drivers/usb/misc/usbsevseg.c - third_party/linux - Git at Google

 /*
  * USB 7 Segment Driver
  *
  * Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
  * Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
  *
  *	This program is free software; you can redistribute it and/or
  *	modify it under the terms of the GNU General Public License as
  *	published by the Free Software Foundation, version 2.
  *
  */

 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/usb.h>


 #define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
 #define DRIVER_DESC "USB 7 Segment Driver"

 #define VENDOR_ID	0x0fc5
 #define PRODUCT_ID	0x1227
 #define MAXLEN		6

 /* table of devices that work with this driver */
 static struct usb_device_id id_table[] = {
 	{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
 	{ },
 };
 MODULE_DEVICE_TABLE(usb, id_table);

 /* the different text display modes the device is capable of */
 static char *display_textmodes[] = {"raw", "hex", "ascii", NULL};

 struct usb_sevsegdev {
 	struct usb_device *udev;
 	struct usb_interface *intf;

 	u8 powered;
 	u8 mode_msb;
 	u8 mode_lsb;
 	u8 decimals[MAXLEN];
 	u8 textmode;
 	u8 text[MAXLEN];
 	u16 textlength;

 	u8 shadow_power; /* for PM */
 };

 /* sysfs_streq can't replace this completely
  * If the device was in hex mode, and the user wanted a 0,
  * if str commands are used, we would assume the end of string
  * so mem commands are used.
  */
 inline size_t my_memlen(const char *buf, size_t count)
 {
 	if (count > 0 && buf[count-1] == '\n')
 		return count - 1;
 	else
 		return count;
 }

 static void update_display_powered(struct usb_sevsegdev *mydev)
 {
 	int rc;

 	if (!mydev->shadow_power && mydev->powered) {
 		rc = usb_autopm_get_interface(mydev->intf);
 		if (rc < 0)
 			return;
 	}

 	rc = usb_control_msg(mydev->udev,
 			usb_sndctrlpipe(mydev->udev, 0),
 			0x12,
 			0x48,
 			(80 * 0x100) + 10, /*  (power mode) */
 			(0x00 * 0x100) + (mydev->powered ? 1 : 0),
 			NULL,
 			0,
 			2000);
 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);

 	if (mydev->shadow_power && !mydev->powered)
 		usb_autopm_put_interface(mydev->intf);
 }

 static void update_display_mode(struct usb_sevsegdev *mydev)
 {
 	int rc;

 	if(mydev->shadow_power != 1)
 		return;

 	rc = usb_control_msg(mydev->udev,
 			usb_sndctrlpipe(mydev->udev, 0),
 			0x12,
 			0x48,
 			(82 * 0x100) + 10, /* (set mode) */
 			(mydev->mode_msb * 0x100) + mydev->mode_lsb,
 			NULL,
 			0,
 			2000);

 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
 }

 static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
 {
 	int rc;
 	int i;
 	unsigned char *buffer;
 	u8 decimals = 0;

 	if(mydev->shadow_power != 1)
 		return;

 	buffer = kzalloc(MAXLEN, mf);
 	if (!buffer) {
 		dev_err(&mydev->udev->dev, "out of memory\n");
 		return;
 	}

 	/* The device is right to left, where as you write left to right */
 	for (i = 0; i < mydev->textlength; i++)
 		buffer[i] = mydev->text[mydev->textlength-1-i];

 	rc = usb_control_msg(mydev->udev,
 			usb_sndctrlpipe(mydev->udev, 0),
 			0x12,
 			0x48,
 			(85 * 0x100) + 10, /* (write text) */
 			(0 * 0x100) + mydev->textmode, /* mode  */
 			buffer,
 			mydev->textlength,
 			2000);

 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);

 	kfree(buffer);

 	/* The device is right to left, where as you write left to right */
 	for (i = 0; i < sizeof(mydev->decimals); i++)
 		decimals |= mydev->decimals[i] << i;

 	rc = usb_control_msg(mydev->udev,
 			usb_sndctrlpipe(mydev->udev, 0),
 			0x12,
 			0x48,
 			(86 * 0x100) + 10, /* (set decimal) */
 			(0 * 0x100) + decimals, /* decimals */
 			NULL,
 			0,
 			2000);

 	if (rc < 0)
 		dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
 }

 #define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn)		\
 static ssize_t show_attr_##name(struct device *dev, 		\
 	struct device_attribute *attr, char *buf) 		\
 {								\
 	struct usb_interface *intf = to_usb_interface(dev);	\
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);	\
 								\
 	return sprintf(buf, "%u\n", mydev->name);		\
 }								\
 								\
 static ssize_t set_attr_##name(struct device *dev, 		\
 	struct device_attribute *attr, const char *buf, size_t count) \
 {								\
 	struct usb_interface *intf = to_usb_interface(dev);	\
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);	\
 								\
 	mydev->name = simple_strtoul(buf, NULL, 10);		\
 	update_fcn(mydev); 					\
 								\
 	return count;						\
 }								\
 static DEVICE_ATTR(name, S_IWUGO | S_IRUGO, show_attr_##name, set_attr_##name);

 static ssize_t show_attr_text(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);

 	return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
 }

 static ssize_t set_attr_text(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 	size_t end = my_memlen(buf, count);

 	if (end > sizeof(mydev->text))
 		return -EINVAL;

 	memset(mydev->text, 0, sizeof(mydev->text));
 	mydev->textlength = end;

 	if (end > 0)
 		memcpy(mydev->text, buf, end);

 	update_display_visual(mydev, GFP_KERNEL);
 	return count;
 }

 static DEVICE_ATTR(text, S_IWUGO | S_IRUGO, show_attr_text, set_attr_text);

 static ssize_t show_attr_decimals(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 	int i;
 	int pos;

 	for (i = 0; i < sizeof(mydev->decimals); i++) {
 		pos = sizeof(mydev->decimals) - 1 - i;
 		if (mydev->decimals[i] == 0)
 			buf[pos] = '0';
 		else if (mydev->decimals[i] == 1)
 			buf[pos] = '1';
 		else
 			buf[pos] = 'x';
 	}

 	buf[sizeof(mydev->decimals)] = '\n';
 	return sizeof(mydev->decimals) + 1;
 }

 static ssize_t set_attr_decimals(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 	size_t end = my_memlen(buf, count);
 	int i;

 	if (end > sizeof(mydev->decimals))
 		return -EINVAL;

 	for (i = 0; i < end; i++)
 		if (buf[i] != '0' && buf[i] != '1')
 			return -EINVAL;

 	memset(mydev->decimals, 0, sizeof(mydev->decimals));
 	for (i = 0; i < end; i++)
 		if (buf[i] == '1')
 			mydev->decimals[end-1-i] = 1;

 	update_display_visual(mydev, GFP_KERNEL);

 	return count;
 }

 static DEVICE_ATTR(decimals, S_IWUGO | S_IRUGO,
 	show_attr_decimals, set_attr_decimals);

 static ssize_t show_attr_textmode(struct device *dev,
 	struct device_attribute *attr, char *buf)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 	int i;

 	buf[0] = 0;

 	for (i = 0; display_textmodes[i]; i++) {
 		if (mydev->textmode == i) {
 			strcat(buf, " [");
 			strcat(buf, display_textmodes[i]);
 			strcat(buf, "] ");
 		} else {
 			strcat(buf, " ");
 			strcat(buf, display_textmodes[i]);
 			strcat(buf, " ");
 		}
 	}
 	strcat(buf, "\n");


 	return strlen(buf);
 }

 static ssize_t set_attr_textmode(struct device *dev,
 	struct device_attribute *attr, const char *buf, size_t count)
 {
 	struct usb_interface *intf = to_usb_interface(dev);
 	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
 	int i;

 	for (i = 0; display_textmodes[i]; i++) {
 		if (sysfs_streq(display_textmodes[i], buf)) {
 			mydev->textmode = i;
 			update_display_visual(mydev, GFP_KERNEL);
 			return count;
 		}
 	}

 	return -EINVAL;
 }

 static DEVICE_ATTR(textmode, S_IWUGO | S_IRUGO,
 	show_attr_textmode, set_attr_textmode);


 MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
 MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);

 static struct attribute *dev_attrs[] = {
 	&dev_attr_powered.attr,
 	&dev_attr_text.attr,
 	&dev_attr_textmode.attr,
 	&dev_attr_decimals.attr,
 	&dev_attr_mode_msb.attr,
 	&dev_attr_mode_lsb.attr,
 	NULL
 };

 static struct attribute_group dev_attr_grp = {
 	.attrs = dev_attrs,
 };

 static int sevseg_probe(struct usb_interface *interface,
 	const struct usb_device_id *id)
 {
 	struct usb_device *udev = interface_to_usbdev(interface);
 	struct usb_sevsegdev *mydev = NULL;
 	int rc = -ENOMEM;

 	mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
 	if (mydev == NULL) {
 		dev_err(&interface->dev, "Out of memory\n");
 		goto error_mem;
 	}

 	mydev->udev = usb_get_dev(udev);
 	mydev->intf = interface;
 	usb_set_intfdata(interface, mydev);

 	/*set defaults */
 	mydev->textmode = 0x02; /* ascii mode */
 	mydev->mode_msb = 0x06; /* 6 characters */
 	mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */

 	rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
 	if (rc)
 		goto error;

 	dev_info(&interface->dev, "USB 7 Segment device now attached\n");
 	return 0;

 error:
 	usb_set_intfdata(interface, NULL);
 	usb_put_dev(mydev->udev);
 	kfree(mydev);
 error_mem:
 	return rc;
 }

 static void sevseg_disconnect(struct usb_interface *interface)
 {
 	struct usb_sevsegdev *mydev;

 	mydev = usb_get_intfdata(interface);
 	sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
 	usb_set_intfdata(interface, NULL);
 	usb_put_dev(mydev->udev);
 	kfree(mydev);
 	dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
 }

 static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
 {
 	struct usb_sevsegdev *mydev;

 	mydev = usb_get_intfdata(intf);
 	mydev->shadow_power = 0;

 	return 0;
 }

 static int sevseg_resume(struct usb_interface *intf)
 {
 	struct usb_sevsegdev *mydev;

 	mydev = usb_get_intfdata(intf);
 	mydev->shadow_power = 1;
 	update_display_mode(mydev);
 	update_display_visual(mydev, GFP_NOIO);

 	return 0;
 }

 static int sevseg_reset_resume(struct usb_interface *intf)
 {
 	struct usb_sevsegdev *mydev;

 	mydev = usb_get_intfdata(intf);
 	mydev->shadow_power = 1;
 	update_display_mode(mydev);
 	update_display_visual(mydev, GFP_NOIO);

 	return 0;
 }

 static struct usb_driver sevseg_driver = {
 	.name =		"usbsevseg",
 	.probe =	sevseg_probe,
 	.disconnect =	sevseg_disconnect,
 	.suspend =	sevseg_suspend,
 	.resume =	sevseg_resume,
 	.reset_resume =	sevseg_reset_resume,
 	.id_table =	id_table,
 	.supports_autosuspend = 1,
 };

 static int __init usb_sevseg_init(void)
 {
 	int rc = 0;

 	rc = usb_register(&sevseg_driver);
 	if (rc)
 		err("usb_register failed. Error number %d", rc);
 	return rc;
 }

 static void __exit usb_sevseg_exit(void)
 {
 	usb_deregister(&sevseg_driver);
 }

 module_init(usb_sevseg_init);
 module_exit(usb_sevseg_exit);

 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL");
	/*
	* USB 7 Segment Driver
	*
	* Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
	* Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License as
	* published by the Free Software Foundation, version 2.
	*
	*/

	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/init.h>
	#include <linux/slab.h>
	#include <linux/module.h>
	#include <linux/string.h>
	#include <linux/usb.h>


	#define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
	#define DRIVER_DESC "USB 7 Segment Driver"

	#define VENDOR_ID 0x0fc5
	#define PRODUCT_ID 0x1227
	#define MAXLEN 6

	/* table of devices that work with this driver */
	static struct usb_device_id id_table[] = {
	{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
	{ },
	};
	MODULE_DEVICE_TABLE(usb, id_table);

	/* the different text display modes the device is capable of */
	static char *display_textmodes[] = {"raw", "hex", "ascii", NULL};

	struct usb_sevsegdev {
	struct usb_device *udev;
	struct usb_interface *intf;

	u8 powered;
	u8 mode_msb;
	u8 mode_lsb;
	u8 decimals[MAXLEN];
	u8 textmode;
	u8 text[MAXLEN];
	u16 textlength;

	u8 shadow_power; /* for PM */
	};

	/* sysfs_streq can't replace this completely
	* If the device was in hex mode, and the user wanted a 0,
	* if str commands are used, we would assume the end of string
	* so mem commands are used.
	*/
	inline size_t my_memlen(const char *buf, size_t count)
	{
	if (count > 0 && buf[count-1] == '\n')
	return count - 1;
	else
	return count;
	}

	static void update_display_powered(struct usb_sevsegdev *mydev)
	{
	int rc;

	if (!mydev->shadow_power && mydev->powered) {
	rc = usb_autopm_get_interface(mydev->intf);
	if (rc < 0)
	return;
	}

	rc = usb_control_msg(mydev->udev,
	usb_sndctrlpipe(mydev->udev, 0),
	0x12,
	0x48,
	(80 * 0x100) + 10, /* (power mode) */
	(0x00 * 0x100) + (mydev->powered ? 1 : 0),
	NULL,
	0,
	2000);
	if (rc < 0)
	dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);

	if (mydev->shadow_power && !mydev->powered)
	usb_autopm_put_interface(mydev->intf);
	}

	static void update_display_mode(struct usb_sevsegdev *mydev)
	{
	int rc;

	if(mydev->shadow_power != 1)
	return;

	rc = usb_control_msg(mydev->udev,
	usb_sndctrlpipe(mydev->udev, 0),
	0x12,
	0x48,
	(82 * 0x100) + 10, /* (set mode) */
	(mydev->mode_msb * 0x100) + mydev->mode_lsb,
	NULL,
	0,
	2000);

	if (rc < 0)
	dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
	}

	static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
	{
	int rc;
	int i;
	unsigned char *buffer;
	u8 decimals = 0;

	if(mydev->shadow_power != 1)
	return;

	buffer = kzalloc(MAXLEN, mf);
	if (!buffer) {
	dev_err(&mydev->udev->dev, "out of memory\n");
	return;
	}

	/* The device is right to left, where as you write left to right */
	for (i = 0; i < mydev->textlength; i++)
	buffer[i] = mydev->text[mydev->textlength-1-i];

	rc = usb_control_msg(mydev->udev,
	usb_sndctrlpipe(mydev->udev, 0),
	0x12,
	0x48,
	(85 * 0x100) + 10, /* (write text) */
	(0 * 0x100) + mydev->textmode, /* mode */
	buffer,
	mydev->textlength,
	2000);

	if (rc < 0)
	dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);

	kfree(buffer);

	/* The device is right to left, where as you write left to right */
	for (i = 0; i < sizeof(mydev->decimals); i++)
	decimals \|= mydev->decimals[i] << i;

	rc = usb_control_msg(mydev->udev,
	usb_sndctrlpipe(mydev->udev, 0),
	0x12,
	0x48,
	(86 * 0x100) + 10, /* (set decimal) */
	(0 * 0x100) + decimals, /* decimals */
	NULL,
	0,
	2000);

	if (rc < 0)
	dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
	}

	#define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn) \
	static ssize_t show_attr_##name(struct device *dev, \
	struct device_attribute attr, char buf) \
	{ \
	struct usb_interface *intf = to_usb_interface(dev); \
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf); \
	\
	return sprintf(buf, "%u\n", mydev->name); \
	} \
	\
	static ssize_t set_attr_##name(struct device *dev, \
	struct device_attribute attr, const char buf, size_t count) \
	{ \
	struct usb_interface *intf = to_usb_interface(dev); \
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf); \
	\
	mydev->name = simple_strtoul(buf, NULL, 10); \
	update_fcn(mydev); \
	\
	return count; \
	} \
	static DEVICE_ATTR(name, S_IWUGO \| S_IRUGO, show_attr_##name, set_attr_##name);

	static ssize_t show_attr_text(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);

	return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
	}

	static ssize_t set_attr_text(struct device *dev,
	struct device_attribute attr, const char buf, size_t count)
	{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
	size_t end = my_memlen(buf, count);

	if (end > sizeof(mydev->text))
	return -EINVAL;

	memset(mydev->text, 0, sizeof(mydev->text));
	mydev->textlength = end;

	if (end > 0)
	memcpy(mydev->text, buf, end);

	update_display_visual(mydev, GFP_KERNEL);
	return count;
	}

	static DEVICE_ATTR(text, S_IWUGO \| S_IRUGO, show_attr_text, set_attr_text);

	static ssize_t show_attr_decimals(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
	int i;
	int pos;

	for (i = 0; i < sizeof(mydev->decimals); i++) {
	pos = sizeof(mydev->decimals) - 1 - i;
	if (mydev->decimals[i] == 0)
	buf[pos] = '0';
	else if (mydev->decimals[i] == 1)
	buf[pos] = '1';
	else
	buf[pos] = 'x';
	}

	buf[sizeof(mydev->decimals)] = '\n';
	return sizeof(mydev->decimals) + 1;
	}

	static ssize_t set_attr_decimals(struct device *dev,
	struct device_attribute attr, const char buf, size_t count)
	{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
	size_t end = my_memlen(buf, count);
	int i;

	if (end > sizeof(mydev->decimals))
	return -EINVAL;

	for (i = 0; i < end; i++)
	if (buf[i] != '0' && buf[i] != '1')
	return -EINVAL;

	memset(mydev->decimals, 0, sizeof(mydev->decimals));
	for (i = 0; i < end; i++)
	if (buf[i] == '1')
	mydev->decimals[end-1-i] = 1;

	update_display_visual(mydev, GFP_KERNEL);

	return count;
	}

	static DEVICE_ATTR(decimals, S_IWUGO \| S_IRUGO,
	show_attr_decimals, set_attr_decimals);

	static ssize_t show_attr_textmode(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
	int i;

	buf[0] = 0;

	for (i = 0; display_textmodes[i]; i++) {
	if (mydev->textmode == i) {
	strcat(buf, " [");
	strcat(buf, display_textmodes[i]);
	strcat(buf, "] ");
	} else {
	strcat(buf, " ");
	strcat(buf, display_textmodes[i]);
	strcat(buf, " ");
	}
	}
	strcat(buf, "\n");


	return strlen(buf);
	}

	static ssize_t set_attr_textmode(struct device *dev,
	struct device_attribute attr, const char buf, size_t count)
	{
	struct usb_interface *intf = to_usb_interface(dev);
	struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
	int i;

	for (i = 0; display_textmodes[i]; i++) {
	if (sysfs_streq(display_textmodes[i], buf)) {
	mydev->textmode = i;
	update_display_visual(mydev, GFP_KERNEL);
	return count;
	}
	}

	return -EINVAL;
	}

	static DEVICE_ATTR(textmode, S_IWUGO \| S_IRUGO,
	show_attr_textmode, set_attr_textmode);


	MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
	MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
	MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);

	static struct attribute *dev_attrs[] = {
	&dev_attr_powered.attr,
	&dev_attr_text.attr,
	&dev_attr_textmode.attr,
	&dev_attr_decimals.attr,
	&dev_attr_mode_msb.attr,
	&dev_attr_mode_lsb.attr,
	NULL
	};

	static struct attribute_group dev_attr_grp = {
	.attrs = dev_attrs,
	};

	static int sevseg_probe(struct usb_interface *interface,
	const struct usb_device_id *id)
	{
	struct usb_device *udev = interface_to_usbdev(interface);
	struct usb_sevsegdev *mydev = NULL;
	int rc = -ENOMEM;

	mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
	if (mydev == NULL) {
	dev_err(&interface->dev, "Out of memory\n");
	goto error_mem;
	}

	mydev->udev = usb_get_dev(udev);
	mydev->intf = interface;
	usb_set_intfdata(interface, mydev);

	/set defaults /
	mydev->textmode = 0x02; /* ascii mode */
	mydev->mode_msb = 0x06; /* 6 characters */
	mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */

	rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
	if (rc)
	goto error;

	dev_info(&interface->dev, "USB 7 Segment device now attached\n");
	return 0;

	error:
	usb_set_intfdata(interface, NULL);
	usb_put_dev(mydev->udev);
	kfree(mydev);
	error_mem:
	return rc;
	}

	static void sevseg_disconnect(struct usb_interface *interface)
	{
	struct usb_sevsegdev *mydev;

	mydev = usb_get_intfdata(interface);
	sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
	usb_set_intfdata(interface, NULL);
	usb_put_dev(mydev->udev);
	kfree(mydev);
	dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
	}

	static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
	{
	struct usb_sevsegdev *mydev;

	mydev = usb_get_intfdata(intf);
	mydev->shadow_power = 0;

	return 0;
	}

	static int sevseg_resume(struct usb_interface *intf)
	{
	struct usb_sevsegdev *mydev;

	mydev = usb_get_intfdata(intf);
	mydev->shadow_power = 1;
	update_display_mode(mydev);
	update_display_visual(mydev, GFP_NOIO);

	return 0;
	}

	static int sevseg_reset_resume(struct usb_interface *intf)
	{
	struct usb_sevsegdev *mydev;

	mydev = usb_get_intfdata(intf);
	mydev->shadow_power = 1;
	update_display_mode(mydev);
	update_display_visual(mydev, GFP_NOIO);

	return 0;
	}

	static struct usb_driver sevseg_driver = {
	.name = "usbsevseg",
	.probe = sevseg_probe,
	.disconnect = sevseg_disconnect,
	.suspend = sevseg_suspend,
	.resume = sevseg_resume,
	.reset_resume = sevseg_reset_resume,
	.id_table = id_table,
	.supports_autosuspend = 1,
	};

	static int __init usb_sevseg_init(void)
	{
	int rc = 0;

	rc = usb_register(&sevseg_driver);
	if (rc)
	err("usb_register failed. Error number %d", rc);
	return rc;
	}

	static void __exit usb_sevseg_exit(void)
	{
	usb_deregister(&sevseg_driver);
	}

	module_init(usb_sevseg_init);
	module_exit(usb_sevseg_exit);

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