[PATCH 4/5] ALSA: firewire-lib: fix calculation for size of IR context payload
From: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Date: 2021-05-13 12:57:06
Also in:
alsa-devel
Subsystem:
firewire audio drivers and iec 61883-1/6 packet streaming engine, sound, the rest · Maintainers:
Clemens Ladisch, Takashi Sakamoto, Jaroslav Kysela, Takashi Iwai, Linus Torvalds
The quadlets for CIP header is handled as a part of IR context header,
thus it doesn't join in IR context payload. However current calculation
includes the quadlets in IR context payload.
Cc: <redacted>
Fixes: f11453c7cc01 ("ALSA: firewire-lib: use 16 bytes IR context header to separate CIP header")
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
sound/firewire/amdtp-stream.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index b53971bf4b90..73aff017dc9a 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c@@ -1071,23 +1071,22 @@ static int amdtp_stream_start(struct amdtp_stream *s, int channel, int speed, s->data_block_counter = 0; } - /* initialize packet buffer */ + // initialize packet buffer. + max_ctx_payload_size = amdtp_stream_get_max_payload(s); if (s->direction == AMDTP_IN_STREAM) { dir = DMA_FROM_DEVICE; type = FW_ISO_CONTEXT_RECEIVE; - if (!(s->flags & CIP_NO_HEADER)) + if (!(s->flags & CIP_NO_HEADER)) { + max_ctx_payload_size -= 8; ctx_header_size = IR_CTX_HEADER_SIZE_CIP; - else + } else { ctx_header_size = IR_CTX_HEADER_SIZE_NO_CIP; - - max_ctx_payload_size = amdtp_stream_get_max_payload(s) - - ctx_header_size; + } } else { dir = DMA_TO_DEVICE; type = FW_ISO_CONTEXT_TRANSMIT; ctx_header_size = 0; // No effect for IT context. - max_ctx_payload_size = amdtp_stream_get_max_payload(s); if (!(s->flags & CIP_NO_HEADER)) max_ctx_payload_size -= IT_PKT_HEADER_SIZE_CIP; }
--
2.27.0