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/acpi.h>
  69 #include <linux/io.h>
  70
  71 /* ALI15X3 SMBus address offsets */
  72 #define SMBHSTSTS       (0 + ali15x3_smba)
  73 #define SMBHSTCNT       (1 + ali15x3_smba)
  74 #define SMBHSTSTART     (2 + ali15x3_smba)
  75 #define SMBHSTCMD       (7 + ali15x3_smba)
  76 #define SMBHSTADD       (3 + ali15x3_smba)
  77 #define SMBHSTDAT0      (4 + ali15x3_smba)
  78 #define SMBHSTDAT1      (5 + ali15x3_smba)
  79 #define SMBBLKDAT       (6 + ali15x3_smba)
  80
  81 /* PCI Address Constants */
  82 #define SMBCOM          0x004
  83 #define SMBBA           0x014
  84 #define SMBATPC         0x05B   /* used to unlock xxxBA registers */
  85 #define SMBHSTCFG       0x0E0
  86 #define SMBSLVC         0x0E1
  87 #define SMBCLK          0x0E2
  88 #define SMBREV          0x008
  89
  90 /* Other settings */
  91 #define MAX_TIMEOUT             200     /* times 1/100 sec */
  92 #define ALI15X3_SMB_IOSIZE      32
  93
  94 /* this is what the Award 1004 BIOS sets them to on a ASUS P5A MB.
  95    We don't use these here. If the bases aren't set to some value we
  96    tell user to upgrade BIOS and we fail.
  97 */
  98 #define ALI15X3_SMB_DEFAULTBASE 0xE800
  99
 100 /* ALI15X3 address lock bits */
 101 #define ALI15X3_LOCK            0x06
 102
 103 /* ALI15X3 command constants */
 104 #define ALI15X3_ABORT           0x02
 105 #define ALI15X3_T_OUT           0x04
 106 #define ALI15X3_QUICK           0x00
 107 #define ALI15X3_BYTE            0x10
 108 #define ALI15X3_BYTE_DATA       0x20
 109 #define ALI15X3_WORD_DATA       0x30
 110 #define ALI15X3_BLOCK_DATA      0x40
 111 #define ALI15X3_BLOCK_CLR       0x80
 112
 113 /* ALI15X3 status register bits */
 114 #define ALI15X3_STS_IDLE        0x04
 115 #define ALI15X3_STS_BUSY        0x08
 116 #define ALI15X3_STS_DONE        0x10
 117 #define ALI15X3_STS_DEV         0x20    /* device error */
 118 #define ALI15X3_STS_COLL        0x40    /* collision or no response */
 119 #define ALI15X3_STS_TERM        0x80    /* terminated by abort */
 120 #define ALI15X3_STS_ERR         0xE0    /* all the bad error bits */
 121
 122
 123 /* If force_addr is set to anything different from 0, we forcibly enable
 124    the device at the given address. */
 125 static u16 force_addr;
 126 module_param(force_addr, ushort, 0);
 127 MODULE_PARM_DESC(force_addr,
 128                  "Initialize the base address of the i2c controller");
 129
 130 static struct pci_driver ali15x3_driver;
 131 static unsigned short ali15x3_smba;
 132
 133 static int ali15x3_setup(struct pci_dev *ALI15X3_dev)
 134 {
 135         u16 a;
 136         unsigned char temp;
 137
 138         /* Check the following things:
 139                 - SMB I/O address is initialized
 140                 - Device is enabled
 141                 - We can use the addresses
 142         */
 143
 144         /* Unlock the register.
 145            The data sheet says that the address registers are read-only
 146            if the lock bits are 1, but in fact the address registers
 147            are zero unless you clear the lock bits.
 148         */
 149         pci_read_config_byte(ALI15X3_dev, SMBATPC, &temp);
 150         if (temp & ALI15X3_LOCK) {
 151                 temp &= ~ALI15X3_LOCK;
 152                 pci_write_config_byte(ALI15X3_dev, SMBATPC, temp);
 153         }
 154
 155         /* Determine the address of the SMBus area */
 156         pci_read_config_word(ALI15X3_dev, SMBBA, &ali15x3_smba);
 157         ali15x3_smba &= (0xffff & ~(ALI15X3_SMB_IOSIZE - 1));
 158         if (ali15x3_smba == 0 && force_addr == 0) {
 159                 dev_err(&ALI15X3_dev->dev, "ALI15X3_smb region uninitialized "
 160                         "- upgrade BIOS or use force_addr=0xaddr\n");
 161                 return -ENODEV;
 162         }
 163
 164         if(force_addr)
 165                 ali15x3_smba = force_addr & ~(ALI15X3_SMB_IOSIZE - 1);
 166
 167         if (acpi_check_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
 168                               ali15x3_driver.name))
 169                 return -EBUSY;
 170
 171         if (!request_region(ali15x3_smba, ALI15X3_SMB_IOSIZE,
 172                             ali15x3_driver.name)) {
 173                 dev_err(&ALI15X3_dev->dev,
 174                         "ALI15X3_smb region 0x%x already in use!\n",
 175                         ali15x3_smba);
 176                 return -ENODEV;
 177         }
 178
 179         if(force_addr) {
 180                 dev_info(&ALI15X3_dev->dev, "forcing ISA address 0x%04X\n",
 181                         ali15x3_smba);
 182                 if (PCIBIOS_SUCCESSFUL != pci_write_config_word(ALI15X3_dev,
 183                                                                 SMBBA,
 184                                                                 ali15x3_smba))
 185                         goto error;
 186                 if (PCIBIOS_SUCCESSFUL != pci_read_config_word(ALI15X3_dev,
 187                                                                 SMBBA, &a))
 188                         goto error;
 189                 if ((a & ~(ALI15X3_SMB_IOSIZE - 1)) != ali15x3_smba) {
 190                         /* make sure it works */
 191                         dev_err(&ALI15X3_dev->dev,
 192                                 "force address failed - not supported?\n");
 193                         goto error;
 194                 }
 195         }
 196         /* check if whole device is enabled */
 197         pci_read_config_byte(ALI15X3_dev, SMBCOM, &temp);
 198         if ((temp & 1) == 0) {
 199                 dev_info(&ALI15X3_dev->dev, "enabling SMBus device\n");
 200                 pci_write_config_byte(ALI15X3_dev, SMBCOM, temp | 0x01);
 201         }
 202
 203         /* Is SMB Host controller enabled? */
 204         pci_read_config_byte(ALI15X3_dev, SMBHSTCFG, &temp);
 205         if ((temp & 1) == 0) {
 206                 dev_info(&ALI15X3_dev->dev, "enabling SMBus controller\n");
 207                 pci_write_config_byte(ALI15X3_dev, SMBHSTCFG, temp | 0x01);
 208         }
 209
 210         /* set SMB clock to 74KHz as recommended in data sheet */
 211         pci_write_config_byte(ALI15X3_dev, SMBCLK, 0x20);
 212
 213         /*
 214           The interrupt routing for SMB is set up in register 0x77 in the
 215           1533 ISA Bridge device, NOT in the 7101 device.
 216           Don't bother with finding the 1533 device and reading the register.
 217         if ((....... & 0x0F) == 1)
 218                 dev_dbg(&ALI15X3_dev->dev, "ALI15X3 using Interrupt 9 for SMBus.\n");
 219         */
 220         pci_read_config_byte(ALI15X3_dev, SMBREV, &temp);
 221         dev_dbg(&ALI15X3_dev->dev, "SMBREV = 0x%X\n", temp);
 222         dev_dbg(&ALI15X3_dev->dev, "iALI15X3_smba = 0x%X\n", ali15x3_smba);
 223
 224         return 0;
 225 error:
 226         release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
 227         return -ENODEV;
 228 }
 229
 230 /* Another internally used function */
 231 static int ali15x3_transaction(struct i2c_adapter *adap)
 232 {
 233         int temp;
 234         int result = 0;
 235         int timeout = 0;
 236
 237         dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, CNT=%02x, CMD=%02x, "
 238                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 239                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 240                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 241
 242         /* get status */
 243         temp = inb_p(SMBHSTSTS);
 244
 245         /* Make sure the SMBus host is ready to start transmitting */
 246         /* Check the busy bit first */
 247         if (temp & ALI15X3_STS_BUSY) {
 248         /*
 249            If the host controller is still busy, it may have timed out in the
 250            previous transaction, resulting in a "SMBus Timeout" Dev.
 251            I've tried the following to reset a stuck busy bit.
 252                 1. Reset the controller with an ABORT command.
 253                    (this doesn't seem to clear the controller if an external
 254                    device is hung)
 255                 2. Reset the controller and the other SMBus devices with a
 256                    T_OUT command.  (this clears the host busy bit if an
 257                    external device is hung, but it comes back upon a new access
 258                    to a device)
 259                 3. Disable and reenable the controller in SMBHSTCFG
 260            Worst case, nothing seems to work except power reset.
 261         */
 262         /* Abort - reset the host controller */
 263         /*
 264            Try resetting entire SMB bus, including other devices -
 265            This may not work either - it clears the BUSY bit but
 266            then the BUSY bit may come back on when you try and use the chip again.
 267            If that's the case you are stuck.
 268         */
 269                 dev_info(&adap->dev, "Resetting entire SMB Bus to "
 270                         "clear busy condition (%02x)\n", temp);
 271                 outb_p(ALI15X3_T_OUT, SMBHSTCNT);
 272                 temp = inb_p(SMBHSTSTS);
 273         }
 274
 275         /* now check the error bits and the busy bit */
 276         if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 277                 /* do a clear-on-write */
 278                 outb_p(0xFF, SMBHSTSTS);
 279                 if ((temp = inb_p(SMBHSTSTS)) &
 280                     (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
 281                         /* this is probably going to be correctable only by a power reset
 282                            as one of the bits now appears to be stuck */
 283                         /* This may be a bus or device with electrical problems. */
 284                         dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
 285                                 "controller or device on bus is probably hung\n",
 286                                 temp);
 287                         return -EBUSY;
 288                 }
 289         } else {
 290                 /* check and clear done bit */
 291                 if (temp & ALI15X3_STS_DONE) {
 292                         outb_p(temp, SMBHSTSTS);
 293                 }
 294         }
 295
 296         /* start the transaction by writing anything to the start register */
 297         outb_p(0xFF, SMBHSTSTART);
 298
 299         /* We will always wait for a fraction of a second! */
 300         timeout = 0;
 301         do {
 302                 msleep(1);
 303                 temp = inb_p(SMBHSTSTS);
 304         } while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
 305                  && (timeout++ < MAX_TIMEOUT));
 306
 307         /* If the SMBus is still busy, we give up */
 308         if (timeout > MAX_TIMEOUT) {
 309                 result = -ETIMEDOUT;
 310                 dev_err(&adap->dev, "SMBus Timeout!\n");
 311         }
 312
 313         if (temp & ALI15X3_STS_TERM) {
 314                 result = -EIO;
 315                 dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
 316         }
 317
 318         /*
 319           Unfortunately the ALI SMB controller maps "no response" and "bus
 320           collision" into a single bit. No response is the usual case so don't
 321           do a printk.
 322           This means that bus collisions go unreported.
 323         */
 324         if (temp & ALI15X3_STS_COLL) {
 325                 result = -ENXIO;
 326                 dev_dbg(&adap->dev,
 327                         "Error: no response or bus collision ADD=%02x\n",
 328                         inb_p(SMBHSTADD));
 329         }
 330
 331         /* haven't ever seen this */
 332         if (temp & ALI15X3_STS_DEV) {
 333                 result = -EIO;
 334                 dev_err(&adap->dev, "Error: device error\n");
 335         }
 336         dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
 337                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
 338                 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
 339                 inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
 340         return result;
 341 }
 342
 343 /* Return negative errno on error. */
 344 static s32 ali15x3_access(struct i2c_adapter * adap, u16 addr,
 345                    unsigned short flags, char read_write, u8 command,
 346                    int size, union i2c_smbus_data * data)
 347 {
 348         int i, len;
 349         int temp;
 350         int timeout;
 351
 352         /* clear all the bits (clear-on-write) */
 353         outb_p(0xFF, SMBHSTSTS);
 354         /* make sure SMBus is idle */
 355         temp = inb_p(SMBHSTSTS);
 356         for (timeout = 0;
 357              (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
 358              timeout++) {
 359                 msleep(1);
 360                 temp = inb_p(SMBHSTSTS);
 361         }
 362         if (timeout >= MAX_TIMEOUT) {
 363                 dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
 364         }
 365
 366         switch (size) {
 367         case I2C_SMBUS_QUICK:
 368                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 369                        SMBHSTADD);
 370                 size = ALI15X3_QUICK;
 371                 break;
 372         case I2C_SMBUS_BYTE:
 373                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 374                        SMBHSTADD);
 375                 if (read_write == I2C_SMBUS_WRITE)
 376                         outb_p(command, SMBHSTCMD);
 377                 size = ALI15X3_BYTE;
 378                 break;
 379         case I2C_SMBUS_BYTE_DATA:
 380                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 381                        SMBHSTADD);
 382                 outb_p(command, SMBHSTCMD);
 383                 if (read_write == I2C_SMBUS_WRITE)
 384                         outb_p(data->byte, SMBHSTDAT0);
 385                 size = ALI15X3_BYTE_DATA;
 386                 break;
 387         case I2C_SMBUS_WORD_DATA:
 388                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 389                        SMBHSTADD);
 390                 outb_p(command, SMBHSTCMD);
 391                 if (read_write == I2C_SMBUS_WRITE) {
 392                         outb_p(data->word & 0xff, SMBHSTDAT0);
 393                         outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
 394                 }
 395                 size = ALI15X3_WORD_DATA;
 396                 break;
 397         case I2C_SMBUS_BLOCK_DATA:
 398                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
 399                        SMBHSTADD);
 400                 outb_p(command, SMBHSTCMD);
 401                 if (read_write == I2C_SMBUS_WRITE) {
 402                         len = data->block[0];
 403                         if (len < 0) {
 404                                 len = 0;
 405                                 data->block[0] = len;
 406                         }
 407                         if (len > 32) {
 408                                 len = 32;
 409                                 data->block[0] = len;
 410                         }
 411                         outb_p(len, SMBHSTDAT0);
 412                         /* Reset SMBBLKDAT */
 413                         outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 414                         for (i = 1; i <= len; i++)
 415                                 outb_p(data->block[i], SMBBLKDAT);
 416                 }
 417                 size = ALI15X3_BLOCK_DATA;
 418                 break;
 419         default:
 420                 dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
 421                 return -EOPNOTSUPP;
 422         }
 423
 424         outb_p(size, SMBHSTCNT);        /* output command */
 425
 426         temp = ali15x3_transaction(adap);
 427         if (temp)
 428                 return temp;
 429
 430         if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
 431                 return 0;
 432
 433
 434         switch (size) {
 435         case ALI15X3_BYTE:      /* Result put in SMBHSTDAT0 */
 436                 data->byte = inb_p(SMBHSTDAT0);
 437                 break;
 438         case ALI15X3_BYTE_DATA:
 439                 data->byte = inb_p(SMBHSTDAT0);
 440                 break;
 441         case ALI15X3_WORD_DATA:
 442                 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
 443                 break;
 444         case ALI15X3_BLOCK_DATA:
 445                 len = inb_p(SMBHSTDAT0);
 446                 if (len > 32)
 447                         len = 32;
 448                 data->block[0] = len;
 449                 /* Reset SMBBLKDAT */
 450                 outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
 451                 for (i = 1; i <= data->block[0]; i++) {
 452                         data->block[i] = inb_p(SMBBLKDAT);
 453                         dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
 454                                 len, i, data->block[i]);
 455                 }
 456                 break;
 457         }
 458         return 0;
 459 }
 460
 461 static u32 ali15x3_func(struct i2c_adapter *adapter)
 462 {
 463         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
 464             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
 465             I2C_FUNC_SMBUS_BLOCK_DATA;
 466 }
 467
 468 static const struct i2c_algorithm smbus_algorithm = {
 469         .smbus_xfer     = ali15x3_access,
 470         .functionality  = ali15x3_func,
 471 };
 472
 473 static struct i2c_adapter ali15x3_adapter = {
 474         .owner          = THIS_MODULE,
 475         .class          = I2C_CLASS_HWMON | I2C_CLASS_SPD,
 476         .algo           = &smbus_algorithm,
 477 };
 478
 479 static DEFINE_PCI_DEVICE_TABLE(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 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 sysfs linkage to our parent device */
 495         ali15x3_adapter.dev.parent = &dev->dev;
 496
 497         snprintf(ali15x3_adapter.name, sizeof(ali15x3_adapter.name),
 498                 "SMBus ALI15X3 adapter at %04x", ali15x3_smba);
 499         return i2c_add_adapter(&ali15x3_adapter);
 500 }
 501
 502 static void 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         = ali15x3_remove,
 513 };
 514
 515 module_pci_driver(ali15x3_driver);
 516
 517 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
 518                 "Philip Edelbrock <phil@netroedge.com>, "
 519                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
 520 MODULE_DESCRIPTION("ALI15X3 SMBus driver");
 521 MODULE_LICENSE("GPL");