drivers/i2c/busses/i2c-sis5595.c

   1 /*
   2     Copyright (c) 1998, 1999  Frodo Looijaard <frodol@dds.nl> and
   3     Philip Edelbrock <phil@netroedge.com>
   4
   5     This program is free software; you can redistribute it and/or modify
   6     it under the terms of the GNU General Public License as published by
   7     the Free Software Foundation; either version 2 of the License, or
   8     (at your option) any later version.
   9
  10     This program is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13     GNU General Public License for more details.
  14 */
  15
  16 /* Note: we assume there can only be one SIS5595 with one SMBus interface */
  17
  18 /*
  19    Note: all have mfr. ID 0x1039.
  20    SUPPORTED            PCI ID
  21         5595            0008
  22
  23    Note: these chips contain a 0008 device which is incompatible with the
  24          5595. We recognize these by the presence of the listed
  25          "blacklist" PCI ID and refuse to load.
  26
  27    NOT SUPPORTED        PCI ID          BLACKLIST PCI ID
  28          540            0008            0540
  29          550            0008            0550
  30         5513            0008            5511
  31         5581            0008            5597
  32         5582            0008            5597
  33         5597            0008            5597
  34         5598            0008            5597/5598
  35          630            0008            0630
  36          645            0008            0645
  37          646            0008            0646
  38          648            0008            0648
  39          650            0008            0650
  40          651            0008            0651
  41          730            0008            0730
  42          735            0008            0735
  43          745            0008            0745
  44          746            0008            0746
  45 */
  46
  47 /* TO DO:
  48  * Add Block Transfers (ugly, but supported by the adapter)
  49  * Add adapter resets
  50  */
  51
  52 #include <linux/kernel.h>
  53 #include <linux/module.h>
  54 #include <linux/delay.h>
  55 #include <linux/pci.h>
  56 #include <linux/ioport.h>
  57 #include <linux/init.h>
  58 #include <linux/i2c.h>
  59 #include <linux/acpi.h>
  60 #include <linux/io.h>
  61
  62 static int blacklist[] = {
  63         PCI_DEVICE_ID_SI_540,
  64         PCI_DEVICE_ID_SI_550,
  65         PCI_DEVICE_ID_SI_630,
  66         PCI_DEVICE_ID_SI_645,
  67         PCI_DEVICE_ID_SI_646,
  68         PCI_DEVICE_ID_SI_648,
  69         PCI_DEVICE_ID_SI_650,
  70         PCI_DEVICE_ID_SI_651,
  71         PCI_DEVICE_ID_SI_730,
  72         PCI_DEVICE_ID_SI_735,
  73         PCI_DEVICE_ID_SI_745,
  74         PCI_DEVICE_ID_SI_746,
  75         PCI_DEVICE_ID_SI_5511,  /* 5513 chip has the 0008 device but that ID
  76                                    shows up in other chips so we use the 5511
  77                                    ID for recognition */
  78         PCI_DEVICE_ID_SI_5597,
  79         PCI_DEVICE_ID_SI_5598,
  80         0,                      /* terminates the list */
  81 };
  82
  83 /* Length of ISA address segment */
  84 #define SIS5595_EXTENT          8
  85 /* SIS5595 SMBus registers */
  86 #define SMB_STS_LO              0x00
  87 #define SMB_STS_HI              0x01
  88 #define SMB_CTL_LO              0x02
  89 #define SMB_CTL_HI              0x03
  90 #define SMB_ADDR                0x04
  91 #define SMB_CMD                 0x05
  92 #define SMB_PCNT                0x06
  93 #define SMB_CNT                 0x07
  94 #define SMB_BYTE                0x08
  95 #define SMB_DEV                 0x10
  96 #define SMB_DB0                 0x11
  97 #define SMB_DB1                 0x12
  98 #define SMB_HAA                 0x13
  99
 100 /* PCI Address Constants */
 101 #define SMB_INDEX               0x38
 102 #define SMB_DAT                 0x39
 103 #define SIS5595_ENABLE_REG      0x40
 104 #define ACPI_BASE               0x90
 105
 106 /* Other settings */
 107 #define MAX_TIMEOUT             500
 108
 109 /* SIS5595 constants */
 110 #define SIS5595_QUICK           0x00
 111 #define SIS5595_BYTE            0x02
 112 #define SIS5595_BYTE_DATA       0x04
 113 #define SIS5595_WORD_DATA       0x06
 114 #define SIS5595_PROC_CALL       0x08
 115 #define SIS5595_BLOCK_DATA      0x0A
 116
 117 /* insmod parameters */
 118
 119 /* If force_addr is set to anything different from 0, we forcibly enable
 120    the device at the given address. */
 121 static u16 force_addr;
 122 module_param(force_addr, ushort, 0);
 123 MODULE_PARM_DESC(force_addr, "Initialize the base address of the i2c controller");
 124
 125 static struct pci_driver sis5595_driver;
 126 static unsigned short sis5595_base;
 127 static struct pci_dev *sis5595_pdev;
 128
 129 static u8 sis5595_read(u8 reg)
 130 {
 131         outb(reg, sis5595_base + SMB_INDEX);
 132         return inb(sis5595_base + SMB_DAT);
 133 }
 134
 135 static void sis5595_write(u8 reg, u8 data)
 136 {
 137         outb(reg, sis5595_base + SMB_INDEX);
 138         outb(data, sis5595_base + SMB_DAT);
 139 }
 140
 141 static int sis5595_setup(struct pci_dev *SIS5595_dev)
 142 {
 143         u16 a;
 144         u8 val;
 145         int *i;
 146         int retval;
 147
 148         /* Look for imposters */
 149         for (i = blacklist; *i != 0; i++) {
 150                 struct pci_dev *dev;
 151                 dev = pci_get_device(PCI_VENDOR_ID_SI, *i, NULL);
 152                 if (dev) {
 153                         dev_err(&SIS5595_dev->dev, "Looked for SIS5595 but found unsupported device %.4x\n", *i);
 154                         pci_dev_put(dev);
 155                         return -ENODEV;
 156                 }
 157         }
 158
 159         /* Determine the address of the SMBus areas */
 160         pci_read_config_word(SIS5595_dev, ACPI_BASE, &sis5595_base);
 161         if (sis5595_base == 0 && force_addr == 0) {
 162                 dev_err(&SIS5595_dev->dev, "ACPI base address uninitialized - upgrade BIOS or use force_addr=0xaddr\n");
 163                 return -ENODEV;
 164         }
 165
 166         if (force_addr)
 167                 sis5595_base = force_addr & ~(SIS5595_EXTENT - 1);
 168         dev_dbg(&SIS5595_dev->dev, "ACPI Base address: %04x\n", sis5595_base);
 169
 170         /* NB: We grab just the two SMBus registers here, but this may still
 171          * interfere with ACPI :-(  */
 172         retval = acpi_check_region(sis5595_base + SMB_INDEX, 2,
 173                                    sis5595_driver.name);
 174         if (retval)
 175                 return retval;
 176
 177         if (!request_region(sis5595_base + SMB_INDEX, 2,
 178                             sis5595_driver.name)) {
 179                 dev_err(&SIS5595_dev->dev, "SMBus registers 0x%04x-0x%04x already in use!\n",
 180                         sis5595_base + SMB_INDEX, sis5595_base + SMB_INDEX + 1);
 181                 return -ENODEV;
 182         }
 183
 184         if (force_addr) {
 185                 dev_info(&SIS5595_dev->dev, "forcing ISA address 0x%04X\n", sis5595_base);
 186                 if (pci_write_config_word(SIS5595_dev, ACPI_BASE, sis5595_base)
 187                     != PCIBIOS_SUCCESSFUL)
 188                         goto error;
 189                 if (pci_read_config_word(SIS5595_dev, ACPI_BASE, &a)
 190                     != PCIBIOS_SUCCESSFUL)
 191                         goto error;
 192                 if ((a & ~(SIS5595_EXTENT - 1)) != sis5595_base) {
 193                         /* doesn't work for some chips! */
 194                         dev_err(&SIS5595_dev->dev, "force address failed - not supported?\n");
 195                         goto error;
 196                 }
 197         }
 198
 199         if (pci_read_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, &val)
 200             != PCIBIOS_SUCCESSFUL)
 201                 goto error;
 202         if ((val & 0x80) == 0) {
 203                 dev_info(&SIS5595_dev->dev, "enabling ACPI\n");
 204                 if (pci_write_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, val | 0x80)
 205                     != PCIBIOS_SUCCESSFUL)
 206                         goto error;
 207                 if (pci_read_config_byte(SIS5595_dev, SIS5595_ENABLE_REG, &val)
 208                     != PCIBIOS_SUCCESSFUL)
 209                         goto error;
 210                 if ((val & 0x80) == 0) {
 211                         /* doesn't work for some chips? */
 212                         dev_err(&SIS5595_dev->dev, "ACPI enable failed - not supported?\n");
 213                         goto error;
 214                 }
 215         }
 216
 217         /* Everything is happy */
 218         return 0;
 219
 220 error:
 221         release_region(sis5595_base + SMB_INDEX, 2);
 222         return -ENODEV;
 223 }
 224
 225 static int sis5595_transaction(struct i2c_adapter *adap)
 226 {
 227         int temp;
 228         int result = 0;
 229         int timeout = 0;
 230
 231         /* Make sure the SMBus host is ready to start transmitting */
 232         temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8);
 233         if (temp != 0x00) {
 234                 dev_dbg(&adap->dev, "SMBus busy (%04x). Resetting...\n", temp);
 235                 sis5595_write(SMB_STS_LO, temp & 0xff);
 236                 sis5595_write(SMB_STS_HI, temp >> 8);
 237                 if ((temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8)) != 0x00) {
 238                         dev_dbg(&adap->dev, "Failed! (%02x)\n", temp);
 239                         return -EBUSY;
 240                 } else {
 241                         dev_dbg(&adap->dev, "Successful!\n");
 242                 }
 243         }
 244
 245         /* start the transaction by setting bit 4 */
 246         sis5595_write(SMB_CTL_LO, sis5595_read(SMB_CTL_LO) | 0x10);
 247
 248         /* We will always wait for a fraction of a second! */
 249         do {
 250                 msleep(1);
 251                 temp = sis5595_read(SMB_STS_LO);
 252         } while (!(temp & 0x40) && (timeout++ < MAX_TIMEOUT));
 253
 254         /* If the SMBus is still busy, we give up */
 255         if (timeout > MAX_TIMEOUT) {
 256                 dev_dbg(&adap->dev, "SMBus Timeout!\n");
 257                 result = -ETIMEDOUT;
 258         }
 259
 260         if (temp & 0x10) {
 261                 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
 262                 result = -ENXIO;
 263         }
 264
 265         if (temp & 0x20) {
 266                 dev_err(&adap->dev, "Bus collision! SMBus may be locked until "
 267                         "next hard reset (or not...)\n");
 268                 /* Clock stops and slave is stuck in mid-transmission */
 269                 result = -EIO;
 270         }
 271
 272         temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8);
 273         if (temp != 0x00) {
 274                 sis5595_write(SMB_STS_LO, temp & 0xff);
 275                 sis5595_write(SMB_STS_HI, temp >> 8);
 276         }
 277
 278         temp = sis5595_read(SMB_STS_LO) + (sis5595_read(SMB_STS_HI) << 8);
 279         if (temp != 0x00)
 280                 dev_dbg(&adap->dev, "Failed reset at end of transaction (%02x)\n", temp);
 281
 282         return result;
 283 }
 284
 285 /* Return negative errno on error. */
 286 static s32 sis5595_access(struct i2c_adapter *adap, u16 addr,
 287                           unsigned short flags, char read_write,
 288                           u8 command, int size, union i2c_smbus_data *data)
 289 {
 290         int status;
 291
 292         switch (size) {
 293         case I2C_SMBUS_QUICK:
 294                 sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
 295                 size = SIS5595_QUICK;
 296                 break;
 297         case I2C_SMBUS_BYTE:
 298                 sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
 299                 if (read_write == I2C_SMBUS_WRITE)
 300                         sis5595_write(SMB_CMD, command);
 301                 size = SIS5595_BYTE;
 302                 break;
 303         case I2C_SMBUS_BYTE_DATA:
 304                 sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
 305                 sis5595_write(SMB_CMD, command);
 306                 if (read_write == I2C_SMBUS_WRITE)
 307                         sis5595_write(SMB_BYTE, data->byte);
 308                 size = SIS5595_BYTE_DATA;
 309                 break;
 310         case I2C_SMBUS_PROC_CALL:
 311         case I2C_SMBUS_WORD_DATA:
 312                 sis5595_write(SMB_ADDR, ((addr & 0x7f) << 1) | (read_write & 0x01));
 313                 sis5595_write(SMB_CMD, command);
 314                 if (read_write == I2C_SMBUS_WRITE) {
 315                         sis5595_write(SMB_BYTE, data->word & 0xff);
 316                         sis5595_write(SMB_BYTE + 1,
 317                                       (data->word & 0xff00) >> 8);
 318                 }
 319                 size = (size == I2C_SMBUS_PROC_CALL) ? SIS5595_PROC_CALL : SIS5595_WORD_DATA;
 320                 break;
 321         default:
 322                 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
 323                 return -EOPNOTSUPP;
 324         }
 325
 326         sis5595_write(SMB_CTL_LO, ((size & 0x0E)));
 327
 328         status = sis5595_transaction(adap);
 329         if (status)
 330                 return status;
 331
 332         if ((size != SIS5595_PROC_CALL) &&
 333             ((read_write == I2C_SMBUS_WRITE) || (size == SIS5595_QUICK)))
 334                 return 0;
 335
 336
 337         switch (size) {
 338         case SIS5595_BYTE:
 339         case SIS5595_BYTE_DATA:
 340                 data->byte = sis5595_read(SMB_BYTE);
 341                 break;
 342         case SIS5595_WORD_DATA:
 343         case SIS5595_PROC_CALL:
 344                 data->word = sis5595_read(SMB_BYTE) + (sis5595_read(SMB_BYTE + 1) << 8);
 345                 break;
 346         }
 347         return 0;
 348 }
 349
 350 static u32 sis5595_func(struct i2c_adapter *adapter)
 351 {
 352         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 353             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 354             I2C_FUNC_SMBUS_PROC_CALL;
 355 }
 356
 357 static const struct i2c_algorithm smbus_algorithm = {
 358         .smbus_xfer     = sis5595_access,
 359         .functionality  = sis5595_func,
 360 };
 361
 362 static struct i2c_adapter sis5595_adapter = {
 363         .owner          = THIS_MODULE,
 364         .class          = I2C_CLASS_HWMON | I2C_CLASS_SPD,
 365         .algo           = &smbus_algorithm,
 366 };
 367
 368 static const struct pci_device_id sis5595_ids[] = {
 369         { PCI_DEVICE(PCI_VENDOR_ID_SI, PCI_DEVICE_ID_SI_503) },
 370         { 0, }
 371 };
 372
 373 MODULE_DEVICE_TABLE (pci, sis5595_ids);
 374
 375 static int sis5595_probe(struct pci_dev *dev, const struct pci_device_id *id)
 376 {
 377         int err;
 378
 379         if (sis5595_setup(dev)) {
 380                 dev_err(&dev->dev, "SIS5595 not detected, module not inserted.\n");
 381                 return -ENODEV;
 382         }
 383
 384         /* set up the sysfs linkage to our parent device */
 385         sis5595_adapter.dev.parent = &dev->dev;
 386
 387         snprintf(sis5595_adapter.name, sizeof(sis5595_adapter.name),
 388                  "SMBus SIS5595 adapter at %04x", sis5595_base + SMB_INDEX);
 389         err = i2c_add_adapter(&sis5595_adapter);
 390         if (err) {
 391                 release_region(sis5595_base + SMB_INDEX, 2);
 392                 return err;
 393         }
 394
 395         /* Always return failure here.  This is to allow other drivers to bind
 396          * to this pci device.  We don't really want to have control over the
 397          * pci device, we only wanted to read as few register values from it.
 398          */
 399         sis5595_pdev =  pci_dev_get(dev);
 400         return -ENODEV;
 401 }
 402
 403 static struct pci_driver sis5595_driver = {
 404         .name           = "sis5595_smbus",
 405         .id_table       = sis5595_ids,
 406         .probe          = sis5595_probe,
 407 };
 408
 409 static int __init i2c_sis5595_init(void)
 410 {
 411         return pci_register_driver(&sis5595_driver);
 412 }
 413
 414 static void __exit i2c_sis5595_exit(void)
 415 {
 416         pci_unregister_driver(&sis5595_driver);
 417         if (sis5595_pdev) {
 418                 i2c_del_adapter(&sis5595_adapter);
 419                 release_region(sis5595_base + SMB_INDEX, 2);
 420                 pci_dev_put(sis5595_pdev);
 421                 sis5595_pdev = NULL;
 422         }
 423 }
 424
 425 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>");
 426 MODULE_DESCRIPTION("SIS5595 SMBus driver");
 427 MODULE_LICENSE("GPL");
 428
 429 module_init(i2c_sis5595_init);
 430 module_exit(i2c_sis5595_exit);