firewire: Use a buffer fill descriptor for receive when header size is 0.

When the DMA is setup to not strip any headers, we need to use
the buffer fill descriptor instead of the dual buffer, since the
dual buffer descriptor must strip a non-zero number of header quadlets.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
diff --git a/drivers/firewire/fw-ohci.c b/drivers/firewire/fw-ohci.c
index 76ac70a..9b9ea0f 100644
--- a/drivers/firewire/fw-ohci.c
+++ b/drivers/firewire/fw-ohci.c
@@ -1267,16 +1267,34 @@
 	spin_unlock_irqrestore(&ohci->lock, flags);
 	return retval;
 }
+ 
+static int handle_ir_bufferfill_packet(struct context *context,
+				       struct descriptor *d,
+				       struct descriptor *last)
+{
+	struct iso_context *ctx =
+		container_of(context, struct iso_context, context);
 
-static int handle_ir_packet(struct context *context,
-			    struct descriptor *d,
-			    struct descriptor *last)
+	if (d->res_count > 0)
+		return 0;
+
+	if (le16_to_cpu(last->control) & descriptor_irq_always)
+		ctx->base.callback(&ctx->base,
+				   le16_to_cpu(last->res_count),
+				   0, NULL, ctx->base.callback_data);
+
+	return 1;
+}
+
+static int handle_ir_dualbuffer_packet(struct context *context,
+				       struct descriptor *d,
+				       struct descriptor *last)
 {
 	struct iso_context *ctx =
 		container_of(context, struct iso_context, context);
 	struct db_descriptor *db = (struct db_descriptor *) d;
 	size_t header_length;
- 
+
 	if (db->first_res_count > 0 && db->second_res_count > 0)
 		/* This descriptor isn't done yet, stop iteration. */
 		return 0;
@@ -1317,7 +1335,7 @@
 }
 
 static struct fw_iso_context *
-ohci_allocate_iso_context(struct fw_card *card, int type)
+ohci_allocate_iso_context(struct fw_card *card, int type, size_t header_size)
 {
 	struct fw_ohci *ohci = fw_ohci(card);
 	struct iso_context *ctx, *list;
@@ -1333,7 +1351,10 @@
 	} else {
  		mask = &ohci->ir_context_mask;
  		list = ohci->ir_context_list;
-		callback = handle_ir_packet;
+		if (header_size > 0)
+			callback = handle_ir_dualbuffer_packet;
+		else
+			callback = handle_ir_bufferfill_packet;
 	}
 
 	spin_lock_irqsave(&ohci->lock, flags);
@@ -1378,7 +1399,7 @@
 {
  	struct iso_context *ctx = container_of(base, struct iso_context, base);
 	struct fw_ohci *ohci = ctx->context.ohci;
-	u32 cycle_match = 0;
+	u32 cycle_match = 0, mode;
 	int index;
 
 	if (ctx->base.type == FW_ISO_CONTEXT_TRANSMIT) {
@@ -1393,11 +1414,15 @@
 	} else {
 		index = ctx - ohci->ir_context_list;
 
+		if (ctx->base.header_size > 0)
+			mode = IR_CONTEXT_DUAL_BUFFER_MODE;
+		else
+			mode = IR_CONTEXT_BUFFER_FILL;
 		reg_write(ohci, OHCI1394_IsoRecvIntEventClear, 1 << index);
 		reg_write(ohci, OHCI1394_IsoRecvIntMaskSet, 1 << index);
 		reg_write(ohci, context_match(ctx->context.regs),
 			  0xf0000000 | ctx->base.channel);
-		context_run(&ctx->context, IR_CONTEXT_DUAL_BUFFER_MODE);
+		context_run(&ctx->context, mode);
 	}
 
 	return 0;
@@ -1544,10 +1569,10 @@
 }
 
 static int
-ohci_queue_iso_receive(struct fw_iso_context *base,
-		       struct fw_iso_packet *packet,
-		       struct fw_iso_buffer *buffer,
-		       unsigned long payload)
+ohci_queue_iso_receive_dualbuffer(struct fw_iso_context *base,
+				  struct fw_iso_packet *packet,
+				  struct fw_iso_buffer *buffer,
+				  unsigned long payload)
 {
 	struct iso_context *ctx = container_of(base, struct iso_context, base);
 	struct db_descriptor *db = NULL;
@@ -1604,10 +1629,58 @@
 
 	if (p->interrupt)
 		db->control |= cpu_to_le16(descriptor_irq_always);
+
+	return 0;
+}
  
- 	return 0;
- }
+static int
+ohci_queue_iso_receive_bufferfill(struct fw_iso_context *base,
+				  struct fw_iso_packet *packet,
+				  struct fw_iso_buffer *buffer,
+				  unsigned long payload)
+{
+	struct iso_context *ctx = container_of(base, struct iso_context, base);
+	struct descriptor *d = NULL;
+	dma_addr_t d_bus, page_bus;
+	u32 length, rest;
+	int page, offset;
  
+	page   = payload >> PAGE_SHIFT;
+	offset = payload & ~PAGE_MASK;
+	rest   = packet->payload_length;
+
+	while (rest > 0) {
+		d = context_get_descriptors(&ctx->context, 1, &d_bus);
+		if (d == NULL)
+			return -ENOMEM;
+
+		d->control = cpu_to_le16(descriptor_input_more |
+					 descriptor_status |
+					 descriptor_branch_always);
+		
+		if (offset + rest < PAGE_SIZE)
+			length = rest;
+		else
+			length = PAGE_SIZE - offset;
+
+		page_bus = page_private(buffer->pages[page]);
+		d->data_address = cpu_to_le32(page_bus + offset);
+		d->req_count = cpu_to_le16(length);
+		d->res_count = cpu_to_le16(length);
+
+		context_append(&ctx->context, d, 1, 0);
+
+		offset = (offset + length) & ~PAGE_MASK;
+		rest -= length;
+		page++;
+	}
+
+	if (packet->interrupt)
+		d->control |= cpu_to_le16(descriptor_irq_always);
+
+	return 0;
+}
+
 static int
 ohci_queue_iso(struct fw_iso_context *base,
 	       struct fw_iso_packet *packet,
@@ -1616,8 +1689,12 @@
 {
 	if (base->type == FW_ISO_CONTEXT_TRANSMIT)
 		return ohci_queue_iso_transmit(base, packet, buffer, payload);
+	else if (base->header_size == 0)
+		return ohci_queue_iso_receive_bufferfill(base, packet,
+							 buffer, payload);
 	else
-		return ohci_queue_iso_receive(base, packet, buffer, payload);
+		return ohci_queue_iso_receive_dualbuffer(base, packet,
+							 buffer, payload);
 }
 
 static const struct fw_card_driver ohci_driver = {