6.16-stable review patch. If anyone has any objections, please let me know.
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From: Jacopo Mondi jacopo.mondi@ideasonboard.com
commit e9bb2eacc7222ff8210903eb3b7d56709cc53228 upstream.
During the probe() routine, the PiSP BE driver needs to power up the interface in order to identify and initialize the hardware.
The driver resumes the interface by calling the pispbe_runtime_resume() function directly, without going through the pm_runtime helpers, but later suspends it by calling pm_runtime_put_autosuspend().
This causes a PM usage count imbalance at probe time, notified by the runtime_pm framework with the below message in the system log:
pispbe 1000880000.pisp_be: Runtime PM usage count underflow!
Fix this by resuming the interface using the pm runtime helpers instead of calling the resume function directly and use the pm_runtime framework in the probe() error path. While at it, remove manual suspend of the interface in the remove() function. The driver cannot be unloaded if in use, so simply disable runtime pm.
To simplify the implementation, make the driver depend on PM as the RPI5 platform where the ISP is integrated in uses the PM framework by default.
Fixes: 12187bd5d4f8 ("media: raspberrypi: Add support for PiSP BE") Cc: stable@vger.kernel.org Tested-by: Naushir Patuck naush@raspberrypi.com Reviewed-by: Naushir Patuck naush@raspberrypi.com Reviewed-by: Laurent Pinchart laurent.pinchart@ideasonboard.com Signed-off-by: Jacopo Mondi jacopo.mondi@ideasonboard.com Signed-off-by: Hans Verkuil hverkuil@xs4all.nl Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/media/platform/raspberrypi/pisp_be/Kconfig | 1 + drivers/media/platform/raspberrypi/pisp_be/pisp_be.c | 5 ++--- 2 files changed, 3 insertions(+), 3 deletions(-)
--- a/drivers/media/platform/raspberrypi/pisp_be/Kconfig +++ b/drivers/media/platform/raspberrypi/pisp_be/Kconfig @@ -3,6 +3,7 @@ config VIDEO_RASPBERRYPI_PISP_BE depends on V4L_PLATFORM_DRIVERS depends on VIDEO_DEV depends on ARCH_BCM2835 || COMPILE_TEST + depends on PM select VIDEO_V4L2_SUBDEV_API select MEDIA_CONTROLLER select VIDEOBUF2_DMA_CONTIG --- a/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c +++ b/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c @@ -1726,7 +1726,7 @@ static int pispbe_probe(struct platform_ pm_runtime_use_autosuspend(pispbe->dev); pm_runtime_enable(pispbe->dev);
- ret = pispbe_runtime_resume(pispbe->dev); + ret = pm_runtime_resume_and_get(pispbe->dev); if (ret) goto pm_runtime_disable_err;
@@ -1748,7 +1748,7 @@ static int pispbe_probe(struct platform_ disable_devs_err: pispbe_destroy_devices(pispbe); pm_runtime_suspend_err: - pispbe_runtime_suspend(pispbe->dev); + pm_runtime_put(pispbe->dev); pm_runtime_disable_err: pm_runtime_dont_use_autosuspend(pispbe->dev); pm_runtime_disable(pispbe->dev); @@ -1762,7 +1762,6 @@ static void pispbe_remove(struct platfor
pispbe_destroy_devices(pispbe);
- pispbe_runtime_suspend(pispbe->dev); pm_runtime_dont_use_autosuspend(pispbe->dev); pm_runtime_disable(pispbe->dev); }