asus_oled.c 19 KB
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816
/*
 *  Asus OLED USB driver
 *
 *  Copyright (C) 2007,2008 Jakub Schmidtke (sjakub@gmail.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; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 *
 *
 *  This module is based on usbled and asus-laptop modules.
 *
 *
 *  Asus OLED support is based on asusoled program taken from
 *  <http://lapsus.berlios.de/asus_oled.html>.
 *
 *
 */

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

#define ASUS_OLED_VERSION		"0.04-dev"
#define ASUS_OLED_NAME			"asus-oled"
#define ASUS_OLED_UNDERSCORE_NAME	"asus_oled"

#define ASUS_OLED_ERROR			"Asus OLED Display Error: "

#define ASUS_OLED_STATIC		's'
#define ASUS_OLED_ROLL			'r'
#define ASUS_OLED_FLASH			'f'

#define ASUS_OLED_MAX_WIDTH		1792
#define ASUS_OLED_DISP_HEIGHT		32
#define ASUS_OLED_PACKET_BUF_SIZE	256

#define USB_VENDOR_ID_ASUS      0x0b05
#define USB_DEVICE_ID_ASUS_LCM      0x1726
#define USB_DEVICE_ID_ASUS_LCM2     0x175b

MODULE_AUTHOR("Jakub Schmidtke, sjakub@gmail.com");
MODULE_DESCRIPTION("Asus OLED Driver v" ASUS_OLED_VERSION);
MODULE_LICENSE("GPL");

static struct class *oled_class;
static int oled_num;

static uint start_off;

module_param(start_off, uint, 0644);

MODULE_PARM_DESC(start_off,
		 "Set to 1 to switch off OLED display after it is attached");

enum oled_pack_mode {
	PACK_MODE_G1,
	PACK_MODE_G50,
	PACK_MODE_LAST
};

struct oled_dev_desc_str {
	uint16_t		idVendor;
	uint16_t		idProduct;
	/* width of display */
	uint16_t		devWidth;
	/* formula to be used while packing the picture */
	enum oled_pack_mode	packMode;
	const char		*devDesc;
};

/* table of devices that work with this driver */
static const struct usb_device_id id_table[] = {
	/* Asus G1/G2 (and variants)*/
	{ USB_DEVICE(USB_VENDOR_ID_ASUS, USB_DEVICE_ID_ASUS_LCM) },
	/* Asus G50V (and possibly others - G70? G71?)*/
	{ USB_DEVICE(USB_VENDOR_ID_ASUS, USB_DEVICE_ID_ASUS_LCM2) },
	{ },
};

/* parameters of specific devices */
static struct oled_dev_desc_str oled_dev_desc_table[] = {
	{ USB_VENDOR_ID_ASUS, USB_DEVICE_ID_ASUS_LCM, 128, PACK_MODE_G1,
		"G1/G2" },
	{ USB_VENDOR_ID_ASUS, USB_DEVICE_ID_ASUS_LCM2, 256, PACK_MODE_G50,
		"G50" },
	{ },
};

MODULE_DEVICE_TABLE(usb, id_table);

struct asus_oled_header {
	uint8_t		magic1;
	uint8_t		magic2;
	uint8_t		flags;
	uint8_t		value3;
	uint8_t		buffer1;
	uint8_t		buffer2;
	uint8_t		value6;
	uint8_t		value7;
	uint8_t		value8;
	uint8_t		padding2[7];
} __attribute((packed));

struct asus_oled_packet {
	struct asus_oled_header		header;
	uint8_t				bitmap[ASUS_OLED_PACKET_BUF_SIZE];
} __attribute((packed));

struct asus_oled_dev {
	struct usb_device       *udev;
	uint8_t			pic_mode;
	uint16_t		dev_width;
	enum oled_pack_mode	pack_mode;
	size_t			height;
	size_t			width;
	size_t			x_shift;
	size_t			y_shift;
	size_t			buf_offs;
	uint8_t			last_val;
	size_t			buf_size;
	char			*buf;
	uint8_t			enabled;
	struct device		*dev;
};

static void setup_packet_header(struct asus_oled_packet *packet, char flags,
			 char value3, char buffer1, char buffer2, char value6,
			 char value7, char value8)
{
	memset(packet, 0, sizeof(struct asus_oled_header));
	packet->header.magic1 = 0x55;
	packet->header.magic2 = 0xaa;
	packet->header.flags = flags;
	packet->header.value3 = value3;
	packet->header.buffer1 = buffer1;
	packet->header.buffer2 = buffer2;
	packet->header.value6 = value6;
	packet->header.value7 = value7;
	packet->header.value8 = value8;
}

static void enable_oled(struct asus_oled_dev *odev, uint8_t enabl)
{
	int a;
	int retval;
	int act_len;
	struct asus_oled_packet *packet;

	packet = kzalloc(sizeof(struct asus_oled_packet), GFP_KERNEL);

	if (!packet) {
		dev_err(&odev->udev->dev, "out of memory\n");
		return;
	}

	setup_packet_header(packet, 0x20, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00);

	if (enabl)
		packet->bitmap[0] = 0xaf;
	else
		packet->bitmap[0] = 0xae;

	for (a = 0; a < 1; a++) {
		retval = usb_bulk_msg(odev->udev,
			usb_sndbulkpipe(odev->udev, 2),
			packet,
			sizeof(struct asus_oled_header) + 1,
			&act_len,
			-1);

		if (retval)
			dev_dbg(&odev->udev->dev, "retval = %d\n", retval);
	}

	odev->enabled = enabl;

	kfree(packet);
}

static ssize_t set_enabled(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t count)
{
	struct usb_interface *intf = to_usb_interface(dev);
	struct asus_oled_dev *odev = usb_get_intfdata(intf);
	unsigned long value;
	if (kstrtoul(buf, 10, &value))
		return -EINVAL;

	enable_oled(odev, value);

	return count;
}

static ssize_t class_set_enabled(struct device *device,
				 struct device_attribute *attr,
				 const char *buf, size_t count)
{
	struct asus_oled_dev *odev =
		(struct asus_oled_dev *) dev_get_drvdata(device);
	unsigned long value;

	if (kstrtoul(buf, 10, &value))
		return -EINVAL;

	enable_oled(odev, value);

	return count;
}

static ssize_t get_enabled(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	struct usb_interface *intf = to_usb_interface(dev);
	struct asus_oled_dev *odev = usb_get_intfdata(intf);

	return sprintf(buf, "%d\n", odev->enabled);
}

static ssize_t class_get_enabled(struct device *device,
				 struct device_attribute *attr, char *buf)
{
	struct asus_oled_dev *odev =
		(struct asus_oled_dev *) dev_get_drvdata(device);

	return sprintf(buf, "%d\n", odev->enabled);
}

static void send_packets(struct usb_device *udev,
			 struct asus_oled_packet *packet,
			 char *buf, uint8_t p_type, size_t p_num)
{
	size_t i;
	int act_len;

	for (i = 0; i < p_num; i++) {
		int retval;

		switch (p_type) {
		case ASUS_OLED_ROLL:
			setup_packet_header(packet, 0x40, 0x80, p_num,
					    i + 1, 0x00, 0x01, 0xff);
			break;
		case ASUS_OLED_STATIC:
			setup_packet_header(packet, 0x10 + i, 0x80, 0x01,
					    0x01, 0x00, 0x01, 0x00);
			break;
		case ASUS_OLED_FLASH:
			setup_packet_header(packet, 0x10 + i, 0x80, 0x01,
					    0x01, 0x00, 0x00, 0xff);
			break;
		}

		memcpy(packet->bitmap, buf + (ASUS_OLED_PACKET_BUF_SIZE*i),
		       ASUS_OLED_PACKET_BUF_SIZE);

		retval = usb_bulk_msg(udev, usb_sndctrlpipe(udev, 2),
				      packet, sizeof(struct asus_oled_packet),
				      &act_len, -1);

		if (retval)
			dev_dbg(&udev->dev, "retval = %d\n", retval);
	}
}

static void send_packet(struct usb_device *udev,
			struct asus_oled_packet *packet,
			size_t offset, size_t len, char *buf, uint8_t b1,
			uint8_t b2, uint8_t b3, uint8_t b4, uint8_t b5,
			uint8_t b6) {
	int retval;
	int act_len;

	setup_packet_header(packet, b1, b2, b3, b4, b5, b6, 0x00);
	memcpy(packet->bitmap, buf + offset, len);

	retval = usb_bulk_msg(udev,
			      usb_sndctrlpipe(udev, 2),
			      packet,
			      sizeof(struct asus_oled_packet),
			      &act_len,
			      -1);

	if (retval)
		dev_dbg(&udev->dev, "retval = %d\n", retval);
}


static void send_packets_g50(struct usb_device *udev,
			     struct asus_oled_packet *packet, char *buf)
{
	send_packet(udev, packet,     0, 0x100, buf,
		    0x10, 0x00, 0x02, 0x01, 0x00, 0x01);
	send_packet(udev, packet, 0x100, 0x080, buf,
		    0x10, 0x00, 0x02, 0x02, 0x80, 0x00);

	send_packet(udev, packet, 0x180, 0x100, buf,
		    0x11, 0x00, 0x03, 0x01, 0x00, 0x01);
	send_packet(udev, packet, 0x280, 0x100, buf,
		    0x11, 0x00, 0x03, 0x02, 0x00, 0x01);
	send_packet(udev, packet, 0x380, 0x080, buf,
		    0x11, 0x00, 0x03, 0x03, 0x80, 0x00);
}


static void send_data(struct asus_oled_dev *odev)
{
	size_t packet_num = odev->buf_size / ASUS_OLED_PACKET_BUF_SIZE;
	struct asus_oled_packet *packet;

	packet = kzalloc(sizeof(struct asus_oled_packet), GFP_KERNEL);

	if (!packet) {
		dev_err(&odev->udev->dev, "out of memory\n");
		return;
	}

	if (odev->pack_mode == PACK_MODE_G1) {
		/* When sending roll-mode data the display updated only
		   first packet.  I have no idea why, but when static picture
		   is sent just before rolling picture everything works fine. */
		if (odev->pic_mode == ASUS_OLED_ROLL)
			send_packets(odev->udev, packet, odev->buf,
				     ASUS_OLED_STATIC, 2);

		/* Only ROLL mode can use more than 2 packets.*/
		if (odev->pic_mode != ASUS_OLED_ROLL && packet_num > 2)
			packet_num = 2;

		send_packets(odev->udev, packet, odev->buf,
			     odev->pic_mode, packet_num);
	} else if (odev->pack_mode == PACK_MODE_G50) {
		send_packets_g50(odev->udev, packet, odev->buf);
	}

	kfree(packet);
}

static int append_values(struct asus_oled_dev *odev, uint8_t val, size_t count)
{
	while (count-- > 0 && val) {
		size_t x = odev->buf_offs % odev->width;
		size_t y = odev->buf_offs / odev->width;
		size_t i;

		x += odev->x_shift;
		y += odev->y_shift;

		switch (odev->pack_mode) {
		case PACK_MODE_G1:
			/* i = (x/128)*640 + 127 - x + (y/8)*128;
			   This one for 128 is the same, but might be better
			   for different widths? */
			i = (x/odev->dev_width)*640 +
				odev->dev_width - 1 - x +
				(y/8)*odev->dev_width;
			break;

		case PACK_MODE_G50:
			i =  (odev->dev_width - 1 - x)/8 + y*odev->dev_width/8;
			break;

		default:
			i = 0;
			printk(ASUS_OLED_ERROR "Unknown OLED Pack Mode: %d!\n",
			       odev->pack_mode);
			break;
		}

		if (i >= odev->buf_size) {
			printk(ASUS_OLED_ERROR "Buffer overflow! Report a bug:"
			       "offs: %d >= %d i: %d (x: %d y: %d)\n",
			       (int) odev->buf_offs, (int) odev->buf_size,
			       (int) i, (int) x, (int) y);
			return -EIO;
		}

		switch (odev->pack_mode) {
		case PACK_MODE_G1:
			odev->buf[i] &= ~(1<<(y%8));
			break;

		case PACK_MODE_G50:
			odev->buf[i] &= ~(1<<(x%8));
			break;

		default:
			/* cannot get here; stops gcc complaining*/
			;
		}

		odev->last_val = val;
		odev->buf_offs++;
	}

	return 0;
}

static ssize_t odev_set_picture(struct asus_oled_dev *odev,
				const char *buf, size_t count)
{
	size_t offs = 0, max_offs;

	if (count < 1)
		return 0;

	if (tolower(buf[0]) == 'b') {
		/* binary mode, set the entire memory*/

		size_t i;

		odev->buf_size = (odev->dev_width * ASUS_OLED_DISP_HEIGHT) / 8;

		kfree(odev->buf);
		odev->buf = kmalloc(odev->buf_size, GFP_KERNEL);
		if (odev->buf == NULL) {
			odev->buf_size = 0;
			printk(ASUS_OLED_ERROR "Out of memory!\n");
			return -ENOMEM;
		}

		memset(odev->buf, 0xff, odev->buf_size);

		for (i = 1; i < count && i <= 32 * 32; i++) {
			odev->buf[i-1] = buf[i];
			odev->buf_offs = i-1;
		}

		odev->width = odev->dev_width / 8;
		odev->height = ASUS_OLED_DISP_HEIGHT;
		odev->x_shift = 0;
		odev->y_shift = 0;
		odev->last_val =  0;

		send_data(odev);

		return count;
	}

	if (buf[0] == '<') {
		size_t i;
		size_t w = 0, h = 0;
		size_t w_mem, h_mem;

		if (count < 10 || buf[2] != ':')
			goto error_header;


		switch (tolower(buf[1])) {
		case ASUS_OLED_STATIC:
		case ASUS_OLED_ROLL:
		case ASUS_OLED_FLASH:
			odev->pic_mode = buf[1];
			break;
		default:
			printk(ASUS_OLED_ERROR "Wrong picture mode: '%c'.\n",
			       buf[1]);
			return -EIO;
			break;
		}

		for (i = 3; i < count; ++i) {
			if (buf[i] >= '0' && buf[i] <= '9') {
				w = 10*w + (buf[i] - '0');

				if (w > ASUS_OLED_MAX_WIDTH)
					goto error_width;
			} else if (tolower(buf[i]) == 'x') {
				break;
			} else {
				goto error_width;
			}
		}

		for (++i; i < count; ++i) {
			if (buf[i] >= '0' && buf[i] <= '9') {
				h = 10*h + (buf[i] - '0');

				if (h > ASUS_OLED_DISP_HEIGHT)
					goto error_height;
			} else if (tolower(buf[i]) == '>') {
				break;
			} else {
				goto error_height;
			}
		}

		if (w < 1 || w > ASUS_OLED_MAX_WIDTH)
			goto error_width;

		if (h < 1 || h > ASUS_OLED_DISP_HEIGHT)
			goto error_height;

		if (i >= count || buf[i] != '>')
			goto error_header;

		offs = i+1;

		if (w % (odev->dev_width) != 0)
			w_mem = (w/(odev->dev_width) + 1)*(odev->dev_width);
		else
			w_mem = w;

		if (h < ASUS_OLED_DISP_HEIGHT)
			h_mem = ASUS_OLED_DISP_HEIGHT;
		else
			h_mem = h;

		odev->buf_size = w_mem * h_mem / 8;

		kfree(odev->buf);
		odev->buf = kmalloc(odev->buf_size, GFP_KERNEL);

		if (odev->buf == NULL) {
			odev->buf_size = 0;
			printk(ASUS_OLED_ERROR "Out of memory!\n");
			return -ENOMEM;
		}

		memset(odev->buf, 0xff, odev->buf_size);

		odev->buf_offs = 0;
		odev->width = w;
		odev->height = h;
		odev->x_shift = 0;
		odev->y_shift = 0;
		odev->last_val = 0;

		if (odev->pic_mode == ASUS_OLED_FLASH) {
			if (h < ASUS_OLED_DISP_HEIGHT/2)
				odev->y_shift = (ASUS_OLED_DISP_HEIGHT/2 - h)/2;
		} else {
			if (h < ASUS_OLED_DISP_HEIGHT)
				odev->y_shift = (ASUS_OLED_DISP_HEIGHT - h)/2;
		}

		if (w < (odev->dev_width))
			odev->x_shift = ((odev->dev_width) - w)/2;
	}

	max_offs = odev->width * odev->height;

	while (offs < count && odev->buf_offs < max_offs) {
		int ret = 0;

		if (buf[offs] == '1' || buf[offs] == '#') {
			ret = append_values(odev, 1, 1);
			if (ret < 0)
				return ret;
		} else if (buf[offs] == '0' || buf[offs] == ' ') {
			ret = append_values(odev, 0, 1);
			if (ret < 0)
				return ret;
		} else if (buf[offs] == '\n') {
			/* New line detected. Lets assume, that all characters
			   till the end of the line were equal to the last
			   character in this line.*/
			if (odev->buf_offs % odev->width != 0)
				ret = append_values(odev, odev->last_val,
						    odev->width -
						    (odev->buf_offs %
						     odev->width));
			if (ret < 0)
				return ret;
		}

		offs++;
	}

	if (odev->buf_offs >= max_offs)
		send_data(odev);

	return count;

error_width:
	printk(ASUS_OLED_ERROR "Wrong picture width specified.\n");
	return -EIO;

error_height:
	printk(ASUS_OLED_ERROR "Wrong picture height specified.\n");
	return -EIO;

error_header:
	printk(ASUS_OLED_ERROR "Wrong picture header.\n");
	return -EIO;
}

static ssize_t set_picture(struct device *dev, struct device_attribute *attr,
			   const char *buf, size_t count)
{
	struct usb_interface *intf = to_usb_interface(dev);

	return odev_set_picture(usb_get_intfdata(intf), buf, count);
}

static ssize_t class_set_picture(struct device *device,
				 struct device_attribute *attr,
				 const char *buf, size_t count)
{
	return odev_set_picture((struct asus_oled_dev *)
				dev_get_drvdata(device), buf, count);
}

#define ASUS_OLED_DEVICE_ATTR(_file)		dev_attr_asus_oled_##_file

static DEVICE_ATTR(asus_oled_enabled, S_IWUSR | S_IRUGO,
		   get_enabled, set_enabled);
static DEVICE_ATTR(asus_oled_picture, S_IWUSR , NULL, set_picture);

static DEVICE_ATTR(enabled, S_IWUSR | S_IRUGO,
		   class_get_enabled, class_set_enabled);
static DEVICE_ATTR(picture, S_IWUSR, NULL, class_set_picture);

static int asus_oled_probe(struct usb_interface *interface,
			   const struct usb_device_id *id)
{
	struct usb_device *udev = interface_to_usbdev(interface);
	struct asus_oled_dev *odev = NULL;
	int retval = -ENOMEM;
	uint16_t dev_width = 0;
	enum oled_pack_mode pack_mode = PACK_MODE_LAST;
	const struct oled_dev_desc_str *dev_desc = oled_dev_desc_table;
	const char *desc = NULL;

	if (!id) {
		/* Even possible? Just to make sure...*/
		dev_err(&interface->dev, "No usb_device_id provided!\n");
		return -ENODEV;
	}

	for (; dev_desc->idVendor; dev_desc++) {
		if (dev_desc->idVendor == id->idVendor
		    && dev_desc->idProduct == id->idProduct) {
			dev_width = dev_desc->devWidth;
			desc = dev_desc->devDesc;
			pack_mode = dev_desc->packMode;
			break;
		}
	}

	if (!desc || dev_width < 1 || pack_mode == PACK_MODE_LAST) {
		dev_err(&interface->dev,
			"Missing or incomplete device description!\n");
		return -ENODEV;
	}

	odev = kzalloc(sizeof(struct asus_oled_dev), GFP_KERNEL);

	if (odev == NULL) {
		dev_err(&interface->dev, "Out of memory\n");
		return -ENOMEM;
	}

	odev->udev = usb_get_dev(udev);
	odev->pic_mode = ASUS_OLED_STATIC;
	odev->dev_width = dev_width;
	odev->pack_mode = pack_mode;
	odev->height = 0;
	odev->width = 0;
	odev->x_shift = 0;
	odev->y_shift = 0;
	odev->buf_offs = 0;
	odev->buf_size = 0;
	odev->last_val = 0;
	odev->buf = NULL;
	odev->enabled = 1;
	odev->dev = NULL;

	usb_set_intfdata(interface, odev);

	retval = device_create_file(&interface->dev,
				    &ASUS_OLED_DEVICE_ATTR(enabled));
	if (retval)
		goto err_files;

	retval = device_create_file(&interface->dev,
				    &ASUS_OLED_DEVICE_ATTR(picture));
	if (retval)
		goto err_files;

	odev->dev = device_create(oled_class, &interface->dev, MKDEV(0, 0),
				  NULL, "oled_%d", ++oled_num);

	if (IS_ERR(odev->dev)) {
		retval = PTR_ERR(odev->dev);
		goto err_files;
	}

	dev_set_drvdata(odev->dev, odev);

	retval = device_create_file(odev->dev, &dev_attr_enabled);
	if (retval)
		goto err_class_enabled;

	retval = device_create_file(odev->dev, &dev_attr_picture);
	if (retval)
		goto err_class_picture;

	dev_info(&interface->dev,
		 "Attached Asus OLED device: %s [width %u, pack_mode %d]\n",
		 desc, odev->dev_width, odev->pack_mode);

	if (start_off)
		enable_oled(odev, 0);

	return 0;

err_class_picture:
	device_remove_file(odev->dev, &dev_attr_picture);

err_class_enabled:
	device_remove_file(odev->dev, &dev_attr_enabled);
	device_unregister(odev->dev);

err_files:
	device_remove_file(&interface->dev, &ASUS_OLED_DEVICE_ATTR(enabled));
	device_remove_file(&interface->dev, &ASUS_OLED_DEVICE_ATTR(picture));

	usb_set_intfdata(interface, NULL);
	usb_put_dev(odev->udev);
	kfree(odev);

	return retval;
}

static void asus_oled_disconnect(struct usb_interface *interface)
{
	struct asus_oled_dev *odev;

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

	device_remove_file(odev->dev, &dev_attr_picture);
	device_remove_file(odev->dev, &dev_attr_enabled);
	device_unregister(odev->dev);

	device_remove_file(&interface->dev, &ASUS_OLED_DEVICE_ATTR(picture));
	device_remove_file(&interface->dev, &ASUS_OLED_DEVICE_ATTR(enabled));

	usb_put_dev(odev->udev);

	kfree(odev->buf);

	kfree(odev);

	dev_info(&interface->dev, "Disconnected Asus OLED device\n");
}

static struct usb_driver oled_driver = {
	.name =		ASUS_OLED_NAME,
	.probe =	asus_oled_probe,
	.disconnect =	asus_oled_disconnect,
	.id_table =	id_table,
};

static CLASS_ATTR_STRING(version, S_IRUGO,
			ASUS_OLED_UNDERSCORE_NAME " " ASUS_OLED_VERSION);

static int __init asus_oled_init(void)
{
	int retval = 0;
	oled_class = class_create(THIS_MODULE, ASUS_OLED_UNDERSCORE_NAME);

	if (IS_ERR(oled_class)) {
		err("Error creating " ASUS_OLED_UNDERSCORE_NAME " class");
		return PTR_ERR(oled_class);
	}

	retval = class_create_file(oled_class, &class_attr_version.attr);
	if (retval) {
		err("Error creating class version file");
		goto error;
	}

	retval = usb_register(&oled_driver);

	if (retval) {
		err("usb_register failed. Error number %d", retval);
		goto error;
	}

	return retval;

error:
	class_destroy(oled_class);
	return retval;
}

static void __exit asus_oled_exit(void)
{
	class_remove_file(oled_class, &class_attr_version.attr);
	class_destroy(oled_class);

	usb_deregister(&oled_driver);
}

module_init(asus_oled_init);
module_exit(asus_oled_exit);