[PATCH 5.12 047/127] ALSA: firewire-lib: fix calculation for size of IR context payload
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-05-24 16:04:26
Also in:
lkml
From: Takashi Sakamoto <o-takashi@sakamocchi.jp>
commit 1be4f21d9984fa9835fae5411a29465dc5aece6f upstream.
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>
Link: https://lore.kernel.org/r/20210513125652.110249-5-o-takashi@sakamocchi.jp (local)
Signed-off-by: Takashi Iwai <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
sound/firewire/amdtp-stream.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c@@ -1068,23 +1068,22 @@ static int amdtp_stream_start(struct amd 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; }