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, 138 insertions, 0 deletions

diff --git a/include/sound/soc-usb.h b/include/sound/soc-usb.h
new file mode 100644
index 000000000..124acb193
--- /dev/null
+++ b/include/sound/soc-usb.h
@@ -0,0 +1,138 @@
+/* SPDX-License-Identifier: GPL-2.0
+ *
+ * Copyright (c) 2022-2025 Qualcomm Innovation Center, Inc. All rights reserved.
+ */
+
+#ifndef __LINUX_SND_SOC_USB_H
+#define __LINUX_SND_SOC_USB_H
+
+#include <sound/soc.h>
+
+enum snd_soc_usb_kctl {
+	SND_SOC_USB_KCTL_CARD_ROUTE,
+	SND_SOC_USB_KCTL_PCM_ROUTE,
+};
+
+/**
+ * struct snd_soc_usb_device - SoC USB representation of a USB sound device
+ * @card_idx: sound card index associated with USB device
+ * @chip_idx: USB sound chip array index
+ * @cpcm_idx: capture PCM index array associated with USB device
+ * @ppcm_idx: playback PCM index array associated with USB device
+ * @num_capture: number of capture streams
+ * @num_playback: number of playback streams
+ * @list: list head for SoC USB devices
+ **/
+struct snd_soc_usb_device {
+	int card_idx;
+	int chip_idx;
+
+	/* PCM index arrays */
+	unsigned int *cpcm_idx; /* TODO: capture path is not tested yet */
+	unsigned int *ppcm_idx;
+	int num_capture; /* TODO: capture path is not tested yet */
+	int num_playback;
+
+	struct list_head list;
+};
+
+/**
+ * struct snd_soc_usb - representation of a SoC USB backend entity
+ * @list: list head for SND SOC struct list
+ * @component: reference to ASoC component
+ * @connection_status_cb: callback to notify connection events
+ * @update_offload_route_info: callback to fetch mapped ASoC card and pcm
+ *			       device pair.  This is unrelated to the concept
+ *			       of DAPM route.  The "route" argument carries
+ *			       an array used for a kcontrol output for either
+ *			       the card or pcm index.  "path" determines the
+ *			       which entry to look for. (ie mapped card or pcm)
+ * @priv_data: driver data
+ **/
+struct snd_soc_usb {
+	struct list_head list;
+	struct snd_soc_component *component;
+	int (*connection_status_cb)(struct snd_soc_usb *usb,
+				    struct snd_soc_usb_device *sdev,
+				    bool connected);
+	int (*update_offload_route_info)(struct snd_soc_component *component,
+					 int card, int pcm, int direction,
+					 enum snd_soc_usb_kctl path,
+					 long *route);
+	void *priv_data;
+};
+
+#if IS_ENABLED(CONFIG_SND_SOC_USB)
+int snd_soc_usb_find_supported_format(int card_idx,
+				      struct snd_pcm_hw_params *params,
+				      int direction);
+
+int snd_soc_usb_connect(struct device *usbdev, struct snd_soc_usb_device *sdev);
+int snd_soc_usb_disconnect(struct device *usbdev, struct snd_soc_usb_device *sdev);
+void *snd_soc_usb_find_priv_data(struct device *usbdev);
+
+int snd_soc_usb_setup_offload_jack(struct snd_soc_component *component,
+				   struct snd_soc_jack *jack);
+int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm,
+				     int direction, enum snd_soc_usb_kctl path,
+				     long *route);
+
+struct snd_soc_usb *snd_soc_usb_allocate_port(struct snd_soc_component *component,
+					      void *data);
+void snd_soc_usb_free_port(struct snd_soc_usb *usb);
+void snd_soc_usb_add_port(struct snd_soc_usb *usb);
+void snd_soc_usb_remove_port(struct snd_soc_usb *usb);
+#else
+static inline int
+snd_soc_usb_find_supported_format(int card_idx, struct snd_pcm_hw_params *params,
+				  int direction)
+{
+	return -EINVAL;
+}
+
+static inline int snd_soc_usb_connect(struct device *usbdev,
+				      struct snd_soc_usb_device *sdev)
+{
+	return -ENODEV;
+}
+
+static inline int snd_soc_usb_disconnect(struct device *usbdev,
+					 struct snd_soc_usb_device *sdev)
+{
+	return -EINVAL;
+}
+
+static inline void *snd_soc_usb_find_priv_data(struct device *usbdev)
+{
+	return NULL;
+}
+
+static inline int snd_soc_usb_setup_offload_jack(struct snd_soc_component *component,
+						 struct snd_soc_jack *jack)
+{
+	return 0;
+}
+
+static int snd_soc_usb_update_offload_route(struct device *dev, int card, int pcm,
+					    int direction, enum snd_soc_usb_kctl path,
+					    long *route)
+{
+	return -ENODEV;
+}
+
+static inline struct snd_soc_usb *
+snd_soc_usb_allocate_port(struct snd_soc_component *component, void *data)
+{
+	return ERR_PTR(-ENOMEM);
+}
+
+static inline void snd_soc_usb_free_port(struct snd_soc_usb *usb)
+{ }
+
+static inline void snd_soc_usb_add_port(struct snd_soc_usb *usb)
+{ }
+
+static inline void snd_soc_usb_remove_port(struct snd_soc_usb *usb)
+{ }
+#endif /* IS_ENABLED(CONFIG_SND_SOC_USB) */
+#endif /*__LINUX_SND_SOC_USB_H */