From 27600805e62f800bacf990354632eae4e487d34c Mon Sep 17 00:00:00 2001
From: Yazen Ghannam <yazen.ghannam@amd.com>
Date: Thu, 3 Sep 2026 10:43:25 -0500
Subject: x86/amd_node: Fix PCI device reference counting in amd_smn_init()

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
---
 include/sound/mpu401.h | 123 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)
 create mode 100644 include/sound/mpu401.h

(limited to 'include/sound/mpu401.h')

diff --git a/include/sound/mpu401.h b/include/sound/mpu401.h
new file mode 100644
index 000000000..d4c915a37
--- /dev/null
+++ b/include/sound/mpu401.h
@@ -0,0 +1,123 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __SOUND_MPU401_H
+#define __SOUND_MPU401_H
+
+/*
+ *  Header file for MPU-401 and compatible cards
+ *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
+ */
+
+#include <sound/rawmidi.h>
+#include <linux/interrupt.h>
+
+#define MPU401_HW_MPU401		1	/* native MPU401 */
+#define MPU401_HW_SB			2	/* SoundBlaster MPU-401 UART */
+#define MPU401_HW_ES1688		3	/* AudioDrive ES1688 MPU-401 UART */
+#define MPU401_HW_OPL3SA2		4	/* Yamaha OPL3-SA2 */
+#define MPU401_HW_SONICVIBES		5	/* S3 SonicVibes */
+#define MPU401_HW_CS4232		6	/* CS4232 */
+#define MPU401_HW_ES18XX		7	/* AudioDrive ES18XX MPU-401 UART */
+#define MPU401_HW_FM801			8	/* ForteMedia FM801 */
+#define MPU401_HW_TRID4DWAVE		9	/* Trident 4DWave */
+#define MPU401_HW_AZT2320		10	/* Aztech AZT2320 */
+#define MPU401_HW_ALS100		11	/* Avance Logic ALS100 */
+#define MPU401_HW_ICE1712		12	/* Envy24 */
+#define MPU401_HW_VIA686A		13	/* VIA 82C686A */
+#define MPU401_HW_YMFPCI		14	/* YMF DS-XG PCI */
+#define MPU401_HW_CMIPCI		15	/* CMIPCI MPU-401 UART */
+#define MPU401_HW_ALS4000		16	/* Avance Logic ALS4000 */
+#define MPU401_HW_INTEL8X0		17	/* Intel8x0 driver */
+#define MPU401_HW_PC98II		18	/* Roland PC98II */
+#define MPU401_HW_AUREAL		19	/* Aureal Vortex */
+
+#define MPU401_INFO_INPUT	(1 << 0)	/* input stream */
+#define MPU401_INFO_OUTPUT	(1 << 1)	/* output stream */
+#define MPU401_INFO_INTEGRATED	(1 << 2)	/* integrated h/w port */
+#define MPU401_INFO_MMIO	(1 << 3)	/* MMIO access */
+#define MPU401_INFO_TX_IRQ	(1 << 4)	/* independent TX irq */
+#define MPU401_INFO_IRQ_HOOK	(1 << 5)	/* mpu401 irq handler is called
+						   from driver irq handler */
+#define MPU401_INFO_NO_ACK	(1 << 6)	/* No ACK cmd needed */
+#define MPU401_INFO_USE_TIMER	(1 << 15)	/* internal */
+
+#define MPU401_MODE_BIT_INPUT		0
+#define MPU401_MODE_BIT_OUTPUT		1
+#define MPU401_MODE_BIT_INPUT_TRIGGER	2
+#define MPU401_MODE_BIT_OUTPUT_TRIGGER	3
+
+#define MPU401_MODE_INPUT		(1<<MPU401_MODE_BIT_INPUT)
+#define MPU401_MODE_OUTPUT		(1<<MPU401_MODE_BIT_OUTPUT)
+#define MPU401_MODE_INPUT_TRIGGER	(1<<MPU401_MODE_BIT_INPUT_TRIGGER)
+#define MPU401_MODE_OUTPUT_TRIGGER	(1<<MPU401_MODE_BIT_OUTPUT_TRIGGER)
+
+#define MPU401_MODE_INPUT_TIMER		(1<<0)
+#define MPU401_MODE_OUTPUT_TIMER	(1<<1)
+
+struct snd_mpu401 {
+	struct snd_rawmidi *rmidi;
+
+	unsigned short hardware;	/* MPU401_HW_XXXX */
+	unsigned int info_flags;	/* MPU401_INFO_XXX */
+	unsigned long port;		/* base port of MPU-401 chip */
+	unsigned long cport;		/* port + 1 (usually) */
+	struct resource *res;		/* port resource */
+	int irq;			/* IRQ number of MPU-401 chip */
+
+	unsigned long mode;		/* MPU401_MODE_XXXX */
+	int timer_invoked;
+
+	int (*open_input) (struct snd_mpu401 * mpu);
+	void (*close_input) (struct snd_mpu401 * mpu);
+	int (*open_output) (struct snd_mpu401 * mpu);
+	void (*close_output) (struct snd_mpu401 * mpu);
+	void *private_data;
+
+	struct snd_rawmidi_substream *substream_input;
+	struct snd_rawmidi_substream *substream_output;
+
+	spinlock_t input_lock;
+	spinlock_t output_lock;
+	spinlock_t timer_lock;
+	
+	struct timer_list timer;
+
+	void (*write) (struct snd_mpu401 * mpu, unsigned char data, unsigned long addr);
+	unsigned char (*read) (struct snd_mpu401 *mpu, unsigned long addr);
+};
+
+/* I/O ports */
+
+#define MPU401C(mpu) (mpu)->cport
+#define MPU401D(mpu) (mpu)->port
+
+/*
+ * control register bits
+ */
+/* read MPU401C() */
+#define MPU401_RX_EMPTY		0x80
+#define MPU401_TX_FULL		0x40
+
+/* write MPU401C() */
+#define MPU401_RESET		0xff
+#define MPU401_ENTER_UART	0x3f
+
+/* read MPU401D() */
+#define MPU401_ACK		0xfe
+
+
+/*
+
+ */
+
+irqreturn_t snd_mpu401_uart_interrupt(int irq, void *dev_id);
+irqreturn_t snd_mpu401_uart_interrupt_tx(int irq, void *dev_id);
+
+int snd_mpu401_uart_new(struct snd_card *card,
+			int device,
+			unsigned short hardware,
+			unsigned long port,
+			unsigned int info_flags,
+			int irq,
+			struct snd_rawmidi ** rrawmidi);
+
+#endif /* __SOUND_MPU401_H */
-- 
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