Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 5c1168db authored by Yauheni Kaliuta's avatar Yauheni Kaliuta Committed by Greg Kroah-Hartman
Browse files

usb: gadget: u_ether: prepare for NCM 

NCM is a Network Control Model, subclass of USB CDC class,
specification is available at http://www.usb.org/developers/devclass_docs



This patch makes possible for u_ether to use multiply of wMaxPacketSize
predefined size transfers without ZLP (Zero Length Packet), required
by NCM spec.

Signed-off-by: default avatarYauheni Kaliuta <yauheni.kaliuta@nokia.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent ff176a4e

drivers/usb/gadget/u_ether.c

+12 −2
Original line number Diff line number Diff line
@@ -240,6 +240,9 @@ rx_submit(struct eth_dev *dev, struct usb_request *req, gfp_t gfp_flags) 
	size += out->maxpacket - 1;

	size -= size % out->maxpacket;



	if (dev->port_usb->is_fixed)

		size = max(size, dev->port_usb->fixed_out_len);



	skb = alloc_skb(size + NET_IP_ALIGN, gfp_flags);

	if (skb == NULL) {

		DBG(dev, "no rx skb\n");
@@ -578,12 +581,19 @@ static netdev_tx_t eth_start_xmit(struct sk_buff *skb, 
	req->context = skb;

	req->complete = tx_complete;



	/* NCM requires no zlp if transfer is dwNtbInMaxSize */

	if (dev->port_usb->is_fixed &&

	    length == dev->port_usb->fixed_in_len &&

	    (length % in->maxpacket) == 0)

		req->zero = 0;

	else

		req->zero = 1;



	/* use zlp framing on tx for strict CDC-Ether conformance,

	 * though any robust network rx path ignores extra padding.

	 * and some hardware doesn't like to write zlps.

	 */

	req->zero = 1;

	if (!dev->zlp && (length % in->maxpacket) == 0)

	if (req->zero && !dev->zlp && (length % in->maxpacket) == 0)

		length++;



	req->length = length;

drivers/usb/gadget/u_ether.h

+4 −0
Original line number Diff line number Diff line
@@ -62,6 +62,10 @@ struct gether { 


	/* hooks for added framing, as needed for RNDIS and EEM. */

	u32				header_len;

	/* NCM requires fixed size bundles */

	bool				is_fixed;

	u32				fixed_out_len;

	u32				fixed_in_len;

	struct sk_buff			*(*wrap)(struct gether *port,

						struct sk_buff *skb);

	int				(*unwrap)(struct gether *port,