memory: tegra30-emc: fix interconnect registration race

BugLink: https://bugs.launchpad.net/bugs/2016876
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>
Signed-off-by: Paolo Pisati <paolo.pisati@canonical.com>

diff --git a/drivers/memory/tegra/tegra30-emc.c b/drivers/memory/tegra/tegra30-emc.c
index 77706e9bc5433917712a5c52e68f80134b7fd322..c91e9b7e2e019cf4af40fb0e5253f55455e984c1 100644 (file)
--- a/drivers/memory/tegra/tegra30-emc.c
+++ b/drivers/memory/tegra/tegra30-emc.c
@@ -1533,15 +1533,13 @@ 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";
@@ -1562,12 +1560,14 @@ 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);