USB: gadget: Add EEM gadget driver
This patch adds a CDC EEM ethernet gadget driver. CDC EEM is a newer
USB ethernet specification that uses a simpler interface than the older
CDC ECM. This makes CDC EEM usable by a wider set of USB hardware.
By default the ethernet gadget will still use CDC ECM/Subset, but kernel
configuration and/or a module parameter will allow alternative use of
the CDC EEM protocol.
Changes since last version:
- Brought in missing RNDIS changes that caused compile error
- Modified 'sentinel CRC' checking to match EEM host driver
Signed-off-by: Brian Niebuhr <bniebuhr@efjohnson.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c
index c665219..f8751ff 100644
--- a/drivers/usb/gadget/u_ether.c
+++ b/drivers/usb/gadget/u_ether.c
@@ -37,8 +37,9 @@
* one (!) network link through the USB gadget stack, normally "usb0".
*
* The control and data models are handled by the function driver which
- * connects to this code; such as CDC Ethernet, "CDC Subset", or RNDIS.
- * That includes all descriptor and endpoint management.
+ * connects to this code; such as CDC Ethernet (ECM or EEM),
+ * "CDC Subset", or RNDIS. That includes all descriptor and endpoint
+ * management.
*
* Link level addressing is handled by this component using module
* parameters; if no such parameters are provided, random link level
@@ -68,9 +69,13 @@
struct list_head tx_reqs, rx_reqs;
atomic_t tx_qlen;
+ struct sk_buff_head rx_frames;
+
unsigned header_len;
- struct sk_buff *(*wrap)(struct sk_buff *skb);
- int (*unwrap)(struct sk_buff *skb);
+ struct sk_buff *(*wrap)(struct gether *, struct sk_buff *skb);
+ int (*unwrap)(struct gether *,
+ struct sk_buff *skb,
+ struct sk_buff_head *list);
struct work_struct work;
@@ -269,7 +274,7 @@
static void rx_complete(struct usb_ep *ep, struct usb_request *req)
{
- struct sk_buff *skb = req->context;
+ struct sk_buff *skb = req->context, *skb2;
struct eth_dev *dev = ep->driver_data;
int status = req->status;
@@ -278,26 +283,47 @@
/* normal completion */
case 0:
skb_put(skb, req->actual);
- if (dev->unwrap)
- status = dev->unwrap(skb);
- if (status < 0
- || ETH_HLEN > skb->len
- || skb->len > ETH_FRAME_LEN) {
- dev->net->stats.rx_errors++;
- dev->net->stats.rx_length_errors++;
- DBG(dev, "rx length %d\n", skb->len);
- break;
+
+ if (dev->unwrap) {
+ unsigned long flags;
+
+ spin_lock_irqsave(&dev->lock, flags);
+ if (dev->port_usb) {
+ status = dev->unwrap(dev->port_usb,
+ skb,
+ &dev->rx_frames);
+ } else {
+ dev_kfree_skb_any(skb);
+ status = -ENOTCONN;
+ }
+ spin_unlock_irqrestore(&dev->lock, flags);
+ } else {
+ skb_queue_tail(&dev->rx_frames, skb);
}
-
- skb->protocol = eth_type_trans(skb, dev->net);
- dev->net->stats.rx_packets++;
- dev->net->stats.rx_bytes += skb->len;
-
- /* no buffer copies needed, unless hardware can't
- * use skb buffers.
- */
- status = netif_rx(skb);
skb = NULL;
+
+ skb2 = skb_dequeue(&dev->rx_frames);
+ while (skb2) {
+ if (status < 0
+ || ETH_HLEN > skb2->len
+ || skb2->len > ETH_FRAME_LEN) {
+ dev->net->stats.rx_errors++;
+ dev->net->stats.rx_length_errors++;
+ DBG(dev, "rx length %d\n", skb2->len);
+ dev_kfree_skb_any(skb2);
+ goto next_frame;
+ }
+ skb2->protocol = eth_type_trans(skb2, dev->net);
+ dev->net->stats.rx_packets++;
+ dev->net->stats.rx_bytes += skb2->len;
+
+ /* no buffer copies needed, unless hardware can't
+ * use skb buffers.
+ */
+ status = netif_rx(skb2);
+next_frame:
+ skb2 = skb_dequeue(&dev->rx_frames);
+ }
break;
/* software-driven interface shutdown */
@@ -537,14 +563,15 @@
* or there's not enough space for extra headers we need
*/
if (dev->wrap) {
- struct sk_buff *skb_new;
+ unsigned long flags;
- skb_new = dev->wrap(skb);
- if (!skb_new)
+ spin_lock_irqsave(&dev->lock, flags);
+ if (dev->port_usb)
+ skb = dev->wrap(dev->port_usb, skb);
+ spin_unlock_irqrestore(&dev->lock, flags);
+ if (!skb)
goto drop;
- dev_kfree_skb_any(skb);
- skb = skb_new;
length = skb->len;
}
req->buf = skb->data;
@@ -578,9 +605,9 @@
}
if (retval) {
+ dev_kfree_skb_any(skb);
drop:
dev->net->stats.tx_dropped++;
- dev_kfree_skb_any(skb);
spin_lock_irqsave(&dev->req_lock, flags);
if (list_empty(&dev->tx_reqs))
netif_start_queue(net);
@@ -753,6 +780,8 @@
INIT_LIST_HEAD(&dev->tx_reqs);
INIT_LIST_HEAD(&dev->rx_reqs);
+ skb_queue_head_init(&dev->rx_frames);
+
/* network device setup */
dev->net = net;
strcpy(net->name, "usb%d");