[PATCH -next] bus: mhi: ep: Fix an ignored error return from ida_alloc()

[Yang Li <yang.lee@linux.alibaba.com>]

The return from the call to ida_alloc() is int, it can be a negative
error code, however this is being assigned to an unsigned int variable
'mhi_cntrl->index', so assign the value to 'ret' concurrently to solve
this problem without affecting other functions.

Eliminate the following coccicheck warning:
./drivers/bus/mhi/ep/main.c:1422:5-21: WARNING: Unsigned expression
compared with zero: mhi_cntrl -> index < 0

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
---
 drivers/bus/mhi/ep/main.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/drivers/bus/mhi/ep/main.c b/drivers/bus/mhi/ep/main.c
index 3e98107f08c4..b27e90d97029 100644
--- a/drivers/bus/mhi/ep/main.c
+++ b/drivers/bus/mhi/ep/main.c
@@ -1418,11 +1418,9 @@ int mhi_ep_register_controller(struct mhi_ep_cntrl *mhi_cntrl,
 	mhi_ep_mmio_set_env(mhi_cntrl, MHI_EE_AMSS);
 
 	/* Set controller index */
-	mhi_cntrl->index = ida_alloc(&mhi_ep_cntrl_ida, GFP_KERNEL);
-	if (mhi_cntrl->index < 0) {
-		ret = mhi_cntrl->index;
+	mhi_cntrl->index = ret = ida_alloc(&mhi_ep_cntrl_ida, GFP_KERNEL);
+	if (ret < 0)
 		goto err_destroy_wq;
-	}
 
 	irq_set_status_flags(mhi_cntrl->irq, IRQ_NOAUTOEN);
 	ret = request_irq(mhi_cntrl->irq, mhi_ep_irq, IRQF_TRIGGER_HIGH,
-- 
2.20.1.7.g153144c