[PATCH AUTOSEL 5.12 08/80] media: am437x: fix pm_runtime_get_sync() usage count
From: Sasha Levin <sashal@kernel.org>
Date: 2021-07-04 23:07:51
Also in:
linux-media, lkml
Subsystem:
media input infrastructure (v4l/dvb), the rest · Maintainers:
Mauro Carvalho Chehab, Linus Torvalds
From: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
[ Upstream commit c41e02493334985cca1a22efd5ca962ce3abb061 ]
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, avoiding
a potential PM usage counter leak.
While here, ensure that the driver will check if PM runtime
resumed at vpfe_initialize_device().
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/platform/am437x/am437x-vpfe.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/drivers/media/platform/am437x/am437x-vpfe.c b/drivers/media/platform/am437x/am437x-vpfe.c
index 6cdc77dda0e4..1c9cb9e05fdf 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);
@@ -2530,6 +2536,11 @@ static int vpfe_suspend(struct device *dev) /* only do full suspend if streaming has started */ if (vb2_start_streaming_called(&vpfe->buffer_queue)) { + /* + * ignore RPM resume errors here, as it is already too late. + * A check like that should happen earlier, either at + * open() or just before start streaming. + */ pm_runtime_get_sync(dev); vpfe_config_enable(ccdc, 1);
--
2.30.2