i2c: cadence: add IRQ check

The driver neglects to check the result of platform_get_irq()'s call and
blithely passes the negative error codes to devm_request_irq() (which
takes *unsigned* IRQ #), causing it to fail with -EINVAL, overriding
an original error code.  Stop calling devm_request_irq() with invalid
IRQ #s.

Fixes: df8eb5691c48 ("i2c: Add driver for Cadence I2C controller")
Signed-off-by: Sergey Shtylyov <s.shtylyov@omprussia.ru>
Signed-off-by: Wolfram Sang <wsa@kernel.org>

diff --git a/drivers/i2c/busses/i2c-cadence.c b/drivers/i2c/busses/i2c-cadence.c
index e8eae87..c1bbc4c 100644 (file)
--- a/drivers/i2c/busses/i2c-cadence.c
+++ b/drivers/i2c/busses/i2c-cadence.c
@@ -1200,7 +1200,10 @@ static int cdns_i2c_probe(struct platform_device *pdev)
        if (IS_ERR(id->membase))
                return PTR_ERR(id->membase);
 
-       id->irq = platform_get_irq(pdev, 0);
+       ret = platform_get_irq(pdev, 0);
+       if (ret < 0)
+               return ret;
+       id->irq = ret;
 
        id->adap.owner = THIS_MODULE;
        id->adap.dev.of_node = pdev->dev.of_node;