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, 242 insertions, 0 deletions

diff --git a/include/sound/cs8403.h b/include/sound/cs8403.h
new file mode 100644
index 000000000..c27f77639
--- /dev/null
+++ b/include/sound/cs8403.h
@@ -0,0 +1,242 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef __SOUND_CS8403_H
+#define __SOUND_CS8403_H
+
+/*
+ *  Routines for Cirrus Logic CS8403/CS8404A IEC958 (S/PDIF) Transmitter
+ *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>,
+ *		     Takashi Iwai <tiwai@suse.de>
+ */
+
+#ifdef SND_CS8403
+
+#ifndef SND_CS8403_DECL
+#define SND_CS8403_DECL static
+#endif
+#ifndef SND_CS8403_DECODE
+#define SND_CS8403_DECODE snd_cs8403_decode_spdif_bits
+#endif
+#ifndef SND_CS8403_ENCODE
+#define SND_CS8403_ENCODE snd_cs8403_encode_spdif_bits
+#endif
+
+
+SND_CS8403_DECL void SND_CS8403_DECODE(struct snd_aes_iec958 *diga, unsigned char bits)
+{
+	if (bits & 0x01) {	/* consumer */
+		if (!(bits & 0x02))
+			diga->status[0] |= IEC958_AES0_NONAUDIO;
+		if (!(bits & 0x08))
+			diga->status[0] |= IEC958_AES0_CON_NOT_COPYRIGHT;
+		switch (bits & 0x10) {
+		case 0x10: diga->status[0] |= IEC958_AES0_CON_EMPHASIS_NONE; break;
+		case 0x00: diga->status[0] |= IEC958_AES0_CON_EMPHASIS_5015; break;
+		}
+		if (!(bits & 0x80))
+			diga->status[1] |= IEC958_AES1_CON_ORIGINAL;
+		switch (bits & 0x60) {
+		case 0x00: diga->status[1] |= IEC958_AES1_CON_MAGNETIC_ID; break;
+		case 0x20: diga->status[1] |= IEC958_AES1_CON_DIGDIGCONV_ID; break;
+		case 0x40: diga->status[1] |= IEC958_AES1_CON_LASEROPT_ID; break;
+		case 0x60: diga->status[1] |= IEC958_AES1_CON_GENERAL; break;
+		}
+		switch (bits & 0x06) {
+		case 0x00: diga->status[3] |= IEC958_AES3_CON_FS_44100; break;
+		case 0x02: diga->status[3] |= IEC958_AES3_CON_FS_48000; break;
+		case 0x04: diga->status[3] |= IEC958_AES3_CON_FS_32000; break;
+		}
+	} else {
+		diga->status[0] = IEC958_AES0_PROFESSIONAL;
+		switch (bits & 0x18) {
+		case 0x00: diga->status[0] |= IEC958_AES0_PRO_FS_32000; break;
+		case 0x10: diga->status[0] |= IEC958_AES0_PRO_FS_44100; break;
+		case 0x08: diga->status[0] |= IEC958_AES0_PRO_FS_48000; break;
+		case 0x18: diga->status[0] |= IEC958_AES0_PRO_FS_NOTID; break;
+		}
+		switch (bits & 0x60) {
+		case 0x20: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_NONE; break;
+		case 0x40: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_5015; break;
+		case 0x00: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_CCITT; break;
+		case 0x60: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_NOTID; break;
+		}
+		if (bits & 0x80)
+			diga->status[1] |= IEC958_AES1_PRO_MODE_STEREOPHONIC;
+	}
+}
+
+SND_CS8403_DECL unsigned char SND_CS8403_ENCODE(struct snd_aes_iec958 *diga)
+{
+	unsigned char bits;
+
+	if (!(diga->status[0] & IEC958_AES0_PROFESSIONAL)) {
+		bits = 0x01;	/* consumer mode */
+		if (diga->status[0] & IEC958_AES0_NONAUDIO)
+			bits &= ~0x02;
+		else
+			bits |= 0x02;
+		if (diga->status[0] & IEC958_AES0_CON_NOT_COPYRIGHT)
+			bits &= ~0x08;
+		else
+			bits |= 0x08;
+		switch (diga->status[0] & IEC958_AES0_CON_EMPHASIS) {
+		default:
+		case IEC958_AES0_CON_EMPHASIS_NONE: bits |= 0x10; break;
+		case IEC958_AES0_CON_EMPHASIS_5015: bits |= 0x00; break;
+		}
+		if (diga->status[1] & IEC958_AES1_CON_ORIGINAL)
+			bits &= ~0x80;
+		else
+			bits |= 0x80;
+		if ((diga->status[1] & IEC958_AES1_CON_CATEGORY) == IEC958_AES1_CON_GENERAL)
+			bits |= 0x60;
+		else {
+			switch(diga->status[1] & IEC958_AES1_CON_MAGNETIC_MASK) {
+			case IEC958_AES1_CON_MAGNETIC_ID:
+				bits |= 0x00; break;
+			case IEC958_AES1_CON_DIGDIGCONV_ID:
+				bits |= 0x20; break;
+			default:
+			case IEC958_AES1_CON_LASEROPT_ID:
+				bits |= 0x40; break;
+			}
+		}
+		switch (diga->status[3] & IEC958_AES3_CON_FS) {
+		default:
+		case IEC958_AES3_CON_FS_44100: bits |= 0x00; break;
+		case IEC958_AES3_CON_FS_48000: bits |= 0x02; break;
+		case IEC958_AES3_CON_FS_32000: bits |= 0x04; break;
+		}
+	} else {
+		bits = 0x00;	/* professional mode */
+		if (diga->status[0] & IEC958_AES0_NONAUDIO)
+			bits &= ~0x02;
+		else
+			bits |= 0x02;
+		/* CHECKME: I'm not sure about the bit order in val here */
+		switch (diga->status[0] & IEC958_AES0_PRO_FS) {
+		case IEC958_AES0_PRO_FS_32000:	bits |= 0x00; break;
+		case IEC958_AES0_PRO_FS_44100:	bits |= 0x10; break;	/* 44.1kHz */
+		case IEC958_AES0_PRO_FS_48000:	bits |= 0x08; break;	/* 48kHz */
+		default:
+		case IEC958_AES0_PRO_FS_NOTID: bits |= 0x18; break;
+		}
+		switch (diga->status[0] & IEC958_AES0_PRO_EMPHASIS) {
+		case IEC958_AES0_PRO_EMPHASIS_NONE: bits |= 0x20; break;
+		case IEC958_AES0_PRO_EMPHASIS_5015: bits |= 0x40; break;
+		case IEC958_AES0_PRO_EMPHASIS_CCITT: bits |= 0x00; break;
+		default:
+		case IEC958_AES0_PRO_EMPHASIS_NOTID: bits |= 0x60; break;
+		}
+		switch (diga->status[1] & IEC958_AES1_PRO_MODE) {
+		case IEC958_AES1_PRO_MODE_TWO:
+		case IEC958_AES1_PRO_MODE_STEREOPHONIC: bits |= 0x00; break;
+		default: bits |= 0x80; break;
+		}
+	}
+	return bits;
+}
+
+#endif /* SND_CS8403 */
+
+#ifdef SND_CS8404
+
+#ifndef SND_CS8404_DECL
+#define SND_CS8404_DECL static
+#endif
+#ifndef SND_CS8404_DECODE
+#define SND_CS8404_DECODE snd_cs8404_decode_spdif_bits
+#endif
+#ifndef SND_CS8404_ENCODE
+#define SND_CS8404_ENCODE snd_cs8404_encode_spdif_bits
+#endif
+
+
+SND_CS8404_DECL void SND_CS8404_DECODE(struct snd_aes_iec958 *diga, unsigned char bits)
+{
+	if (bits & 0x10) {	/* consumer */
+		if (!(bits & 0x20))
+			diga->status[0] |= IEC958_AES0_CON_NOT_COPYRIGHT;
+		if (!(bits & 0x40))
+			diga->status[0] |= IEC958_AES0_CON_EMPHASIS_5015;
+		if (!(bits & 0x80))
+			diga->status[1] |= IEC958_AES1_CON_ORIGINAL;
+		switch (bits & 0x03) {
+		case 0x00: diga->status[1] |= IEC958_AES1_CON_DAT; break;
+		case 0x03: diga->status[1] |= IEC958_AES1_CON_GENERAL; break;
+		}
+		switch (bits & 0x06) {
+		case 0x02: diga->status[3] |= IEC958_AES3_CON_FS_32000; break;
+		case 0x04: diga->status[3] |= IEC958_AES3_CON_FS_48000; break;
+		case 0x06: diga->status[3] |= IEC958_AES3_CON_FS_44100; break;
+		}
+	} else {
+		diga->status[0] = IEC958_AES0_PROFESSIONAL;
+		if (!(bits & 0x04))
+			diga->status[0] |= IEC958_AES0_NONAUDIO;
+		switch (bits & 0x60) {
+		case 0x00: diga->status[0] |= IEC958_AES0_PRO_FS_32000; break;
+		case 0x40: diga->status[0] |= IEC958_AES0_PRO_FS_44100; break;
+		case 0x20: diga->status[0] |= IEC958_AES0_PRO_FS_48000; break;
+		case 0x60: diga->status[0] |= IEC958_AES0_PRO_FS_NOTID; break;
+		}
+		switch (bits & 0x03) {
+		case 0x02: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_NONE; break;
+		case 0x01: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_5015; break;
+		case 0x00: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_CCITT; break;
+		case 0x03: diga->status[0] |= IEC958_AES0_PRO_EMPHASIS_NOTID; break;
+		}
+		if (!(bits & 0x80))
+			diga->status[1] |= IEC958_AES1_PRO_MODE_STEREOPHONIC;
+	}
+}
+
+SND_CS8404_DECL unsigned char SND_CS8404_ENCODE(struct snd_aes_iec958 *diga)
+{
+	unsigned char bits;
+
+	if (!(diga->status[0] & IEC958_AES0_PROFESSIONAL)) {
+		bits = 0x10;	/* consumer mode */
+		if (!(diga->status[0] & IEC958_AES0_CON_NOT_COPYRIGHT))
+			bits |= 0x20;
+		if ((diga->status[0] & IEC958_AES0_CON_EMPHASIS) == IEC958_AES0_CON_EMPHASIS_NONE)
+			bits |= 0x40;
+		if (!(diga->status[1] & IEC958_AES1_CON_ORIGINAL))
+			bits |= 0x80;
+		if ((diga->status[1] & IEC958_AES1_CON_CATEGORY) == IEC958_AES1_CON_GENERAL)
+			bits |= 0x03;
+		switch (diga->status[3] & IEC958_AES3_CON_FS) {
+		default:
+		case IEC958_AES3_CON_FS_44100: bits |= 0x06; break;
+		case IEC958_AES3_CON_FS_48000: bits |= 0x04; break;
+		case IEC958_AES3_CON_FS_32000: bits |= 0x02; break;
+		}
+	} else {
+		bits = 0x00;	/* professional mode */
+		if (!(diga->status[0] & IEC958_AES0_NONAUDIO))
+			bits |= 0x04;
+		switch (diga->status[0] & IEC958_AES0_PRO_FS) {
+		case IEC958_AES0_PRO_FS_32000:	bits |= 0x00; break;
+		case IEC958_AES0_PRO_FS_44100:	bits |= 0x40; break;	/* 44.1kHz */
+		case IEC958_AES0_PRO_FS_48000:	bits |= 0x20; break;	/* 48kHz */
+		default:
+		case IEC958_AES0_PRO_FS_NOTID:	bits |= 0x00; break;
+		}
+		switch (diga->status[0] & IEC958_AES0_PRO_EMPHASIS) {
+		case IEC958_AES0_PRO_EMPHASIS_NONE: bits |= 0x02; break;
+		case IEC958_AES0_PRO_EMPHASIS_5015: bits |= 0x01; break;
+		case IEC958_AES0_PRO_EMPHASIS_CCITT: bits |= 0x00; break;
+		default:
+		case IEC958_AES0_PRO_EMPHASIS_NOTID: bits |= 0x03; break;
+		}
+		switch (diga->status[1] & IEC958_AES1_PRO_MODE) {
+		case IEC958_AES1_PRO_MODE_TWO:
+		case IEC958_AES1_PRO_MODE_STEREOPHONIC: bits |= 0x00; break;
+		default: bits |= 0x80; break;
+		}
+	}
+	return bits;
+}
+
+#endif /* SND_CS8404 */
+
+#endif /* __SOUND_CS8403_H */