of_irq_get_byname() may return 0 as well as negative error number on failure, while the driver only checks for the negative values. The driver would then call request_irq(0, ...) in ti_msgmgr_queue_startup() and never get a valid channel interrupt. Check for 'qinst->irq <= 0' instead and return -ENXIO from ti_msgmgr_queue_setup() and this fail the driver's probe iff of_irq_get_byname() returned 0. Fixes: aace66b170ce ("mailbox: Introduce TI message manager driver") Signed-off-by: Sergei Shtylyov --- drivers/mailbox/ti-msgmgr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) Index: linux/drivers/mailbox/ti-msgmgr.c =================================================================== --- linux.orig/drivers/mailbox/ti-msgmgr.c +++ linux/drivers/mailbox/ti-msgmgr.c @@ -444,12 +444,12 @@ static int ti_msgmgr_queue_setup(int idx "rx_%03d", qinst->queue_id); qinst->irq = of_irq_get_byname(np, of_rx_irq_name); - if (qinst->irq < 0) { + if (qinst->irq <= 0) { dev_crit(dev, "[%d]QID %d PID %d:No IRQ[%s]: %d\n", idx, qinst->queue_id, qinst->proxy_id, of_rx_irq_name, qinst->irq); - return qinst->irq; + return qinst->irq ?: -ENXIO; } /* Allocate usage buffer for rx */ qinst->rx_buff = devm_kzalloc(dev,