[media] dvb_usb_v2: dynamic USB stream URB configuration

Change URB count, buffer size and type [BULK/ISOC]
dynamically when needed if existing URB buffers are
big enough.
Signed-off-by: NAntti Palosaari <crope@iki.fi>
Signed-off-by: NMauro Carvalho Chehab <mchehab@redhat.com>

drivers/media/dvb/dvb-usb/dvb_usb_common.h

@@ -33,7 +33,8 @@ extern int dvb_usb_device_power_ctrl(struct dvb_usb_device *d, int onoff);
 extern int usb_urb_init(struct usb_data_stream *stream,
 		struct usb_data_stream_properties *props);
 extern int usb_urb_exit(struct usb_data_stream *stream);
-extern int usb_urb_submit(struct usb_data_stream *stream);
+extern int usb_urb_submit(struct usb_data_stream *stream,
+		struct usb_data_stream_properties *props);
 extern int usb_urb_kill(struct usb_data_stream *stream);
 
 extern int dvb_usb_adapter_stream_init(struct dvb_usb_adapter *adap);

drivers/media/dvb/dvb-usb/dvb_usb_dvb.c

@@ -57,7 +57,7 @@ static int dvb_usb_ctrl_feed(struct dvb_demux_feed *dvbdmxfeed, int onoff)
 	 */
 	if (adap->feedcount == onoff && adap->feedcount > 0) {
 		deb_ts("submitting all URBs\n");
-		usb_urb_submit(&adap->fe_adap[adap->active_fe].stream);
+		usb_urb_submit(&adap->fe_adap[adap->active_fe].stream, NULL);
 
 		deb_ts("controlling pid parser\n");
 		if (adap->props.fe[adap->active_fe].caps & DVB_USB_ADAP_HAS_PID_FILTER &&

drivers/media/dvb/dvb-usb/usb_urb.c

@@ -11,6 +11,10 @@
 #include "dvb_usb_common.h"
 
 /* URB stuff for streaming */
+
+int usb_urb_reconfig(struct usb_data_stream *stream,
+		struct usb_data_stream_properties *props);
+
 static void usb_urb_complete(struct urb *urb)
 {
 	struct usb_data_stream *stream = urb->context;
@@ -79,9 +83,17 @@ int usb_urb_kill(struct usb_data_stream *stream)
 	return 0;
 }
 
-int usb_urb_submit(struct usb_data_stream *stream)
+int usb_urb_submit(struct usb_data_stream *stream,
+		struct usb_data_stream_properties *props)
 {
 	int i, ret;
+
+	if (props) {
+		ret = usb_urb_reconfig(stream, props);
+		if (ret < 0)
+			return ret;
+	}
+
 	for (i = 0; i < stream->urbs_initialized; i++) {
 		deb_ts("submitting URB no. %d\n", i);
 		ret = usb_submit_urb(stream->urb_list[i], GFP_ATOMIC);
@@ -96,65 +108,32 @@ int usb_urb_submit(struct usb_data_stream *stream)
 	return 0;
 }
 
-static int usb_free_stream_buffers(struct usb_data_stream *stream)
+int usb_urb_free_urbs(struct usb_data_stream *stream)
 {
-	if (stream->state & USB_STATE_URB_BUF) {
-		while (stream->buf_num) {
-			stream->buf_num--;
-			deb_mem("freeing buffer %d\n", stream->buf_num);
-			usb_free_coherent(stream->udev, stream->buf_size,
-					  stream->buf_list[stream->buf_num],
-					  stream->dma_addr[stream->buf_num]);
-		}
-	}
-
-	stream->state &= ~USB_STATE_URB_BUF;
-
-	return 0;
-}
-
-static int usb_allocate_stream_buffers(struct usb_data_stream *stream, int num,
-		unsigned long size)
-{
-	stream->buf_num = 0;
-	stream->buf_size = size;
+	int i;
 
-	deb_mem("all in all I will use %lu bytes for streaming\n", num * size);
+	usb_urb_kill(stream);
 
-	for (stream->buf_num = 0; stream->buf_num < num; stream->buf_num++) {
-		deb_mem("allocating buffer %d\n", stream->buf_num);
-		stream->buf_list[stream->buf_num] = usb_alloc_coherent(
-				stream->udev, size, GFP_ATOMIC,
-				&stream->dma_addr[stream->buf_num]);
-		if (stream->buf_list[stream->buf_num] == NULL) {
-			deb_mem("not enough memory for urb-buffer" \
-					" allocation.\n");
-			usb_free_stream_buffers(stream);
-			return -ENOMEM;
+	for (i = 0; i < stream->urbs_initialized; i++) {
+		if (stream->urb_list[i] != NULL) {
+			deb_mem("freeing URB no. %d.\n", i);
+			pr_debug("%s: free URB=%d\n", __func__, i);
+			/* free the URBs */
+			usb_free_urb(stream->urb_list[i]);
 		}
-		deb_mem("buffer %d: %p (dma: %llu)\n",
-				stream->buf_num,
-				stream->buf_list[stream->buf_num],
-				(long long)stream->dma_addr[stream->buf_num]);
-		memset(stream->buf_list[stream->buf_num], 0, size);
-		stream->state |= USB_STATE_URB_BUF;
 	}
-	deb_mem("allocation successful\n");
+	stream->urbs_initialized = 0;
 
 	return 0;
 }
 
-static int usb_bulk_urb_init(struct usb_data_stream *stream)
+static int usb_urb_alloc_bulk_urbs(struct usb_data_stream *stream)
 {
 	int i, j;
 
-	i = usb_allocate_stream_buffers(stream, stream->props.count,
-			stream->props.u.bulk.buffersize);
-	if (i < 0)
-		return i;
-
 	/* allocate the URBs */
 	for (i = 0; i < stream->props.count; i++) {
+		pr_debug("%s: alloc URB=%d\n", __func__, i);
 		stream->urb_list[i] = usb_alloc_urb(0, GFP_ATOMIC);
 		if (!stream->urb_list[i]) {
 			deb_mem("not enough memory for urb_alloc_urb!.\n");
@@ -162,9 +141,10 @@ static int usb_bulk_urb_init(struct usb_data_stream *stream)
 				usb_free_urb(stream->urb_list[j]);
 			return -ENOMEM;
 		}
-		usb_fill_bulk_urb(stream->urb_list[i], stream->udev,
+		usb_fill_bulk_urb(stream->urb_list[i],
+				stream->udev,
 				usb_rcvbulkpipe(stream->udev,
-					stream->props.endpoint),
+						stream->props.endpoint),
 				stream->buf_list[i],
 				stream->props.u.bulk.buffersize,
 				usb_urb_complete, stream);
@@ -176,21 +156,15 @@ static int usb_bulk_urb_init(struct usb_data_stream *stream)
 	return 0;
 }
 
-static int usb_isoc_urb_init(struct usb_data_stream *stream)
+static int usb_urb_alloc_isoc_urbs(struct usb_data_stream *stream)
 {
 	int i, j;
 
-	i = usb_allocate_stream_buffers(stream, stream->props.count,
-			stream->props.u.isoc.framesize *
-			stream->props.u.isoc.framesperurb);
-	if (i < 0)
-		return i;
-
 	/* allocate the URBs */
 	for (i = 0; i < stream->props.count; i++) {
 		struct urb *urb;
 		int frame_offset = 0;
-
+		pr_debug("%s: alloc URB=%d\n", __func__, i);
 		stream->urb_list[i] = usb_alloc_urb(
 				stream->props.u.isoc.framesperurb, GFP_ATOMIC);
 		if (!stream->urb_list[i]) {
@@ -210,7 +184,8 @@ static int usb_isoc_urb_init(struct usb_data_stream *stream)
 		urb->transfer_flags = URB_ISO_ASAP | URB_NO_TRANSFER_DMA_MAP;
 		urb->interval = stream->props.u.isoc.interval;
 		urb->number_of_packets = stream->props.u.isoc.framesperurb;
-		urb->transfer_buffer_length = stream->buf_size;
+		urb->transfer_buffer_length = stream->props.u.isoc.framesize *
+				stream->props.u.isoc.framesperurb;
 		urb->transfer_buffer = stream->buf_list[i];
 		urb->transfer_dma = stream->dma_addr[i];
 
@@ -226,9 +201,110 @@ static int usb_isoc_urb_init(struct usb_data_stream *stream)
 	return 0;
 }
 
+int usb_free_stream_buffers(struct usb_data_stream *stream)
+{
+	if (stream->state & USB_STATE_URB_BUF) {
+		while (stream->buf_num) {
+			stream->buf_num--;
+			deb_mem("freeing buffer %d\n", stream->buf_num);
+			usb_free_coherent(stream->udev, stream->buf_size,
+					  stream->buf_list[stream->buf_num],
+					  stream->dma_addr[stream->buf_num]);
+		}
+	}
+
+	stream->state &= ~USB_STATE_URB_BUF;
+
+	return 0;
+}
+
+int usb_alloc_stream_buffers(struct usb_data_stream *stream, int num,
+		unsigned long size)
+{
+	stream->buf_num = 0;
+	stream->buf_size = size;
+
+	deb_mem("all in all I will use %lu bytes for streaming\n", num * size);
+
+	for (stream->buf_num = 0; stream->buf_num < num; stream->buf_num++) {
+		deb_mem("allocating buffer %d\n", stream->buf_num);
+		stream->buf_list[stream->buf_num] = usb_alloc_coherent(
+				stream->udev, size, GFP_ATOMIC,
+				&stream->dma_addr[stream->buf_num]);
+		if (stream->buf_list[stream->buf_num] == NULL) {
+			deb_mem("not enough memory for urb-buffer" \
+					" allocation.\n");
+			usb_free_stream_buffers(stream);
+			return -ENOMEM;
+		}
+		deb_mem("buffer %d: %p (dma: %llu)\n",
+				stream->buf_num,
+				stream->buf_list[stream->buf_num],
+				(long long)stream->dma_addr[stream->buf_num]);
+		memset(stream->buf_list[stream->buf_num], 0, size);
+		stream->state |= USB_STATE_URB_BUF;
+	}
+	deb_mem("allocation successful\n");
+
+	return 0;
+}
+
+int usb_urb_reconfig(struct usb_data_stream *stream,
+		struct usb_data_stream_properties *props)
+{
+	int buf_size;
+
+	if (props == NULL)
+		return 0;
+
+	/* check allocated buffers are large enough for the request */
+	if (props->type == USB_BULK)
+		buf_size = stream->props.u.bulk.buffersize;
+	else if (props->type == USB_ISOC)
+		buf_size = props->u.isoc.framesize * props->u.isoc.framesperurb;
+	else
+		return -EINVAL;
+
+	if (stream->buf_num < props->count || stream->buf_size < buf_size) {
+		err("cannot reconfigure as allocated buffers are too small");
+		return -EINVAL;
+	}
+
+	/* check if all fields are same */
+	if (stream->props.type == props->type &&
+			stream->props.count == props->count &&
+			stream->props.endpoint == props->endpoint) {
+		if (props->type == USB_BULK &&
+				props->u.bulk.buffersize ==
+				stream->props.u.bulk.buffersize)
+			return 0;
+		else if (props->type == USB_ISOC &&
+				props->u.isoc.framesperurb ==
+				stream->props.u.isoc.framesperurb &&
+				props->u.isoc.framesize ==
+				stream->props.u.isoc.framesize &&
+				props->u.isoc.interval ==
+				stream->props.u.isoc.interval)
+			return 0;
+	}
+
+	pr_debug("%s: re-alloc URBs\n", __func__);
+
+	usb_urb_free_urbs(stream);
+	memcpy(&stream->props, props, sizeof(*props));
+	if (props->type == USB_BULK)
+		return usb_urb_alloc_bulk_urbs(stream);
+	else if (props->type == USB_ISOC)
+		return usb_urb_alloc_isoc_urbs(stream);
+
+	return 0;
+}
+
 int usb_urb_init(struct usb_data_stream *stream,
 		struct usb_data_stream_properties *props)
 {
+	int ret;
+
 	if (stream == NULL || props == NULL)
 		return -EINVAL;
 
@@ -244,9 +320,20 @@ int usb_urb_init(struct usb_data_stream *stream,
 
 	switch (stream->props.type) {
 	case USB_BULK:
-		return usb_bulk_urb_init(stream);
+		ret = usb_alloc_stream_buffers(stream, stream->props.count,
+				stream->props.u.bulk.buffersize);
+		if (ret < 0)
+			return ret;
+
+		return usb_urb_alloc_bulk_urbs(stream);
 	case USB_ISOC:
-		return usb_isoc_urb_init(stream);
+		ret = usb_alloc_stream_buffers(stream, stream->props.count,
+				stream->props.u.isoc.framesize *
+				stream->props.u.isoc.framesperurb);
+		if (ret < 0)
+			return ret;
+
+		return usb_urb_alloc_isoc_urbs(stream);
 	default:
 		err("unknown URB-type for data transfer.");
 		return -EINVAL;
@@ -255,19 +342,8 @@ int usb_urb_init(struct usb_data_stream *stream,
 
 int usb_urb_exit(struct usb_data_stream *stream)
 {
-	int i;
-
-	usb_urb_kill(stream);
-
-	for (i = 0; i < stream->urbs_initialized; i++) {
-		if (stream->urb_list[i] != NULL) {
-			deb_mem("freeing URB no. %d.\n", i);
-			/* free the URBs */
-			usb_free_urb(stream->urb_list[i]);
-		}
-	}
-	stream->urbs_initialized = 0;
-
+	usb_urb_free_urbs(stream);
 	usb_free_stream_buffers(stream);
+
 	return 0;
 }