/* ++++++++++
FILE: digital.c
REVS: $Revision: 1.14 $
NAME: herold
DATE: Tue Jan 23 13:09:56 PST 1996
Copyright (c) 1996-97 by Be Incorporated. All Rights Reserved.
Driver for the digital i/o portion of the geek port.
+++++ */
#include
#include
#include
#include
#include
#include
#ifndef DEBUG
#define DEBUG 0
#endif
#if DEBUG
#define ddprintf dprintf
#else
#define ddprintf
#endif
/* -----
private definitions and types
----- */
#define PORT_A_MASK 0x01
#define PORT_B_MASK 0x02
/* -----
private globals
----- */
static int open_count[2] = {0,0}; /* # outstanding opens to each port */
static spinlock port_locks[2] = {0,0}; /* locks for port access */
static vshort *output_enable; /* -> output enable reg */
static vchar *port_addr[2]; /* -> ports */
/* ----------
find_digport - determines if digital port hardware is present, and
set up globals to point to it.
----- */
bool
find_digport (void)
{
area_info a;
area_id id;
if (io_card_version() < 0)
return FALSE;
id = find_area ("isa_io");
if (id < 0)
return FALSE;
if (get_area_info (id, &a) < 0)
return FALSE;
output_enable = (vshort *) ((char *)a.address + GEEK_OUTPUT_ENABLE);
port_addr[0] = (vchar *)a.address + GEEK_DIGITAL_PORT_A;
port_addr[1] = (vchar *)a.address + GEEK_DIGITAL_PORT_B;
return TRUE;
}
/* ----------
lock_port - gains exclusive access to hw, driver resources
----- */
static cpu_status
lock_port (int id)
{
cpu_status ps;
ps = disable_interrupts();
acquire_spinlock (port_locks + id);
return ps;
}
/* ----------
unlock_port - relinquish exclusive access to hw, driver resources
----- */
static void
unlock_port (int id, cpu_status ps)
{
release_spinlock (port_locks + id);
restore_interrupts(ps);
}
/* ----------
set_digital_port_direction
assumes port is locked, or does not have to be.
----- */
static void
set_digital_port_direction (int id, int direction)
{
short oe;
static char masks[2] = {PORT_A_MASK, PORT_B_MASK};
oe = B_LENDIAN_TO_HOST_INT16 (*output_enable);
__eieio();
if (direction == DIGITAL_PORT_INPUT)
*output_enable = B_HOST_TO_LENDIAN_INT16 (oe & ~masks[id]);
else
*output_enable = B_HOST_TO_LENDIAN_INT16 (oe | masks[id]);
__eieio();
}
/* ----------
init_hardware - looks for geekport, sets digital ports to inputs
----- */
status_t
init_hardware (void)
{
if (!find_digport())
return B_ERROR;
set_digital_port_direction (0, DIGITAL_PORT_INPUT);
set_digital_port_direction (1, DIGITAL_PORT_INPUT);
return B_NO_ERROR;
}
/* ----------
init_driver - set up driver globals
----- */
status_t
init_driver (void)
{
return find_digport() ? B_NO_ERROR : B_ERROR;
}
/* ----------
digital_port_open - set up digital ports
----- */
static status_t
digital_port_open (const char *name, uint32 flags, void **cookie)
{
int id;
cpu_status ps;
/* distinguish open of port a from port b */
ddprintf("opening '%s'\n", name);
id = (name [strlen(name)-1] == 'a') ? 0 : 1;
ps = lock_port (id);
open_count [id] += 1; /* count opens on this port */
unlock_port (id, ps);
*cookie = (void *)id; /* remember which port this is */
return B_NO_ERROR;
}
/* ----------
digital_port_close
----- */
static status_t
digital_port_close (void *cookie)
{
cpu_status ps;
int id;
id = (int) cookie;
if (id < 0 || id > 1) /* sanity check */
return B_ERROR;
ps = lock_port (id);
open_count[id] -= 1;
if (open_count[id] == 0)
set_digital_port_direction (id, DIGITAL_PORT_INPUT);
unlock_port (id, ps);
return B_NO_ERROR;
}
/* ----------
digital_port_read
----- */
static status_t
digital_port_read (void *cookie, off_t pos, void *buf, size_t *nbytes)
{
int id;
id = (int) cookie;
if (id < 0 || id > 1) /* sanity check */
return B_ERROR;
*(char *)buf = *port_addr[id];
return B_NO_ERROR;
}
/* ----------
digital_port_write
----- */
static status_t
digital_port_write (void *cookie, off_t pos, const void *buf, size_t *nbytes)
{
int id;
id = (int) cookie;
if (id < 0 || id > 1) /* sanity check */
return B_ERROR;
*port_addr[id] = *(char *)buf;
return B_NO_ERROR;
}
/* ----------
digital_port_control
----- */
static status_t
digital_port_control (void *cookie, uint32 op, void *arg, size_t len)
{
int id;
int dir;
cpu_status ps;
id = (int) cookie;
if (id < 0 || id > 1) /* sanity check */
return B_ERROR;
switch (op) {
case SET_DIGITAL_PORT_DIRECTION:
dir = (int)arg;
if (dir != DIGITAL_PORT_INPUT && dir != DIGITAL_PORT_OUTPUT)
return B_ERROR;
ps = lock_port (id);
set_digital_port_direction (id, dir);
unlock_port (id, ps);
return B_NO_ERROR;
}
return B_ERROR;
}
/* -----------
digital_port_free
----------- */
static status_t
digital_port_free (void *cookie)
{
return B_NO_ERROR;
}
/* -----
public globals and functions
----- */
static const char *digital_name[] = {
"beboxhw/geekport/digital/digital_port_a",
"beboxhw/geekport/digital/digital_port_b",
NULL
};
device_hooks digital_port_devices = {
digital_port_open, /* -> open entry point */
digital_port_close, /* -> close entry point */
digital_port_free, /* -> free cookies allocated */
digital_port_control, /* -> control entry point */
digital_port_read, /* -> read entry point */
digital_port_write /* -> write entry point */
};
const char **
publish_devices()
{
return digital_name;
}
device_hooks *
find_device(const char *name)
{
return &digital_port_devices;
}
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