+/*
+ * Interrupt handler
+ */
+static irqreturn_t snd_via8233_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ via82xx_t *chip = dev_id;
+ unsigned int status;
+ unsigned int i;
+ int irqreturn = 0;
+
+ /* check status for each stream */
+ spin_lock(&chip->reg_lock);
+ status = inl(VIAREG(chip, SGD_SHADOW));
+
+ for (i = 0; i < chip->num_devs; i++) {
+ viadev_t *viadev = &chip->devs[i];
+ snd_pcm_substream_t *substream;
+ unsigned char c_status, shadow_status;
+
+ shadow_status = (status >> viadev->shadow_shift) &
+ (VIA8233_SHADOW_STAT_ACTIVE|VIA_REG_STAT_EOL|
+ VIA_REG_STAT_FLAG);
+ c_status = shadow_status & (VIA_REG_STAT_EOL|VIA_REG_STAT_FLAG);
+ if (!c_status)
+ continue;
+
+ substream = viadev->substream;
+ if (substream && viadev->running) {
+ /*
+ * Update hwptr_done based on 'period elapsed'
+ * interrupts. We'll use it, when the chip returns 0
+ * for OFFSET_CURR_COUNT.
+ */
+ if (c_status & VIA_REG_STAT_EOL)
+ viadev->hwptr_done = 0;
+ else
+ viadev->hwptr_done += viadev->fragsize;
+ viadev->in_interrupt = c_status;
+ if (shadow_status & VIA8233_SHADOW_STAT_ACTIVE)
+ viadev->in_interrupt |= VIA_REG_STAT_ACTIVE;
+ spin_unlock(&chip->reg_lock);
+
+ snd_pcm_period_elapsed(substream);
+
+ spin_lock(&chip->reg_lock);
+ viadev->in_interrupt = 0;
+ }
+ outb(c_status, VIADEV_REG(viadev, OFFSET_STATUS)); /* ack */
+ irqreturn = 1;
+ }
+ spin_unlock(&chip->reg_lock);
+ return IRQ_RETVAL(irqreturn);
+}
+