diff mbox series

[1/2] ALSA: firewire-lib: cache next data_block_counter after probing tracepoints event for IR context

Message ID 20190628055331.1427-2-o-takashi@sakamocchi.jp (mailing list archive)
State New, archived
Headers show
Series ALSA: firewire-lib: fix miss detection from MIDI conformant data channel in AM824 format for IR context | expand

Commit Message

Takashi Sakamoto June 28, 2019, 5:53 a.m. UTC 
For debugging purpose, ALSA IEC 61883-1/6 engine has tracepoints event.
In current implementation, next data block counter is stored as current
data block counter before probing the event for IR isoc context. It's not
good to check current packet parameter.

This commit changes to assign the next data block counter after probing
the event.

Besides, Fireworks devices has a quirk to transfer isoc packet with
data block counter for the last data block. For this quirk, the
assignment is done before calling data block processing layer.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 sound/firewire/amdtp-stream.c | 48 +++++++++++++++++++----------------
 1 file changed, 26 insertions(+), 22 deletions(-)

Comments

Takashi Iwai June 28, 2019, 8:50 a.m. UTC | #1 
On Fri, 28 Jun 2019 07:53:30 +0200,
Takashi Sakamoto wrote:
> 
> For debugging purpose, ALSA IEC 61883-1/6 engine has tracepoints event.
> In current implementation, next data block counter is stored as current
> data block counter before probing the event for IR isoc context. It's not
> good to check current packet parameter.
> 
> This commit changes to assign the next data block counter after probing
> the event.
> 
> Besides, Fireworks devices has a quirk to transfer isoc packet with
> data block counter for the last data block. For this quirk, the
> assignment is done before calling data block processing layer.
> 
> Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

Thanks, applied now.


Takashi
diff mbox series

Patch

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index 3aef6a78a188..b341bd86605e 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -519,13 +519,13 @@  static void build_it_pkt_header(struct amdtp_stream *s, unsigned int cycle,
 
 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 *data_blocks, unsigned int *dbc,
+			    unsigned int *syt)
 {
 	u32 cip_header[2];
 	unsigned int sph;
 	unsigned int fmt;
 	unsigned int fdf;
-	unsigned int data_block_counter;
 	bool lost;
 
 	cip_header[0] = be32_to_cpu(buf[0]);
@@ -577,17 +577,17 @@  static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
 	}
 
 	/* Check data block counter continuity */
-	data_block_counter = cip_header[0] & CIP_DBC_MASK;
+	*dbc = cip_header[0] & CIP_DBC_MASK;
 	if (*data_blocks == 0 && (s->flags & CIP_EMPTY_HAS_WRONG_DBC) &&
 	    s->data_block_counter != UINT_MAX)
-		data_block_counter = s->data_block_counter;
+		*dbc = s->data_block_counter;
 
 	if (((s->flags & CIP_SKIP_DBC_ZERO_CHECK) &&
-	     data_block_counter == s->ctx_data.tx.first_dbc) ||
+	     *dbc == s->ctx_data.tx.first_dbc) ||
 	    s->data_block_counter == UINT_MAX) {
 		lost = false;
 	} else if (!(s->flags & CIP_DBC_IS_END_EVENT)) {
-		lost = data_block_counter != s->data_block_counter;
+		lost = *dbc != s->data_block_counter;
 	} else {
 		unsigned int dbc_interval;
 
@@ -596,26 +596,18 @@  static int check_cip_header(struct amdtp_stream *s, const __be32 *buf,
 		else
 			dbc_interval = *data_blocks;
 
-		lost = data_block_counter !=
-		       ((s->data_block_counter + dbc_interval) & 0xff);
+		lost = *dbc != ((s->data_block_counter + dbc_interval) & 0xff);
 	}
 
 	if (lost) {
 		dev_err(&s->unit->device,
 			"Detect discontinuity of CIP: %02X %02X\n",
-			s->data_block_counter, data_block_counter);
+			s->data_block_counter, *dbc);
 		return -EIO;
 	}
 
 	*syt = cip_header[1] & CIP_SYT_MASK;
 
-	if (s->flags & CIP_DBC_IS_END_EVENT) {
-		s->data_block_counter = data_block_counter;
-	} else {
-		s->data_block_counter =
-				(data_block_counter + *data_blocks) & 0xff;
-	}
-
 	return 0;
 }
 
@@ -626,6 +618,7 @@  static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
 			       unsigned int *syt, unsigned int index)
 {
 	const __be32 *cip_header;
+	unsigned int dbc;
 	int err;
 
 	*payload_length = be32_to_cpu(ctx_header[0]) >> ISO_DATA_LENGTH_SHIFT;
@@ -640,22 +633,33 @@  static int parse_ir_ctx_header(struct amdtp_stream *s, unsigned int cycle,
 	if (!(s->flags & CIP_NO_HEADER)) {
 		cip_header = ctx_header + 2;
 		err = check_cip_header(s, cip_header, *payload_length,
-				       data_blocks, syt);
-		if (err < 0)
-			return err;
+				       data_blocks, &dbc, syt);
+		if (err < 0) {
+			if (err != -EAGAIN)
+				return err;
+
+			*data_blocks = 0;
+			dbc = s->data_block_counter;
+		}
 	} else {
 		cip_header = NULL;
+		err = 0;
 		*data_blocks = *payload_length / sizeof(__be32) /
 			       s->data_block_quadlets;
+		dbc = s->data_block_counter;
 		*syt = 0;
-		s->data_block_counter =
-				(s->data_block_counter + *data_blocks) & 0xff;
 	}
 
+	if (err >= 0 && s->flags & CIP_DBC_IS_END_EVENT)
+		s->data_block_counter = dbc;
+
 	trace_amdtp_packet(s, cycle, cip_header, *payload_length, *data_blocks,
 			   index);
 
-	return 0;
+	if (err >= 0 && !(s->flags & CIP_DBC_IS_END_EVENT))
+		s->data_block_counter = (dbc + *data_blocks) & 0xff;
+
+	return err;
 }
 
 // In CYCLE_TIMER register of IEEE 1394, 7 bits are used to represent second. On