Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 | /* * Parallel port to Keyboard port adapter driver for Linux * * Copyright (c) 1999-2004 Vojtech Pavlik */ /* * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 as published by * the Free Software Foundation. */ /* * To connect an AT or XT keyboard to the parallel port, a fairly simple adapter * can be made: * * Parallel port Keyboard port * * +5V --------------------- +5V (4) * * ______ * +5V -------|______|--. * | * ACK (10) ------------| * |--- KBD CLOCK (5) * STROBE (1) ---|<|----' * * ______ * +5V -------|______|--. * | * BUSY (11) -----------| * |--- KBD DATA (1) * AUTOFD (14) --|<|----' * * GND (18-25) ------------- GND (3) * * The diodes can be fairly any type, and the resistors should be somewhere * around 5 kOhm, but the adapter will likely work without the resistors, * too. * * The +5V source can be taken either from USB, from mouse or keyboard ports, * or from a joystick port. Unfortunately, the parallel port of a PC doesn't * have a +5V pin, and feeding the keyboard from signal pins is out of question * with 300 mA power reqirement of a typical AT keyboard. */ #include <linux/module.h> #include <linux/parport.h> #include <linux/init.h> #include <linux/serio.h> MODULE_AUTHOR("Vojtech Pavlik <vojtech@ucw.cz>"); MODULE_DESCRIPTION("Parallel port to Keyboard port adapter driver"); MODULE_LICENSE("GPL"); static unsigned int parkbd_pp_no; module_param_named(port, parkbd_pp_no, int, 0); MODULE_PARM_DESC(port, "Parallel port the adapter is connected to (default is 0)"); static unsigned int parkbd_mode = SERIO_8042; module_param_named(mode, parkbd_mode, uint, 0); MODULE_PARM_DESC(mode, "Mode of operation: XT = 0/AT = 1 (default)"); #define PARKBD_CLOCK 0x01 /* Strobe & Ack */ #define PARKBD_DATA 0x02 /* AutoFd & Busy */ static int parkbd_buffer; static int parkbd_counter; static unsigned long parkbd_last; static int parkbd_writing; static unsigned long parkbd_start; static struct pardevice *parkbd_dev; static struct serio *parkbd_port; static int parkbd_readlines(void) { return (parport_read_status(parkbd_dev->port) >> 6) ^ 2; } static void parkbd_writelines(int data) { parport_write_control(parkbd_dev->port, (~data & 3) | 0x10); } static int parkbd_write(struct serio *port, unsigned char c) { unsigned char p; if (!parkbd_mode) return -1; p = c ^ (c >> 4); p = p ^ (p >> 2); p = p ^ (p >> 1); parkbd_counter = 0; parkbd_writing = 1; parkbd_buffer = c | (((int) (~p & 1)) << 8) | 0x600; parkbd_writelines(2); return 0; } static void parkbd_interrupt(void *dev_id) { if (parkbd_writing) { if (parkbd_counter && ((parkbd_counter == 11) || time_after(jiffies, parkbd_last + HZ/100))) { parkbd_counter = 0; parkbd_buffer = 0; parkbd_writing = 0; parkbd_writelines(3); return; } parkbd_writelines(((parkbd_buffer >> parkbd_counter++) & 1) | 2); if (parkbd_counter == 11) { parkbd_counter = 0; parkbd_buffer = 0; parkbd_writing = 0; parkbd_writelines(3); } } else { if ((parkbd_counter == parkbd_mode + 10) || time_after(jiffies, parkbd_last + HZ/100)) { parkbd_counter = 0; parkbd_buffer = 0; } parkbd_buffer |= (parkbd_readlines() >> 1) << parkbd_counter++; if (parkbd_counter == parkbd_mode + 10) serio_interrupt(parkbd_port, (parkbd_buffer >> (2 - parkbd_mode)) & 0xff, 0); } parkbd_last = jiffies; } static int parkbd_getport(void) { struct parport *pp; pp = parport_find_number(parkbd_pp_no); if (pp == NULL) { printk(KERN_ERR "parkbd: no such parport\n"); return -ENODEV; } parkbd_dev = parport_register_device(pp, "parkbd", NULL, NULL, parkbd_interrupt, PARPORT_DEV_EXCL, NULL); parport_put_port(pp); if (!parkbd_dev) return -ENODEV; if (parport_claim(parkbd_dev)) { parport_unregister_device(parkbd_dev); return -EBUSY; } parkbd_start = jiffies; return 0; } static struct serio * __init parkbd_allocate_serio(void) { struct serio *serio; serio = kzalloc(sizeof(struct serio), GFP_KERNEL); if (serio) { serio->id.type = parkbd_mode; serio->write = parkbd_write, strlcpy(serio->name, "PARKBD AT/XT keyboard adapter", sizeof(serio->name)); snprintf(serio->phys, sizeof(serio->phys), "%s/serio0", parkbd_dev->port->name); } return serio; } static int __init parkbd_init(void) { int err; err = parkbd_getport(); if (err) return err; parkbd_port = parkbd_allocate_serio(); if (!parkbd_port) { parport_release(parkbd_dev); return -ENOMEM; } parkbd_writelines(3); serio_register_port(parkbd_port); printk(KERN_INFO "serio: PARKBD %s adapter on %s\n", parkbd_mode ? "AT" : "XT", parkbd_dev->port->name); return 0; } static void __exit parkbd_exit(void) { parport_release(parkbd_dev); serio_unregister_port(parkbd_port); parport_unregister_device(parkbd_dev); } module_init(parkbd_init); module_exit(parkbd_exit); |