On 9/26/20 9:18 PM, William Breathitt Gray wrote:
+static irqreturn_t quad8_irq_handler(int irq, void *quad8iio) +{ + struct quad8_iio *const priv = quad8iio; + const unsigned long base = priv->base; + unsigned long irq_status; + unsigned long channel; + u8 event; + int err; + + irq_status = inb(base + QUAD8_REG_INTERRUPT_STATUS); + if (!irq_status) + return IRQ_NONE; + + for_each_set_bit(channel, &irq_status, QUAD8_NUM_COUNTERS) { + switch (priv->irq_trigger[channel]) { + case 0: + event = COUNTER_EVENT_OVERFLOW; + break; + case 1: + event = COUNTER_EVENT_THRESHOLD; + break; + case 2: + event = COUNTER_EVENT_OVERFLOW_UNDERFLOW; + break; + case 3: + event = COUNTER_EVENT_INDEX; + break; + default: + /* We should never reach here */ + return -EINVAL;
This is not a valid return value for an IRQ handler. Maybe WARN_ONCE instead?
+ } + err = counter_push_event(&priv->counter, event, channel); + if (err) + return err;
Same here. Otherwise, I think we could end up with interrupts in an endless loop since the interrupt would never be cleared.
+ } + + /* Clear pending interrupts on device */ + outb(QUAD8_CHAN_OP_ENABLE_INTERRUPT_FUNC, base + QUAD8_REG_CHAN_OP); + + return IRQ_HANDLED; +} +