staging: gdm72xx: Add GCT GDM72xx WiMAX driver.

This patch provides the kernel driver for the GDM72xx WiMAX chips
developed by GCT Semiconductor, Inc., which enables mobile WiMAX
connection on the Linux host.

Signed-off-by: Sage Ahn <syahn@gctsemi.com>
Cc: Ben Chan <benchan@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 804 insertions, 0 deletions

diff --git a/drivers/staging/gdm72xx/gdm_usb.c b/drivers/staging/gdm72xx/gdm_usb.c
new file mode 100644
index 000000000000..004786bae577
--- /dev/null
+++ b/drivers/staging/gdm72xx/gdm_usb.c
@@ -0,0 +1,804 @@
+/*
+ * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#include <linux/module.h>
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/usb.h>
+#include <asm/byteorder.h>
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+#ifndef CONFIG_USB_SUSPEND
+#error "USB host doesn't support USB Selective Suspend."
+#endif
+#endif
+
+#include "gdm_usb.h"
+#include "gdm_wimax.h"
+#include "usb_boot.h"
+#include "hci.h"
+
+#include "usb_ids.h"
+
+MODULE_DEVICE_TABLE(usb, id_table);
+
+#define TX_BUF_SIZE	2048
+#if defined(CONFIG_WIMAX_GDM72XX_WIMAX2)
+#define RX_BUF_SIZE	(128*1024)	/* For packet aggregation */
+#else
+#define RX_BUF_SIZE	2048
+#endif
+
+#define GDM7205_PADDING		256
+
+#define H2B(x)		__cpu_to_be16(x)
+#define B2H(x)		__be16_to_cpu(x)
+#define DB2H(x)		__be32_to_cpu(x)
+
+#define DOWNLOAD_CONF_VALUE		0x21
+
+#ifdef CONFIG_WIMAX_GDM72XX_K_MODE
+
+static DECLARE_WAIT_QUEUE_HEAD(k_wait);
+static LIST_HEAD(k_list);
+static DEFINE_SPINLOCK(k_lock);
+static int k_mode_stop;
+
+#define K_WAIT_TIME	(2 * HZ / 100)
+
+#endif /* CONFIG_WIMAX_GDM72XX_K_MODE */
+
+static int init_usb(struct usbwm_dev *udev);
+static void release_usb(struct usbwm_dev *udev);
+
+/*#define DEBUG */
+#ifdef DEBUG
+static void hexdump(char *title, u8 *data, int len)
+{
+	int i;
+
+	printk(KERN_DEBUG "%s: length = %d\n", title, len);
+	for (i = 0; i < len; i++) {
+		printk(KERN_DEBUG "%02x ", data[i]);
+		if ((i & 0xf) == 0xf)
+			printk(KERN_DEBUG "\n");
+	}
+	printk(KERN_DEBUG "\n");
+}
+#endif
+
+static struct usb_tx *alloc_tx_struct(struct tx_cxt *tx)
+{
+	struct usb_tx *t = NULL;
+
+	t = kmalloc(sizeof(*t), GFP_ATOMIC);
+	if (t == NULL)
+		goto out;
+
+	memset(t, 0, sizeof(*t));
+
+	t->urb = usb_alloc_urb(0, GFP_ATOMIC);
+	t->buf = kmalloc(TX_BUF_SIZE, GFP_ATOMIC);
+	if (t->urb == NULL || t->buf == NULL)
+		goto out;
+
+	t->tx_cxt = tx;
+
+	return t;
+out:
+	if (t) {
+		usb_free_urb(t->urb);
+		kfree(t->buf);
+		kfree(t);
+	}
+	return NULL;
+}
+
+static void free_tx_struct(struct usb_tx *t)
+{
+	if (t) {
+		usb_free_urb(t->urb);
+		kfree(t->buf);
+		kfree(t);
+	}
+}
+
+static struct usb_rx *alloc_rx_struct(struct rx_cxt *rx)
+{
+	struct usb_rx *r = NULL;
+
+	r = kmalloc(sizeof(*r), GFP_ATOMIC);
+	if (r == NULL)
+		goto out;
+
+	memset(r, 0, sizeof(*r));
+
+	r->urb = usb_alloc_urb(0, GFP_ATOMIC);
+	r->buf = kmalloc(RX_BUF_SIZE, GFP_ATOMIC);
+	if (r->urb == NULL || r->buf == NULL)
+		goto out;
+
+	r->rx_cxt = rx;
+	return r;
+out:
+	if (r) {
+		usb_free_urb(r->urb);
+		kfree(r->buf);
+		kfree(r);
+	}
+	return NULL;
+}
+
+static void free_rx_struct(struct usb_rx *r)
+{
+	if (r) {
+		usb_free_urb(r->urb);
+		kfree(r->buf);
+		kfree(r);
+	}
+}
+
+/* Before this function is called, spin lock should be locked. */
+static struct usb_tx *get_tx_struct(struct tx_cxt *tx, int *no_spc)
+{
+	struct usb_tx *t;
+
+	if (list_empty(&tx->free_list)) {
+		*no_spc = 1;
+		return NULL;
+	}
+
+	t = list_entry(tx->free_list.next, struct usb_tx, list);
+	list_del(&t->list);
+
+	*no_spc = list_empty(&tx->free_list) ? 1 : 0;
+
+	return t;
+}
+
+/* Before this function is called, spin lock should be locked. */
+static void put_tx_struct(struct tx_cxt *tx, struct usb_tx *t)
+{
+	list_add_tail(&t->list, &tx->free_list);
+}
+
+/* Before this function is called, spin lock should be locked. */
+static struct usb_rx *get_rx_struct(struct rx_cxt *rx)
+{
+	struct usb_rx *r;
+
+	if (list_empty(&rx->free_list)) {
+		r = alloc_rx_struct(rx);
+		if (r == NULL)
+			return NULL;
+
+		list_add(&r->list, &rx->free_list);
+	}
+
+	r = list_entry(rx->free_list.next, struct usb_rx, list);
+	list_del(&r->list);
+	list_add_tail(&r->list, &rx->used_list);
+
+	return r;
+}
+
+/* Before this function is called, spin lock should be locked. */
+static void put_rx_struct(struct rx_cxt *rx, struct usb_rx *r)
+{
+	list_del(&r->list);
+	list_add(&r->list, &rx->free_list);
+}
+
+static int init_usb(struct usbwm_dev *udev)
+{
+	int ret = 0, i;
+	struct tx_cxt	*tx = &udev->tx;
+	struct rx_cxt	*rx = &udev->rx;
+	struct usb_tx	*t;
+	struct usb_rx	*r;
+
+	INIT_LIST_HEAD(&tx->free_list);
+	INIT_LIST_HEAD(&tx->sdu_list);
+	INIT_LIST_HEAD(&tx->hci_list);
+#if defined(CONFIG_WIMAX_GDM72XX_USB_PM) || defined(CONFIG_WIMAX_GDM72XX_K_MODE)
+	INIT_LIST_HEAD(&tx->pending_list);
+#endif
+
+	INIT_LIST_HEAD(&rx->free_list);
+	INIT_LIST_HEAD(&rx->used_list);
+
+	spin_lock_init(&tx->lock);
+	spin_lock_init(&rx->lock);
+
+	for (i = 0; i < MAX_NR_SDU_BUF; i++) {
+		t = alloc_tx_struct(tx);
+		if (t == NULL) {
+			ret = -ENOMEM;
+			goto fail;
+		}
+		list_add(&t->list, &tx->free_list);
+	}
+
+	r = alloc_rx_struct(rx);
+	if (r == NULL) {
+		ret = -ENOMEM;
+		goto fail;
+	}
+
+	list_add(&r->list, &rx->free_list);
+	return ret;
+
+fail:
+	release_usb(udev);
+	return ret;
+}
+
+static void release_usb(struct usbwm_dev *udev)
+{
+	struct tx_cxt	*tx = &udev->tx;
+	struct rx_cxt	*rx = &udev->rx;
+	struct usb_tx	*t, *t_next;
+	struct usb_rx	*r, *r_next;
+
+	list_for_each_entry_safe(t, t_next, &tx->sdu_list, list) {
+		list_del(&t->list);
+		free_tx_struct(t);
+	}
+
+	list_for_each_entry_safe(t, t_next, &tx->hci_list, list) {
+		list_del(&t->list);
+		free_tx_struct(t);
+	}
+
+	list_for_each_entry_safe(t, t_next, &tx->free_list, list) {
+		list_del(&t->list);
+		free_tx_struct(t);
+	}
+
+	list_for_each_entry_safe(r, r_next, &rx->free_list, list) {
+		list_del(&r->list);
+		free_rx_struct(r);
+	}
+
+	list_for_each_entry_safe(r, r_next, &rx->used_list, list) {
+		list_del(&r->list);
+		free_rx_struct(r);
+	}
+}
+
+static void gdm_usb_send_complete(struct urb *urb)
+{
+	struct usb_tx *t = urb->context;
+	struct tx_cxt *tx = t->tx_cxt;
+	u8 *pkt = t->buf;
+	u16 cmd_evt;
+	unsigned long flags;
+
+	/* Completion by usb_unlink_urb */
+	if (urb->status == -ECONNRESET)
+		return;
+
+	spin_lock_irqsave(&tx->lock, flags);
+
+	if (t->callback)
+		t->callback(t->cb_data);
+
+	/* Delete from sdu list or hci list. */
+	list_del(&t->list);
+
+	cmd_evt = (pkt[0] << 8) | pkt[1];
+	if (cmd_evt == WIMAX_TX_SDU)
+		put_tx_struct(tx, t);
+	else
+		free_tx_struct(t);
+
+	spin_unlock_irqrestore(&tx->lock, flags);
+}
+
+static int gdm_usb_send(void *priv_dev, void *data, int len,
+			void (*cb)(void *data), void *cb_data)
+{
+	struct usbwm_dev *udev = priv_dev;
+	struct usb_device *usbdev = udev->usbdev;
+	struct tx_cxt *tx = &udev->tx;
+	struct usb_tx *t;
+	int padding = udev->padding;
+	int no_spc = 0, ret;
+	u8 *pkt = data;
+	u16 cmd_evt;
+	unsigned long flags;
+
+	if (!udev->usbdev) {
+		printk(KERN_ERR "%s: No such device\n", __func__);
+		return -ENODEV;
+	}
+
+	BUG_ON(len > TX_BUF_SIZE - padding - 1);
+
+	spin_lock_irqsave(&tx->lock, flags);
+
+	cmd_evt = (pkt[0] << 8) | pkt[1];
+	if (cmd_evt == WIMAX_TX_SDU) {
+		t = get_tx_struct(tx, &no_spc);
+		if (t == NULL) {
+			/* This case must not happen. */
+			spin_unlock_irqrestore(&tx->lock, flags);
+			return -ENOSPC;
+		}
+		list_add_tail(&t->list, &tx->sdu_list);
+	} else {
+		t = alloc_tx_struct(tx);
+		if (t == NULL) {
+			spin_unlock_irqrestore(&tx->lock, flags);
+			return -ENOMEM;
+		}
+		list_add_tail(&t->list, &tx->hci_list);
+	}
+
+	memcpy(t->buf + padding, data, len);
+	t->callback = cb;
+	t->cb_data = cb_data;
+
+	/*
+	 * In some cases, USB Module of WiMax is blocked when data size is
+	 * the multiple of 512. So, increment length by one in that case.
+	 */
+	if ((len % 512) == 0)
+		len++;
+
+	usb_fill_bulk_urb(t->urb,
+			usbdev,
+			usb_sndbulkpipe(usbdev, 1),
+			t->buf,
+			len + padding,
+			gdm_usb_send_complete,
+			t);
+
+#ifdef DEBUG
+	hexdump("usb_send", t->buf, len + padding);
+#endif
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+	if (usbdev->state & USB_STATE_SUSPENDED) {
+		list_add_tail(&t->p_list, &tx->pending_list);
+		schedule_work(&udev->pm_ws);
+		goto out;
+	}
+#endif /* CONFIG_WIMAX_GDM72XX_USB_PM */
+
+#ifdef CONFIG_WIMAX_GDM72XX_K_MODE
+	if (udev->bw_switch) {
+		list_add_tail(&t->p_list, &tx->pending_list);
+		goto out;
+	} else if (cmd_evt == WIMAX_SCAN) {
+		struct rx_cxt *rx;
+		struct usb_rx *r;
+
+		rx = &udev->rx;
+
+		list_for_each_entry(r, &rx->used_list, list)
+			usb_unlink_urb(r->urb);
+		udev->bw_switch = 1;
+
+		spin_lock(&k_lock);
+		list_add_tail(&udev->list, &k_list);
+		spin_unlock(&k_lock);
+
+		wake_up(&k_wait);
+	}
+#endif /* CONFIG_WIMAX_GDM72XX_K_MODE */
+
+	ret = usb_submit_urb(t->urb, GFP_ATOMIC);
+	if (ret)
+		goto send_fail;
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+	usb_mark_last_busy(usbdev);
+#endif /* CONFIG_WIMAX_GDM72XX_USB_PM */
+
+#if defined(CONFIG_WIMAX_GDM72XX_USB_PM) || defined(CONFIG_WIMAX_GDM72XX_K_MODE)
+out:
+#endif
+	spin_unlock_irqrestore(&tx->lock, flags);
+
+	if (no_spc)
+		return -ENOSPC;
+
+	return 0;
+
+send_fail:
+	t->callback = NULL;
+	gdm_usb_send_complete(t->urb);
+	spin_unlock_irqrestore(&tx->lock, flags);
+	return ret;
+}
+
+static void gdm_usb_rcv_complete(struct urb *urb)
+{
+	struct usb_rx *r = urb->context;
+	struct rx_cxt *rx = r->rx_cxt;
+	struct usbwm_dev *udev = container_of(r->rx_cxt, struct usbwm_dev, rx);
+	struct tx_cxt *tx = &udev->tx;
+	struct usb_tx *t;
+	u16 cmd_evt;
+	unsigned long flags;
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+	struct usb_device *dev = urb->dev;
+#endif
+
+	/* Completion by usb_unlink_urb */
+	if (urb->status == -ECONNRESET)
+		return;
+
+	spin_lock_irqsave(&tx->lock, flags);
+
+	if (!urb->status) {
+		cmd_evt = (r->buf[0] << 8) | (r->buf[1]);
+#ifdef DEBUG
+		hexdump("usb_receive", r->buf, urb->actual_length);
+#endif
+		if (cmd_evt == WIMAX_SDU_TX_FLOW) {
+			if (r->buf[4] == 0) {
+#ifdef DEBUG
+				printk(KERN_DEBUG "WIMAX ==> STOP SDU TX\n");
+#endif
+				list_for_each_entry(t, &tx->sdu_list, list)
+					usb_unlink_urb(t->urb);
+			} else if (r->buf[4] == 1) {
+#ifdef DEBUG
+				printk(KERN_DEBUG "WIMAX ==> START SDU TX\n");
+#endif
+				list_for_each_entry(t, &tx->sdu_list, list) {
+					usb_submit_urb(t->urb, GFP_ATOMIC);
+				}
+				/*
+				 * If free buffer for sdu tx doesn't
+				 * exist, then tx queue should not be
+				 * woken. For this reason, don't pass
+				 * the command, START_SDU_TX.
+				 */
+				if (list_empty(&tx->free_list))
+					urb->actual_length = 0;
+			}
+		}
+	}
+
+	if (!urb->status && r->callback)
+		r->callback(r->cb_data, r->buf, urb->actual_length);
+
+	spin_lock(&rx->lock);
+	put_rx_struct(rx, r);
+	spin_unlock(&rx->lock);
+
+	spin_unlock_irqrestore(&tx->lock, flags);
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+	usb_mark_last_busy(dev);
+#endif
+}
+
+static int gdm_usb_receive(void *priv_dev,
+			void (*cb)(void *cb_data, void *data, int len),
+			void *cb_data)
+{
+	struct usbwm_dev *udev = priv_dev;
+	struct usb_device *usbdev = udev->usbdev;
+	struct rx_cxt *rx = &udev->rx;
+	struct usb_rx *r;
+	unsigned long flags;
+
+	if (!udev->usbdev) {
+		printk(KERN_ERR "%s: No such device\n", __func__);
+		return -ENODEV;
+	}
+
+	spin_lock_irqsave(&rx->lock, flags);
+	r = get_rx_struct(rx);
+	spin_unlock_irqrestore(&rx->lock, flags);
+
+	if (r == NULL)
+		return -ENOMEM;
+
+	r->callback = cb;
+	r->cb_data = cb_data;
+
+	usb_fill_bulk_urb(r->urb,
+			usbdev,
+			usb_rcvbulkpipe(usbdev, 0x82),
+			r->buf,
+			RX_BUF_SIZE,
+			gdm_usb_rcv_complete,
+			r);
+
+	return usb_submit_urb(r->urb, GFP_ATOMIC);
+}
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+static void do_pm_control(struct work_struct *work)
+{
+	struct usbwm_dev *udev = container_of(work, struct usbwm_dev, pm_ws);
+	struct tx_cxt *tx = &udev->tx;
+	int ret;
+	unsigned long flags;
+
+	ret = usb_autopm_get_interface(udev->intf);
+	if (!ret)
+		usb_autopm_put_interface(udev->intf);
+
+	spin_lock_irqsave(&tx->lock, flags);
+	if (!(udev->usbdev->state & USB_STATE_SUSPENDED)
+		&& (!list_empty(&tx->hci_list) || !list_empty(&tx->sdu_list))) {
+		struct usb_tx *t, *temp;
+
+		list_for_each_entry_safe(t, temp, &tx->pending_list, p_list) {
+			list_del(&t->p_list);
+			ret =  usb_submit_urb(t->urb, GFP_ATOMIC);
+
+			if (ret) {
+				t->callback = NULL;
+				gdm_usb_send_complete(t->urb);
+			}
+		}
+	}
+	spin_unlock_irqrestore(&tx->lock, flags);
+}
+#endif /* CONFIG_WIMAX_GDM72XX_USB_PM */
+
+static int gdm_usb_probe(struct usb_interface *intf,
+				const struct usb_device_id *id)
+{
+	int ret = 0;
+	u8 bConfigurationValue;
+	struct phy_dev *phy_dev = NULL;
+	struct usbwm_dev *udev = NULL;
+	u16 idVendor, idProduct, bcdDevice;
+
+	struct usb_device *usbdev = interface_to_usbdev(intf);
+
+	usb_get_dev(usbdev);
+	bConfigurationValue = usbdev->actconfig->desc.bConfigurationValue;
+
+	/*USB description is set up with Little-Endian*/
+	idVendor = L2H(usbdev->descriptor.idVendor);
+	idProduct = L2H(usbdev->descriptor.idProduct);
+	bcdDevice = L2H(usbdev->descriptor.bcdDevice);
+
+	printk(KERN_INFO "Found GDM USB VID = 0x%04x PID = 0x%04x...\n",
+		idVendor, idProduct);
+	printk(KERN_INFO "GCT WiMax driver version %s\n", DRIVER_VERSION);
+
+
+	if (idProduct == EMERGENCY_PID) {
+		ret = usb_emergency(usbdev);
+		goto out;
+	}
+
+	/* Support for EEPROM bootloader */
+	if (bConfigurationValue == DOWNLOAD_CONF_VALUE ||
+		idProduct & B_DOWNLOAD) {
+		ret = usb_boot(usbdev, bcdDevice);
+		goto out;
+	}
+
+	phy_dev = kmalloc(sizeof(*phy_dev), GFP_KERNEL);
+	if (phy_dev == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+	udev = kmalloc(sizeof(*udev), GFP_KERNEL);
+	if (udev == NULL) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	memset(phy_dev, 0, sizeof(*phy_dev));
+	memset(udev, 0, sizeof(*udev));
+
+	if (idProduct == 0x7205 || idProduct == 0x7206)
+		udev->padding = GDM7205_PADDING;
+	else
+		udev->padding = 0;
+
+	phy_dev->priv_dev = (void *)udev;
+	phy_dev->send_func = gdm_usb_send;
+	phy_dev->rcv_func = gdm_usb_receive;
+
+	ret = init_usb(udev);
+	if (ret < 0)
+		goto out;
+
+	udev->usbdev = usbdev;
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+	udev->intf = intf;
+
+	intf->needs_remote_wakeup = 1;
+	device_init_wakeup(&intf->dev, 1);
+
+	pm_runtime_set_autosuspend_delay(&usbdev->dev, 10 * 1000); /* msec */
+
+	INIT_WORK(&udev->pm_ws, do_pm_control);
+#endif /* CONFIG_WIMAX_GDM72XX_USB_PM */
+
+	ret = register_wimax_device(phy_dev);
+
+out:
+	if (ret) {
+		kfree(phy_dev);
+		kfree(udev);
+	}
+	usb_set_intfdata(intf, phy_dev);
+	return ret;
+}
+
+static void gdm_usb_disconnect(struct usb_interface *intf)
+{
+	u8 bConfigurationValue;
+	struct phy_dev *phy_dev;
+	struct usbwm_dev *udev;
+	u16 idProduct;
+	struct usb_device *usbdev = interface_to_usbdev(intf);
+
+	bConfigurationValue = usbdev->actconfig->desc.bConfigurationValue;
+	phy_dev = usb_get_intfdata(intf);
+
+	/*USB description is set up with Little-Endian*/
+	idProduct = L2H(usbdev->descriptor.idProduct);
+
+	if (idProduct != EMERGENCY_PID &&
+			bConfigurationValue != DOWNLOAD_CONF_VALUE &&
+			(idProduct & B_DOWNLOAD) == 0) {
+		udev = phy_dev->priv_dev;
+		udev->usbdev = NULL;
+
+		unregister_wimax_device(phy_dev);
+		release_usb(udev);
+		kfree(udev);
+		kfree(phy_dev);
+	}
+
+	usb_put_dev(usbdev);
+}
+
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+static int gdm_suspend(struct usb_interface *intf, pm_message_t pm_msg)
+{
+	struct phy_dev *phy_dev;
+	struct usbwm_dev *udev;
+	struct rx_cxt *rx;
+	struct usb_rx *r;
+
+	phy_dev = usb_get_intfdata(intf);
+	udev = phy_dev->priv_dev;
+	rx = &udev->rx;
+
+	list_for_each_entry(r, &rx->used_list, list)
+		usb_unlink_urb(r->urb);
+
+	return 0;
+}
+
+static int gdm_resume(struct usb_interface *intf)
+{
+	struct phy_dev *phy_dev;
+	struct usbwm_dev *udev;
+	struct rx_cxt *rx;
+	struct usb_rx *r;
+
+	phy_dev = usb_get_intfdata(intf);
+	udev = phy_dev->priv_dev;
+	rx = &udev->rx;
+
+	list_for_each_entry(r, &rx->used_list, list)
+		usb_submit_urb(r->urb, GFP_ATOMIC);
+
+	return 0;
+}
+
+#endif /* CONFIG_WIMAX_GDM72XX_USB_PM */
+
+#ifdef CONFIG_WIMAX_GDM72XX_K_MODE
+static int k_mode_thread(void *arg)
+{
+	struct usbwm_dev *udev;
+	struct tx_cxt *tx;
+	struct rx_cxt *rx;
+	struct usb_tx *t, *temp;
+	struct usb_rx *r;
+	unsigned long flags, flags2, expire;
+	int ret;
+
+	daemonize("k_mode_wimax");
+
+	while (!k_mode_stop) {
+
+		spin_lock_irqsave(&k_lock, flags2);
+		while (!list_empty(&k_list)) {
+
+			udev = list_entry(k_list.next, struct usbwm_dev, list);
+			tx = &udev->tx;
+			rx = &udev->rx;
+
+			list_del(&udev->list);
+			spin_unlock_irqrestore(&k_lock, flags2);
+
+			expire = jiffies + K_WAIT_TIME;
+			while (jiffies < expire)
+				schedule_timeout(K_WAIT_TIME);
+
+			list_for_each_entry(r, &rx->used_list, list)
+				usb_submit_urb(r->urb, GFP_ATOMIC);
+
+			spin_lock_irqsave(&tx->lock, flags);
+
+			list_for_each_entry_safe(t, temp, &tx->pending_list,
+						p_list) {
+				list_del(&t->p_list);
+				ret = usb_submit_urb(t->urb, GFP_ATOMIC);
+
+				if (ret) {
+					t->callback = NULL;
+					gdm_usb_send_complete(t->urb);
+				}
+			}
+
+			udev->bw_switch = 0;
+			spin_unlock_irqrestore(&tx->lock, flags);
+
+			spin_lock_irqsave(&k_lock, flags2);
+		}
+		spin_unlock_irqrestore(&k_lock, flags2);
+
+		interruptible_sleep_on(&k_wait);
+	}
+	return 0;
+}
+#endif /* CONFIG_WIMAX_GDM72XX_K_MODE */
+
+static struct usb_driver gdm_usb_driver = {
+	.name = "gdm_wimax",
+	.probe = gdm_usb_probe,
+	.disconnect = gdm_usb_disconnect,
+	.id_table = id_table,
+#ifdef CONFIG_WIMAX_GDM72XX_USB_PM
+	.supports_autosuspend = 1,
+	.suspend = gdm_suspend,
+	.resume = gdm_resume,
+	.reset_resume = gdm_resume,
+#endif
+};
+
+static int __init usb_gdm_wimax_init(void)
+{
+#ifdef CONFIG_WIMAX_GDM72XX_K_MODE
+	kernel_thread(k_mode_thread, NULL, CLONE_KERNEL);
+#endif /* CONFIG_WIMAX_GDM72XX_K_MODE */
+	return usb_register(&gdm_usb_driver);
+}
+
+static void __exit usb_gdm_wimax_exit(void)
+{
+#ifdef CONFIG_WIMAX_GDM72XX_K_MODE
+	k_mode_stop = 1;
+	wake_up(&k_wait);
+#endif
+	usb_deregister(&gdm_usb_driver);
+}
+
+module_init(usb_gdm_wimax_init);
+module_exit(usb_gdm_wimax_exit);
+
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_DESCRIPTION("GCT WiMax Device Driver");
+MODULE_AUTHOR("Ethan Park");
+MODULE_LICENSE("GPL");