[PATCH 4.14 023/164] iio: adc: cpcap: fix incorrect validation

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Pan Bian <bianpan2016@xxxxxxx>

commit 81b039ec36a41a5451e1e36f05bb055eceab1dc8 upstream.

Function platform_get_irq_byname() returns a negative error code on
failure, and a zero or positive number on success. However, in function
cpcap_adc_probe(), positive IRQ numbers are also taken as error cases.
Use "if (ddata->irq < 0)" instead of "if (!ddata->irq)" to validate the
return value of platform_get_irq_byname().

Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
Fixes: 25ec249632d50 ("iio: adc: cpcap: Add minimal support for CPCAP PMIC ADC")
Reviewed-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxxxx>
Acked-by: Tony Lindgren <tony@xxxxxxxxxxx>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/iio/adc/cpcap-adc.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/iio/adc/cpcap-adc.c
+++ b/drivers/iio/adc/cpcap-adc.c
@@ -1012,7 +1012,7 @@ static int cpcap_adc_probe(struct platfo
 	platform_set_drvdata(pdev, indio_dev);
 
 	ddata->irq = platform_get_irq_byname(pdev, "adcdone");
-	if (!ddata->irq)
+	if (ddata->irq < 0)
 		return -ENODEV;
 
 	error = devm_request_threaded_irq(&pdev->dev, ddata->irq, NULL,