Received-SPF: pass (google.com: domain of linux-kernel+bounces-124904-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: Takashi Sakamoto <o-takashi@sakamocchi.jp>,
	Takashi Iwai <tiwai@suse.de>,
	Sasha Levin <sashal@kernel.org>,
	clemens@ladisch.de,
	perex@perex.cz,
	tiwai@suse.com,
	alsa-devel@alsa-project.org,
	linux-sound@vger.kernel.org
Subject: [PATCH AUTOSEL 6.1 20/52] ALSA: firewire-lib: handle quirk to calculate payload quadlets as data block counter
Date: Fri, 29 Mar 2024 08:45:14 -0400
Message-ID: <20240329124605.3091273-20-sashal@kernel.org>
In-Reply-To: <20240329124605.3091273-1-sashal@kernel.org>
References: <20240329124605.3091273-1-sashal@kernel.org>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

From: Takashi Sakamoto <o-takashi@sakamocchi.jp>

[ Upstream commit 4a486439d2ca85752c46711f373b6ddc107bb35d ]

Miglia Harmony Audio (OXFW970) has a quirk to put the number of
accumulated quadlets in CIP payload into the dbc field of CIP header.

This commit handles the quirk in the packet processing layer.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20240218074128.95210-4-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 sound/firewire/amdtp-stream.c | 12 ++++++++----
 sound/firewire/amdtp-stream.h |  4 ++++
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index f8b644cb9157a..8753125683692 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -771,10 +771,14 @@ static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
 	} else {
 		unsigned int dbc_interval;
 
-		if (*data_blocks > 0 && s->ctx_data.tx.dbc_interval > 0)
-			dbc_interval = s->ctx_data.tx.dbc_interval;
-		else
-			dbc_interval = *data_blocks;
+		if (!(s->flags & CIP_DBC_IS_PAYLOAD_QUADLETS)) {
+			if (*data_blocks > 0 && s->ctx_data.tx.dbc_interval > 0)
+				dbc_interval = s->ctx_data.tx.dbc_interval;
+			else
+				dbc_interval = *data_blocks;
+		} else {
+			dbc_interval = payload_length / sizeof(__be32);
+		}
 
 		lost = dbc != ((*data_block_counter + dbc_interval) & 0xff);
 	}
diff --git a/sound/firewire/amdtp-stream.h b/sound/firewire/amdtp-stream.h
index 1f957c946c956..cf9ab347277f2 100644
--- a/sound/firewire/amdtp-stream.h
+++ b/sound/firewire/amdtp-stream.h
@@ -37,6 +37,9 @@
  *	the value of current SYT_INTERVAL; e.g. initial value is not zero.
  * @CIP_UNAWARE_SYT: For outgoing packet, the value in SYT field of CIP is 0xffff.
  *	For incoming packet, the value in SYT field of CIP is not handled.
+ * @CIP_DBC_IS_PAYLOAD_QUADLETS: Available for incoming packet, and only effective with
+ *	CIP_DBC_IS_END_EVENT flag. The value of dbc field is the number of accumulated quadlets
+ *	in CIP payload, instead of the number of accumulated data blocks.
  */
 enum cip_flags {
 	CIP_NONBLOCKING		= 0x00,
@@ -51,6 +54,7 @@ enum cip_flags {
 	CIP_NO_HEADER		= 0x100,
 	CIP_UNALIGHED_DBC	= 0x200,
 	CIP_UNAWARE_SYT		= 0x400,
+	CIP_DBC_IS_PAYLOAD_QUADLETS = 0x800,
 };
 
 /**
-- 
2.43.0