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, 115 insertions, 0 deletions

diff --git a/include/sound/sdca_asoc.h b/include/sound/sdca_asoc.h
new file mode 100644
index 000000000..599a72f33
--- /dev/null
+++ b/include/sound/sdca_asoc.h
@@ -0,0 +1,115 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * The MIPI SDCA specification is available for public downloads at
+ * https://www.mipi.org/mipi-sdca-v1-0-download
+ *
+ * Copyright (C) 2025 Cirrus Logic, Inc. and
+ *                    Cirrus Logic International Semiconductor Ltd.
+ */
+
+#ifndef __SDCA_ASOC_H__
+#define __SDCA_ASOC_H__
+
+struct device;
+struct regmap;
+struct sdca_function_data;
+struct sdca_pde_delay;
+struct snd_ctl_elem_value;
+struct snd_kcontrol;
+struct snd_kcontrol_new;
+struct snd_pcm_hw_params;
+struct snd_pcm_substream;
+struct snd_soc_component_driver;
+struct snd_soc_dai;
+struct snd_soc_dai_driver;
+struct snd_soc_dai_ops;
+struct snd_soc_dapm_route;
+struct snd_soc_dapm_widget;
+struct snd_soc_pcm_stream;
+struct sdca_entity;
+
+/* convenient macro to handle the mono volume in 7.8 fixed format representation */
+#define SDCA_SINGLE_Q78_TLV(xname, xreg, xmin, xmax, xstep, tlv_array) \
+{ \
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
+	.name = (xname), \
+	.access = SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_READWRITE, \
+	.tlv.p = (tlv_array), \
+	.info = snd_soc_info_volsw, \
+	.get = sdca_asoc_q78_get_volsw, \
+	.put = sdca_asoc_q78_put_volsw, \
+	.private_value = (unsigned long)&(struct soc_mixer_control) { \
+		.reg = (xreg), .rreg = (xreg), \
+		.min = (xmin), .max = (xmax), \
+		.shift = (xstep), .rshift = (xstep), \
+		.sign_bit = 15 \
+	} \
+}
+
+/* convenient macro for stereo volume in 7.8 fixed format with separate registers for L/R */
+#define SDCA_DOUBLE_Q78_TLV(xname, xreg_l, xreg_r, xmin, xmax, xstep, tlv_array) \
+{ \
+	.iface = SNDRV_CTL_ELEM_IFACE_MIXER, \
+	.name = (xname), \
+	.access = SNDRV_CTL_ELEM_ACCESS_TLV_READ | SNDRV_CTL_ELEM_ACCESS_READWRITE, \
+	.tlv.p = (tlv_array), \
+	.info = snd_soc_info_volsw, \
+	.get = sdca_asoc_q78_get_volsw, \
+	.put = sdca_asoc_q78_put_volsw, \
+	.private_value = (unsigned long)&(struct soc_mixer_control) { \
+		.reg = (xreg_l), .rreg = (xreg_r), \
+		.min = (xmin), .max = (xmax), \
+		.shift = (xstep), .rshift = (xstep), \
+		.sign_bit = 15 \
+	} \
+}
+
+int sdca_asoc_count_component(struct device *dev, struct sdca_function_data *function,
+			      int *num_widgets, int *num_routes, int *num_controls,
+			      int *num_dais);
+
+int sdca_asoc_populate_dapm(struct device *dev, struct sdca_function_data *function,
+			    struct snd_soc_dapm_widget *widgets,
+			    struct snd_soc_dapm_route *routes);
+int sdca_asoc_populate_controls(struct device *dev,
+				struct sdca_function_data *function,
+				struct snd_kcontrol_new *kctl);
+int sdca_asoc_populate_dais(struct device *dev, struct sdca_function_data *function,
+			    struct snd_soc_dai_driver *dais,
+			    const struct snd_soc_dai_ops *ops);
+
+int sdca_asoc_populate_component(struct device *dev,
+				 struct sdca_function_data *function,
+				 struct snd_soc_component_driver *component_drv,
+				 struct snd_soc_dai_driver **dai_drv, int *num_dai_drv,
+				 const struct snd_soc_dai_ops *ops);
+
+int sdca_asoc_populate_rate_format(struct device *dev,
+				struct sdca_function_data *function,
+				struct sdca_entity *entity,
+				struct snd_soc_pcm_stream *stream);
+
+int sdca_asoc_set_constraints(struct device *dev, struct regmap *regmap,
+			      struct sdca_function_data *function,
+			      struct snd_pcm_substream *substream,
+			      struct snd_soc_dai *dai);
+void sdca_asoc_free_constraints(struct snd_pcm_substream *substream,
+				struct snd_soc_dai *dai);
+int sdca_asoc_get_port(struct device *dev, struct regmap *regmap,
+		       struct sdca_function_data *function,
+		       struct snd_soc_dai *dai);
+int sdca_asoc_hw_params(struct device *dev, struct regmap *regmap,
+			struct sdca_function_data *function,
+			struct snd_pcm_substream *substream,
+			struct snd_pcm_hw_params *params,
+			struct snd_soc_dai *dai);
+int sdca_asoc_q78_put_volsw(struct snd_kcontrol *kcontrol,
+			    struct snd_ctl_elem_value *ucontrol);
+int sdca_asoc_q78_get_volsw(struct snd_kcontrol *kcontrol,
+			    struct snd_ctl_elem_value *ucontrol);
+int sdca_asoc_pde_poll_actual_ps(struct regmap *regmap,
+				 int function_id, int entity_id,
+				 int from_ps, int to_ps,
+				 const struct sdca_pde_delay *pde_delays,
+				 int num_delays);
+#endif // __SDCA_ASOC_H__