482 lines
12 KiB
C
482 lines
12 KiB
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.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
|
|
*
|
|
* 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 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, NULL, NULL, NULL, 0, NULL);
|
|
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;
|
|
}
|