 0x04;
+
+	pci_read_config_byte(pdev, irq_reg, &irq_stat);
+
+	return irq_stat & irq_mask;
+}
+
 static struct scsi_host_template cmd640_sht = {
 	ATA_PIO_SHT(DRV_NAME),
 };
@@ -169,6 +180,7 @@ static struct ata_port_operations cmd640_port_ops = {
 	.inherits	= &ata_sff_port_ops,
 	/* In theory xfer_noirq is not needed once we kill the prefetcher */
 	.sff_data_xfer	= ata_sff_data_xfer_noirq,
+	.sff_irq_check	= cmd640_sff_irq_check,
 	.qc_issue	= cmd640_qc_issue,
 	.cable_detect	= ata_cable_40wire,
 	.set_piomode	= cmd640_set_piomode,