drivers/i2c/busses/i2c-ali15x3.c

   1 /*
   2     Copyright (c) 1999  Frodo Looijaard <frodol@dds.nl> and
   3     Philip Edelbrock <phil@netroedge.com> and
   4     Mark D. Studebaker <mdsxyz123@yahoo.com>
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  19 */
  20
  21 /*
  22     This is the driver for the SMB Host controller on
  23     Acer Labs Inc. (ALI) M1541 and M1543C South Bridges.
  24
  25     The M1543C is a South bridge for desktop systems.
  26     The M1533 is a South bridge for portable systems.
  27     They are part of the following ALI chipsets:
  28        "Aladdin Pro 2": Includes the M1621 Slot 1 North bridge
  29        with AGP and 100MHz CPU Front Side bus
  30        "Aladdin V": Includes the M1541 Socket 7 North bridge
  31        with AGP and 100MHz CPU Front Side bus
  32        "Aladdin IV": Includes the M1541 Socket 7 North bridge
  33        with host bus up to 83.3 MHz.
  34     For an overview of these chips see http://www.acerlabs.com
  35
  36     The M1533/M1543C devices appear as FOUR separate devices
  37     on the PCI bus. An output of lspci will show something similar
  38     to the following:
  39
  40         00:02.0 USB Controller: Acer Laboratories Inc. M5237
  41         00:03.0 Bridge: Acer Laboratories Inc. M7101
  42         00:07.0 ISA bridge: Acer Laboratories Inc. M1533
  43         00:0f.0 IDE interface: Acer Laboratories Inc. M5229
  44
  45     The SMB controller is part of the 7101 device, which is an
  46     ACPI-compliant Power Management Unit (PMU).
  47
  48     The whole 7101 device has to be enabled for the SMB to work.
  49     You can't just enable the SMB alone.
  50     The SMB and the ACPI have separate I/O spaces.
  51     We make sure that the SMB is enabled. We leave the ACPI alone.
  52
  53     This driver controls the SMB Host only.
  54     The SMB Slave controller on the M15X3 is not enabled.
  55
  56     This driver does not use interrupts.
  57 */
  58
  59 /* Note: we assume there can only be one ALI15X3, with one SMBus interface */
  60
  61 #include <linux/module.h>
  62 #include <linux/pci.h>
  63 #include <linux/kernel.h>
  64 #include <linux/stddef.h>
  65 #include <linux/ioport.h>
  66 #include <linux/delay.h>
  67 #include <linux/i2c.h>
  68 #include <linux/init.h>
  69 #include <linux/acpi.h>
  70 #include <linux/io.h>
  71
  72 /* ALI15X3 SMBus address offsets */
  73 #define SMBHSTSTS       (0 + ali15x3_smba)
  74 #define SMBHSTCNT       (1 + ali15x3_smba)
  75 #define SMBHSTSTART     (2 + ali15x3_smba)
  76 #define SMBHSTCMD       (7 + ali15x3_smba)
  77 #define SMBHSTADD       (3 + ali15x3_smba)
  78 #define SMBHSTDAT0      (4 + ali15x3_smba)
  79 #define SMBHSTDAT1      (5 + ali15x3_smba)
  80 #define SMBBLKDAT       (6 + ali15x3_smba)
  81
  82 /* PCI Address Constants */
  83 #define SMBCOM          0x004
  84 #define SMBBA           0x014
  85 #define SMBATPC         0x05B   /* used to unlock xxxBA registers */
  86 #define SMBHSTCFG       0x0E0
  87 #define SMBSLVC         0x0E1
  88 #define SMBCLK          0x0E2
  89 #define SMBREV          0x008
  90
  91 /* Other settings */
  92 #define MAX_TIMEOUT             200     /* times 1/100 sec */
  93 #define ALI15X3_SMB_IOSIZE      32
  94
  95 /* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB.
  96    We don't use these here. If the bases aren't set to some value we
  97    tell user to upgrade BIOS and we fail.
  98 */
  99 #define ALI15X3_SMB_DEFAULTBASE 0xE800
 100
 101 /* ALI15X3 address lock bits */
 102 #define ALI15X3_LOCK            0x06
 103
 104 /* ALI15X3 command constants */
 105 #define ALI15X3_ABORT           0x02
 106 #define ALI15X3_T_OUT           0x04
 107 #define ALI15X3_QUICK           0x00
 108 #define ALI15X3_BYTE            0x10
 109 #define ALI15X3_BYTE_DATA       0x20
 110 #define ALI15X3_WORD_DATA       0x30
 111 #define ALI15X3_BLOCK_DATA      0x40
 112 #define ALI15X3_BLOCK_CLR       0x80
 113
 114 /* ALI15X3 status register bits */
 115 #define ALI15X3_STS_IDLE        0x04
 116 #define ALI15X3_STS_BUSY        0x08
 117 #define ALI15X3_STS_DONE        0x10
 118 #define ALI15X3_STS_DEV         0x20    /* device error */
 119 #define ALI15X3_STS_COLL        0x40    /* collision or no response */
 120 #define ALI15X3_STS_TERM        0x80    /* terminated by abort */
 121 #define ALI15X3_STS_ERR         0xE0    /* all the bad error bits */
 122
 123
 124 /* If force_addr is set to anything different from 0, we forcibly enable
 125    the device at the given address. */
 126 static u16 force_addr;
 127 module_param(force_addr, ushort, 0);
 128 MODULE_PARM_DESC(force_addr,
 129                  "Initialize the base address of the i2c controller");
 130
 131 static struct pci_driver ali15x3_driver;
 132 static unsigned short ali15x3_smba;
 133
 134 static int __devinit ali15x3_setup(struct pci_dev *ALI15X3_dev)
 135 {
 136         u16 a;
 137         unsigned char temp;
 138
 139         /* Check the following things:
 140                 - SMB I/O address is initialized
 141                 - Device is enabled
 142                 - We can use the addresses
 143         */
 144
 145         /* Unlock the register.
 146            The data sheet says that the address registers are read-only
 147            if the lock bits are 1, but in fact the address registers
 148            are zero unless you clear the lock bits.
 149         */
 150         pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp);
 151         if (temp & ALI15X3_LOCK) {
 152                 temp &= ~ALI15X3_LOCK;
 153                 pci_write_config_byte(ALI15X3_dev, SMBATPC, temp);
 154         }
 155
 156         /* Determine the address of the SMBus area */
 157         pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba);
 158         ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1));
 159         if (ali15x3_smba == 0 && force_addr == 0) {
 160                 dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized "
 161                         "- upgrade BIOS or use force_addr=0xaddr\n");
 162                 return -ENODEV;
 163         }
 164
 165         if(force_addr)
 166                 ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1);
 167
 168         if (acpi_check_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
 169                               ali15x3_driver.name))
 170                 return -EBUSY;
 171
 172         if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
 173                             ali15x3_driver.name)) {
 174                 dev_err(&ALI15X3_dev->dev,
 175                         "ALI15X3_smb region 0x%x already in use!\n",
 176                         ali15x3_smba);
 177                 return -ENODEV;
 178         }
 179
 180         if(force_addr) {
 181                 dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n",
 182                         ali15x3_smba);
 183                 if (PCIBIOS_SUCCESSFUL != pci_write_config_word(ALI15X3_dev,
 184                                                                 SMBBA,
 185                                                                 ali15x3_smba))
 186                         goto error;
 187                 if (PCIBIOS_SUCCESSFUL != pci_read_config_word(ALI15X3_dev,
 188                                                                 SMBBA, &a))
 189                         goto error;
 190                 if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) {
 191                         /* make sure it works */
 192                         dev_err(&ALI15X3_dev->dev,
 193                                 "force address failed - not supported?\n");
 194                         goto error;
 195                 }
 196         }
 197         /* check if whole device is enabled */
 198         pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp);
 199         if ((temp & 1) == 0) {
 200                 dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n");
 201                 pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01);
 202         }
 203
 204         /* Is SMB Host controller enabled? */
 205         pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp);
 206         if ((temp & 1) == 0) {
 207                 dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n");
 208                 pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01);
 209         }
 210
 211         /* set SMB clock to 74KHz as recommended in data sheet */
 212         pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20);
 213
 214         /*
 215           The interrupt routing for SMB is set up in register 0x77 in the
 216           1533 ISA Bridge device, NOT in the 7101 device.
 217           Don't bother with finding the 1533 device and reading the register.
 218         if ((....... & 0x0F) == 1)
 219                 dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n");
 220         */
 221         pci_read_config_byte(ALI15X3_dev, SMBREV, &temp);
 222         dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp);
 223         dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba);
 224
 225         return 0;
 226 error:
 227         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 228         return -ENODEV;
 229 }
 230
 231 /* Another internally used function */
 232 static int ali15x3_transaction(struct i2c_adapter *adap)
 233 {
 234         int temp;
 235         int result = 0;
 236         int timeout = 0;
 237
 238         dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, "
 239                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 240                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 241                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 242
 243         /* get status */
 244         temp = inb_p(SMBHSTSTS);
 245
 246         /* Make sure the SMBus host is ready to start transmitting */
 247         /* Check the busy bit first */
 248         if (temp & ALI15X3_STS_BUSY) {
 249         /*
 250            If the host controller is still busy, it may have timed out in the
 251            previous transaction, resulting in a "SMBus Timeout" Dev.
 252            I've tried the following to reset a stuck busy bit.
 253                 1. Reset the controller with an ABORT command.
 254                    (this doesn't seem to clear the controller if an external
 255                    device is hung)
 256                 2. Reset the controller and the other SMBus devices with a
 257                    T_OUT command.  (this clears the host busy bit if an
 258                    external device is hung, but it comes back upon a new access
 259                    to a device)
 260                 3. Disable and reenable the controller in SMBHSTCFG
 261            Worst case, nothing seems to work except power reset.
 262         */
 263         /* Abort - reset the host controller */
 264         /*
 265            Try resetting entire SMB bus, including other devices -
 266            This may not work either - it clears the BUSY bit but
 267            then the BUSY bit may come back on when you try and use the chip again.
 268            If that's the case you are stuck.
 269         */
 270                 dev_info(&adap->dev, "Resetting entire SMB Bus to "
 271                         "clear busy condition (%02x)\n", temp);
 272                 outb_p(ALI15X3_T_OUT, SMBHSTCNT);
 273                 temp = inb_p(SMBHSTSTS);
 274         }
 275
 276         /* now check the error bits and the busy bit */
 277         if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 278                 /* do a clear-on-write */
 279                 outb_p(0xFF, SMBHSTSTS);
 280                 if ((temp = inb_p(SMBHSTSTS)) &
 281                     (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 282                         /* this is probably going to be correctable only by a power reset
 283                            as one of the bits now appears to be stuck */
 284                         /* This may be a bus or device with electrical problems. */
 285                         dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
 286                                 "controller or device on bus is probably hung\n",
 287                                 temp);
 288                         return -EBUSY;
 289                 }
 290         } else {
 291                 /* check and clear done bit */
 292                 if (temp & ALI15X3_STS_DONE) {
 293                         outb_p(temp, SMBHSTSTS);
 294                 }
 295         }
 296
 297         /* start the transaction by writing anything to the start register */
 298         outb_p(0xFF, SMBHSTSTART);
 299
 300         /* We will always wait for a fraction of a second! */
 301         timeout = 0;
 302         do {
 303                 msleep(1);
 304                 temp = inb_p(SMBHSTSTS);
 305         } while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
 306                  && (timeout++ < MAX_TIMEOUT));
 307
 308         /* If the SMBus is still busy, we give up */
 309         if (timeout > MAX_TIMEOUT) {
 310                 result = -ETIMEDOUT;
 311                 dev_err(&adap->dev, "SMBus Timeout!\n");
 312         }
 313
 314         if (temp & ALI15X3_STS_TERM) {
 315                 result = -EIO;
 316                 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
 317         }
 318
 319         /*
 320           Unfortunately the ALI SMB controller maps "no response" and "bus
 321           collision" into a single bit. No response is the usual case so don't
 322           do a printk.
 323           This means that bus collisions go unreported.
 324         */
 325         if (temp & ALI15X3_STS_COLL) {
 326                 result = -ENXIO;
 327                 dev_dbg(&adap->dev,
 328                         "Error: no response or bus collision ADD=%02x\n",
 329                         inb_p(SMBHSTADD));
 330         }
 331
 332         /* haven't ever seen this */
 333         if (temp & ALI15X3_STS_DEV) {
 334                 result = -EIO;
 335                 dev_err(&adap->dev, "Error: device error\n");
 336         }
 337         dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
 338                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 339                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 340                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 341         return result;
 342 }
 343
 344 /* Return negative errno on error. */
 345 static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr,
 346                    unsigned short flags, char read_write, u8 command,
 347                    int size, union i2c_smbus_data * data)
 348 {
 349         int i, len;
 350         int temp;
 351         int timeout;
 352
 353         /* clear all the bits (clear-on-write) */
 354         outb_p(0xFF, SMBHSTSTS);
 355         /* make sure SMBus is idle */
 356         temp = inb_p(SMBHSTSTS);
 357         for (timeout = 0;
 358              (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
 359              timeout++) {
 360                 msleep(1);
 361                 temp = inb_p(SMBHSTSTS);
 362         }
 363         if (timeout >= MAX_TIMEOUT) {
 364                 dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
 365         }
 366
 367         switch (size) {
 368         case I2C_SMBUS_QUICK:
 369                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 370                        SMBHSTADD);
 371                 size = ALI15X3_QUICK;
 372                 break;
 373         case I2C_SMBUS_BYTE:
 374                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 375                        SMBHSTADD);
 376                 if (read_write == I2C_SMBUS_WRITE)
 377                         outb_p(command, SMBHSTCMD);
 378                 size = ALI15X3_BYTE;
 379                 break;
 380         case I2C_SMBUS_BYTE_DATA:
 381                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 382                        SMBHSTADD);
 383                 outb_p(command, SMBHSTCMD);
 384                 if (read_write == I2C_SMBUS_WRITE)
 385                         outb_p(data->byte, SMBHSTDAT0);
 386                 size = ALI15X3_BYTE_DATA;
 387                 break;
 388         case I2C_SMBUS_WORD_DATA:
 389                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 390                        SMBHSTADD);
 391                 outb_p(command, SMBHSTCMD);
 392                 if (read_write == I2C_SMBUS_WRITE) {
 393                         outb_p(data->word & 0xff, SMBHSTDAT0);
 394                         outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
 395                 }
 396                 size = ALI15X3_WORD_DATA;
 397                 break;
 398         case I2C_SMBUS_BLOCK_DATA:
 399                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 400                        SMBHSTADD);
 401                 outb_p(command, SMBHSTCMD);
 402                 if (read_write == I2C_SMBUS_WRITE) {
 403                         len = data->block[0];
 404                         if (len < 0) {
 405                                 len = 0;
 406                                 data->block[0] = len;
 407                         }
 408                         if (len > 32) {
 409                                 len = 32;
 410                                 data->block[0] = len;
 411                         }
 412                         outb_p(len, SMBHSTDAT0);
 413                         /* Reset SMBBLKDAT */
 414                         outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 415                         for (i = 1; i <= len; i++)
 416                                 outb_p(data->block[i], SMBBLKDAT);
 417                 }
 418                 size = ALI15X3_BLOCK_DATA;
 419                 break;
 420         default:
 421                 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
 422                 return -EOPNOTSUPP;
 423         }
 424
 425         outb_p(size, SMBHSTCNT);        /* output command */
 426
 427         temp = ali15x3_transaction(adap);
 428         if (temp)
 429                 return temp;
 430
 431         if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
 432                 return 0;
 433
 434
 435         switch (size) {
 436         case ALI15X3_BYTE:      /* Result put in SMBHSTDAT0 */
 437                 data->byte = inb_p(SMBHSTDAT0);
 438                 break;
 439         case ALI15X3_BYTE_DATA:
 440                 data->byte = inb_p(SMBHSTDAT0);
 441                 break;
 442         case ALI15X3_WORD_DATA:
 443                 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
 444                 break;
 445         case ALI15X3_BLOCK_DATA:
 446                 len = inb_p(SMBHSTDAT0);
 447                 if (len > 32)
 448                         len = 32;
 449                 data->block[0] = len;
 450                 /* Reset SMBBLKDAT */
 451                 outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 452                 for (i = 1; i <= data->block[0]; i++) {
 453                         data->block[i] = inb_p(SMBBLKDAT);
 454                         dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
 455                                 len, i, data->block[i]);
 456                 }
 457                 break;
 458         }
 459         return 0;
 460 }
 461
 462 static u32 ali15x3_func(struct i2c_adapter *adapter)
 463 {
 464         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 465             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 466             I2C_FUNC_SMBUS_BLOCK_DATA;
 467 }
 468
 469 static const struct i2c_algorithm smbus_algorithm = {
 470         .smbus_xfer     = ali15x3_access,
 471         .functionality  = ali15x3_func,
 472 };
 473
 474 static struct i2c_adapter ali15x3_adapter = {
 475         .owner          = THIS_MODULE,
 476         .class          = I2C_CLASS_HWMON | I2C_CLASS_SPD,
 477         .algo           = &smbus_algorithm,
 478 };
 479
 480 static DEFINE_PCI_DEVICE_TABLE(ali15x3_ids) = {
 481         { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
 482         { 0, }
 483 };
 484
 485 MODULE_DEVICE_TABLE (pci, ali15x3_ids);
 486
 487 static int __devinit ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id)
 488 {
 489         if (ali15x3_setup(dev)) {
 490                 dev_err(&dev->dev,
 491                         "ALI15X3 not detected, module not inserted.\n");
 492                 return -ENODEV;
 493         }
 494
 495         /* set up the sysfs linkage to our parent device */
 496         ali15x3_adapter.dev.parent = &dev->dev;
 497
 498         snprintf(ali15x3_adapter.name, sizeof(ali15x3_adapter.name),
 499                 "SMBus ALI15X3 adapter at %04x", ali15x3_smba);
 500         return i2c_add_adapter(&ali15x3_adapter);
 501 }
 502
 503 static void __devexit ali15x3_remove(struct pci_dev *dev)
 504 {
 505         i2c_del_adapter(&ali15x3_adapter);
 506         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 507 }
 508
 509 static struct pci_driver ali15x3_driver = {
 510         .name           = "ali15x3_smbus",
 511         .id_table       = ali15x3_ids,
 512         .probe          = ali15x3_probe,
 513         .remove         = __devexit_p(ali15x3_remove),
 514 };
 515
 516 static int __init i2c_ali15x3_init(void)
 517 {
 518         return pci_register_driver(&ali15x3_driver);
 519 }
 520
 521 static void __exit i2c_ali15x3_exit(void)
 522 {
 523         pci_unregister_driver(&ali15x3_driver);
 524 }
 525
 526 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
 527                 "Philip Edelbrock <phil@netroedge.com>, "
 528                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
 529 MODULE_DESCRIPTION("ALI15X3 SMBus driver");
 530 MODULE_LICENSE("GPL");
 531
 532 module_init(i2c_ali15x3_init);
 533 module_exit(i2c_ali15x3_exit);