diff options
Diffstat (limited to 'drivers/scsi/g_NCR5380.c')
| -rw-r--r-- | drivers/scsi/g_NCR5380.c | 52 |
1 files changed, 51 insertions, 1 deletions
diff --git a/drivers/scsi/g_NCR5380.c b/drivers/scsi/g_NCR5380.c index 76e37455480e..6d245a7b9363 100644 --- a/drivers/scsi/g_NCR5380.c +++ b/drivers/scsi/g_NCR5380.c @@ -67,6 +67,56 @@ MODULE_PARM_DESC(card, "card type (0=NCR5380, 1=NCR53C400, 2=NCR53C400A, 3=DTC31 MODULE_ALIAS("g_NCR5380_mmio"); MODULE_LICENSE("GPL"); +static void g_NCR5380_trigger_irq(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + + /* + * An interrupt is triggered whenever BSY = false, SEL = true + * and a bit set in the SELECT_ENABLE_REG is asserted on the + * SCSI bus. + * + * Note that the bus is only driven when the phase control signals + * (I/O, C/D, and MSG) match those in the TCR. + */ + NCR5380_write(TARGET_COMMAND_REG, + PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG) & PHASE_MASK)); + NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask); + NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask); + NCR5380_write(INITIATOR_COMMAND_REG, + ICR_BASE | ICR_ASSERT_DATA | ICR_ASSERT_SEL); + + msleep(1); + + NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE); + NCR5380_write(SELECT_ENABLE_REG, 0); + NCR5380_write(TARGET_COMMAND_REG, 0); +} + +/** + * g_NCR5380_probe_irq - find the IRQ of a NCR5380 or equivalent + * @instance: SCSI host instance + * + * Autoprobe for the IRQ line used by the card by triggering an IRQ + * and then looking to see what interrupt actually turned up. + */ + +static int g_NCR5380_probe_irq(struct Scsi_Host *instance) +{ + struct NCR5380_hostdata *hostdata = shost_priv(instance); + int irq_mask, irq; + + NCR5380_read(RESET_PARITY_INTERRUPT_REG); + irq_mask = probe_irq_on(); + g_NCR5380_trigger_irq(instance); + irq = probe_irq_off(irq_mask); + NCR5380_read(RESET_PARITY_INTERRUPT_REG); + + if (irq <= 0) + return NO_IRQ; + return irq; +} + /* * Configure I/O address of 53C400A or DTC436 by writing magic numbers * to ports 0x779 and 0x379. @@ -272,7 +322,7 @@ static int generic_NCR5380_init_one(struct scsi_host_template *tpnt, if (irq != IRQ_AUTO) instance->irq = irq; else - instance->irq = NCR5380_probe_irq(instance, 0xffff); + instance->irq = g_NCR5380_probe_irq(instance); /* Compatibility with documented NCR5380 kernel parameters */ if (instance->irq == 255) |