/*
* f_ncm.c -- USB CDC Network (NCM) link function driver
*
* Copyright (C) 2010 Nokia Corporation
* Contact: Yauheni Kaliuta <yauheni.kaliuta@nokia.com>
*
* The driver borrows from f_ecm.c which is:
*
* Copyright (C) 2003-2005,2008 David Brownell
* Copyright (C) 2008 Nokia Corporation
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/etherdevice.h>
#include <linux/crc32.h>
#include <linux/usb/cdc.h>
#include "u_ether.h"
#include "u_ether_configfs.h"
#include "u_ncm.h"
/*
* This function is a "CDC Network Control Model" (CDC NCM) Ethernet link.
* NCM is intended to be used with high-speed network attachments.
*
* Note that NCM requires the use of "alternate settings" for its data
* interface. This means that the set_alt() method has real work to do,
* and also means that a get_alt() method is required.
*/
/* to trigger crc/non-crc ndp signature */
#define NCM_NDP_HDR_CRC_MASK 0x01000000
#define NCM_NDP_HDR_CRC 0x01000000
#define NCM_NDP_HDR_NOCRC 0x00000000
enum ncm_notify_state {
NCM_NOTIFY_NONE, /* don't notify */
NCM_NOTIFY_CONNECT, /* issue CONNECT next */
NCM_NOTIFY_SPEED, /* issue SPEED_CHANGE next */
};
struct f_ncm {
struct gether port;
u8 ctrl_id, data_id;
char ethaddr[14];
struct usb_ep *notify;
struct usb_request *notify_req;
u8 notify_state;
bool is_open;
const struct ndp_parser_opts *parser_opts;
bool is_crc;
u32 ndp_sign;
/*
* for notification, it is accessed from both
* callback and ethernet open/close
*/
spinlock_t lock;
struct net_device *netdev;
/* For multi-frame NDP TX */
struct sk_buff *skb_tx_data;
struct sk_buff *skb_tx_ndp;
u16 ndp_dgram_count;
bool timer_force_tx;
struct tasklet_struct tx_tasklet;
struct hrtimer task_timer;
bool timer_stopping;
};
static inline struct f_ncm *func_to_ncm(struct usb_function *f)
{
return container_of(f, struct f_ncm, port.func);
}
/* peak (theoretical) bulk transfer rate in bits-per-second */
static inline unsigned ncm_bitrate(struct usb_gadget *g)
{
if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
return 13 * 512 * 8 * 1000 * 8;
else
return 19 * 64 * 1 * 1000 * 8;
}
/*-------------------------------------------------------------------------*/
/*
* We cannot group frames so use just the minimal size which ok to put
* one max-size ethernet frame.
* If the host can group frames, allow it to do that, 16K is selected,
* because it's used by default by the current linux host driver
*/
#define NTB_DEFAULT_IN_SIZE 16384
#define NTB_OUT_SIZE 16384
/* Allocation for storing the NDP, 32 should suffice for a
* 16k packet. This allows a maximum of 32 * 507 Byte packets to
* be transmitted in a single 16kB skb, though when sending full size
* packets this limit will be plenty.
* Smaller packets are not likely to be trying to maximize the
* throughput and will be mstly sending smaller infrequent frames.
*/
#define TX_MAX_NUM_DPE 32
/* Delay for the transmit to wait before sending an unfilled NTB frame. */
#define TX_TIMEOUT_NSECS 300000
#define FORMATS_SUPPORTED (USB_CDC_NCM_NTB16_SUPPORTED | \
USB_CDC_NCM_NTB32_SUPPORTED)
static struct usb_cdc_ncm_ntb_parameters ntb_parameters = {
.wLength = cpu_to_le16(sizeof(ntb_parameters)),
.bmNtbFormatsSupported = cpu_to_le16(
| 