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/module.h>
  14 #include <linux/kernel.h>
  15 #include <linux/sched.h>
  16 #include <linux/delay.h>
  17 #include <linux/pci.h>
  18 #include <linux/fb.h>
  19
  20 #include <asm/io.h>
  21
  22 #include "nv_type.h"
  23 #include "nv_local.h"
  24 #include "nv_proto.h"
  25
  26 #include "../edid.h"
  27
  28 static void nvidia_gpio_setscl(void *data, int state)
  29 {
  30         struct nvidia_i2c_chan *chan = data;
  31         struct nvidia_par *par = chan->par;
  32         u32 val;
  33
  34         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  35         val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;
  36
  37         if (state)
  38                 val |= 0x20;
  39         else
  40                 val &= ~0x20;
  41
  42         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  43         VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
  44 }
  45
  46 static void nvidia_gpio_setsda(void *data, int state)
  47 {
  48         struct nvidia_i2c_chan *chan = data;
  49         struct nvidia_par *par = chan->par;
  50         u32 val;
  51
  52         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  53         val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;
  54
  55         if (state)
  56                 val |= 0x10;
  57         else
  58                 val &= ~0x10;
  59
  60         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  61         VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
  62 }
  63
  64 static int nvidia_gpio_getscl(void *data)
  65 {
  66         struct nvidia_i2c_chan *chan = data;
  67         struct nvidia_par *par = chan->par;
  68         u32 val = 0;
  69
  70         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
  71         if (VGA_RD08(par->PCIO, 0x3d5) & 0x04)
  72                 val = 1;
  73
  74         val = VGA_RD08(par->PCIO, 0x3d5);
  75
  76         return val;
  77 }
  78
  79 static int nvidia_gpio_getsda(void *data)
  80 {
  81         struct nvidia_i2c_chan *chan = data;
  82         struct nvidia_par *par = chan->par;
  83         u32 val = 0;
  84
  85         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
  86         if (VGA_RD08(par->PCIO, 0x3d5) & 0x08)
  87                 val = 1;
  88
  89         return val;
  90 }
  91
  92 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name)
  93 {
  94         int rc;
  95
  96         strcpy(chan->adapter.name, name);
  97         chan->adapter.owner = THIS_MODULE;
  98         chan->adapter.id = I2C_HW_B_NVIDIA;
  99         chan->adapter.algo_data = &chan->algo;
 100         chan->adapter.dev.parent = &chan->par->pci_dev->dev;
 101         chan->algo.setsda = nvidia_gpio_setsda;
 102         chan->algo.setscl = nvidia_gpio_setscl;
 103         chan->algo.getsda = nvidia_gpio_getsda;
 104         chan->algo.getscl = nvidia_gpio_getscl;
 105         chan->algo.udelay = 40;
 106         chan->algo.timeout = msecs_to_jiffies(2);
 107         chan->algo.data = chan;
 108
 109         i2c_set_adapdata(&chan->adapter, chan);
 110
 111         /* Raise SCL and SDA */
 112         nvidia_gpio_setsda(chan, 1);
 113         nvidia_gpio_setscl(chan, 1);
 114         udelay(20);
 115
 116         rc = i2c_bit_add_bus(&chan->adapter);
 117         if (rc == 0)
 118                 dev_dbg(&chan->par->pci_dev->dev,
 119                         "I2C bus %s registered.\n", name);
 120         else {
 121                 dev_warn(&chan->par->pci_dev->dev,
 122                          "Failed to register I2C bus %s.\n", name);
 123                 chan->par = NULL;
 124         }
 125
 126         return rc;
 127 }
 128
 129 void nvidia_create_i2c_busses(struct nvidia_par *par)
 130 {
 131         par->bus = 3;
 132
 133         par->chan[0].par = par;
 134         par->chan[1].par = par;
 135         par->chan[2].par = par;
 136
 137         par->chan[0].ddc_base = 0x3e;
 138         nvidia_setup_i2c_bus(&par->chan[0], "nvidia #0");
 139
 140         par->chan[1].ddc_base = 0x36;
 141         nvidia_setup_i2c_bus(&par->chan[1], "nvidia #1");
 142
 143         par->chan[2].ddc_base = 0x50;
 144         nvidia_setup_i2c_bus(&par->chan[2], "nvidia #2");
 145 }
 146
 147 void nvidia_delete_i2c_busses(struct nvidia_par *par)
 148 {
 149         if (par->chan[0].par)
 150                 i2c_bit_del_bus(&par->chan[0].adapter);
 151         par->chan[0].par = NULL;
 152
 153         if (par->chan[1].par)
 154                 i2c_bit_del_bus(&par->chan[1].adapter);
 155         par->chan[1].par = NULL;
 156
 157         if (par->chan[2].par)
 158                 i2c_bit_del_bus(&par->chan[2].adapter);
 159         par->chan[2].par = NULL;
 160
 161 }
 162
 163 static u8 *nvidia_do_probe_i2c_edid(struct nvidia_i2c_chan *chan)
 164 {
 165         u8 start = 0x0;
 166         struct i2c_msg msgs[] = {
 167                 {
 168                  .addr = 0x50,
 169                  .len = 1,
 170                  .buf = &start,
 171                  }, {
 172                      .addr = 0x50,
 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->pci_dev->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->pci_dev->dev, "Unable to read EDID block.\n");
 192         kfree(buf);
 193         return NULL;
 194 }
 195
 196 int nvidia_probe_i2c_connector(struct fb_info *info, int conn, u8 **out_edid)
 197 {
 198         struct nvidia_par *par = info->par;
 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
 209         if (!edid && conn == 1) {
 210                 /* try to get from firmware */
 211                 const u8 *e = fb_firmware_edid(info->device);
 212
 213                 if (e != NULL)
 214                         edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
 215         }
 216
 217         *out_edid = edid;
 218
 219         return (edid) ? 0 : 1;
 220 }