@@ -549,29 +549,19 @@ static int handle_out_packet_without_header(struct amdtp_stream *s,
return 0;
}
-static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
- const __be32 *ctx_header, __be32 *buffer,
- unsigned int index)
+static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
+ unsigned int payload_length,
+ unsigned int *data_blocks, unsigned int *syt)
{
- unsigned int payload_length;
u32 cip_header[2];
- unsigned int sph, fmt, fdf, syt;
- unsigned int data_block_quadlets, data_block_counter, dbc_interval;
- unsigned int data_blocks;
- struct snd_pcm_substream *pcm;
- unsigned int pcm_frames;
+ unsigned int sph;
+ unsigned int fmt;
+ unsigned int fdf;
+ unsigned int data_block_counter;
bool lost;
- payload_length = be32_to_cpu(ctx_header[0]) >> ISO_DATA_LENGTH_SHIFT;
- if (payload_length > s->ctx_data.tx.max_payload_length) {
- dev_err(&s->unit->device,
- "Detect jumbo payload: %04x %04x\n",
- payload_length, s->ctx_data.tx.max_payload_length);
- return -EIO;
- }
-
- cip_header[0] = be32_to_cpu(buffer[0]);
- cip_header[1] = be32_to_cpu(buffer[1]);
+ cip_header[0] = be32_to_cpu(buf[0]);
+ cip_header[1] = be32_to_cpu(buf[1]);
/*
* This module supports 'Two-quadlet CIP header with SYT field'.
@@ -583,9 +573,7 @@ static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
dev_info_ratelimited(&s->unit->device,
"Invalid CIP header for AMDTP: %08X:%08X\n",
cip_header[0], cip_header[1]);
- data_blocks = 0;
- pcm_frames = 0;
- goto end;
+ return -EAGAIN;
}
/* Check valid protocol or not. */
@@ -595,19 +583,17 @@ static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
dev_info_ratelimited(&s->unit->device,
"Detect unexpected protocol: %08x %08x\n",
cip_header[0], cip_header[1]);
- data_blocks = 0;
- pcm_frames = 0;
- goto end;
+ return -EAGAIN;
}
/* Calculate data blocks */
fdf = (cip_header[1] & CIP_FDF_MASK) >> CIP_FDF_SHIFT;
- if (payload_length < 12 ||
+ if (payload_length < sizeof(__be32) * 2 ||
(fmt == CIP_FMT_AM && fdf == AMDTP_FDF_NO_DATA)) {
- data_blocks = 0;
+ *data_blocks = 0;
} else {
- data_block_quadlets =
- (cip_header[0] & CIP_DBS_MASK) >> CIP_DBS_SHIFT;
+ unsigned int data_block_quadlets =
+ (cip_header[0] & CIP_DBS_MASK) >> CIP_DBS_SHIFT;
/* avoid division by zero */
if (data_block_quadlets == 0) {
dev_err(&s->unit->device,
@@ -618,13 +604,13 @@ static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
if (s->flags & CIP_WRONG_DBS)
data_block_quadlets = s->data_block_quadlets;
- data_blocks = (payload_length / 4 - 2) /
+ *data_blocks = (payload_length / sizeof(__be32) - 2) /
data_block_quadlets;
}
/* Check data block counter continuity */
data_block_counter = cip_header[0] & CIP_DBC_MASK;
- if (data_blocks == 0 && (s->flags & CIP_EMPTY_HAS_WRONG_DBC) &&
+ if (*data_blocks == 0 && (s->flags & CIP_EMPTY_HAS_WRONG_DBC) &&
s->data_block_counter != UINT_MAX)
data_block_counter = s->data_block_counter;
@@ -635,10 +621,12 @@ static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
} else if (!(s->flags & CIP_DBC_IS_END_EVENT)) {
lost = data_block_counter != s->data_block_counter;
} else {
- if (data_blocks > 0 && s->ctx_data.tx.dbc_interval > 0)
+ 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;
+ dbc_interval = *data_blocks;
lost = data_block_counter !=
((s->data_block_counter + dbc_interval) & 0xff);
@@ -651,16 +639,48 @@ static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
return -EIO;
}
- trace_amdtp_packet(s, cycle, buffer, payload_length, data_blocks, index);
-
- syt = be32_to_cpu(buffer[1]) & CIP_SYT_MASK;
- pcm_frames = s->process_data_blocks(s, buffer + 2, data_blocks, &syt);
+ *syt = cip_header[1] & CIP_SYT_MASK;
- if (s->flags & CIP_DBC_IS_END_EVENT)
+ if (s->flags & CIP_DBC_IS_END_EVENT) {
s->data_block_counter = data_block_counter;
- else
+ } else {
s->data_block_counter =
- (data_block_counter + data_blocks) & 0xff;
+ (data_block_counter + *data_blocks) & 0xff;
+ }
+
+ return 0;
+}
+
+static int handle_in_packet(struct amdtp_stream *s, unsigned int cycle,
+ const __be32 *ctx_header, __be32 *buffer,
+ unsigned int index)
+{
+ unsigned int payload_length;
+ unsigned int syt;
+ unsigned int data_blocks;
+ struct snd_pcm_substream *pcm;
+ unsigned int pcm_frames;
+ int err;
+
+ payload_length = be32_to_cpu(ctx_header[0]) >> ISO_DATA_LENGTH_SHIFT;
+ if (payload_length > s->ctx_data.tx.max_payload_length) {
+ dev_err(&s->unit->device,
+ "Detect jumbo payload: %04x %04x\n",
+ payload_length, s->ctx_data.tx.max_payload_length);
+ return -EIO;
+ }
+
+ err = check_cip_header(s, buffer, payload_length, &data_blocks, &syt);
+ if (err < 0) {
+ if (err != -EAGAIN)
+ return err;
+ pcm_frames = 0;
+ goto end;
+ }
+
+ trace_amdtp_packet(s, cycle, buffer, payload_length, data_blocks, index);
+
+ pcm_frames = s->process_data_blocks(s, buffer + 2, data_blocks, &syt);
end:
if (queue_in_packet(s) < 0)
return -EIO;
A parser for CIP header in incoming packet is enough large. This commit splits it into a helper function to better looks of packet handler. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> --- sound/firewire/amdtp-stream.c | 100 ++++++++++++++++++++-------------- 1 file changed, 60 insertions(+), 40 deletions(-)