greybus: record a gbuf's destination CPort id

Rather than indicating whether a gbuf is intended for outbound data,
record its destination CPort id.  That's what's really needed by
the ES1 host driver.  Use CPORT_ID_BAD when the buffer is intended
for inbound data.
Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <greg@kroah.com>

drivers/staging/greybus/es1-ap-usb.c

@@ -97,7 +97,7 @@ static int alloc_gbuf_data(struct gbuf *gbuf, unsigned int size,
 				gfp_t gfp_mask)
 {
 	struct gb_connection *connection = gbuf->operation->connection;
-	u32 cport_reserve = gbuf->outbound ? 1 : 0;
+	u32 cport_reserve = gbuf->dest_cport_id == CPORT_ID_BAD ? 0 : 1;
 	u8 *buffer;
 
 	if (size > ES1_GBUF_MSG_SIZE) {
@@ -130,7 +130,7 @@ static int alloc_gbuf_data(struct gbuf *gbuf, unsigned int size,
 	}
 
 	/* Insert the cport id for outbound buffers */
-	if (gbuf->outbound)
+	if (cport_reserve)
 		*buffer++ = connection->interface_cport_id;
 	gbuf->transfer_buffer = buffer;
 	gbuf->transfer_buffer_length = size;
@@ -147,7 +147,8 @@ static void free_gbuf_data(struct gbuf *gbuf)
 	if (!transfer_buffer)
 		return;
 
-	if (gbuf->outbound)
+	/* Account for the cport id in outbound buffers */
+	if (gbuf->dest_cport_id != CPORT_ID_BAD)
 		transfer_buffer--;	/* Back up to cport id */
 	kfree(transfer_buffer);
 }

drivers/staging/greybus/gbuf.c

@@ -35,8 +35,8 @@ static struct kmem_cache *gbuf_head_cache;
  * hardware designers for this issue...
  */
 struct gbuf *greybus_alloc_gbuf(struct gb_operation *operation,
+				u16 dest_cport_id,
 				unsigned int size,
-				bool outbound,
 				gfp_t gfp_mask)
 {
 	struct greybus_host_device *hd = operation->connection->hd;
@@ -49,7 +49,7 @@ struct gbuf *greybus_alloc_gbuf(struct gb_operation *operation,
 
 	kref_init(&gbuf->kref);
 	gbuf->operation = operation;
-	gbuf->outbound = outbound;
+	gbuf->dest_cport_id = dest_cport_id;
 	gbuf->status = -EBADR;	/* Initial value--means "never set" */
 
 	/* Host controller specific allocation for the actual buffer */

drivers/staging/greybus/greybus.h

@@ -122,12 +122,12 @@ struct gbuf {
 	struct kref kref;
 
 	struct gb_operation *operation;
+	u16 dest_cport_id;		/* Destination CPort id */
 	int status;
+
 	void *transfer_buffer;
 	u32 transfer_buffer_length;
 
-	bool outbound;			/* AP-relative data direction */
-
 	void *hcd_data;			/* for the HCD to track the gbuf */
 };
 
@@ -182,7 +182,7 @@ void greybus_cport_in(struct greybus_host_device *hd, u16 cport_id,
 			u8 *data, size_t length);
 
 struct gbuf *greybus_alloc_gbuf(struct gb_operation *operation,
-				unsigned int size, bool outbound,
+				u16 dest_cport_id, unsigned int size,
 				gfp_t gfp_mask);
 void greybus_free_gbuf(struct gbuf *gbuf);
 struct gbuf *greybus_get_gbuf(struct gbuf *gbuf);

drivers/staging/greybus/operation.c

@@ -203,12 +203,17 @@ static struct gbuf *gb_operation_gbuf_create(struct gb_operation *operation,
 	struct gb_operation_msg_hdr *header;
 	struct gbuf *gbuf;
 	gfp_t gfp_flags = data_out ? GFP_KERNEL : GFP_ATOMIC;
+	u16 dest_cport_id;
 
 	if (size > GB_OPERATION_MESSAGE_SIZE_MAX)
 		return NULL;	/* Message too big */
 
+	if (data_out)
+		dest_cport_id = operation->connection->interface_cport_id;
+	else
+		dest_cport_id = CPORT_ID_BAD;
 	size += sizeof(*header);
-	gbuf = greybus_alloc_gbuf(operation, size, data_out, gfp_flags);
+	gbuf = greybus_alloc_gbuf(operation, dest_cport_id, size, gfp_flags);
 	if (!gbuf)
 		return NULL;