pcwd_usb.c

linux-2.6.15.6

				retval = 0;
			}

			if (new_options & WDIOS_ENABLECARD) {
				usb_pcwd_start(usb_pcwd_device);
				retval = 0;
			}

			return retval;
		}

		case WDIOC_SETTIMEOUT:
		{
			int new_heartbeat;

			if (get_user(new_heartbeat, p))
				return -EFAULT;

			if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
			    return -EINVAL;

			usb_pcwd_keepalive(usb_pcwd_device);
			/* Fall */
		}

		case WDIOC_GETTIMEOUT:
			return put_user(heartbeat, p);

		default:
			return -ENOIOCTLCMD;
	}
}

static int usb_pcwd_open(struct inode *inode, struct file *file)
{
	/* /dev/watchdog can only be opened once */
	if (test_and_set_bit(0, &is_active))
		return -EBUSY;

	/* Activate */
	usb_pcwd_start(usb_pcwd_device);
	usb_pcwd_keepalive(usb_pcwd_device);
	return nonseekable_open(inode, file);
}

static int usb_pcwd_release(struct inode *inode, struct file *file)
{
	/*
	 *      Shut off the timer.
	 */
	if (expect_release == 42) {
		usb_pcwd_stop(usb_pcwd_device);
	} else {
		printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
		usb_pcwd_keepalive(usb_pcwd_device);
	}
	expect_release = 0;
	clear_bit(0, &is_active);
	return 0;
}

/*
 *	/dev/temperature handling
 */

static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
				size_t len, loff_t *ppos)
{
	int temperature;

	if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
		return -EFAULT;

	if (copy_to_user(data, &temperature, 1))
		return -EFAULT;

	return 1;
}

static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
{
	return nonseekable_open(inode, file);
}

static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
{
	return 0;
}

/*
 *	Notify system
 */

static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
{
	if (code==SYS_DOWN || code==SYS_HALT) {
		/* Turn the WDT off */
		usb_pcwd_stop(usb_pcwd_device);
	}

	return NOTIFY_DONE;
}

/*
 *	Kernel Interfaces
 */

static struct file_operations usb_pcwd_fops = {
	.owner =	THIS_MODULE,
	.llseek =	no_llseek,
	.write =	usb_pcwd_write,
	.ioctl =	usb_pcwd_ioctl,
	.open =		usb_pcwd_open,
	.release =	usb_pcwd_release,
};

static struct miscdevice usb_pcwd_miscdev = {
	.minor =	WATCHDOG_MINOR,
	.name =		"watchdog",
	.fops =		&usb_pcwd_fops,
};

static struct file_operations usb_pcwd_temperature_fops = {
	.owner =	THIS_MODULE,
	.llseek =	no_llseek,
	.read =		usb_pcwd_temperature_read,
	.open =		usb_pcwd_temperature_open,
	.release =	usb_pcwd_temperature_release,
};

static struct miscdevice usb_pcwd_temperature_miscdev = {
	.minor =	TEMP_MINOR,
	.name =		"temperature",
	.fops =		&usb_pcwd_temperature_fops,
};

static struct notifier_block usb_pcwd_notifier = {
	.notifier_call =	usb_pcwd_notify_sys,
};

/**
 *	usb_pcwd_delete
 */
static inline void usb_pcwd_delete (struct usb_pcwd_private *usb_pcwd)
{
	if (usb_pcwd->intr_urb != NULL)
		usb_free_urb (usb_pcwd->intr_urb);
	if (usb_pcwd->intr_buffer != NULL)
		usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
				usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
	kfree (usb_pcwd);
}

/**
 *	usb_pcwd_probe
 *
 *	Called by the usb core when a new device is connected that it thinks
 *	this driver might be interested in.
 */
static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
{
	struct usb_device *udev = interface_to_usbdev(interface);
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	struct usb_pcwd_private *usb_pcwd = NULL;
	int pipe, maxp;
	int retval = -ENOMEM;
	int got_fw_rev;
	unsigned char fw_rev_major, fw_rev_minor;
	char fw_ver_str[20];
	unsigned char option_switches, dummy;

	cards_found++;
	if (cards_found > 1) {
		printk(KERN_ERR PFX "This driver only supports 1 device\n");
		return -ENODEV;
	}

	/* get the active interface descriptor */
	iface_desc = interface->cur_altsetting;

	/* check out that we have a HID device */
	if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
		printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
		return -ENODEV;
	}

	/* check out the endpoint: it has to be Interrupt & IN */
	endpoint = &iface_desc->endpoint[0].desc;

	if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
	     ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
				== USB_ENDPOINT_XFER_INT))) {
		/* we didn't find a Interrupt endpoint with direction IN */
		printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
		return -ENODEV;
	}

	/* get a handle to the interrupt data pipe */
	pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
	maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));

	/* allocate memory for our device and initialize it */
	usb_pcwd = kmalloc (sizeof(struct usb_pcwd_private), GFP_KERNEL);
	if (usb_pcwd == NULL) {
		printk(KERN_ERR PFX "Out of memory\n");
		goto error;
	}
	memset (usb_pcwd, 0x00, sizeof (*usb_pcwd));

	usb_pcwd_device = usb_pcwd;

	init_MUTEX (&usb_pcwd->sem);
	usb_pcwd->udev = udev;
	usb_pcwd->interface = interface;
	usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
	usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? le16_to_cpu(endpoint->wMaxPacketSize) : 8);

	/* set up the memory buffer's */
	if (!(usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, SLAB_ATOMIC, &usb_pcwd->intr_dma))) {
		printk(KERN_ERR PFX "Out of memory\n");
		goto error;
	}

	/* allocate the urb's */
	usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
	if (!usb_pcwd->intr_urb) {
		printk(KERN_ERR PFX "Out of memory\n");
		goto error;
	}

	/* initialise the intr urb's */
	usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
			usb_pcwd->intr_buffer, usb_pcwd->intr_size,
			usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
	usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
	usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;

	/* register our interrupt URB with the USB system */
	if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
		printk(KERN_ERR PFX "Problem registering interrupt URB\n");
		retval = -EIO; /* failure */
		goto error;
	}

	/* The device exists and can be communicated with */
	usb_pcwd->exists = 1;

	/* disable card */
	usb_pcwd_stop(usb_pcwd);

	/* Get the Firmware Version */
	got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
	if (got_fw_rev) {
		sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
	} else {
		sprintf(fw_ver_str, "<card no answer>");
	}

	printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
		fw_ver_str);

	/* Get switch settings */
	usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);

	printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
		option_switches,
		((option_switches & 0x10) ? "ON" : "OFF"),
		((option_switches & 0x08) ? "ON" : "OFF"));

	/* Check that the heartbeat value is within it's range ; if not reset to the default */
	if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
		usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
		printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
			WATCHDOG_HEARTBEAT);
	}

	retval = register_reboot_notifier(&usb_pcwd_notifier);
	if (retval != 0) {
		printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
			retval);
		goto error;
	}

	retval = misc_register(&usb_pcwd_temperature_miscdev);
	if (retval != 0) {
		printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			TEMP_MINOR, retval);
		goto err_out_unregister_reboot;
	}

	retval = misc_register(&usb_pcwd_miscdev);
	if (retval != 0) {
		printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
			WATCHDOG_MINOR, retval);
		goto err_out_misc_deregister;
	}

	/* we can register the device now, as it is ready */
	usb_set_intfdata (interface, usb_pcwd);

	printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
		heartbeat, nowayout);

	return 0;

err_out_misc_deregister:
	misc_deregister(&usb_pcwd_temperature_miscdev);
err_out_unregister_reboot:
	unregister_reboot_notifier(&usb_pcwd_notifier);
error:
	usb_pcwd_delete (usb_pcwd);
	usb_pcwd_device = NULL;
	return retval;
}


/**
 *	usb_pcwd_disconnect
 *
 *	Called by the usb core when the device is removed from the system.
 *
 *	This routine guarantees that the driver will not submit any more urbs
 *	by clearing dev->udev.
 */
static void usb_pcwd_disconnect(struct usb_interface *interface)
{
	struct usb_pcwd_private *usb_pcwd;

	/* prevent races with open() */
	down (&disconnect_sem);

	usb_pcwd = usb_get_intfdata (interface);
	usb_set_intfdata (interface, NULL);

	down (&usb_pcwd->sem);

	/* Stop the timer before we leave */
	if (!nowayout)
		usb_pcwd_stop(usb_pcwd);

	/* We should now stop communicating with the USB PCWD device */
	usb_pcwd->exists = 0;

	/* Deregister */
	misc_deregister(&usb_pcwd_miscdev);
	misc_deregister(&usb_pcwd_temperature_miscdev);
	unregister_reboot_notifier(&usb_pcwd_notifier);

	up (&usb_pcwd->sem);

	/* Delete the USB PCWD device */
	usb_pcwd_delete(usb_pcwd);

	cards_found--;

	up (&disconnect_sem);

	printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
}



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

	/* register this driver with the USB subsystem */
	result = usb_register(&usb_pcwd_driver);
	if (result) {
		printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
		    result);
		return result;
	}

	printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION " (" DRIVER_DATE ")\n");
	return 0;
}


/**
 *	usb_pcwd_exit
 */
static void __exit usb_pcwd_exit(void)
{
	/* deregister this driver with the USB subsystem */
	usb_deregister(&usb_pcwd_driver);
}


module_init (usb_pcwd_init);
module_exit (usb_pcwd_exit);