drivers/i2c/busses/i2c-voodoo3.c

   1 /*
   2     voodoo3.c - Part of lm_sensors, Linux kernel modules for hardware
   3               monitoring
   4     Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl>,
   5     Philip Edelbrock <phil@netroedge.com>,
   6     Ralph Metzler <rjkm@thp.uni-koeln.de>, and
   7     Mark D. Studebaker <mdsxyz123@yahoo.com>
   8
   9     Based on code written by Ralph Metzler <rjkm@thp.uni-koeln.de> and
  10     Simon Vogl
  11
  12     This program is free software; you can redistribute it and/or modify
  13     it under the terms of the GNU General Public License as published by
  14     the Free Software Foundation; either version 2 of the License, or
  15     (at your option) any later version.
  16
  17     This program is distributed in the hope that it will be useful,
  18     but WITHOUT ANY WARRANTY; without even the implied warranty of
  19     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20     GNU General Public License for more details.
  21
  22     You should have received a copy of the GNU General Public License
  23     along with this program; if not, write to the Free Software
  24     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  25 */
  26
  27 /* This interfaces to the I2C bus of the Voodoo3 to gain access to
  28     the BT869 and possibly other I2C devices. */
  29
  30 #include <linux/kernel.h>
  31 #include <linux/module.h>
  32 #include <linux/init.h>
  33 #include <linux/pci.h>
  34 #include <linux/i2c.h>
  35 #include <linux/i2c-algo-bit.h>
  36 #include <asm/io.h>
  37
  38 /* the only registers we use */
  39 #define REG             0x78
  40 #define REG2            0x70
  41
  42 /* bit locations in the register */
  43 #define DDC_ENAB        0x00040000
  44 #define DDC_SCL_OUT     0x00080000
  45 #define DDC_SDA_OUT     0x00100000
  46 #define DDC_SCL_IN      0x00200000
  47 #define DDC_SDA_IN      0x00400000
  48 #define I2C_ENAB        0x00800000
  49 #define I2C_SCL_OUT     0x01000000
  50 #define I2C_SDA_OUT     0x02000000
  51 #define I2C_SCL_IN      0x04000000
  52 #define I2C_SDA_IN      0x08000000
  53
  54 /* initialization states */
  55 #define INIT2           0x2
  56 #define INIT3           0x4
  57
  58 /* delays */
  59 #define CYCLE_DELAY     10
  60 #define TIMEOUT         (HZ / 2)
  61
  62
  63 static void __iomem *ioaddr;
  64
  65 /* The voo GPIO registers don't have individual masks for each bit
  66    so we always have to read before writing. */
  67
  68 static void bit_vooi2c_setscl(void *data, int val)
  69 {
  70         unsigned int r;
  71         r = readl(ioaddr + REG);
  72         if (val)
  73                 r |= I2C_SCL_OUT;
  74         else
  75                 r &= ~I2C_SCL_OUT;
  76         writel(r, ioaddr + REG);
  77         readl(ioaddr + REG);    /* flush posted write */
  78 }
  79
  80 static void bit_vooi2c_setsda(void *data, int val)
  81 {
  82         unsigned int r;
  83         r = readl(ioaddr + REG);
  84         if (val)
  85                 r |= I2C_SDA_OUT;
  86         else
  87                 r &= ~I2C_SDA_OUT;
  88         writel(r, ioaddr + REG);
  89         readl(ioaddr + REG);    /* flush posted write */
  90 }
  91
  92 /* The GPIO pins are open drain, so the pins always remain outputs.
  93    We rely on the i2c-algo-bit routines to set the pins high before
  94    reading the input from other chips. */
  95
  96 static int bit_vooi2c_getscl(void *data)
  97 {
  98         return (0 != (readl(ioaddr + REG) & I2C_SCL_IN));
  99 }
 100
 101 static int bit_vooi2c_getsda(void *data)
 102 {
 103         return (0 != (readl(ioaddr + REG) & I2C_SDA_IN));
 104 }
 105
 106 static void bit_vooddc_setscl(void *data, int val)
 107 {
 108         unsigned int r;
 109         r = readl(ioaddr + REG);
 110         if (val)
 111                 r |= DDC_SCL_OUT;
 112         else
 113                 r &= ~DDC_SCL_OUT;
 114         writel(r, ioaddr + REG);
 115         readl(ioaddr + REG);    /* flush posted write */
 116 }
 117
 118 static void bit_vooddc_setsda(void *data, int val)
 119 {
 120         unsigned int r;
 121         r = readl(ioaddr + REG);
 122         if (val)
 123                 r |= DDC_SDA_OUT;
 124         else
 125                 r &= ~DDC_SDA_OUT;
 126         writel(r, ioaddr + REG);
 127         readl(ioaddr + REG);    /* flush posted write */
 128 }
 129
 130 static int bit_vooddc_getscl(void *data)
 131 {
 132         return (0 != (readl(ioaddr + REG) & DDC_SCL_IN));
 133 }
 134
 135 static int bit_vooddc_getsda(void *data)
 136 {
 137         return (0 != (readl(ioaddr + REG) & DDC_SDA_IN));
 138 }
 139
 140 static int config_v3(struct pci_dev *dev)
 141 {
 142         unsigned long cadr;
 143
 144         /* map Voodoo3 memory */
 145         cadr = dev->resource[0].start;
 146         cadr &= PCI_BASE_ADDRESS_MEM_MASK;
 147         ioaddr = ioremap_nocache(cadr, 0x1000);
 148         if (ioaddr) {
 149                 writel(0x8160, ioaddr + REG2);
 150                 writel(0xcffc0020, ioaddr + REG);
 151                 dev_info(&dev->dev, "Using Banshee/Voodoo3 I2C device at %p\n", ioaddr);
 152                 return 0;
 153         }
 154         return -ENODEV;
 155 }
 156
 157 static struct i2c_algo_bit_data voo_i2c_bit_data = {
 158         .setsda         = bit_vooi2c_setsda,
 159         .setscl         = bit_vooi2c_setscl,
 160         .getsda         = bit_vooi2c_getsda,
 161         .getscl         = bit_vooi2c_getscl,
 162         .udelay         = CYCLE_DELAY,
 163         .timeout        = TIMEOUT
 164 };
 165
 166 static struct i2c_adapter voodoo3_i2c_adapter = {
 167         .owner          = THIS_MODULE,
 168         .class          = I2C_CLASS_TV_ANALOG,
 169         .name           = "I2C Voodoo3/Banshee adapter",
 170         .algo_data      = &voo_i2c_bit_data,
 171 };
 172
 173 static struct i2c_algo_bit_data voo_ddc_bit_data = {
 174         .setsda         = bit_vooddc_setsda,
 175         .setscl         = bit_vooddc_setscl,
 176         .getsda         = bit_vooddc_getsda,
 177         .getscl         = bit_vooddc_getscl,
 178         .udelay         = CYCLE_DELAY,
 179         .timeout        = TIMEOUT
 180 };
 181
 182 static struct i2c_adapter voodoo3_ddc_adapter = {
 183         .owner          = THIS_MODULE,
 184         .class          = I2C_CLASS_DDC,
 185         .name           = "DDC Voodoo3/Banshee adapter",
 186         .algo_data      = &voo_ddc_bit_data,
 187 };
 188
 189 static struct pci_device_id voodoo3_ids[] __devinitdata = {
 190         { PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_VOODOO3) },
 191         { PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_BANSHEE) },
 192         { 0, }
 193 };
 194
 195 MODULE_DEVICE_TABLE (pci, voodoo3_ids);
 196
 197 static int __devinit voodoo3_probe(struct pci_dev *dev, const struct pci_device_id *id)
 198 {
 199         int retval;
 200
 201         retval = config_v3(dev);
 202         if (retval)
 203                 return retval;
 204
 205         /* set up the sysfs linkage to our parent device */
 206         voodoo3_i2c_adapter.dev.parent = &dev->dev;
 207         voodoo3_ddc_adapter.dev.parent = &dev->dev;
 208
 209         retval = i2c_bit_add_bus(&voodoo3_i2c_adapter);
 210         if (retval)
 211                 return retval;
 212         retval = i2c_bit_add_bus(&voodoo3_ddc_adapter);
 213         if (retval)
 214                 i2c_bit_del_bus(&voodoo3_i2c_adapter);
 215         return retval;
 216 }
 217
 218 static void __devexit voodoo3_remove(struct pci_dev *dev)
 219 {
 220         i2c_bit_del_bus(&voodoo3_i2c_adapter);
 221         i2c_bit_del_bus(&voodoo3_ddc_adapter);
 222         iounmap(ioaddr);
 223 }
 224
 225 static struct pci_driver voodoo3_driver = {
 226         .name           = "voodoo3_smbus",
 227         .id_table       = voodoo3_ids,
 228         .probe          = voodoo3_probe,
 229         .remove         = __devexit_p(voodoo3_remove),
 230 };
 231
 232 static int __init i2c_voodoo3_init(void)
 233 {
 234         return pci_register_driver(&voodoo3_driver);
 235 }
 236
 237 static void __exit i2c_voodoo3_exit(void)
 238 {
 239         pci_unregister_driver(&voodoo3_driver);
 240 }
 241
 242
 243 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
 244                 "Philip Edelbrock <phil@netroedge.com>, "
 245                 "Ralph Metzler <rjkm@thp.uni-koeln.de>, "
 246                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
 247 MODULE_DESCRIPTION("Voodoo3 I2C/SMBus driver");
 248 MODULE_LICENSE("GPL");
 249
 250 module_init(i2c_voodoo3_init);
 251 module_exit(i2c_voodoo3_exit);