drivers/video/via/via_i2c.c

   1 /*
   2  * Copyright 1998-2008 VIA Technologies, Inc. All Rights Reserved.
   3  * Copyright 2001-2008 S3 Graphics, Inc. All Rights Reserved.
   4
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU General Public
   7  * License as published by the Free Software Foundation;
   8  * either version 2, or (at your option) any later version.
   9
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTIES OR REPRESENTATIONS; without even
  12  * the implied warranty of MERCHANTABILITY or FITNESS FOR
  13  * A PARTICULAR PURPOSE.See the GNU General Public License
  14  * for more details.
  15
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc.,
  19  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 #include "global.h"
  23
  24 static void via_i2c_setscl(void *data, int state)
  25 {
  26         u8 val;
  27         struct via_i2c_stuff *via_i2c_chan = (struct via_i2c_stuff *)data;
  28
  29         val = viafb_read_reg(VIASR, via_i2c_chan->i2c_port) & 0xF0;
  30         if (state)
  31                 val |= 0x20;
  32         else
  33                 val &= ~0x20;
  34         switch (via_i2c_chan->i2c_port) {
  35         case I2CPORTINDEX:
  36                 val |= 0x01;
  37                 break;
  38         case GPIOPORTINDEX:
  39                 val |= 0x80;
  40                 break;
  41         default:
  42                 DEBUG_MSG("via_i2c: specify wrong i2c port.\n");
  43         }
  44         viafb_write_reg(via_i2c_chan->i2c_port, VIASR, val);
  45 }
  46
  47 static int via_i2c_getscl(void *data)
  48 {
  49         struct via_i2c_stuff *via_i2c_chan = (struct via_i2c_stuff *)data;
  50
  51         if (viafb_read_reg(VIASR, via_i2c_chan->i2c_port) & 0x08)
  52                 return 1;
  53         return 0;
  54 }
  55
  56 static int via_i2c_getsda(void *data)
  57 {
  58         struct via_i2c_stuff *via_i2c_chan = (struct via_i2c_stuff *)data;
  59
  60         if (viafb_read_reg(VIASR, via_i2c_chan->i2c_port) & 0x04)
  61                 return 1;
  62         return 0;
  63 }
  64
  65 static void via_i2c_setsda(void *data, int state)
  66 {
  67         u8 val;
  68         struct via_i2c_stuff *via_i2c_chan = (struct via_i2c_stuff *)data;
  69
  70         val = viafb_read_reg(VIASR, via_i2c_chan->i2c_port) & 0xF0;
  71         if (state)
  72                 val |= 0x10;
  73         else
  74                 val &= ~0x10;
  75         switch (via_i2c_chan->i2c_port) {
  76         case I2CPORTINDEX:
  77                 val |= 0x01;
  78                 break;
  79         case GPIOPORTINDEX:
  80                 val |= 0x40;
  81                 break;
  82         default:
  83                 DEBUG_MSG("via_i2c: specify wrong i2c port.\n");
  84         }
  85         viafb_write_reg(via_i2c_chan->i2c_port, VIASR, val);
  86 }
  87
  88 int viafb_i2c_readbyte(u8 slave_addr, u8 index, u8 *pdata)
  89 {
  90         u8 mm1[] = {0x00};
  91         struct i2c_msg msgs[2];
  92
  93         *pdata = 0;
  94         msgs[0].flags = 0;
  95         msgs[1].flags = I2C_M_RD;
  96         msgs[0].addr = msgs[1].addr = slave_addr / 2;
  97         mm1[0] = index;
  98         msgs[0].len = 1; msgs[1].len = 1;
  99         msgs[0].buf = mm1; msgs[1].buf = pdata;
 100         i2c_transfer(&viaparinfo->i2c_stuff.adapter, msgs, 2);
 101
 102         return 0;
 103 }
 104
 105 int viafb_i2c_writebyte(u8 slave_addr, u8 index, u8 data)
 106 {
 107         u8 msg[2] = { index, data };
 108         struct i2c_msg msgs;
 109
 110         msgs.flags = 0;
 111         msgs.addr = slave_addr / 2;
 112         msgs.len = 2;
 113         msgs.buf = msg;
 114         return i2c_transfer(&viaparinfo->i2c_stuff.adapter, &msgs, 1);
 115 }
 116
 117 int viafb_i2c_readbytes(u8 slave_addr, u8 index, u8 *buff, int buff_len)
 118 {
 119         u8 mm1[] = {0x00};
 120         struct i2c_msg msgs[2];
 121
 122         msgs[0].flags = 0;
 123         msgs[1].flags = I2C_M_RD;
 124         msgs[0].addr = msgs[1].addr = slave_addr / 2;
 125         mm1[0] = index;
 126         msgs[0].len = 1; msgs[1].len = buff_len;
 127         msgs[0].buf = mm1; msgs[1].buf = buff;
 128         i2c_transfer(&viaparinfo->i2c_stuff.adapter, msgs, 2);
 129         return 0;
 130 }
 131
 132 int viafb_create_i2c_bus(void *viapar)
 133 {
 134         int ret;
 135         struct viafb_par *par = (struct viafb_par *)viapar;
 136
 137         strcpy(par->i2c_stuff.adapter.name, "via_i2c");
 138         par->i2c_stuff.i2c_port = 0x0;
 139         par->i2c_stuff.adapter.owner = THIS_MODULE;
 140         par->i2c_stuff.adapter.id = 0x01FFFF;
 141         par->i2c_stuff.adapter.class = 0;
 142         par->i2c_stuff.adapter.algo_data = &par->i2c_stuff.algo;
 143         par->i2c_stuff.adapter.dev.parent = NULL;
 144         par->i2c_stuff.algo.setsda = via_i2c_setsda;
 145         par->i2c_stuff.algo.setscl = via_i2c_setscl;
 146         par->i2c_stuff.algo.getsda = via_i2c_getsda;
 147         par->i2c_stuff.algo.getscl = via_i2c_getscl;
 148         par->i2c_stuff.algo.udelay = 40;
 149         par->i2c_stuff.algo.timeout = 20;
 150         par->i2c_stuff.algo.data = &par->i2c_stuff;
 151
 152         i2c_set_adapdata(&par->i2c_stuff.adapter, &par->i2c_stuff);
 153
 154         /* Raise SCL and SDA */
 155         par->i2c_stuff.i2c_port = I2CPORTINDEX;
 156         via_i2c_setsda(&par->i2c_stuff, 1);
 157         via_i2c_setscl(&par->i2c_stuff, 1);
 158
 159         par->i2c_stuff.i2c_port = GPIOPORTINDEX;
 160         via_i2c_setsda(&par->i2c_stuff, 1);
 161         via_i2c_setscl(&par->i2c_stuff, 1);
 162         udelay(20);
 163
 164         ret = i2c_bit_add_bus(&par->i2c_stuff.adapter);
 165         if (ret == 0)
 166                 DEBUG_MSG("I2C bus %s registered.\n",
 167                 par->i2c_stuff.adapter.name);
 168         else
 169                 DEBUG_MSG("Failed to register I2C bus %s.\n",
 170                         par->i2c_stuff.adapter.name);
 171         return ret;
 172 }
 173
 174 void viafb_delete_i2c_buss(void *par)
 175 {
 176         i2c_del_adapter(&((struct viafb_par *)par)->i2c_stuff.adapter);
 177 }