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/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/sched.h>
  18 #include <linux/delay.h>
  19 #include <linux/pci.h>
  20 #include <linux/fb.h>
  21 #include <linux/jiffies.h>
  22
  23 #include <asm/io.h>
  24
  25 #include "rivafb.h"
  26 #include "../edid.h"
  27
  28 static void riva_gpio_setscl(void* data, int state)
  29 {
  30         struct riva_i2c_chan    *chan = data;
  31         struct riva_par         *par = chan->par;
  32         u32                     val;
  33
  34         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  35         val = VGA_RD08(par->riva.PCIO, 0x3d5) & 0xf0;
  36
  37         if (state)
  38                 val |= 0x20;
  39         else
  40                 val &= ~0x20;
  41
  42         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  43         VGA_WR08(par->riva.PCIO, 0x3d5, val | 0x1);
  44 }
  45
  46 static void riva_gpio_setsda(void* data, int state)
  47 {
  48         struct riva_i2c_chan    *chan = data;
  49         struct riva_par         *par = chan->par;
  50         u32                     val;
  51
  52         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  53         val = VGA_RD08(par->riva.PCIO, 0x3d5) & 0xf0;
  54
  55         if (state)
  56                 val |= 0x10;
  57         else
  58                 val &= ~0x10;
  59
  60         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base + 1);
  61         VGA_WR08(par->riva.PCIO, 0x3d5, val | 0x1);
  62 }
  63
  64 static int riva_gpio_getscl(void* data)
  65 {
  66         struct riva_i2c_chan    *chan = data;
  67         struct riva_par         *par = chan->par;
  68         u32                     val = 0;
  69
  70         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base);
  71         if (VGA_RD08(par->riva.PCIO, 0x3d5) & 0x04)
  72                 val = 1;
  73
  74         val = VGA_RD08(par->riva.PCIO, 0x3d5);
  75
  76         return val;
  77 }
  78
  79 static int riva_gpio_getsda(void* data)
  80 {
  81         struct riva_i2c_chan    *chan = data;
  82         struct riva_par         *par = chan->par;
  83         u32                     val = 0;
  84
  85         VGA_WR08(par->riva.PCIO, 0x3d4, chan->ddc_base);
  86         if (VGA_RD08(par->riva.PCIO, 0x3d5) & 0x08)
  87                 val = 1;
  88
  89         return val;
  90 }
  91
  92 static int riva_setup_i2c_bus(struct riva_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_RIVA;
  99         chan->adapter.algo_data         = &chan->algo;
 100         chan->adapter.dev.parent        = &chan->par->pdev->dev;
 101         chan->algo.setsda               = riva_gpio_setsda;
 102         chan->algo.setscl               = riva_gpio_setscl;
 103         chan->algo.getsda               = riva_gpio_getsda;
 104         chan->algo.getscl               = riva_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         riva_gpio_setsda(chan, 1);
 113         riva_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->pdev->dev, "I2C bus %s registered.\n", name);
 119         else {
 120                 dev_warn(&chan->par->pdev->dev,
 121                          "Failed to register I2C bus %s.\n", name);
 122                 chan->par = NULL;
 123         }
 124
 125         return rc;
 126 }
 127
 128 void riva_create_i2c_busses(struct riva_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         par->chan[1].ddc_base = 0x36;
 138         par->chan[2].ddc_base = 0x50;
 139         riva_setup_i2c_bus(&par->chan[0], "BUS1");
 140         riva_setup_i2c_bus(&par->chan[1], "BUS2");
 141         riva_setup_i2c_bus(&par->chan[2], "BUS3");
 142 }
 143
 144 void riva_delete_i2c_busses(struct riva_par *par)
 145 {
 146         if (par->chan[0].par)
 147                 i2c_del_adapter(&par->chan[0].adapter);
 148         par->chan[0].par = NULL;
 149
 150         if (par->chan[1].par)
 151                 i2c_del_adapter(&par->chan[1].adapter);
 152         par->chan[1].par = NULL;
 153
 154         if (par->chan[2].par)
 155                 i2c_del_adapter(&par->chan[2].adapter);
 156         par->chan[2].par = NULL;
 157 }
 158
 159 int riva_probe_i2c_connector(struct riva_par *par, int conn, u8 **out_edid)
 160 {
 161         u8 *edid = NULL;
 162
 163         edid = fb_ddc_read(&par->chan[conn-1].adapter);
 164
 165         if (out_edid)
 166                 *out_edid = edid;
 167         if (!edid)
 168                 return 1;
 169
 170         return 0;
 171 }
 172