linux-sg2042/drivers/net/irda/actisys-sir.c

247 lines
7.5 KiB
C

/*********************************************************************
*
* Filename: actisys.c
* Version: 1.1
* Description: Implementation for the ACTiSYS IR-220L and IR-220L+
* dongles
* Status: Beta.
* Authors: Dag Brattli <dagb@cs.uit.no> (initially)
* Jean Tourrilhes <jt@hpl.hp.com> (new version)
* Martin Diehl <mad@mdiehl.de> (new version for sir_dev)
* Created at: Wed Oct 21 20:02:35 1998
* Modified at: Sun Oct 27 22:02:13 2002
* Modified by: Martin Diehl <mad@mdiehl.de>
*
* Copyright (c) 1998-1999 Dag Brattli, All Rights Reserved.
* Copyright (c) 1999 Jean Tourrilhes
* Copyright (c) 2002 Martin Diehl
*
* 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.
*
* Neither Dag Brattli nor University of Tromsø admit liability nor
* provide warranty for any of this software. This material is
* provided "AS-IS" and at no charge.
*
********************************************************************/
/*
* Changelog
*
* 0.8 -> 0.9999 - Jean
* o New initialisation procedure : much safer and correct
* o New procedure the change speed : much faster and simpler
* o Other cleanups & comments
* Thanks to Lichen Wang @ Actisys for his excellent help...
*
* 1.0 -> 1.1 - Martin Diehl
* modified for new sir infrastructure
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <net/irda/irda.h>
#include "sir-dev.h"
/*
* Define the timing of the pulses we send to the dongle (to reset it, and
* to toggle speeds). Basically, the limit here is the propagation speed of
* the signals through the serial port, the dongle being much faster. Any
* serial port support 115 kb/s, so we are sure that pulses 8.5 us wide can
* go through cleanly . If you are on the wild side, you can try to lower
* this value (Actisys recommended me 2 us, and 0 us work for me on a P233!)
*/
#define MIN_DELAY 10 /* 10 us to be on the conservative side */
static int actisys_open(struct sir_dev *);
static int actisys_close(struct sir_dev *);
static int actisys_change_speed(struct sir_dev *, unsigned);
static int actisys_reset(struct sir_dev *);
/* These are the baudrates supported, in the order available */
/* Note : the 220L doesn't support 38400, but we will fix that below */
static unsigned baud_rates[] = { 9600, 19200, 57600, 115200, 38400 };
#define MAX_SPEEDS (sizeof(baud_rates)/sizeof(baud_rates[0]))
static struct dongle_driver act220l = {
.owner = THIS_MODULE,
.driver_name = "Actisys ACT-220L",
.type = IRDA_ACTISYS_DONGLE,
.open = actisys_open,
.close = actisys_close,
.reset = actisys_reset,
.set_speed = actisys_change_speed,
};
static struct dongle_driver act220l_plus = {
.owner = THIS_MODULE,
.driver_name = "Actisys ACT-220L+",
.type = IRDA_ACTISYS_PLUS_DONGLE,
.open = actisys_open,
.close = actisys_close,
.reset = actisys_reset,
.set_speed = actisys_change_speed,
};
static int __init actisys_sir_init(void)
{
int ret;
/* First, register an Actisys 220L dongle */
ret = irda_register_dongle(&act220l);
if (ret < 0)
return ret;
/* Now, register an Actisys 220L+ dongle */
ret = irda_register_dongle(&act220l_plus);
if (ret < 0) {
irda_unregister_dongle(&act220l);
return ret;
}
return 0;
}
static void __exit actisys_sir_cleanup(void)
{
/* We have to remove both dongles */
irda_unregister_dongle(&act220l_plus);
irda_unregister_dongle(&act220l);
}
static int actisys_open(struct sir_dev *dev)
{
struct qos_info *qos = &dev->qos;
sirdev_set_dtr_rts(dev, TRUE, TRUE);
/* Set the speeds we can accept */
qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
/* Remove support for 38400 if this is not a 220L+ dongle */
if (dev->dongle_drv->type == IRDA_ACTISYS_DONGLE)
qos->baud_rate.bits &= ~IR_38400;
qos->min_turn_time.bits = 0x7f; /* Needs 0.01 ms */
irda_qos_bits_to_value(qos);
/* irda thread waits 50 msec for power settling */
return 0;
}
static int actisys_close(struct sir_dev *dev)
{
/* Power off the dongle */
sirdev_set_dtr_rts(dev, FALSE, FALSE);
return 0;
}
/*
* Function actisys_change_speed (task)
*
* Change speed of the ACTiSYS IR-220L and IR-220L+ type IrDA dongles.
* To cycle through the available baud rates, pulse RTS low for a few us.
*
* First, we reset the dongle to always start from a known state.
* Then, we cycle through the speeds by pulsing RTS low and then up.
* The dongle allow us to pulse quite fast, se we can set speed in one go,
* which is must faster ( < 100 us) and less complex than what is found
* in some other dongle drivers...
* Note that even if the new speed is the same as the current speed,
* we reassert the speed. This make sure that things are all right,
* and it's fast anyway...
* By the way, this function will work for both type of dongles,
* because the additional speed is at the end of the sequence...
*/
static int actisys_change_speed(struct sir_dev *dev, unsigned speed)
{
int ret = 0;
int i = 0;
IRDA_DEBUG(4, "%s(), speed=%d (was %d)\n", __FUNCTION__,
speed, dev->speed);
/* dongle was already resetted from irda_request state machine,
* we are in known state (dongle default)
*/
/*
* Now, we can set the speed requested. Send RTS pulses until we
* reach the target speed
*/
for (i = 0; i < MAX_SPEEDS; i++) {
if (speed == baud_rates[i]) {
dev->speed = speed;
break;
}
/* Set RTS low for 10 us */
sirdev_set_dtr_rts(dev, TRUE, FALSE);
udelay(MIN_DELAY);
/* Set RTS high for 10 us */
sirdev_set_dtr_rts(dev, TRUE, TRUE);
udelay(MIN_DELAY);
}
/* Check if life is sweet... */
if (i >= MAX_SPEEDS) {
actisys_reset(dev);
ret = -EINVAL; /* This should not happen */
}
/* Basta lavoro, on se casse d'ici... */
return ret;
}
/*
* Function actisys_reset (task)
*
* Reset the Actisys type dongle. Warning, this function must only be
* called with a process context!
*
* We need to do two things in this function :
* o first make sure that the dongle is in a state where it can operate
* o second put the dongle in a know state
*
* The dongle is powered of the RTS and DTR lines. In the dongle, there
* is a big capacitor to accommodate the current spikes. This capacitor
* takes a least 50 ms to be charged. In theory, the Bios set those lines
* up, so by the time we arrive here we should be set. It doesn't hurt
* to be on the conservative side, so we will wait...
* <Martin : move above comment to irda_config_fsm>
* Then, we set the speed to 9600 b/s to get in a known state (see in
* change_speed for details). It is needed because the IrDA stack
* has tried to set the speed immediately after our first return,
* so before we can be sure the dongle is up and running.
*/
static int actisys_reset(struct sir_dev *dev)
{
/* Reset the dongle : set DTR low for 10 us */
sirdev_set_dtr_rts(dev, FALSE, TRUE);
udelay(MIN_DELAY);
/* Go back to normal mode */
sirdev_set_dtr_rts(dev, TRUE, TRUE);
dev->speed = 9600; /* That's the default */
return 0;
}
MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no> - Jean Tourrilhes <jt@hpl.hp.com>");
MODULE_DESCRIPTION("ACTiSYS IR-220L and IR-220L+ dongle driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("irda-dongle-2"); /* IRDA_ACTISYS_DONGLE */
MODULE_ALIAS("irda-dongle-3"); /* IRDA_ACTISYS_PLUS_DONGLE */
module_init(actisys_sir_init);
module_exit(actisys_sir_cleanup);