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* [PATCH AUTOSEL 5.4 077/459] pwm: omap-dmtimer: Simplify error handling
       [not found] <20200214160149.11681-1-sashal@kernel.org>
@ 2020-02-14 15:55 ` Sasha Levin
  2020-02-14 16:00 ` [PATCH AUTOSEL 5.4 353/459] pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional Sasha Levin
  2020-02-14 16:00 ` [PATCH AUTOSEL 5.4 358/459] pwm: Remove set but not set variable 'pwm' Sasha Levin
  2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2020-02-14 15:55 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Uwe Kleine-König, Thierry Reding, Sasha Levin, linux-pwm

From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

[ 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-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 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 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
 	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

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH AUTOSEL 5.4 353/459] pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional
       [not found] <20200214160149.11681-1-sashal@kernel.org>
  2020-02-14 15:55 ` [PATCH AUTOSEL 5.4 077/459] pwm: omap-dmtimer: Simplify error handling Sasha Levin
@ 2020-02-14 16:00 ` Sasha Levin
  2020-02-14 16:00 ` [PATCH AUTOSEL 5.4 358/459] pwm: Remove set but not set variable 'pwm' Sasha Levin
  2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2020-02-14 16:00 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: Uwe Kleine-König, Thierry Reding, Sasha Levin, linux-pwm

From: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>

[ Upstream commit 43efdc8f0e6d7088ec61bd55a73bf853f002d043 ]

In the old code (e.g.) mutex_destroy() was called before
pwmchip_remove(). Between these two calls it is possible that a PWM
callback is used which tries to grab the mutex.

Fixes: 6604c6556db9 ("pwm: Add PWM driver for OMAP using dual-mode timers")
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pwm/pwm-omap-dmtimer.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/pwm/pwm-omap-dmtimer.c b/drivers/pwm/pwm-omap-dmtimer.c
index 6cfeb0e1cc679..e36fcad668a68 100644
--- a/drivers/pwm/pwm-omap-dmtimer.c
+++ b/drivers/pwm/pwm-omap-dmtimer.c
@@ -361,6 +361,11 @@ static int pwm_omap_dmtimer_probe(struct platform_device *pdev)
 static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
 {
 	struct pwm_omap_dmtimer_chip *omap = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = pwmchip_remove(&omap->chip);
+	if (ret)
+		return ret;
 
 	if (pm_runtime_active(&omap->dm_timer_pdev->dev))
 		omap->pdata->stop(omap->dm_timer);
@@ -369,7 +374,7 @@ static int pwm_omap_dmtimer_remove(struct platform_device *pdev)
 
 	mutex_destroy(&omap->mutex);
 
-	return pwmchip_remove(&omap->chip);
+	return 0;
 }
 
 static const struct of_device_id pwm_omap_dmtimer_of_match[] = {
-- 
2.20.1

^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH AUTOSEL 5.4 358/459] pwm: Remove set but not set variable 'pwm'
       [not found] <20200214160149.11681-1-sashal@kernel.org>
  2020-02-14 15:55 ` [PATCH AUTOSEL 5.4 077/459] pwm: omap-dmtimer: Simplify error handling Sasha Levin
  2020-02-14 16:00 ` [PATCH AUTOSEL 5.4 353/459] pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional Sasha Levin
@ 2020-02-14 16:00 ` Sasha Levin
  2 siblings, 0 replies; 3+ messages in thread
From: Sasha Levin @ 2020-02-14 16:00 UTC (permalink / raw)
  To: linux-kernel, stable
  Cc: yu kuai, Uwe Kleine-König, Thierry Reding, Sasha Levin,
	linux-pwm

From: yu kuai <yukuai3@huawei.com>

[ Upstream commit 9871abffc81048e20f02e15d6aa4558a44ad53ea ]

Fixes gcc '-Wunused-but-set-variable' warning:

	drivers/pwm/pwm-pca9685.c: In function ‘pca9685_pwm_gpio_free’:
	drivers/pwm/pwm-pca9685.c:162:21: warning: variable ‘pwm’ set but not used [-Wunused-but-set-variable]

It is never used, and so can be removed. In that case, hold and release
the lock 'pca->lock' can be removed since nothing will be done between
them.

Fixes: e926b12c611c ("pwm: Clear chip_data in pwm_put()")
Signed-off-by: yu kuai <yukuai3@huawei.com>
Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pwm/pwm-pca9685.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/drivers/pwm/pwm-pca9685.c b/drivers/pwm/pwm-pca9685.c
index 168684b02ebce..b07bdca3d510d 100644
--- a/drivers/pwm/pwm-pca9685.c
+++ b/drivers/pwm/pwm-pca9685.c
@@ -159,13 +159,9 @@ static void pca9685_pwm_gpio_set(struct gpio_chip *gpio, unsigned int offset,
 static void pca9685_pwm_gpio_free(struct gpio_chip *gpio, unsigned int offset)
 {
 	struct pca9685 *pca = gpiochip_get_data(gpio);
-	struct pwm_device *pwm;
 
 	pca9685_pwm_gpio_set(gpio, offset, 0);
 	pm_runtime_put(pca->chip.dev);
-	mutex_lock(&pca->lock);
-	pwm = &pca->chip.pwms[offset];
-	mutex_unlock(&pca->lock);
 }
 
 static int pca9685_pwm_gpio_get_direction(struct gpio_chip *chip,
-- 
2.20.1

^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2020-02-14 16:00 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz follow: Atom feed
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     [not found] <20200214160149.11681-1-sashal@kernel.org>
2020-02-14 15:55 ` [PATCH AUTOSEL 5.4 077/459] pwm: omap-dmtimer: Simplify error handling Sasha Levin
2020-02-14 16:00 ` [PATCH AUTOSEL 5.4 353/459] pwm: omap-dmtimer: Remove PWM chip in .remove before making it unfunctional Sasha Levin
2020-02-14 16:00 ` [PATCH AUTOSEL 5.4 358/459] pwm: Remove set but not set variable 'pwm' Sasha Levin

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