[PATCH v9 1/4] bus: simple-pm-bus: Avoid inconsistencies between probe() and remove()

[Herve Codina]

At probe(), operations done depends on device_has_driver_override().

At remove() a call to device_has_driver_override() is also present to
identify operations that need to be done in order to revert operations
previously done at probe().

Nothing prevents device_has_driver_override() to return a different
value when called at probe() and when called at remove(). Indeed, a user
can set driver_override (or clear it) after the probe() call and before
the remove() call.

In that case, inconsistencies are present between pm_runtime_enable()
called at probe() and pm_runtime_disable() called at remove().

In order to ensure that pm_runtime_disable() is called only if
pm_runtime_enable() has been called at probe(), use the devres version
of pm_runtime_enable().

Reported-by: Sashiko <sashiko-bot@xxxxxxxxxx>
Link: https://lore.kernel.org/all/20260630105701.7D0471F00A3A@xxxxxxxxxxxxxxx/
Fixes: 98e96cf80045 ("drivers: bus: simple-pm-bus: Add support for probing simple bus only devices")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Herve Codina <herve.codina@xxxxxxxxxxx>
---
 drivers/bus/simple-pm-bus.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/bus/simple-pm-bus.c b/drivers/bus/simple-pm-bus.c
index c920bd6fbaaf..4322a778e801 100644
--- a/drivers/bus/simple-pm-bus.c
+++ b/drivers/bus/simple-pm-bus.c
@@ -29,6 +29,7 @@ static int simple_pm_bus_probe(struct platform_device *pdev)
 	struct device_node *np = dev->of_node;
 	const struct of_device_id *match;
 	struct simple_pm_bus *bus;
+	int ret;
 
 	/*
 	 * Allow user to use driver_override to bind this driver to a
@@ -66,7 +67,9 @@ static int simple_pm_bus_probe(struct platform_device *pdev)
 
 	dev_dbg(&pdev->dev, "%s\n", __func__);
 
-	pm_runtime_enable(&pdev->dev);
+	ret = devm_pm_runtime_enable(&pdev->dev);
+	if (ret)
+		return dev_err_probe(&pdev->dev, ret, "failed enable pm_runtime\n");
 
 	if (np)
 		of_platform_populate(np, NULL, lookup, &pdev->dev);
@@ -76,14 +79,7 @@ static int simple_pm_bus_probe(struct platform_device *pdev)
 
 static void simple_pm_bus_remove(struct platform_device *pdev)
 {
-	const void *data = of_device_get_match_data(&pdev->dev);
-
-	if (device_has_driver_override(&pdev->dev) || data)
-		return;
-
 	dev_dbg(&pdev->dev, "%s\n", __func__);
-
-	pm_runtime_disable(&pdev->dev);
 }
 
 static int simple_pm_bus_runtime_suspend(struct device *dev)
-- 
2.56.0