[linux-block.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/smp_lock.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>
405f5571	19	#include <linux/smp_lock.h>
1da177e4	20	#include <linux/errno.h>
d5d1ceac	21	#include <linux/mutex.h>
1da177e4 LT	22	#include <asm/uaccess.h>
	23	#include <linux/usb.h>
	24
	25	#define DRIVER_VERSION "USBLCD Driver Version 1.05"
	26
	27	#define USBLCD_MINOR 144
	28
	29	#define IOCTL_GET_HARD_VERSION 1
	30	#define IOCTL_GET_DRV_VERSION 2
	31
	32
	33	static struct usb_device_id id_table [] = {
	34	{ .idVendor = 0x10D2, .match_flags = USB_DEVICE_ID_MATCH_VENDOR, },
	35	{ },
	36	};
	37	MODULE_DEVICE_TABLE (usb, id_table);
	38
d5d1ceac ON	39	static DEFINE_MUTEX(open_disc_mutex);
d5d1ceac ON	40
1da177e4 LT	41
	42	struct usb_lcd {
	43	struct usb_device * udev; /* init: probe_lcd */
	44	struct usb_interface * interface; /* the interface for this device */
	45	unsigned char * bulk_in_buffer; /* the buffer to receive data */
	46	size_t bulk_in_size; /* the size of the receive buffer */
	47	__u8 bulk_in_endpointAddr; /* the address of the bulk in endpoint */
	48	__u8 bulk_out_endpointAddr; /* the address of the bulk out endpoint */
5afeb104 ON	49	struct kref kref;
	50	struct semaphore limit_sem; /* to stop writes at full throttle from
	51	* using up all RAM */
7bbe990c	52	struct usb_anchor submitted; /* URBs to wait for before suspend */
1da177e4 LT	53	};
	54	#define to_lcd_dev(d) container_of(d, struct usb_lcd, kref)
	55
5afeb104 ON	56	#define USB_LCD_CONCURRENT_WRITES 5
5afeb104 ON	57
1da177e4 LT	58	static struct usb_driver lcd_driver;
	59
	60
	61	static void lcd_delete(struct kref *kref)
	62	{
	63	struct usb_lcd *dev = to_lcd_dev(kref);
	64
	65	usb_put_dev(dev->udev);
	66	kfree (dev->bulk_in_buffer);
	67	kfree (dev);
	68	}
	69
	70
	71	static int lcd_open(struct inode inode, struct file file)
	72	{
	73	struct usb_lcd *dev;
	74	struct usb_interface *interface;
7bbe990c	75	int subminor, r;
1da177e4 LT	76
	77	subminor = iminor(inode);
	78
	79	interface = usb_find_interface(&lcd_driver, subminor);
	80	if (!interface) {
	81	err ("USBLCD: %s - error, can't find device for minor %d",
441b62c1	82	__func__, subminor);
d4ead16f	83	return -ENODEV;
1da177e4 LT	84	}
1da177e4 LT	85
d5d1ceac	86	mutex_lock(&open_disc_mutex);
1da177e4	87	dev = usb_get_intfdata(interface);
d5d1ceac ON	88	if (!dev) {
d5d1ceac ON	89	mutex_unlock(&open_disc_mutex);
d4ead16f	90	return -ENODEV;
d5d1ceac	91	}
1da177e4 LT	92
	93	/* increment our usage count for the device */
	94	kref_get(&dev->kref);
d5d1ceac	95	mutex_unlock(&open_disc_mutex);
1da177e4	96
7bbe990c ON	97	/* grab a power reference */
	98	r = usb_autopm_get_interface(interface);
	99	if (r < 0) {
	100	kref_put(&dev->kref, lcd_delete);
	101	return r;
	102	}
	103
1da177e4 LT	104	/* save our object in the file's private structure */
	105	file->private_data = dev;
	106
d4ead16f	107	return 0;
1da177e4 LT	108	}
	109
	110	static int lcd_release(struct inode inode, struct file file)
	111	{
	112	struct usb_lcd *dev;
	113
	114	dev = (struct usb_lcd *)file->private_data;
	115	if (dev == NULL)
	116	return -ENODEV;
	117
	118	/* decrement the count on our device */
7bbe990c	119	usb_autopm_put_interface(dev->interface);
1da177e4 LT	120	kref_put(&dev->kref, lcd_delete);
	121	return 0;
	122	}
	123
	124	static ssize_t lcd_read(struct file file, char __user buffer, size_t count, loff_t *ppos)
	125	{
	126	struct usb_lcd *dev;
	127	int retval = 0;
	128	int bytes_read;
	129
	130	dev = (struct usb_lcd *)file->private_data;
	131
	132	/* do a blocking bulk read to get data from the device */
	133	retval = usb_bulk_msg(dev->udev,
	134	usb_rcvbulkpipe(dev->udev, dev->bulk_in_endpointAddr),
	135	dev->bulk_in_buffer,
	136	min(dev->bulk_in_size, count),
	137	&bytes_read, 10000);
	138
	139	/* if the read was successful, copy the data to userspace */
	140	if (!retval) {
	141	if (copy_to_user(buffer, dev->bulk_in_buffer, bytes_read))
	142	retval = -EFAULT;
	143	else
	144	retval = bytes_read;
	145	}
	146
	147	return retval;
	148	}
	149
5cb4aeca	150	static long lcd_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1da177e4 LT	151	{
	152	struct usb_lcd *dev;
	153	u16 bcdDevice;
	154	char buf[30];
	155
	156	dev = (struct usb_lcd *)file->private_data;
	157	if (dev == NULL)
	158	return -ENODEV;
	159
	160	switch (cmd) {
	161	case IOCTL_GET_HARD_VERSION:
5cb4aeca	162	lock_kernel();
1da177e4 LT	163	bcdDevice = le16_to_cpu((dev->udev)->descriptor.bcdDevice);
	164	sprintf(buf,"%1d%1d.%1d%1d",
	165	(bcdDevice & 0xF000)>>12,
	166	(bcdDevice & 0xF00)>>8,
	167	(bcdDevice & 0xF0)>>4,
	168	(bcdDevice & 0xF));
5cb4aeca	169	unlock_kernel();
1da177e4 LT	170	if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
	171	return -EFAULT;
	172	break;
	173	case IOCTL_GET_DRV_VERSION:
	174	sprintf(buf,DRIVER_VERSION);
	175	if (copy_to_user((void __user *)arg,buf,strlen(buf))!=0)
	176	return -EFAULT;
	177	break;
	178	default:
	179	return -ENOTTY;
	180	break;
	181	}
	182
	183	return 0;
	184	}
	185
7d12e780	186	static void lcd_write_bulk_callback(struct urb *urb)
1da177e4 LT	187	{
1da177e4 LT	188	struct usb_lcd *dev;
0723af13	189	int status = urb->status;
1da177e4	190
cdc97792	191	dev = urb->context;
1da177e4 LT	192
1da177e4 LT	193	/* sync/async unlink faults aren't errors */
0723af13 GKH	194	if (status &&
	195	!(status == -ENOENT \|\|
	196	status == -ECONNRESET \|\|
	197	status == -ESHUTDOWN)) {
1da177e4	198	dbg("USBLCD: %s - nonzero write bulk status received: %d",
441b62c1	199	__func__, status);
1da177e4 LT	200	}
	201
	202	/* free up our allocated buffer */
	203	usb_buffer_free(urb->dev, urb->transfer_buffer_length,
	204	urb->transfer_buffer, urb->transfer_dma);
5afeb104	205	up(&dev->limit_sem);
1da177e4 LT	206	}
	207
	208	static ssize_t lcd_write(struct file file, const char __user user_buffer, size_t count, loff_t *ppos)
	209	{
	210	struct usb_lcd *dev;
5afeb104	211	int retval = 0, r;
1da177e4 LT	212	struct urb *urb = NULL;
	213	char *buf = NULL;
	214
	215	dev = (struct usb_lcd *)file->private_data;
	216
	217	/* verify that we actually have some data to write */
	218	if (count == 0)
	219	goto exit;
	220
5afeb104 ON	221	r = down_interruptible(&dev->limit_sem);
	222	if (r < 0)
	223	return -EINTR;
	224
1da177e4 LT	225	/* create a urb, and a buffer for it, and copy the data to the urb */
1da177e4 LT	226	urb = usb_alloc_urb(0, GFP_KERNEL);
5afeb104 ON	227	if (!urb) {
	228	retval = -ENOMEM;
	229	goto err_no_buf;
	230	}
1da177e4 LT	231
	232	buf = usb_buffer_alloc(dev->udev, count, GFP_KERNEL, &urb->transfer_dma);
	233	if (!buf) {
	234	retval = -ENOMEM;
	235	goto error;
	236	}
	237
	238	if (copy_from_user(buf, user_buffer, count)) {
	239	retval = -EFAULT;
	240	goto error;
	241	}
	242
	243	/* initialize the urb properly */
	244	usb_fill_bulk_urb(urb, dev->udev,
	245	usb_sndbulkpipe(dev->udev, dev->bulk_out_endpointAddr),
	246	buf, count, lcd_write_bulk_callback, dev);
	247	urb->transfer_flags \|= URB_NO_TRANSFER_DMA_MAP;
7bbe990c ON	248
7bbe990c ON	249	usb_anchor_urb(urb, &dev->submitted);
1da177e4 LT	250
	251	/* send the data out the bulk port */
	252	retval = usb_submit_urb(urb, GFP_KERNEL);
	253	if (retval) {
441b62c1	254	err("USBLCD: %s - failed submitting write urb, error %d", __func__, retval);
7bbe990c	255	goto error_unanchor;
1da177e4 LT	256	}
	257
	258	/* release our reference to this urb, the USB core will eventually free it entirely */
	259	usb_free_urb(urb);
	260
	261	exit:
	262	return count;
7bbe990c ON	263	error_unanchor:
7bbe990c ON	264	usb_unanchor_urb(urb);
1da177e4 LT	265	error:
	266	usb_buffer_free(dev->udev, count, buf, urb->transfer_dma);
	267	usb_free_urb(urb);
5afeb104 ON	268	err_no_buf:
5afeb104 ON	269	up(&dev->limit_sem);
1da177e4 LT	270	return retval;
	271	}
	272
066202dd	273	static const struct file_operations lcd_fops = {
1da177e4 LT	274	.owner = THIS_MODULE,
	275	.read = lcd_read,
	276	.write = lcd_write,
	277	.open = lcd_open,
5cb4aeca	278	.unlocked_ioctl = lcd_ioctl,
1da177e4 LT	279	.release = lcd_release,
	280	};
	281
	282	/*
d6e5bcf4 GKH	283	* usb class driver info in order to get a minor number from the usb core,
	284	* and to have the device registered with the driver core
	285	*/
1da177e4	286	static struct usb_class_driver lcd_class = {
d6e5bcf4	287	.name = "lcd%d",
1da177e4	288	.fops = &lcd_fops,
1da177e4 LT	289	.minor_base = USBLCD_MINOR,
	290	};
	291
	292	static int lcd_probe(struct usb_interface interface, const struct usb_device_id id)
	293	{
	294	struct usb_lcd *dev = NULL;
	295	struct usb_host_interface *iface_desc;
	296	struct usb_endpoint_descriptor *endpoint;
	297	size_t buffer_size;
	298	int i;
	299	int retval = -ENOMEM;
	300
	301	/* allocate memory for our device state and initialize it */
80b6ca48	302	dev = kzalloc(sizeof(*dev), GFP_KERNEL);
1da177e4 LT	303	if (dev == NULL) {
	304	err("Out of memory");
	305	goto error;
	306	}
1da177e4	307	kref_init(&dev->kref);
5afeb104	308	sema_init(&dev->limit_sem, USB_LCD_CONCURRENT_WRITES);
7bbe990c	309	init_usb_anchor(&dev->submitted);
1da177e4 LT	310
	311	dev->udev = usb_get_dev(interface_to_usbdev(interface));
	312	dev->interface = interface;
	313
	314	if (le16_to_cpu(dev->udev->descriptor.idProduct) != 0x0001) {
3b6004f3	315	dev_warn(&interface->dev, "USBLCD model not supported.\n");
1da177e4 LT	316	return -ENODEV;
	317	}
	318
	319	/* set up the endpoint information */
	320	/* use only the first bulk-in and bulk-out endpoints */
	321	iface_desc = interface->cur_altsetting;
	322	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
	323	endpoint = &iface_desc->endpoint[i].desc;
	324
	325	if (!dev->bulk_in_endpointAddr &&
b0b660b8	326	usb_endpoint_is_bulk_in(endpoint)) {
1da177e4 LT	327	/* we found a bulk in endpoint */
	328	buffer_size = le16_to_cpu(endpoint->wMaxPacketSize);
	329	dev->bulk_in_size = buffer_size;
	330	dev->bulk_in_endpointAddr = endpoint->bEndpointAddress;
	331	dev->bulk_in_buffer = kmalloc(buffer_size, GFP_KERNEL);
	332	if (!dev->bulk_in_buffer) {
	333	err("Could not allocate bulk_in_buffer");
	334	goto error;
	335	}
	336	}
	337
	338	if (!dev->bulk_out_endpointAddr &&
b0b660b8	339	usb_endpoint_is_bulk_out(endpoint)) {
1da177e4 LT	340	/* we found a bulk out endpoint */
	341	dev->bulk_out_endpointAddr = endpoint->bEndpointAddress;
	342	}
	343	}
	344	if (!(dev->bulk_in_endpointAddr && dev->bulk_out_endpointAddr)) {
	345	err("Could not find both bulk-in and bulk-out endpoints");
	346	goto error;
	347	}
	348
	349	/* save our data pointer in this interface device */
	350	usb_set_intfdata(interface, dev);
	351
	352	/* we can register the device now, as it is ready */
	353	retval = usb_register_dev(interface, &lcd_class);
	354	if (retval) {
	355	/* something prevented us from registering this driver */
	356	err("Not able to get a minor for this device.");
	357	usb_set_intfdata(interface, NULL);
	358	goto error;
	359	}
	360
	361	i = le16_to_cpu(dev->udev->descriptor.bcdDevice);
	362
1b29a375 GKH	363	dev_info(&interface->dev, "USBLCD Version %1d%1d.%1d%1d found "
	364	"at address %d\n", (i & 0xF000)>>12, (i & 0xF00)>>8,
	365	(i & 0xF0)>>4,(i & 0xF), dev->udev->devnum);
1da177e4 LT	366
1da177e4 LT	367	/* let the user know what node this device is now attached to */
1b29a375 GKH	368	dev_info(&interface->dev, "USB LCD device now attached to USBLCD-%d\n",
1b29a375 GKH	369	interface->minor);
1da177e4 LT	370	return 0;
	371
	372	error:
	373	if (dev)
	374	kref_put(&dev->kref, lcd_delete);
	375	return retval;
	376	}
	377
7bbe990c ON	378	static void lcd_draw_down(struct usb_lcd *dev)
	379	{
	380	int time;
	381
	382	time = usb_wait_anchor_empty_timeout(&dev->submitted, 1000);
	383	if (!time)
	384	usb_kill_anchored_urbs(&dev->submitted);
	385	}
	386
	387	static int lcd_suspend(struct usb_interface *intf, pm_message_t message)
	388	{
	389	struct usb_lcd *dev = usb_get_intfdata(intf);
	390
	391	if (!dev)
	392	return 0;
	393	lcd_draw_down(dev);
	394	return 0;
	395	}
	396
	397	static int lcd_resume (struct usb_interface *intf)
	398	{
	399	return 0;
	400	}
	401
1da177e4 LT	402	static void lcd_disconnect(struct usb_interface *interface)
	403	{
	404	struct usb_lcd *dev;
	405	int minor = interface->minor;
	406
d5d1ceac	407	mutex_lock(&open_disc_mutex);
1da177e4 LT	408	dev = usb_get_intfdata(interface);
1da177e4 LT	409	usb_set_intfdata(interface, NULL);
d5d1ceac	410	mutex_unlock(&open_disc_mutex);
1da177e4 LT	411
	412	/* give back our minor */
	413	usb_deregister_dev(interface, &lcd_class);
	414
1da177e4 LT	415	/* decrement our usage count */
	416	kref_put(&dev->kref, lcd_delete);
	417
1b29a375	418	dev_info(&interface->dev, "USB LCD #%d now disconnected\n", minor);
1da177e4 LT	419	}
	420
	421	static struct usb_driver lcd_driver = {
1da177e4 LT	422	.name = "usblcd",
	423	.probe = lcd_probe,
	424	.disconnect = lcd_disconnect,
7bbe990c ON	425	.suspend = lcd_suspend,
7bbe990c ON	426	.resume = lcd_resume,
1da177e4	427	.id_table = id_table,
7bbe990c	428	.supports_autosuspend = 1,
1da177e4 LT	429	};
	430
	431	static int __init usb_lcd_init(void)
	432	{
	433	int result;
	434
	435	result = usb_register(&lcd_driver);
	436	if (result)
	437	err("usb_register failed. Error number %d", result);
	438
	439	return result;
	440	}
	441
	442
	443	static void __exit usb_lcd_exit(void)
	444	{
	445	usb_deregister(&lcd_driver);
	446	}
	447
	448	module_init(usb_lcd_init);
	449	module_exit(usb_lcd_exit);
	450
	451	MODULE_AUTHOR("Georges Toth <g.toth@e-biz.lu>");
	452	MODULE_DESCRIPTION(DRIVER_VERSION);
	453	MODULE_LICENSE("GPL");