/*********************************************************************
*
*
* Filename: mcp2120.c
* Version: 1.0
* Description: Implementation for the MCP2120 (Microchip)
* Status: Experimental.
* Author: Felix Tang (tangf@eyetap.org)
* Created at: Sun Mar 31 19:32:12 EST 2002
* Based on code by: Dag Brattli <dagb@cs.uit.no>
*
* Copyright (c) 2002 Felix Tang, All Rights Reserved.
*
* 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.
*
********************************************************************/
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/init.h>
#include <net/irda/irda.h>
#include "sir-dev.h"
static int mcp2120_reset(struct sir_dev *dev);
static int mcp2120_open(struct sir_dev *dev);
static int mcp2120_close(struct sir_dev *dev);
static int mcp2120_change_speed(struct sir_dev *dev, unsigned speed);
#define MCP2120_9600 0x87
#define MCP2120_19200 0x8B
#define MCP2120_38400 0x85
#define MCP2120_57600 0x83
#define MCP2120_115200 0x81
#define MCP2120_COMMIT 0x11
static struct dongle_driver mcp2120 = {
.owner = THIS_MODULE,
.driver_name = "Microchip MCP2120",
.type = IRDA_MCP2120_DONGLE,
.open = mcp2120_open,
.close = mcp2120_close,
.reset = mcp2120_reset,
.set_speed = mcp2120_change_speed,
};
static int __init mcp2120_sir_init(void)
{
return irda_register_dongle(&mcp2120);
}
static void __exit mcp2120_sir_cleanup(void)
{
irda_unregister_dongle(&mcp2120);
}
static int mcp2120_open(struct sir_dev *dev)
{
struct qos_info *qos = &dev->qos;
IRDA_DEBUG(2, "%s()\n", __func__);
/* seems no explicit power-on required here and reset switching it on anyway */
qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
qos->min_turn_time.bits = 0x01;
irda_qos_bits_to_value(qos);
return 0;
}
static int mcp2120_close(struct sir_dev *dev)
{
IRDA_DEBUG(2, "%s()\n", __func__);
/* Power off dongle */
/* reset and inhibit mcp2120 */
sirdev_set_dtr_rts(dev, TRUE, TRUE);
// sirdev_set_dtr_rts(dev, FALSE, FALSE);
return 0;
}
/*
* Function mcp2120_change_speed (dev, speed)
*
* Set the speed for the MCP2120.
*
*/
#define MCP2120_STATE_WAIT_SPEED (SIRDEV_STATE_DONGLE_SPEED+1)
static int mcp2120_change_speed(struct sir_dev *dev, unsigned speed)
{
unsigned state = dev->fsm.substate;
unsigned delay = 0;
u8 control[2];
static int ret = 0;
IRDA_DEBUG(2, "%s()\n", __func__);
switch (state) {
case SIRDEV_STATE_DONGLE_SPEED:
/* Set DTR to enter command mode */
sirdev_set_dtr_rts(dev, TRUE, FALSE);
udelay(500);
ret = 0;
switch (speed) {
default:
speed = 9600;
ret = -EINVAL;
/* fall through */
case 9600:
control[0] = MCP2120_9600;
//printk("mcp2120 9600\n");
break;
case 19200:
control[0] = MCP2120_19200;
//printk("mcp2120 19200\n");
break;
case 34800:
control[0] = MCP2120_38400;
//printk("mcp2120 38400\n");
break;
case 57600:
control[0] = MCP2120_57600;
//printk("mcp2120 57600\n");
break;
case 115200:
control[0] = MCP2120_115200;
//printk("mcp2120 115200\n");
break;
}
control[1] = MCP2120_COMMIT;
/* Write control bytes */
sirdev_raw_write(dev, control, 2);
dev->speed = speed;
state = MCP2120_STATE_WAIT_SPEED;
delay = 100;
//printk("mcp2120_change_speed: dongle_speed\n");
break;
case MCP2120_STATE_WAIT_SPEED:
/* Go back to normal mode */
sirdev_set_dtr_rts(dev, FALSE, FALSE);
//printk("mcp2120_change_speed: mcp_wait\n");
break;
default:
IRDA_ERROR("%s(), undefine state %d\n", __func__, state);
ret = -EINVAL;
break;
}
dev->fsm.substate = state;
return (delay > 0) ? delay : ret;
}
/*
* Function mcp2120_reset (driver)
*
* This function resets the mcp2120 dongle.
*
* Info: -set RTS to reset mcp2120
* -set DTR to set mcp2120 software command mode
* -mcp2120 defaults to 9600 baud after reset
*
* Algorithm:
* 0. Set RTS to reset mcp2120.
* 1. Clear RTS and wait for device reset timer of 30 ms (max).
*
*/
#define MCP2120_STATE_WAIT1_RESET (SIRDEV_STATE_DONGLE_RESET+1)
#define MCP2120_STATE_WAIT2_RESET (SIRDEV_STATE_DONGLE_RESET+2)
static int mcp2120_reset(struct sir_dev *dev)
{
unsigned state = dev->fsm.substate;
unsigned delay = 0;
int ret = 0;
IRDA_DEBUG(2, "%s()\n", __func__);
switch (state) {
case SIRDEV_STATE_DONGLE_RESET:
//printk("mcp2120_reset: dongle_reset\n");
/* Reset dongle by setting RTS*/
sirdev_set_dtr_rts(dev, TRUE, TRUE);
state = MCP2120_STATE_WAIT1_RESET;
delay = 50;
break;
case MCP2120_STATE_WAIT1_RESET:
//printk("mcp2120_reset: mcp2120_wait1\n");
/* clear RTS and wait for at least 30 ms. */
sirdev_set_dtr_rts(dev, FALSE, FALSE);
state = MCP2120_STATE_WAIT2_RESET;
delay = 50;
break;
case MCP2120_STATE_WAIT2_RESET:
//printk("mcp2120_reset mcp2120_wait2\n");
/* Go back to normal mode */
sirdev_set_dtr_rts(dev, FALSE, FALSE);
break;
default:
IRDA_ERROR("%s(), undefined state %d\n", __func__, state);
ret = -EINVAL;
break;
}
dev->fsm.substate = state;
return (delay > 0) ? delay : ret;
}
MODULE_AUTHOR("Felix Tang <tangf@eyetap.org>");
MODULE_DESCRIPTION("Microchip MCP2120");
MODULE_LICENSE("GPL");
MODULE_ALIAS("irda-dongle-9"); /* IRDA_MCP2120_DONGLE */
module_init(mcp2120_sir_init);
module_exit(mcp2120_sir_cleanup);
