From bce7698e2e6565bb765bd0522337f29f5f312624 Mon Sep 17 00:00:00 2001 From: Haojie Li Date: Tue, 25 Aug 2026 18:08:45 +0800 Subject: drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform device platform_device_register_data() can fail and return an ERR_PTR, but the return value is used without checking, leading to an invalid pointer being stored in ddp_comp[].dev and passed to component_match_add() and mtk_ddp_comp_init(), which could result in a kernel crash. Add an IS_ERR() check to jump to the error handling path on failure. Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195") Cc: stable@vger.kernel.org Signed-off-by: Haojie Li Reviewed-by: CK Hu Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/ Signed-off-by: Chun-Kuang Hu --- drivers/reset/reset-ath79.c | 127 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 127 insertions(+) create mode 100644 drivers/reset/reset-ath79.c (limited to 'drivers/reset/reset-ath79.c') diff --git a/drivers/reset/reset-ath79.c b/drivers/reset/reset-ath79.c new file mode 100644 index 000000000..1a2c0f8a5 --- /dev/null +++ b/drivers/reset/reset-ath79.c @@ -0,0 +1,127 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * AR71xx Reset Controller Driver + * Author: Alban Bedel + * + * Copyright (C) 2015 Alban Bedel + */ + +#include +#include +#include +#include +#include + +struct ath79_reset { + struct reset_controller_dev rcdev; + void __iomem *base; + spinlock_t lock; +}; + +#define FULL_CHIP_RESET 24 + +static int ath79_reset_update(struct reset_controller_dev *rcdev, + unsigned long id, bool assert) +{ + struct ath79_reset *ath79_reset = + container_of(rcdev, struct ath79_reset, rcdev); + unsigned long flags; + u32 val; + + spin_lock_irqsave(&ath79_reset->lock, flags); + val = readl(ath79_reset->base); + if (assert) + val |= BIT(id); + else + val &= ~BIT(id); + writel(val, ath79_reset->base); + spin_unlock_irqrestore(&ath79_reset->lock, flags); + + return 0; +} + +static int ath79_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return ath79_reset_update(rcdev, id, true); +} + +static int ath79_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + return ath79_reset_update(rcdev, id, false); +} + +static int ath79_reset_status(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct ath79_reset *ath79_reset = + container_of(rcdev, struct ath79_reset, rcdev); + u32 val; + + val = readl(ath79_reset->base); + + return !!(val & BIT(id)); +} + +static const struct reset_control_ops ath79_reset_ops = { + .assert = ath79_reset_assert, + .deassert = ath79_reset_deassert, + .status = ath79_reset_status, +}; + +static int ath79_reset_restart_handler(struct sys_off_data *data) +{ + struct ath79_reset *ath79_reset = data->cb_data; + + ath79_reset_assert(&ath79_reset->rcdev, FULL_CHIP_RESET); + + return NOTIFY_DONE; +} + +static int ath79_reset_probe(struct platform_device *pdev) +{ + struct ath79_reset *ath79_reset; + int err; + + ath79_reset = devm_kzalloc(&pdev->dev, + sizeof(*ath79_reset), GFP_KERNEL); + if (!ath79_reset) + return -ENOMEM; + + ath79_reset->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(ath79_reset->base)) + return PTR_ERR(ath79_reset->base); + + spin_lock_init(&ath79_reset->lock); + ath79_reset->rcdev.ops = &ath79_reset_ops; + ath79_reset->rcdev.owner = THIS_MODULE; + ath79_reset->rcdev.of_node = pdev->dev.of_node; + ath79_reset->rcdev.of_reset_n_cells = 1; + ath79_reset->rcdev.nr_resets = 32; + + err = devm_reset_controller_register(&pdev->dev, &ath79_reset->rcdev); + if (err) + return err; + + err = devm_register_restart_handler(&pdev->dev, ath79_reset_restart_handler, ath79_reset); + if (err) + dev_warn(&pdev->dev, "Failed to register restart handler\n"); + + return 0; +} + +static const struct of_device_id ath79_reset_dt_ids[] = { + { .compatible = "qca,ar7100-reset", }, + { }, +}; + +static struct platform_driver ath79_reset_driver = { + .probe = ath79_reset_probe, + .driver = { + .name = "ath79-reset", + .of_match_table = ath79_reset_dt_ids, + .suppress_bind_attrs = true, + }, +}; +builtin_platform_driver(ath79_reset_driver); -- cgit v1.3.1