From: Yauheni Kaliuta <yauheni.kaliuta@xxxxxxxxx> 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: Yauheni Kaliuta <yauheni.kaliuta@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxx> --- drivers/usb/gadget/u_ether.c | 14 ++++++++++++-- drivers/usb/gadget/u_ether.h | 4 ++++ 2 files changed, 16 insertions(+), 2 deletions(-) diff --git a/drivers/usb/gadget/u_ether.c b/drivers/usb/gadget/u_ether.c index cb23355..a7826a6 100644 --- a/drivers/usb/gadget/u_ether.c +++ b/drivers/usb/gadget/u_ether.c @@ -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; diff --git a/drivers/usb/gadget/u_ether.h b/drivers/usb/gadget/u_ether.h index 3c8c0c9..7521970 100644 --- a/drivers/usb/gadget/u_ether.h +++ b/drivers/usb/gadget/u_ether.h @@ -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, -- 1.7.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
