media: pisp_be: Fix pm_runtime underrun in probe

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>

diff --git a/drivers/media/platform/raspberrypi/pisp_be/Kconfig b/drivers/media/platform/raspberrypi/pisp_be/Kconfig
index 46765a2e4c4d1573757ff842f208834216e582cb..a9e51fd94aadc6add70f883bfcea0c9fa91f0c4b 100644 (file)
--- 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

diff --git a/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c b/drivers/media/platform/raspberrypi/pisp_be/pisp_be.c
index 7596ae1f7de6671484d4d351015b234829f642d4..f0a98afefdbd1eb03decad9b57fb50004a2847ea 100644 (file)
--- 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_device *pdev)
        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_device *pdev)
 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 platform_device *pdev)
 
        pispbe_destroy_devices(pispbe);
 
-       pispbe_runtime_suspend(pispbe->dev);
        pm_runtime_dont_use_autosuspend(pispbe->dev);
        pm_runtime_disable(pispbe->dev);
 }