update iso API for multi-channel reception and new packet buffer layout

git-svn-id: svn://svn.linux1394.org/libraw1394/trunk@98 53a565d1-3bb7-0310-b661-cf11e63c67ab

1 files changed, 171 insertions, 86 deletions

diff --git a/src/iso.c b/src/iso.c
index 36d5d25..bacde60 100644
--- a/src/iso.c
+++ b/src/iso.c
@@ -113,34 +113,41 @@ static int do_iso_init(raw1394handle_t handle,
 		       int channel,
 		       enum raw1394_iso_speed speed,
 		       int irq_interval,
-		       int xmit)
+		       int cmd)
 {
-	size_t pgsize;
+	unsigned int bufsize, stride;
 
 	/* already initialized? */
 	if(handle->iso_buffer)
 		return -1;
-	
+
+	/* choose a power-of-two stride for the packet data buffer,
+	   so that an even number of packets fits on one page */
+	for(stride = 4; stride < max_packet_size; stride *= 2);
+
+	if(stride > getpagesize()) {
+		errno = ENOMEM;
+		return -1;
+	}
+
+	handle->iso_buf_stride = stride;
+
+	handle->iso_status.config.data_buf_size = stride * buf_packets;
 	handle->iso_status.config.buf_packets = buf_packets;
-	handle->iso_status.config.max_packet_size = max_packet_size;
 	handle->iso_status.config.channel = channel;
 	handle->iso_status.config.speed = speed;
 	handle->iso_status.config.irq_interval = irq_interval;
-	
-	if(ioctl(handle->fd, xmit ? RAW1394_ISO_XMIT_INIT : RAW1394_ISO_RECV_INIT, &handle->iso_status))
-		return -1;
 
-	handle->iso_buffer_bytes = handle->iso_status.config.buf_packets * handle->iso_status.buf_stride;
-
-	/* make sure buffer is a multiple of the page size (for mmap) */
-	pgsize = getpagesize();
-	if(handle->iso_buffer_bytes % pgsize)
-		handle->iso_buffer_bytes += pgsize - (handle->iso_buffer_bytes % pgsize);
+	if(ioctl(handle->fd, cmd, &handle->iso_status))
+		return -1;
 
 	/* mmap the DMA buffer */
-	handle->iso_buffer = mmap(NULL, handle->iso_buffer_bytes, PROT_READ | PROT_WRITE,
+	/* (we assume the kernel sets buf_size to an even number of pages) */
+	handle->iso_buffer = mmap(NULL,
+				  handle->iso_status.config.data_buf_size,
+				  PROT_READ | PROT_WRITE,
 				  MAP_SHARED, handle->fd, 0);
-	
+
 	if(handle->iso_buffer == (unsigned char*) MAP_FAILED) {
 		handle->iso_buffer = NULL;
 		ioctl(handle->fd, RAW1394_ISO_SHUTDOWN, 0);
@@ -149,10 +156,10 @@ static int do_iso_init(raw1394handle_t handle,
 
 	handle->iso_status.overflows = 0;
 	handle->iso_packets_dropped = 0;
-	
+
 	handle->iso_xmit_handler = NULL;
 	handle->iso_recv_handler = NULL;
-	
+
 	return 0;			
 }
 
@@ -171,14 +178,17 @@ int raw1394_iso_xmit_init(raw1394handle_t handle,
 			  raw1394_iso_xmit_handler_t handler,
 			  unsigned int buf_packets,
 			  unsigned int max_packet_size,
-			  int channel,
+			  unsigned char channel,
 			  enum raw1394_iso_speed speed,
 			  int irq_interval)
 {
-	if(do_iso_init(handle, buf_packets, max_packet_size, channel, speed, irq_interval, 1))
+	if(do_iso_init(handle, buf_packets, max_packet_size, channel, speed,
+		       irq_interval, RAW1394_ISO_XMIT_INIT))
 		return -1;
-	
+
 	handle->iso_xmit_handler = handler;
+	handle->next_packet = 0;
+
 	return 0;
 }
 
@@ -197,11 +207,12 @@ int raw1394_iso_recv_init(raw1394handle_t handle,
 			  raw1394_iso_recv_handler_t handler,
 			  unsigned int buf_packets,
 			  unsigned int max_packet_size,
-			  int channel,
+			  unsigned char channel,
 			  int irq_interval)
 {
 	/* any speed will work */
-	if(do_iso_init(handle, buf_packets, max_packet_size, channel, RAW1394_ISO_SPEED_100, irq_interval, 0))
+	if(do_iso_init(handle, buf_packets, max_packet_size, channel, RAW1394_ISO_SPEED_100,
+		       irq_interval, RAW1394_ISO_RECV_INIT))
 		return -1;
 
 	handle->iso_recv_handler = handler;
@@ -209,6 +220,74 @@ int raw1394_iso_recv_init(raw1394handle_t handle,
 }
 
 /**
+ * raw1394_iso_multichannel_recv_init - initialize multi-channel isochronous reception
+ * @handler: handler function for receiving packets
+ * @buf_packets: number of isochronous packets to buffer
+ * @max_packet_size: largest packet you need to handle, in bytes (not including the isochronous header)
+ * @speed: speed at which to receive
+ * @irq_interval: maximum latency of wake-ups, in packets (-1 if you don't care)
+ *
+ * Allocates all user and kernel resources necessary for isochronous reception.
+ **/
+int raw1394_iso_multichannel_recv_init(raw1394handle_t handle,
+				       raw1394_iso_recv_handler_t handler,
+				       unsigned int buf_packets,
+				       unsigned int max_packet_size,
+				       int irq_interval)
+{
+	/* any speed will work */
+	if(do_iso_init(handle, buf_packets, max_packet_size, -1, RAW1394_ISO_SPEED_100,
+		       irq_interval, RAW1394_ISO_RECV_INIT))
+		return -1;
+
+	handle->iso_recv_handler = handler;
+	return 0;
+}
+
+/**
+ * raw1394_iso_recv_listen_channel - listen to a specific channel in multi-channel mode
+ **/
+int raw1394_iso_recv_listen_channel(raw1394handle_t handle, unsigned char channel)
+{
+	if(!handle->iso_buffer)
+		return -1;
+	if(!handle->iso_recv_handler)
+		return -1;
+
+	return ioctl(handle->fd, RAW1394_ISO_RECV_LISTEN_CHANNEL, channel);
+}
+
+/**
+ * raw1394_iso_recv_unlisten_channel - stop listening  to a specific channel in multi-channel mode
+ **/
+int raw1394_iso_recv_unlisten_channel(raw1394handle_t handle, unsigned char channel)
+{
+	if(!handle->iso_buffer)
+		return -1;
+	if(!handle->iso_recv_handler)
+		return -1;
+
+	return ioctl(handle->fd, RAW1394_ISO_RECV_UNLISTEN_CHANNEL, channel);
+}
+
+/**
+ * raw1394_iso_recv_set_channel_mask - listen or unlisten to a whole bunch of channels at once
+ * @mask: 64-bit mask of channels, 1 means listen, 0 means unlisten,
+ *        channel 0 is LSB, channel 63 is MSB
+ *
+ * for multi-channel reception mode only
+ **/
+int raw1394_iso_recv_set_channel_mask(raw1394handle_t handle, u_int64_t mask)
+{
+	if(!handle->iso_buffer)
+		return -1;
+	if(!handle->iso_recv_handler)
+		return -1;
+
+	return ioctl(handle->fd, RAW1394_ISO_RECV_SET_CHANNEL_MASK, (void*) &mask);
+}
+
+/**
  * raw1394_iso_recv_start - begin isochronous reception
  * @start_on_cycle: isochronous cycle number on which to start (-1 if you don't care)
  **/
@@ -218,7 +297,7 @@ int raw1394_iso_recv_start(raw1394handle_t handle, int start_on_cycle)
 		return -1;
 	if(!handle->iso_recv_handler)
 		return -1;
-	
+
 	if(ioctl(handle->fd, RAW1394_ISO_RECV_START, start_on_cycle))
 		return -1;
 
@@ -229,67 +308,66 @@ int raw1394_iso_recv_start(raw1394handle_t handle, int start_on_cycle)
 static int _raw1394_iso_xmit_queue_packets(raw1394handle_t handle)
 {
 	struct raw1394_iso_status *stat = &handle->iso_status;
-	int retval = 0, packets_done = 0;
-	
+	struct raw1394_iso_packets packets;
+	int retval = -1;
+
 	if(!handle->iso_buffer)
-		return -1;
+		goto out;
 
 	if(!handle->iso_xmit_handler)
-		return -1;
-	
+		goto out;
+
+	/* we could potentially send up to stat->n_packets packets */
+	packets.n_packets = 0;
+	packets.infos = malloc(stat->n_packets * sizeof(struct raw1394_iso_packet_info));
+	if(packets.infos == NULL)
+		goto out;
+
 	while(stat->n_packets > 0) {
 		enum raw1394_iso_disposition disp;
-		unsigned char *packet_data;
-		struct raw1394_iso_packet_info *info;
 		unsigned int len;
-		unsigned char tag, sy;
-		
-		packet_data = handle->iso_buffer + stat->first_packet * stat->buf_stride
-			                         + stat->packet_data_offset;
 		
-		info = (struct raw1394_iso_packet_info*) (handle->iso_buffer
-							  + stat->first_packet * stat->buf_stride
-							  + stat->packet_info_offset);
+		struct raw1394_iso_packet_info *info = &packets.infos[packets.n_packets];
+
+		info->offset = handle->iso_buf_stride * handle->next_packet;
 		
 		/* call handler */
 		disp = handle->iso_xmit_handler(handle,
-						packet_data,
-						&len, &tag, &sy,
-						info->cycle,
+						handle->iso_buffer + info->offset,
+						&len,
+						&info->tag, &info->sy,
+						stat->xmit_cycle,
 						_raw1394_iso_dropped(handle));
-
-		/* check if packet is too long */
-		if(len > stat->config.max_packet_size) {
-			retval = -1;
-			break;
-		}
-	
-		/* set packet metadata */
 		info->len = len;
-		info->tag = tag;
-		info->sy = sy;
 		
 		/* advance packet cursors and cycle counter */
 		stat->n_packets--;
-		stat->first_packet = (stat->first_packet + 1) % stat->config.buf_packets;
-		packets_done++;
+		handle->next_packet = (handle->next_packet + 1) % stat->config.buf_packets;
+		if(stat->xmit_cycle != -1)
+			stat->xmit_cycle = (stat->xmit_cycle + 1) % 8000;
+		packets.n_packets++;
 
 		if(disp == RAW1394_ISO_DEFER) {
 			/* queue an event so that we don't hang in the next read() */
 			if(ioctl(handle->fd, RAW1394_ISO_QUEUE_ACTIVITY, 0))
-				return -1;
+				goto out_produce;
 			break;
 		} else if(disp == RAW1394_ISO_ERROR) {
-			retval = -1;
-			break;
+			goto out_produce;
 		}
 	}
 
-	if(packets_done > 0) {
-		if(ioctl(handle->fd, RAW1394_ISO_PRODUCE_CONSUME, packets_done))
-			return -1;
+	/* success */
+	retval = 0;
+
+out_produce:
+	if(packets.n_packets > 0) {
+		if(ioctl(handle->fd, RAW1394_ISO_XMIT_PACKETS, &packets))
+			retval = -1;
 	}
-	
+out_free:
+	free(packets.infos);
+out:	
 	return retval;
 }
 
@@ -302,7 +380,7 @@ static int _raw1394_iso_xmit_queue_packets(raw1394handle_t handle)
 int raw1394_iso_xmit_start(raw1394handle_t handle, int start_on_cycle, int prebuffer_packets)
 {
 	int args[2];
-	
+
 	if(!handle->iso_buffer)
 		return -1;
 	if(!handle->iso_xmit_handler)
@@ -310,10 +388,10 @@ int raw1394_iso_xmit_start(raw1394handle_t handle, int start_on_cycle, int prebu
 
 	args[0] = start_on_cycle;
 	args[1] = prebuffer_packets;
-	
+
 	if(ioctl(handle->fd, RAW1394_ISO_XMIT_START, &args[0]))
 		return -1;
-	
+
 	return 0;
 }
 
@@ -324,7 +402,7 @@ void raw1394_iso_stop(raw1394handle_t handle)
 {
 	if(!handle->iso_buffer)
 		return;
-	
+
 	ioctl(handle->fd, RAW1394_ISO_STOP, 0);
 }
 
@@ -335,7 +413,7 @@ void raw1394_iso_shutdown(raw1394handle_t handle)
 {
 	if(handle->iso_buffer) {
 		raw1394_iso_stop(handle);
-		munmap(handle->iso_buffer, handle->iso_buffer_bytes);
+		munmap(handle->iso_buffer, handle->iso_status.config.data_buf_size);
 		ioctl(handle->fd, RAW1394_ISO_SHUTDOWN, 0);
 		handle->iso_buffer = NULL;
 	}
@@ -344,31 +422,34 @@ void raw1394_iso_shutdown(raw1394handle_t handle)
 static int _raw1394_iso_recv_packets(raw1394handle_t handle)
 {
 	struct raw1394_iso_status *stat = &handle->iso_status;
-	struct raw1394_iso_packet_info *info;
+	struct raw1394_iso_packets packets;
+
+	int retval = -1, packets_done = 0;
 
-	int retval = 0, packets_done = 0;
-	
 	if(!handle->iso_buffer)
-		return -1;
+		goto out;
 
 	if(!handle->iso_recv_handler)
-		return -1;
-	
+		goto out;
+
+	/* ask the kernel to fill an array with packet info structs */
+	packets.n_packets = stat->n_packets;
+	packets.infos = malloc(packets.n_packets * sizeof(struct raw1394_iso_packet_info));
+	if(packets.infos == NULL)
+		goto out;
+
+	if(ioctl(handle->fd, RAW1394_ISO_RECV_PACKETS, &packets) < 0)
+		goto out_free;
+
 	while(stat->n_packets > 0) {
-		unsigned char *packet_data;
 		struct raw1394_iso_packet_info *info;
 		enum raw1394_iso_disposition disp;
-		
-		packet_data = handle->iso_buffer + stat->first_packet * stat->buf_stride
-			                         + stat->packet_data_offset;
 
-		info = (struct raw1394_iso_packet_info*) (handle->iso_buffer
-							  + stat->first_packet * stat->buf_stride
-							  + stat->packet_info_offset);
+		info = &packets.infos[packets_done];
 
 		/* call handler */
 		disp = handle->iso_recv_handler(handle,
-						packet_data,
+						handle->iso_buffer + info->offset,
 						info->len, info->channel,
 						info->tag, info->sy,
 						info->cycle,
@@ -376,25 +457,29 @@ static int _raw1394_iso_recv_packets(raw1394handle_t handle)
 
 		/* advance packet cursors */
 		stat->n_packets--;
-		stat->first_packet = (stat->first_packet + 1) % stat->config.buf_packets;
 		packets_done++;
 		
 		if(disp == RAW1394_ISO_DEFER) {
 			/* queue an event so that we don't hang in the next read() */
 			if(ioctl(handle->fd, RAW1394_ISO_QUEUE_ACTIVITY, 0))
-				return -1;
+				goto out_consume;
 			break;
 		} else if(disp == RAW1394_ISO_ERROR) {
-			retval = -1;
-			break;
+			goto out_consume;
 		}
 	}
 
+	/* success */
+	retval = 0;
+
+out_consume:
 	if(packets_done > 0) {
-		if(ioctl(handle->fd, RAW1394_ISO_PRODUCE_CONSUME, packets_done))
-			return -1;
+		if(ioctl(handle->fd, RAW1394_ISO_RECV_RELEASE_PACKETS, packets_done))
+			retval = -1;
 	}
-	
+out_free:
+	free(packets.infos);
+out:	
 	return retval;
 }
 
@@ -417,7 +502,7 @@ int _raw1394_iso_iterate(raw1394handle_t handle)
 	} else if(handle->iso_recv_handler) {
 		return _raw1394_iso_recv_packets(handle);
 	}
-	
+
 	return 0;
 }