2023-05-04 11:47:21 +08:00

786 lines
18 KiB
C

/* Copyright (c) 2018, 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.
*/
#include <linux/cdev.h>
#include <linux/device.h>
#include <linux/dma-direction.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/poll.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/uaccess.h>
#include <linux/tty.h>
#include "../core/mhi.h"
#define DEVICE_NAME "mhi"
#define MHI_UCI_DRIVER_NAME "mhi_uci"
struct uci_chan {
wait_queue_head_t wq;
spinlock_t lock;
struct list_head pending; /* user space waiting to read */
struct uci_buf *cur_buf; /* current buffer user space reading */
size_t rx_size;
};
struct uci_buf {
void *data;
size_t len;
struct list_head node;
};
struct uci_dev {
struct list_head node;
dev_t devt;
struct device *dev;
struct mhi_device *mhi_dev;
const char *chan;
struct mutex mutex; /* sync open and close */
struct uci_chan ul_chan;
struct uci_chan dl_chan;
size_t mtu;
int ref_count;
bool enabled;
bool disconnect;
struct ktermios termios;
int sigs;
};
struct mhi_uci_drv {
struct list_head head;
struct mutex lock;
struct class *class;
int major;
dev_t dev_t;
};
enum MHI_DEBUG_LEVEL msg_lvl = MHI_MSG_LVL_ERROR;
typedef struct _QCQMI_HDR {
u8 IFType;
u16 Length;
u8 CtlFlags; // reserved
u8 QMIType;
u8 ClientId;
} __attribute__ ((packed)) *PQCQMI_HDR;
#define MSG_VERB(fmt, ...) do { \
if (msg_lvl <= MHI_MSG_LVL_VERBOSE) \
pr_err("[D][%s] " fmt, __func__, ##__VA_ARGS__); \
} while (0)
#define MSG_LOG(fmt, ...) do { \
if (msg_lvl <= MHI_MSG_LVL_INFO) \
pr_err("[I][%s] " fmt, __func__, ##__VA_ARGS__); \
} while (0)
#define MSG_ERR(fmt, ...) do { \
if (msg_lvl <= MHI_MSG_LVL_ERROR) \
pr_err("[E][%s] " fmt, __func__, ##__VA_ARGS__); \
} while (0)
#define MAX_UCI_DEVICES (64)
#define QUEC_MHI_UCI_ALWAYS_OPEN //by now, sdx20 can not handle "start-reset-start" operation, so the simply solution is keep start state
static DECLARE_BITMAP(uci_minors, MAX_UCI_DEVICES);
static struct mhi_uci_drv mhi_uci_drv;
static int mhi_queue_inbound(struct uci_dev *uci_dev)
{
struct mhi_device *mhi_dev = uci_dev->mhi_dev;
int nr_trbs = mhi_get_no_free_descriptors(mhi_dev, DMA_FROM_DEVICE);
size_t mtu = uci_dev->mtu;
void *buf;
struct uci_buf *uci_buf;
int ret = -EIO, i;
for (i = 0; i < nr_trbs; i++) {
buf = kmalloc(mtu + sizeof(*uci_buf), GFP_KERNEL);
if (!buf)
return -ENOMEM;
uci_buf = buf + mtu;
uci_buf->data = buf;
MSG_VERB("Allocated buf %d of %d size %zd\n", i, nr_trbs, mtu);
ret = mhi_queue_transfer(mhi_dev, DMA_FROM_DEVICE, buf, mtu,
MHI_EOT);
if (ret) {
kfree(buf);
MSG_ERR("Failed to queue buffer %d\n", i);
return ret;
}
}
return ret;
}
static long mhi_uci_ioctl(struct file *file,
unsigned int cmd,
unsigned long arg)
{
struct uci_dev *uci_dev = file->private_data;
struct mhi_device *mhi_dev = uci_dev->mhi_dev;
long ret = -ERESTARTSYS;
mutex_lock(&uci_dev->mutex);
if (uci_dev->enabled) {
switch (cmd) {
case TCGETS:
#ifndef TCGETS2
ret = kernel_termios_to_user_termios((struct termios __user *)arg, &uci_dev->termios);
#else
ret = kernel_termios_to_user_termios_1((struct termios __user *)arg, &uci_dev->termios);
#endif
break;
case TCSETSF:
case TCSETS:
#ifndef TCGETS2
ret = user_termios_to_kernel_termios(&uci_dev->termios, (struct termios __user *)arg);
#else
ret = user_termios_to_kernel_termios_1(&uci_dev->termios, (struct termios __user *)arg);
#endif
break;
case TIOCMSET:
case TIOCMBIS:
case TIOCMBIC:
{
uint32_t val;
ret = get_user(val, (uint32_t *)arg);
if (ret)
return ret;
switch (cmd) {
case TIOCMBIS:
uci_dev->sigs |= val;
break;
case TIOCMBIC:
uci_dev->sigs &= ~val;
break;
case TIOCMSET:
uci_dev->sigs = val;
break;
}
}
break;
case TIOCMGET:
ret = put_user(uci_dev->sigs | TIOCM_RTS, (uint32_t *)arg);
break;
case TCFLSH:
ret = 0;
break;
default:
ret = mhi_ioctl(mhi_dev, cmd, arg);
break;
}
}
mutex_unlock(&uci_dev->mutex);
return ret;
}
static int mhi_uci_release(struct inode *inode, struct file *file)
{
struct uci_dev *uci_dev = file->private_data;
mutex_lock(&uci_dev->mutex);
uci_dev->ref_count--;
if (!uci_dev->ref_count) {
struct uci_buf *itr, *tmp;
struct uci_chan *uci_chan;
MSG_LOG("Last client left, closing node\n");
if (uci_dev->enabled)
mhi_unprepare_from_transfer(uci_dev->mhi_dev);
/* clean inbound channel */
uci_chan = &uci_dev->dl_chan;
list_for_each_entry_safe(itr, tmp, &uci_chan->pending, node) {
list_del(&itr->node);
kfree(itr->data);
}
if (uci_chan->cur_buf)
kfree(uci_chan->cur_buf->data);
uci_chan->cur_buf = NULL;
if (!uci_dev->enabled) {
MSG_LOG("Node is deleted, freeing dev node\n");
mutex_unlock(&uci_dev->mutex);
mutex_destroy(&uci_dev->mutex);
clear_bit(MINOR(uci_dev->devt), uci_minors);
kfree(uci_dev);
return 0;
}
}
mutex_unlock(&uci_dev->mutex);
MSG_LOG("exit: ref_count:%d\n", uci_dev->ref_count);
return 0;
}
static unsigned int mhi_uci_poll(struct file *file, poll_table *wait)
{
struct uci_dev *uci_dev = file->private_data;
struct mhi_device *mhi_dev = uci_dev->mhi_dev;
struct uci_chan *uci_chan;
unsigned int mask = 0;
poll_wait(file, &uci_dev->dl_chan.wq, wait);
poll_wait(file, &uci_dev->ul_chan.wq, wait);
uci_chan = &uci_dev->dl_chan;
spin_lock_bh(&uci_chan->lock);
if (!uci_dev->enabled) {
mask = POLLERR;
} else if (!list_empty(&uci_chan->pending) || uci_chan->cur_buf) {
MSG_VERB("Client can read from node\n");
mask |= POLLIN | POLLRDNORM;
}
spin_unlock_bh(&uci_chan->lock);
uci_chan = &uci_dev->ul_chan;
spin_lock_bh(&uci_chan->lock);
if (!uci_dev->enabled) {
mask |= POLLERR;
} else if (mhi_get_no_free_descriptors(mhi_dev, DMA_TO_DEVICE) > 0) {
MSG_VERB("Client can write to node\n");
mask |= POLLOUT | POLLWRNORM;
}
if (uci_dev->disconnect)
mask |= POLLHUP;
spin_unlock_bh(&uci_chan->lock);
MSG_VERB("Client attempted to poll, returning mask 0x%x\n", mask);
return mask;
}
static ssize_t mhi_uci_write(struct file *file,
const char __user *buf,
size_t count,
loff_t *offp)
{
struct uci_dev *uci_dev = file->private_data;
struct mhi_device *mhi_dev = uci_dev->mhi_dev;
struct uci_chan *uci_chan = &uci_dev->ul_chan;
size_t bytes_xfered = 0;
int ret;
if (!buf || !count)
return -EINVAL;
/* confirm channel is active */
spin_lock_bh(&uci_chan->lock);
if (!uci_dev->enabled) {
spin_unlock_bh(&uci_chan->lock);
return -ERESTARTSYS;
}
MSG_VERB("Enter: to xfer:%zd bytes\n", count);
while (count) {
size_t xfer_size;
void *kbuf;
enum MHI_FLAGS flags;
spin_unlock_bh(&uci_chan->lock);
if (mhi_get_no_free_descriptors(mhi_dev, DMA_TO_DEVICE) == 0 && (file->f_mode & FMODE_NDELAY))
break;
/* wait for free descriptors */
ret = wait_event_interruptible(uci_chan->wq,
(!uci_dev->enabled) ||
mhi_get_no_free_descriptors
(mhi_dev, DMA_TO_DEVICE) > 0);
if (ret == -ERESTARTSYS) {
MSG_LOG("Exit signal caught for node\n");
return -ERESTARTSYS;
}
xfer_size = min_t(size_t, count, uci_dev->mtu);
kbuf = kmalloc(xfer_size, GFP_KERNEL);
if (!kbuf) {
MSG_ERR("Failed to allocate memory %zd\n", xfer_size);
return -ENOMEM;
}
ret = copy_from_user(kbuf, buf, xfer_size);
if (unlikely(ret)) {
kfree(kbuf);
return ret;
}
spin_lock_bh(&uci_chan->lock);
flags = MHI_EOT;
if (uci_dev->enabled)
ret = mhi_queue_transfer(mhi_dev, DMA_TO_DEVICE, kbuf,
xfer_size, flags);
else
ret = -ERESTARTSYS;
if (ret) {
kfree(kbuf);
goto sys_interrupt;
}
bytes_xfered += xfer_size;
count -= xfer_size;
buf += xfer_size;
}
spin_unlock_bh(&uci_chan->lock);
MSG_VERB("Exit: Number of bytes xferred:%zd\n", bytes_xfered);
return bytes_xfered;
sys_interrupt:
spin_unlock_bh(&uci_chan->lock);
return ret;
}
static ssize_t mhi_uci_read(struct file *file,
char __user *buf,
size_t count,
loff_t *ppos)
{
struct uci_dev *uci_dev = file->private_data;
struct mhi_device *mhi_dev = uci_dev->mhi_dev;
struct uci_chan *uci_chan = &uci_dev->dl_chan;
struct uci_buf *uci_buf;
char *ptr;
size_t to_copy;
int ret = 0;
if (!buf)
return -EINVAL;
MSG_VERB("Client provided buf len:%zd\n", count);
/* confirm channel is active */
spin_lock_bh(&uci_chan->lock);
if (!uci_dev->enabled) {
spin_unlock_bh(&uci_chan->lock);
return -ERESTARTSYS;
}
/* No data available to read, wait */
if (!uci_chan->cur_buf && list_empty(&uci_chan->pending)) {
MSG_VERB("No data available to read waiting\n");
spin_unlock_bh(&uci_chan->lock);
if (file->f_mode & FMODE_NDELAY)
return -EAGAIN;
ret = wait_event_interruptible(uci_chan->wq,
(!uci_dev->enabled ||
!list_empty(&uci_chan->pending)));
if (ret == -ERESTARTSYS) {
MSG_LOG("Exit signal caught for node\n");
return -ERESTARTSYS;
}
spin_lock_bh(&uci_chan->lock);
if (!uci_dev->enabled) {
MSG_LOG("node is disabled\n");
ret = -ERESTARTSYS;
goto read_error;
}
}
/* new read, get the next descriptor from the list */
if (!uci_chan->cur_buf) {
uci_buf = list_first_entry_or_null(&uci_chan->pending,
struct uci_buf, node);
if (unlikely(!uci_buf)) {
ret = -EIO;
goto read_error;
}
list_del(&uci_buf->node);
uci_chan->cur_buf = uci_buf;
uci_chan->rx_size = uci_buf->len;
MSG_VERB("Got pkt of size:%zd\n", uci_chan->rx_size);
}
uci_buf = uci_chan->cur_buf;
spin_unlock_bh(&uci_chan->lock);
/* Copy the buffer to user space */
to_copy = min_t(size_t, count, uci_chan->rx_size);
ptr = uci_buf->data + (uci_buf->len - uci_chan->rx_size);
ret = copy_to_user(buf, ptr, to_copy);
if (ret)
return ret;
MSG_VERB("Copied %zd of %zd bytes\n", to_copy, uci_chan->rx_size);
uci_chan->rx_size -= to_copy;
/* we finished with this buffer, queue it back to hardware */
if (!uci_chan->rx_size) {
spin_lock_bh(&uci_chan->lock);
uci_chan->cur_buf = NULL;
if (uci_dev->enabled)
ret = mhi_queue_transfer(mhi_dev, DMA_FROM_DEVICE,
uci_buf->data, uci_dev->mtu,
MHI_EOT);
else
ret = -ERESTARTSYS;
if (ret) {
MSG_ERR("Failed to recycle element\n");
kfree(uci_buf->data);
goto read_error;
}
spin_unlock_bh(&uci_chan->lock);
}
MSG_VERB("Returning %zd bytes\n", to_copy);
return to_copy;
read_error:
spin_unlock_bh(&uci_chan->lock);
return ret;
}
static int mhi_uci_open(struct inode *inode, struct file *filp)
{
struct uci_dev *uci_dev;
int ret = -EIO;
struct uci_buf *buf_itr, *tmp;
struct uci_chan *dl_chan;
mutex_lock(&mhi_uci_drv.lock);
list_for_each_entry(uci_dev, &mhi_uci_drv.head, node) {
if (uci_dev->devt == inode->i_rdev) {
ret = 0;
break;
}
}
mutex_unlock(&mhi_uci_drv.lock);
/* could not find a minor node */
if (ret)
return ret;
mutex_lock(&uci_dev->mutex);
if (!uci_dev->enabled) {
MSG_ERR("Node exist, but not in active state!\n");
goto error_open_chan;
}
uci_dev->ref_count++;
MSG_LOG("Node open, ref counts %u\n", uci_dev->ref_count);
if (uci_dev->ref_count == 1) {
MSG_LOG("Starting channel\n");
ret = mhi_prepare_for_transfer(uci_dev->mhi_dev);
if (ret) {
MSG_ERR("Error starting transfer channels\n");
uci_dev->ref_count--;
goto error_open_chan;
}
ret = mhi_queue_inbound(uci_dev);
if (ret)
goto error_rx_queue;
#ifdef QUEC_MHI_UCI_ALWAYS_OPEN
uci_dev->ref_count++;
if (uci_dev->mhi_dev->dl_chan_id == MHI_CLIENT_QMI_IN) {
}
if (uci_dev->mhi_dev->dl_chan_id == MHI_CLIENT_MBIM_IN) {
}
#endif
}
filp->private_data = uci_dev;
mutex_unlock(&uci_dev->mutex);
return 0;
error_rx_queue:
dl_chan = &uci_dev->dl_chan;
mhi_unprepare_from_transfer(uci_dev->mhi_dev);
list_for_each_entry_safe(buf_itr, tmp, &dl_chan->pending, node) {
list_del(&buf_itr->node);
kfree(buf_itr->data);
}
error_open_chan:
mutex_unlock(&uci_dev->mutex);
return ret;
}
static const struct file_operations mhidev_fops = {
.open = mhi_uci_open,
.release = mhi_uci_release,
.read = mhi_uci_read,
.write = mhi_uci_write,
.poll = mhi_uci_poll,
.unlocked_ioctl = mhi_uci_ioctl,
};
static void mhi_uci_remove(struct mhi_device *mhi_dev)
{
struct uci_dev *uci_dev = mhi_device_get_devdata(mhi_dev);
MSG_LOG("Enter\n");
/* disable the node */
mutex_lock(&uci_dev->mutex);
spin_lock_irq(&uci_dev->dl_chan.lock);
spin_lock_irq(&uci_dev->ul_chan.lock);
uci_dev->enabled = false;
uci_dev->disconnect = true;
spin_unlock_irq(&uci_dev->ul_chan.lock);
spin_unlock_irq(&uci_dev->dl_chan.lock);
wake_up(&uci_dev->dl_chan.wq);
wake_up(&uci_dev->ul_chan.wq);
/* delete the node to prevent new opens */
device_destroy(mhi_uci_drv.class, uci_dev->devt);
uci_dev->dev = NULL;
mutex_lock(&mhi_uci_drv.lock);
list_del(&uci_dev->node);
mutex_unlock(&mhi_uci_drv.lock);
#ifdef QUEC_MHI_UCI_ALWAYS_OPEN
if (uci_dev->ref_count > 0)
uci_dev->ref_count--;
#endif
/* safe to free memory only if all file nodes are closed */
if (!uci_dev->ref_count) {
mutex_unlock(&uci_dev->mutex);
mutex_destroy(&uci_dev->mutex);
clear_bit(MINOR(uci_dev->devt), uci_minors);
kfree(uci_dev);
return;
}
mutex_unlock(&uci_dev->mutex);
MSG_LOG("Exit\n");
}
static int mhi_uci_probe(struct mhi_device *mhi_dev,
const struct mhi_device_id *id)
{
struct uci_dev *uci_dev;
int minor;
int dir;
uci_dev = kzalloc(sizeof(*uci_dev), GFP_KERNEL);
if (!uci_dev)
return -ENOMEM;
mutex_init(&uci_dev->mutex);
uci_dev->mhi_dev = mhi_dev;
minor = find_first_zero_bit(uci_minors, MAX_UCI_DEVICES);
if (minor >= MAX_UCI_DEVICES) {
kfree(uci_dev);
return -ENOSPC;
}
mutex_lock(&uci_dev->mutex);
mutex_lock(&mhi_uci_drv.lock);
uci_dev->devt = MKDEV(mhi_uci_drv.major, minor);
uci_dev->dev = device_create(mhi_uci_drv.class, &mhi_dev->dev,
uci_dev->devt, uci_dev,
DEVICE_NAME "_%s",
mhi_dev->chan_name);
set_bit(minor, uci_minors);
for (dir = 0; dir < 2; dir++) {
struct uci_chan *uci_chan = (dir) ?
&uci_dev->ul_chan : &uci_dev->dl_chan;
spin_lock_init(&uci_chan->lock);
init_waitqueue_head(&uci_chan->wq);
INIT_LIST_HEAD(&uci_chan->pending);
};
uci_dev->termios = tty_std_termios;
uci_dev->sigs = 0;
uci_dev->mtu = id->driver_data;
mhi_device_set_devdata(mhi_dev, uci_dev);
uci_dev->enabled = true;
list_add(&uci_dev->node, &mhi_uci_drv.head);
mutex_unlock(&mhi_uci_drv.lock);
mutex_unlock(&uci_dev->mutex);
MSG_LOG("channel:%s successfully probed\n", mhi_dev->chan_name);
return 0;
};
static void mhi_ul_xfer_cb(struct mhi_device *mhi_dev,
struct mhi_result *mhi_result)
{
struct uci_dev *uci_dev = mhi_device_get_devdata(mhi_dev);
struct uci_chan *uci_chan = &uci_dev->ul_chan;
MSG_VERB("status:%d xfer_len:%zu\n", mhi_result->transaction_status,
mhi_result->bytes_xferd);
kfree(mhi_result->buf_addr);
if (!mhi_result->transaction_status)
wake_up(&uci_chan->wq);
}
static void mhi_dl_xfer_cb(struct mhi_device *mhi_dev,
struct mhi_result *mhi_result)
{
struct uci_dev *uci_dev = mhi_device_get_devdata(mhi_dev);
struct uci_chan *uci_chan = &uci_dev->dl_chan;
unsigned long flags;
struct uci_buf *buf;
MSG_VERB("chan:mhi_dev->dl_chan_id:%d, status:%d receive_len:%zu\n",
mhi_dev->dl_chan_id, mhi_result->transaction_status, mhi_result->bytes_xferd);
if (mhi_result->transaction_status == -ENOTCONN) {
kfree(mhi_result->buf_addr);
return;
}
spin_lock_irqsave(&uci_chan->lock, flags);
buf = mhi_result->buf_addr + uci_dev->mtu;
if (buf->data != mhi_result->buf_addr) {
MSG_LOG("%p, %p\n", buf->data, mhi_result->buf_addr);
}
buf->data = mhi_result->buf_addr;
buf->len = mhi_result->bytes_xferd;
if (uci_dev->mhi_dev->dl_chan_id == MHI_CLIENT_QMI_IN) {
PQCQMI_HDR pHdr = (PQCQMI_HDR) (buf->data);
u16 qmiLength = (le16_to_cpu(pHdr->Length) + 1);
// open qmi chan, but not read data from the chan, will cause next error, donot know why by now, so it is not recomment to use uqmi&libqmi?
// dmesg -c > /dev/null; echo 1 > /dev/mhi_QMI0; sleep 3; ./FIBO-CM -d /dev/mhi_QMI0 -v
if (qmiLength != buf->len) {
unsigned char *d = (unsigned char *) pHdr;
MSG_ERR("bytes_xferd=%zd, qmiLength=%d %02x%02x%02x%02x - %02x%02x%02x%02x\n", buf->len, qmiLength,
d[0],d[1],d[2],d[3],d[qmiLength+0],d[qmiLength+1],d[qmiLength+2],d[qmiLength+3]);
if (buf->len > qmiLength)
buf->len = qmiLength;
}
}
list_add_tail(&buf->node, &uci_chan->pending);
spin_unlock_irqrestore(&uci_chan->lock, flags);
wake_up(&uci_chan->wq);
}
#define DIAG_MAX_PCIE_PKT_SZ 2048 //define by module
/* .driver_data stores max mtu */
static const struct mhi_device_id mhi_uci_match_table[] = {
{ .chan = "LOOPBACK", .driver_data = 0x1000 },
{ .chan = "SAHARA", .driver_data = 0x4000 },
{ .chan = "EDL", .driver_data = 0x4000 },
{ .chan = "DIAG", .driver_data = DIAG_MAX_PCIE_PKT_SZ },
{ .chan = "EFS", .driver_data = 0x1000 },
#ifdef CONFIG_MHI_NETDEV_MBIM
{ .chan = "MBIM", .driver_data = 0x1000 },
#else
{ .chan = "QMI0", .driver_data = 0x1000 },
{ .chan = "QMI1", .driver_data = 0x1000 },
#endif
{ .chan = "TF", .driver_data = 0x1000 },
{ .chan = "BL", .driver_data = 0x1000 },
{ .chan = "DUN", .driver_data = 0x1000 },
{ .chan = "GNSS", .driver_data = 0x1000 },
{ .chan = "AUDIO", .driver_data = 0x1000 },
{ },
};
static struct mhi_driver mhi_uci_driver = {
.id_table = mhi_uci_match_table,
.remove = mhi_uci_remove,
.probe = mhi_uci_probe,
.ul_xfer_cb = mhi_ul_xfer_cb,
.dl_xfer_cb = mhi_dl_xfer_cb,
.driver = {
.name = MHI_UCI_DRIVER_NAME,
.owner = THIS_MODULE,
},
};
int mhi_device_uci_init(void)
{
int ret;
ret = register_chrdev(0, MHI_UCI_DRIVER_NAME, &mhidev_fops);
if (ret < 0)
return ret;
mhi_uci_drv.major = ret;
mhi_uci_drv.class = class_create(THIS_MODULE, MHI_UCI_DRIVER_NAME);
if (IS_ERR(mhi_uci_drv.class)) {
unregister_chrdev(mhi_uci_drv.major, MHI_UCI_DRIVER_NAME);
return -ENODEV;
}
mutex_init(&mhi_uci_drv.lock);
INIT_LIST_HEAD(&mhi_uci_drv.head);
ret = mhi_driver_register(&mhi_uci_driver);
if (ret) {
class_destroy(mhi_uci_drv.class);
unregister_chrdev(mhi_uci_drv.major, MHI_UCI_DRIVER_NAME);
}
return ret;
}
void mhi_device_uci_exit(void)
{
mhi_driver_unregister(&mhi_uci_driver);
class_destroy(mhi_uci_drv.class);
unregister_chrdev(mhi_uci_drv.major, MHI_UCI_DRIVER_NAME);
}