linux 2.6下编译usb驱动和arm板进行数据通信
文件原型drivers/usb/misc/usblcd.c
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <asm/uaccess.h>
#include <linux/usb.h>
#define DRIVER_VERSION "USBLCD Driver Version 1.05"
#define USBLCD_MINOR 144
#define IOCTL_GET_HARD_VERSION 1
#define IOCTL_GET_DRV_VERSION 2
static struct usb_device_id id_table [] = {
{ .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
{ .idVendor = 0x8086, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },//gliethttp_20080527添加自己的vid
{ .idVendor = 0x1286, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },//gliethttp_20080527添加自己的vid
{ },
};
MODULE_DEVICE_TABLE (usb, id_table);
struct usb_lcd {
struct usb_device * udev; /* init: probe_lcd */
struct usb_interface * interface; /* the interface for this device */
unsigned char * bulk_in_buffer; /* the buffer to receive data */
size_t bulk_in_size; /* the size of the receive buffer */
__u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
__u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */
struct kref kref;
struct semaphore limit_sem; /* to stop writes at full throttle from
* using up all RAM */
};
#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
#define USB_LCD_CONCURRENT_WRITES 1 //gliethttp_20080527同时允许1个task控制写函数,其他task将阻塞
static struct usb_driver lcd_driver;
static DEFINE_MUTEX(usb_lcd_open_mutex);
static void lcd_delete(struct kref *kref)
{
struct usb_lcd *dev = to_lcd_dev(kref);
usb_put_dev(dev->udev);
kfree (dev->bulk_in_buffer);
kfree (dev);
}
static int lcd_open(struct inode *inode, struct file *file)
{
struct usb_lcd *dev;
struct usb_interface *interface;
int subminor;
int retval = 0;
subminor = iminor(inode);
mutex_lock(&usb_lcd_open_mutex);
interface = usb_find_interface(&lcd_driver, subminor);
if (!interface) {
err ("USBLCD: %s - error, can't find device for minor %d",
__FUNCTION__, subminor);
retval = -ENODEV;
goto exit;
}
dev = usb_get_intfdata(interface);
if (!dev) {
retval = -ENODEV;
goto exit;
}
/* increment our usage count for the device */
kref_get(&dev->kref);
/* save our object in the file's private structure */
file->private_data = dev;
exit:
mutex_unlock(&usb_lcd_open_mutex);
return retval;
}
static int lcd_release(struct inode *inode, struct file *file)
{
struct usb_lcd *dev;
dev = (struct usb_lcd *)file->private_data;
if (dev == NULL)
return -ENODEV;
/* decrement the count on our device */
kref_put(&dev->kref, lcd_delete);
return 0;
}
static ssize_t lcd_read(struct file *file, char __user * buffer, size_t count, loff_t *ppos)
{
struct usb_lcd *dev;
int retval = 0;
int bytes_read;
dev = (struct usb_lcd *)file->private_data;
/* do a blocking bulk read to get data from the device */
retval = usb_bulk_msg(dev->udev,
usb_rcvbulkpipe(dev->udev, dev->bulk_in_endpointAddr),
dev->bulk_in_buffer,
min(dev->bulk_in_size, count),
&bytes_read, 30*60*1000);//gliethttp_20080527 修改超时时间
/* if the read was successful, copy the data to userspace */
if (!retval) {
if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
retval = -EFAULT;
else
retval = bytes_read;
}
return retval;
}
static int lcd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
struct usb_lcd *dev;
u16 bcdDevice;
char buf[30];
dev = (struct usb_lcd *)file->private_data;
if (dev == NULL)
return -ENODEV;
switch (cmd) {
case IOCTL_GET_HARD_VERSION:
bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
sprintf(buf,"%1d%1d.%1d%1d",
(bcdDevice & 0xF000)>>12,
(bcdDevice & 0xF00)>>8,
(bcdDevice & 0xF0)>>4,
(bcdDevice & 0xF));
if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
return -EFAULT;
break;
case IOCTL_GET_DRV_VERSION:
sprintf(buf,DRIVER_VERSION);
if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
return -EFAULT;
break;
default:
return -ENOTTY;
break;
}
return 0;
}
static void lcd_write_bulk_callback(struct urb *urb)
{
struct usb_lcd *dev;
dev = (struct usb_lcd *)urb->context;
/* sync/async unlink faults aren't errors */
if (urb->status &&
!(urb->status == -ENOENT ||
urb->status == -ECONNRESET ||
urb->status == -ESHUTDOWN)) {
dbg("USBLCD: %s - nonzero write bulk status received: %d",
__FUNCTION__, urb->status);
}
/* free up our allocated buffer */
usb_buffer_free(urb->dev, urb->transfer_buffer_length,
urb->transfer_buffer, urb->transfer_dma);
up(&dev->limit_sem);
}
static ssize_t lcd_write(struct file *file, const char __user * user_buffer, size_t count, loff_t *ppos)
{
struct usb_lcd *dev;
int retval = 0, r;
struct urb *urb = NULL;
char *buf = NULL;
dev = (struct usb_lcd *)file->private_data;
/* verify that we actually have some data to write */
if (count == 0)
goto exit;
r = down_interruptible(&dev->limit_sem);
if (r < 0)
return -EINTR;
/* create a urb, and a buffer for it, and copy the data to the urb */
urb = usb_alloc_urb(0, GFP_KERNEL);
if (!urb) {
retval = -ENOMEM;
goto err_no_buf;
}
buf = usb_buffer_alloc(dev->udev, count, GFP_KERNEL, &urb->transfer_dma);
if (!buf) {
retval = -ENOMEM;
goto error;
}
if (copy_from_user(buf, user_buffer, count)) {
retval = -EFAULT;
goto error;
}
/* initialize the urb properly */
usb_fill_bulk_urb(urb, dev->udev,
usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
buf, count, lcd_write_bulk_callback, dev);
urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
/* send the data out the bulk port */
retval = usb_submit_urb(urb, GFP_KERNEL);
if (retval) {
err("USBLCD: %s - failed submitting write urb, error %d", __FUNCTION__, retval);
goto error;
}
/* release our reference to this urb, the USB core will eventually free it entirely */
usb_free_urb(urb);
r = down_interruptible(&dev->limit_sem);//等待，直到数据完全发送完毕
up(&dev->limit_sem);
// mdelay(10);
exit:
return count;
error:
usb_buffer_free(dev->udev, count, buf, urb->transfer_dma);
usb_free_urb(urb);
err_no_buf:
up(&dev->limit_sem);
return retval;
}
static const struct file_operations lcd_fops = {
.owner = THIS_MODULE,
.read = lcd_read,
.write = lcd_write,
.open = lcd_open,
.ioctl = lcd_ioctl,
.release = lcd_release,
};
/*
* usb class driver info in order to get a minor number from the usb core,
* and to have the device registered with the driver core
*/
static struct usb_class_driver lcd_class = {
.name = "gliethttp_flash%d",
.fops = &lcd_fops,
.minor_base = USBLCD_MINOR,
};
static int lcd_probe(struct usb_interface *interface, const struct usb_device_id *id)
{
struct usb_lcd *dev = NULL;
struct usb_host_interface *iface_desc;
struct usb_endpoint_descriptor *endpoint;
size_t buffer_size;
int i;
int retval = -ENOMEM;
/* allocate memory for our device state and initialize it */
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (dev == NULL) {
err("Out of memory");
goto error;
}
kref_init(&dev->kref);
sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
dev->udev = usb_get_dev(interface_to_usbdev(interface));
dev->interface = interface;
/*
//gliethttp_20080527
if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
warn(KERN_INFO "USBLCD model not supported.");
return -ENODEV;
}
*/
/* set up the endpoint information */
/* use only the first bulk-in and bulk-out endpoints */
iface_desc = interface->cur_altsetting;
for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
endpoint = &iface_desc->endpoint[i].desc;
if (!dev->bulk_in_endpointAddr &&
usb_endpoint_is_bulk_in(endpoint)) {
/* we found a bulk in endpoint */
buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
dev->bulk_in_size = buffer_size;
dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
if (!dev->bulk_in_buffer) {
err("Could not allocate bulk_in_buffer");
goto error;
}
}
if (!dev->bulk_out_endpointAddr &&
usb_endpoint_is_bulk_out(endpoint)) {
/* we found a bulk out endpoint */
dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
}
}
if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
err("Could not find both bulk-in and bulk-out endpoints");
goto error;
}
/* save our data pointer in this interface device */
usb_set_intfdata(interface, dev);
/* we can register the device now, as it is ready */
retval = usb_register_dev(interface, &lcd_class);
if (retval) {
/* something prevented us from registering this driver */
err("Not able to get a minor for this device.");
usb_set_intfdata(interface, NULL);
goto error;
}
i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
info("USBLCD Version %1d%1d.%1d%1d found at address %d",
(i & 0xF000)>>12,(i & 0xF00)>>8,(i & 0xF0)>>4,(i & 0xF),
dev->udev->devnum);
/* let the user know what node this device is now attached to */
info("USB LCD device now attached to USBLCD-%d", interface->minor);
return 0;
error:
if (dev)
kref_put(&dev->kref, lcd_delete);
return retval;
}
static void lcd_disconnect(struct usb_interface *interface)
{
struct usb_lcd *dev;
int minor = interface->minor;
/* prevent skel_open() from racing skel_disconnect() */
mutex_lock(&usb_lcd_open_mutex);
dev = usb_get_intfdata(interface);
usb_set_intfdata(interface, NULL);
/* give back our minor */
usb_deregister_dev(interface, &lcd_class);
mutex_unlock(&usb_lcd_open_mutex);
/* decrement our usage count */
kref_put(&dev->kref, lcd_delete);
info("USB LCD #%d now disconnected", minor);
}
static struct usb_driver lcd_driver = {
.name = "usblcd",
.probe = lcd_probe,
.disconnect = lcd_disconnect,
.id_table = id_table,
};
static int __init usb_lcd_init(void)
{
int result;
result = usb_register(&lcd_driver);
if (result)
err("usb_register failed. Error number %d", result);
return result;
}
static void __exit usb_lcd_exit(void)
{
usb_deregister(&lcd_driver);
}
module_init(usb_lcd_init);
module_exit(usb_lcd_exit);
MODULE_AUTHOR("Georges Toth ");
MODULE_DESCRIPTION(DRIVER_VERSION);
MODULE_LICENSE("GPL");
luther@gliethttp:~/work/kernel/module_drivers/gliethttp_flash$ echo "obj-m:=gliethttp_flash.o" > Makefile
luther@gliethttp:~/work/kernel/module_drivers/gliethttp_flash$ make -C /lib/modules/`uname -r`/build M=`pwd` modules
make: Entering directory `/usr/src/linux-headers-2.6.22-14-generic'
CC [M] /home/luther/work/kernel/module_drivers/gliethttp_flash/gliethttp_flash.o
Building modules, stage 2.
MODPOST 1 modules
CC /home/luther/work/kernel/module_drivers/gliethttp_flash/gliethttp_flash.mod.o
LD [M] /home/luther/work/kernel/module_drivers/gliethttp_flash/gliethttp_flash.ko
make: Leaving directory `/usr/src/linux-headers-2.6.22-14-generic'
luther@gliethttp:~/work/kernel/module_drivers/gliethttp_flash$
luther@gliethttp:~/work/kernel/module_drivers/gliethttp_flash$ ls /dev/gliethttp_flash0
/dev/gliethttp_flash0
luther@gliethttp:~/work/kernel/module_drivers/gliethttp_flash$
但是和libusb-0.1.12一样,在
Intel处理器（DELL OptiPlex 330) 不支持AMD处理器（DELL OptiPlex 740)主板上ubuntu出现不稳定现象，在
AMD处理器（DELL OptiPlex 740) 不支持Intel处理器（DELL OptiPlex 330)主板上表现出色，
如果这样来看的话，只能说ubuntu在DELL OptiPlex 330主板usb驱动模块不稳定了，但是
在DELL OptiPlex 330上对u盘进行数据操作一切正常，具体不清楚到底是咋回事，唉！！！
[注：很有可能DELL OptiPlex 330上usb数据传输速度太快，下面arm板上的驱动对于快速数据传输反应不过来，但是加入mdelay(10)进行10ms延时之后，仍然出现同样的问题，所以80％问题是ubuntu在DELL OptiPlex 330主板上不稳定！]
ps：可以肯定的是pc确实已经把通信数据发送下去了,在调用read的时候,一直不能等到设备返回应该返回的状态信息，协议上可能不存在丢包后数据重发
机制，所以可能确实是因为pc下发的数据包丢失了，所以设备端因为没有收到数据,以及校验包完整性措施，进而，不能和tcp/ip数据传输那样有很好的容
错能力，看来marvell设计的这个通信不成熟阿，
所以在协议设计上，对丢包处理、数据干扰后的校验重传机制等对任何产品来说不是必要的，而是必须的，所以文件切包之后进行包序号标记是很有意义的,可以参考成熟的tcp/ip数据传输、校验、重传等方式！[gliethttp_20080529]
ps：
所以从这里来看,所谓的设备通信不稳定，就是在于设备对丢包和误码处理不完善，虽然bulk类型端口的通信能够保证数据传输正确性，但是不能保证因为线路
干扰严重或者系统自身的问题超过bulk内定的重试次数之后引起的丢包现象！[gliethttp_20080529]
|
