[deliverable/linux.git] / drivers / usb / misc / usblcd.c

/*****************************************************************************
 *                          USBLCD Kernel Driver                             *
 *                            Version 1.05                                   *
 *             (C) 2005 Georges Toth <g.toth@e-biz.lu>                       *
 *                                                                           *
 *     This file is licensed under the GPL. See COPYING in the package.      *
 * Based on usb-skeleton.c 2.0 by Greg Kroah-Hartman (greg@kroah.com)        *
 *                                                                           *
 *                                                                           *
 * 28.02.05 Complete rewrite of the original usblcd.c driver,                *
 *          based on usb_skeleton.c.                                         *
 *          This new driver allows more than one USB-LCD to be connected     *
 *          and controlled, at once                                          *
 *****************************************************************************/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/mutex.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, },
	{ },
};
MODULE_DEVICE_TABLE (usb, id_table);

static DEFINE_MUTEX(open_disc_mutex);


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 */
	struct usb_anchor	submitted;		/* URBs to wait for before suspend */
};
#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)

#define USB_LCD_CONCURRENT_WRITES	5

static struct usb_driver lcd_driver;


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, r;

	subminor = iminor(inode);

	interface = usb_find_interface(&lcd_driver, subminor);
	if (!interface) {
		err ("USBLCD: %s - error, can't find device for minor %d",
		     __func__, subminor);
		return -ENODEV;
	}

	mutex_lock(&open_disc_mutex);
	dev = usb_get_intfdata(interface);
	if (!dev) {
		mutex_unlock(&open_disc_mutex);
		return -ENODEV;
	}

	/* increment our usage count for the device */
	kref_get(&dev->kref);
	mutex_unlock(&open_disc_mutex);

	/* grab a power reference */
	r = usb_autopm_get_interface(interface);
	if (r < 0) {
		kref_put(&dev->kref, lcd_delete);
		return r;
	}

	/* save our object in the file's private structure */
	file->private_data = dev;

	return 0;
}

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 */
	usb_autopm_put_interface(dev->interface);
	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, 10000);

	/* 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 long lcd_ioctl(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:
		lock_kernel();
		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));
		unlock_kernel();
		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;
	int status = urb->status;

	dev = urb->context;

	/* sync/async unlink faults aren't errors */
	if (status &&
	    !(status == -ENOENT ||
	      status == -ECONNRESET ||
              status == -ESHUTDOWN)) {
		dbg("USBLCD: %s - nonzero write bulk status received: %d",
		    __func__, 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;

	usb_anchor_urb(urb, &dev->submitted);
	
	/* 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", __func__, retval);
		goto error_unanchor;
	}
	
	/* release our reference to this urb, the USB core will eventually free it entirely */
	usb_free_urb(urb);

exit:
	return count;
error_unanchor:
	usb_unanchor_urb(urb);
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,
	.unlocked_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 =         "lcd%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);
	init_usb_anchor(&dev->submitted);

	dev->udev = usb_get_dev(interface_to_usbdev(interface));
	dev->interface = interface;

	if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
		dev_warn(&interface->dev, "USBLCD model not supported.\n");
		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);

	dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
		 "at address %d\n", (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 */
	dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
		 interface->minor);
	return 0;

error:
	if (dev)
		kref_put(&dev->kref, lcd_delete);
	return retval;
}

static void lcd_draw_down(struct usb_lcd *dev)
{
	int time;

	time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
	if (!time)
		usb_kill_anchored_urbs(&dev->submitted);
}

static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
{
	struct usb_lcd *dev = usb_get_intfdata(intf);

	if (!dev)
		return 0;
	lcd_draw_down(dev);
	return 0;
}

static int lcd_resume (struct usb_interface *intf)
{
	return 0;
}

static void lcd_disconnect(struct usb_interface *interface)
{
	struct usb_lcd *dev;
        int minor = interface->minor;

	mutex_lock(&open_disc_mutex);
        dev = usb_get_intfdata(interface);
        usb_set_intfdata(interface, NULL);
	mutex_unlock(&open_disc_mutex);

        /* give back our minor */
        usb_deregister_dev(interface, &lcd_class);
 
	/* decrement our usage count */
	kref_put(&dev->kref, lcd_delete);

	dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
}

static struct usb_driver lcd_driver = {
	.name =		"usblcd",
	.probe =	lcd_probe,
	.disconnect =	lcd_disconnect,
	.suspend =	lcd_suspend,
	.resume =	lcd_resume,
	.id_table =	id_table,
	.supports_autosuspend = 1,
};

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 <g.toth@e-biz.lu>");
MODULE_DESCRIPTION(DRIVER_VERSION);
MODULE_LICENSE("GPL");
Commit	Line	Data
1da177e4 LT	1	/*****************************************************************************
	2	* USBLCD Kernel Driver *
	3	* Version 1.05 *
	4	* (C) 2005 Georges Toth <g.toth@e-biz.lu> *
	5	* *
	6	* This file is licensed under the GPL. See COPYING in the package. *
	7	* Based on usb-skeleton.c 2.0 by Greg Kroah-Hartman (greg@kroah.com) *
	8	* *
	9	* *
	10	* 28.02.05 Complete rewrite of the original usblcd.c driver, *
	11	* based on usb_skeleton.c. *
	12	* This new driver allows more than one USB-LCD to be connected *
	13	* and controlled, at once *
	14	*****************************************************************************/
	15	#include <linux/module.h>
	16	#include <linux/kernel.h>
	17	#include <linux/init.h>
	18	#include <linux/slab.h>
	19	#include <linux/errno.h>
d5d1ceac	20	#include <linux/mutex.h>
1da177e4 LT	21	#include <asm/uaccess.h>
	22	#include <linux/usb.h>
	23
	24	#define DRIVER_VERSION "USBLCD Driver Version 1.05"
	25
	26	#define USBLCD_MINOR 144
	27
	28	#define IOCTL_GET_HARD_VERSION 1
	29	#define IOCTL_GET_DRV_VERSION 2
	30
	31
	32	static struct usb_device_id id_table [] = {
	33	{ .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
	34	{ },
	35	};
	36	MODULE_DEVICE_TABLE (usb, id_table);
	37
d5d1ceac ON	38	static DEFINE_MUTEX(open_disc_mutex);
d5d1ceac ON	39
1da177e4 LT	40
	41	struct usb_lcd {
	42	struct usb_device * udev; /* init: probe_lcd */
	43	struct usb_interface * interface; /* the interface for this device */
	44	unsigned char * bulk_in_buffer; /* the buffer to receive data */
	45	size_t bulk_in_size; /* the size of the receive buffer */
	46	__u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
	47	__u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */
5afeb104 ON	48	struct kref kref;
	49	struct semaphore limit_sem; /* to stop writes at full throttle from
	50	* using up all RAM */
7bbe990c	51	struct usb_anchor submitted; /* URBs to wait for before suspend */
1da177e4 LT	52	};
	53	#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
	54
5afeb104 ON	55	#define USB_LCD_CONCURRENT_WRITES 5
5afeb104 ON	56
1da177e4 LT	57	static struct usb_driver lcd_driver;
	58
	59
	60	static void lcd_delete(struct kref *kref)
	61	{
	62	struct usb_lcd *dev = to_lcd_dev(kref);
	63
	64	usb_put_dev(dev->udev);
	65	kfree (dev->bulk_in_buffer);
	66	kfree (dev);
	67	}
	68
	69
	70	static int lcd_open(struct inode inode, struct file file)
	71	{
	72	struct usb_lcd *dev;
	73	struct usb_interface *interface;
7bbe990c	74	int subminor, r;
1da177e4 LT	75
	76	subminor = iminor(inode);
	77
	78	interface = usb_find_interface(&lcd_driver, subminor);
	79	if (!interface) {
	80	err ("USBLCD: %s - error, can't find device for minor %d",
441b62c1	81	__func__, subminor);
d4ead16f	82	return -ENODEV;
1da177e4 LT	83	}
1da177e4 LT	84
d5d1ceac	85	mutex_lock(&open_disc_mutex);
1da177e4	86	dev = usb_get_intfdata(interface);
d5d1ceac ON	87	if (!dev) {
d5d1ceac ON	88	mutex_unlock(&open_disc_mutex);
d4ead16f	89	return -ENODEV;
d5d1ceac	90	}
1da177e4 LT	91
	92	/* increment our usage count for the device */
	93	kref_get(&dev->kref);
d5d1ceac	94	mutex_unlock(&open_disc_mutex);
1da177e4	95
7bbe990c ON	96	/* grab a power reference */
	97	r = usb_autopm_get_interface(interface);
	98	if (r < 0) {
	99	kref_put(&dev->kref, lcd_delete);
	100	return r;
	101	}
	102
1da177e4 LT	103	/* save our object in the file's private structure */
	104	file->private_data = dev;
	105
d4ead16f	106	return 0;
1da177e4 LT	107	}
	108
	109	static int lcd_release(struct inode inode, struct file file)
	110	{
	111	struct usb_lcd *dev;
	112
	113	dev = (struct usb_lcd *)file->private_data;
	114	if (dev == NULL)
	115	return -ENODEV;
	116
	117	/* decrement the count on our device */
7bbe990c	118	usb_autopm_put_interface(dev->interface);
1da177e4 LT	119	kref_put(&dev->kref, lcd_delete);
	120	return 0;
	121	}
	122
	123	static ssize_t lcd_read(struct file file, char __user buffer, size_t count, loff_t *ppos)
	124	{
	125	struct usb_lcd *dev;
	126	int retval = 0;
	127	int bytes_read;
	128
	129	dev = (struct usb_lcd *)file->private_data;
	130
	131	/* do a blocking bulk read to get data from the device */
	132	retval = usb_bulk_msg(dev->udev,
	133	usb_rcvbulkpipe(dev->udev, dev->bulk_in_endpointAddr),
	134	dev->bulk_in_buffer,
	135	min(dev->bulk_in_size, count),
	136	&bytes_read, 10000);
	137
	138	/* if the read was successful, copy the data to userspace */
	139	if (!retval) {
	140	if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
	141	retval = -EFAULT;
	142	else
	143	retval = bytes_read;
	144	}
	145
	146	return retval;
	147	}
	148
5cb4aeca	149	static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1da177e4 LT	150	{
	151	struct usb_lcd *dev;
	152	u16 bcdDevice;
	153	char buf[30];
	154
	155	dev = (struct usb_lcd *)file->private_data;
	156	if (dev == NULL)
	157	return -ENODEV;
	158
	159	switch (cmd) {
	160	case IOCTL_GET_HARD_VERSION:
5cb4aeca	161	lock_kernel();
1da177e4 LT	162	bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
	163	sprintf(buf,"%1d%1d.%1d%1d",
	164	(bcdDevice & 0xF000)>>12,
	165	(bcdDevice & 0xF00)>>8,
	166	(bcdDevice & 0xF0)>>4,
	167	(bcdDevice & 0xF));
5cb4aeca	168	unlock_kernel();
1da177e4 LT	169	if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
	170	return -EFAULT;
	171	break;
	172	case IOCTL_GET_DRV_VERSION:
	173	sprintf(buf,DRIVER_VERSION);
	174	if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
	175	return -EFAULT;
	176	break;
	177	default:
	178	return -ENOTTY;
	179	break;
	180	}
	181
	182	return 0;
	183	}
	184
7d12e780	185	static void lcd_write_bulk_callback(struct urb *urb)
1da177e4 LT	186	{
1da177e4 LT	187	struct usb_lcd *dev;
0723af13	188	int status = urb->status;
1da177e4	189
cdc97792	190	dev = urb->context;
1da177e4 LT	191
1da177e4 LT	192	/* sync/async unlink faults aren't errors */
0723af13 GKH	193	if (status &&
	194	!(status == -ENOENT \|\|
	195	status == -ECONNRESET \|\|
	196	status == -ESHUTDOWN)) {
1da177e4	197	dbg("USBLCD: %s - nonzero write bulk status received: %d",
441b62c1	198	__func__, status);
1da177e4 LT	199	}
	200
	201	/* free up our allocated buffer */
	202	usb_buffer_free(urb->dev, urb->transfer_buffer_length,
	203	urb->transfer_buffer, urb->transfer_dma);
5afeb104	204	up(&dev->limit_sem);
1da177e4 LT	205	}
	206
	207	static ssize_t lcd_write(struct file file, const char __user user_buffer, size_t count, loff_t *ppos)
	208	{
	209	struct usb_lcd *dev;
5afeb104	210	int retval = 0, r;
1da177e4 LT	211	struct urb *urb = NULL;
	212	char *buf = NULL;
	213
	214	dev = (struct usb_lcd *)file->private_data;
	215
	216	/* verify that we actually have some data to write */
	217	if (count == 0)
	218	goto exit;
	219
5afeb104 ON	220	r = down_interruptible(&dev->limit_sem);
	221	if (r < 0)
	222	return -EINTR;
	223
1da177e4 LT	224	/* create a urb, and a buffer for it, and copy the data to the urb */
1da177e4 LT	225	urb = usb_alloc_urb(0, GFP_KERNEL);
5afeb104 ON	226	if (!urb) {
	227	retval = -ENOMEM;
	228	goto err_no_buf;
	229	}
1da177e4 LT	230
	231	buf = usb_buffer_alloc(dev->udev, count, GFP_KERNEL, &urb->transfer_dma);
	232	if (!buf) {
	233	retval = -ENOMEM;
	234	goto error;
	235	}
	236
	237	if (copy_from_user(buf, user_buffer, count)) {
	238	retval = -EFAULT;
	239	goto error;
	240	}
	241
	242	/* initialize the urb properly */
	243	usb_fill_bulk_urb(urb, dev->udev,
	244	usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
	245	buf, count, lcd_write_bulk_callback, dev);
	246	urb->transfer_flags \|= URB_NO_TRANSFER_DMA_MAP;
7bbe990c ON	247
7bbe990c ON	248	usb_anchor_urb(urb, &dev->submitted);
1da177e4 LT	249
	250	/* send the data out the bulk port */
	251	retval = usb_submit_urb(urb, GFP_KERNEL);
	252	if (retval) {
441b62c1	253	err("USBLCD: %s - failed submitting write urb, error %d", __func__, retval);
7bbe990c	254	goto error_unanchor;
1da177e4 LT	255	}
	256
	257	/* release our reference to this urb, the USB core will eventually free it entirely */
	258	usb_free_urb(urb);
	259
	260	exit:
	261	return count;
7bbe990c ON	262	error_unanchor:
7bbe990c ON	263	usb_unanchor_urb(urb);
1da177e4 LT	264	error:
	265	usb_buffer_free(dev->udev, count, buf, urb->transfer_dma);
	266	usb_free_urb(urb);
5afeb104 ON	267	err_no_buf:
5afeb104 ON	268	up(&dev->limit_sem);
1da177e4 LT	269	return retval;
	270	}
	271
066202dd	272	static const struct file_operations lcd_fops = {
1da177e4 LT	273	.owner = THIS_MODULE,
	274	.read = lcd_read,
	275	.write = lcd_write,
	276	.open = lcd_open,
5cb4aeca	277	.unlocked_ioctl = lcd_ioctl,
1da177e4 LT	278	.release = lcd_release,
	279	};
	280
	281	/*
d6e5bcf4 GKH	282	* usb class driver info in order to get a minor number from the usb core,
	283	* and to have the device registered with the driver core
	284	*/
1da177e4	285	static struct usb_class_driver lcd_class = {
d6e5bcf4	286	.name = "lcd%d",
1da177e4	287	.fops = &lcd_fops,
1da177e4 LT	288	.minor_base = USBLCD_MINOR,
	289	};
	290
	291	static int lcd_probe(struct usb_interface interface, const struct usb_device_id id)
	292	{
	293	struct usb_lcd *dev = NULL;
	294	struct usb_host_interface *iface_desc;
	295	struct usb_endpoint_descriptor *endpoint;
	296	size_t buffer_size;
	297	int i;
	298	int retval = -ENOMEM;
	299
	300	/* allocate memory for our device state and initialize it */
80b6ca48	301	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1da177e4 LT	302	if (dev == NULL) {
	303	err("Out of memory");
	304	goto error;
	305	}
1da177e4	306	kref_init(&dev->kref);
5afeb104	307	sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
7bbe990c	308	init_usb_anchor(&dev->submitted);
1da177e4 LT	309
	310	dev->udev = usb_get_dev(interface_to_usbdev(interface));
	311	dev->interface = interface;
	312
	313	if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
3b6004f3	314	dev_warn(&interface->dev, "USBLCD model not supported.\n");
1da177e4 LT	315	return -ENODEV;
	316	}
	317
	318	/* set up the endpoint information */
	319	/* use only the first bulk-in and bulk-out endpoints */
	320	iface_desc = interface->cur_altsetting;
	321	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
	322	endpoint = &iface_desc->endpoint[i].desc;
	323
	324	if (!dev->bulk_in_endpointAddr &&
b0b660b8	325	usb_endpoint_is_bulk_in(endpoint)) {
1da177e4 LT	326	/* we found a bulk in endpoint */
	327	buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
	328	dev->bulk_in_size = buffer_size;
	329	dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
	330	dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
	331	if (!dev->bulk_in_buffer) {
	332	err("Could not allocate bulk_in_buffer");
	333	goto error;
	334	}
	335	}
	336
	337	if (!dev->bulk_out_endpointAddr &&
b0b660b8	338	usb_endpoint_is_bulk_out(endpoint)) {
1da177e4 LT	339	/* we found a bulk out endpoint */
	340	dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
	341	}
	342	}
	343	if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
	344	err("Could not find both bulk-in and bulk-out endpoints");
	345	goto error;
	346	}
	347
	348	/* save our data pointer in this interface device */
	349	usb_set_intfdata(interface, dev);
	350
	351	/* we can register the device now, as it is ready */
	352	retval = usb_register_dev(interface, &lcd_class);
	353	if (retval) {
	354	/* something prevented us from registering this driver */
	355	err("Not able to get a minor for this device.");
	356	usb_set_intfdata(interface, NULL);
	357	goto error;
	358	}
	359
	360	i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
	361
1b29a375 GKH	362	dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
	363	"at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8,
	364	(i & 0xF0)>>4,(i & 0xF), dev->udev->devnum);
1da177e4 LT	365
1da177e4 LT	366	/* let the user know what node this device is now attached to */
1b29a375 GKH	367	dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
1b29a375 GKH	368	interface->minor);
1da177e4 LT	369	return 0;
	370
	371	error:
	372	if (dev)
	373	kref_put(&dev->kref, lcd_delete);
	374	return retval;
	375	}
	376
7bbe990c ON	377	static void lcd_draw_down(struct usb_lcd *dev)
	378	{
	379	int time;
	380
	381	time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
	382	if (!time)
	383	usb_kill_anchored_urbs(&dev->submitted);
	384	}
	385
	386	static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
	387	{
	388	struct usb_lcd *dev = usb_get_intfdata(intf);
	389
	390	if (!dev)
	391	return 0;
	392	lcd_draw_down(dev);
	393	return 0;
	394	}
	395
	396	static int lcd_resume (struct usb_interface *intf)
	397	{
	398	return 0;
	399	}
	400
1da177e4 LT	401	static void lcd_disconnect(struct usb_interface *interface)
	402	{
	403	struct usb_lcd *dev;
	404	int minor = interface->minor;
	405
d5d1ceac	406	mutex_lock(&open_disc_mutex);
1da177e4 LT	407	dev = usb_get_intfdata(interface);
1da177e4 LT	408	usb_set_intfdata(interface, NULL);
d5d1ceac	409	mutex_unlock(&open_disc_mutex);
1da177e4 LT	410
	411	/* give back our minor */
	412	usb_deregister_dev(interface, &lcd_class);
	413
1da177e4 LT	414	/* decrement our usage count */
	415	kref_put(&dev->kref, lcd_delete);
	416
1b29a375	417	dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
1da177e4 LT	418	}
	419
	420	static struct usb_driver lcd_driver = {
1da177e4 LT	421	.name = "usblcd",
	422	.probe = lcd_probe,
	423	.disconnect = lcd_disconnect,
7bbe990c ON	424	.suspend = lcd_suspend,
7bbe990c ON	425	.resume = lcd_resume,
1da177e4	426	.id_table = id_table,
7bbe990c	427	.supports_autosuspend = 1,
1da177e4 LT	428	};
	429
	430	static int __init usb_lcd_init(void)
	431	{
	432	int result;
	433
	434	result = usb_register(&lcd_driver);
	435	if (result)
	436	err("usb_register failed. Error number %d", result);
	437
	438	return result;
	439	}
	440
	441
	442	static void __exit usb_lcd_exit(void)
	443	{
	444	usb_deregister(&lcd_driver);
	445	}
	446
	447	module_init(usb_lcd_init);
	448	module_exit(usb_lcd_exit);
	449
	450	MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>");
	451	MODULE_DESCRIPTION(DRIVER_VERSION);
	452	MODULE_LICENSE("GPL");