From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001 From: Yazen Ghannam Date: Thu, 3 Sep 2026 10:43:25 -0500 Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init() The local "root" pointer is a temporary variable used during the device search. Therefore, refcount related to the search iterators should be cleaned up after the search is complete. Use the __free() cleanup macro to ensure the refcount is decremented when the temporary pointer goes out of scope. Additionally, increment the refcount when caching a root pointer. This ensures the in-use refcount is separate from the temporary search refcounting. Finally, drop the redundant "root = NULL" before the second search loop. The pci_get_class() iterator always decrements the refcount of its "from" argument, so the first loop can only fall through with "root" already NULL. Fixes: 0a4b61d9c2e4 ("x86/amd_node: Fix AMD root device caching") Closes: https://sashiko.dev/#/patchset/20260806160159.230453-1-jason.andryuk%40amd.com Reported-by: Sashiko Assisted-by: LLM Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov (AMD) Reviewed-by: Mario Limonciello (AMD) Cc: Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com --- drivers/bus/tegra-aconnect.c | 116 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) create mode 100644 drivers/bus/tegra-aconnect.c (limited to 'drivers/bus/tegra-aconnect.c') diff --git a/drivers/bus/tegra-aconnect.c b/drivers/bus/tegra-aconnect.c new file mode 100644 index 000000000..9b2b22733 --- /dev/null +++ b/drivers/bus/tegra-aconnect.c @@ -0,0 +1,116 @@ +/* + * Tegra ACONNECT Bus Driver + * + * Copyright (C) 2016, NVIDIA CORPORATION. All rights reserved. + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ + +#include +#include +#include +#include +#include + +struct tegra_aconnect { + struct clk *ape_clk; + struct clk *apb2ape_clk; +}; + +static int tegra_aconnect_probe(struct platform_device *pdev) +{ + struct tegra_aconnect *aconnect; + + if (!pdev->dev.of_node) + return -EINVAL; + + aconnect = devm_kzalloc(&pdev->dev, sizeof(struct tegra_aconnect), + GFP_KERNEL); + if (!aconnect) + return -ENOMEM; + + aconnect->ape_clk = devm_clk_get(&pdev->dev, "ape"); + if (IS_ERR(aconnect->ape_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(aconnect->ape_clk), + "can't retrieve ape clock\n"); + + aconnect->apb2ape_clk = devm_clk_get(&pdev->dev, "apb2ape"); + if (IS_ERR(aconnect->apb2ape_clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(aconnect->apb2ape_clk), + "can't retrieve apb2ape clock\n"); + + dev_set_drvdata(&pdev->dev, aconnect); + pm_runtime_enable(&pdev->dev); + + of_platform_populate(pdev->dev.of_node, NULL, NULL, &pdev->dev); + + dev_info(&pdev->dev, "Tegra ACONNECT bus registered\n"); + + return 0; +} + +static void tegra_aconnect_remove(struct platform_device *pdev) +{ + pm_runtime_disable(&pdev->dev); +} + +static int tegra_aconnect_runtime_resume(struct device *dev) +{ + struct tegra_aconnect *aconnect = dev_get_drvdata(dev); + int ret; + + ret = clk_prepare_enable(aconnect->ape_clk); + if (ret) { + dev_err(dev, "ape clk_enable failed: %d\n", ret); + return ret; + } + + ret = clk_prepare_enable(aconnect->apb2ape_clk); + if (ret) { + clk_disable_unprepare(aconnect->ape_clk); + dev_err(dev, "apb2ape clk_enable failed: %d\n", ret); + return ret; + } + + return 0; +} + +static int tegra_aconnect_runtime_suspend(struct device *dev) +{ + struct tegra_aconnect *aconnect = dev_get_drvdata(dev); + + clk_disable_unprepare(aconnect->ape_clk); + clk_disable_unprepare(aconnect->apb2ape_clk); + + return 0; +} + +static const struct dev_pm_ops tegra_aconnect_pm_ops = { + SET_RUNTIME_PM_OPS(tegra_aconnect_runtime_suspend, + tegra_aconnect_runtime_resume, NULL) + SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) +}; + +static const struct of_device_id tegra_aconnect_of_match[] = { + { .compatible = "nvidia,tegra210-aconnect", }, + { } +}; +MODULE_DEVICE_TABLE(of, tegra_aconnect_of_match); + +static struct platform_driver tegra_aconnect_driver = { + .probe = tegra_aconnect_probe, + .remove = tegra_aconnect_remove, + .driver = { + .name = "tegra-aconnect", + .of_match_table = tegra_aconnect_of_match, + .pm = &tegra_aconnect_pm_ops, + }, +}; +module_platform_driver(tegra_aconnect_driver); + +MODULE_DESCRIPTION("NVIDIA Tegra ACONNECT Bus Driver"); +MODULE_AUTHOR("Jon Hunter "); +MODULE_LICENSE("GPL v2"); -- cgit v1.3.1