[PATCH 3/8] interconnect: qcom: icc-rpm: depopulate SMD RPM child NoCs

[Dmitry Baryshkov]

From: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>

qnoc_probe() creates the child NoC devices (the QCM2290 and SM6115
virtual NoCs, the MSM8939 SNoC MM and the MSM8998 MMSS AHB NoC) with
of_platform_populate(), but nothing ever removes them. Unbinding the
parent NoC therefore leaves the children bound, although they live in
the parent's register space and use the parent's regmap, which devres
frees together with the parent. Binding the parent again does not
recreate them either, as their DT nodes are still marked as populated,
so they keep running with the state of the previous parent instance.

Populate the children with devm_of_platform_populate() and depopulate
them at the start of qnoc_remove(), so that they go away before the
provider they depend on. Leaving it to devres alone would only remove
them after qnoc_remove() has already torn the parent provider down.

Fixes: e39bf2972c6e ("interconnect: icc-rpm: Support child NoC device probe")
Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxxxxxxxx>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxxxxxxxx>
---
 drivers/interconnect/qcom/icc-rpm.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/interconnect/qcom/icc-rpm.c b/drivers/interconnect/qcom/icc-rpm.c
index 6f325789a96e..ddc7df31ed33 100644
--- a/drivers/interconnect/qcom/icc-rpm.c
+++ b/drivers/interconnect/qcom/icc-rpm.c
@@ -677,7 +677,7 @@ int qnoc_probe(struct platform_device *pdev)
 
 	/* Populate child NoC devices if any */
 	if (of_get_child_count(dev->of_node) > 0) {
-		ret = of_platform_populate(dev->of_node, NULL, NULL, dev);
+		ret = devm_of_platform_populate(dev);
 		if (ret)
 			goto err_deregister_provider;
 	}
@@ -699,6 +699,7 @@ void qnoc_remove(struct platform_device *pdev)
 {
 	struct qcom_icc_provider *qp = platform_get_drvdata(pdev);
 
+	devm_of_platform_depopulate(&pdev->dev);
 	icc_provider_deregister(&qp->provider);
 	icc_nodes_remove(&qp->provider);
 	clk_disable_unprepare(qp->bus_clk);

-- 
2.47.3