path: root/drivers/net/usb/cdc_ncm.c

/*
 * cdc_ncm.c
 *
 * Copyright (C) ST-Ericsson 2010-2012
 * Contact: Alexey Orishko <alexey.orishko@stericsson.com>
 * Original author: Hans Petter Selasky <hans.petter.selasky@stericsson.com>
 *
 * USB Host Driver for Network Control Model (NCM)
 * http://www.usb.org/developers/devclass_docs/NCM10.zip
 *
 * The NCM encoding, decoding and initialization logic
 * derives from FreeBSD 8.x. if_cdce.c and if_cdcereg.h
 *
 * This software is available to you under a choice of one of two
 * licenses. You may choose this file to be licensed under the terms
 * of the GNU General Public License (GPL) Version 2 or the 2-clause
 * BSD license listed below:
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/ctype.h>
#include <linux/ethtool.h>
#include <linux/workqueue.h>
#include <linux/mii.h>
#include <linux/crc32.h>
#include <linux/usb.h>
#include <linux/hrtimer.h>
#include <linux/atomic.h>
#include <linux/usb/usbnet.h>
#include <linux/usb/cdc.h>
#include <linux/usb/cdc_ncm.h>

#if IS_ENABLED(CONFIG_USB_NET_CDC_MBIM)
static bool prefer_mbim = true;
#else
static bool prefer_mbim;
#endif
module_param(prefer_mbim, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(prefer_mbim, "Prefer MBIM setting on dual NCM/MBIM functions");

static void cdc_ncm_txpath_bh(unsigned long param);
static void cdc_ncm_tx_timeout_start(struct cdc_ncm_ctx *ctx);
static enum hrtimer_restart cdc_ncm_tx_timer_cb(struct hrtimer *hr_timer);
static struct usb_driver cdc_ncm_driver;

static u8 cdc_ncm_setup(struct usbnet *dev)
{
	struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0];
	struct usb_cdc_ncm_ntb_parameters ncm_parm;
	u32 val;
	u8 flags;
	u8 iface_no;
	int err;
	int eth_hlen;
	u16 ntb_fmt_supported;
	u32 min_dgram_size;
	u32 min_hdr_size;

	iface_no = ctx->control->cur_altsetting->desc.bInterfaceNumber;

	err = usbnet_read_cmd(dev, USB_CDC_GET_NTB_PARAMETERS,
			      USB_TYPE_CLASS | USB_DIR_IN
			      |USB_RECIP_INTERFACE,
			      0, iface_no, &ncm_parm,
			      sizeof(ncm_parm));
	if (err < 0) {
		dev_dbg(&dev->intf->dev, "failed GET_NTB_PARAMETERS\n");
		return 1;
	}

	/* read correct set of parameters according to device mode */
	ctx->rx_max = le32_to_cpu(ncm_parm.dwNtbInMaxSize);
	ctx->tx_max = le32_to_cpu(ncm_parm.dwNtbOutMaxSize);
	ctx->tx_remainder = le16_to_cpu(ncm_parm.wNdpOutPayloadRemainder);
	ctx->tx_modulus = le16_to_cpu(ncm_parm.wNdpOutDivisor);
	ctx->tx_ndp_modulus = le16_to_cpu(ncm_parm.wNdpOutAlignment);
	/* devices prior to NCM Errata shall set this field to zero */
	ctx->tx_max_datagrams = le16_to_cpu(ncm_parm.wNtbOutMaxDatagrams);
	ntb_fmt_supported = le16_to_cpu(ncm_parm.bmNtbFormatsSupported);

	eth_hlen = ETH_HLEN;
	min_dgram_size = CDC_NCM_MIN_DATAGRAM_SIZE;