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/module.h>
  58 #include <linux/init.h>
  59 #include <linux/pci.h>
  60 #include <linux/i2c.h>
  61 #include <linux/i2c-algo-bit.h>
  62 #include <asm/io.h>
  63
  64 /*
  65  * driver configuration
  66  */
  67 #define MAX_BUSSES      2
  68
  69 struct s_i2c_bus {
  70         void __iomem *mmvga;
  71         int     i2c_reg;
  72         int     adap_ok;
  73         struct i2c_adapter              adap;
  74         struct i2c_algo_bit_data        algo;
  75 };
  76
  77 struct s_i2c_chip {
  78         void __iomem *mmio;
  79         struct s_i2c_bus        i2c_bus[MAX_BUSSES];
  80 };
  81
  82
  83 /*
  84  * i2c configuration
  85  */
  86 #define CYCLE_DELAY     10
  87 #define TIMEOUT         (HZ / 2)
  88
  89
  90 /*
  91  * S3/VIA 8365/8375 registers
  92  */
  93 #define VGA_CR_IX       0x3d4
  94 #define VGA_CR_DATA     0x3d5
  95
  96 #define CR_SERIAL1      0xa0    /* I2C serial communications interface */
  97 #define MM_SERIAL1      0xff20
  98 #define CR_SERIAL2      0xb1    /* DDC2 monitor communications interface */
  99
 100 /* based on vt8365 documentation */
 101 #define I2C_ENAB        0x10
 102 #define I2C_SCL_OUT     0x01
 103 #define I2C_SDA_OUT     0x02
 104 #define I2C_SCL_IN      0x04
 105 #define I2C_SDA_IN      0x08
 106
 107 #define SET_CR_IX(p, val)       writeb((val), (p)->mmvga + VGA_CR_IX)
 108 #define SET_CR_DATA(p, val)     writeb((val), (p)->mmvga + VGA_CR_DATA)
 109 #define GET_CR_DATA(p)          readb((p)->mmvga + VGA_CR_DATA)
 110
 111
 112 /*
 113  * Serial bus line handling
 114  *
 115  * serial communications register as parameter in private data
 116  *
 117  * TODO: locks with other code sections accessing video registers?
 118  */
 119 static void bit_s3via_setscl(void *bus, int val)
 120 {
 121         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 122         unsigned int r;
 123
 124         SET_CR_IX(p, p->i2c_reg);
 125         r = GET_CR_DATA(p);
 126         r |= I2C_ENAB;
 127         if (val) {
 128                 r |= I2C_SCL_OUT;
 129         } else {
 130                 r &= ~I2C_SCL_OUT;
 131         }
 132         SET_CR_DATA(p, r);
 133 }
 134
 135 static void bit_s3via_setsda(void *bus, int val)
 136 {
 137         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 138         unsigned int r;
 139
 140         SET_CR_IX(p, p->i2c_reg);
 141         r = GET_CR_DATA(p);
 142         r |= I2C_ENAB;
 143         if (val) {
 144                 r |= I2C_SDA_OUT;
 145         } else {
 146                 r &= ~I2C_SDA_OUT;
 147         }
 148         SET_CR_DATA(p, r);
 149 }
 150
 151 static int bit_s3via_getscl(void *bus)
 152 {
 153         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 154
 155         SET_CR_IX(p, p->i2c_reg);
 156         return (0 != (GET_CR_DATA(p) & I2C_SCL_IN));
 157 }
 158
 159 static int bit_s3via_getsda(void *bus)
 160 {
 161         struct s_i2c_bus *p = (struct s_i2c_bus *)bus;
 162
 163         SET_CR_IX(p, p->i2c_reg);
 164         return (0 != (GET_CR_DATA(p) & I2C_SDA_IN));
 165 }
 166
 167
 168 /*
 169  * adapter initialisation
 170  */
 171 static int i2c_register_bus(struct pci_dev *dev, struct s_i2c_bus *p, void __iomem *mmvga, u32 i2c_reg)
 172 {
 173         int ret;
 174         p->adap.owner     = THIS_MODULE;
 175         p->adap.id        = I2C_HW_B_S3VIA;
 176         p->adap.algo_data = &p->algo;
 177         p->adap.dev.parent = &dev->dev;
 178         p->algo.setsda    = bit_s3via_setsda;
 179         p->algo.setscl    = bit_s3via_setscl;
 180         p->algo.getsda    = bit_s3via_getsda;
 181         p->algo.getscl    = bit_s3via_getscl;
 182         p->algo.udelay    = CYCLE_DELAY;
 183         p->algo.timeout   = TIMEOUT;
 184         p->algo.data      = p;
 185         p->mmvga          = mmvga;
 186         p->i2c_reg        = i2c_reg;
 187
 188         ret = i2c_bit_add_bus(&p->adap);
 189         if (ret) {
 190                 return ret;
 191         }
 192
 193         p->adap_ok = 1;
 194         return 0;
 195 }
 196
 197
 198 /*
 199  * Cleanup stuff
 200  */
 201 static void prosavage_remove(struct pci_dev *dev)
 202 {
 203         struct s_i2c_chip *chip;
 204         int i, ret;
 205
 206         chip = (struct s_i2c_chip *)pci_get_drvdata(dev);
 207
 208         if (!chip) {
 209                 return;
 210         }
 211         for (i = MAX_BUSSES - 1; i >= 0; i--) {
 212                 if (chip->i2c_bus[i].adap_ok == 0)
 213                         continue;
 214
 215                 ret = i2c_del_adapter(&chip->i2c_bus[i].adap);
 216                 if (ret) {
 217                         dev_err(&dev->dev, "%s not removed\n",
 218                                 chip->i2c_bus[i].adap.name);
 219                 }
 220         }
 221         if (chip->mmio) {
 222                 iounmap(chip->mmio);
 223         }
 224         kfree(chip);
 225 }
 226
 227
 228 /*
 229  * Detect chip and initialize it
 230  */
 231 static int __devinit prosavage_probe(struct pci_dev *dev, const struct pci_device_id *id)
 232 {
 233         int ret;
 234         unsigned long base, len;
 235         struct s_i2c_chip *chip;
 236         struct s_i2c_bus  *bus;
 237
 238         pci_set_drvdata(dev, kzalloc(sizeof(struct s_i2c_chip), GFP_KERNEL));
 239         chip = (struct s_i2c_chip *)pci_get_drvdata(dev);
 240         if (chip == NULL) {
 241                 return -ENOMEM;
 242         }
 243
 244         base = dev->resource[0].start & PCI_BASE_ADDRESS_MEM_MASK;
 245         len  = dev->resource[0].end - base + 1;
 246         chip->mmio = ioremap_nocache(base, len);
 247
 248         if (chip->mmio == NULL) {
 249                 dev_err(&dev->dev, "ioremap failed\n");
 250                 prosavage_remove(dev);
 251                 return -ENODEV;
 252         }
 253
 254
 255         /*
 256          * Chip initialisation
 257          */
 258         /* Unlock Extended IO Space ??? */
 259
 260
 261         /*
 262          * i2c bus registration
 263          */
 264         bus = &chip->i2c_bus[0];
 265         snprintf(bus->adap.name, sizeof(bus->adap.name),
 266                 "ProSavage I2C bus at %02x:%02x.%x",
 267                 dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
 268         ret = i2c_register_bus(dev, bus, chip->mmio + 0x8000, CR_SERIAL1);
 269         if (ret) {
 270                 goto err_adap;
 271         }
 272         /*
 273          * ddc bus registration
 274          */
 275         bus = &chip->i2c_bus[1];
 276         snprintf(bus->adap.name, sizeof(bus->adap.name),
 277                 "ProSavage DDC bus at %02x:%02x.%x",
 278                 dev->bus->number, PCI_SLOT(dev->devfn), PCI_FUNC(dev->devfn));
 279         ret = i2c_register_bus(dev, bus, chip->mmio + 0x8000, CR_SERIAL2);
 280         if (ret) {
 281                 goto err_adap;
 282         }
 283         return 0;
 284 err_adap:
 285         dev_err(&dev->dev, "%s failed\n", bus->adap.name);
 286         prosavage_remove(dev);
 287         return ret;
 288 }
 289
 290
 291 /*
 292  * Data for PCI driver interface
 293  */
 294 static struct pci_device_id prosavage_pci_tbl[] = {
 295         { PCI_DEVICE(PCI_VENDOR_ID_S3, PCI_DEVICE_ID_S3_SAVAGE4) },
 296         { PCI_DEVICE(PCI_VENDOR_ID_S3, PCI_DEVICE_ID_S3_PROSAVAGE8) },
 297         { 0, },
 298 };
 299
 300 MODULE_DEVICE_TABLE (pci, prosavage_pci_tbl);
 301
 302 static struct pci_driver prosavage_driver = {
 303         .name           =       "prosavage_smbus",
 304         .id_table       =       prosavage_pci_tbl,
 305         .probe          =       prosavage_probe,
 306         .remove         =       prosavage_remove,
 307 };
 308
 309 static int __init i2c_prosavage_init(void)
 310 {
 311         return pci_register_driver(&prosavage_driver);
 312 }
 313
 314 static void __exit i2c_prosavage_exit(void)
 315 {
 316         pci_unregister_driver(&prosavage_driver);
 317 }
 318
 319 MODULE_DEVICE_TABLE(pci, prosavage_pci_tbl);
 320 MODULE_AUTHOR("Henk Vergonet");
 321 MODULE_DESCRIPTION("ProSavage VIA 8365/8375 smbus driver");
 322 MODULE_LICENSE("GPL");
 323
 324 module_init (i2c_prosavage_init);
 325 module_exit (i2c_prosavage_exit);