linux-kernel - [PATCH v2 14/79] media: am437x: fix pm_runtime_get

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Message-Id: <98c638ac1c2c85c08afc14d63cface1cdbc508bf.1619518193.git.mchehab+huawei@kernel.org>
Date:   Tue, 27 Apr 2021 12:12:41 +0200
From:   Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
To:     unlisted-recipients:; (no To-header on input)
Cc:     linuxarm@...wei.com, mauro.chehab@...wei.com,
        Mauro Carvalho Chehab <mchehab+huawei@...nel.org>,
        "Lad, Prabhakar" <prabhakar.csengg@...il.com>,
        Mauro Carvalho Chehab <mchehab@...nel.org>,
        linux-kernel@...r.kernel.org, linux-media@...r.kernel.org
Subject: [PATCH v2 14/79] media: am437x: fix pm_runtime_get_sync() usage count

The pm_runtime_get_sync() internally increments the
dev->power.usage_count without decrementing it, even on errors.
Replace it by the new pm_runtime_resume_and_get(), introduced by:
commit dd8088d5a896 ("PM: runtime: Add pm_runtime_resume_and_get to deal with usage counter")
in order to properly decrement the usage counter and avoid memory
leaks.

While here, ensure that the driver will check if PM runtime
resumed at vpfe_initialize_device().

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
---
 drivers/media/platform/am437x/am437x-vpfe.c | 22 +++++++++++++++------
 1 file changed, 16 insertions(+), 6 deletions(-)

diff --git a/drivers/media/platform/am437x/am437x-vpfe.c b/drivers/media/platform/am437x/am437x-vpfe.c
index 6cdc77dda0e4..bced526f30f2 100644
--- a/drivers/media/platform/am437x/am437x-vpfe.c
+++ b/drivers/media/platform/am437x/am437x-vpfe.c
@@ -1021,7 +1021,9 @@ static int vpfe_initialize_device(struct vpfe_device *vpfe)
 	if (ret)
 		return ret;
 
-	pm_runtime_get_sync(vpfe->pdev);
+	ret = pm_runtime_resume_and_get(vpfe->pdev);
+	if (ret < 0)
+		return ret;
 
 	vpfe_config_enable(&vpfe->ccdc, 1);
 
@@ -2443,7 +2445,11 @@ static int vpfe_probe(struct platform_device *pdev)
 	pm_runtime_enable(&pdev->dev);
 
 	/* for now just enable it here instead of waiting for the open */
-	pm_runtime_get_sync(&pdev->dev);
+	ret = pm_runtime_resume_and_get(&pdev->dev);
+	if (ret < 0) {
+		vpfe_err(vpfe, "Unable to resume device.\n");
+		goto probe_out_v4l2_unregister;
+	}
 
 	vpfe_ccdc_config_defaults(ccdc);
 
@@ -2527,10 +2533,11 @@ static int vpfe_suspend(struct device *dev)
 {
 	struct vpfe_device *vpfe = dev_get_drvdata(dev);
 	struct vpfe_ccdc *ccdc = &vpfe->ccdc;
+	int ret;
 
 	/* only do full suspend if streaming has started */
 	if (vb2_start_streaming_called(&vpfe->buffer_queue)) {
-		pm_runtime_get_sync(dev);
+		ret = pm_runtime_resume_and_get(dev);
 		vpfe_config_enable(ccdc, 1);
 
 		/* Save VPFE context */
@@ -2541,7 +2548,8 @@ static int vpfe_suspend(struct device *dev)
 		vpfe_config_enable(ccdc, 0);
 
 		/* Disable both master and slave clock */
-		pm_runtime_put_sync(dev);
+		if (ret >= 0)
+			pm_runtime_put_sync(dev);
 	}
 
 	/* Select sleep pin state */
@@ -2583,18 +2591,20 @@ static int vpfe_resume(struct device *dev)
 {
 	struct vpfe_device *vpfe = dev_get_drvdata(dev);
 	struct vpfe_ccdc *ccdc = &vpfe->ccdc;
+	int ret;
 
 	/* only do full resume if streaming has started */
 	if (vb2_start_streaming_called(&vpfe->buffer_queue)) {
 		/* Enable both master and slave clock */
-		pm_runtime_get_sync(dev);
+		ret = pm_runtime_resume_and_get(dev);
 		vpfe_config_enable(ccdc, 1);
 
 		/* Restore VPFE context */
 		vpfe_restore_context(ccdc);
 
 		vpfe_config_enable(ccdc, 0);
-		pm_runtime_put_sync(dev);
+		if (ret >= 0)
+			pm_runtime_put_sync(dev);
 	}
 
 	/* Select default pin state */
-- 
2.30.2