x86/amd_node: Fix PCI device reference counting in amd_smn_init()grafted

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 <sashiko-bot@kernel.org>
Assisted-by: LLM
Signed-off-by: Yazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Cc: <stable@kernel.org>
Link: https://patch.msgid.link/20260903154325.74343-1-yazen.ghannam@amd.com

1 files changed, 199 insertions, 0 deletions

diff --git a/include/sound/intel-nhlt.h b/include/sound/intel-nhlt.h
new file mode 100644
index 000000000..24dbe1668
--- /dev/null
+++ b/include/sound/intel-nhlt.h
@@ -0,0 +1,199 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *  intel-nhlt.h - Intel HDA Platform NHLT header
+ *
+ *  Copyright (c) 2015-2019 Intel Corporation
+ */
+
+#ifndef __INTEL_NHLT_H__
+#define __INTEL_NHLT_H__
+
+#include <linux/acpi.h>
+
+enum nhlt_link_type {
+	NHLT_LINK_HDA = 0,
+	NHLT_LINK_DSP = 1,
+	NHLT_LINK_DMIC = 2,
+	NHLT_LINK_SSP = 3,
+	NHLT_LINK_INVALID
+};
+
+enum nhlt_device_type {
+	NHLT_DEVICE_BT = 0,
+	NHLT_DEVICE_DMIC = 1,
+	NHLT_DEVICE_I2S = 4,
+	NHLT_DEVICE_INVALID
+};
+
+struct wav_fmt {
+	u16 fmt_tag;
+	u16 channels;
+	u32 samples_per_sec;
+	u32 avg_bytes_per_sec;
+	u16 block_align;
+	u16 bits_per_sample;
+	u16 cb_size;
+} __packed;
+
+struct wav_fmt_ext {
+	struct wav_fmt fmt;
+	union samples {
+		u16 valid_bits_per_sample;
+		u16 samples_per_block;
+		u16 reserved;
+	} sample;
+	u32 channel_mask;
+	u8 sub_fmt[16];
+} __packed;
+
+struct nhlt_specific_cfg {
+	u32 size;
+	u8 caps[];
+} __packed;
+
+struct nhlt_fmt_cfg {
+	struct wav_fmt_ext fmt_ext;
+	struct nhlt_specific_cfg config;
+} __packed;
+
+struct nhlt_fmt {
+	u8 fmt_count;
+	struct nhlt_fmt_cfg fmt_config[];
+} __packed;
+
+struct nhlt_endpoint {
+	u32  length;
+	u8   linktype;
+	u8   instance_id;
+	u16  vendor_id;
+	u16  device_id;
+	u16  revision_id;
+	u32  subsystem_id;
+	u8   device_type;
+	u8   direction;
+	u8   virtual_bus_id;
+	struct nhlt_specific_cfg config;
+} __packed;
+
+struct nhlt_acpi_table {
+	struct acpi_table_header header;
+	u8 endpoint_count;
+	struct nhlt_endpoint desc[];
+} __packed;
+
+struct nhlt_resource_desc  {
+	u32 extra;
+	u16 flags;
+	u64 addr_spc_gra;
+	u64 min_addr;
+	u64 max_addr;
+	u64 addr_trans_offset;
+	u64 length;
+} __packed;
+
+#define MIC_ARRAY_2CH 2
+#define MIC_ARRAY_4CH 4
+
+struct nhlt_device_specific_config {
+	u8 virtual_slot;
+	u8 config_type;
+} __packed;
+
+struct nhlt_dmic_array_config {
+	struct nhlt_device_specific_config device_config;
+	u8 array_type;
+} __packed;
+
+struct nhlt_vendor_dmic_array_config {
+	struct nhlt_dmic_array_config dmic_config;
+	u8 nb_mics;
+	/* TODO add vendor mic config */
+} __packed;
+
+enum {
+	NHLT_CONFIG_TYPE_GENERIC = 0,
+	NHLT_CONFIG_TYPE_MIC_ARRAY = 1
+};
+
+enum {
+	NHLT_MIC_ARRAY_2CH_SMALL = 0xa,
+	NHLT_MIC_ARRAY_2CH_BIG = 0xb,
+	NHLT_MIC_ARRAY_4CH_1ST_GEOM = 0xc,
+	NHLT_MIC_ARRAY_4CH_L_SHAPED = 0xd,
+	NHLT_MIC_ARRAY_4CH_2ND_GEOM = 0xe,
+	NHLT_MIC_ARRAY_VENDOR_DEFINED = 0xf,
+};
+
+#if IS_ENABLED(CONFIG_ACPI) && IS_ENABLED(CONFIG_SND_INTEL_NHLT)
+
+struct nhlt_acpi_table *intel_nhlt_init(struct device *dev);
+
+void intel_nhlt_free(struct nhlt_acpi_table *addr);
+
+int intel_nhlt_get_dmic_geo(struct device *dev, struct nhlt_acpi_table *nhlt);
+
+bool intel_nhlt_has_endpoint_type(struct nhlt_acpi_table *nhlt, u8 link_type);
+
+int intel_nhlt_ssp_endpoint_mask(struct nhlt_acpi_table *nhlt, u8 device_type);
+
+int intel_nhlt_ssp_mclk_mask(struct nhlt_acpi_table *nhlt, int ssp_num);
+
+struct nhlt_specific_cfg *
+intel_nhlt_get_endpoint_blob(struct device *dev, struct nhlt_acpi_table *nhlt,
+			     u32 bus_id, u8 link_type, u8 vbps, u8 bps,
+			     u8 num_ch, u32 rate, u8 dir, u8 dev_type);
+
+int intel_nhlt_ssp_device_type(struct device *dev, struct nhlt_acpi_table *nhlt,
+			       u8 virtual_bus_id);
+
+#else
+
+static inline struct nhlt_acpi_table *intel_nhlt_init(struct device *dev)
+{
+	return NULL;
+}
+
+static inline void intel_nhlt_free(struct nhlt_acpi_table *addr)
+{
+}
+
+static inline int intel_nhlt_get_dmic_geo(struct device *dev,
+					  struct nhlt_acpi_table *nhlt)
+{
+	return 0;
+}
+
+static inline bool intel_nhlt_has_endpoint_type(struct nhlt_acpi_table *nhlt,
+						u8 link_type)
+{
+	return false;
+}
+
+static inline int intel_nhlt_ssp_endpoint_mask(struct nhlt_acpi_table *nhlt, u8 device_type)
+{
+	return 0;
+}
+
+static inline int intel_nhlt_ssp_mclk_mask(struct nhlt_acpi_table *nhlt, int ssp_num)
+{
+	return 0;
+}
+
+static inline struct nhlt_specific_cfg *
+intel_nhlt_get_endpoint_blob(struct device *dev, struct nhlt_acpi_table *nhlt,
+			     u32 bus_id, u8 link_type, u8 vbps, u8 bps,
+			     u8 num_ch, u32 rate, u8 dir, u8 dev_type)
+{
+	return NULL;
+}
+
+static inline int intel_nhlt_ssp_device_type(struct device *dev,
+					     struct nhlt_acpi_table *nhlt,
+					     u8 virtual_bus_id)
+{
+	return -EINVAL;
+}
+
+#endif
+
+#endif