drivers/i2c/busses/i2c-ali15x3.c

   1 /*
   2     ali15x3.c - Part of lm_sensors, Linux kernel modules for hardware
   3               monitoring
   4     Copyright (c) 1999  Frodo Looijaard <frodol@dds.nl> and
   5     Philip Edelbrock <phil@netroedge.com> and
   6     Mark D. Studebaker <mdsxyz123@yahoo.com>
   7
   8     This program is free software; you can redistribute it and/or modify
   9     it under the terms of the GNU General Public License as published by
  10     the Free Software Foundation; either version 2 of the License, or
  11     (at your option) any later version.
  12
  13     This program is distributed in the hope that it will be useful,
  14     but WITHOUT ANY WARRANTY; without even the implied warranty of
  15     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16     GNU General Public License for more details.
  17
  18     You should have received a copy of the GNU General Public License
  19     along with this program; if not, write to the Free Software
  20     Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 /*
  24     This is the driver for the SMB Host controller on
  25     Acer Labs Inc. (ALI) M1541 and M1543C South Bridges.
  26
  27     The M1543C is a South bridge for desktop systems.
  28     The M1533 is a South bridge for portable systems.
  29     They are part of the following ALI chipsets:
  30        "Aladdin Pro 2": Includes the M1621 Slot 1 North bridge
  31        with AGP and 100MHz CPU Front Side bus
  32        "Aladdin V": Includes the M1541 Socket 7 North bridge
  33        with AGP and 100MHz CPU Front Side bus
  34        "Aladdin IV": Includes the M1541 Socket 7 North bridge
  35        with host bus up to 83.3 MHz.
  36     For an overview of these chips see http://www.acerlabs.com
  37
  38     The M1533/M1543C devices appear as FOUR separate devices
  39     on the PCI bus. An output of lspci will show something similar
  40     to the following:
  41
  42         00:02.0 USB Controller: Acer Laboratories Inc. M5237
  43         00:03.0 Bridge: Acer Laboratories Inc. M7101
  44         00:07.0 ISA bridge: Acer Laboratories Inc. M1533
  45         00:0f.0 IDE interface: Acer Laboratories Inc. M5229
  46
  47     The SMB controller is part of the 7101 device, which is an
  48     ACPI-compliant Power Management Unit (PMU).
  49
  50     The whole 7101 device has to be enabled for the SMB to work.
  51     You can't just enable the SMB alone.
  52     The SMB and the ACPI have separate I/O spaces.
  53     We make sure that the SMB is enabled. We leave the ACPI alone.
  54
  55     This driver controls the SMB Host only.
  56     The SMB Slave controller on the M15X3 is not enabled.
  57
  58     This driver does not use interrupts.
  59 */
  60
  61 /* Note: we assume there can only be one ALI15X3, with one SMBus interface */
  62
  63 #include <linux/config.h>
  64 #include <linux/module.h>
  65 #include <linux/pci.h>
  66 #include <linux/kernel.h>
  67 #include <linux/stddef.h>
  68 #include <linux/sched.h>
  69 #include <linux/ioport.h>
  70 #include <linux/delay.h>
  71 #include <linux/i2c.h>
  72 #include <linux/init.h>
  73 #include <asm/io.h>
  74
  75 /* ALI15X3 SMBus address offsets */
  76 #define SMBHSTSTS       (0 + ali15x3_smba)
  77 #define SMBHSTCNT       (1 + ali15x3_smba)
  78 #define SMBHSTSTART     (2 + ali15x3_smba)
  79 #define SMBHSTCMD       (7 + ali15x3_smba)
  80 #define SMBHSTADD       (3 + ali15x3_smba)
  81 #define SMBHSTDAT0      (4 + ali15x3_smba)
  82 #define SMBHSTDAT1      (5 + ali15x3_smba)
  83 #define SMBBLKDAT       (6 + ali15x3_smba)
  84
  85 /* PCI Address Constants */
  86 #define SMBCOM          0x004
  87 #define SMBBA           0x014
  88 #define SMBATPC         0x05B   /* used to unlock xxxBA registers */
  89 #define SMBHSTCFG       0x0E0
  90 #define SMBSLVC         0x0E1
  91 #define SMBCLK          0x0E2
  92 #define SMBREV          0x008
  93
  94 /* Other settings */
  95 #define MAX_TIMEOUT             200     /* times 1/100 sec */
  96 #define ALI15X3_SMB_IOSIZE      32
  97
  98 /* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB.
  99    We don't use these here. If the bases aren't set to some value we
 100    tell user to upgrade BIOS and we fail.
 101 */
 102 #define ALI15X3_SMB_DEFAULTBASE 0xE800
 103
 104 /* ALI15X3 address lock bits */
 105 #define ALI15X3_LOCK            0x06
 106
 107 /* ALI15X3 command constants */
 108 #define ALI15X3_ABORT           0x02
 109 #define ALI15X3_T_OUT           0x04
 110 #define ALI15X3_QUICK           0x00
 111 #define ALI15X3_BYTE            0x10
 112 #define ALI15X3_BYTE_DATA       0x20
 113 #define ALI15X3_WORD_DATA       0x30
 114 #define ALI15X3_BLOCK_DATA      0x40
 115 #define ALI15X3_BLOCK_CLR       0x80
 116
 117 /* ALI15X3 status register bits */
 118 #define ALI15X3_STS_IDLE        0x04
 119 #define ALI15X3_STS_BUSY        0x08
 120 #define ALI15X3_STS_DONE        0x10
 121 #define ALI15X3_STS_DEV         0x20    /* device error */
 122 #define ALI15X3_STS_COLL        0x40    /* collision or no response */
 123 #define ALI15X3_STS_TERM        0x80    /* terminated by abort */
 124 #define ALI15X3_STS_ERR         0xE0    /* all the bad error bits */
 125
 126
 127 /* If force_addr is set to anything different from 0, we forcibly enable
 128    the device at the given address. */
 129 static u16 force_addr = 0;
 130 module_param(force_addr, ushort, 0);
 131 MODULE_PARM_DESC(force_addr,
 132                  "Initialize the base address of the i2c controller");
 133
 134 static unsigned short ali15x3_smba = 0;
 135
 136 static int ali15x3_setup(struct pci_dev *ALI15X3_dev)
 137 {
 138         u16 a;
 139         unsigned char temp;
 140
 141         /* Check the following things:
 142                 - SMB I/O address is initialized
 143                 - Device is enabled
 144                 - We can use the addresses
 145         */
 146
 147         /* Unlock the register.
 148            The data sheet says that the address registers are read-only
 149            if the lock bits are 1, but in fact the address registers
 150            are zero unless you clear the lock bits.
 151         */
 152         pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp);
 153         if (temp & ALI15X3_LOCK) {
 154                 temp &= ~ALI15X3_LOCK;
 155                 pci_write_config_byte(ALI15X3_dev, SMBATPC, temp);
 156         }
 157
 158         /* Determine the address of the SMBus area */
 159         pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba);
 160         ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1));
 161         if (ali15x3_smba == 0 && force_addr == 0) {
 162                 dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized "
 163                         "- upgrade BIOS or use force_addr=0xaddr\n");
 164                 return -ENODEV;
 165         }
 166
 167         if(force_addr)
 168                 ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1);
 169
 170         if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE, "ali15x3-smb")) {
 171                 dev_err(&ALI15X3_dev->dev,
 172                         "ALI15X3_smb region 0x%x already in use!\n",
 173                         ali15x3_smba);
 174                 return -ENODEV;
 175         }
 176
 177         if(force_addr) {
 178                 dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n",
 179                         ali15x3_smba);
 180                 if (PCIBIOS_SUCCESSFUL != pci_write_config_word(ALI15X3_dev,
 181                                                                 SMBBA,
 182                                                                 ali15x3_smba))
 183                         goto error;
 184                 if (PCIBIOS_SUCCESSFUL != pci_read_config_word(ALI15X3_dev,
 185                                                                 SMBBA, &a))
 186                         goto error;
 187                 if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) {
 188                         /* make sure it works */
 189                         dev_err(&ALI15X3_dev->dev,
 190                                 "force address failed - not supported?\n");
 191                         goto error;
 192                 }
 193         }
 194         /* check if whole device is enabled */
 195         pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp);
 196         if ((temp & 1) == 0) {
 197                 dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n");
 198                 pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01);
 199         }
 200
 201         /* Is SMB Host controller enabled? */
 202         pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp);
 203         if ((temp & 1) == 0) {
 204                 dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n");
 205                 pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01);
 206         }
 207
 208         /* set SMB clock to 74KHz as recommended in data sheet */
 209         pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20);
 210
 211         /*
 212           The interrupt routing for SMB is set up in register 0x77 in the
 213           1533 ISA Bridge device, NOT in the 7101 device.
 214           Don't bother with finding the 1533 device and reading the register.
 215         if ((....... & 0x0F) == 1)
 216                 dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n");
 217         */
 218         pci_read_config_byte(ALI15X3_dev, SMBREV, &temp);
 219         dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp);
 220         dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba);
 221
 222         return 0;
 223 error:
 224         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 225         return -ENODEV;
 226 }
 227
 228 /* Another internally used function */
 229 static int ali15x3_transaction(struct i2c_adapter *adap)
 230 {
 231         int temp;
 232         int result = 0;
 233         int timeout = 0;
 234
 235         dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, "
 236                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 237                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 238                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 239
 240         /* get status */
 241         temp = inb_p(SMBHSTSTS);
 242
 243         /* Make sure the SMBus host is ready to start transmitting */
 244         /* Check the busy bit first */
 245         if (temp & ALI15X3_STS_BUSY) {
 246         /*
 247            If the host controller is still busy, it may have timed out in the
 248            previous transaction, resulting in a "SMBus Timeout" Dev.
 249            I've tried the following to reset a stuck busy bit.
 250                 1. Reset the controller with an ABORT command.
 251                    (this doesn't seem to clear the controller if an external
 252                    device is hung)
 253                 2. Reset the controller and the other SMBus devices with a
 254                    T_OUT command.  (this clears the host busy bit if an
 255                    external device is hung, but it comes back upon a new access
 256                    to a device)
 257                 3. Disable and reenable the controller in SMBHSTCFG
 258            Worst case, nothing seems to work except power reset.
 259         */
 260         /* Abort - reset the host controller */
 261         /*
 262            Try resetting entire SMB bus, including other devices -
 263            This may not work either - it clears the BUSY bit but
 264            then the BUSY bit may come back on when you try and use the chip again.
 265            If that's the case you are stuck.
 266         */
 267                 dev_info(&adap->dev, "Resetting entire SMB Bus to "
 268                         "clear busy condition (%02x)\n", temp);
 269                 outb_p(ALI15X3_T_OUT, SMBHSTCNT);
 270                 temp = inb_p(SMBHSTSTS);
 271         }
 272
 273         /* now check the error bits and the busy bit */
 274         if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 275                 /* do a clear-on-write */
 276                 outb_p(0xFF, SMBHSTSTS);
 277                 if ((temp = inb_p(SMBHSTSTS)) &
 278                     (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 279                         /* this is probably going to be correctable only by a power reset
 280                            as one of the bits now appears to be stuck */
 281                         /* This may be a bus or device with electrical problems. */
 282                         dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
 283                                 "controller or device on bus is probably hung\n",
 284                                 temp);
 285                         return -1;
 286                 }
 287         } else {
 288                 /* check and clear done bit */
 289                 if (temp & ALI15X3_STS_DONE) {
 290                         outb_p(temp, SMBHSTSTS);
 291                 }
 292         }
 293
 294         /* start the transaction by writing anything to the start register */
 295         outb_p(0xFF, SMBHSTSTART);
 296
 297         /* We will always wait for a fraction of a second! */
 298         timeout = 0;
 299         do {
 300                 msleep(1);
 301                 temp = inb_p(SMBHSTSTS);
 302         } while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
 303                  && (timeout++ < MAX_TIMEOUT));
 304
 305         /* If the SMBus is still busy, we give up */
 306         if (timeout >= MAX_TIMEOUT) {
 307                 result = -1;
 308                 dev_err(&adap->dev, "SMBus Timeout!\n");
 309         }
 310
 311         if (temp & ALI15X3_STS_TERM) {
 312                 result = -1;
 313                 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
 314         }
 315
 316         /*
 317           Unfortunately the ALI SMB controller maps "no response" and "bus
 318           collision" into a single bit. No reponse is the usual case so don't
 319           do a printk.
 320           This means that bus collisions go unreported.
 321         */
 322         if (temp & ALI15X3_STS_COLL) {
 323                 result = -1;
 324                 dev_dbg(&adap->dev,
 325                         "Error: no response or bus collision ADD=%02x\n",
 326                         inb_p(SMBHSTADD));
 327         }
 328
 329         /* haven't ever seen this */
 330         if (temp & ALI15X3_STS_DEV) {
 331                 result = -1;
 332                 dev_err(&adap->dev, "Error: device error\n");
 333         }
 334         dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
 335                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 336                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 337                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 338         return result;
 339 }
 340
 341 /* Return -1 on error. */
 342 static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr,
 343                    unsigned short flags, char read_write, u8 command,
 344                    int size, union i2c_smbus_data * data)
 345 {
 346         int i, len;
 347         int temp;
 348         int timeout;
 349
 350         /* clear all the bits (clear-on-write) */
 351         outb_p(0xFF, SMBHSTSTS);
 352         /* make sure SMBus is idle */
 353         temp = inb_p(SMBHSTSTS);
 354         for (timeout = 0;
 355              (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
 356              timeout++) {
 357                 msleep(1);
 358                 temp = inb_p(SMBHSTSTS);
 359         }
 360         if (timeout >= MAX_TIMEOUT) {
 361                 dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
 362         }
 363
 364         switch (size) {
 365         case I2C_SMBUS_PROC_CALL:
 366                 dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
 367                 return -1;
 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         }
 421
 422         outb_p(size, SMBHSTCNT);        /* output command */
 423
 424         if (ali15x3_transaction(adap))  /* Error in transaction */
 425                 return -1;
 426
 427         if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
 428                 return 0;
 429
 430
 431         switch (size) {
 432         case ALI15X3_BYTE:      /* Result put in SMBHSTDAT0 */
 433                 data->byte = inb_p(SMBHSTDAT0);
 434                 break;
 435         case ALI15X3_BYTE_DATA:
 436                 data->byte = inb_p(SMBHSTDAT0);
 437                 break;
 438         case ALI15X3_WORD_DATA:
 439                 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
 440                 break;
 441         case ALI15X3_BLOCK_DATA:
 442                 len = inb_p(SMBHSTDAT0);
 443                 if (len > 32)
 444                         len = 32;
 445                 data->block[0] = len;
 446                 /* Reset SMBBLKDAT */
 447                 outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 448                 for (i = 1; i <= data->block[0]; i++) {
 449                         data->block[i] = inb_p(SMBBLKDAT);
 450                         dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
 451                                 len, i, data->block[i]);
 452                 }
 453                 break;
 454         }
 455         return 0;
 456 }
 457
 458 static u32 ali15x3_func(struct i2c_adapter *adapter)
 459 {
 460         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 461             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 462             I2C_FUNC_SMBUS_BLOCK_DATA;
 463 }
 464
 465 static struct i2c_algorithm smbus_algorithm = {
 466         .name           = "Non-I2C SMBus adapter",
 467         .id             = I2C_ALGO_SMBUS,
 468         .smbus_xfer     = ali15x3_access,
 469         .functionality  = ali15x3_func,
 470 };
 471
 472 static struct i2c_adapter ali15x3_adapter = {
 473         .owner          = THIS_MODULE,
 474         .class          = I2C_CLASS_HWMON,
 475         .algo           = &smbus_algorithm,
 476         .name           = "unset",
 477 };
 478
 479 static struct pci_device_id ali15x3_ids[] = {
 480         { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) },
 481         { 0, }
 482 };
 483
 484 MODULE_DEVICE_TABLE (pci, ali15x3_ids);
 485
 486 static int __devinit ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id)
 487 {
 488         if (ali15x3_setup(dev)) {
 489                 dev_err(&dev->dev,
 490                         "ALI15X3 not detected, module not inserted.\n");
 491                 return -ENODEV;
 492         }
 493
 494         /* set up the driverfs linkage to our parent device */
 495         ali15x3_adapter.dev.parent = &dev->dev;
 496
 497         snprintf(ali15x3_adapter.name, I2C_NAME_SIZE,
 498                 "SMBus ALI15X3 adapter at %04x", ali15x3_smba);
 499         return i2c_add_adapter(&ali15x3_adapter);
 500 }
 501
 502 static void __devexit ali15x3_remove(struct pci_dev *dev)
 503 {
 504         i2c_del_adapter(&ali15x3_adapter);
 505         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 506 }
 507
 508 static struct pci_driver ali15x3_driver = {
 509         .name           = "ali15x3_smbus",
 510         .id_table       = ali15x3_ids,
 511         .probe          = ali15x3_probe,
 512         .remove         = __devexit_p(ali15x3_remove),
 513 };
 514
 515 static int __init i2c_ali15x3_init(void)
 516 {
 517         return pci_register_driver(&ali15x3_driver);
 518 }
 519
 520 static void __exit i2c_ali15x3_exit(void)
 521 {
 522         pci_unregister_driver(&ali15x3_driver);
 523 }
 524
 525 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
 526                 "Philip Edelbrock <phil@netroedge.com>, "
 527                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
 528 MODULE_DESCRIPTION("ALI15X3 SMBus driver");
 529 MODULE_LICENSE("GPL");
 530
 531 module_init(i2c_ali15x3_init);
 532 module_exit(i2c_ali15x3_exit);