[PATCH v2 1/6] i2c: cadence: add IRQ check

[Sergey Shtylyov]

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 at omprussia.ru>

---
Changes in version 2:
- new patch.

 drivers/i2c/busses/i2c-cadence.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

Index: linux/drivers/i2c/busses/i2c-cadence.c
===================================================================
--- linux.orig/drivers/i2c/busses/i2c-cadence.c
+++ linux/drivers/i2c/busses/i2c-cadence.c
@@ -1200,7 +1200,10 @@ static int cdns_i2c_probe(struct platfor
 	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;