drivers/input/joystick/iforce/iforce-serio.c

   1 /*
   2  * $Id: iforce-serio.c,v 1.4 2002/01/28 22:45:00 jdeneux Exp $
   3  *
   4  *  Copyright (c) 2000-2001 Vojtech Pavlik <vojtech@ucw.cz>
   5  *  Copyright (c) 2001 Johann Deneux <deneux@ifrance.com>
   6  *
   7  *  USB/RS232 I-Force joysticks and wheels.
   8  */
   9
  10 /*
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  24  *
  25  * Should you need to contact me, the author, you can do so either by
  26  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
  27  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
  28  */
  29
  30 #include "iforce.h"
  31
  32 void iforce_serial_xmit(struct iforce *iforce)
  33 {
  34         unsigned char cs;
  35         int i;
  36         unsigned long flags;
  37
  38         if (test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags)) {
  39                 set_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags);
  40                 return;
  41         }
  42
  43         spin_lock_irqsave(&iforce->xmit_lock, flags);
  44
  45 again:
  46         if (iforce->xmit.head == iforce->xmit.tail) {
  47                 clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  48                 spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  49                 return;
  50         }
  51
  52         cs = 0x2b;
  53
  54         serio_write(iforce->serio, 0x2b);
  55
  56         serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  57         cs ^= iforce->xmit.buf[iforce->xmit.tail];
  58         XMIT_INC(iforce->xmit.tail, 1);
  59
  60         for (i=iforce->xmit.buf[iforce->xmit.tail]; i >= 0; --i) {
  61                 serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  62                 cs ^= iforce->xmit.buf[iforce->xmit.tail];
  63                 XMIT_INC(iforce->xmit.tail, 1);
  64         }
  65
  66         serio_write(iforce->serio, cs);
  67
  68         if (test_and_clear_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags))
  69                 goto again;
  70
  71         clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  72
  73         spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  74 }
  75
  76 static void iforce_serio_write_wakeup(struct serio *serio)
  77 {
  78         iforce_serial_xmit((struct iforce *)serio->private);
  79 }
  80
  81 static irqreturn_t iforce_serio_irq(struct serio *serio,
  82                 unsigned char data, unsigned int flags, struct pt_regs *regs)
  83 {
  84         struct iforce* iforce = serio->private;
  85
  86         if (!iforce->pkt) {
  87                 if (data == 0x2b)
  88                         iforce->pkt = 1;
  89                 goto out;
  90         }
  91
  92         if (!iforce->id) {
  93                 if (data > 3 && data != 0xff)
  94                         iforce->pkt = 0;
  95                 else
  96                         iforce->id = data;
  97                 goto out;
  98         }
  99
 100         if (!iforce->len) {
 101                 if (data > IFORCE_MAX_LENGTH) {
 102                         iforce->pkt = 0;
 103                         iforce->id = 0;
 104                 } else {
 105                         iforce->len = data;
 106                 }
 107                 goto out;
 108         }
 109
 110         if (iforce->idx < iforce->len) {
 111                 iforce->csum += iforce->data[iforce->idx++] = data;
 112                 goto out;
 113         }
 114
 115         if (iforce->idx == iforce->len) {
 116                 iforce_process_packet(iforce, (iforce->id << 8) | iforce->idx, iforce->data, regs);
 117                 iforce->pkt = 0;
 118                 iforce->id  = 0;
 119                 iforce->len = 0;
 120                 iforce->idx = 0;
 121                 iforce->csum = 0;
 122         }
 123 out:
 124         return IRQ_HANDLED;
 125 }
 126
 127 static void iforce_serio_connect(struct serio *serio, struct serio_driver *drv)
 128 {
 129         struct iforce *iforce;
 130         if (serio->type != (SERIO_RS232 | SERIO_IFORCE))
 131                 return;
 132
 133         if (!(iforce = kmalloc(sizeof(struct iforce), GFP_KERNEL))) return;
 134         memset(iforce, 0, sizeof(struct iforce));
 135
 136         iforce->bus = IFORCE_232;
 137         iforce->serio = serio;
 138         serio->private = iforce;
 139
 140         if (serio_open(serio, drv)) {
 141                 kfree(iforce);
 142                 return;
 143         }
 144
 145         if (iforce_init_device(iforce)) {
 146                 serio_close(serio);
 147                 kfree(iforce);
 148                 return;
 149         }
 150 }
 151
 152 static void iforce_serio_disconnect(struct serio *serio)
 153 {
 154         struct iforce* iforce = serio->private;
 155
 156         input_unregister_device(&iforce->dev);
 157         serio_close(serio);
 158         kfree(iforce);
 159 }
 160
 161 struct serio_driver iforce_serio_drv = {
 162         .driver         = {
 163                 .name   = "iforce",
 164         },
 165         .description    = "RS232 I-Force joysticks and wheels driver",
 166         .write_wakeup   = iforce_serio_write_wakeup,
 167         .interrupt      = iforce_serio_irq,
 168         .connect        = iforce_serio_connect,
 169         .disconnect     = iforce_serio_disconnect,
 170 };