drivers/video/riva/rivafb-i2c.c

   1 /*
   2  * linux/drivers/video/riva/fbdev-i2c.c - nVidia i2c
   3  *
   4  * Maintained by Ani Joshi <ajoshi@shell.unixbox.com>
   5  *
   6  * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
   7  *
   8  * Based on radeonfb-i2c.c
   9  *
  10  * This file is subject to the terms and conditions of the GNU General Public
  11  * License.  See the file COPYING in the main directory of this archive
  12  * for more details.
  13  */
  14
  15 #include <linux/config.h>
  16 #include <linux/module.h>
  17 #include <linux/kernel.h>
  18 #include <linux/sched.h>
  19 #include <linux/delay.h>
  20 #include <linux/pci.h>
  21 #include <linux/fb.h>
  22 #include <linux/jiffies.h>
  23
  24 #include <asm/io.h>
  25
  26 #include "rivafb.h"
  27 #include "../edid.h"
  28
  29 #define RIVA_DDC        0x50
  30
  31 static void riva_gpio_setscl(void* data, int state)
  32 {
  33         struct riva_i2c_chan    *chan = (struct riva_i2c_chan *)data;
  34         struct riva_par         *par = chan->par;
  35         u32                     val;
  36
  37         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  38         val = VGA_RD08(par->riva.PCIO, 0x3d5) & 0xf0;
  39
  40         if (state)
  41                 val |= 0x20;
  42         else
  43                 val &= ~0x20;
  44
  45         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  46         VGA_WR08(par->riva.PCIO, 0x3d5, val | 0x1);
  47 }
  48
  49 static void riva_gpio_setsda(void* data, int state)
  50 {
  51         struct riva_i2c_chan    *chan = (struct riva_i2c_chan *)data;
  52         struct riva_par         *par = chan->par;
  53         u32                     val;
  54
  55         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  56         val = VGA_RD08(par->riva.PCIO, 0x3d5) & 0xf0;
  57
  58         if (state)
  59                 val |= 0x10;
  60         else
  61                 val &= ~0x10;
  62
  63         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  64         VGA_WR08(par->riva.PCIO, 0x3d5, val | 0x1);
  65 }
  66
  67 static int riva_gpio_getscl(void* data)
  68 {
  69         struct riva_i2c_chan    *chan = (struct riva_i2c_chan *)data;
  70         struct riva_par         *par = chan->par;
  71         u32                     val = 0;
  72
  73         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base);
  74         if (VGA_RD08(par->riva.PCIO, 0x3d5) & 0x04)
  75                 val = 1;
  76
  77         val = VGA_RD08(par->riva.PCIO, 0x3d5);
  78
  79         return val;
  80 }
  81
  82 static int riva_gpio_getsda(void* data)
  83 {
  84         struct riva_i2c_chan    *chan = (struct riva_i2c_chan *)data;
  85         struct riva_par         *par = chan->par;
  86         u32                     val = 0;
  87
  88         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base);
  89         if (VGA_RD08(par->riva.PCIO, 0x3d5) & 0x08)
  90                 val = 1;
  91
  92         return val;
  93 }
  94
  95 #define I2C_ALGO_RIVA   0x0e0000
  96 static int riva_setup_i2c_bus(struct riva_i2c_chan *chan, const char *name)
  97 {
  98         int rc;
  99
 100         strcpy(chan->adapter.name, name);
 101         chan->adapter.owner             = THIS_MODULE;
 102         chan->adapter.id                = I2C_ALGO_RIVA;
 103         chan->adapter.algo_data         = &chan->algo;
 104         chan->adapter.dev.parent        = &chan->par->pdev->dev;
 105         chan->algo.setsda               = riva_gpio_setsda;
 106         chan->algo.setscl               = riva_gpio_setscl;
 107         chan->algo.getsda               = riva_gpio_getsda;
 108         chan->algo.getscl               = riva_gpio_getscl;
 109         chan->algo.udelay               = 40;
 110         chan->algo.timeout              = msecs_to_jiffies(2);
 111         chan->algo.data                 = chan;
 112
 113         i2c_set_adapdata(&chan->adapter, chan);
 114
 115         /* Raise SCL and SDA */
 116         riva_gpio_setsda(chan, 1);
 117         riva_gpio_setscl(chan, 1);
 118         udelay(20);
 119
 120         rc = i2c_bit_add_bus(&chan->adapter);
 121         if (rc == 0)
 122                 dev_dbg(&chan->par->pdev->dev, "I2C bus %s registered.\n", name);
 123         else {
 124                 dev_warn(&chan->par->pdev->dev,
 125                          "Failed to register I2C bus %s.\n", name);
 126                 chan->par = NULL;
 127         }
 128
 129         return rc;
 130 }
 131
 132 void riva_create_i2c_busses(struct riva_par *par)
 133 {
 134         par->bus = 3;
 135
 136         par->chan[0].par        = par;
 137         par->chan[1].par        = par;
 138         par->chan[2].par        = par;
 139
 140         par->chan[0].ddc_base = 0x3e;
 141         par->chan[1].ddc_base = 0x36;
 142         par->chan[2].ddc_base = 0x50;
 143         riva_setup_i2c_bus(&par->chan[0], "BUS1");
 144         riva_setup_i2c_bus(&par->chan[1], "BUS2");
 145         riva_setup_i2c_bus(&par->chan[2], "BUS3");
 146 }
 147
 148 void riva_delete_i2c_busses(struct riva_par *par)
 149 {
 150         if (par->chan[0].par)
 151                 i2c_bit_del_bus(&par->chan[0].adapter);
 152         par->chan[0].par = NULL;
 153
 154         if (par->chan[1].par)
 155                 i2c_bit_del_bus(&par->chan[1].adapter);
 156         par->chan[1].par = NULL;
 157
 158         if (par->chan[2].par)
 159                 i2c_bit_del_bus(&par->chan[2].adapter);
 160         par->chan[2].par = NULL;
 161 }
 162
 163 static u8 *riva_do_probe_i2c_edid(struct riva_i2c_chan *chan)
 164 {
 165         u8 start = 0x0;
 166         struct i2c_msg msgs[] = {
 167                 {
 168                         .addr   = RIVA_DDC,
 169                         .len    = 1,
 170                         .buf    = &start,
 171                 }, {
 172                         .addr   = RIVA_DDC,
 173                         .flags  = I2C_M_RD,
 174                         .len    = EDID_LENGTH,
 175                 },
 176         };
 177         u8 *buf;
 178
 179         if (!chan->par)
 180                 return NULL;
 181
 182         buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
 183         if (!buf) {
 184                 dev_warn(&chan->par->pdev->dev, "Out of memory!\n");
 185                 return NULL;
 186         }
 187         msgs[1].buf = buf;
 188
 189         if (i2c_transfer(&chan->adapter, msgs, 2) == 2)
 190                 return buf;
 191         dev_dbg(&chan->par->pdev->dev, "Unable to read EDID block.\n");
 192         kfree(buf);
 193         return NULL;
 194 }
 195
 196 int riva_probe_i2c_connector(struct riva_par *par, int conn, u8 **out_edid)
 197 {
 198         u8 *edid = NULL;
 199         int i;
 200
 201         for (i = 0; i < 3; i++) {
 202                 /* Do the real work */
 203                 edid = riva_do_probe_i2c_edid(&par->chan[conn-1]);
 204                 if (edid)
 205                         break;
 206         }
 207         if (out_edid)
 208                 *out_edid = edid;
 209         if (!edid)
 210                 return 1;
 211
 212         return 0;
 213 }
 214