drivers/i2c/busses/i2c-prosavage.c

   1 /*
   2  *    kernel/busses/i2c-prosavage.c
   3  *
   4  *    i2c bus driver for S3/VIA 8365/8375 graphics processor.
   5  *    Copyright (c) 2003 Henk Vergonet <henk@god.dyndns.org>
   6  *    Based on code written by:
   7  *      Frodo Looijaard <frodol@dds.nl>,
   8  *      Philip Edelbrock <phil@netroedge.com>,
   9  *      Ralph Metzler <rjkm@thp.uni-koeln.de>, and
  10  *      Mark D. Studebaker <mdsxyz123@yahoo.com>
  11  *      Simon Vogl
  12  *      and others
  13  *
  14  *    Please read the lm_sensors documentation for details on use.
  15  *
  16  *    This program is free software; you can redistribute it and/or modify
  17  *    it under the terms of the GNU General Public License as published by
  18  *    the Free Software Foundation; either version 2 of the License, or
  19  *    (at your option) any later version.
  20  *
  21  *    This program is distributed in the hope that it will be useful,
  22  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  23  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  24  *    GNU General Public License for more details.
  25  *
  26  *    You should have received a copy of the GNU General Public License
  27  *    along with this program; if not, write to the Free Software
  28  *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  29  *
  30  */
  31 /*  18-05-2003 HVE - created
  32  *  14-06-2003 HVE - adapted for lm_sensors2
  33  *  17-06-2003 HVE - linux 2.5.xx compatible
  34  *  18-06-2003 HVE - codingstyle
  35  *  21-06-2003 HVE - compatibility lm_sensors2 and linux 2.5.xx
  36  *                   codingstyle, mmio enabled
  37  *
  38  *  This driver interfaces to the I2C bus of the VIA north bridge embedded
  39  *  ProSavage4/8 devices. Usefull for gaining access to the TV Encoder chips.
  40  *
  41  *  Graphics cores:
  42  *   S3/VIA KM266/VT8375 aka ProSavage8
  43  *   S3/VIA KM133/VT8365 aka Savage4
  44  *
  45  *  Two serial busses are implemented:
  46  *   SERIAL1 - I2C serial communications interface
  47  *   SERIAL2 - DDC2 monitor communications interface
  48  *
  49  *  Tested on a FX41 mainboard, see http://www.shuttle.com
  50  *
  51  *
  52  *  TODO:
  53  *  - integration with prosavage framebuffer device
  54  *    (Additional documentation needed :(
  55  */
  56
  57 #include <linux/config.h>
  58 #include <linux/module.h>
  59 #include <linux/init.h>
  60 #include <linux/pci.h>
  61 #include <linux/i2c.h>
  62 #include <linux/i2c-algo-bit.h>
  63 #include <asm/io.h>
  64
  65 /*
  66  * driver configuration
  67  */
  68 #define MAX_BUSSES      2
  69
  70 struct s_i2c_bus {
  71         void __iomem *mmvga;
  72         int     i2c_reg;
  73         int     adap_ok;
  74         struct i2c_adapter              adap;
  75         struct i2c_algo_bit_data        algo;
  76 };
  77
  78 struct s_i2c_chip {
  79         void __iomem *mmio;
  80         struct s_i2c_bus        i2c_bus[MAX_BUSSES];
  81 };
  82
  83
  84 /*
  85  * i2c configuration
  86  */
  87 #ifndef I2C_HW_B_S3VIA
  88 #define I2C_HW_B_S3VIA  0x18    /* S3VIA ProSavage adapter              */
  89 #endif
  90
  91 /* delays */
  92 #define CYCLE_DELAY     10
  93 #define TIMEOUT         (HZ / 2)
  94
  95
  96 /*
  97  * S3/VIA 8365/8375 registers
  98  */
  99 #define VGA_CR_IX       0x3d4
 100 #define VGA_CR_DATA     0x3d5
 101
 102 #define CR_SERIAL1      0xa0    /* I2C serial communications interface */
 103 #define MM_SERIAL1      0xff20
 104 #define CR_SERIAL2      0xb1    /* DDC2 monitor communications interface */
 105
 106 /* based on vt8365 documentation */
 107 #define I2C_ENAB        0x10
 108 #define I2C_SCL_OUT     0x01
 109 #define I2C_SDA_OUT     0x02
 110 #define I2C_SCL_IN      0x04
 111 #define I2C_SDA_IN      0x08
 112
 113 #define SET_CR_IX(p, val)       writeb((val), (p)->mmvga + VGA_CR_IX)
 114 #define SET_CR_DATA(p, val)     writeb((val), (p)->mmvga + VGA_CR_DATA)
 115 #define GET_CR_DATA(p)          readb((p)->mmvga + VGA_CR_DATA)
 116
 117
 118 /*
 119  * Serial bus line handling
 120  *
 121  * serial communications register as parameter in private data
 122  *
 123  * TODO: locks with other code sections accessing video registers?
 124  */
 125 static void bit_s3via_setscl(void *bus, int val)
 126 {
 127         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 128         unsigned int r;
 129
 130         SET_CR_IX(p, p->i2c_reg);
 131         r = GET_CR_DATA(p);
 132         r |= I2C_ENAB;
 133         if (val) {
 134                 r |= I2C_SCL_OUT;
 135         } else {
 136                 r &= ~I2C_SCL_OUT;
 137         }
 138         SET_CR_DATA(p, r);
 139 }
 140
 141 static void bit_s3via_setsda(void *bus, int val)
 142 {
 143         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 144         unsigned int r;
 145
 146         SET_CR_IX(p, p->i2c_reg);
 147         r = GET_CR_DATA(p);
 148         r |= I2C_ENAB;
 149         if (val) {
 150                 r |= I2C_SDA_OUT;
 151         } else {
 152                 r &= ~I2C_SDA_OUT;
 153         }
 154         SET_CR_DATA(p, r);
 155 }
 156
 157 static int bit_s3via_getscl(void *bus)
 158 {
 159         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 160
 161         SET_CR_IX(p, p->i2c_reg);
 162         return (0 != (GET_CR_DATA(p) & I2C_SCL_IN));
 163 }
 164
 165 static int bit_s3via_getsda(void *bus)
 166 {
 167         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 168
 169         SET_CR_IX(p, p->i2c_reg);
 170         return (0 != (GET_CR_DATA(p) & I2C_SDA_IN));
 171 }
 172
 173
 174 /*
 175  * adapter initialisation
 176  */
 177 static int i2c_register_bus(struct pci_dev *dev, struct s_i2c_bus *p, void __iomem *mmvga, u32 i2c_reg)
 178 {
 179         int ret;
 180         p->adap.owner     = THIS_MODULE;
 181         p->adap.id        = I2C_HW_B_S3VIA;
 182         p->adap.algo_data = &p->algo;
 183         p->adap.dev.parent = &dev->dev;
 184         p->algo.setsda    = bit_s3via_setsda;
 185         p->algo.setscl    = bit_s3via_setscl;
 186         p->algo.getsda    = bit_s3via_getsda;
 187         p->algo.getscl    = bit_s3via_getscl;
 188         p->algo.udelay    = CYCLE_DELAY;
 189         p->algo.mdelay    = CYCLE_DELAY;
 190         p->algo.timeout   = TIMEOUT;
 191         p->algo.data      = p;
 192         p->mmvga          = mmvga;
 193         p->i2c_reg        = i2c_reg;
 194
 195         ret = i2c_bit_add_bus(&p->adap);
 196         if (ret) {
 197                 return ret;
 198         }
 199
 200         p->adap_ok = 1;
 201         return 0;
 202 }
 203
 204
 205 /*
 206  * Cleanup stuff
 207  */
 208 static void prosavage_remove(struct pci_dev *dev)
 209 {
 210         struct s_i2c_chip *chip;
 211         int i, ret;
 212
 213         chip = (struct s_i2c_chip *)pci_get_drvdata(dev);
 214
 215         if (!chip) {
 216                 return;
 217         }
 218         for (i = MAX_BUSSES - 1; i >= 0; i--) {
 219                 if (chip->i2c_bus[i].adap_ok == 0)
 220                         continue;
 221
 222                 ret = i2c_bit_del_bus(&chip->i2c_bus[i].adap);
 223                 if (ret) {
 224                         dev_err(&dev->dev, "%s not removed\n",
 225                                 chip->i2c_bus[i].adap.name);
 226                 }
 227         }
 228         if (chip->mmio) {
 229                 iounmap(chip->mmio);
 230         }
 231         kfree(chip);
 232 }
 233
 234
 235 /*
 236  * Detect chip and initialize it
 237  */
 238 static int __devinit prosavage_probe(struct pci_dev *dev, const struct pci_device_id *id)
 239 {
 240         int ret;
 241         unsigned long base, len;
 242         struct s_i2c_chip *chip;
 243         struct s_i2c_bus  *bus;
 244
 245         pci_set_drvdata(dev, kmalloc(sizeof(struct s_i2c_chip), GFP_KERNEL));
 246         chip = (struct s_i2c_chip *)pci_get_drvdata(dev);
 247         if (chip == NULL) {
 248                 return -ENOMEM;
 249         }
 250
 251         memset(chip, 0, sizeof(struct s_i2c_chip));
 252
 253         base = dev->resource[0].start & PCI_BASE_ADDRESS_MEM_MASK;
 254         len  = dev->resource[0].end - base + 1;
 255         chip->mmio = ioremap_nocache(base, len);
 256
 257         if (chip->mmio == NULL) {
 258                 dev_err(&dev->dev, "ioremap failed\n");
 259                 prosavage_remove(dev);
 260                 return -ENODEV;
 261         }
 262
 263
 264         /*
 265          * Chip initialisation
 266          */
 267         /* Unlock Extended IO Space ??? */
 268
 269
 270         /*
 271          * i2c bus registration
 272          */
 273         bus = &chip->i2c_bus[0];
 274         snprintf(bus->adap.name, sizeof(bus->adap.name),
 275                 "ProSavage I2C bus at %02x:%02x.%x",
 276                 dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
 277         ret = i2c_register_bus(dev, bus, chip->mmio + 0x8000, CR_SERIAL1);
 278         if (ret) {
 279                 goto err_adap;
 280         }
 281         /*
 282          * ddc bus registration
 283          */
 284         bus = &chip->i2c_bus[1];
 285         snprintf(bus->adap.name, sizeof(bus->adap.name),
 286                 "ProSavage DDC bus at %02x:%02x.%x",
 287                 dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
 288         ret = i2c_register_bus(dev, bus, chip->mmio + 0x8000, CR_SERIAL2);
 289         if (ret) {
 290                 goto err_adap;
 291         }
 292         return 0;
 293 err_adap:
 294         dev_err(&dev->dev, "%s failed\n", bus->adap.name);
 295         prosavage_remove(dev);
 296         return ret;
 297 }
 298
 299
 300 /*
 301  * Data for PCI driver interface
 302  */
 303 static struct pci_device_id prosavage_pci_tbl[] = {
 304         { PCI_DEVICE(PCI_VENDOR_ID_S3, PCI_DEVICE_ID_S3_SAVAGE4) },
 305         { PCI_DEVICE(PCI_VENDOR_ID_S3, PCI_DEVICE_ID_S3_PROSAVAGE8) },
 306         { 0, },
 307 };
 308
 309 MODULE_DEVICE_TABLE (pci, prosavage_pci_tbl);
 310
 311 static struct pci_driver prosavage_driver = {
 312         .name           =       "prosavage_smbus",
 313         .id_table       =       prosavage_pci_tbl,
 314         .probe          =       prosavage_probe,
 315         .remove         =       prosavage_remove,
 316 };
 317
 318 static int __init i2c_prosavage_init(void)
 319 {
 320         return pci_register_driver(&prosavage_driver);
 321 }
 322
 323 static void __exit i2c_prosavage_exit(void)
 324 {
 325         pci_unregister_driver(&prosavage_driver);
 326 }
 327
 328 MODULE_DEVICE_TABLE(pci, prosavage_pci_tbl);
 329 MODULE_AUTHOR("Henk Vergonet");
 330 MODULE_DESCRIPTION("ProSavage VIA 8365/8375 smbus driver");
 331 MODULE_LICENSE("GPL");
 332
 333 module_init (i2c_prosavage_init);
 334 module_exit (i2c_prosavage_exit);