/*
 * printer.c  Version 0.12
 *
 * Copyright (c) 1999 Michael Gee	<michael@linuxspecific.com>
 * Copyright (c) 1999 Pavel Machek	<pavel@suse.cz>
 * Copyright (c) 2000 Randy Dunlap	<randy.dunlap@intel.com>
 * Copyright (c) 2000 Vojtech Pavlik	<vojtech@suse.cz>
 # Copyright (c) 2001 Pete Zaitcev	<zaitcev@redhat.com>
 # Copyright (c) 2001 David Paschal	<paschal@rcsis.com>
 *
 * USB Printer Device Class driver for USB printers and printer cables
 *
 * Sponsored by SuSE
 *
 * ChangeLog:
 *	v0.1 - thorough cleaning, URBification, almost a rewrite
 *	v0.2 - some more cleanups
 *	v0.3 - cleaner again, waitqueue fixes
 *	v0.4 - fixes in unidirectional mode
 *	v0.5 - add DEVICE_ID string support
 *	v0.6 - never time out
 *	v0.7 - fixed bulk-IN read and poll (David Paschal)
 *	v0.8 - add devfs support
 *	v0.9 - fix unplug-while-open paths
 *	v0.10- remove sleep_on, fix error on oom (oliver@neukum.org)
 *	v0.11 - add proto_bias option (Pete Zaitcev)
 *	v0.12 - add hpoj.sourceforge.net ioctls (David Paschal)
 */

/*
 * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/smp_lock.h>
#include <linux/signal.h>
#include <linux/poll.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/lp.h>
#include <linux/devfs_fs_kernel.h>
#undef DEBUG
#include <linux/usb.h>

/*
 * Version Information
 */
#define DRIVER_VERSION "v0.12"
#define DRIVER_AUTHOR "Michael Gee, Pavel Machek, Vojtech Pavlik, Randy Dunlap, Pete Zaitcev, David Paschal"
#define DRIVER_DESC "USB Printer Device Class driver"

#define USBLP_BUF_SIZE		8192
#define DEVICE_ID_SIZE		1024

/* ioctls: */
#define LPGETSTATUS		0x060b		/* same as in drivers/char/lp.c */
#define IOCNR_GET_DEVICE_ID		1
#define IOCNR_GET_PROTOCOLS		2
#define IOCNR_SET_PROTOCOL		3
#define IOCNR_HP_SET_CHANNEL		4
#define IOCNR_GET_BUS_ADDRESS		5
#define IOCNR_GET_VID_PID		6
/* Get device_id string: */
#define LPIOC_GET_DEVICE_ID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_DEVICE_ID, len)
/* The following ioctls were added for http://hpoj.sourceforge.net: */
/* Get two-int array:
 * [0]=current protocol (1=7/1/1, 2=7/1/2, 3=7/1/3),
 * [1]=supported protocol mask (mask&(1<<n)!=0 means 7/1/n supported): */
#define LPIOC_GET_PROTOCOLS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_PROTOCOLS, len)
/* Set protocol (arg: 1=7/1/1, 2=7/1/2, 3=7/1/3): */
#define LPIOC_SET_PROTOCOL _IOC(_IOC_WRITE, 'P', IOCNR_SET_PROTOCOL, 0)
/* Set channel number (HP Vendor-specific command): */
#define LPIOC_HP_SET_CHANNEL _IOC(_IOC_WRITE, 'P', IOCNR_HP_SET_CHANNEL, 0)
/* Get two-int array: [0]=bus number, [1]=device address: */
#define LPIOC_GET_BUS_ADDRESS(len) _IOC(_IOC_READ, 'P', IOCNR_GET_BUS_ADDRESS, len)
/* Get two-int array: [0]=vendor ID, [1]=product ID: */
#define LPIOC_GET_VID_PID(len) _IOC(_IOC_READ, 'P', IOCNR_GET_VID_PID, len)

/*
 * A DEVICE_ID string may include the printer's serial number.
 * It should end with a semi-colon (';').
 * An example from an HP 970C DeskJet printer is (this is one long string,
 * with the serial number changed):
MFG:HEWLETT-PACKARD;MDL:DESKJET 970C;CMD:MLC,PCL,PML;CLASS:PRINTER;DESCRIPTION:Hewlett-Packard DeskJet 970C;SERN:US970CSEPROF;VSTATUS:$HB0$NC0,ff,DN,IDLE,CUT,K1,C0,DP,NR,KP000,CP027;VP:0800,FL,B0;VJ:                    ;
 */

/*
 * USB Printer Requests
 */

#define USBLP_REQ_GET_ID			0x00
#define USBLP_REQ_GET_STATUS			0x01
#define USBLP_REQ_RESET				0x02
#define USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST	0x00	/* HP Vendor-specific */

#ifdef CONFIG_USB_DYNAMIC_MINORS
#define USBLP_MINORS		256
#else
#define USBLP_MINORS		16
#endif
#define USBLP_MINOR_BASE	0

#define USBLP_WRITE_TIMEOUT	(5*HZ)			/* 5 seconds */

#define USBLP_FIRST_PROTOCOL	1
#define USBLP_LAST_PROTOCOL	3
#define USBLP_MAX_PROTOCOLS	(USBLP_LAST_PROTOCOL+1)

struct usblp {
	struct usb_device 	*dev;			/* USB device */
	devfs_handle_t		devfs;			/* devfs device */
	struct semaphore	sem;			/* locks this struct, especially "dev" */
	char			*buf;		/* writeurb->transfer_buffer */
	struct urb		*readurb, *writeurb;	/* The urbs */
	wait_queue_head_t	wait;			/* Zzzzz ... */
	int			readcount;		/* Counter for reads */
	int			ifnum;			/* Interface number */
	/* Alternate-setting numbers and endpoints for each protocol
	 * (7/1/{index=1,2,3}) that the device supports: */
	struct {
		int				alt_setting;
		struct usb_endpoint_descriptor	*epwrite;
		struct usb_endpoint_descriptor	*epread;
	}			protocol[USBLP_MAX_PROTOCOLS];
	int			current_protocol;
	int			minor;			/* minor number of device */
	int			wcomplete;		/* writing is completed */
	int			rcomplete;		/* reading is completed */
	unsigned int		quirks;			/* quirks flags */
	unsigned char		used;			/* True if open */
	unsigned char		bidir;			/* interface is bidirectional */
	unsigned char		*device_id_string;	/* IEEE 1284 DEVICE ID string (ptr) */
							/* first 2 bytes are (big-endian) length */
};

#ifdef DEBUG
static void usblp_dump(struct usblp *usblp) {
	int p;

	dbg("usblp=0x%p", usblp);
	dbg("dev=0x%p", usblp->dev);
	dbg("devfs=0x%p", usblp->devfs);
	dbg("buf=0x%p", usblp->buf);
	dbg("readcount=%d", usblp->readcount);
	dbg("ifnum=%d", usblp->ifnum);
    for (p = USBLP_FIRST_PROTOCOL; p <= USBLP_LAST_PROTOCOL; p++) {
	dbg("protocol[%d].alt_setting=%d", p, usblp->protocol[p].alt_setting);
	dbg("protocol[%d].epwrite=%p", p, usblp->protocol[p].epwrite);
	dbg("protocol[%d].epread=%p", p, usblp->protocol[p].epread);
    }
	dbg("current_protocol=%d", usblp->current_protocol);
	dbg("minor=%d", usblp->minor);
	dbg("wcomplete=%d", usblp->wcomplete);
	dbg("rcomplete=%d", usblp->rcomplete);
	dbg("quirks=%d", usblp->quirks);
	dbg("used=%d", usblp->used);
	dbg("bidir=%d", usblp->bidir);
	dbg("device_id_string=\"%s\"",
		usblp->device_id_string ?
			usblp->device_id_string + 2 :
			(unsigned char *)"(null)");
}
#endif

extern devfs_handle_t usb_devfs_handle;			/* /dev/usb dir. */

static struct usblp *usblp_table[USBLP_MINORS];

/* Quirks: various printer quirks are handled by this table & its flags. */

struct quirk_printer_struct {
	__u16 vendorId;
	__u16 productId;
	unsigned int quirks;
};

#define USBLP_QUIRK_BIDIR	0x1	/* reports bidir but requires unidirectional mode (no INs/reads) */
#define USBLP_QUIRK_USB_INIT	0x2	/* needs vendor USB init string */

static struct quirk_printer_struct quirk_printers[] = {
	{ 0x03f0, 0x0004, USBLP_QUIRK_BIDIR }, /* HP DeskJet 895C */
	{ 0x03f0, 0x0104, USBLP_QUIRK_BIDIR }, /* HP DeskJet 880C */
	{ 0x03f0, 0x0204, USBLP_QUIRK_BIDIR }, /* HP DeskJet 815C */
	{ 0x03f0, 0x0304, USBLP_QUIRK_BIDIR }, /* HP DeskJet 810C/812C */
	{ 0x03f0, 0x0404, USBLP_QUIRK_BIDIR }, /* HP DeskJet 830C */
	{ 0x03f0, 0x0504, USBLP_QUIRK_BIDIR }, /* HP DeskJet 885C */
	{ 0x03f0, 0x0604, USBLP_QUIRK_BIDIR }, /* HP DeskJet 840C */   
	{ 0x03f0, 0x0804, USBLP_QUIRK_BIDIR }, /* HP DeskJet 816C */   
	{ 0x03f0, 0x1104, USBLP_QUIRK_BIDIR }, /* HP Deskjet 959C */
	{ 0x0409, 0xefbe, USBLP_QUIRK_BIDIR }, /* NEC Picty900 (HP OEM) */
	{ 0x0409, 0xbef4, USBLP_QUIRK_BIDIR }, /* NEC Picty760 (HP OEM) */
	{ 0x0409, 0xf0be, USBLP_QUIRK_BIDIR }, /* NEC Picty920 (HP OEM) */
	{ 0x0409, 0xf1be, USBLP_QUIRK_BIDIR }, /* NEC Picty800 (HP OEM) */
	{ 0, 0 }
};

static int usblp_select_alts(struct usblp *usblp);
static int usblp_set_protocol(struct usblp *usblp, int protocol);
static int usblp_cache_device_id_string(struct usblp *usblp);

/* forward reference to make our lives easier */
extern struct usb_driver usblp_driver;

/*
 * Functions for usblp control messages.
 */

static int usblp_ctrl_msg(struct usblp *usblp, int request, int type, int dir, int recip, int value, void *buf, int len)
{
	int retval = usb_control_msg(usblp->dev,
		dir ? usb_rcvctrlpipe(usblp->dev, 0) : usb_sndctrlpipe(usblp->dev, 0),
		request, type | dir | recip, value, usblp->ifnum, buf, len, USBLP_WRITE_TIMEOUT);
	dbg("usblp_control_msg: rq: 0x%02x dir: %d recip: %d value: %d len: %#x result: %d",
		request, !!dir, recip, value, len, retval);
	return retval < 0 ? retval : 0;
}

#define usblp_read_status(usblp, status)\
	usblp_ctrl_msg(usblp, USBLP_REQ_GET_STATUS, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, 0, status, 1)
#define usblp_get_id(usblp, config, id, maxlen)\
	usblp_ctrl_msg(usblp, USBLP_REQ_GET_ID, USB_TYPE_CLASS, USB_DIR_IN, USB_RECIP_INTERFACE, config, id, maxlen)
#define usblp_reset(usblp)\
	usblp_ctrl_msg(usblp, USBLP_REQ_RESET, USB_TYPE_CLASS, USB_DIR_OUT, USB_RECIP_OTHER, 0, NULL, 0)

#define usblp_hp_channel_change_request(usblp, channel, buffer) \
	usblp_ctrl_msg(usblp, USBLP_REQ_HP_CHANNEL_CHANGE_REQUEST, USB_TYPE_VENDOR, USB_DIR_IN, USB_RECIP_INTERFACE, channel, buffer, 1)

/*
 * See the description for usblp_select_alts() below for the usage
 * explanation.  Look into your /proc/bus/usb/devices and dmesg in
 * case of any trouble.
 */
static int proto_bias = -1;

/*
 * URB callback.
 */

static void usblp_bulk_read(struct urb *urb)
{
	struct usblp *usblp = urb->context;

	if (!usblp || !usblp->dev || !usblp->used)
		return;

	if (unlikely(urb->status))
		warn("usblp%d: nonzero read/write bulk status received: %d",
			usblp->minor, urb->status);
	usblp->rcomplete = 1;
	wake_up_interruptible(&usblp->wait);
}

static void usblp_bulk_write(struct urb *urb)
{
	struct usblp *usblp = urb->context;

	if (!usblp || !usblp->dev || !usblp->used)
		return;

	if (unlikely(urb->status))
		warn("usblp%d: nonzero read/write bulk status received: %d",
			usblp->minor, urb->status);
	usblp->wcomplete = 1;
	wake_up_interruptible(&usblp->wait);
}

/*
 * Get and print printer errors.
 */

static char *usblp_messages[] = { "ok", "out of paper", "off-line", "on fire" };

static int usblp_check_status(struct usblp *usblp, int err)
{
	unsigned char status, newerr = 0;
	int error;

	error = usblp_read_status (usblp, &status);
	if (error < 0) {
		err("usblp%d: error %d reading printer status",
			usblp->minor, error);
		return 0;
	}

	if (~status & LP_PERRORP) {
		newerr = 3;
		if (status & LP_POUTPA) newerr = 1;
		if (~status & LP_PSELECD) newerr = 2;
	}

	if (newerr != err)
		info("usblp%d: %s", usblp->minor, usblp_messages[newerr]);

	return newerr;
}

/*
 * File op functions.
 */

static int usblp_open(struct inode *inode, struct file *file)
{
	int minor = minor(inode->i_rdev) - USBLP_MINOR_BASE;
	struct usblp *usblp;
	int retval;

	if (minor < 0 || minor >= USBLP_MINORS)
		return -ENODEV;

	lock_kernel();
	usblp  = usblp_table[minor];

	retval = -ENODEV;
	if (!usblp || !usblp->dev)
		goto out;

	retval = -EBUSY;
	if (usblp->used)
		goto out;

	/*
	 * TODO: need to implement LP_ABORTOPEN + O_NONBLOCK as in drivers/char/lp.c ???
	 * This is #if 0-ed because we *don't* want to fail an open
	 * just because the printer is off-line.
	 */
#if 0
	if ((retval = usblp_check_status(usblp, 0))) {
		retval = retval > 1 ? -EIO : -ENOSPC;
		goto out;
	}
#else
	retval = 0;
#endif

	usblp->used = 1;
	file->private_data = usblp;

	usblp->writeurb->transfer_buffer_length = 0;
	usblp->writeurb->status = 0;
	usblp->wcomplete = 1; /* we begin writeable */
	usblp->rcomplete = 0;

	if (usblp->bidir) {
		usblp->readcount = 0;
		usblp->readurb->dev = usblp->dev;
		if (usb_submit_urb(usblp->readurb, GFP_KERNEL) < 0) {
			retval = -EIO;
			usblp->used = 0;
			file->private_data = NULL;
		}
	}
out:
	unlock_kernel();
	return retval;
}

static void usblp_cleanup (struct usblp *usblp)
{
	devfs_unregister (usblp->devfs);
	usblp_table [usblp->minor] = NULL;
	usb_deregister_dev (&usblp_driver, 1, usblp->minor);
	info("usblp%d: removed", usblp->minor);

	kfree (usblp->writeurb->transfer_buffer);
	kfree (usblp->device_id_string);
	usb_free_urb(usblp->writeurb);