[PATCH] spi: mpc52xx: clean up interrupt handling

[Johan Hovold <johan@kernel.org>]

The driver is relying on the assumption that the invalid interrupt 0 can
be freed without any side effects, but that is not the case on
architectures like x86 where it would trigger a warning about freeing an
already free interrupt.

This should not cause any trouble on powerpc where this driver is used,
but make the code more portable (and obviously correct) by making sure
that the interrupts have been requested before freeing them.

Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/spi/spi-mpc52xx.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c
index 924d820448fb..04c2270cd2cf 100644
--- a/drivers/spi/spi-mpc52xx.c
+++ b/drivers/spi/spi-mpc52xx.c
@@ -472,13 +472,15 @@ static int mpc52xx_spi_probe(struct platform_device *op)
 	if (ms->irq0 && ms->irq1) {
 		rc = request_irq(ms->irq0, mpc52xx_spi_irq, 0,
 				  "mpc5200-spi-modf", ms);
-		rc |= request_irq(ms->irq1, mpc52xx_spi_irq, 0,
-				  "mpc5200-spi-spif", ms);
-		if (rc) {
-			free_irq(ms->irq0, ms);
-			free_irq(ms->irq1, ms);
-			ms->irq0 = ms->irq1 = 0;
+		if (rc == 0) {
+			rc = request_irq(ms->irq1, mpc52xx_spi_irq, 0,
+					 "mpc5200-spi-spif", ms);
+			if (rc)
+				free_irq(ms->irq0, ms);
 		}
+
+		if (rc)
+			ms->irq0 = ms->irq1 = 0;
 	} else {
 		/* operate in polled mode */
 		ms->irq0 = ms->irq1 = 0;
@@ -498,8 +500,10 @@ static int mpc52xx_spi_probe(struct platform_device *op)
 
  err_register:
 	dev_err(&ms->host->dev, "initialization failed\n");
-	free_irq(ms->irq0, ms);
-	free_irq(ms->irq1, ms);
+	if (ms->irq0) {
+		free_irq(ms->irq0, ms);
+		free_irq(ms->irq1, ms);
+	}
 	cancel_work_sync(&ms->work);
  err_gpio:
 	while (i-- > 0)
@@ -522,8 +526,10 @@ static void mpc52xx_spi_remove(struct platform_device *op)
 
 	spi_unregister_controller(host);
 
-	free_irq(ms->irq0, ms);
-	free_irq(ms->irq1, ms);
+	if (ms->irq0) {
+		free_irq(ms->irq0, ms);
+		free_irq(ms->irq1, ms);
+	}
 
 	cancel_work_sync(&ms->work);
 
-- 
2.53.0