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/config.h>
  31 #include <linux/kernel.h>
  32 #include <linux/module.h>
  33 #include <linux/init.h>
  34 #include <linux/pci.h>
  35 #include <linux/i2c.h>
  36 #include <linux/i2c-algo-bit.h>
  37 #include <asm/io.h>
  38
  39 /* the only registers we use */
  40 #define REG             0x78
  41 #define REG2            0x70
  42
  43 /* bit locations in the register */
  44 #define DDC_ENAB        0x00040000
  45 #define DDC_SCL_OUT     0x00080000
  46 #define DDC_SDA_OUT     0x00100000
  47 #define DDC_SCL_IN      0x00200000
  48 #define DDC_SDA_IN      0x00400000
  49 #define I2C_ENAB        0x00800000
  50 #define I2C_SCL_OUT     0x01000000
  51 #define I2C_SDA_OUT     0x02000000
  52 #define I2C_SCL_IN      0x04000000
  53 #define I2C_SDA_IN      0x08000000
  54
  55 /* initialization states */
  56 #define INIT2           0x2
  57 #define INIT3           0x4
  58
  59 /* delays */
  60 #define CYCLE_DELAY     10
  61 #define TIMEOUT         (HZ / 2)
  62
  63
  64 static void __iomem *ioaddr;
  65
  66 /* The voo GPIO registers don't have individual masks for each bit
  67    so we always have to read before writing. */
  68
  69 static void bit_vooi2c_setscl(void *data, int val)
  70 {
  71         unsigned int r;
  72         r = readl(ioaddr + REG);
  73         if (val)
  74                 r |= I2C_SCL_OUT;
  75         else
  76                 r &= ~I2C_SCL_OUT;
  77         writel(r, ioaddr + REG);
  78         readl(ioaddr + REG);    /* flush posted write */
  79 }
  80
  81 static void bit_vooi2c_setsda(void *data, int val)
  82 {
  83         unsigned int r;
  84         r = readl(ioaddr + REG);
  85         if (val)
  86                 r |= I2C_SDA_OUT;
  87         else
  88                 r &= ~I2C_SDA_OUT;
  89         writel(r, ioaddr + REG);
  90         readl(ioaddr + REG);    /* flush posted write */
  91 }
  92
  93 /* The GPIO pins are open drain, so the pins always remain outputs.
  94    We rely on the i2c-algo-bit routines to set the pins high before
  95    reading the input from other chips. */
  96
  97 static int bit_vooi2c_getscl(void *data)
  98 {
  99         return (0 != (readl(ioaddr + REG) & I2C_SCL_IN));
 100 }
 101
 102 static int bit_vooi2c_getsda(void *data)
 103 {
 104         return (0 != (readl(ioaddr + REG) & I2C_SDA_IN));
 105 }
 106
 107 static void bit_vooddc_setscl(void *data, int val)
 108 {
 109         unsigned int r;
 110         r = readl(ioaddr + REG);
 111         if (val)
 112                 r |= DDC_SCL_OUT;
 113         else
 114                 r &= ~DDC_SCL_OUT;
 115         writel(r, ioaddr + REG);
 116         readl(ioaddr + REG);    /* flush posted write */
 117 }
 118
 119 static void bit_vooddc_setsda(void *data, int val)
 120 {
 121         unsigned int r;
 122         r = readl(ioaddr + REG);
 123         if (val)
 124                 r |= DDC_SDA_OUT;
 125         else
 126                 r &= ~DDC_SDA_OUT;
 127         writel(r, ioaddr + REG);
 128         readl(ioaddr + REG);    /* flush posted write */
 129 }
 130
 131 static int bit_vooddc_getscl(void *data)
 132 {
 133         return (0 != (readl(ioaddr + REG) & DDC_SCL_IN));
 134 }
 135
 136 static int bit_vooddc_getsda(void *data)
 137 {
 138         return (0 != (readl(ioaddr + REG) & DDC_SDA_IN));
 139 }
 140
 141 static int config_v3(struct pci_dev *dev)
 142 {
 143         unsigned long cadr;
 144
 145         /* map Voodoo3 memory */
 146         cadr = dev->resource[0].start;
 147         cadr &= PCI_BASE_ADDRESS_MEM_MASK;
 148         ioaddr = ioremap_nocache(cadr, 0x1000);
 149         if (ioaddr) {
 150                 writel(0x8160, ioaddr + REG2);
 151                 writel(0xcffc0020, ioaddr + REG);
 152                 dev_info(&dev->dev, "Using Banshee/Voodoo3 I2C device at %p\n", ioaddr);
 153                 return 0;
 154         }
 155         return -ENODEV;
 156 }
 157
 158 static struct i2c_algo_bit_data voo_i2c_bit_data = {
 159         .setsda         = bit_vooi2c_setsda,
 160         .setscl         = bit_vooi2c_setscl,
 161         .getsda         = bit_vooi2c_getsda,
 162         .getscl         = bit_vooi2c_getscl,
 163         .udelay         = CYCLE_DELAY,
 164         .mdelay         = CYCLE_DELAY,
 165         .timeout        = TIMEOUT
 166 };
 167
 168 static struct i2c_adapter voodoo3_i2c_adapter = {
 169         .owner          = THIS_MODULE,
 170         .class          = I2C_CLASS_TV_ANALOG,
 171         .name           = "I2C Voodoo3/Banshee adapter",
 172         .algo_data      = &voo_i2c_bit_data,
 173 };
 174
 175 static struct i2c_algo_bit_data voo_ddc_bit_data = {
 176         .setsda         = bit_vooddc_setsda,
 177         .setscl         = bit_vooddc_setscl,
 178         .getsda         = bit_vooddc_getsda,
 179         .getscl         = bit_vooddc_getscl,
 180         .udelay         = CYCLE_DELAY,
 181         .mdelay         = CYCLE_DELAY,
 182         .timeout        = TIMEOUT
 183 };
 184
 185 static struct i2c_adapter voodoo3_ddc_adapter = {
 186         .owner          = THIS_MODULE,
 187         .class          = I2C_CLASS_DDC,
 188         .name           = "DDC Voodoo3/Banshee adapter",
 189         .algo_data      = &voo_ddc_bit_data,
 190 };
 191
 192 static struct pci_device_id voodoo3_ids[] __devinitdata = {
 193         { PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_VOODOO3) },
 194         { PCI_DEVICE(PCI_VENDOR_ID_3DFX, PCI_DEVICE_ID_3DFX_BANSHEE) },
 195         { 0, }
 196 };
 197
 198 MODULE_DEVICE_TABLE (pci, voodoo3_ids);
 199
 200 static int __devinit voodoo3_probe(struct pci_dev *dev, const struct pci_device_id *id)
 201 {
 202         int retval;
 203
 204         retval = config_v3(dev);
 205         if (retval)
 206                 return retval;
 207
 208         /* set up the sysfs linkage to our parent device */
 209         voodoo3_i2c_adapter.dev.parent = &dev->dev;
 210         voodoo3_ddc_adapter.dev.parent = &dev->dev;
 211
 212         retval = i2c_bit_add_bus(&voodoo3_i2c_adapter);
 213         if (retval)
 214                 return retval;
 215         retval = i2c_bit_add_bus(&voodoo3_ddc_adapter);
 216         if (retval)
 217                 i2c_bit_del_bus(&voodoo3_i2c_adapter);
 218         return retval;
 219 }
 220
 221 static void __devexit voodoo3_remove(struct pci_dev *dev)
 222 {
 223         i2c_bit_del_bus(&voodoo3_i2c_adapter);
 224         i2c_bit_del_bus(&voodoo3_ddc_adapter);
 225         iounmap(ioaddr);
 226 }
 227
 228 static struct pci_driver voodoo3_driver = {
 229         .name           = "voodoo3_smbus",
 230         .id_table       = voodoo3_ids,
 231         .probe          = voodoo3_probe,
 232         .remove         = __devexit_p(voodoo3_remove),
 233 };
 234
 235 static int __init i2c_voodoo3_init(void)
 236 {
 237         return pci_register_driver(&voodoo3_driver);
 238 }
 239
 240 static void __exit i2c_voodoo3_exit(void)
 241 {
 242         pci_unregister_driver(&voodoo3_driver);
 243 }
 244
 245
 246 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, "
 247                 "Philip Edelbrock <phil@netroedge.com>, "
 248                 "Ralph Metzler <rjkm@thp.uni-koeln.de>, "
 249                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
 250 MODULE_DESCRIPTION("Voodoo3 I2C/SMBus driver");
 251 MODULE_LICENSE("GPL");
 252
 253 module_init(i2c_voodoo3_init);
 254 module_exit(i2c_voodoo3_exit);