[mirror_ubuntu-bionic-kernel.git] / drivers / parport / daisy.c

/*
 * IEEE 1284.3 Parallel port daisy chain and multiplexor code
 * 
 * Copyright (C) 1999, 2000  Tim Waugh <tim@cyberelk.demon.co.uk>
 *
 * 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.
 *
 * ??-12-1998: Initial implementation.
 * 31-01-1999: Make port-cloning transparent.
 * 13-02-1999: Move DeviceID technique from parport_probe.
 * 13-03-1999: Get DeviceID from non-IEEE 1284.3 devices too.
 * 22-02-2000: Count devices that are actually detected.
 *
 * Any part of this program may be used in documents licensed under
 * the GNU Free Documentation License, Version 1.1 or any later version
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/parport.h>
#include <linux/delay.h>
#include <linux/sched.h>

#include <asm/current.h>
#include <asm/uaccess.h>

#undef DEBUG

#ifdef DEBUG
#define DPRINTK(stuff...) printk(stuff)
#else
#define DPRINTK(stuff...)
#endif

static struct daisydev {
	struct daisydev *next;
	struct parport *port;
	int daisy;
	int devnum;
} *topology = NULL;
static DEFINE_SPINLOCK(topology_lock);

static int numdevs = 0;

/* Forward-declaration of lower-level functions. */
static int mux_present(struct parport *port);
static int num_mux_ports(struct parport *port);
static int select_port(struct parport *port);
static int assign_addrs(struct parport *port);

/* Add a device to the discovered topology. */
static void add_dev(int devnum, struct parport *port, int daisy)
{
	struct daisydev *newdev, **p;
	newdev = kmalloc(sizeof(struct daisydev), GFP_KERNEL);
	if (newdev) {
		newdev->port = port;
		newdev->daisy = daisy;
		newdev->devnum = devnum;
		spin_lock(&topology_lock);
		for (p = &topology; *p && (*p)->devnum<devnum; p = &(*p)->next)
			;
		newdev->next = *p;
		*p = newdev;
		spin_unlock(&topology_lock);
	}
}

/* Clone a parport (actually, make an alias). */
static struct parport *clone_parport(struct parport *real, int muxport)
{
	struct parport *extra = parport_register_port(real->base,
						       real->irq,
						       real->dma,
						       real->ops);
	if (extra) {
		extra->portnum = real->portnum;
		extra->physport = real;
		extra->muxport = muxport;
		real->slaves[muxport-1] = extra;
	}

	return extra;
}

/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains.
 * Return value is number of devices actually detected. */
int parport_daisy_init(struct parport *port)
{
	int detected = 0;
	char *deviceid;
	static const char *th[] = { /*0*/"th", "st", "nd", "rd", "th" };
	int num_ports;
	int i;
	int last_try = 0;

again:
	/* Because this is called before any other devices exist,
	 * we don't have to claim exclusive access.  */

	/* If mux present on normal port, need to create new
	 * parports for each extra port. */
	if (port->muxport < 0 && mux_present(port) &&
	    /* don't be fooled: a mux must have 2 or 4 ports. */
	    ((num_ports = num_mux_ports(port)) == 2 || num_ports == 4)) {
		/* Leave original as port zero. */
		port->muxport = 0;
		printk(KERN_INFO
			"%s: 1st (default) port of %d-way multiplexor\n",
			port->name, num_ports);
		for (i = 1; i < num_ports; i++) {
			/* Clone the port. */
			struct parport *extra = clone_parport(port, i);
			if (!extra) {
				if (signal_pending(current))
					break;

				schedule();
				continue;
			}

			printk(KERN_INFO
				"%s: %d%s port of %d-way multiplexor on %s\n",
				extra->name, i + 1, th[i + 1], num_ports,
				port->name);

			/* Analyse that port too.  We won't recurse
			   forever because of the 'port->muxport < 0'
			   test above. */
			parport_daisy_init(extra);
		}
	}

	if (port->muxport >= 0)
		select_port(port);

	parport_daisy_deselect_all(port);
	detected += assign_addrs(port);

	/* Count the potential legacy device at the end. */
	add_dev(numdevs++, port, -1);

	/* Find out the legacy device's IEEE 1284 device ID. */
	deviceid = kmalloc(1024, GFP_KERNEL);
	if (deviceid) {
		if (parport_device_id(numdevs - 1, deviceid, 1024) > 2)
			detected++;

		kfree(deviceid);
	}

	if (!detected && !last_try) {
		/* No devices were detected.  Perhaps they are in some
                   funny state; let's try to reset them and see if
                   they wake up. */
		parport_daisy_fini(port);
		parport_write_control(port, PARPORT_CONTROL_SELECT);
		udelay(50);
		parport_write_control(port,
				       PARPORT_CONTROL_SELECT |
				       PARPORT_CONTROL_INIT);
		udelay(50);
		last_try = 1;
		goto again;
	}

	return detected;
}

/* Forget about devices on a physical port. */
void parport_daisy_fini(struct parport *port)
{
	struct daisydev **p;

	spin_lock(&topology_lock);
	p = &topology;
	while (*p) {
		struct daisydev *dev = *p;
		if (dev->port != port) {
			p = &dev->next;
			continue;
		}
		*p = dev->next;
		kfree(dev);
	}

	/* Gaps in the numbering could be handled better.  How should
           someone enumerate through all IEEE1284.3 devices in the
           topology?. */
	if (!topology) numdevs = 0;
	spin_unlock(&topology_lock);
	return;
}

/**
 *	parport_open - find a device by canonical device number
 *	@devnum: canonical device number
 *	@name: name to associate with the device
 *	@pf: preemption callback
 *	@kf: kick callback
 *	@irqf: interrupt handler
 *	@flags: registration flags
 *	@handle: driver data
 *
 *	This function is similar to parport_register_device(), except
 *	that it locates a device by its number rather than by the port
 *	it is attached to.
 *
 *	All parameters except for @devnum are the same as for
 *	parport_register_device().  The return value is the same as
 *	for parport_register_device().
 **/

struct pardevice *parport_open(int devnum, const char *name,
				int (*pf) (void *), void (*kf) (void *),
				void (*irqf) (int, void *),
				int flags, void *handle)
{
	struct daisydev *p = topology;
	struct parport *port;
	struct pardevice *dev;
	int daisy;

	spin_lock(&topology_lock);
	while (p && p->devnum != devnum)
		p = p->next;

	if (!p) {
		spin_unlock(&topology_lock);
		return NULL;
	}

	daisy = p->daisy;
	port = parport_get_port(p->port);
	spin_unlock(&topology_lock);

	dev = parport_register_device(port, name, pf, kf,
				       irqf, flags, handle);
	parport_put_port(port);
	if (!dev)
		return NULL;

	dev->daisy = daisy;

	/* Check that there really is a device to select. */
	if (daisy >= 0) {
		int selected;
		parport_claim_or_block(dev);
		selected = port->daisy;
		parport_release(dev);

		if (selected != daisy) {
			/* No corresponding device. */
			parport_unregister_device(dev);
			return NULL;
		}
	}

	return dev;
}

/**
 *	parport_close - close a device opened with parport_open()
 *	@dev: device to close
 *
 *	This is to parport_open() as parport_unregister_device() is to
 *	parport_register_device().
 **/

void parport_close(struct pardevice *dev)
{
	parport_unregister_device(dev);
}

/* Send a daisy-chain-style CPP command packet. */
static int cpp_daisy(struct parport *port, int cmd)
{
	unsigned char s;

	parport_data_forward(port);
	parport_write_data(port, 0xaa); udelay(2);
	parport_write_data(port, 0x55); udelay(2);
	parport_write_data(port, 0x00); udelay(2);
	parport_write_data(port, 0xff); udelay(2);
	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
					  | PARPORT_STATUS_PAPEROUT
					  | PARPORT_STATUS_SELECT
					  | PARPORT_STATUS_ERROR);
	if (s != (PARPORT_STATUS_BUSY
		  | PARPORT_STATUS_PAPEROUT
		  | PARPORT_STATUS_SELECT
		  | PARPORT_STATUS_ERROR)) {
		DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff(%02x)\n",
			 port->name, s);
		return -ENXIO;
	}

	parport_write_data(port, 0x87); udelay(2);
	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
					  | PARPORT_STATUS_PAPEROUT
					  | PARPORT_STATUS_SELECT
					  | PARPORT_STATUS_ERROR);
	if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
		DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff87(%02x)\n",
			 port->name, s);
		return -ENXIO;
	}

	parport_write_data(port, 0x78); udelay(2);
	parport_write_data(port, cmd); udelay(2);
	parport_frob_control(port,
			      PARPORT_CONTROL_STROBE,
			      PARPORT_CONTROL_STROBE);
	udelay(1);
	s = parport_read_status(port);
	parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
	udelay(1);
	parport_write_data(port, 0xff); udelay(2);

	return s;
}

/* Send a mux-style CPP command packet. */
static int cpp_mux(struct parport *port, int cmd)
{
	unsigned char s;
	int rc;

	parport_data_forward(port);
	parport_write_data(port, 0xaa); udelay(2);
	parport_write_data(port, 0x55); udelay(2);
	parport_write_data(port, 0xf0); udelay(2);
	parport_write_data(port, 0x0f); udelay(2);
	parport_write_data(port, 0x52); udelay(2);
	parport_write_data(port, 0xad); udelay(2);
	parport_write_data(port, cmd); udelay(2);

	s = parport_read_status(port);
	if (!(s & PARPORT_STATUS_ACK)) {
		DPRINTK(KERN_DEBUG "%s: cpp_mux: aa55f00f52ad%02x(%02x)\n",
			 port->name, cmd, s);
		return -EIO;
	}

	rc = (((s & PARPORT_STATUS_SELECT   ? 1 : 0) << 0) |
	      ((s & PARPORT_STATUS_PAPEROUT ? 1 : 0) << 1) |
	      ((s & PARPORT_STATUS_BUSY     ? 0 : 1) << 2) |
	      ((s & PARPORT_STATUS_ERROR    ? 0 : 1) << 3));

	return rc;
}

void parport_daisy_deselect_all(struct parport *port)
{
	cpp_daisy(port, 0x30);
}

int parport_daisy_select(struct parport *port, int daisy, int mode)
{
	switch (mode)
	{
		// For these modes we should switch to EPP mode:
		case IEEE1284_MODE_EPP:
		case IEEE1284_MODE_EPPSL:
		case IEEE1284_MODE_EPPSWE:
			return !(cpp_daisy(port, 0x20 + daisy) &
				 PARPORT_STATUS_ERROR);

		// For these modes we should switch to ECP mode:
		case IEEE1284_MODE_ECP:
		case IEEE1284_MODE_ECPRLE:
		case IEEE1284_MODE_ECPSWE: 
			return !(cpp_daisy(port, 0xd0 + daisy) &
				 PARPORT_STATUS_ERROR);

		// Nothing was told for BECP in Daisy chain specification.
		// May be it's wise to use ECP?
		case IEEE1284_MODE_BECP:
		// Others use compat mode
		case IEEE1284_MODE_NIBBLE:
		case IEEE1284_MODE_BYTE:
		case IEEE1284_MODE_COMPAT:
		default:
			return !(cpp_daisy(port, 0xe0 + daisy) &
				 PARPORT_STATUS_ERROR);
	}
}

static int mux_present(struct parport *port)
{
	return cpp_mux(port, 0x51) == 3;
}

static int num_mux_ports(struct parport *port)
{
	return cpp_mux(port, 0x58);
}

static int select_port(struct parport *port)
{
	int muxport = port->muxport;
	return cpp_mux(port, 0x60 + muxport) == muxport;
}

static int assign_addrs(struct parport *port)
{
	unsigned char s;
	unsigned char daisy;
	int thisdev = numdevs;
	int detected;
	char *deviceid;

	parport_data_forward(port);
	parport_write_data(port, 0xaa); udelay(2);
	parport_write_data(port, 0x55); udelay(2);
	parport_write_data(port, 0x00); udelay(2);
	parport_write_data(port, 0xff); udelay(2);
	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
					  | PARPORT_STATUS_PAPEROUT
					  | PARPORT_STATUS_SELECT
					  | PARPORT_STATUS_ERROR);
	if (s != (PARPORT_STATUS_BUSY
		  | PARPORT_STATUS_PAPEROUT
		  | PARPORT_STATUS_SELECT
		  | PARPORT_STATUS_ERROR)) {
		DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff(%02x)\n",
			 port->name, s);
		return 0;
	}

	parport_write_data(port, 0x87); udelay(2);
	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
					  | PARPORT_STATUS_PAPEROUT
					  | PARPORT_STATUS_SELECT
					  | PARPORT_STATUS_ERROR);
	if (s != (PARPORT_STATUS_SELECT | PARPORT_STATUS_ERROR)) {
		DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff87(%02x)\n",
			 port->name, s);
		return 0;
	}

	parport_write_data(port, 0x78); udelay(2);
	s = parport_read_status(port);

	for (daisy = 0;
	     (s & (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT))
		     == (PARPORT_STATUS_PAPEROUT|PARPORT_STATUS_SELECT)
		     && daisy < 4;
	     ++daisy) {
		parport_write_data(port, daisy);
		udelay(2);
		parport_frob_control(port,
				      PARPORT_CONTROL_STROBE,
				      PARPORT_CONTROL_STROBE);
		udelay(1);
		parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
		udelay(1);

		add_dev(numdevs++, port, daisy);

		/* See if this device thought it was the last in the
		 * chain. */
		if (!(s & PARPORT_STATUS_BUSY))
			break;

		/* We are seeing pass through status now. We see
		   last_dev from next device or if last_dev does not
		   work status lines from some non-daisy chain
		   device. */
		s = parport_read_status(port);
	}

	parport_write_data(port, 0xff); udelay(2);
	detected = numdevs - thisdev;
	DPRINTK(KERN_DEBUG "%s: Found %d daisy-chained devices\n", port->name,
		 detected);

	/* Ask the new devices to introduce themselves. */
	deviceid = kmalloc(1024, GFP_KERNEL);
	if (!deviceid) return 0;

	for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
		parport_device_id(thisdev, deviceid, 1024);

	kfree(deviceid);
	return detected;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* IEEE 1284.3 Parallel port daisy chain and multiplexor code
	3	*
	4	* Copyright (C) 1999, 2000 Tim Waugh <tim@cyberelk.demon.co.uk>
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*
	11	* ??-12-1998: Initial implementation.
	12	* 31-01-1999: Make port-cloning transparent.
	13	* 13-02-1999: Move DeviceID technique from parport_probe.
	14	* 13-03-1999: Get DeviceID from non-IEEE 1284.3 devices too.
	15	* 22-02-2000: Count devices that are actually detected.
	16	*
	17	* Any part of this program may be used in documents licensed under
	18	* the GNU Free Documentation License, Version 1.1 or any later version
	19	* published by the Free Software Foundation.
	20	*/
	21
	22	#include <linux/module.h>
	23	#include <linux/parport.h>
	24	#include <linux/delay.h>
	25	#include <linux/sched.h>
	26
	27	#include <asm/current.h>
	28	#include <asm/uaccess.h>
	29
	30	#undef DEBUG
	31
	32	#ifdef DEBUG
d32ccc43	33	#define DPRINTK(stuff...) printk(stuff)
1da177e4 LT	34	#else
	35	#define DPRINTK(stuff...)
	36	#endif
	37
	38	static struct daisydev {
	39	struct daisydev *next;
	40	struct parport *port;
	41	int daisy;
	42	int devnum;
	43	} *topology = NULL;
	44	static DEFINE_SPINLOCK(topology_lock);
	45
	46	static int numdevs = 0;
	47
	48	/* Forward-declaration of lower-level functions. */
d32ccc43 MM	49	static int mux_present(struct parport *port);
	50	static int num_mux_ports(struct parport *port);
	51	static int select_port(struct parport *port);
	52	static int assign_addrs(struct parport *port);
1da177e4 LT	53
1da177e4 LT	54	/* Add a device to the discovered topology. */
d32ccc43	55	static void add_dev(int devnum, struct parport *port, int daisy)
1da177e4 LT	56	{
1da177e4 LT	57	struct daisydev newdev, *p;
d32ccc43	58	newdev = kmalloc(sizeof(struct daisydev), GFP_KERNEL);
1da177e4 LT	59	if (newdev) {
	60	newdev->port = port;
	61	newdev->daisy = daisy;
	62	newdev->devnum = devnum;
	63	spin_lock(&topology_lock);
	64	for (p = &topology; p && (p)->devnum<devnum; p = &(*p)->next)
	65	;
	66	newdev->next = *p;
	67	*p = newdev;
	68	spin_unlock(&topology_lock);
	69	}
	70	}
	71
	72	/* Clone a parport (actually, make an alias). */
d32ccc43	73	static struct parport clone_parport(struct parport real, int muxport)
1da177e4	74	{
d32ccc43	75	struct parport *extra = parport_register_port(real->base,
1da177e4 LT	76	real->irq,
	77	real->dma,
	78	real->ops);
	79	if (extra) {
	80	extra->portnum = real->portnum;
	81	extra->physport = real;
	82	extra->muxport = muxport;
	83	real->slaves[muxport-1] = extra;
	84	}
	85
	86	return extra;
	87	}
	88
	89	/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains.
	90	* Return value is number of devices actually detected. */
d32ccc43	91	int parport_daisy_init(struct parport *port)
1da177e4 LT	92	{
	93	int detected = 0;
	94	char *deviceid;
	95	static const char th[] = { /0*/"th", "st", "nd", "rd", "th" };
	96	int num_ports;
	97	int i;
	98	int last_try = 0;
	99
	100	again:
	101	/* Because this is called before any other devices exist,
	102	* we don't have to claim exclusive access. */
	103
	104	/* If mux present on normal port, need to create new
	105	* parports for each extra port. */
d32ccc43	106	if (port->muxport < 0 && mux_present(port) &&
1da177e4	107	/* don't be fooled: a mux must have 2 or 4 ports. */
d32ccc43	108	((num_ports = num_mux_ports(port)) == 2 \|\| num_ports == 4)) {
1da177e4 LT	109	/* Leave original as port zero. */
1da177e4 LT	110	port->muxport = 0;
d32ccc43	111	printk(KERN_INFO
1da177e4 LT	112	"%s: 1st (default) port of %d-way multiplexor\n",
	113	port->name, num_ports);
	114	for (i = 1; i < num_ports; i++) {
	115	/* Clone the port. */
d32ccc43	116	struct parport *extra = clone_parport(port, i);
1da177e4	117	if (!extra) {
d32ccc43	118	if (signal_pending(current))
1da177e4 LT	119	break;
1da177e4 LT	120
d32ccc43	121	schedule();
1da177e4 LT	122	continue;
	123	}
	124
d32ccc43	125	printk(KERN_INFO
1da177e4 LT	126	"%s: %d%s port of %d-way multiplexor on %s\n",
	127	extra->name, i + 1, th[i + 1], num_ports,
	128	port->name);
	129
	130	/* Analyse that port too. We won't recurse
	131	forever because of the 'port->muxport < 0'
	132	test above. */
	133	parport_daisy_init(extra);
	134	}
	135	}
	136
	137	if (port->muxport >= 0)
d32ccc43	138	select_port(port);
1da177e4	139
d32ccc43 MM	140	parport_daisy_deselect_all(port);
d32ccc43 MM	141	detected += assign_addrs(port);
1da177e4 LT	142
1da177e4 LT	143	/* Count the potential legacy device at the end. */
d32ccc43	144	add_dev(numdevs++, port, -1);
1da177e4 LT	145
1da177e4 LT	146	/* Find out the legacy device's IEEE 1284 device ID. */
d32ccc43	147	deviceid = kmalloc(1024, GFP_KERNEL);
1da177e4	148	if (deviceid) {
d32ccc43	149	if (parport_device_id(numdevs - 1, deviceid, 1024) > 2)
1da177e4 LT	150	detected++;
1da177e4 LT	151
d32ccc43	152	kfree(deviceid);
1da177e4 LT	153	}
	154
	155	if (!detected && !last_try) {
	156	/* No devices were detected. Perhaps they are in some
	157	funny state; let's try to reset them and see if
	158	they wake up. */
d32ccc43 MM	159	parport_daisy_fini(port);
	160	parport_write_control(port, PARPORT_CONTROL_SELECT);
	161	udelay(50);
	162	parport_write_control(port,
1da177e4 LT	163	PARPORT_CONTROL_SELECT \|
1da177e4 LT	164	PARPORT_CONTROL_INIT);
d32ccc43	165	udelay(50);
1da177e4 LT	166	last_try = 1;
	167	goto again;
	168	}
	169
	170	return detected;
	171	}
	172
	173	/* Forget about devices on a physical port. */
d32ccc43	174	void parport_daisy_fini(struct parport *port)
1da177e4 LT	175	{
	176	struct daisydev **p;
	177
	178	spin_lock(&topology_lock);
	179	p = &topology;
	180	while (*p) {
	181	struct daisydev dev = p;
	182	if (dev->port != port) {
	183	p = &dev->next;
	184	continue;
	185	}
	186	*p = dev->next;
	187	kfree(dev);
	188	}
	189
	190	/* Gaps in the numbering could be handled better. How should
	191	someone enumerate through all IEEE1284.3 devices in the
	192	topology?. */
	193	if (!topology) numdevs = 0;
	194	spin_unlock(&topology_lock);
	195	return;
	196	}
	197
	198	/**
	199	* parport_open - find a device by canonical device number
	200	* @devnum: canonical device number
	201	* @name: name to associate with the device
	202	* @pf: preemption callback
	203	* @kf: kick callback
	204	* @irqf: interrupt handler
	205	* @flags: registration flags
	206	* @handle: driver data
	207	*
	208	* This function is similar to parport_register_device(), except
	209	* that it locates a device by its number rather than by the port
	210	* it is attached to.
	211	*
	212	* All parameters except for @devnum are the same as for
	213	* parport_register_device(). The return value is the same as
	214	* for parport_register_device().
	215	**/
	216
d32ccc43	217	struct pardevice parport_open(int devnum, const char name,
1da177e4	218	int (pf) (void ), void (kf) (void ),
7d12e780	219	void (irqf) (int, void ),
1da177e4 LT	220	int flags, void *handle)
	221	{
	222	struct daisydev *p = topology;
	223	struct parport *port;
	224	struct pardevice *dev;
	225	int daisy;
	226
	227	spin_lock(&topology_lock);
	228	while (p && p->devnum != devnum)
	229	p = p->next;
	230
	231	if (!p) {
	232	spin_unlock(&topology_lock);
	233	return NULL;
	234	}
	235
	236	daisy = p->daisy;
	237	port = parport_get_port(p->port);
	238	spin_unlock(&topology_lock);
	239
d32ccc43	240	dev = parport_register_device(port, name, pf, kf,
1da177e4 LT	241	irqf, flags, handle);
	242	parport_put_port(port);
	243	if (!dev)
	244	return NULL;
	245
	246	dev->daisy = daisy;
	247
	248	/* Check that there really is a device to select. */
	249	if (daisy >= 0) {
	250	int selected;
d32ccc43	251	parport_claim_or_block(dev);
1da177e4	252	selected = port->daisy;
d32ccc43	253	parport_release(dev);
1da177e4	254
c29a75ed	255	if (selected != daisy) {
1da177e4	256	/* No corresponding device. */
d32ccc43	257	parport_unregister_device(dev);
1da177e4 LT	258	return NULL;
	259	}
	260	}
	261
	262	return dev;
	263	}
	264
	265	/**
	266	* parport_close - close a device opened with parport_open()
	267	* @dev: device to close
	268	*
	269	* This is to parport_open() as parport_unregister_device() is to
	270	* parport_register_device().
	271	**/
	272
d32ccc43	273	void parport_close(struct pardevice *dev)
1da177e4	274	{
d32ccc43	275	parport_unregister_device(dev);
1da177e4 LT	276	}
1da177e4 LT	277
1da177e4	278	/* Send a daisy-chain-style CPP command packet. */
d32ccc43	279	static int cpp_daisy(struct parport *port, int cmd)
1da177e4 LT	280	{
	281	unsigned char s;
	282
d32ccc43 MM	283	parport_data_forward(port);
	284	parport_write_data(port, 0xaa); udelay(2);
	285	parport_write_data(port, 0x55); udelay(2);
	286	parport_write_data(port, 0x00); udelay(2);
	287	parport_write_data(port, 0xff); udelay(2);
	288	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	289	\| PARPORT_STATUS_PAPEROUT
	290	\| PARPORT_STATUS_SELECT
	291	\| PARPORT_STATUS_ERROR);
	292	if (s != (PARPORT_STATUS_BUSY
	293	\| PARPORT_STATUS_PAPEROUT
	294	\| PARPORT_STATUS_SELECT
	295	\| PARPORT_STATUS_ERROR)) {
d32ccc43	296	DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff(%02x)\n",
1da177e4 LT	297	port->name, s);
	298	return -ENXIO;
	299	}
	300
d32ccc43 MM	301	parport_write_data(port, 0x87); udelay(2);
d32ccc43 MM	302	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	303	\| PARPORT_STATUS_PAPEROUT
	304	\| PARPORT_STATUS_SELECT
	305	\| PARPORT_STATUS_ERROR);
	306	if (s != (PARPORT_STATUS_SELECT \| PARPORT_STATUS_ERROR)) {
d32ccc43	307	DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff87(%02x)\n",
1da177e4 LT	308	port->name, s);
	309	return -ENXIO;
	310	}
	311
d32ccc43 MM	312	parport_write_data(port, 0x78); udelay(2);
	313	parport_write_data(port, cmd); udelay(2);
	314	parport_frob_control(port,
1da177e4 LT	315	PARPORT_CONTROL_STROBE,
1da177e4 LT	316	PARPORT_CONTROL_STROBE);
d32ccc43 MM	317	udelay(1);
	318	s = parport_read_status(port);
	319	parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
	320	udelay(1);
	321	parport_write_data(port, 0xff); udelay(2);
1da177e4 LT	322
	323	return s;
	324	}
	325
	326	/* Send a mux-style CPP command packet. */
d32ccc43	327	static int cpp_mux(struct parport *port, int cmd)
1da177e4 LT	328	{
	329	unsigned char s;
	330	int rc;
	331
d32ccc43 MM	332	parport_data_forward(port);
	333	parport_write_data(port, 0xaa); udelay(2);
	334	parport_write_data(port, 0x55); udelay(2);
	335	parport_write_data(port, 0xf0); udelay(2);
	336	parport_write_data(port, 0x0f); udelay(2);
	337	parport_write_data(port, 0x52); udelay(2);
	338	parport_write_data(port, 0xad); udelay(2);
	339	parport_write_data(port, cmd); udelay(2);
1da177e4	340
d32ccc43	341	s = parport_read_status(port);
1da177e4	342	if (!(s & PARPORT_STATUS_ACK)) {
d32ccc43	343	DPRINTK(KERN_DEBUG "%s: cpp_mux: aa55f00f52ad%02x(%02x)\n",
1da177e4 LT	344	port->name, cmd, s);
	345	return -EIO;
	346	}
	347
	348	rc = (((s & PARPORT_STATUS_SELECT ? 1 : 0) << 0) \|
	349	((s & PARPORT_STATUS_PAPEROUT ? 1 : 0) << 1) \|
	350	((s & PARPORT_STATUS_BUSY ? 0 : 1) << 2) \|
	351	((s & PARPORT_STATUS_ERROR ? 0 : 1) << 3));
	352
	353	return rc;
	354	}
	355
d32ccc43	356	void parport_daisy_deselect_all(struct parport *port)
1da177e4	357	{
d32ccc43	358	cpp_daisy(port, 0x30);
1da177e4 LT	359	}
1da177e4 LT	360
d32ccc43	361	int parport_daisy_select(struct parport *port, int daisy, int mode)
1da177e4 LT	362	{
	363	switch (mode)
	364	{
	365	// For these modes we should switch to EPP mode:
	366	case IEEE1284_MODE_EPP:
	367	case IEEE1284_MODE_EPPSL:
	368	case IEEE1284_MODE_EPPSWE:
d32ccc43	369	return !(cpp_daisy(port, 0x20 + daisy) &
7c9cc3be	370	PARPORT_STATUS_ERROR);
1da177e4 LT	371
	372	// For these modes we should switch to ECP mode:
	373	case IEEE1284_MODE_ECP:
	374	case IEEE1284_MODE_ECPRLE:
	375	case IEEE1284_MODE_ECPSWE:
d32ccc43	376	return !(cpp_daisy(port, 0xd0 + daisy) &
7c9cc3be	377	PARPORT_STATUS_ERROR);
1da177e4 LT	378
	379	// Nothing was told for BECP in Daisy chain specification.
	380	// May be it's wise to use ECP?
	381	case IEEE1284_MODE_BECP:
	382	// Others use compat mode
	383	case IEEE1284_MODE_NIBBLE:
	384	case IEEE1284_MODE_BYTE:
	385	case IEEE1284_MODE_COMPAT:
	386	default:
d32ccc43	387	return !(cpp_daisy(port, 0xe0 + daisy) &
7c9cc3be	388	PARPORT_STATUS_ERROR);
1da177e4 LT	389	}
	390	}
	391
d32ccc43	392	static int mux_present(struct parport *port)
1da177e4	393	{
d32ccc43	394	return cpp_mux(port, 0x51) == 3;
1da177e4 LT	395	}
1da177e4 LT	396
d32ccc43	397	static int num_mux_ports(struct parport *port)
1da177e4	398	{
d32ccc43	399	return cpp_mux(port, 0x58);
1da177e4 LT	400	}
1da177e4 LT	401
d32ccc43	402	static int select_port(struct parport *port)
1da177e4 LT	403	{
1da177e4 LT	404	int muxport = port->muxport;
d32ccc43	405	return cpp_mux(port, 0x60 + muxport) == muxport;
1da177e4 LT	406	}
1da177e4 LT	407
d32ccc43	408	static int assign_addrs(struct parport *port)
1da177e4	409	{
310c8c32	410	unsigned char s;
1da177e4 LT	411	unsigned char daisy;
	412	int thisdev = numdevs;
	413	int detected;
	414	char *deviceid;
	415
d32ccc43 MM	416	parport_data_forward(port);
	417	parport_write_data(port, 0xaa); udelay(2);
	418	parport_write_data(port, 0x55); udelay(2);
	419	parport_write_data(port, 0x00); udelay(2);
	420	parport_write_data(port, 0xff); udelay(2);
	421	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	422	\| PARPORT_STATUS_PAPEROUT
	423	\| PARPORT_STATUS_SELECT
	424	\| PARPORT_STATUS_ERROR);
	425	if (s != (PARPORT_STATUS_BUSY
	426	\| PARPORT_STATUS_PAPEROUT
	427	\| PARPORT_STATUS_SELECT
	428	\| PARPORT_STATUS_ERROR)) {
d32ccc43	429	DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff(%02x)\n",
1da177e4 LT	430	port->name, s);
	431	return 0;
	432	}
	433
d32ccc43 MM	434	parport_write_data(port, 0x87); udelay(2);
d32ccc43 MM	435	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	436	\| PARPORT_STATUS_PAPEROUT
	437	\| PARPORT_STATUS_SELECT
	438	\| PARPORT_STATUS_ERROR);
	439	if (s != (PARPORT_STATUS_SELECT \| PARPORT_STATUS_ERROR)) {
d32ccc43	440	DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff87(%02x)\n",
1da177e4 LT	441	port->name, s);
	442	return 0;
	443	}
	444
d32ccc43 MM	445	parport_write_data(port, 0x78); udelay(2);
d32ccc43 MM	446	s = parport_read_status(port);
1da177e4	447
310c8c32 MK	448	for (daisy = 0;
	449	(s & (PARPORT_STATUS_PAPEROUT\|PARPORT_STATUS_SELECT))
	450	== (PARPORT_STATUS_PAPEROUT\|PARPORT_STATUS_SELECT)
	451	&& daisy < 4;
	452	++daisy) {
d32ccc43 MM	453	parport_write_data(port, daisy);
	454	udelay(2);
	455	parport_frob_control(port,
1da177e4 LT	456	PARPORT_CONTROL_STROBE,
1da177e4 LT	457	PARPORT_CONTROL_STROBE);
d32ccc43 MM	458	udelay(1);
	459	parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
	460	udelay(1);
1da177e4	461
d32ccc43	462	add_dev(numdevs++, port, daisy);
1da177e4	463
310c8c32 MK	464	/* See if this device thought it was the last in the
	465	* chain. */
	466	if (!(s & PARPORT_STATUS_BUSY))
	467	break;
1da177e4	468
310c8c32 MK	469	/* We are seeing pass through status now. We see
	470	last_dev from next device or if last_dev does not
	471	work status lines from some non-daisy chain
	472	device. */
d32ccc43	473	s = parport_read_status(port);
1da177e4 LT	474	}
1da177e4 LT	475
d32ccc43	476	parport_write_data(port, 0xff); udelay(2);
1da177e4	477	detected = numdevs - thisdev;
d32ccc43	478	DPRINTK(KERN_DEBUG "%s: Found %d daisy-chained devices\n", port->name,
1da177e4 LT	479	detected);
	480
	481	/* Ask the new devices to introduce themselves. */
d32ccc43	482	deviceid = kmalloc(1024, GFP_KERNEL);
1da177e4 LT	483	if (!deviceid) return 0;
	484
	485	for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
d32ccc43	486	parport_device_id(thisdev, deviceid, 1024);
1da177e4	487
d32ccc43	488	kfree(deviceid);
1da177e4 LT	489	return detected;
1da177e4 LT	490	}