Hello

Could yout point me a reason why grabbing datas from usb device these datas
includes some incorrect numbers ? Is it synchronization or what ??

I put it in my endpoint2 fifo buffer incrementing datas ( from 1 to 64).
I wrote a device driver and I use it to read these datas from.

I insert fragment of my device driver .. please tell me what I'm doing wrong
?

frame_size = 64 .
endpoint_r =  82H .

static ssize_t fx2_read (struct file *file, char *buf, size_t count, loff_t
*ppos)
{
if ( buffersNotAllocated ) AllocateBuffers();            //these are my
defined functions
ssize_t retval = 0 ;
sRead.nOffset = 0;
retval=usb_bulk_msg (my_dev, usb_rcvbulkpipe
(my_dev,endpoint_r),sRead.pBuff, frame_size, &count, HZ*5);
 wait_for_urb (sRead.pUrb);

 sRead.nLeft = sRead.pUrb->actual_length;

 /* if the read was successful =0 , copy the data to userspace */
 if (!retval) {
    if (copy_to_user (buf, sRead.pBuff, sRead.nLeft))
           retval = -EFAULT;
 else{
   retval = count;
      }
  }
}



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