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/delay.h>
  16 #include <linux/pci.h>
  17 #include <linux/fb.h>
  18
  19 #include <asm/io.h>
  20
  21 #include "nv_type.h"
  22 #include "nv_local.h"
  23 #include "nv_proto.h"
  24
  25 #include "../edid.h"
  26
  27 static void nvidia_gpio_setscl(void *data, int state)
  28 {
  29         struct nvidia_i2c_chan *chan = data;
  30         struct nvidia_par *par = chan->par;
  31         u32 val;
  32
  33         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  34         val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;
  35
  36         if (state)
  37                 val |= 0x20;
  38         else
  39                 val &= ~0x20;
  40
  41         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  42         VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
  43 }
  44
  45 static void nvidia_gpio_setsda(void *data, int state)
  46 {
  47         struct nvidia_i2c_chan *chan = data;
  48         struct nvidia_par *par = chan->par;
  49         u32 val;
  50
  51         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  52         val = VGA_RD08(par->PCIO, 0x3d5) & 0xf0;
  53
  54         if (state)
  55                 val |= 0x10;
  56         else
  57                 val &= ~0x10;
  58
  59         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base + 1);
  60         VGA_WR08(par->PCIO, 0x3d5, val | 0x1);
  61 }
  62
  63 static int nvidia_gpio_getscl(void *data)
  64 {
  65         struct nvidia_i2c_chan *chan = data;
  66         struct nvidia_par *par = chan->par;
  67         u32 val = 0;
  68
  69         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
  70         if (VGA_RD08(par->PCIO, 0x3d5) & 0x04)
  71                 val = 1;
  72
  73         val = VGA_RD08(par->PCIO, 0x3d5);
  74
  75         return val;
  76 }
  77
  78 static int nvidia_gpio_getsda(void *data)
  79 {
  80         struct nvidia_i2c_chan *chan = data;
  81         struct nvidia_par *par = chan->par;
  82         u32 val = 0;
  83
  84         VGA_WR08(par->PCIO, 0x3d4, chan->ddc_base);
  85         if (VGA_RD08(par->PCIO, 0x3d5) & 0x08)
  86                 val = 1;
  87
  88         return val;
  89 }
  90
  91 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name)
  92 {
  93         int rc;
  94
  95         strcpy(chan->adapter.name, name);
  96         chan->adapter.owner = THIS_MODULE;
  97         chan->adapter.id = I2C_HW_B_NVIDIA;
  98         chan->adapter.algo_data = &chan->algo;
  99         chan->adapter.dev.parent = &chan->par->pci_dev->dev;
 100         chan->algo.setsda = nvidia_gpio_setsda;
 101         chan->algo.setscl = nvidia_gpio_setscl;
 102         chan->algo.getsda = nvidia_gpio_getsda;
 103         chan->algo.getscl = nvidia_gpio_getscl;
 104         chan->algo.udelay = 40;
 105         chan->algo.timeout = msecs_to_jiffies(2);
 106         chan->algo.data = chan;
 107
 108         i2c_set_adapdata(&chan->adapter, chan);
 109
 110         /* Raise SCL and SDA */
 111         nvidia_gpio_setsda(chan, 1);
 112         nvidia_gpio_setscl(chan, 1);
 113         udelay(20);
 114
 115         rc = i2c_bit_add_bus(&chan->adapter);
 116         if (rc == 0)
 117                 dev_dbg(&chan->par->pci_dev->dev,
 118                         "I2C bus %s registered.\n", name);
 119         else {
 120                 dev_warn(&chan->par->pci_dev->dev,
 121                          "Failed to register I2C bus %s.\n", name);
 122                 chan->par = NULL;
 123         }
 124
 125         return rc;
 126 }
 127
 128 void nvidia_create_i2c_busses(struct nvidia_par *par)
 129 {
 130         par->bus = 3;
 131
 132         par->chan[0].par = par;
 133         par->chan[1].par = par;
 134         par->chan[2].par = par;
 135
 136         par->chan[0].ddc_base = 0x3e;
 137         nvidia_setup_i2c_bus(&par->chan[0], "nvidia #0");
 138
 139         par->chan[1].ddc_base = 0x36;
 140         nvidia_setup_i2c_bus(&par->chan[1], "nvidia #1");
 141
 142         par->chan[2].ddc_base = 0x50;
 143         nvidia_setup_i2c_bus(&par->chan[2], "nvidia #2");
 144 }
 145
 146 void nvidia_delete_i2c_busses(struct nvidia_par *par)
 147 {
 148         if (par->chan[0].par)
 149                 i2c_del_adapter(&par->chan[0].adapter);
 150         par->chan[0].par = NULL;
 151
 152         if (par->chan[1].par)
 153                 i2c_del_adapter(&par->chan[1].adapter);
 154         par->chan[1].par = NULL;
 155
 156         if (par->chan[2].par)
 157                 i2c_del_adapter(&par->chan[2].adapter);
 158         par->chan[2].par = NULL;
 159
 160 }
 161
 162 static u8 *nvidia_do_probe_i2c_edid(struct nvidia_i2c_chan *chan)
 163 {
 164         u8 start = 0x0;
 165         struct i2c_msg msgs[] = {
 166                 {
 167                  .addr = 0x50,
 168                  .len = 1,
 169                  .buf = &start,
 170                  }, {
 171                      .addr = 0x50,
 172                      .flags = I2C_M_RD,
 173                      .len = EDID_LENGTH,
 174                      },
 175         };
 176         u8 *buf;
 177
 178         if (!chan->par)
 179                 return NULL;
 180
 181         buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
 182         if (!buf) {
 183                 dev_warn(&chan->par->pci_dev->dev, "Out of memory!\n");
 184                 return NULL;
 185         }
 186         msgs[1].buf = buf;
 187
 188         if (i2c_transfer(&chan->adapter, msgs, 2) == 2)
 189                 return buf;
 190         dev_dbg(&chan->par->pci_dev->dev, "Unable to read EDID block.\n");
 191         kfree(buf);
 192         return NULL;
 193 }
 194
 195 int nvidia_probe_i2c_connector(struct fb_info *info, int conn, u8 **out_edid)
 196 {
 197         struct nvidia_par *par = info->par;
 198         u8 *edid = NULL;
 199         int i;
 200
 201         for (i = 0; i < 3; i++) {
 202                 /* Do the real work */
 203                 edid = nvidia_do_probe_i2c_edid(&par->chan[conn - 1]);
 204                 if (edid)
 205                         break;
 206         }
 207
 208         if (!edid && conn == 1) {
 209                 /* try to get from firmware */
 210                 const u8 *e = fb_firmware_edid(info->device);
 211
 212                 if (e != NULL)
 213                         edid = kmemdup(e, EDID_LENGTH, GFP_KERNEL);
 214         }
 215
 216         *out_edid = edid;
 217
 218         return (edid) ? 0 : 1;
 219 }