[PATCH v2 2/2] drivers: bus: simple-pm-bus: Add support for probing simple bus only devices

From: Saravana Kannan
Date: Thu Sep 02 2021 - 19:04:54 EST


The OF platform code sets up simple bus only devices (i.e. devices that
won't match with any other driver) to get probed by the simple-pm-bus to
keep fw_devlink from blocking probe() or sync_state() [1] callbacks of
other devices. There's no need to populate the child devices since the
OF platform code would do that anyway, so return early for these simple
bus only devices.

[1] - https://lore.kernel.org/lkml/CAPDyKFo9Bxremkb1dDrr4OcXSpE0keVze94Cm=zrkOVxHHxBmQ@xxxxxxxxxxxxxx/
Signed-off-by: Saravana Kannan <saravanak@xxxxxxxxxx>
Tested-by: Saravana Kannan <saravanak@xxxxxxxxxx>
---
drivers/bus/simple-pm-bus.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/drivers/bus/simple-pm-bus.c b/drivers/bus/simple-pm-bus.c
index 01a3d0cd08ed..91d52021b7f9 100644
--- a/drivers/bus/simple-pm-bus.c
+++ b/drivers/bus/simple-pm-bus.c
@@ -19,6 +19,13 @@ static int simple_pm_bus_probe(struct platform_device *pdev)
const struct of_dev_auxdata *lookup = dev_get_platdata(&pdev->dev);
struct device_node *np = pdev->dev.of_node;

+ /*
+ * These are transparent bus devices (not simple-pm-bus matches) that
+ * get populated automatically. So, don't need to do anything more.
+ */
+ if (pdev->driver_override)
+ return 0;
+
dev_dbg(&pdev->dev, "%s\n", __func__);

pm_runtime_enable(&pdev->dev);
--
2.33.0.153.gba50c8fa24-goog