drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform devicegrafted

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 <lihaojie@kylinos.cn>
Reviewed-by: CK Hu <ck.hu@mediatek.com>
Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>

3 files changed, 81 insertions, 0 deletions

diff --git a/drivers/reset/tegra/Kconfig b/drivers/reset/tegra/Kconfig
new file mode 100644
index 000000000..4a2d26d12
--- /dev/null
+++ b/drivers/reset/tegra/Kconfig
@@ -0,0 +1,4 @@
+# SPDX-License-Identifier: GPL-2.0-only
+config RESET_TEGRA_BPMP
+	bool "Tegra BPMP Reset Driver" if COMPILE_TEST
+	default TEGRA_BPMP
diff --git a/drivers/reset/tegra/Makefile b/drivers/reset/tegra/Makefile
new file mode 100644
index 000000000..eccba896a
--- /dev/null
+++ b/drivers/reset/tegra/Makefile
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+obj-$(CONFIG_RESET_TEGRA_BPMP) += reset-bpmp.o
diff --git a/drivers/reset/tegra/reset-bpmp.c b/drivers/reset/tegra/reset-bpmp.c
new file mode 100644
index 000000000..4c5bba52b
--- /dev/null
+++ b/drivers/reset/tegra/reset-bpmp.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2016 NVIDIA Corporation
+ */
+
+#include <linux/reset-controller.h>
+
+#include <soc/tegra/bpmp.h>
+#include <soc/tegra/bpmp-abi.h>
+
+static struct tegra_bpmp *to_tegra_bpmp(struct reset_controller_dev *rstc)
+{
+	return container_of(rstc, struct tegra_bpmp, rstc);
+}
+
+static int tegra_bpmp_reset_common(struct reset_controller_dev *rstc,
+				   enum mrq_reset_commands command,
+				   unsigned int id)
+{
+	struct tegra_bpmp *bpmp = to_tegra_bpmp(rstc);
+	struct mrq_reset_request request;
+	struct tegra_bpmp_message msg;
+	int err;
+
+	memset(&request, 0, sizeof(request));
+	request.cmd = command;
+	request.reset_id = id;
+
+	memset(&msg, 0, sizeof(msg));
+	msg.mrq = MRQ_RESET;
+	msg.tx.data = &request;
+	msg.tx.size = sizeof(request);
+
+	err = tegra_bpmp_transfer(bpmp, &msg);
+	if (err)
+		return err;
+	if (msg.rx.ret)
+		return -EINVAL;
+
+	return 0;
+}
+
+static int tegra_bpmp_reset_module(struct reset_controller_dev *rstc,
+				   unsigned long id)
+{
+	return tegra_bpmp_reset_common(rstc, CMD_RESET_MODULE, id);
+}
+
+static int tegra_bpmp_reset_assert(struct reset_controller_dev *rstc,
+				   unsigned long id)
+{
+	return tegra_bpmp_reset_common(rstc, CMD_RESET_ASSERT, id);
+}
+
+static int tegra_bpmp_reset_deassert(struct reset_controller_dev *rstc,
+				     unsigned long id)
+{
+	return tegra_bpmp_reset_common(rstc, CMD_RESET_DEASSERT, id);
+}
+
+static const struct reset_control_ops tegra_bpmp_reset_ops = {
+	.reset = tegra_bpmp_reset_module,
+	.assert = tegra_bpmp_reset_assert,
+	.deassert = tegra_bpmp_reset_deassert,
+};
+
+int tegra_bpmp_init_resets(struct tegra_bpmp *bpmp)
+{
+	bpmp->rstc.ops = &tegra_bpmp_reset_ops;
+	bpmp->rstc.owner = THIS_MODULE;
+	bpmp->rstc.of_node = bpmp->dev->of_node;
+	bpmp->rstc.nr_resets = bpmp->soc->num_resets;
+
+	return devm_reset_controller_register(bpmp->dev, &bpmp->rstc);
+}