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 #define I2C_ALGO_NVIDIA   0x0e0000
  94 static int nvidia_setup_i2c_bus(struct nvidia_i2c_chan *chan, const char *name)
  95 {
  96         int rc;
  97
  98         strcpy(chan->adapter.name, name);
  99         chan->adapter.owner = THIS_MODULE;
 100         chan->adapter.id = I2C_ALGO_NVIDIA;
 101         chan->adapter.algo_data = &chan->algo;
 102         chan->adapter.dev.parent = &chan->par->pci_dev->dev;
 103         chan->algo.setsda = nvidia_gpio_setsda;
 104         chan->algo.setscl = nvidia_gpio_setscl;
 105         chan->algo.getsda = nvidia_gpio_getsda;
 106         chan->algo.getscl = nvidia_gpio_getscl;
 107         chan->algo.udelay = 40;
 108         chan->algo.timeout = msecs_to_jiffies(2);
 109         chan->algo.data = chan;
 110
 111         i2c_set_adapdata(&chan->adapter, chan);
 112
 113         /* Raise SCL and SDA */
 114         nvidia_gpio_setsda(chan, 1);
 115         nvidia_gpio_setscl(chan, 1);
 116         udelay(20);
 117
 118         rc = i2c_bit_add_bus(&chan->adapter);
 119         if (rc == 0)
 120                 dev_dbg(&chan->par->pci_dev->dev,
 121                         "I2C bus %s registered.\n", name);
 122         else {
 123                 dev_warn(&chan->par->pci_dev->dev,
 124                          "Failed to register I2C bus %s.\n", name);
 125                 chan->par = NULL;
 126         }
 127
 128         return rc;
 129 }
 130
 131 void nvidia_create_i2c_busses(struct nvidia_par *par)
 132 {
 133         par->bus = 3;
 134
 135         par->chan[0].par = par;
 136         par->chan[1].par = par;
 137         par->chan[2].par = par;
 138
 139         par->chan[0].ddc_base = 0x3e;
 140         nvidia_setup_i2c_bus(&par->chan[0], "BUS1");
 141
 142         par->chan[1].ddc_base = 0x36;
 143         nvidia_setup_i2c_bus(&par->chan[1], "BUS2");
 144
 145         par->chan[2].ddc_base = 0x50;
 146         nvidia_setup_i2c_bus(&par->chan[2], "BUS3");
 147 }
 148
 149 void nvidia_delete_i2c_busses(struct nvidia_par *par)
 150 {
 151         if (par->chan[0].par)
 152                 i2c_bit_del_bus(&par->chan[0].adapter);
 153         par->chan[0].par = NULL;
 154
 155         if (par->chan[1].par)
 156                 i2c_bit_del_bus(&par->chan[1].adapter);
 157         par->chan[1].par = NULL;
 158
 159         if (par->chan[2].par)
 160                 i2c_bit_del_bus(&par->chan[2].adapter);
 161         par->chan[2].par = NULL;
 162
 163 }
 164
 165 static u8 *nvidia_do_probe_i2c_edid(struct nvidia_i2c_chan *chan)
 166 {
 167         u8 start = 0x0;
 168         struct i2c_msg msgs[] = {
 169                 {
 170                  .addr = 0x50,
 171                  .len = 1,
 172                  .buf = &start,
 173                  }, {
 174                      .addr = 0x50,
 175                      .flags = I2C_M_RD,
 176                      .len = EDID_LENGTH,
 177                      },
 178         };
 179         u8 *buf;
 180
 181         if (!chan->par)
 182                 return NULL;
 183
 184         buf = kmalloc(EDID_LENGTH, GFP_KERNEL);
 185         if (!buf) {
 186                 dev_warn(&chan->par->pci_dev->dev, "Out of memory!\n");
 187                 return NULL;
 188         }
 189         msgs[1].buf = buf;
 190
 191         if (i2c_transfer(&chan->adapter, msgs, 2) == 2)
 192                 return buf;
 193         dev_dbg(&chan->par->pci_dev->dev, "Unable to read EDID block.\n");
 194         kfree(buf);
 195         return NULL;
 196 }
 197
 198 int nvidia_probe_i2c_connector(struct nvidia_par *par, int conn, u8 **out_edid)
 199 {
 200         u8 *edid = NULL;
 201         int i;
 202
 203         for (i = 0; i < 3; i++) {
 204                 /* Do the real work */
 205                 edid = nvidia_do_probe_i2c_edid(&par->chan[conn - 1]);
 206                 if (edid)
 207                         break;
 208         }
 209         if (out_edid)
 210                 *out_edid = edid;
 211         if (!edid)
 212                 return 1;
 213
 214         return 0;
 215 }