memory: tegra30-emc: fix interconnect registration race

commit 9db481c909dd6312ccfbdc7e343b50e41c727483 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: d5ef16ba5fbe ("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/20230306075651.2449-21-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/tegra30-emc.c b/drivers/memory/tegra/tegra30-emc.c
index 9ba2a9e5316bd0efe165bc97f85d0ea6d1a9cd49..1ea3792beb86d2b81ab26be7611ac3ce2d0d25a6 100644 (file)
--- a/drivers/memory/tegra/tegra30-emc.c
+++ b/drivers/memory/tegra/tegra30-emc.c
@@ -1546,15 +1546,13 @@ 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";
@@ -1575,12 +1573,14 @@ 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);