M7350/kernel/drivers/net/ethernet/msm/msm_rmnet_smux.c

/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

/*
 * RMNET SMUX Module.
 */
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/wakelock.h>
#include <linux/if_arp.h>
#include <linux/msm_rmnet.h>
#include <linux/platform_device.h>
#include <linux/smux.h>
#include <linux/ip.h>

#ifdef CONFIG_HAS_EARLYSUSPEND
#include <linux/earlysuspend.h>
#endif


/* Debug message support */
static int msm_rmnet_smux_debug_mask;
module_param_named(debug_enable, msm_rmnet_smux_debug_mask,
				   int, S_IRUGO | S_IWUSR | S_IWGRP);

#define DEBUG_MASK_LVL0 (1U << 0)
#define DEBUG_MASK_LVL1 (1U << 1)
#define DEBUG_MASK_LVL2 (1U << 2)

#define DBG(m, x...) do {			   \
		if (msm_rmnet_smux_debug_mask & m) \
			pr_info(x);		   \
} while (0)

#define DBG0(x...) DBG(DEBUG_MASK_LVL0, x)
#define DBG1(x...) DBG(DEBUG_MASK_LVL1, x)
#define DBG2(x...) DBG(DEBUG_MASK_LVL2, x)

/* Configure device instances */
#define RMNET_SMUX_DEVICE_COUNT (2)

/* allow larger frames */
#define RMNET_DATA_LEN 2000

#define DEVICE_ID_INVALID   -1

#define DEVICE_INACTIVE     0x00
#define DEVICE_ACTIVE       0x01

#define HEADROOM_FOR_SMUX    8 /* for mux header */
#define HEADROOM_FOR_QOS     8
#define TAILROOM             8 /* for padding by mux layer */

struct rmnet_private {
	struct net_device_stats stats;
	uint32_t ch_id;
#ifdef CONFIG_MSM_RMNET_DEBUG
	ktime_t last_packet;
	unsigned long wakeups_xmit;
	unsigned long wakeups_rcv;
	unsigned long timeout_us;
#endif
	spinlock_t lock;
	spinlock_t tx_queue_lock;
	struct tasklet_struct tsklt;
	/* IOCTL specified mode (protocol, QoS header) */
	u32 operation_mode;
	uint8_t device_state;
	uint8_t in_reset;
};

static struct net_device *netdevs[RMNET_SMUX_DEVICE_COUNT];

#ifdef CONFIG_MSM_RMNET_DEBUG
static unsigned long timeout_us;

#ifdef CONFIG_HAS_EARLYSUSPEND
/*
 * If early suspend is enabled then we specify two timeout values,
 * screen on (default), and screen is off.
 */
static unsigned long timeout_suspend_us;
static struct device *rmnet0;

/* Set timeout in us when the screen is off. */
static ssize_t timeout_suspend_store(struct device *d,
				     struct device_attribute *attr,
				     const char *buf, size_t n)
{
	timeout_suspend_us = strict_strtoul(buf, NULL, 10);
	return n;
}

static ssize_t timeout_suspend_show(struct device *d,
				    struct device_attribute *attr,
				    char *buf)
{
	return snprintf(buf, PAGE_SIZE, "%lu\n",
			(unsigned long) timeout_suspend_us);
}

static DEVICE_ATTR(timeout_suspend, 0664, timeout_suspend_show,
				   timeout_suspend_store);

static void rmnet_early_suspend(struct early_suspend *handler)
{
	if (rmnet0) {
		struct rmnet_private *p = netdev_priv(to_net_dev(rmnet0));
		p->timeout_us = timeout_suspend_us;
	}
}

static void rmnet_late_resume(struct early_suspend *handler)
{
	if (rmnet0) {
		struct rmnet_private *p = netdev_priv(to_net_dev(rmnet0));
		p->timeout_us = timeout_us;
	}
}

static struct early_suspend rmnet_power_suspend = {
	.suspend = rmnet_early_suspend,
	.resume = rmnet_late_resume,
};

static int __init rmnet_late_init(void)
{
	register_early_suspend(&rmnet_power_suspend);
	return 0;
}

late_initcall(rmnet_late_init);
#endif /* CONFIG_HAS_EARLYSUSPEND */

/* Returns 1 if packet caused rmnet to wakeup, 0 otherwise. */
static int rmnet_cause_wakeup(struct rmnet_private *p)
{
	int ret = 0;
	ktime_t now;
	if (p->timeout_us == 0)	/* Check if disabled */
		return 0;

	/* Use real (wall) time. */
	now = ktime_get_real();

	if (ktime_us_delta(now, p->last_packet) > p->timeout_us)
		ret = 1;

	p->last_packet = now;
	return ret;
}

static ssize_t wakeups_xmit_show(struct device *d,
				 struct device_attribute *attr,
				 char *buf)
{
	struct rmnet_private *p = netdev_priv(to_net_dev(d));
	return snprintf(buf, PAGE_SIZE, "%lu\n", p->wakeups_xmit);
}

DEVICE_ATTR(wakeups_xmit, 0444, wakeups_xmit_show, NULL);

static ssize_t wakeups_rcv_show(struct device *d,
				struct device_attribute *attr,
				char *buf)
{
	struct rmnet_private *p = netdev_priv(to_net_dev(d));
	return snprintf(buf, PAGE_SIZE, "%lu\n", p->wakeups_rcv);
}

DEVICE_ATTR(wakeups_rcv, 0444, wakeups_rcv_show, NULL);

/* Set timeout in us. */
static ssize_t timeout_store(struct device *d,
			     struct device_attribute *attr,
			     const char *buf, size_t n)
{
#ifndef CONFIG_HAS_EARLYSUSPEND
	struct rmnet_private *p = netdev_priv(to_net_dev(d));
	p->timeout_us = timeout_us = strict_strtoul(buf, NULL, 10);
#else
/* If using early suspend/resume hooks do not write the value on store. */
	timeout_us = strict_strtoul(buf, NULL, 10);
#endif /* CONFIG_HAS_EARLYSUSPEND */
	return n;
}

static ssize_t timeout_show(struct device *d,
			    struct device_attribute *attr,
			    char *buf)
{
	struct rmnet_private *p = netdev_priv(to_net_dev(d));
	p = netdev_priv(to_net_dev(d));
	return snprintf(buf, PAGE_SIZE, "%lu\n", timeout_us);
}

DEVICE_ATTR(timeout, 0664, timeout_show, timeout_store);
#endif /* CONFIG_MSM_RMNET_DEBUG */

/* Forward declaration */
static int rmnet_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd);




static int count_this_packet(void *_hdr, int len)
{
	struct ethhdr *hdr = _hdr;

	if (len >= ETH_HLEN && hdr->h_proto == htons(ETH_P_ARP))
		return 0;

	return 1;
}

static __be16 rmnet_ip_type_trans(struct sk_buff *skb, struct net_device *dev)
{
	__be16 protocol = 0;

	skb->dev = dev;

	/* Determine L3 protocol */
	switch (skb->data[0] & 0xf0) {
	case 0x40:
		protocol = htons(ETH_P_IP);
		break;
	case 0x60:
		protocol = htons(ETH_P_IPV6);
		break;
	default:
		pr_err("[%s] rmnet_recv() L3 protocol decode error: 0x%02x",
			   dev->name, skb->data[0] & 0xf0);
		/* skb will be dropped in upper layer for unknown protocol */
	}
	return protocol;
}

static void smux_read_done(void *rcv_dev, const void *meta_data)
{
	struct rmnet_private *p;
	struct net_device *dev = rcv_dev;
	u32 opmode;
	unsigned long flags;
	struct sk_buff *skb = NULL;
	const struct smux_meta_read  *read_meta_info = meta_data;

	if (!dev || !read_meta_info) {
		DBG1("%s:invalid read_done callback recieved", __func__);
		return;
	}

	p = netdev_priv(dev);

	skb = (struct sk_buff *) read_meta_info->pkt_priv;

	if (!skb || skb->dev != dev) {
		DBG1("%s: ERR:skb pointer NULL in READ_DONE CALLBACK",
		      __func__);
		return;
	}

	/* Handle Rx frame format */
	spin_lock_irqsave(&p->lock, flags);
	opmode = p->operation_mode;
	spin_unlock_irqrestore(&p->lock, flags);

	if (RMNET_IS_MODE_IP(opmode)) {
		/* Driver in IP mode */
		skb->protocol =
		rmnet_ip_type_trans(skb, dev);
	} else {
		/* Driver in Ethernet mode */
		skb->protocol =
		eth_type_trans(skb, dev);
	}
	if (RMNET_IS_MODE_IP(opmode) ||
		count_this_packet(skb->data, skb->len)) {
#ifdef CONFIG_MSM_RMNET_DEBUG
		p->wakeups_rcv +=
		rmnet_cause_wakeup(p);
#endif
		p->stats.rx_packets++;
		p->stats.rx_bytes += skb->len;
	}
	DBG2("[%s] Rx packet #%lu len=%d\n",
		 dev->name, p->stats.rx_packets,
		 skb->len);
	/* Deliver to network stack */
	netif_rx(skb);

	return;
}

static void smux_write_done(void *dev, const void *meta_data)
{
	struct rmnet_private *p = netdev_priv(dev);
	u32 opmode;
	struct sk_buff *skb = NULL;
	const struct smux_meta_write  *write_meta_info = meta_data;
	unsigned long flags;

	if (!dev || !write_meta_info) {
		DBG1("%s: ERR:invalid WRITE_DONE callback recieved", __func__);
		return;
	}

	skb = (struct sk_buff *) write_meta_info->pkt_priv;

	if (!skb) {
		DBG1("%s: ERR:skb pointer NULL in WRITE_DONE"
		     " CALLBACK", __func__);
		return;
	}

	spin_lock_irqsave(&p->lock, flags);
	opmode = p->operation_mode;
	spin_unlock_irqrestore(&p->lock, flags);

	DBG1("%s: write complete\n", __func__);
	if (RMNET_IS_MODE_IP(opmode) ||
		count_this_packet(skb->data, skb->len)) {
		p->stats.tx_packets++;
		p->stats.tx_bytes += skb->len;
#ifdef CONFIG_MSM_RMNET_DEBUG
		p->wakeups_xmit += rmnet_cause_wakeup(p);
#endif
	}
	DBG1("[%s] Tx packet #%lu len=%d mark=0x%x\n",
		 ((struct net_device *)(dev))->name, p->stats.tx_packets,
		 skb->len, skb->mark);
	dev_kfree_skb_any(skb);

	spin_lock_irqsave(&p->tx_queue_lock, flags);
	if (netif_queue_stopped(dev) &&
		msm_smux_is_ch_low(p->ch_id)) {
		DBG0("%s: Low WM hit, waking queue=%p\n",
			 __func__, skb);
		netif_wake_queue(dev);
	}
	spin_unlock_irqrestore(&p->tx_queue_lock, flags);
}

void rmnet_smux_notify(void *priv, int event_type, const void *metadata)
{
	struct rmnet_private *p;
	struct net_device *dev;
	unsigned long flags;
	struct sk_buff *skb = NULL;
	u32 opmode;
	const struct smux_meta_disconnected *ssr_info;
	const struct smux_meta_read *read_meta_info;
	const struct smux_meta_write *write_meta_info = metadata;


	if (!priv)
		DBG0("%s: priv(cookie) NULL, ignoring notification:"
		     " %d\n", __func__, event_type);

	switch (event_type) {
	case SMUX_CONNECTED:
		p = netdev_priv(priv);
		dev = priv;

		DBG0("[%s] SMUX_CONNECTED event dev:%s\n", __func__, dev->name);

		netif_carrier_on(dev);
		netif_start_queue(dev);

		spin_lock_irqsave(&p->lock, flags);
		p->device_state = DEVICE_ACTIVE;
		spin_unlock_irqrestore(&p->lock, flags);
		break;

	case SMUX_DISCONNECTED:
		p = netdev_priv(priv);
		dev = priv;
		ssr_info = metadata;

		DBG0("[%s] SMUX_DISCONNECTED event dev:%s\n",
		      __func__, dev->name);

		if (ssr_info && ssr_info->is_ssr == 1)
			DBG0("SSR detected on :%s\n", dev->name);

		netif_carrier_off(dev);
		netif_stop_queue(dev);

		spin_lock_irqsave(&p->lock, flags);
		p->device_state = DEVICE_INACTIVE;
		spin_unlock_irqrestore(&p->lock, flags);
		break;

	case SMUX_READ_DONE:
		smux_read_done(priv, metadata);
		break;

	case SMUX_READ_FAIL:
		p = netdev_priv(priv);
		dev = priv;
		read_meta_info = metadata;

		if (!dev || !read_meta_info) {
			DBG1("%s: ERR:invalid read failed callback"
			     " recieved", __func__);
			return;
		}

		skb = (struct sk_buff *) read_meta_info->pkt_priv;

		if (!skb) {
			DBG1("%s: ERR:skb pointer NULL in read fail"
			     " CALLBACK", __func__);
			return;
		}

		DBG0("%s: read failed\n", __func__);

		opmode = p->operation_mode;

		if (RMNET_IS_MODE_IP(opmode) ||
		    count_this_packet(skb->data, skb->len))
			p->stats.rx_dropped++;

		dev_kfree_skb_any(skb);
		break;

	case SMUX_WRITE_DONE:
		smux_write_done(priv, metadata);
		break;

	case SMUX_WRITE_FAIL:
		p = netdev_priv(priv);
		dev = priv;
		write_meta_info = metadata;

		if (!dev || !write_meta_info) {
			DBG1("%s: ERR:invalid WRITE_DONE"
			     "callback recieved", __func__);
			return;
		}

		skb = (struct sk_buff *) write_meta_info->pkt_priv;

		if (!skb) {
			DBG1("%s: ERR:skb pointer NULL in"
			     " WRITE_DONE CALLBACK", __func__);
			return;
		}

		DBG0("%s: write failed\n", __func__);

		opmode = p->operation_mode;

		if (RMNET_IS_MODE_IP(opmode) ||
		    count_this_packet(skb->data, skb->len)) {
			p->stats.tx_dropped++;
		}

		dev_kfree_skb_any(skb);
		break;

	case SMUX_LOW_WM_HIT:
		dev = priv;
		p = netdev_priv(priv);
		DBG0("[%s] Low WM hit dev:%s\n", __func__, dev->name);
		spin_lock_irqsave(&p->tx_queue_lock, flags);
		netif_wake_queue(dev);
		spin_unlock_irqrestore(&p->tx_queue_lock, flags);
		break;

	case SMUX_HIGH_WM_HIT:
		dev = priv;
		p = netdev_priv(priv);
		DBG0("[%s] High WM hit dev:%s\n", __func__, dev->name);
		spin_lock_irqsave(&p->tx_queue_lock, flags);
		netif_stop_queue(dev);
		spin_unlock_irqrestore(&p->tx_queue_lock, flags);
		break;

	default:
		dev = priv;
		DBG0("[%s] Invalid event:%d received on"
		     " dev: %s\n", __func__, event_type, dev->name);
		break;
	}

	return;
}

int get_rx_buffers(void *priv, void **pkt_priv, void **buffer, int size)
{
	struct net_device *dev = (struct net_device *) priv;
	struct sk_buff *skb = NULL;
	void *ptr = NULL;

	DBG0("[%s] dev:%s\n", __func__, dev->name);
	skb = __dev_alloc_skb(size, GFP_ATOMIC);
	if (skb == NULL) {
		DBG0("%s: unable to alloc skb\n", __func__);
		return -ENOMEM;
	}

	/* TODO skb_reserve(skb, NET_IP_ALIGN); for ethernet mode */
	/* Populate some params now. */
	skb->dev = dev;
	ptr = skb_put(skb, size);

	skb_set_network_header(skb, 0);

	/* done with skb setup, return the buffer pointer. */
	*pkt_priv = skb;
	*buffer = ptr;

	return 0;
}

static int __rmnet_open(struct net_device *dev)
{
	struct rmnet_private *p = netdev_priv(dev);

	DBG0("[%s] __rmnet_open()\n", dev->name);

	if (p->device_state == DEVICE_ACTIVE) {
		return 0;
	} else {
		DBG0("[%s] Platform inactive\n", dev->name);
		return -ENODEV;
	}
}

static int rmnet_open(struct net_device *dev)
{
	int rc = 0;

	DBG0("[%s] rmnet_open()\n", dev->name);

	rc = __rmnet_open(dev);

	if (rc == 0)
		netif_start_queue(dev);

	return rc;
}

static int rmnet_stop(struct net_device *dev)
{
	DBG0("[%s] rmnet_stop()\n", dev->name);

	netif_stop_queue(dev);
	return 0;
}

static int rmnet_change_mtu(struct net_device *dev, int new_mtu)
{
	if (0 > new_mtu || RMNET_DATA_LEN < new_mtu)
		return -EINVAL;

	DBG0("[%s] MTU change: old=%d new=%d\n",
		 dev->name, dev->mtu, new_mtu);
	dev->mtu = new_mtu;

	return 0;
}

static int _rmnet_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct rmnet_private *p = netdev_priv(dev);
	struct QMI_QOS_HDR_S *qmih;
	u32 opmode;
	unsigned long flags;

	/* For QoS mode, prepend QMI header and assign flow ID from skb->mark */
	spin_lock_irqsave(&p->lock, flags);
	opmode = p->operation_mode;
	spin_unlock_irqrestore(&p->lock, flags);

	if (RMNET_IS_MODE_QOS(opmode)) {
		qmih = (struct QMI_QOS_HDR_S *)
			   skb_push(skb, sizeof(struct QMI_QOS_HDR_S));
		qmih->version = 1;
		qmih->flags = 0;
		qmih->flow_id = skb->mark;
	}

	dev->trans_start = jiffies;

	return msm_smux_write(p->ch_id, skb, skb->data, skb->len);
}

static int rmnet_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct rmnet_private *p = netdev_priv(dev);
	unsigned long flags;
	int ret = 0;

	if (netif_queue_stopped(dev) || (p->device_state == DEVICE_INACTIVE)) {
		pr_err("[%s]fatal: rmnet_xmit called when "
			   "netif_queue is stopped", dev->name);
		return 0;
	}

	spin_lock_irqsave(&p->tx_queue_lock, flags);
	ret = _rmnet_xmit(skb, dev);

	if (ret == -EAGAIN) {
		/*
		 * EAGAIN means we attempted to overflow the high watermark
		 * Clearly the queue is not stopped like it should be, so
		 * stop it and return BUSY to the TCP/IP framework.  It will
		 * retry this packet with the queue is restarted which happens
		 * low watermark is called.
		 */
		netif_stop_queue(dev);
		ret = NETDEV_TX_BUSY;
	}
	spin_unlock_irqrestore(&p->tx_queue_lock, flags);

	return ret;
}

static struct net_device_stats *rmnet_get_stats(struct net_device *dev)
{
	struct rmnet_private *p = netdev_priv(dev);
	return &p->stats;
}

static void rmnet_tx_timeout(struct net_device *dev)
{
	pr_warning("[%s] rmnet_tx_timeout()\n", dev->name);
}

static const struct net_device_ops rmnet_ops_ether = {
	.ndo_open = rmnet_open,
	.ndo_stop = rmnet_stop,
	.ndo_start_xmit = rmnet_xmit,
	.ndo_get_stats = rmnet_get_stats,
	.ndo_tx_timeout = rmnet_tx_timeout,
	.ndo_do_ioctl = rmnet_ioctl,
	.ndo_change_mtu = rmnet_change_mtu,
	.ndo_set_mac_address = eth_mac_addr,
	.ndo_validate_addr = eth_validate_addr,
};

static const struct net_device_ops rmnet_ops_ip = {
	.ndo_open = rmnet_open,
	.ndo_stop = rmnet_stop,
	.ndo_start_xmit = rmnet_xmit,
	.ndo_get_stats = rmnet_get_stats,
	.ndo_tx_timeout = rmnet_tx_timeout,
	.ndo_do_ioctl = rmnet_ioctl,
	.ndo_change_mtu = rmnet_change_mtu,
	.ndo_set_mac_address = 0,
	.ndo_validate_addr = 0,
};

static int rmnet_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
	struct rmnet_private *p = netdev_priv(dev);
	u32 old_opmode = p->operation_mode;
	unsigned long flags;
	int prev_mtu = dev->mtu;
	int rc = 0;

	/* Process IOCTL command */
	switch (cmd) {
	case RMNET_IOCTL_SET_LLP_ETHERNET:	/* Set Ethernet protocol   */
		/* Perform Ethernet config only if in IP mode currently*/
		if (p->operation_mode & RMNET_MODE_LLP_IP) {
			ether_setup(dev);
			random_ether_addr(dev->dev_addr);
			dev->mtu = prev_mtu;

			dev->netdev_ops = &rmnet_ops_ether;
			spin_lock_irqsave(&p->lock, flags);
			p->operation_mode &= ~RMNET_MODE_LLP_IP;
			p->operation_mode |= RMNET_MODE_LLP_ETH;
			spin_unlock_irqrestore(&p->lock, flags);
			DBG0("[%s] rmnet_ioctl(): "
				 "set Ethernet protocol mode\n",
				 dev->name);
		}
		break;

	case RMNET_IOCTL_SET_LLP_IP:		/* Set RAWIP protocol      */
		/* Perform IP config only if in Ethernet mode currently*/
		if (p->operation_mode & RMNET_MODE_LLP_ETH) {

			/* Undo config done in ether_setup() */
			dev->header_ops         = 0;  /* No header */
			dev->type               = ARPHRD_RAWIP;
			dev->hard_header_len    = 0;
			dev->mtu                = prev_mtu;
			dev->addr_len           = 0;
			dev->flags              &= ~(IFF_BROADCAST |
						     IFF_MULTICAST);

			dev->needed_headroom = HEADROOM_FOR_SMUX +
							HEADROOM_FOR_QOS;
			dev->needed_tailroom = TAILROOM;
			dev->netdev_ops = &rmnet_ops_ip;
			spin_lock_irqsave(&p->lock, flags);
			p->operation_mode &= ~RMNET_MODE_LLP_ETH;
			p->operation_mode |= RMNET_MODE_LLP_IP;
			spin_unlock_irqrestore(&p->lock, flags);
			DBG0("[%s] rmnet_ioctl(): "
				 "set IP protocol mode\n",
				 dev->name);
		}
		break;

	case RMNET_IOCTL_GET_LLP:	/* Get link protocol state */
		ifr->ifr_ifru.ifru_data =
		(void *)(p->operation_mode &
				 (RMNET_MODE_LLP_ETH|RMNET_MODE_LLP_IP));
		break;

	case RMNET_IOCTL_SET_QOS_ENABLE:	/* Set QoS header enabled */
		spin_lock_irqsave(&p->lock, flags);
		p->operation_mode |= RMNET_MODE_QOS;
		spin_unlock_irqrestore(&p->lock, flags);
		DBG0("[%s] rmnet_ioctl(): set QMI QOS header enable\n",
			 dev->name);
		break;

	case RMNET_IOCTL_SET_QOS_DISABLE:	/* Set QoS header disabled */
		spin_lock_irqsave(&p->lock, flags);
		p->operation_mode &= ~RMNET_MODE_QOS;
		spin_unlock_irqrestore(&p->lock, flags);
		DBG0("[%s] rmnet_ioctl(): set QMI QOS header disable\n",
			 dev->name);
		break;

	case RMNET_IOCTL_GET_QOS:	/* Get QoS header state */
		ifr->ifr_ifru.ifru_data =
		(void *)(p->operation_mode & RMNET_MODE_QOS);
		break;

	case RMNET_IOCTL_GET_OPMODE:	/* Get operation mode */
		ifr->ifr_ifru.ifru_data = (void *)p->operation_mode;
		break;

	case RMNET_IOCTL_OPEN:		/* Open transport port */
		rc = __rmnet_open(dev);
		DBG0("[%s] rmnet_ioctl(): open transport port\n",
			 dev->name);
		break;

	case RMNET_IOCTL_CLOSE:		/* Close transport port */
		DBG0("[%s] rmnet_ioctl(): close transport port\n",
			 dev->name);
		break;

	default:
		pr_err("[%s] error: rmnet_ioct called for unsupported cmd[%d]",
			   dev->name, cmd);
		return -EINVAL;
	}

	DBG2("[%s] %s: cmd=0x%x opmode old=0x%08x new=0x%08x\n",
		 dev->name, __func__, cmd, old_opmode, p->operation_mode);
	return rc;
}

static void __init rmnet_setup(struct net_device *dev)
{
	/* Using Ethernet mode by default */
	dev->netdev_ops = &rmnet_ops_ether;
	ether_setup(dev);

	/* set this after calling ether_setup */
	dev->mtu = RMNET_DATA_LEN;
	dev->needed_headroom = HEADROOM_FOR_SMUX + HEADROOM_FOR_QOS ;
	dev->needed_tailroom = TAILROOM;
	random_ether_addr(dev->dev_addr);

	dev->watchdog_timeo = 1000;	/* 10 seconds? */
}


static int smux_rmnet_probe(struct platform_device *pdev)
{
	int i;
	int r;
	struct rmnet_private *p;

	for (i = 0; i < RMNET_SMUX_DEVICE_COUNT; i++) {
		p = netdev_priv(netdevs[i]);

		if (p != NULL) {
			r =  msm_smux_open(p->ch_id,
					   netdevs[i],
					   rmnet_smux_notify,
					   get_rx_buffers);

			if (r < 0) {
				DBG0("%s: ch=%d open failed with rc %d\n",
				      __func__, p->ch_id, r);
			}
		}
	}
	return 0;
}

static int smux_rmnet_remove(struct platform_device *pdev)
{
	int i;
	int r;
	struct rmnet_private *p;

	for (i = 0; i < RMNET_SMUX_DEVICE_COUNT; i++) {
		p = netdev_priv(netdevs[i]);

		if (p != NULL) {
			r =  msm_smux_close(p->ch_id);

			if (r < 0) {
				DBG0("%s: ch=%d close failed with rc %d\n",
				     __func__, p->ch_id, r);
				continue;
			}
			netif_carrier_off(netdevs[i]);
			netif_stop_queue(netdevs[i]);
		}
	}
	return 0;
}


static struct platform_driver smux_rmnet_driver = {
	.probe  = smux_rmnet_probe,
	.remove = smux_rmnet_remove,
	.driver = {
		.name = "SMUX_RMNET",
		.owner = THIS_MODULE,
	},
};


static int __init rmnet_init(void)
{
	int ret;
	struct device *d;
	struct net_device *dev;
	struct rmnet_private *p;
	unsigned n;

#ifdef CONFIG_MSM_RMNET_DEBUG
	timeout_us = 0;
#ifdef CONFIG_HAS_EARLYSUSPEND
	timeout_suspend_us = 0;
#endif /* CONFIG_HAS_EARLYSUSPEND */
#endif /* CONFIG_MSM_RMNET_DEBUG */

	for (n = 0; n < RMNET_SMUX_DEVICE_COUNT; n++) {
		dev = alloc_netdev(sizeof(struct rmnet_private),
				   "rmnet_smux%d", rmnet_setup);

		if (!dev) {
			pr_err("%s: no memory for netdev %d\n", __func__, n);
			return -ENOMEM;
		}

		netdevs[n] = dev;
		d = &(dev->dev);
		p = netdev_priv(dev);
		/* Initial config uses Ethernet */
		p->operation_mode = RMNET_MODE_LLP_ETH;
		p->ch_id = n;
		p->in_reset = 0;
		spin_lock_init(&p->lock);
		spin_lock_init(&p->tx_queue_lock);
#ifdef CONFIG_MSM_RMNET_DEBUG
		p->timeout_us = timeout_us;
		p->wakeups_xmit = p->wakeups_rcv = 0;
#endif

		ret = register_netdev(dev);
		if (ret) {
			pr_err("%s: unable to register netdev"
				   " %d rc=%d\n", __func__, n, ret);
			free_netdev(dev);
			return ret;
		}

#ifdef CONFIG_MSM_RMNET_DEBUG
		if (device_create_file(d, &dev_attr_timeout))
			continue;
		if (device_create_file(d, &dev_attr_wakeups_xmit))
			continue;
		if (device_create_file(d, &dev_attr_wakeups_rcv))
			continue;
#ifdef CONFIG_HAS_EARLYSUSPEND
		if (device_create_file(d, &dev_attr_timeout_suspend))
			continue;

		/* Only care about rmnet0 for suspend/resume tiemout hooks. */
		if (n == 0)
			rmnet0 = d;
#endif /* CONFIG_HAS_EARLYSUSPEND */
#endif /* CONFIG_MSM_RMNET_DEBUG */

	}

	ret = platform_driver_register(&smux_rmnet_driver);
	if (ret) {
		pr_err("%s: registration failed n=%d rc=%d\n",
			   __func__, n, ret);
		return ret;
	}
	return 0;
}

module_init(rmnet_init);
MODULE_DESCRIPTION("MSM RMNET SMUX TRANSPORT");
MODULE_LICENSE("GPL v2");