[linux-2.6-block.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/slab.h>
#include <linux/sched/signal.h>

#include <asm/current.h>
#include <linux/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;

/* 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
 *
 *	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)
{
	struct daisydev *p = topology;
	struct pardev_cb par_cb;
	struct parport *port;
	struct pardevice *dev;
	int daisy;

	memset(&par_cb, 0, sizeof(par_cb));
	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_dev_model(port, name, &par_cb, devnum);
	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;
}

static int daisy_drv_probe(struct pardevice *par_dev)
{
	struct device_driver *drv = par_dev->dev.driver;

	if (strcmp(drv->name, "daisy_drv"))
		return -ENODEV;
	if (strcmp(par_dev->name, daisy_dev_name))
		return -ENODEV;

	return 0;
}

static struct parport_driver daisy_driver = {
	.name = "daisy_drv",
	.probe = daisy_drv_probe,
	.devmodel = true,
};

int daisy_drv_init(void)
{
	return parport_register_driver(&daisy_driver);
}

void daisy_drv_exit(void)
{
	parport_unregister_driver(&daisy_driver);
}
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>
5a0e3ad6	25	#include <linux/slab.h>
174cd4b1	26	#include <linux/sched/signal.h>
1da177e4 LT	27
1da177e4 LT	28	#include <asm/current.h>
7c0f6ba6	29	#include <linux/uaccess.h>
1da177e4 LT	30
	31	#undef DEBUG
	32
	33	#ifdef DEBUG
d32ccc43	34	#define DPRINTK(stuff...) printk(stuff)
1da177e4 LT	35	#else
	36	#define DPRINTK(stuff...)
	37	#endif
	38
	39	static struct daisydev {
	40	struct daisydev *next;
	41	struct parport *port;
	42	int daisy;
	43	int devnum;
	44	} *topology = NULL;
	45	static DEFINE_SPINLOCK(topology_lock);
	46
df4c756e	47	static int numdevs;
1da177e4 LT	48
1da177e4 LT	49	/* Forward-declaration of lower-level functions. */
d32ccc43 MM	50	static int mux_present(struct parport *port);
	51	static int num_mux_ports(struct parport *port);
	52	static int select_port(struct parport *port);
	53	static int assign_addrs(struct parport *port);
1da177e4 LT	54
1da177e4 LT	55	/* Add a device to the discovered topology. */
d32ccc43	56	static void add_dev(int devnum, struct parport *port, int daisy)
1da177e4 LT	57	{
1da177e4 LT	58	struct daisydev newdev, *p;
d32ccc43	59	newdev = kmalloc(sizeof(struct daisydev), GFP_KERNEL);
1da177e4 LT	60	if (newdev) {
	61	newdev->port = port;
	62	newdev->daisy = daisy;
	63	newdev->devnum = devnum;
	64	spin_lock(&topology_lock);
	65	for (p = &topology; p && (p)->devnum<devnum; p = &(*p)->next)
	66	;
	67	newdev->next = *p;
	68	*p = newdev;
	69	spin_unlock(&topology_lock);
	70	}
	71	}
	72
	73	/* Clone a parport (actually, make an alias). */
d32ccc43	74	static struct parport clone_parport(struct parport real, int muxport)
1da177e4	75	{
d32ccc43	76	struct parport *extra = parport_register_port(real->base,
1da177e4 LT	77	real->irq,
	78	real->dma,
	79	real->ops);
	80	if (extra) {
	81	extra->portnum = real->portnum;
	82	extra->physport = real;
	83	extra->muxport = muxport;
	84	real->slaves[muxport-1] = extra;
	85	}
	86
	87	return extra;
	88	}
	89
	90	/* Discover the IEEE1284.3 topology on a port -- muxes and daisy chains.
	91	* Return value is number of devices actually detected. */
d32ccc43	92	int parport_daisy_init(struct parport *port)
1da177e4 LT	93	{
	94	int detected = 0;
	95	char *deviceid;
	96	static const char th[] = { /0*/"th", "st", "nd", "rd", "th" };
	97	int num_ports;
	98	int i;
	99	int last_try = 0;
	100
	101	again:
	102	/* Because this is called before any other devices exist,
	103	* we don't have to claim exclusive access. */
	104
	105	/* If mux present on normal port, need to create new
	106	* parports for each extra port. */
d32ccc43	107	if (port->muxport < 0 && mux_present(port) &&
1da177e4	108	/* don't be fooled: a mux must have 2 or 4 ports. */
d32ccc43	109	((num_ports = num_mux_ports(port)) == 2 \|\| num_ports == 4)) {
1da177e4 LT	110	/* Leave original as port zero. */
1da177e4 LT	111	port->muxport = 0;
d32ccc43	112	printk(KERN_INFO
1da177e4 LT	113	"%s: 1st (default) port of %d-way multiplexor\n",
	114	port->name, num_ports);
	115	for (i = 1; i < num_ports; i++) {
	116	/* Clone the port. */
d32ccc43	117	struct parport *extra = clone_parport(port, i);
1da177e4	118	if (!extra) {
d32ccc43	119	if (signal_pending(current))
1da177e4 LT	120	break;
1da177e4 LT	121
d32ccc43	122	schedule();
1da177e4 LT	123	continue;
	124	}
	125
d32ccc43	126	printk(KERN_INFO
1da177e4 LT	127	"%s: %d%s port of %d-way multiplexor on %s\n",
	128	extra->name, i + 1, th[i + 1], num_ports,
	129	port->name);
	130
	131	/* Analyse that port too. We won't recurse
	132	forever because of the 'port->muxport < 0'
	133	test above. */
	134	parport_daisy_init(extra);
	135	}
	136	}
	137
	138	if (port->muxport >= 0)
d32ccc43	139	select_port(port);
1da177e4	140
d32ccc43 MM	141	parport_daisy_deselect_all(port);
d32ccc43 MM	142	detected += assign_addrs(port);
1da177e4 LT	143
1da177e4 LT	144	/* Count the potential legacy device at the end. */
d32ccc43	145	add_dev(numdevs++, port, -1);
1da177e4 LT	146
1da177e4 LT	147	/* Find out the legacy device's IEEE 1284 device ID. */
d32ccc43	148	deviceid = kmalloc(1024, GFP_KERNEL);
1da177e4	149	if (deviceid) {
d32ccc43	150	if (parport_device_id(numdevs - 1, deviceid, 1024) > 2)
1da177e4 LT	151	detected++;
1da177e4 LT	152
d32ccc43	153	kfree(deviceid);
1da177e4 LT	154	}
	155
	156	if (!detected && !last_try) {
	157	/* No devices were detected. Perhaps they are in some
	158	funny state; let's try to reset them and see if
	159	they wake up. */
d32ccc43 MM	160	parport_daisy_fini(port);
	161	parport_write_control(port, PARPORT_CONTROL_SELECT);
	162	udelay(50);
	163	parport_write_control(port,
1da177e4 LT	164	PARPORT_CONTROL_SELECT \|
1da177e4 LT	165	PARPORT_CONTROL_INIT);
d32ccc43	166	udelay(50);
1da177e4 LT	167	last_try = 1;
	168	goto again;
	169	}
	170
	171	return detected;
	172	}
	173
	174	/* Forget about devices on a physical port. */
d32ccc43	175	void parport_daisy_fini(struct parport *port)
1da177e4 LT	176	{
	177	struct daisydev **p;
	178
	179	spin_lock(&topology_lock);
	180	p = &topology;
	181	while (*p) {
	182	struct daisydev dev = p;
	183	if (dev->port != port) {
	184	p = &dev->next;
	185	continue;
	186	}
	187	*p = dev->next;
	188	kfree(dev);
	189	}
	190
	191	/* Gaps in the numbering could be handled better. How should
	192	someone enumerate through all IEEE1284.3 devices in the
	193	topology?. */
	194	if (!topology) numdevs = 0;
	195	spin_unlock(&topology_lock);
	196	return;
	197	}
	198
	199	/**
	200	* parport_open - find a device by canonical device number
	201	* @devnum: canonical device number
	202	* @name: name to associate with the device
1da177e4 LT	203	*
	204	* This function is similar to parport_register_device(), except
	205	* that it locates a device by its number rather than by the port
	206	* it is attached to.
	207	*
	208	* All parameters except for @devnum are the same as for
	209	* parport_register_device(). The return value is the same as
	210	* for parport_register_device().
	211	**/
	212
5712cb3d	213	struct pardevice parport_open(int devnum, const char name)
1da177e4 LT	214	{
1da177e4 LT	215	struct daisydev *p = topology;
1aec4211	216	struct pardev_cb par_cb;
1da177e4 LT	217	struct parport *port;
	218	struct pardevice *dev;
	219	int daisy;
	220
1aec4211	221	memset(&par_cb, 0, sizeof(par_cb));
1da177e4 LT	222	spin_lock(&topology_lock);
	223	while (p && p->devnum != devnum)
	224	p = p->next;
	225
	226	if (!p) {
	227	spin_unlock(&topology_lock);
	228	return NULL;
	229	}
	230
	231	daisy = p->daisy;
	232	port = parport_get_port(p->port);
	233	spin_unlock(&topology_lock);
	234
1aec4211	235	dev = parport_register_dev_model(port, name, &par_cb, devnum);
1da177e4 LT	236	parport_put_port(port);
	237	if (!dev)
	238	return NULL;
	239
	240	dev->daisy = daisy;
	241
	242	/* Check that there really is a device to select. */
	243	if (daisy >= 0) {
	244	int selected;
d32ccc43	245	parport_claim_or_block(dev);
1da177e4	246	selected = port->daisy;
d32ccc43	247	parport_release(dev);
1da177e4	248
c29a75ed	249	if (selected != daisy) {
1da177e4	250	/* No corresponding device. */
d32ccc43	251	parport_unregister_device(dev);
1da177e4 LT	252	return NULL;
	253	}
	254	}
	255
	256	return dev;
	257	}
	258
	259	/**
	260	* parport_close - close a device opened with parport_open()
	261	* @dev: device to close
	262	*
	263	* This is to parport_open() as parport_unregister_device() is to
	264	* parport_register_device().
	265	**/
	266
d32ccc43	267	void parport_close(struct pardevice *dev)
1da177e4	268	{
d32ccc43	269	parport_unregister_device(dev);
1da177e4 LT	270	}
1da177e4 LT	271
1da177e4	272	/* Send a daisy-chain-style CPP command packet. */
d32ccc43	273	static int cpp_daisy(struct parport *port, int cmd)
1da177e4 LT	274	{
	275	unsigned char s;
	276
d32ccc43 MM	277	parport_data_forward(port);
	278	parport_write_data(port, 0xaa); udelay(2);
	279	parport_write_data(port, 0x55); udelay(2);
	280	parport_write_data(port, 0x00); udelay(2);
	281	parport_write_data(port, 0xff); udelay(2);
	282	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	283	\| PARPORT_STATUS_PAPEROUT
	284	\| PARPORT_STATUS_SELECT
	285	\| PARPORT_STATUS_ERROR);
	286	if (s != (PARPORT_STATUS_BUSY
	287	\| PARPORT_STATUS_PAPEROUT
	288	\| PARPORT_STATUS_SELECT
	289	\| PARPORT_STATUS_ERROR)) {
d32ccc43	290	DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff(%02x)\n",
1da177e4 LT	291	port->name, s);
	292	return -ENXIO;
	293	}
	294
d32ccc43 MM	295	parport_write_data(port, 0x87); udelay(2);
d32ccc43 MM	296	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	297	\| PARPORT_STATUS_PAPEROUT
	298	\| PARPORT_STATUS_SELECT
	299	\| PARPORT_STATUS_ERROR);
	300	if (s != (PARPORT_STATUS_SELECT \| PARPORT_STATUS_ERROR)) {
d32ccc43	301	DPRINTK(KERN_DEBUG "%s: cpp_daisy: aa5500ff87(%02x)\n",
1da177e4 LT	302	port->name, s);
	303	return -ENXIO;
	304	}
	305
d32ccc43 MM	306	parport_write_data(port, 0x78); udelay(2);
	307	parport_write_data(port, cmd); udelay(2);
	308	parport_frob_control(port,
1da177e4 LT	309	PARPORT_CONTROL_STROBE,
1da177e4 LT	310	PARPORT_CONTROL_STROBE);
d32ccc43 MM	311	udelay(1);
	312	s = parport_read_status(port);
	313	parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
	314	udelay(1);
	315	parport_write_data(port, 0xff); udelay(2);
1da177e4 LT	316
	317	return s;
	318	}
	319
	320	/* Send a mux-style CPP command packet. */
d32ccc43	321	static int cpp_mux(struct parport *port, int cmd)
1da177e4 LT	322	{
	323	unsigned char s;
	324	int rc;
	325
d32ccc43 MM	326	parport_data_forward(port);
	327	parport_write_data(port, 0xaa); udelay(2);
	328	parport_write_data(port, 0x55); udelay(2);
	329	parport_write_data(port, 0xf0); udelay(2);
	330	parport_write_data(port, 0x0f); udelay(2);
	331	parport_write_data(port, 0x52); udelay(2);
	332	parport_write_data(port, 0xad); udelay(2);
	333	parport_write_data(port, cmd); udelay(2);
1da177e4	334
d32ccc43	335	s = parport_read_status(port);
1da177e4	336	if (!(s & PARPORT_STATUS_ACK)) {
d32ccc43	337	DPRINTK(KERN_DEBUG "%s: cpp_mux: aa55f00f52ad%02x(%02x)\n",
1da177e4 LT	338	port->name, cmd, s);
	339	return -EIO;
	340	}
	341
	342	rc = (((s & PARPORT_STATUS_SELECT ? 1 : 0) << 0) \|
	343	((s & PARPORT_STATUS_PAPEROUT ? 1 : 0) << 1) \|
	344	((s & PARPORT_STATUS_BUSY ? 0 : 1) << 2) \|
	345	((s & PARPORT_STATUS_ERROR ? 0 : 1) << 3));
	346
	347	return rc;
	348	}
	349
d32ccc43	350	void parport_daisy_deselect_all(struct parport *port)
1da177e4	351	{
d32ccc43	352	cpp_daisy(port, 0x30);
1da177e4 LT	353	}
1da177e4 LT	354
d32ccc43	355	int parport_daisy_select(struct parport *port, int daisy, int mode)
1da177e4 LT	356	{
	357	switch (mode)
	358	{
	359	// For these modes we should switch to EPP mode:
	360	case IEEE1284_MODE_EPP:
	361	case IEEE1284_MODE_EPPSL:
	362	case IEEE1284_MODE_EPPSWE:
d32ccc43	363	return !(cpp_daisy(port, 0x20 + daisy) &
7c9cc3be	364	PARPORT_STATUS_ERROR);
1da177e4 LT	365
	366	// For these modes we should switch to ECP mode:
	367	case IEEE1284_MODE_ECP:
	368	case IEEE1284_MODE_ECPRLE:
	369	case IEEE1284_MODE_ECPSWE:
d32ccc43	370	return !(cpp_daisy(port, 0xd0 + daisy) &
7c9cc3be	371	PARPORT_STATUS_ERROR);
1da177e4 LT	372
	373	// Nothing was told for BECP in Daisy chain specification.
	374	// May be it's wise to use ECP?
	375	case IEEE1284_MODE_BECP:
	376	// Others use compat mode
	377	case IEEE1284_MODE_NIBBLE:
	378	case IEEE1284_MODE_BYTE:
	379	case IEEE1284_MODE_COMPAT:
	380	default:
d32ccc43	381	return !(cpp_daisy(port, 0xe0 + daisy) &
7c9cc3be	382	PARPORT_STATUS_ERROR);
1da177e4 LT	383	}
	384	}
	385
d32ccc43	386	static int mux_present(struct parport *port)
1da177e4	387	{
d32ccc43	388	return cpp_mux(port, 0x51) == 3;
1da177e4 LT	389	}
1da177e4 LT	390
d32ccc43	391	static int num_mux_ports(struct parport *port)
1da177e4	392	{
d32ccc43	393	return cpp_mux(port, 0x58);
1da177e4 LT	394	}
1da177e4 LT	395
d32ccc43	396	static int select_port(struct parport *port)
1da177e4 LT	397	{
1da177e4 LT	398	int muxport = port->muxport;
d32ccc43	399	return cpp_mux(port, 0x60 + muxport) == muxport;
1da177e4 LT	400	}
1da177e4 LT	401
d32ccc43	402	static int assign_addrs(struct parport *port)
1da177e4	403	{
310c8c32	404	unsigned char s;
1da177e4 LT	405	unsigned char daisy;
	406	int thisdev = numdevs;
	407	int detected;
	408	char *deviceid;
	409
d32ccc43 MM	410	parport_data_forward(port);
	411	parport_write_data(port, 0xaa); udelay(2);
	412	parport_write_data(port, 0x55); udelay(2);
	413	parport_write_data(port, 0x00); udelay(2);
	414	parport_write_data(port, 0xff); udelay(2);
	415	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	416	\| PARPORT_STATUS_PAPEROUT
	417	\| PARPORT_STATUS_SELECT
	418	\| PARPORT_STATUS_ERROR);
	419	if (s != (PARPORT_STATUS_BUSY
	420	\| PARPORT_STATUS_PAPEROUT
	421	\| PARPORT_STATUS_SELECT
	422	\| PARPORT_STATUS_ERROR)) {
d32ccc43	423	DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff(%02x)\n",
1da177e4 LT	424	port->name, s);
	425	return 0;
	426	}
	427
d32ccc43 MM	428	parport_write_data(port, 0x87); udelay(2);
d32ccc43 MM	429	s = parport_read_status(port) & (PARPORT_STATUS_BUSY
1da177e4 LT	430	\| PARPORT_STATUS_PAPEROUT
	431	\| PARPORT_STATUS_SELECT
	432	\| PARPORT_STATUS_ERROR);
	433	if (s != (PARPORT_STATUS_SELECT \| PARPORT_STATUS_ERROR)) {
d32ccc43	434	DPRINTK(KERN_DEBUG "%s: assign_addrs: aa5500ff87(%02x)\n",
1da177e4 LT	435	port->name, s);
	436	return 0;
	437	}
	438
d32ccc43 MM	439	parport_write_data(port, 0x78); udelay(2);
d32ccc43 MM	440	s = parport_read_status(port);
1da177e4	441
310c8c32 MK	442	for (daisy = 0;
	443	(s & (PARPORT_STATUS_PAPEROUT\|PARPORT_STATUS_SELECT))
	444	== (PARPORT_STATUS_PAPEROUT\|PARPORT_STATUS_SELECT)
	445	&& daisy < 4;
	446	++daisy) {
d32ccc43 MM	447	parport_write_data(port, daisy);
	448	udelay(2);
	449	parport_frob_control(port,
1da177e4 LT	450	PARPORT_CONTROL_STROBE,
1da177e4 LT	451	PARPORT_CONTROL_STROBE);
d32ccc43 MM	452	udelay(1);
	453	parport_frob_control(port, PARPORT_CONTROL_STROBE, 0);
	454	udelay(1);
1da177e4	455
d32ccc43	456	add_dev(numdevs++, port, daisy);
1da177e4	457
310c8c32 MK	458	/* See if this device thought it was the last in the
	459	* chain. */
	460	if (!(s & PARPORT_STATUS_BUSY))
	461	break;
1da177e4	462
310c8c32 MK	463	/* We are seeing pass through status now. We see
	464	last_dev from next device or if last_dev does not
	465	work status lines from some non-daisy chain
	466	device. */
d32ccc43	467	s = parport_read_status(port);
1da177e4 LT	468	}
1da177e4 LT	469
d32ccc43	470	parport_write_data(port, 0xff); udelay(2);
1da177e4	471	detected = numdevs - thisdev;
d32ccc43	472	DPRINTK(KERN_DEBUG "%s: Found %d daisy-chained devices\n", port->name,
1da177e4 LT	473	detected);
	474
	475	/* Ask the new devices to introduce themselves. */
d32ccc43	476	deviceid = kmalloc(1024, GFP_KERNEL);
1da177e4 LT	477	if (!deviceid) return 0;
	478
	479	for (daisy = 0; thisdev < numdevs; thisdev++, daisy++)
d32ccc43	480	parport_device_id(thisdev, deviceid, 1024);
1da177e4	481
d32ccc43	482	kfree(deviceid);
1da177e4 LT	483	return detected;
1da177e4 LT	484	}
1aec4211 SM	485
	486	static int daisy_drv_probe(struct pardevice *par_dev)
	487	{
	488	struct device_driver *drv = par_dev->dev.driver;
	489
	490	if (strcmp(drv->name, "daisy_drv"))
	491	return -ENODEV;
	492	if (strcmp(par_dev->name, daisy_dev_name))
	493	return -ENODEV;
	494
	495	return 0;
	496	}
	497
	498	static struct parport_driver daisy_driver = {
	499	.name = "daisy_drv",
	500	.probe = daisy_drv_probe,
	501	.devmodel = true,
	502	};
	503
	504	int daisy_drv_init(void)
	505	{
	506	return parport_register_driver(&daisy_driver);
	507	}
	508
	509	void daisy_drv_exit(void)
	510	{
	511	parport_unregister_driver(&daisy_driver);
	512	}