hw/st_stds75.c

   1 /*
   2  * QEMU st STDS75 Digital temperature sensor and thermal watchdog emulation
   3  *
   4  * Copyright (c) 2009 yajin <yajin@vm-kernel.org>
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24
  25
  26
  27
  28 #include "hw.h"
  29 #include "qemu-timer.h"
  30 #include "i2c.h"
  31 #include "sysemu.h"
  32 #include "console.h"
  33
  34
  35 struct stds75_s
  36 {
  37     i2c_slave i2c;
  38     qemu_irq irq;
  39
  40     int firstbyte;
  41     uint8_t reg;
  42     uint8_t index;
  43
  44     uint16_t temp;
  45     uint8_t conf;
  46     uint16_t thys;
  47     uint16_t tos;
  48 };
  49
  50 static void stds75_event(i2c_slave * i2c, enum i2c_event event)
  51 {
  52     struct stds75_s *s = (struct stds75_s *) i2c;
  53     printf("stds75_event %d \n", event);
  54     if (event == I2C_START_SEND)
  55         s->firstbyte = 1;
  56 }
  57
  58 static int stds75_rx(i2c_slave * i2c)
  59 {
  60     struct stds75_s *s = (struct stds75_s *) i2c;
  61     printf("stds75_rx s->reg %d \n", s->reg);
  62     uint8_t ret = 0;
  63
  64     switch (s->reg)
  65     {
  66     case 0x0:
  67         ret = (s->temp >> ((1 - s->index) * 8)) & 0xff;
  68         break;
  69     case 0x1:
  70         ret = s->conf;
  71         break;
  72     case 0x2:
  73         /*first byte is the MSB */
  74         ret = (s->thys >> ((1 - s->index) * 8)) & 0xff;
  75         break;
  76     case 0x03:
  77         ret = (s->tos >> ((1 - s->index) * 8)) & 0xff;
  78         break;
  79     default:
  80         fprintf(stderr, "%s: read from index %d of stds75 \n",
  81                 __FUNCTION__, s->reg);
  82         break;
  83     }
  84     s->index++;
  85     return ret;
  86 }
  87
  88 static int stds75_tx(i2c_slave * i2c, uint8_t data)
  89 {
  90     struct stds75_s *s = (struct stds75_s *) i2c;
  91     printf("stds75_tx %d \n", data);
  92     if (s->firstbyte)
  93     {
  94         s->reg = data;
  95         s->firstbyte = 0;
  96         s->index = 0;
  97     }
  98     else
  99     {
 100         switch (s->reg)
 101         {
 102         case 0x0:
 103             fprintf(stderr, "%s: write to index 0 of stds75 \n", __FUNCTION__);
 104             break;
 105         case 0x1:
 106             s->conf = data;
 107             break;
 108         case 0x2:
 109             /*first byte is the MSB */
 110             s->thys &= (0xff) << (s->index * 8);
 111             s->thys |= data << ((1 - s->index) * 8);
 112             s->index++;
 113             break;
 114         case 0x03:
 115             s->tos &= (0xff) << (s->index * 8);
 116             s->tos |= data << ((1 - s->index) * 8);
 117             s->index++;
 118             break;
 119         default:
 120             fprintf(stderr, "%s: write to index %d of stds75 \n",
 121                     __FUNCTION__, s->reg);
 122             break;
 123
 124         }
 125
 126     }
 127
 128     return 0;
 129 }
 130
 131
 132 static void stds75_reset(struct stds75_s *s)
 133 {
 134     s->thys = 0x4800;
 135     s->tos = 0x5000;
 136 }
 137
 138 i2c_slave *stds75_init(i2c_bus * bus, qemu_irq irq, int i2c_address)
 139 {
 140     struct stds75_s *s = (struct stds75_s *)
 141         i2c_slave_init(bus, i2c_address, sizeof(struct stds75_s));
 142
 143     s->i2c.event = stds75_event;
 144     s->i2c.recv = stds75_rx;
 145     s->i2c.send = stds75_tx;
 146
 147     s->irq = irq;
 148
 149     stds75_reset(s);
 150
 151     //register_savevm("menelaus", -1, 0, menelaus_save, menelaus_load, s);
 152
 153     return &s->i2c;
 154 }