memory: tegra20-emc: fix interconnect registration race

commit 38b2e362c7c78cdcaf9f9b6a12a336e2ab3cda46 upstream.

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.

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

Fixes: a75551786b7b ("memory: tegra20: Support interconnect framework")
Cc: stable@vger.kernel.org      # 5.11
Cc: Dmitry Osipenko <digetx@gmail.com>
Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
Link: https://lore.kernel.org/r/20230306075651.2449-20-johan+linaro@kernel.org
Signed-off-by: Georgi Djakov <djakov@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/memory/tegra/tegra20-emc.c b/drivers/memory/tegra/tegra20-emc.c
index 25ba3c5e4ad6a69de298da1e658d822a6b3af631..d1f01f80dcbdf54a3926206e8452d5bc22057dc6 100644 (file)
--- a/drivers/memory/tegra/tegra20-emc.c
+++ b/drivers/memory/tegra/tegra20-emc.c
@@ -1034,15 +1034,13 @@ static int tegra_emc_interconnect_init(struct tegra_emc *emc)
        emc->provider.aggregate = soc->icc_ops->aggregate;
        emc->provider.xlate_extended = emc_of_icc_xlate_extended;
 
-       err = icc_provider_add(&emc->provider);
-       if (err)
-               goto err_msg;
+       icc_provider_init(&emc->provider);
 
        /* create External Memory Controller node */
        node = icc_node_create(TEGRA_ICC_EMC);
        if (IS_ERR(node)) {
                err = PTR_ERR(node);
-               goto del_provider;
+               goto err_msg;
        }
 
        node->name = "External Memory Controller";
@@ -1063,12 +1061,14 @@ static int tegra_emc_interconnect_init(struct tegra_emc *emc)
        node->name = "External Memory (DRAM)";
        icc_node_add(node, &emc->provider);
 
+       err = icc_provider_register(&emc->provider);
+       if (err)
+               goto remove_nodes;
+
        return 0;
 
 remove_nodes:
        icc_nodes_remove(&emc->provider);
-del_provider:
-       icc_provider_del(&emc->provider);
 err_msg:
        dev_err(emc->dev, "failed to initialize ICC: %d\n", err);