usb-c2420eb.c

实现IEEE802。15。4协议的开发板的USB驱动

	/* verify that we actually have some data to write */
	if (count == 0) 
	{
		dbg(__FUNCTION__ " - write request of 0 bytes");
		goto exit;
	}

	/* see if we are already in the middle of a write */
	if (dev->write_urb->status == -EINPROGRESS) 
	{
		dbg (__FUNCTION__ " - already writing");
		goto exit;
	}

	/* we can only write as much as 1 urb will hold */
	bytes_written = (count > dev->bulk_out_size) ? 
				dev->bulk_out_size : count;

	/* copy the data from userspace into our urb */
	if (copy_from_user(dev->write_urb->transfer_buffer, buffer, 
			   bytes_written)) 
	{
		retval = -EFAULT;
		goto exit;
	}

	c2420eb_debug_data (__FUNCTION__, bytes_written, 
			     dev->write_urb->transfer_buffer);

	/* set up our urb */
	FILL_BULK_URB(dev->write_urb, dev->udev, 
		      usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
		      dev->write_urb->transfer_buffer, bytes_written,
		      c2420eb_write_bulk_callback, dev);

	/* send the data out the bulk port */
	retval = usb_submit_urb(dev->write_urb);
	if (retval) 
	{
		err(__FUNCTION__ " - failed submitting write urb, error %d",
		    retval);
	} 
	else 
		retval = bytes_written;

exit:
	/* unlock the device */
	up (&dev->sem);

	return retval;
}


/**
 * c2420eb_ioctl
 * Function performs ioctl function call
 * Param: inode - special file inode description
 * Param: file - file description
 * Param: cmd - ioctl command
 * Param: arg - argument
 * Return 0 on success, -<error code> on error
 */
static int c2420eb_ioctl (struct inode* inode, struct file* file, 
	unsigned int cmd, unsigned long arg)
{
	struct c2420eb* dev; //device descriptor
	int retval; //function return value
	__u16 chan; //channel number
	__u16 reg; //register we read/write
	
	dev = (struct c2420eb*)file->private_data;

	if (_IOC_TYPE(cmd) != ZB_MAGIC) 
		return -ENOTTY;
	
	/* lock this object */
	down (&dev->sem);

	/* verify that the device wasn't unplugged */
	if (dev->udev == NULL) 
	{
		up (&dev->sem);
		return -ENODEV;
	}

	dbg(__FUNCTION__ " - minor %d, cmd 0x%.4x, arg %ld", 
	    dev->minor, cmd, arg);

	switch (cmd)
	{
		case CC2420_TRX_OFF:
		{
			retval = c2420eb_trxOff(dev);
			break;
		}
		case CC2420_SET_CHANNEL:
		{
			retval = __get_user(chan, (__u16*)arg);
			if (retval != 0)
				retval = -EFAULT;
			else
			{
				retval = c2420eb_setCahnnel(dev, chan);
				if ((retval = c2420_submitReadUrb(dev, 0)) < 0)
				{
					err("Open: unable submit URB %d", retval);
					up (&dev->sem);
					return -EIO;
				}
				else
				{
					dbg("Submit buffer %d", dev->writeIdx);
				}
			}
			break;
		}
		case CC2420_SET_MODULATION:
		{
			retval = __get_user(chan, (__u16*)arg);
			if (retval != 0)
				retval = -EFAULT;
			else 
			{
				retval = c2420eb_readReg(dev, MDMCTRL1, &reg);
				if (retval < 0)
					break;
				if (chan != 0)
					reg |= MODULATION_REVERSED;
				else
					reg &= ~MODULATION_REVERSED;
	
				retval = c2420eb_writeReg(dev, MDMCTRL1, reg);
				if (retval < 0)
					break;
			}
			break;
		}
		default:
		{
			retval = -ENOTTY;
			break;
		}
	}

	/* fill in your device specific stuff here */

	/* unlock the device */
	up (&dev->sem);
	
	/* return that we did not understand this ioctl call */
	return retval;
}


/**
 *	c2420eb_write_bulk_callback
 */
static void c2420eb_write_bulk_callback (struct urb* urb)
{
	struct c2420eb* dev = (struct c2420eb*)urb->context;

	dbg(__FUNCTION__ " - minor %d", dev->minor);

	if ((urb->status != -ENOENT) && 
	    (urb->status != -ECONNRESET)) 
	{
		dbg(__FUNCTION__ " - nonzero write bulk status received: %d",
		    urb->status);
		return;
	}

	return;
}


/**
 *	c2420eb_probe
 *
 *	Called by the usb core when a new device is connected that it thinks
 *	this driver might be interested in.
 */
static void * c2420eb_probe(struct usb_device* udev, unsigned int ifnum, 
	const struct usb_device_id* id)
{
	struct c2420eb *dev = NULL;
	struct usb_interface *interface;
	struct usb_interface_descriptor *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	int minor;
	int buffer_size;
	
	int i;
	char name[10];
	bool loadFirmware; //if we are loading firmware
	
	
	/* See if the device offered us matches what we can accept */
	if ((udev->descriptor.idVendor != C2420EB_VENDOR_ID) ||
	   ((udev->descriptor.idProduct != C2420EB_PRODUCT_ID) && 
		 	udev->descriptor.idProduct != C2420EB_PRODUCT_ID1)) {
		return NULL;
	}
	
	if (udev->descriptor.idProduct == C2420EB_PRODUCT_ID)
		loadFirmware = TRUE;
	else
		loadFirmware = FALSE;

	/* select a "subminor" number (part of a minor number) */
	down (&minor_table_mutex);
	for (minor = 0; minor < MAX_DEVICES; ++minor) {
		if (minor_table[minor] == NULL)
			break;
	}
	if (minor >= MAX_DEVICES) {
		info ("Too many devices plugged in, can not handle this device.");
		goto exit;
	}

	/* allocate memory for our device state and intialize it */
	dev = kmalloc (sizeof(struct c2420eb), GFP_KERNEL);
	if (dev == NULL) {
		err ("Out of memory");
		goto exit;
	}
	memset (dev, 0x00, sizeof (*dev));
	minor_table[minor] = dev;

	interface = &udev->actconfig->interface[ifnum];

	init_MUTEX (&dev->sem);
	dev->udev = udev;
	dev->interface = interface;
	dev->minor = minor;
	dev->readBufSize = sizeof(dev->read_buffer) / sizeof(struct RdBuf);
	init_waitqueue_head (&dev->readwq);
	spin_lock_init(&dev->readLock);

	/* set up the endpoint information */
	/* check out the endpoints */
	if (loadFirmware)
		iface_desc = &interface->altsetting[1];
	else 
		iface_desc = &interface->altsetting[0];

	for (i = 0; i < iface_desc->bNumEndpoints; ++i) 
	{
		endpoint = &iface_desc->endpoint[i];
		if (endpoint->bEndpointAddress == PACKET_READ_PIPE) 
		{
			dev->readLen = endpoint->wMaxPacketSize;
			dbg("Max packet length for read operations - %d", dev->readLen);
		}
		
		if ((endpoint->bEndpointAddress & 0x80) &&
		    ((endpoint->bmAttributes & 3) == 0x02) && 
				dev->bulk_in_size < endpoint->wMaxPacketSize)
		{
			if (!loadFirmware && !dev->read_urb)
			{
				dev->read_urb = usb_alloc_urb(0);
				if (!dev->read_urb) {
					err("No free urbs available");
					goto error;
				}
				dbg("Allocate read URB %p", dev->read_urb);
			}
			/* we found a bulk in endpoint */
			buffer_size = endpoint->wMaxPacketSize;
			dev->bulk_in_size = buffer_size;
			dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
			dbg("Allocate %d bytes for IN endpoint 0x%x", dev->bulk_in_size,
				endpoint->bEndpointAddress);
		}
		
		if (((endpoint->bEndpointAddress & 0x80) == 0x00) &&
		    ((endpoint->bmAttributes & 3) == 0x02) &&
				dev->bulk_out_size < endpoint->wMaxPacketSize)
		{
			/* we found a bulk out endpoint */
			if (!dev->write_urb)
			{
				dev->write_urb = usb_alloc_urb(0);
				if (!dev->write_urb) {
					err("No free urbs available");
					goto error;
				}
				dbg("Allocate write URB %p", dev->write_urb);
			}
			buffer_size = endpoint->wMaxPacketSize;
			dev->bulk_out_size = buffer_size;
			dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
			dbg("Allocate %d bytes for OUT endpoint 0x%x", dev->bulk_out_size,
				endpoint->bEndpointAddress);
		}
	}

	if (dev->bulk_in_size)
	{
		dev->bulk_in_buffer = kmalloc (dev->bulk_in_size, GFP_KERNEL);
		if (!dev->bulk_in_buffer) 
		{
			err("Couldn't allocate bulk_in_buffer");
			goto error;
		}
		dbg("Bulk in buffer of %d bytes allocated: %p", 
			dev->bulk_in_size, dev->bulk_in_buffer);
		if (!loadFirmware)
		{
			for (i = 0; i < dev->readBufSize; i++)
			{
				dev->read_buffer[i].buf = kmalloc (dev->bulk_in_size, GFP_KERNEL);
				if (!dev->read_buffer[i].buf) 
				{
					err("Couldn't allocate read_buffer");
					goto error;
				}
				dbg("Bulk in buffer of %d bytes allocated: %p", 
					dev->bulk_in_size, dev->read_buffer[i].buf);
			}
		}
	}

	if (dev->bulk_out_size)
	{
		dev->bulk_out_buffer = kmalloc (dev->bulk_out_size, GFP_KERNEL);
		if (!dev->bulk_out_buffer) 
		{
			err("Couldn't allocate bulk_out_buffer");
			goto error;
		}
		dbg("Bulk out buffer of %d bytes allocated: %p", 
			dev->bulk_out_size, dev->bulk_out_buffer);
	}

	/* initialize the devfs node for this device and register it */
	sprintf(name, "c2420eb%d", dev->minor);
	
	dev->devfs = devfs_register (usb_devfs_handle, name,
				     DEVFS_FL_DEFAULT, USB_MAJOR + 1,
				     USB_C2420EB_MINOR_BASE + dev->minor,
				     S_IFCHR | S_IRUSR | S_IWUSR | 
				     S_IRGRP | S_IWGRP | S_IROTH, 
				     &c2420eb_fops, NULL);

	/* let the user know what node this device is now attached to */
	info ("USB C2420EB device now attached to C2420EB%d", dev->minor);

	info ("Setting configuration");
	if (usb_set_configuration(udev, udev->config[0].bConfigurationValue)) 
	{
		err ("set config failed");
		goto error;
	}
	
	//Load the firmware section
	if (udev->descriptor.idProduct == C2420EB_PRODUCT_ID)
	{
		// Set interface 
 		dbg("Setting interface #0, alt #1");
 		if (usb_set_interface(dev->udev, 0, 1) < 0)
 		{
 			err("Set interface error");
 			goto error;
 		}

		if (c2420eb_initdevice(dev) < 0)
		{
			err ("Device initialization failed");
			goto error;
		}
	}
	//Operational mode
	else
	{
		c2420eb_dev_proc_create(dev);
		if (c2420eb_mkoper(dev) < 0)
			goto error;
	}
	goto exit;

error:
	c2420eb_dev_proc_destroy(dev);
	c2420eb_delete (dev);
	dev = NULL;

exit:
	up (&minor_table_mutex);
	return dev;
}


/**
 *	c2420eb_disconnect
 *
 *	Called by the usb core when the device is removed from the system.
 */
static void c2420eb_disconnect(struct usb_device* udev, void* ptr)
{
	struct c2420eb* dev;
	int minor;

	dev = (struct c2420eb*)ptr;
	
	down (&minor_table_mutex);
	down (&dev->sem);
		
	minor = dev->minor;

	if (udev->descriptor.idProduct == C2420EB_PRODUCT_ID1)
		c2420eb_dev_proc_destroy(dev);

	/* remove our devfs node */
	devfs_unregister(dev->devfs);

	/* if the device is not opened, then we clean up right now 
	*/
	if (!dev->open_count) {
		del_timer(&dev->reset_timer);
		up (&dev->sem);
		c2420eb_delete (dev);
	} else {
		dev->udev = NULL;
		up (&dev->sem);
	}
	info("USB C2420EB #%d now disconnected", minor);
	up (&minor_table_mutex);
}



/**
 *	c2420eb_init
 */
static int __init c2420eb_init(void)
{
	int result;

#ifdef CONFIG_PROC_FS
	result = c2420eb_proc_create();
	if (result < 0) {
		err("Unable to create proc entry. Error number %d", result);
		usb_deregister(&c2420eb_driver);
		return -1;
	}
	
#endif /* CONFIG_PROC_FS */

	/* register this driver with the USB subsystem */
	result = usb_register(&c2420eb_driver);
	if (result < 0) {
		err("usb_register failed for the "__FILE__" driver. Error number %d",
		    result);
		return -1;
	}
	info(DRIVER_DESC " " DRIVER_VERSION);
	return 0;
}


/**
 *	c2420eb_exit
 */
static void __exit c2420eb_exit(void)
{
	/* deregister this driver with the USB subsystem */
	c2420eb_proc_destroy();
	usb_deregister(&c2420eb_driver);
}

module_init (c2420eb_init);
module_exit (c2420eb_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");