drivers/video/nvidia/nv_i2c.c

   1 /*
   2  * linux/drivers/video/nvidia/nvidia-i2c.c - nVidia i2c
   3  *
   4  * Copyright 2004 Antonino A. Daplas <adaplas @pol.net>
   5  *
   6  * Based on rivafb-i2c.c
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file COPYING in the main directory of this archive
  10  * for more details.
  11  */
  12
  13 #include <linux/config.h>
  14 #include <linux/module.h>
  15 #include <linux/kernel.h>
  16 #include <linux/sched.h>
  17 #include <linux/delay.h>
  18 #include <linux/pci.h>
  19 #include <linux/fb.h>
  20
  21 #include <asm/io.h>
  22
  23 #include "nv_type.h"
  24 #include "nv_local.h"
  25 #include "nv_proto.h"
  26
  27 #include "../edid.h"
  28
  29 static void nvidia_gpio_setscl(void *data, int state)
  30 {
  31         struct nvidia_i2c_chan *chan = data;
  32         struct nvidia_par *par = chan->par;
  33         u32 val;
  34
  35         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  36         val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;
  37
  38         if (state)
  39                 val |= 0x20;
  40         else
  41                 val &= ~0x20;
  42
  43         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  44         VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
  45 }
  46
  47 static void nvidia_gpio_setsda(void *data, int state)
  48 {
  49         struct nvidia_i2c_chan *chan = (struct nvidia_i2c_chan *)data;
  50         struct nvidia_par *par = chan->par;
  51         u32 val;
  52
  53         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  54         val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;
  55
  56         if (state)
  57                 val |= 0x10;
  58         else
  59                 val &= ~0x10;
  60
  61         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  62         VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
  63 }
  64
  65 static int nvidia_gpio_getscl(void *data)
  66 {
  67         struct nvidia_i2c_chan *chan = (struct nvidia_i2c_chan *)data;
  68         struct nvidia_par *par = chan->par;
  69         u32 val = 0;
  70
  71         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
  72         if (VGA_RD08(par->PCIO, 0x3d5) & 0x04)
  73                 val = 1;
  74
  75         val = VGA_RD08(par->PCIO, 0x3d5);
  76
  77         return val;
  78 }
  79
  80 static int nvidia_gpio_getsda(void *data)
  81 {
  82         struct nvidia_i2c_chan *chan = (struct nvidia_i2c_chan *)data;
  83         struct nvidia_par *par = chan->par;
  84         u32 val = 0;
  85
  86         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
  87         if (VGA_RD08(par->PCIO, 0x3d5) & 0x08)
  88                 val = 1;
  89
  90         return val;
  91 }
  92
  93 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name)
  94 {
  95         int rc;
  96
  97         strcpy(chan->adapter.name, name);
  98         chan->adapter.owner = THIS_MODULE;
  99         chan->adapter.id = I2C_HW_B_NVIDIA;
 100         chan->adapter.algo_data = &chan->algo;
 101         chan->adapter.dev.parent = &chan->par->pci_dev->dev;
 102         chan->algo.setsda = nvidia_gpio_setsda;
 103         chan->algo.setscl = nvidia_gpio_setscl;
 104         chan->algo.getsda = nvidia_gpio_getsda;
 105         chan->algo.getscl = nvidia_gpio_getscl;
 106         chan->algo.udelay = 40;
 107         chan->algo.timeout = msecs_to_jiffies(2);
 108         chan->algo.data = chan;
 109
 110         i2c_set_adapdata(&chan->adapter, chan);
 111
 112         /* Raise SCL and SDA */
 113         nvidia_gpio_setsda(chan, 1);
 114         nvidia_gpio_setscl(chan, 1);
 115         udelay(20);
 116
 117         rc = i2c_bit_add_bus(&chan->adapter);
 118         if (rc == 0)
 119                 dev_dbg(&chan->par->pci_dev->dev,
 120                         "I2C bus %s registered.\n", name);
 121         else {
 122                 dev_warn(&chan->par->pci_dev->dev,
 123                          "Failed to register I2C bus %s.\n", name);
 124                 chan->par = NULL;
 125         }
 126
 127         return rc;
 128 }
 129
 130 void nvidia_create_i2c_busses(struct nvidia_par *par)
 131 {
 132         par->bus = 3;
 133
 134         par->chan[0].par = par;
 135         par->chan[1].par = par;
 136         par->chan[2].par = par;
 137
 138         par->chan[0].ddc_base = 0x3e;
 139         nvidia_setup_i2c_bus(&par->chan[0], "BUS1");
 140
 141         par->chan[1].ddc_base = 0x36;
 142         nvidia_setup_i2c_bus(&par->chan[1], "BUS2");
 143
 144         par->chan[2].ddc_base = 0x50;
 145         nvidia_setup_i2c_bus(&par->chan[2], "BUS3");
 146 }
 147
 148 void nvidia_delete_i2c_busses(struct nvidia_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
 164 static u8 *nvidia_do_probe_i2c_edid(struct nvidia_i2c_chan *chan)
 165 {
 166         u8 start = 0x0;
 167         struct i2c_msg msgs[] = {
 168                 {
 169                  .addr = 0x50,
 170                  .len = 1,
 171                  .buf = &start,
 172                  }, {
 173                      .addr = 0x50,
 174                      .flags = I2C_M_RD,
 175                      .len = EDID_LENGTH,
 176                      },
 177         };
 178         u8 *buf;
 179
 180         if (!chan->par)
 181                 return NULL;
 182
 183         buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
 184         if (!buf) {
 185                 dev_warn(&chan->par->pci_dev->dev, "Out of memory!\n");
 186                 return NULL;
 187         }
 188         msgs[1].buf = buf;
 189
 190         if (i2c_transfer(&chan->adapter, msgs, 2) == 2)
 191                 return buf;
 192         dev_dbg(&chan->par->pci_dev->dev, "Unable to read EDID block.\n");
 193         kfree(buf);
 194         return NULL;
 195 }
 196
 197 int nvidia_probe_i2c_connector(struct nvidia_par *par, int conn, u8 **out_edid)
 198 {
 199         u8 *edid = NULL;
 200         int i;
 201
 202         for (i = 0; i < 3; i++) {
 203                 /* Do the real work */
 204                 edid = nvidia_do_probe_i2c_edid(&par->chan[conn - 1]);
 205                 if (edid)
 206                         break;
 207         }
 208         if (out_edid)
 209                 *out_edid = edid;
 210         if (!edid)
 211                 return 1;
 212
 213         return 0;
 214 }