1 /* 2 * Copyright (c) 2000 Frodo Looijaard <frodol@dds.nl>, 3 * Philip Edelbrock <phil@netroedge.com>, 4 * Mark D. Studebaker <mdsxyz123@yahoo.com>, 5 * Dan Eaton <dan.eaton@rocketlogix.com> and 6 * Stephen Rousset <stephen.rousset@rocketlogix.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) M1535 South Bridge. 26 27 The M1535 is a South bridge for portable systems. 28 It is very similar to the M15x3 South bridges also produced 29 by Acer Labs Inc. Some of the registers within the part 30 have moved and some have been redefined slightly. Additionally, 31 the sequencing of the SMBus transactions has been modified 32 to be more consistent with the sequencing recommended by 33 the manufacturer and observed through testing. These 34 changes are reflected in this driver and can be identified 35 by comparing this driver to the i2c-ali15x3 driver. 36 For an overview of these chips see http://www.acerlabs.com 37 38 The SMB controller is part of the 7101 device, which is an 39 ACPI-compliant Power Management Unit (PMU). 40 41 The whole 7101 device has to be enabled for the SMB to work. 42 You can't just enable the SMB alone. 43 The SMB and the ACPI have separate I/O spaces. 44 We make sure that the SMB is enabled. We leave the ACPI alone. 45 46 This driver controls the SMB Host only. 47 48 This driver does not use interrupts. 49 */ 50 51 52 /* Note: we assume there can only be one ALI1535, with one SMBus interface */ 53 54 #include <linux/module.h> 55 #include <linux/pci.h> 56 #include <linux/kernel.h> 57 #include <linux/stddef.h> 58 #include <linux/delay.h> 59 #include <linux/ioport.h> 60 #include <linux/i2c.h> 61 #include <linux/acpi.h> 62 #include <linux/io.h> 63 64 65 /* ALI1535 SMBus address offsets */ 66 #define SMBHSTSTS (0 + ali1535_smba) 67 #define SMBHSTTYP (1 + ali1535_smba) 68 #define SMBHSTPORT (2 + ali1535_smba) 69 #define SMBHSTCMD (7 + ali1535_smba) 70 #define SMBHSTADD (3 + ali1535_smba) 71 #define SMBHSTDAT0 (4 + ali1535_smba) 72 #define SMBHSTDAT1 (5 + ali1535_smba) 73 #define SMBBLKDAT (6 + ali1535_smba) 74 75 /* PCI Address Constants */ 76 #define SMBCOM 0x004 77 #define SMBREV 0x008 78 #define SMBCFG 0x0D1 79 #define SMBBA 0x0E2 80 #define SMBHSTCFG 0x0F0 81 #define SMBCLK 0x0F2 82 83 /* Other settings */ 84 #define MAX_TIMEOUT 500 /* times 1/100 sec */ 85 #define ALI1535_SMB_IOSIZE 32 86 87 #define ALI1535_SMB_DEFAULTBASE 0x8040 88 89 /* ALI1535 address lock bits */ 90 #define ALI1535_LOCK 0x06 /* dwe */ 91 92 /* ALI1535 command constants */ 93 #define ALI1535_QUICK 0x00 94 #define ALI1535_BYTE 0x10 95 #define ALI1535_BYTE_DATA 0x20 96 #define ALI1535_WORD_DATA 0x30 97 #define ALI1535_BLOCK_DATA 0x40 98 #define ALI1535_I2C_READ 0x60 99 100 #define ALI1535_DEV10B_EN 0x80 /* Enable 10-bit addressing in */ 101 /* I2C read */ 102 #define ALI1535_T_OUT 0x08 /* Time-out Command (write) */ 103 #define ALI1535_A_HIGH_BIT9 0x08 /* Bit 9 of 10-bit address in */ 104 /* Alert-Response-Address */ 105 /* (read) */ 106 #define ALI1535_KILL 0x04 /* Kill Command (write) */ 107 #define ALI1535_A_HIGH_BIT8 0x04 /* Bit 8 of 10-bit address in */ 108 /* Alert-Response-Address */ 109 /* (read) */ 110 111 #define ALI1535_D_HI_MASK 0x03 /* Mask for isolating bits 9-8 */ 112 /* of 10-bit address in I2C */ 113 /* Read Command */ 114 115 /* ALI1535 status register bits */ 116 #define ALI1535_STS_IDLE 0x04 117 #define ALI1535_STS_BUSY 0x08 /* host busy */ 118 #define ALI1535_STS_DONE 0x10 /* transaction complete */ 119 #define ALI1535_STS_DEV 0x20 /* device error */ 120 #define ALI1535_STS_BUSERR 0x40 /* bus error */ 121 #define ALI1535_STS_FAIL 0x80 /* failed bus transaction */ 122 #define ALI1535_STS_ERR 0xE0 /* all the bad error bits */ 123 124 #define ALI1535_BLOCK_CLR 0x04 /* reset block data index */ 125 126 /* ALI1535 device address register bits */ 127 #define ALI1535_RD_ADDR 0x01 /* Read/Write Bit in Device */ 128 /* Address field */ 129 /* -> Write = 0 */ 130 /* -> Read = 1 */ 131 #define ALI1535_SMBIO_EN 0x04 /* SMB I/O Space enable */ 132 133 static struct pci_driver ali1535_driver; 134 static unsigned long ali1535_smba; 135 static unsigned short ali1535_offset; 136 137 /* Detect whether a ALI1535 can be found, and initialize it, where necessary. 138 Note the differences between kernels with the old PCI BIOS interface and 139 newer kernels with the real PCI interface. In compat.h some things are 140 defined to make the transition easier. */ 141 static int ali1535_setup(struct pci_dev *dev) 142 { 143 int retval; 144 unsigned char temp; 145 146 /* Check the following things: 147 - SMB I/O address is initialized 148 - Device is enabled 149 - We can use the addresses 150 */ 151 152 retval = pci_enable_device(dev); 153 if (retval) { 154 dev_err(&dev->dev, "ALI1535_smb can't enable device\n"); 155 goto exit; 156 } 157 158 /* Determine the address of the SMBus area */ 159 pci_read_config_word(dev, SMBBA, &ali1535_offset); 160 dev_dbg(&dev->dev, "ALI1535_smb is at offset 0x%04x\n", ali1535_offset); 161 ali1535_offset &= (0xffff & ~(ALI1535_SMB_IOSIZE - 1)); 162 if (ali1535_offset == 0) { 163 dev_warn(&dev->dev, 164 "ALI1535_smb region uninitialized - upgrade BIOS?\n"); 165 retval = -ENODEV; 166 goto exit; 167 } 168 169 if (pci_resource_flags(dev, 0) & IORESOURCE_IO) 170 ali1535_smba = pci_resource_start(dev, 0) + ali1535_offset; 171 else 172 ali1535_smba = ali1535_offset; 173 174 retval = acpi_check_region(ali1535_smba, ALI1535_SMB_IOSIZE, 175 ali1535_driver.name); 176 if (retval) 177 goto exit; 178 179 if (!request_region(ali1535_smba, ALI1535_SMB_IOSIZE, 180 ali1535_driver.name)) { 181 dev_err(&dev->dev, "ALI1535_smb region 0x%lx already in use!\n", 182 ali1535_smba); 183 retval = -EBUSY; 184 goto exit; 185 } 186 187 /* check if whole device is enabled */ 188 pci_read_config_byte(dev, SMBCFG, &temp); 189 if ((temp & ALI1535_SMBIO_EN) == 0) { 190 dev_err(&dev->dev, "SMB device not enabled - upgrade BIOS?\n"); 191 retval = -ENODEV; 192 goto exit_free; 193 } 194 195 /* Is SMB Host controller enabled? */ 196 pci_read_config_byte(dev, SMBHSTCFG, &temp); 197 if ((temp & 1) == 0) { 198 dev_err(&dev->dev, "SMBus controller not enabled - upgrade BIOS?\n"); 199 retval = -ENODEV; 200 goto exit_free; 201 } 202 203 /* set SMB clock to 74KHz as recommended in data sheet */ 204 pci_write_config_byte(dev, SMBCLK, 0x20); 205 206 /* 207 The interrupt routing for SMB is set up in register 0x77 in the 208 1533 ISA Bridge device, NOT in the 7101 device. 209 Don't bother with finding the 1533 device and reading the register. 210 if ((....... & 0x0F) == 1) 211 dev_dbg(&dev->dev, "ALI1535 using Interrupt 9 for SMBus.\n"); 212 */ 213 pci_read_config_byte(dev, SMBREV, &temp); 214 dev_dbg(&dev->dev, "SMBREV = 0x%X\n", temp); 215 dev_dbg(&dev->dev, "ALI1535_smba = 0x%lx\n", ali1535_smba); 216 217 return 0; 218 219 exit_free: 220 release_region(ali1535_smba, ALI1535_SMB_IOSIZE); 221 exit: 222 return retval; 223 } 224 225 static int ali1535_transaction(struct i2c_adapter *adap) 226 { 227 int temp; 228 int result = 0; 229 int timeout = 0; 230 231 dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, TYP=%02x, " 232 "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", 233 inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), 234 inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); 235 236 /* get status */ 237 temp = inb_p(SMBHSTSTS); 238 239 /* Make sure the SMBus host is ready to start transmitting */ 240 /* Check the busy bit first */ 241 if (temp & ALI1535_STS_BUSY) { 242 /* If the host controller is still busy, it may have timed out 243 * in the previous transaction, resulting in a "SMBus Timeout" 244 * printk. I've tried the following to reset a stuck busy bit. 245 * 1. Reset the controller with an KILL command. (this 246 * doesn't seem to clear the controller if an external 247 * device is hung) 248 * 2. Reset the controller and the other SMBus devices with a 249 * T_OUT command. (this clears the host busy bit if an 250 * external device is hung, but it comes back upon a new 251 * access to a device) 252 * 3. Disable and reenable the controller in SMBHSTCFG. Worst 253 * case, nothing seems to work except power reset. 254 */ 255 256 /* Try resetting entire SMB bus, including other devices - This 257 * may not work either - it clears the BUSY bit but then the 258 * BUSY bit may come back on when you try and use the chip 259 * again. If that's the case you are stuck. 260 */ 261 dev_info(&adap->dev, 262 "Resetting entire SMB Bus to clear busy condition (%02x)\n", 263 temp); 264 outb_p(ALI1535_T_OUT, SMBHSTTYP); 265 temp = inb_p(SMBHSTSTS); 266 } 267 268 /* now check the error bits and the busy bit */ 269 if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { 270 /* do a clear-on-write */ 271 outb_p(0xFF, SMBHSTSTS); 272 temp = inb_p(SMBHSTSTS); 273 if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { 274 /* This is probably going to be correctable only by a 275 * power reset as one of the bits now appears to be 276 * stuck */ 277 /* This may be a bus or device with electrical problems. */ 278 dev_err(&adap->dev, 279 "SMBus reset failed! (0x%02x) - controller or " 280 "device on bus is probably hung\n", temp); 281 return -EBUSY; 282 } 283 } else { 284 /* check and clear done bit */ 285 if (temp & ALI1535_STS_DONE) 286 outb_p(temp, SMBHSTSTS); 287 } 288 289 /* start the transaction by writing anything to the start register */ 290 outb_p(0xFF, SMBHSTPORT); 291 292 /* We will always wait for a fraction of a second! */ 293 timeout = 0; 294 do { 295 usleep_range(1000, 2000); 296 temp = inb_p(SMBHSTSTS); 297 } while (((temp & ALI1535_STS_BUSY) && !(temp & ALI1535_STS_IDLE)) 298 && (timeout++ < MAX_TIMEOUT)); 299 300 /* If the SMBus is still busy, we give up */ 301 if (timeout > MAX_TIMEOUT) { 302 result = -ETIMEDOUT; 303 dev_err(&adap->dev, "SMBus Timeout!\n"); 304 } 305 306 if (temp & ALI1535_STS_FAIL) { 307 result = -EIO; 308 dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); 309 } 310 311 /* Unfortunately the ALI SMB controller maps "no response" and "bus 312 * collision" into a single bit. No response is the usual case so don't 313 * do a printk. This means that bus collisions go unreported. 314 */ 315 if (temp & ALI1535_STS_BUSERR) { 316 result = -ENXIO; 317 dev_dbg(&adap->dev, 318 "Error: no response or bus collision ADD=%02x\n", 319 inb_p(SMBHSTADD)); 320 } 321 322 /* haven't ever seen this */ 323 if (temp & ALI1535_STS_DEV) { 324 result = -EIO; 325 dev_err(&adap->dev, "Error: device error\n"); 326 } 327 328 /* check to see if the "command complete" indication is set */ 329 if (!(temp & ALI1535_STS_DONE)) { 330 result = -ETIMEDOUT; 331 dev_err(&adap->dev, "Error: command never completed\n"); 332 } 333 334 dev_dbg(&adap->dev, "Transaction (post): STS=%02x, TYP=%02x, " 335 "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", 336 inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), 337 inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); 338 339 /* take consequent actions for error conditions */ 340 if (!(temp & ALI1535_STS_DONE)) { 341 /* issue "kill" to reset host controller */ 342 outb_p(ALI1535_KILL, SMBHSTTYP); 343 outb_p(0xFF, SMBHSTSTS); 344 } else if (temp & ALI1535_STS_ERR) { 345 /* issue "timeout" to reset all devices on bus */ 346 outb_p(ALI1535_T_OUT, SMBHSTTYP); 347 outb_p(0xFF, SMBHSTSTS); 348 } 349 350 return result; 351 } 352 353 /* Return negative errno on error. */ 354 static s32 ali1535_access(struct i2c_adapter *adap, u16 addr, 355 unsigned short flags, char read_write, u8 command, 356 int size, union i2c_smbus_data *data) 357 { 358 int i, len; 359 int temp; 360 int timeout; 361 s32 result = 0; 362 363 /* make sure SMBus is idle */ 364 temp = inb_p(SMBHSTSTS); 365 for (timeout = 0; 366 (timeout < MAX_TIMEOUT) && !(temp & ALI1535_STS_IDLE); 367 timeout++) { 368 usleep_range(1000, 2000); 369 temp = inb_p(SMBHSTSTS); 370 } 371 if (timeout >= MAX_TIMEOUT) 372 dev_warn(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp); 373 374 /* clear status register (clear-on-write) */ 375 outb_p(0xFF, SMBHSTSTS); 376 377 switch (size) { 378 case I2C_SMBUS_QUICK: 379 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 380 SMBHSTADD); 381 size = ALI1535_QUICK; 382 outb_p(size, SMBHSTTYP); /* output command */ 383 break; 384 case I2C_SMBUS_BYTE: 385 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 386 SMBHSTADD); 387 size = ALI1535_BYTE; 388 outb_p(size, SMBHSTTYP); /* output command */ 389 if (read_write == I2C_SMBUS_WRITE) 390 outb_p(command, SMBHSTCMD); 391 break; 392 case I2C_SMBUS_BYTE_DATA: 393 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 394 SMBHSTADD); 395 size = ALI1535_BYTE_DATA; 396 outb_p(size, SMBHSTTYP); /* output command */ 397 outb_p(command, SMBHSTCMD); 398 if (read_write == I2C_SMBUS_WRITE) 399 outb_p(data->byte, SMBHSTDAT0); 400 break; 401 case I2C_SMBUS_WORD_DATA: 402 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 403 SMBHSTADD); 404 size = ALI1535_WORD_DATA; 405 outb_p(size, SMBHSTTYP); /* output command */ 406 outb_p(command, SMBHSTCMD); 407 if (read_write == I2C_SMBUS_WRITE) { 408 outb_p(data->word & 0xff, SMBHSTDAT0); 409 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); 410 } 411 break; 412 case I2C_SMBUS_BLOCK_DATA: 413 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 414 SMBHSTADD); 415 size = ALI1535_BLOCK_DATA; 416 outb_p(size, SMBHSTTYP); /* output command */ 417 outb_p(command, SMBHSTCMD); 418 if (read_write == I2C_SMBUS_WRITE) { 419 len = data->block[0]; 420 if (len < 0) { 421 len = 0; 422 data->block[0] = len; 423 } 424 if (len > 32) { 425 len = 32; 426 data->block[0] = len; 427 } 428 outb_p(len, SMBHSTDAT0); 429 /* Reset SMBBLKDAT */ 430 outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); 431 for (i = 1; i <= len; i++) 432 outb_p(data->block[i], SMBBLKDAT); 433 } 434 break; 435 default: 436 dev_warn(&adap->dev, "Unsupported transaction %d\n", size); 437 result = -EOPNOTSUPP; 438 goto EXIT; 439 } 440 441 result = ali1535_transaction(adap); 442 if (result) 443 goto EXIT; 444 445 if ((read_write == I2C_SMBUS_WRITE) || (size == ALI1535_QUICK)) { 446 result = 0; 447 goto EXIT; 448 } 449 450 switch (size) { 451 case ALI1535_BYTE: /* Result put in SMBHSTDAT0 */ 452 data->byte = inb_p(SMBHSTDAT0); 453 break; 454 case ALI1535_BYTE_DATA: 455 data->byte = inb_p(SMBHSTDAT0); 456 break; 457 case ALI1535_WORD_DATA: 458 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); 459 break; 460 case ALI1535_BLOCK_DATA: 461 len = inb_p(SMBHSTDAT0); 462 if (len > 32) 463 len = 32; 464 data->block[0] = len; 465 /* Reset SMBBLKDAT */ 466 outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); 467 for (i = 1; i <= data->block[0]; i++) { 468 data->block[i] = inb_p(SMBBLKDAT); 469 dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n", 470 len, i, data->block[i]); 471 } 472 break; 473 } 474 EXIT: 475 return result; 476 } 477 478 479 static u32 ali1535_func(struct i2c_adapter *adapter) 480 { 481 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 482 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 483 I2C_FUNC_SMBUS_BLOCK_DATA; 484 } 485 486 static const struct i2c_algorithm smbus_algorithm = { 487 .smbus_xfer = ali1535_access, 488 .functionality = ali1535_func, 489 }; 490 491 static struct i2c_adapter ali1535_adapter = { 492 .owner = THIS_MODULE, 493 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, 494 .algo = &smbus_algorithm, 495 }; 496 497 static const struct pci_device_id ali1535_ids[] = { 498 { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) }, 499 { }, 500 }; 501 502 MODULE_DEVICE_TABLE(pci, ali1535_ids); 503 504 static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id) 505 { 506 if (ali1535_setup(dev)) { 507 dev_warn(&dev->dev, 508 "ALI1535 not detected, module not inserted.\n"); 509 return -ENODEV; 510 } 511 512 /* set up the sysfs linkage to our parent device */ 513 ali1535_adapter.dev.parent = &dev->dev; 514 515 snprintf(ali1535_adapter.name, sizeof(ali1535_adapter.name), 516 "SMBus ALI1535 adapter at %04x", ali1535_offset); 517 return i2c_add_adapter(&ali1535_adapter); 518 } 519 520 static void ali1535_remove(struct pci_dev *dev) 521 { 522 i2c_del_adapter(&ali1535_adapter); 523 release_region(ali1535_smba, ALI1535_SMB_IOSIZE); 524 } 525 526 static struct pci_driver ali1535_driver = { 527 .name = "ali1535_smbus", 528 .id_table = ali1535_ids, 529 .probe = ali1535_probe, 530 .remove = ali1535_remove, 531 }; 532 533 module_pci_driver(ali1535_driver); 534 535 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, " 536 "Philip Edelbrock <phil@netroedge.com>, " 537 "Mark D. Studebaker <mdsxyz123@yahoo.com> " 538 "and Dan Eaton <dan.eaton@rocketlogix.com>"); 539 MODULE_DESCRIPTION("ALI1535 SMBus driver"); 540 MODULE_LICENSE("GPL"); 541