[PATCH 5.5 075/399] pwm: omap-dmtimer: Simplify error handling

From: Greg Kroah-Hartman
Date: Fri Feb 21 2020 - 02:48:24 EST


From: Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx>

[ Upstream commit c4cf7aa57eb83b108d2d9c6c37c143388fee2a4d ]

Instead of doing error handling in the middle of ->probe(), move error
handling and freeing the reference to timer to the end.

This fixes a resource leak as dm_timer wasn't freed when allocating
*omap failed.

Implementation note: The put: label was never reached without a goto and
ret being unequal to 0, so the removed return statement is fine.

Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx>
Signed-off-by: Thierry Reding <thierry.reding@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/pwm/pwm-omap-dmtimer.c | 28 +++++++++++++++++++---------
1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c
index 00772fc534906..6cfeb0e1cc679 100644
--- a/drivers/pwm/pwm-omap-dmtimer.c
+++ b/drivers/pwm/pwm-omap-dmtimer.c
@@ -298,15 +298,10 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
goto put;
}

-put:
- of_node_put(timer);
- if (ret < 0)
- return ret;
-
omap = devm_kzalloc(&pdev->dev, sizeof(*omap), GFP_KERNEL);
if (!omap) {
- pdata->free(dm_timer);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto err_alloc_omap;
}

omap->pdata = pdata;
@@ -339,13 +334,28 @@ put:
ret = pwmchip_add(&omap->chip);
if (ret < 0) {
dev_err(&pdev->dev, "failed to register PWM\n");
- omap->pdata->free(omap->dm_timer);
- return ret;
+ goto err_pwmchip_add;
}

+ of_node_put(timer);
+
platform_set_drvdata(pdev, omap);

return 0;
+
+err_pwmchip_add:
+
+ /*
+ * *omap is allocated using devm_kzalloc,
+ * so no free necessary here
+ */
+err_alloc_omap:
+
+ pdata->free(dm_timer);
+put:
+ of_node_put(timer);
+
+ return ret;
}

static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
--
2.20.1