drivers/i2c/busses/i2c-amd756.c

   1 /*
   2     Copyright (c) 1999-2002 Merlin Hughes <merlin@merlin.org>
   3
   4     Shamelessly ripped from i2c-piix4.c:
   5
   6     Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
   7     Philip Edelbrock <phil@netroedge.com>
   8
   9     This program is free software; you can redistribute it and/or modify
  10     it under the terms of the GNU General Public License as published by
  11     the Free Software Foundation; either version 2 of the License, or
  12     (at your option) any later version.
  13
  14     This program is distributed in the hope that it will be useful,
  15     but WITHOUT ANY WARRANTY; without even the implied warranty of
  16     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17     GNU General Public License for more details.
  18 */
  19
  20 /*
  21     2002-04-08: Added nForce support. (Csaba Halasz)
  22     2002-10-03: Fixed nForce PnP I/O port. (Michael Steil)
  23     2002-12-28: Rewritten into something that resembles a Linux driver (hch)
  24     2003-11-29: Added back AMD8111 removed by the previous rewrite.
  25                 (Philip Pokorny)
  26 */
  27
  28 /*
  29    Supports AMD756, AMD766, AMD768, AMD8111 and nVidia nForce
  30    Note: we assume there can only be one device, with one SMBus interface.
  31 */
  32
  33 #include <linux/module.h>
  34 #include <linux/pci.h>
  35 #include <linux/kernel.h>
  36 #include <linux/delay.h>
  37 #include <linux/stddef.h>
  38 #include <linux/ioport.h>
  39 #include <linux/i2c.h>
  40 #include <linux/acpi.h>
  41 #include <linux/io.h>
  42
  43 /* AMD756 SMBus address offsets */
  44 #define SMB_ADDR_OFFSET         0xE0
  45 #define SMB_IOSIZE              16
  46 #define SMB_GLOBAL_STATUS       (0x0 + amd756_ioport)
  47 #define SMB_GLOBAL_ENABLE       (0x2 + amd756_ioport)
  48 #define SMB_HOST_ADDRESS        (0x4 + amd756_ioport)
  49 #define SMB_HOST_DATA           (0x6 + amd756_ioport)
  50 #define SMB_HOST_COMMAND        (0x8 + amd756_ioport)
  51 #define SMB_HOST_BLOCK_DATA     (0x9 + amd756_ioport)
  52 #define SMB_HAS_DATA            (0xA + amd756_ioport)
  53 #define SMB_HAS_DEVICE_ADDRESS  (0xC + amd756_ioport)
  54 #define SMB_HAS_HOST_ADDRESS    (0xE + amd756_ioport)
  55 #define SMB_SNOOP_ADDRESS       (0xF + amd756_ioport)
  56
  57 /* PCI Address Constants */
  58
  59 /* address of I/O space */
  60 #define SMBBA           0x058           /* mh */
  61 #define SMBBANFORCE     0x014
  62
  63 /* general configuration */
  64 #define SMBGCFG         0x041           /* mh */
  65
  66 /* silicon revision code */
  67 #define SMBREV          0x008
  68
  69 /* Other settings */
  70 #define MAX_TIMEOUT     500
  71
  72 /* AMD756 constants */
  73 #define AMD756_QUICK            0x00
  74 #define AMD756_BYTE             0x01
  75 #define AMD756_BYTE_DATA        0x02
  76 #define AMD756_WORD_DATA        0x03
  77 #define AMD756_PROCESS_CALL     0x04
  78 #define AMD756_BLOCK_DATA       0x05
  79
  80 static struct pci_driver amd756_driver;
  81 static unsigned short amd756_ioport;
  82
  83 /*
  84   SMBUS event = I/O 28-29 bit 11
  85      see E0 for the status bits and enabled in E2
  86
  87 */
  88 #define GS_ABRT_STS     (1 << 0)
  89 #define GS_COL_STS      (1 << 1)
  90 #define GS_PRERR_STS    (1 << 2)
  91 #define GS_HST_STS      (1 << 3)
  92 #define GS_HCYC_STS     (1 << 4)
  93 #define GS_TO_STS       (1 << 5)
  94 #define GS_SMB_STS      (1 << 11)
  95
  96 #define GS_CLEAR_STS    (GS_ABRT_STS | GS_COL_STS | GS_PRERR_STS | \
  97                          GS_HCYC_STS | GS_TO_STS )
  98
  99 #define GE_CYC_TYPE_MASK        (7)
 100 #define GE_HOST_STC             (1 << 3)
 101 #define GE_ABORT                (1 << 5)
 102
 103
 104 static int amd756_transaction(struct i2c_adapter *adap)
 105 {
 106         int temp;
 107         int result = 0;
 108         int timeout = 0;
 109
 110         dev_dbg(&adap->dev, "Transaction (pre): GS=%04x, GE=%04x, ADD=%04x, "
 111                 "DAT=%04x\n", inw_p(SMB_GLOBAL_STATUS),
 112                 inw_p(SMB_GLOBAL_ENABLE), inw_p(SMB_HOST_ADDRESS),
 113                 inb_p(SMB_HOST_DATA));
 114
 115         /* Make sure the SMBus host is ready to start transmitting */
 116         if ((temp = inw_p(SMB_GLOBAL_STATUS)) & (GS_HST_STS | GS_SMB_STS)) {
 117                 dev_dbg(&adap->dev, "SMBus busy (%04x). Waiting...\n", temp);
 118                 do {
 119                         msleep(1);
 120                         temp = inw_p(SMB_GLOBAL_STATUS);
 121                 } while ((temp & (GS_HST_STS | GS_SMB_STS)) &&
 122                          (timeout++ < MAX_TIMEOUT));
 123                 /* If the SMBus is still busy, we give up */
 124                 if (timeout > MAX_TIMEOUT) {
 125                         dev_dbg(&adap->dev, "Busy wait timeout (%04x)\n", temp);
 126                         goto abort;
 127                 }
 128                 timeout = 0;
 129         }
 130
 131         /* start the transaction by setting the start bit */
 132         outw_p(inw(SMB_GLOBAL_ENABLE) | GE_HOST_STC, SMB_GLOBAL_ENABLE);
 133
 134         /* We will always wait for a fraction of a second! */
 135         do {
 136                 msleep(1);
 137                 temp = inw_p(SMB_GLOBAL_STATUS);
 138         } while ((temp & GS_HST_STS) && (timeout++ < MAX_TIMEOUT));
 139
 140         /* If the SMBus is still busy, we give up */
 141         if (timeout > MAX_TIMEOUT) {
 142                 dev_dbg(&adap->dev, "Completion timeout!\n");
 143                 goto abort;
 144         }
 145
 146         if (temp & GS_PRERR_STS) {
 147                 result = -ENXIO;
 148                 dev_dbg(&adap->dev, "SMBus Protocol error (no response)!\n");
 149         }
 150
 151         if (temp & GS_COL_STS) {
 152                 result = -EIO;
 153                 dev_warn(&adap->dev, "SMBus collision!\n");
 154         }
 155
 156         if (temp & GS_TO_STS) {
 157                 result = -ETIMEDOUT;
 158                 dev_dbg(&adap->dev, "SMBus protocol timeout!\n");
 159         }
 160
 161         if (temp & GS_HCYC_STS)
 162                 dev_dbg(&adap->dev, "SMBus protocol success!\n");
 163
 164         outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
 165
 166 #ifdef DEBUG
 167         if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_CLEAR_STS) != 0x00) {
 168                 dev_dbg(&adap->dev,
 169                         "Failed reset at end of transaction (%04x)\n", temp);
 170         }
 171 #endif
 172
 173         dev_dbg(&adap->dev,
 174                 "Transaction (post): GS=%04x, GE=%04x, ADD=%04x, DAT=%04x\n",
 175                 inw_p(SMB_GLOBAL_STATUS), inw_p(SMB_GLOBAL_ENABLE),
 176                 inw_p(SMB_HOST_ADDRESS), inb_p(SMB_HOST_DATA));
 177
 178         return result;
 179
 180  abort:
 181         dev_warn(&adap->dev, "Sending abort\n");
 182         outw_p(inw(SMB_GLOBAL_ENABLE) | GE_ABORT, SMB_GLOBAL_ENABLE);
 183         msleep(100);
 184         outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
 185         return -EIO;
 186 }
 187
 188 /* Return negative errno on error. */
 189 static s32 amd756_access(struct i2c_adapter * adap, u16 addr,
 190                   unsigned short flags, char read_write,
 191                   u8 command, int size, union i2c_smbus_data * data)
 192 {
 193         int i, len;
 194         int status;
 195
 196         switch (size) {
 197         case I2C_SMBUS_QUICK:
 198                 outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 199                        SMB_HOST_ADDRESS);
 200                 size = AMD756_QUICK;
 201                 break;
 202         case I2C_SMBUS_BYTE:
 203                 outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 204                        SMB_HOST_ADDRESS);
 205                 if (read_write == I2C_SMBUS_WRITE)
 206                         outb_p(command, SMB_HOST_DATA);
 207                 size = AMD756_BYTE;
 208                 break;
 209         case I2C_SMBUS_BYTE_DATA:
 210                 outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 211                        SMB_HOST_ADDRESS);
 212                 outb_p(command, SMB_HOST_COMMAND);
 213                 if (read_write == I2C_SMBUS_WRITE)
 214                         outw_p(data->byte, SMB_HOST_DATA);
 215                 size = AMD756_BYTE_DATA;
 216                 break;
 217         case I2C_SMBUS_WORD_DATA:
 218                 outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 219                        SMB_HOST_ADDRESS);
 220                 outb_p(command, SMB_HOST_COMMAND);
 221                 if (read_write == I2C_SMBUS_WRITE)
 222                         outw_p(data->word, SMB_HOST_DATA);      /* TODO: endian???? */
 223                 size = AMD756_WORD_DATA;
 224                 break;
 225         case I2C_SMBUS_BLOCK_DATA:
 226                 outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 227                        SMB_HOST_ADDRESS);
 228                 outb_p(command, SMB_HOST_COMMAND);
 229                 if (read_write == I2C_SMBUS_WRITE) {
 230                         len = data->block[0];
 231                         if (len < 0)
 232                                 len = 0;
 233                         if (len > 32)
 234                                 len = 32;
 235                         outw_p(len, SMB_HOST_DATA);
 236                         /* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */
 237                         for (i = 1; i <= len; i++)
 238                                 outb_p(data->block[i],
 239                                        SMB_HOST_BLOCK_DATA);
 240                 }
 241                 size = AMD756_BLOCK_DATA;
 242                 break;
 243         default:
 244                 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
 245                 return -EOPNOTSUPP;
 246         }
 247
 248         /* How about enabling interrupts... */
 249         outw_p(size & GE_CYC_TYPE_MASK, SMB_GLOBAL_ENABLE);
 250
 251         status = amd756_transaction(adap);
 252         if (status)
 253                 return status;
 254
 255         if ((read_write == I2C_SMBUS_WRITE) || (size == AMD756_QUICK))
 256                 return 0;
 257
 258
 259         switch (size) {
 260         case AMD756_BYTE:
 261                 data->byte = inw_p(SMB_HOST_DATA);
 262                 break;
 263         case AMD756_BYTE_DATA:
 264                 data->byte = inw_p(SMB_HOST_DATA);
 265                 break;
 266         case AMD756_WORD_DATA:
 267                 data->word = inw_p(SMB_HOST_DATA);      /* TODO: endian???? */
 268                 break;
 269         case AMD756_BLOCK_DATA:
 270                 data->block[0] = inw_p(SMB_HOST_DATA) & 0x3f;
 271                 if(data->block[0] > 32)
 272                         data->block[0] = 32;
 273                 /* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */
 274                 for (i = 1; i <= data->block[0]; i++)
 275                         data->block[i] = inb_p(SMB_HOST_BLOCK_DATA);
 276                 break;
 277         }
 278
 279         return 0;
 280 }
 281
 282 static u32 amd756_func(struct i2c_adapter *adapter)
 283 {
 284         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 285             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 286             I2C_FUNC_SMBUS_BLOCK_DATA;
 287 }
 288
 289 static const struct i2c_algorithm smbus_algorithm = {
 290         .smbus_xfer     = amd756_access,
 291         .functionality  = amd756_func,
 292 };
 293
 294 struct i2c_adapter amd756_smbus = {
 295         .owner          = THIS_MODULE,
 296         .class          = I2C_CLASS_HWMON | I2C_CLASS_SPD,
 297         .algo           = &smbus_algorithm,
 298 };
 299
 300 enum chiptype { AMD756, AMD766, AMD768, NFORCE, AMD8111 };
 301 static const char* chipname[] = {
 302         "AMD756", "AMD766", "AMD768",
 303         "nVidia nForce", "AMD8111",
 304 };
 305
 306 static const struct pci_device_id amd756_ids[] = {
 307         { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_740B),
 308           .driver_data = AMD756 },
 309         { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_7413),
 310           .driver_data = AMD766 },
 311         { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_OPUS_7443),
 312           .driver_data = AMD768 },
 313         { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS),
 314           .driver_data = AMD8111 },
 315         { PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_SMBUS),
 316           .driver_data = NFORCE },
 317         { 0, }
 318 };
 319
 320 MODULE_DEVICE_TABLE (pci, amd756_ids);
 321
 322 static int amd756_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 323 {
 324         int nforce = (id->driver_data == NFORCE);
 325         int error;
 326         u8 temp;
 327
 328         if (amd756_ioport) {
 329                 dev_err(&pdev->dev, "Only one device supported "
 330                        "(you have a strange motherboard, btw)\n");
 331                 return -ENODEV;
 332         }
 333
 334         if (nforce) {
 335                 if (PCI_FUNC(pdev->devfn) != 1)
 336                         return -ENODEV;
 337
 338                 pci_read_config_word(pdev, SMBBANFORCE, &amd756_ioport);
 339                 amd756_ioport &= 0xfffc;
 340         } else { /* amd */
 341                 if (PCI_FUNC(pdev->devfn) != 3)
 342                         return -ENODEV;
 343
 344                 pci_read_config_byte(pdev, SMBGCFG, &temp);
 345                 if ((temp & 128) == 0) {
 346                         dev_err(&pdev->dev,
 347                                 "Error: SMBus controller I/O not enabled!\n");
 348                         return -ENODEV;
 349                 }
 350
 351                 /* Determine the address of the SMBus areas */
 352                 /* Technically it is a dword but... */
 353                 pci_read_config_word(pdev, SMBBA, &amd756_ioport);
 354                 amd756_ioport &= 0xff00;
 355                 amd756_ioport += SMB_ADDR_OFFSET;
 356         }
 357
 358         error = acpi_check_region(amd756_ioport, SMB_IOSIZE,
 359                                   amd756_driver.name);
 360         if (error)
 361                 return -ENODEV;
 362
 363         if (!request_region(amd756_ioport, SMB_IOSIZE, amd756_driver.name)) {
 364                 dev_err(&pdev->dev, "SMB region 0x%x already in use!\n",
 365                         amd756_ioport);
 366                 return -ENODEV;
 367         }
 368
 369         pci_read_config_byte(pdev, SMBREV, &temp);
 370         dev_dbg(&pdev->dev, "SMBREV = 0x%X\n", temp);
 371         dev_dbg(&pdev->dev, "AMD756_smba = 0x%X\n", amd756_ioport);
 372
 373         /* set up the sysfs linkage to our parent device */
 374         amd756_smbus.dev.parent = &pdev->dev;
 375
 376         snprintf(amd756_smbus.name, sizeof(amd756_smbus.name),
 377                  "SMBus %s adapter at %04x", chipname[id->driver_data],
 378                  amd756_ioport);
 379
 380         error = i2c_add_adapter(&amd756_smbus);
 381         if (error)
 382                 goto out_err;
 383
 384         return 0;
 385
 386  out_err:
 387         release_region(amd756_ioport, SMB_IOSIZE);
 388         return error;
 389 }
 390
 391 static void amd756_remove(struct pci_dev *dev)
 392 {
 393         i2c_del_adapter(&amd756_smbus);
 394         release_region(amd756_ioport, SMB_IOSIZE);
 395 }
 396
 397 static struct pci_driver amd756_driver = {
 398         .name           = "amd756_smbus",
 399         .id_table       = amd756_ids,
 400         .probe          = amd756_probe,
 401         .remove         = amd756_remove,
 402 };
 403
 404 module_pci_driver(amd756_driver);
 405
 406 MODULE_AUTHOR("Merlin Hughes <merlin@merlin.org>");
 407 MODULE_DESCRIPTION("AMD756/766/768/8111 and nVidia nForce SMBus driver");
 408 MODULE_LICENSE("GPL");
 409
 410 EXPORT_SYMBOL(amd756_smbus);