interconnect: qcom: osm-l3: fix registration race

The current interconnect provider registration interface is inherently
racy as nodes are not added until the after adding the provider. This
can specifically cause racing DT lookups to fail:

	of_icc_xlate_onecell: invalid index 0
	cpu cpu0: error -EINVAL: error finding src node
	cpu cpu0: dev_pm_opp_of_find_icc_paths: Unable to get path0: -22
	qcom-cpufreq-hw: probe of 18591000.cpufreq failed with error -22

Switch to using the new API where the provider is not registered until
after it has been fully initialised.

Fixes: 5bc9900addaf ("interconnect: qcom: Add OSM L3 interconnect provider support")
Cc: stable@vger.kernel.org      # 5.7
Reviewed-by: Konrad Dybcio <konrad.dybcio@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-6-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>

diff --git a/drivers/interconnect/qcom/osm-l3.c b/drivers/interconnect/qcom/osm-l3.c
index 1bc01ff..1bafb54 100644 (file)
--- a/drivers/interconnect/qcom/osm-l3.c
+++ b/drivers/interconnect/qcom/osm-l3.c
@@ -158,8 +158,8 @@ static int qcom_osm_l3_remove(struct platform_device *pdev)
 {
        struct qcom_osm_l3_icc_provider *qp = platform_get_drvdata(pdev);
 
+       icc_provider_deregister(&qp->provider);
        icc_nodes_remove(&qp->provider);
-       icc_provider_del(&qp->provider);
 
        return 0;
 }
@@ -245,14 +245,9 @@ static int qcom_osm_l3_probe(struct platform_device *pdev)
        provider->set = qcom_osm_l3_set;
        provider->aggregate = icc_std_aggregate;
        provider->xlate = of_icc_xlate_onecell;
-       INIT_LIST_HEAD(&provider->nodes);
        provider->data = data;
 
-       ret = icc_provider_add(provider);
-       if (ret) {
-               dev_err(&pdev->dev, "error adding interconnect provider\n");
-               return ret;
-       }
+       icc_provider_init(provider);
 
        for (i = 0; i < num_nodes; i++) {
                size_t j;
@@ -275,12 +270,15 @@ static int qcom_osm_l3_probe(struct platform_device *pdev)
        }
        data->num_nodes = num_nodes;
 
+       ret = icc_provider_register(provider);
+       if (ret)
+               goto err;
+
        platform_set_drvdata(pdev, qp);
 
        return 0;
 err:
        icc_nodes_remove(provider);
-       icc_provider_del(provider);
 
        return ret;
 }