Coverity: qcom_swrm_irq_handler(): Control flow issues

Hello!

This is an experimental semi-automated report about issues detected by Coverity from a scan of next-20210331 as part of the linux-next scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan

You're getting this email because you were associated with the identified lines of code (noted below) that were touched by commits:

None
c7d49c76d1d5 ("soundwire: qcom: add support to new interrupts")

Coverity reported the following:

*** CID 1503584: Control flow issues (NO_EFFECT) /drivers/soundwire/qcom.c: 446 in qcom_swrm_irq_handler()
440 if (!value)
441 continue;
442

443     			switch (value) {
444     			case SWRM_INTERRUPT_STATUS_SLAVE_PEND_IRQ:
445     				devnum = qcom_swrm_get_alert_slave_dev_num(swrm);
vvv     CID 1503584:  Control flow issues  (NO_EFFECT)
vvv     This less-than-zero comparison of an unsigned value is never true. "devnum < 0".
446     				if (devnum < 0) {
447     					dev_err_ratelimited(swrm->dev,
448     					    "no slave alert found.spurious interrupt\n");
449     				} else {
450     					sdw_handle_slave_status(&swrm->bus, swrm->status);
451     				}

If this is a false positive, please let us know so we can mark it as such, or teach the Coverity rules to be smarter. If not, please make sure fixes get into linux-next. :) For patches fixing this, please include these lines (but double-check the "Fixes" first):

Addresses-Coverity-ID: 1503584 ("Control flow issues")

Thanks for your attention!

Coverity-bot