firmware/drivers/serial.c

   1 /***************************************************************************
   2  *             __________               __   ___.
   3  *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
   4  *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
   5  *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
   6  *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
   7  *                     \/            \/     \/    \/            \/
   8  * $Id$
   9  *
  10  * Copyright (C) 2002 by Alan Korr & Nick Robinson
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version 2
  15  * of the License, or (at your option) any later version.
  16  *
  17  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  18  * KIND, either express or implied.
  19  *
  20  ****************************************************************************/
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <stdarg.h>
  24 #include "button.h"
  25 #include "config.h"
  26 #include "cpu.h"
  27 #include "system.h"
  28 #include "kernel.h"
  29 #include "lcd.h"
  30 #include "serial.h"
  31 #include "iap.h"
  32
  33 #if defined(IPOD_ACCESSORY_PROTOCOL)
  34 static int autobaud = 0;
  35
  36 static void set_bitrate(unsigned int rate)
  37 {
  38     unsigned int divisor;
  39
  40     divisor = 24000000L / rate / 16;
  41     SER0_LCR = 0x80; /* Divisor latch enable */
  42     SER0_DLL = (divisor >> 0) & 0xFF;
  43     SER0_LCR = 0x03; /* Divisor latch disable, 8-N-1 */
  44 }
  45
  46 void serial_setup (void)
  47 {
  48     int tmp;
  49
  50 #if defined(IPOD_COLOR) || defined(IPOD_4G)
  51     /* Route the Tx/Rx pins.  4G Ipod??? */
  52     outl(0x70000018, inl(0x70000018) & ~0xc00);
  53 #elif defined(IPOD_NANO) || defined(IPOD_VIDEO)
  54     /* Route the Tx/Rx pins.  5G Ipod */
  55     (*(volatile unsigned long *)(0x7000008C)) &= ~0x0C;
  56     GPO32_ENABLE &= ~0x0C;
  57 #endif
  58
  59     DEV_EN = DEV_EN | DEV_SER0;
  60     CPU_HI_INT_DIS = SER0_MASK;
  61
  62     DEV_RS |= DEV_SER0;
  63     sleep(1);
  64     DEV_RS &= ~DEV_SER0;
  65
  66     SER0_LCR = 0x80; /* Divisor latch enable */
  67     SER0_DLM = 0x00;
  68     SER0_LCR = 0x03; /* Divisor latch disable, 8-N-1 */
  69     SER0_IER = 0x01;
  70
  71     SER0_FCR = 0x07; /* Tx+Rx FIFO reset and FIFO enable */
  72
  73     CPU_INT_EN |= HI_MASK;
  74     CPU_HI_INT_EN |= SER0_MASK;
  75     tmp = SER0_RBR;
  76
  77     serial_bitrate(0);
  78 }
  79
  80 void serial_bitrate(int rate)
  81 {
  82     if(rate == 0)
  83     {
  84         autobaud = 2;
  85         set_bitrate(115200);
  86     }
  87     else
  88     {
  89         autobaud = 0;
  90         set_bitrate(rate);
  91     }
  92 }
  93
  94 int tx_rdy(void)
  95 {
  96     if((SER0_LSR & 0x20))
  97         return 1;
  98     else
  99         return 0;
 100 }
 101
 102 int rx_rdy(void)
 103 {
 104     if((SER0_LSR & 0x1))
 105         return 1;
 106     else
 107         return 0;
 108 }
 109
 110 void tx_writec(unsigned char c)
 111 {
 112     SER0_THR =(int) c;
 113 }
 114
 115 unsigned char rx_readc(void)
 116 {
 117     return (SER0_RBR & 0xFF);
 118 }
 119
 120 void SERIAL0(void)
 121 {
 122     static int badbaud = 0;
 123     static bool newpkt = true;
 124     char temp;
 125
 126     while(rx_rdy())
 127     {
 128         temp = rx_readc();
 129         if (newpkt && autobaud > 0)
 130         {
 131             if (autobaud == 1)
 132             {
 133                 switch (temp)
 134                 {
 135                     case 0xFF:
 136                     case 0x55:
 137                         break;
 138                     case 0xFC:
 139                         set_bitrate(19200);
 140                         temp = 0xFF;
 141                         break;
 142                     case 0xE0:
 143                         set_bitrate(9600);
 144                         temp = 0xFF;
 145                         break;
 146                     default:
 147                         badbaud++;
 148                         if (badbaud >= 6) /* Switch baud detection mode */
 149                         {
 150                             autobaud = 2;
 151                             set_bitrate(115200);
 152                             badbaud = 0;
 153                         } else {
 154                             set_bitrate(57600);
 155                         }
 156                         continue;
 157                 }
 158             } else {
 159                 switch (temp)
 160                 {
 161                     case 0xFF:
 162                     case 0x55:
 163                         break;
 164                     case 0xFE:
 165                         set_bitrate(57600);
 166                         temp = 0xFF;
 167                         break;
 168                     case 0xFC:
 169                         set_bitrate(38400);
 170                         temp = 0xFF;
 171                         break;
 172                     case 0xE0:
 173                         set_bitrate(19200);
 174                         temp = 0xFF;
 175                         break;
 176                     default:
 177                         badbaud++;
 178                         if (badbaud >= 6) /* Switch baud detection */
 179                         {
 180                             autobaud = 1;
 181                             set_bitrate(57600);
 182                             badbaud = 0;
 183                         } else {
 184                             set_bitrate(115200);
 185                         }
 186                         continue;
 187                 }
 188             }
 189         }
 190         bool pkt = iap_getc(temp);
 191         if(newpkt && !pkt)
 192             autobaud = 0; /* Found good baud */
 193         newpkt = pkt;
 194     }
 195 }
 196 #endif
 197
 198 void dprintf(const char * str, ... )
 199 {
 200     char dprintfbuff[256];
 201     char * ptr;
 202
 203     va_list ap;
 204     va_start(ap, str);
 205
 206     ptr = dprintfbuff;
 207     vsnprintf(ptr,sizeof(dprintfbuff),str,ap);
 208     va_end(ap);
 209
 210     serial_tx((unsigned char *)ptr);
 211 }
 212
 213 void serial_tx(const unsigned char * buf)
 214 {
 215     /*Tx*/
 216     for(;;) {
 217         if(tx_rdy()) {
 218             if(*buf == '\0')
 219                 return;
 220             if(*buf == '\n')
 221                 tx_writec('\r');
 222             tx_writec(*buf);
 223             buf++;
 224         }
 225     }
 226 }