[PATCH net] net: aquantia: Fix aq_vec_isr_legacy() return value

[Dan Carpenter]

The irqreturn_t type is an enum or an unsigned int in GCC.  That
creates to problems because it can't detect if the
self->aq_hw_ops->hw_irq_read() call fails and at the end the function
always returns IRQ_HANDLED.

drivers/net/ethernet/aquantia/atlantic/aq_vec.c:316 aq_vec_isr_legacy() warn: 
unsigned 'err' is never less than zero.
drivers/net/ethernet/aquantia/atlantic/aq_vec.c:329 aq_vec_isr_legacy() warn: 
always true condition '(err >= 0) => (0-u32max >= 0)'

Fixes: 970a2e9864b0 ("net: ethernet: aquantia: Vector operations")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
---
 drivers/net/ethernet/aquantia/atlantic/aq_vec.c | 15 ++++++---------
 1 file changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c 
b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
index 28892b8acd0e..a95c263a45aa 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_vec.c
@@ -306,15 +306,13 @@ irqreturn_t aq_vec_isr_legacy(int irq, void *private)
 {
        struct aq_vec_s *self = private;
        u64 irq_mask = 0U;
-       irqreturn_t err = 0;
+       int err;
 
-       if (!self) {
-               err = -EINVAL;
-               goto err_exit;
-       }
+       if (!self)
+               return IRQ_NONE;
        err = self->aq_hw_ops->hw_irq_read(self->aq_hw, &irq_mask);
        if (err < 0)
-               goto err_exit;
+               return IRQ_NONE;
 
        if (irq_mask) {
                self->aq_hw_ops->hw_irq_disable(self->aq_hw,
@@ -322,11 +320,10 @@ irqreturn_t aq_vec_isr_legacy(int irq, void *private)
                napi_schedule(&self->napi);
        } else {
                self->aq_hw_ops->hw_irq_enable(self->aq_hw, 1U);
-               err = IRQ_NONE;
+               return IRQ_NONE;
        }
 
-err_exit:
-       return err >= 0 ? IRQ_HANDLED : IRQ_NONE;
+       return IRQ_HANDLED;
 }
 
 cpumask_t *aq_vec_get_affinity_mask(struct aq_vec_s *self)
-- 
2.20.1