usb: misc: Add kickstart bridge driver
kickstart bridge driver will be used to download boot images
to mdm, ram-dumps and efs sync.
Change-Id: Id35e2da664ebf4a16c84d6fb67fbf38a2855356a
Signed-off-by: Vamsi Krishna <vskrishn@codeaurora.org>
diff --git a/drivers/usb/misc/ks_bridge.c b/drivers/usb/misc/ks_bridge.c
new file mode 100644
index 0000000..10cbe59
--- /dev/null
+++ b/drivers/usb/misc/ks_bridge.c
@@ -0,0 +1,805 @@
+/*
+ * Copyright (c) 2012, Code Aurora Forum. 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.
+ */
+
+/* add additional information to our printk's */
+#define pr_fmt(fmt) "%s: " fmt "\n", __func__
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/kref.h>
+#include <linux/platform_device.h>
+#include <linux/ratelimit.h>
+#include <linux/uaccess.h>
+#include <linux/usb.h>
+#include <linux/debugfs.h>
+#include <linux/seq_file.h>
+#include <linux/miscdevice.h>
+#include <linux/list.h>
+#include <linux/wait.h>
+
+#define DRIVER_DESC "USB host ks bridge driver"
+#define DRIVER_VERSION "1.0"
+
+struct data_pkt {
+ int n_read;
+ char *buf;
+ size_t len;
+ struct list_head list;
+ void *ctxt;
+};
+
+#define FILE_OPENED BIT(0)
+#define USB_DEV_CONNECTED BIT(1)
+#define NO_RX_REQS 10
+#define NO_BRIDGE_INSTANCES 2
+#define BOOT_BRIDGE_INDEX 0
+#define EFS_BRIDGE_INDEX 1
+#define MAX_DATA_PKT_SIZE 16384
+
+struct ks_bridge {
+ char *name;
+ spinlock_t lock;
+ struct workqueue_struct *wq;
+ struct work_struct to_mdm_work;
+ struct work_struct start_rx_work;
+ struct list_head to_mdm_list;
+ struct list_head to_ks_list;
+ wait_queue_head_t ks_wait_q;
+
+ /* usb specific */
+ struct usb_device *udev;
+ struct usb_interface *ifc;
+ __u8 in_epAddr;
+ __u8 out_epAddr;
+ unsigned int in_pipe;
+ unsigned int out_pipe;
+ struct usb_anchor submitted;
+
+ unsigned long flags;
+ unsigned int alloced_read_pkts;
+
+#define DBG_MSG_LEN 40
+#define DBG_MAX_MSG 500
+ unsigned int dbg_idx;
+ rwlock_t dbg_lock;
+ char (dbgbuf[DBG_MAX_MSG])[DBG_MSG_LEN]; /* buffer */
+};
+struct ks_bridge *__ksb[NO_BRIDGE_INSTANCES];
+
+/* by default debugging is enabled */
+static unsigned int enable_dbg = 1;
+module_param(enable_dbg, uint, S_IRUGO | S_IWUSR);
+
+static void
+dbg_log_event(struct ks_bridge *ksb, char *event, int d1, int d2)
+{
+ unsigned long flags;
+ unsigned long long t;
+ unsigned long nanosec;
+
+ if (!enable_dbg)
+ return;
+
+ write_lock_irqsave(&ksb->dbg_lock, flags);
+ t = cpu_clock(smp_processor_id());
+ nanosec = do_div(t, 1000000000)/1000;
+ scnprintf(ksb->dbgbuf[ksb->dbg_idx], DBG_MSG_LEN, "%5lu.%06lu:%s:%x:%x",
+ (unsigned long)t, nanosec, event, d1, d2);
+
+ ksb->dbg_idx++;
+ ksb->dbg_idx = ksb->dbg_idx % DBG_MAX_MSG;
+ write_unlock_irqrestore(&ksb->dbg_lock, flags);
+}
+
+static
+struct data_pkt *ksb_alloc_data_pkt(size_t count, gfp_t flags, void *ctxt)
+{
+ struct data_pkt *pkt;
+
+ pkt = kzalloc(sizeof(struct data_pkt), flags);
+ if (!pkt) {
+ pr_err("failed to allocate data packet\n");
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pkt->buf = kmalloc(count, flags);
+ if (!pkt->buf) {
+ pr_err("failed to allocate data buffer\n");
+ kfree(pkt);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ pkt->len = count;
+ INIT_LIST_HEAD(&pkt->list);
+ pkt->ctxt = ctxt;
+
+ return pkt;
+}
+
+static void ksb_free_data_pkt(struct data_pkt *pkt)
+{
+ kfree(pkt->buf);
+ kfree(pkt);
+}
+
+
+static ssize_t ksb_fs_read(struct file *fp, char __user *buf,
+ size_t count, loff_t *pos)
+{
+ int ret;
+ unsigned long flags;
+ struct ks_bridge *ksb = fp->private_data;
+ struct data_pkt *pkt;
+ size_t space, copied;
+
+read_start:
+ if (!test_bit(USB_DEV_CONNECTED, &ksb->flags))
+ return -ENODEV;
+
+ spin_lock_irqsave(&ksb->lock, flags);
+ if (list_empty(&ksb->to_ks_list)) {
+ spin_unlock_irqrestore(&ksb->lock, flags);
+ ret = wait_event_interruptible(ksb->ks_wait_q,
+ !list_empty(&ksb->to_ks_list) ||
+ !test_bit(USB_DEV_CONNECTED, &ksb->flags));
+ if (ret < 0)
+ return ret;
+
+ goto read_start;
+ }
+
+ space = count;
+ copied = 0;
+ while (!list_empty(&ksb->to_ks_list) && space) {
+ size_t len;
+
+ pkt = list_first_entry(&ksb->to_ks_list, struct data_pkt, list);
+ len = min_t(size_t, space, pkt->len);
+ pkt->n_read += len;
+ spin_unlock_irqrestore(&ksb->lock, flags);
+
+ ret = copy_to_user(buf + copied, pkt->buf, len);
+ if (ret) {
+ pr_err("copy_to_user failed err:%d\n", ret);
+ ksb_free_data_pkt(pkt);
+ ksb->alloced_read_pkts--;
+ return ret;
+ }
+
+ space -= len;
+ copied += len;
+
+ spin_lock_irqsave(&ksb->lock, flags);
+ if (pkt->n_read == pkt->len) {
+ list_del_init(&pkt->list);
+ ksb_free_data_pkt(pkt);
+ ksb->alloced_read_pkts--;
+ }
+ }
+ spin_unlock_irqrestore(&ksb->lock, flags);
+
+ dbg_log_event(ksb, "KS_READ", copied, 0);
+
+ pr_debug("count:%d space:%d copied:%d", count, space, copied);
+
+ return copied;
+}
+
+static void ksb_tx_cb(struct urb *urb)
+{
+ struct data_pkt *pkt = urb->context;
+ struct ks_bridge *ksb = pkt->ctxt;
+
+ dbg_log_event(ksb, "C TX_URB", urb->status, 0);
+ pr_debug("status:%d", urb->status);
+
+ if (ksb->ifc)
+ usb_autopm_put_interface_async(ksb->ifc);
+
+ if (urb->status < 0)
+ pr_err_ratelimited("urb failed with err:%d", urb->status);
+
+ ksb_free_data_pkt(pkt);
+}
+
+static void ksb_tomdm_work(struct work_struct *w)
+{
+ struct ks_bridge *ksb = container_of(w, struct ks_bridge, to_mdm_work);
+ struct data_pkt *pkt;
+ unsigned long flags;
+ struct urb *urb;
+ int ret;
+
+ spin_lock_irqsave(&ksb->lock, flags);
+ while (!list_empty(&ksb->to_mdm_list)
+ && test_bit(USB_DEV_CONNECTED, &ksb->flags)) {
+ pkt = list_first_entry(&ksb->to_mdm_list,
+ struct data_pkt, list);
+ list_del_init(&pkt->list);
+ spin_unlock_irqrestore(&ksb->lock, flags);
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ pr_err_ratelimited("unable to allocate urb");
+ ksb_free_data_pkt(pkt);
+ return;
+ }
+
+ ret = usb_autopm_get_interface(ksb->ifc);
+ if (ret < 0 && ret != -EAGAIN && ret != -EACCES) {
+ pr_err_ratelimited("autopm_get failed:%d", ret);
+ usb_free_urb(urb);
+ ksb_free_data_pkt(pkt);
+ return;
+ }
+ usb_fill_bulk_urb(urb, ksb->udev, ksb->out_pipe,
+ pkt->buf, pkt->len, ksb_tx_cb, pkt);
+ usb_anchor_urb(urb, &ksb->submitted);
+
+ dbg_log_event(ksb, "S TX_URB", pkt->len, 0);
+
+ ret = usb_submit_urb(urb, GFP_KERNEL);
+ if (ret) {
+ pr_err("out urb submission failed");
+ usb_unanchor_urb(urb);
+ usb_free_urb(urb);
+ ksb_free_data_pkt(pkt);
+ usb_autopm_put_interface(ksb->ifc);
+ return;
+ }
+
+ spin_lock_irqsave(&ksb->lock, flags);
+ }
+ spin_unlock_irqrestore(&ksb->lock, flags);
+}
+
+static ssize_t ksb_fs_write(struct file *fp, const char __user *buf,
+ size_t count, loff_t *pos)
+{
+ int ret;
+ struct data_pkt *pkt;
+ unsigned long flags;
+ struct ks_bridge *ksb = fp->private_data;
+
+ pkt = ksb_alloc_data_pkt(count, GFP_KERNEL, ksb);
+ if (IS_ERR(pkt)) {
+ pr_err("unable to allocate data packet");
+ return PTR_ERR(pkt);
+ }
+
+ ret = copy_from_user(pkt->buf, buf, count);
+ if (ret) {
+ pr_err("copy_from_user failed: err:%d", ret);
+ ksb_free_data_pkt(pkt);
+ return ret;
+ }
+
+ spin_lock_irqsave(&ksb->lock, flags);
+ list_add_tail(&pkt->list, &ksb->to_mdm_list);
+ spin_unlock_irqrestore(&ksb->lock, flags);
+
+ queue_work(ksb->wq, &ksb->to_mdm_work);
+
+ return count;
+}
+
+static int efs_fs_open(struct inode *ip, struct file *fp)
+{
+ struct ks_bridge *ksb = __ksb[EFS_BRIDGE_INDEX];
+
+ pr_debug(":%s", ksb->name);
+ dbg_log_event(ksb, "EFS-FS-OPEN", 0, 0);
+
+ if (!ksb) {
+ pr_err("ksb is being removed");
+ return -ENODEV;
+ }
+
+ fp->private_data = ksb;
+ set_bit(FILE_OPENED, &ksb->flags);
+
+ if (test_bit(USB_DEV_CONNECTED, &ksb->flags))
+ queue_work(ksb->wq, &ksb->start_rx_work);
+
+ return 0;
+}
+
+static int ksb_fs_open(struct inode *ip, struct file *fp)
+{
+ struct ks_bridge *ksb = __ksb[BOOT_BRIDGE_INDEX];
+
+ pr_debug(":%s", ksb->name);
+ dbg_log_event(ksb, "KS-FS-OPEN", 0, 0);
+
+ if (!ksb) {
+ pr_err("ksb is being removed");
+ return -ENODEV;
+ }
+
+ fp->private_data = ksb;
+ set_bit(FILE_OPENED, &ksb->flags);
+
+ if (test_bit(USB_DEV_CONNECTED, &ksb->flags))
+ queue_work(ksb->wq, &ksb->start_rx_work);
+
+ return 0;
+}
+
+static int ksb_fs_release(struct inode *ip, struct file *fp)
+{
+ struct ks_bridge *ksb = fp->private_data;
+
+ pr_debug(":%s", ksb->name);
+ dbg_log_event(ksb, "FS-RELEASE", 0, 0);
+
+ clear_bit(FILE_OPENED, &ksb->flags);
+ fp->private_data = NULL;
+
+ return 0;
+}
+
+static const struct file_operations ksb_fops = {
+ .owner = THIS_MODULE,
+ .read = ksb_fs_read,
+ .write = ksb_fs_write,
+ .open = ksb_fs_open,
+ .release = ksb_fs_release,
+};
+
+static struct miscdevice ksb_fboot_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "ks_bridge",
+ .fops = &ksb_fops,
+};
+
+static const struct file_operations efs_fops = {
+ .owner = THIS_MODULE,
+ .read = ksb_fs_read,
+ .write = ksb_fs_write,
+ .open = efs_fs_open,
+ .release = ksb_fs_release,
+};
+
+static struct miscdevice ksb_efs_dev = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "efs_bridge",
+ .fops = &efs_fops,
+};
+
+static const struct usb_device_id ksb_usb_ids[] = {
+ { USB_DEVICE(0x5c6, 0x9008),
+ .driver_info = (unsigned long)&ksb_fboot_dev, },
+ { USB_DEVICE(0x5c6, 0x9048),
+ .driver_info = (unsigned long)&ksb_efs_dev, },
+ { USB_DEVICE(0x5c6, 0x904C),
+ .driver_info = (unsigned long)&ksb_efs_dev, },
+
+ {} /* terminating entry */
+};
+MODULE_DEVICE_TABLE(usb, ksb_usb_ids);
+
+static void ksb_rx_cb(struct urb *urb);
+static void submit_one_urb(struct ks_bridge *ksb)
+{
+ struct data_pkt *pkt;
+ struct urb *urb;
+ int ret;
+
+ pkt = ksb_alloc_data_pkt(MAX_DATA_PKT_SIZE, GFP_ATOMIC, ksb);
+ if (IS_ERR(pkt)) {
+ pr_err("unable to allocate data pkt");
+ return;
+ }
+
+ urb = usb_alloc_urb(0, GFP_ATOMIC);
+ if (!urb) {
+ pr_err("unable to allocate urb");
+ ksb_free_data_pkt(pkt);
+ return;
+ }
+ ksb->alloced_read_pkts++;
+
+ usb_fill_bulk_urb(urb, ksb->udev, ksb->in_pipe,
+ pkt->buf, pkt->len,
+ ksb_rx_cb, pkt);
+ usb_anchor_urb(urb, &ksb->submitted);
+
+ dbg_log_event(ksb, "S RX_URB", pkt->len, 0);
+
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret) {
+ pr_err("in urb submission failed");
+ usb_unanchor_urb(urb);
+ usb_free_urb(urb);
+ ksb_free_data_pkt(pkt);
+ ksb->alloced_read_pkts--;
+ return;
+ }
+
+ usb_free_urb(urb);
+}
+static void ksb_rx_cb(struct urb *urb)
+{
+ struct data_pkt *pkt = urb->context;
+ struct ks_bridge *ksb = pkt->ctxt;
+
+ dbg_log_event(ksb, "C RX_URB", urb->status, urb->actual_length);
+
+ pr_debug("status:%d actual:%d", urb->status, urb->actual_length);
+
+ if (urb->status < 0) {
+ if (urb->status != -ESHUTDOWN && urb->status != -ENOENT)
+ pr_err_ratelimited("urb failed with err:%d",
+ urb->status);
+ ksb_free_data_pkt(pkt);
+ ksb->alloced_read_pkts--;
+ return;
+ }
+
+ if (urb->actual_length == 0) {
+ ksb_free_data_pkt(pkt);
+ ksb->alloced_read_pkts--;
+ goto resubmit_urb;
+ }
+
+ spin_lock(&ksb->lock);
+ pkt->len = urb->actual_length;
+ list_add_tail(&pkt->list, &ksb->to_ks_list);
+ spin_unlock(&ksb->lock);
+
+ /* wake up read thread */
+ wake_up(&ksb->ks_wait_q);
+
+resubmit_urb:
+ submit_one_urb(ksb);
+
+}
+
+static void ksb_start_rx_work(struct work_struct *w)
+{
+ struct ks_bridge *ksb =
+ container_of(w, struct ks_bridge, start_rx_work);
+ struct data_pkt *pkt;
+ struct urb *urb;
+ int i = 0;
+ int ret;
+
+ for (i = 0; i < NO_RX_REQS; i++) {
+ pkt = ksb_alloc_data_pkt(MAX_DATA_PKT_SIZE, GFP_KERNEL, ksb);
+ if (IS_ERR(pkt)) {
+ pr_err("unable to allocate data pkt");
+ return;
+ }
+
+ urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!urb) {
+ pr_err("unable to allocate urb");
+ ksb_free_data_pkt(pkt);
+ return;
+ }
+
+ ret = usb_autopm_get_interface(ksb->ifc);
+ if (ret < 0 && ret != -EAGAIN && ret != -EACCES) {
+ pr_err_ratelimited("autopm_get failed:%d", ret);
+ usb_free_urb(urb);
+ ksb_free_data_pkt(pkt);
+ return;
+ }
+ ksb->alloced_read_pkts++;
+
+ usb_fill_bulk_urb(urb, ksb->udev, ksb->in_pipe,
+ pkt->buf, pkt->len,
+ ksb_rx_cb, pkt);
+ usb_anchor_urb(urb, &ksb->submitted);
+
+ dbg_log_event(ksb, "S RX_URB", pkt->len, 0);
+
+ ret = usb_submit_urb(urb, GFP_KERNEL);
+ if (ret) {
+ pr_err("in urb submission failed");
+ usb_unanchor_urb(urb);
+ usb_free_urb(urb);
+ ksb_free_data_pkt(pkt);
+ ksb->alloced_read_pkts--;
+ usb_autopm_put_interface(ksb->ifc);
+ return;
+ }
+
+ usb_autopm_put_interface_async(ksb->ifc);
+ usb_free_urb(urb);
+ }
+}
+
+static int
+ksb_usb_probe(struct usb_interface *ifc, const struct usb_device_id *id)
+{
+ __u8 ifc_num;
+ struct usb_host_interface *ifc_desc;
+ struct usb_endpoint_descriptor *ep_desc;
+ int i;
+ struct ks_bridge *ksb;
+ struct miscdevice *fs_dev;
+
+ ifc_num = ifc->cur_altsetting->desc.bInterfaceNumber;
+
+ switch (id->idProduct) {
+ case 0x9008:
+ if (ifc_num != 0)
+ return -ENODEV;
+ ksb = __ksb[BOOT_BRIDGE_INDEX];
+ break;
+ case 0x9048:
+ case 0x904C:
+ if (ifc_num != 2)
+ return -ENODEV;
+ ksb = __ksb[EFS_BRIDGE_INDEX];
+ break;
+ default:
+ return -ENODEV;
+ }
+
+ if (!ksb) {
+ pr_err("ksb is not initialized");
+ return -ENODEV;
+ }
+
+ ksb->udev = usb_get_dev(interface_to_usbdev(ifc));
+ ksb->ifc = ifc;
+ ifc_desc = ifc->cur_altsetting;
+
+ for (i = 0; i < ifc_desc->desc.bNumEndpoints; i++) {
+ ep_desc = &ifc_desc->endpoint[i].desc;
+
+ if (!ksb->in_epAddr && usb_endpoint_is_bulk_in(ep_desc))
+ ksb->in_epAddr = ep_desc->bEndpointAddress;
+
+ if (!ksb->out_epAddr && usb_endpoint_is_bulk_out(ep_desc))
+ ksb->out_epAddr = ep_desc->bEndpointAddress;
+ }
+
+ if (!(ksb->in_epAddr && ksb->out_epAddr)) {
+ pr_err("could not find bulk in and bulk out endpoints");
+ usb_put_dev(ksb->udev);
+ ksb->ifc = NULL;
+ return -ENODEV;
+ }
+
+ ksb->in_pipe = usb_rcvbulkpipe(ksb->udev, ksb->in_epAddr);
+ ksb->out_pipe = usb_sndbulkpipe(ksb->udev, ksb->out_epAddr);
+
+ usb_set_intfdata(ifc, ksb);
+ set_bit(USB_DEV_CONNECTED, &ksb->flags);
+
+ dbg_log_event(ksb, "PID-ATT", id->idProduct, 0);
+
+ fs_dev = (struct miscdevice *)id->driver_info;
+ misc_register(fs_dev);
+
+ usb_enable_autosuspend(ksb->udev);
+
+ pr_debug("usb dev connected");
+
+ return 0;
+}
+
+static int ksb_usb_suspend(struct usb_interface *ifc, pm_message_t message)
+{
+ struct ks_bridge *ksb = usb_get_intfdata(ifc);
+
+ dbg_log_event(ksb, "SUSPEND", 0, 0);
+
+ pr_info("read cnt: %d", ksb->alloced_read_pkts);
+
+ usb_kill_anchored_urbs(&ksb->submitted);
+
+ return 0;
+}
+
+static int ksb_usb_resume(struct usb_interface *ifc)
+{
+ struct ks_bridge *ksb = usb_get_intfdata(ifc);
+
+ dbg_log_event(ksb, "RESUME", 0, 0);
+
+ if (test_bit(FILE_OPENED, &ksb->flags))
+ queue_work(ksb->wq, &ksb->start_rx_work);
+
+ return 0;
+}
+
+static void ksb_usb_disconnect(struct usb_interface *ifc)
+{
+ struct ks_bridge *ksb = usb_get_intfdata(ifc);
+ unsigned long flags;
+ struct data_pkt *pkt;
+
+ dbg_log_event(ksb, "PID-DETACH", 0, 0);
+
+ clear_bit(USB_DEV_CONNECTED, &ksb->flags);
+ wake_up(&ksb->ks_wait_q);
+ cancel_work_sync(&ksb->to_mdm_work);
+
+ usb_kill_anchored_urbs(&ksb->submitted);
+
+ spin_lock_irqsave(&ksb->lock, flags);
+ while (!list_empty(&ksb->to_ks_list)) {
+ pkt = list_first_entry(&ksb->to_ks_list,
+ struct data_pkt, list);
+ list_del_init(&pkt->list);
+ ksb_free_data_pkt(pkt);
+ }
+ while (!list_empty(&ksb->to_mdm_list)) {
+ pkt = list_first_entry(&ksb->to_mdm_list,
+ struct data_pkt, list);
+ list_del_init(&pkt->list);
+ ksb_free_data_pkt(pkt);
+ }
+ spin_unlock_irqrestore(&ksb->lock, flags);
+
+ usb_put_dev(ksb->udev);
+ ksb->ifc = NULL;
+ usb_set_intfdata(ifc, NULL);
+
+ return;
+}
+
+static struct usb_driver ksb_usb_driver = {
+ .name = "ks_bridge",
+ .probe = ksb_usb_probe,
+ .disconnect = ksb_usb_disconnect,
+ .suspend = ksb_usb_suspend,
+ .resume = ksb_usb_resume,
+ .id_table = ksb_usb_ids,
+ .supports_autosuspend = 1,
+};
+
+static ssize_t ksb_debug_show(struct seq_file *s, void *unused)
+{
+ unsigned long flags;
+ struct ks_bridge *ksb = s->private;
+ int i;
+
+ read_lock_irqsave(&ksb->dbg_lock, flags);
+ for (i = 0; i < DBG_MAX_MSG; i++) {
+ if (i == (ksb->dbg_idx - 1))
+ seq_printf(s, "-->%s\n", ksb->dbgbuf[i]);
+ else
+ seq_printf(s, "%s\n", ksb->dbgbuf[i]);
+ }
+ read_unlock_irqrestore(&ksb->dbg_lock, flags);
+
+ return 0;
+}
+
+static int ksb_debug_open(struct inode *ip, struct file *fp)
+{
+ return single_open(fp, ksb_debug_show, ip->i_private);
+
+ return 0;
+}
+
+static const struct file_operations dbg_fops = {
+ .open = ksb_debug_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+static struct dentry *dbg_dir;
+static int __init ksb_init(void)
+{
+ struct ks_bridge *ksb;
+ int num_instances = 0;
+ int ret = 0;
+ int i;
+
+ dbg_dir = debugfs_create_dir("ks_bridge", NULL);
+ if (IS_ERR(dbg_dir))
+ pr_err("unable to create debug dir");
+
+ for (i = 0; i < NO_BRIDGE_INSTANCES; i++) {
+ ksb = kzalloc(sizeof(struct ks_bridge), GFP_KERNEL);
+ if (!ksb) {
+ pr_err("unable to allocat mem for ks_bridge");
+ return -ENOMEM;
+ }
+ __ksb[i] = ksb;
+
+ ksb->name = kasprintf(GFP_KERNEL, "ks_bridge:%i", i + 1);
+ if (!ksb->name) {
+ pr_info("unable to allocate name");
+ kfree(ksb);
+ ret = -ENOMEM;
+ goto dev_free;
+ }
+
+ spin_lock_init(&ksb->lock);
+ INIT_LIST_HEAD(&ksb->to_mdm_list);
+ INIT_LIST_HEAD(&ksb->to_ks_list);
+ init_waitqueue_head(&ksb->ks_wait_q);
+ ksb->wq = create_singlethread_workqueue(ksb->name);
+ if (!ksb->wq) {
+ pr_err("unable to allocate workqueue");
+ kfree(ksb->name);
+ kfree(ksb);
+ ret = -ENOMEM;
+ goto dev_free;
+ }
+
+ INIT_WORK(&ksb->to_mdm_work, ksb_tomdm_work);
+ INIT_WORK(&ksb->start_rx_work, ksb_start_rx_work);
+ init_usb_anchor(&ksb->submitted);
+
+ ksb->dbg_idx = 0;
+ ksb->dbg_lock = __RW_LOCK_UNLOCKED(lck);
+
+ if (!IS_ERR(dbg_dir))
+ debugfs_create_file(ksb->name, S_IRUGO, dbg_dir,
+ ksb, &dbg_fops);
+
+ num_instances++;
+ }
+
+ ret = usb_register(&ksb_usb_driver);
+ if (ret) {
+ pr_err("unable to register ks bridge driver");
+ goto dev_free;
+ }
+
+ pr_info("init done");
+
+ return 0;
+
+dev_free:
+ if (!IS_ERR(dbg_dir))
+ debugfs_remove_recursive(dbg_dir);
+
+ for (i = 0; i < num_instances; i++) {
+ ksb = __ksb[i];
+
+ destroy_workqueue(ksb->wq);
+ kfree(ksb->name);
+ kfree(ksb);
+ }
+
+ return ret;
+
+}
+
+static void __exit ksb_exit(void)
+{
+ struct ks_bridge *ksb;
+ int i;
+
+ if (!IS_ERR(dbg_dir))
+ debugfs_remove_recursive(dbg_dir);
+
+ usb_deregister(&ksb_usb_driver);
+
+ for (i = 0; i < NO_BRIDGE_INSTANCES; i++) {
+ ksb = __ksb[i];
+
+ destroy_workqueue(ksb->wq);
+ kfree(ksb->name);
+ kfree(ksb);
+ }
+}
+
+module_init(ksb_init);
+module_exit(ksb_exit);
+
+MODULE_DESCRIPTION(DRIVER_DESC);
+MODULE_VERSION(DRIVER_VERSION);
+MODULE_LICENSE("GPL v2");