[PATCH net 1/3] net: dsa: microchip: Fix checks on irq_find_mapping()

From: Bastien Curutchet (Schneider Electric)

Date: Fri Oct 31 2025 - 12:05:47 EST


irq_find_mapping() returns a positive IRQ number or 0 if no IRQ is found
but it never returns a negative value. However, on each
irq_find_mapping() call, we verify that the returned value isn't
negative.

Fix the irq_find_mapping() checks to enter error paths when 0 is
returned. Return -EINVAL in such cases.

Signed-off-by: Bastien Curutchet (Schneider Electric) <bastien.curutchet@xxxxxxxxxxx>
---
drivers/net/dsa/microchip/ksz_common.c | 8 ++++----
drivers/net/dsa/microchip/ksz_ptp.c | 4 ++--
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/net/dsa/microchip/ksz_common.c b/drivers/net/dsa/microchip/ksz_common.c
index a962055bfdbd8fbfc135b2dec73c222a213985c4..3a4516d32aa5f99109853ed400e64f8f7e2d8016 100644
--- a/drivers/net/dsa/microchip/ksz_common.c
+++ b/drivers/net/dsa/microchip/ksz_common.c
@@ -2583,8 +2583,8 @@ static int ksz_irq_phy_setup(struct ksz_device *dev)

irq = irq_find_mapping(dev->ports[port].pirq.domain,
PORT_SRC_PHY_INT);
- if (irq < 0) {
- ret = irq;
+ if (!irq) {
+ ret = -EINVAL;
goto out;
}
ds->user_mii_bus->irq[phy] = irq;
@@ -2948,8 +2948,8 @@ static int ksz_pirq_setup(struct ksz_device *dev, u8 p)
snprintf(pirq->name, sizeof(pirq->name), "port_irq-%d", p);

pirq->irq_num = irq_find_mapping(dev->girq.domain, p);
- if (pirq->irq_num < 0)
- return pirq->irq_num;
+ if (!pirq->irq_num)
+ return -EINVAL;

return ksz_irq_common_setup(dev, pirq);
}
diff --git a/drivers/net/dsa/microchip/ksz_ptp.c b/drivers/net/dsa/microchip/ksz_ptp.c
index 35fc21b1ee48a47daa278573bfe8749c7b42c731..c8bfbe5e2157323ecf29149d1907b77e689aa221 100644
--- a/drivers/net/dsa/microchip/ksz_ptp.c
+++ b/drivers/net/dsa/microchip/ksz_ptp.c
@@ -1139,8 +1139,8 @@ int ksz_ptp_irq_setup(struct dsa_switch *ds, u8 p)
irq_create_mapping(ptpirq->domain, irq);

ptpirq->irq_num = irq_find_mapping(port->pirq.domain, PORT_SRC_PTP_INT);
- if (ptpirq->irq_num < 0) {
- ret = ptpirq->irq_num;
+ if (!ptpirq->irq_num) {
+ ret = -EINVAL;
goto out;
}


--
2.51.0