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/*********************************************************************
*
* Filename: actisys.c
* Version: 1.0
* 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)
* Created at: Wed Oct 21 20:02:35 1998
* Modified at: Fri Dec 17 09:10:43 1999
* Modified by: Dag Brattli <dagb@cs.uit.no>
*
* Copyright (c) 1998-1999 Dag Brattli, All Rights Reserved.
* Copyright (c) 1999 Jean Tourrilhes
*
* 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 Tromsų 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...
*/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/tty.h>
#include <linux/sched.h>
#include <linux/init.h>
#include <net/irda/irda.h>
#include <net/irda/irmod.h>
#include <net/irda/irda_device.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_change_speed(struct irda_task *task);
static int actisys_reset(struct irda_task *task);
static void actisys_open(dongle_t *self, struct qos_info *qos);
static void actisys_close(dongle_t *self);
/* These are the baudrates supported, in the order available */
/* Note : the 220L doesn't support 38400, but we will fix that below */
static __u32 baud_rates[] = { 9600, 19200, 57600, 115200, 38400 };
#define MAX_SPEEDS 5
static struct dongle_reg dongle = {
Q_NULL,
IRDA_ACTISYS_DONGLE,
actisys_open,
actisys_close,
actisys_reset,
actisys_change_speed,
};
static struct dongle_reg dongle_plus = {
Q_NULL,
IRDA_ACTISYS_PLUS_DONGLE,
actisys_open,
actisys_close,
actisys_reset,
actisys_change_speed,
};
/*
* Function actisys_change_speed (task)
*
* There is two model of Actisys dongle we are dealing with,
* the 220L and 220L+. At this point, only irattach knows with
* kind the user has requested (it was an argument on irattach
* command line).
* So, we register a dongle of each sort and let irattach
* pick the right one...
*/
int __init actisys_init(void)
{
int ret;
/* First, register an Actisys 220L dongle */
ret = irda_device_register_dongle(&dongle);
if (ret < 0)
return ret;
/* Now, register an Actisys 220L+ dongle */
ret = irda_device_register_dongle(&dongle_plus);
if (ret < 0) {
irda_device_unregister_dongle(&dongle);
return ret;
}
return 0;
}
void actisys_cleanup(void)
{
/* We have to remove both dongles */
irda_device_unregister_dongle(&dongle);
irda_device_unregister_dongle(&dongle_plus);
}
static void actisys_open(dongle_t *self, struct qos_info *qos)
{
/* Power on the dongle */
self->set_dtr_rts(self->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 (self->issue->type == IRDA_ACTISYS_DONGLE)
qos->baud_rate.bits &= ~IR_38400;
qos->min_turn_time.bits = 0x7f; /* Needs 0.01 ms */
MOD_INC_USE_COUNT;
}
static void actisys_close(dongle_t *self)
{
/* Power off the dongle */
self->set_dtr_rts(self->dev, FALSE, FALSE);
MOD_DEC_USE_COUNT;
}
/*
* 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 irda_task *task)
{
dongle_t *self = (dongle_t *) task->instance;
__u32 speed = (__u32) task->param; /* Target speed */
int ret = 0;
int i = 0;
IRDA_DEBUG(4, __FUNCTION__ "(), speed=%d (was %d)\n", speed,
self->speed);
/* Go to a known state by reseting the dongle */
/* Reset the dongle : set DTR low for 10 us */
self->set_dtr_rts(self->dev, FALSE, TRUE);
udelay(MIN_DELAY);
/* Go back to normal mode (we are now at 9600 b/s) */
self->set_dtr_rts(self->dev, TRUE, TRUE);
/*
* 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]) {
self->speed = baud_rates[i];
break;
}
/* Make sure previous pulse is finished */
udelay(MIN_DELAY);
/* Set RTS low for 10 us */
self->set_dtr_rts(self->dev, TRUE, FALSE);
udelay(MIN_DELAY);
/* Set RTS high for 10 us */
self->set_dtr_rts(self->dev, TRUE, TRUE);
}
/* Check if life is sweet... */
if (i >= MAX_SPEEDS)
ret = -1; /* This should not happen */
/* Basta lavoro, on se casse d'ici... */
irda_task_next_state(task, IRDA_TASK_DONE);
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 accomodate 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...
* 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 irda_task *task)
{
dongle_t *self = (dongle_t *) task->instance;
int ret = 0;
ASSERT(task != NULL, return -1;);
self->reset_task = task;
switch (task->state) {
case IRDA_TASK_INIT:
/* Set both DTR & RTS to power up the dongle */
/* In theory redundant with power up in actisys_open() */
self->set_dtr_rts(self->dev, TRUE, TRUE);
/* Sleep 50 ms to make sure capacitor is charged */
ret = MSECS_TO_JIFFIES(50);
irda_task_next_state(task, IRDA_TASK_WAIT);
break;
case IRDA_TASK_WAIT:
/* Reset the dongle : set DTR low for 10 us */
self->set_dtr_rts(self->dev, FALSE, TRUE);
udelay(MIN_DELAY);
/* Go back to normal mode */
self->set_dtr_rts(self->dev, TRUE, TRUE);
irda_task_next_state(task, IRDA_TASK_DONE);
self->reset_task = NULL;
self->speed = 9600; /* That's the default */
break;
default:
ERROR(__FUNCTION__ "(), unknown state %d\n", task->state);
irda_task_next_state(task, IRDA_TASK_DONE);
self->reset_task = NULL;
ret = -1;
break;
}
return ret;
}
#ifdef MODULE
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");
/*
* Function init_module (void)
*
* Initialize Actisys module
*
*/
int init_module(void)
{
return actisys_init();
}
/*
* Function cleanup_module (void)
*
* Cleanup Actisys module
*
*/
void cleanup_module(void)
{
actisys_cleanup();
}
#endif /* MODULE */
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