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/init.h> 62 #include <linux/acpi.h> 63 #include <linux/io.h> 64 65 66 /* ALI1535 SMBus address offsets */ 67 #define SMBHSTSTS (0 + ali1535_smba) 68 #define SMBHSTTYP (1 + ali1535_smba) 69 #define SMBHSTPORT (2 + ali1535_smba) 70 #define SMBHSTCMD (7 + ali1535_smba) 71 #define SMBHSTADD (3 + ali1535_smba) 72 #define SMBHSTDAT0 (4 + ali1535_smba) 73 #define SMBHSTDAT1 (5 + ali1535_smba) 74 #define SMBBLKDAT (6 + ali1535_smba) 75 76 /* PCI Address Constants */ 77 #define SMBCOM 0x004 78 #define SMBREV 0x008 79 #define SMBCFG 0x0D1 80 #define SMBBA 0x0E2 81 #define SMBHSTCFG 0x0F0 82 #define SMBCLK 0x0F2 83 84 /* Other settings */ 85 #define MAX_TIMEOUT 500 /* times 1/100 sec */ 86 #define ALI1535_SMB_IOSIZE 32 87 88 #define ALI1535_SMB_DEFAULTBASE 0x8040 89 90 /* ALI1535 address lock bits */ 91 #define ALI1535_LOCK 0x06 /* dwe */ 92 93 /* ALI1535 command constants */ 94 #define ALI1535_QUICK 0x00 95 #define ALI1535_BYTE 0x10 96 #define ALI1535_BYTE_DATA 0x20 97 #define ALI1535_WORD_DATA 0x30 98 #define ALI1535_BLOCK_DATA 0x40 99 #define ALI1535_I2C_READ 0x60 100 101 #define ALI1535_DEV10B_EN 0x80 /* Enable 10-bit addressing in */ 102 /* I2C read */ 103 #define ALI1535_T_OUT 0x08 /* Time-out Command (write) */ 104 #define ALI1535_A_HIGH_BIT9 0x08 /* Bit 9 of 10-bit address in */ 105 /* Alert-Response-Address */ 106 /* (read) */ 107 #define ALI1535_KILL 0x04 /* Kill Command (write) */ 108 #define ALI1535_A_HIGH_BIT8 0x04 /* Bit 8 of 10-bit address in */ 109 /* Alert-Response-Address */ 110 /* (read) */ 111 112 #define ALI1535_D_HI_MASK 0x03 /* Mask for isolating bits 9-8 */ 113 /* of 10-bit address in I2C */ 114 /* Read Command */ 115 116 /* ALI1535 status register bits */ 117 #define ALI1535_STS_IDLE 0x04 118 #define ALI1535_STS_BUSY 0x08 /* host busy */ 119 #define ALI1535_STS_DONE 0x10 /* transaction complete */ 120 #define ALI1535_STS_DEV 0x20 /* device error */ 121 #define ALI1535_STS_BUSERR 0x40 /* bus error */ 122 #define ALI1535_STS_FAIL 0x80 /* failed bus transaction */ 123 #define ALI1535_STS_ERR 0xE0 /* all the bad error bits */ 124 125 #define ALI1535_BLOCK_CLR 0x04 /* reset block data index */ 126 127 /* ALI1535 device address register bits */ 128 #define ALI1535_RD_ADDR 0x01 /* Read/Write Bit in Device */ 129 /* Address field */ 130 /* -> Write = 0 */ 131 /* -> Read = 1 */ 132 #define ALI1535_SMBIO_EN 0x04 /* SMB I/O Space enable */ 133 134 static struct pci_driver ali1535_driver; 135 static unsigned long ali1535_smba; 136 static unsigned short ali1535_offset; 137 138 /* Detect whether a ALI1535 can be found, and initialize it, where necessary. 139 Note the differences between kernels with the old PCI BIOS interface and 140 newer kernels with the real PCI interface. In compat.h some things are 141 defined to make the transition easier. */ 142 static int ali1535_setup(struct pci_dev *dev) 143 { 144 int retval; 145 unsigned char temp; 146 147 /* Check the following things: 148 - SMB I/O address is initialized 149 - Device is enabled 150 - We can use the addresses 151 */ 152 153 retval = pci_enable_device(dev); 154 if (retval) { 155 dev_err(&dev->dev, "ALI1535_smb can't enable device\n"); 156 goto exit; 157 } 158 159 /* Determine the address of the SMBus area */ 160 pci_read_config_word(dev, SMBBA, &ali1535_offset); 161 dev_dbg(&dev->dev, "ALI1535_smb is at offset 0x%04x\n", ali1535_offset); 162 ali1535_offset &= (0xffff & ~(ALI1535_SMB_IOSIZE - 1)); 163 if (ali1535_offset == 0) { 164 dev_warn(&dev->dev, 165 "ALI1535_smb region uninitialized - upgrade BIOS?\n"); 166 retval = -ENODEV; 167 goto exit; 168 } 169 170 if (pci_resource_flags(dev, 0) & IORESOURCE_IO) 171 ali1535_smba = pci_resource_start(dev, 0) + ali1535_offset; 172 else 173 ali1535_smba = ali1535_offset; 174 175 retval = acpi_check_region(ali1535_smba, ALI1535_SMB_IOSIZE, 176 ali1535_driver.name); 177 if (retval) 178 goto exit; 179 180 if (!request_region(ali1535_smba, ALI1535_SMB_IOSIZE, 181 ali1535_driver.name)) { 182 dev_err(&dev->dev, "ALI1535_smb region 0x%lx already in use!\n", 183 ali1535_smba); 184 retval = -EBUSY; 185 goto exit; 186 } 187 188 /* check if whole device is enabled */ 189 pci_read_config_byte(dev, SMBCFG, &temp); 190 if ((temp & ALI1535_SMBIO_EN) == 0) { 191 dev_err(&dev->dev, "SMB device not enabled - upgrade BIOS?\n"); 192 retval = -ENODEV; 193 goto exit_free; 194 } 195 196 /* Is SMB Host controller enabled? */ 197 pci_read_config_byte(dev, SMBHSTCFG, &temp); 198 if ((temp & 1) == 0) { 199 dev_err(&dev->dev, "SMBus controller not enabled - upgrade BIOS?\n"); 200 retval = -ENODEV; 201 goto exit_free; 202 } 203 204 /* set SMB clock to 74KHz as recommended in data sheet */ 205 pci_write_config_byte(dev, SMBCLK, 0x20); 206 207 /* 208 The interrupt routing for SMB is set up in register 0x77 in the 209 1533 ISA Bridge device, NOT in the 7101 device. 210 Don't bother with finding the 1533 device and reading the register. 211 if ((....... & 0x0F) == 1) 212 dev_dbg(&dev->dev, "ALI1535 using Interrupt 9 for SMBus.\n"); 213 */ 214 pci_read_config_byte(dev, SMBREV, &temp); 215 dev_dbg(&dev->dev, "SMBREV = 0x%X\n", temp); 216 dev_dbg(&dev->dev, "ALI1535_smba = 0x%lx\n", ali1535_smba); 217 218 return 0; 219 220 exit_free: 221 release_region(ali1535_smba, ALI1535_SMB_IOSIZE); 222 exit: 223 return retval; 224 } 225 226 static int ali1535_transaction(struct i2c_adapter *adap) 227 { 228 int temp; 229 int result = 0; 230 int timeout = 0; 231 232 dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, TYP=%02x, " 233 "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", 234 inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), 235 inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); 236 237 /* get status */ 238 temp = inb_p(SMBHSTSTS); 239 240 /* Make sure the SMBus host is ready to start transmitting */ 241 /* Check the busy bit first */ 242 if (temp & ALI1535_STS_BUSY) { 243 /* If the host controller is still busy, it may have timed out 244 * in the previous transaction, resulting in a "SMBus Timeout" 245 * printk. I've tried the following to reset a stuck busy bit. 246 * 1. Reset the controller with an KILL command. (this 247 * doesn't seem to clear the controller if an external 248 * device is hung) 249 * 2. Reset the controller and the other SMBus devices with a 250 * T_OUT command. (this clears the host busy bit if an 251 * external device is hung, but it comes back upon a new 252 * access to a device) 253 * 3. Disable and reenable the controller in SMBHSTCFG. Worst 254 * case, nothing seems to work except power reset. 255 */ 256 257 /* Try resetting entire SMB bus, including other devices - This 258 * may not work either - it clears the BUSY bit but then the 259 * BUSY bit may come back on when you try and use the chip 260 * again. If that's the case you are stuck. 261 */ 262 dev_info(&adap->dev, 263 "Resetting entire SMB Bus to clear busy condition (%02x)\n", 264 temp); 265 outb_p(ALI1535_T_OUT, SMBHSTTYP); 266 temp = inb_p(SMBHSTSTS); 267 } 268 269 /* now check the error bits and the busy bit */ 270 if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { 271 /* do a clear-on-write */ 272 outb_p(0xFF, SMBHSTSTS); 273 temp = inb_p(SMBHSTSTS); 274 if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { 275 /* This is probably going to be correctable only by a 276 * power reset as one of the bits now appears to be 277 * stuck */ 278 /* This may be a bus or device with electrical problems. */ 279 dev_err(&adap->dev, 280 "SMBus reset failed! (0x%02x) - controller or " 281 "device on bus is probably hung\n", temp); 282 return -EBUSY; 283 } 284 } else { 285 /* check and clear done bit */ 286 if (temp & ALI1535_STS_DONE) 287 outb_p(temp, SMBHSTSTS); 288 } 289 290 /* start the transaction by writing anything to the start register */ 291 outb_p(0xFF, SMBHSTPORT); 292 293 /* We will always wait for a fraction of a second! */ 294 timeout = 0; 295 do { 296 usleep_range(1000, 2000); 297 temp = inb_p(SMBHSTSTS); 298 } while (((temp & ALI1535_STS_BUSY) && !(temp & ALI1535_STS_IDLE)) 299 && (timeout++ < MAX_TIMEOUT)); 300 301 /* If the SMBus is still busy, we give up */ 302 if (timeout > MAX_TIMEOUT) { 303 result = -ETIMEDOUT; 304 dev_err(&adap->dev, "SMBus Timeout!\n"); 305 } 306 307 if (temp & ALI1535_STS_FAIL) { 308 result = -EIO; 309 dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); 310 } 311 312 /* Unfortunately the ALI SMB controller maps "no response" and "bus 313 * collision" into a single bit. No response is the usual case so don't 314 * do a printk. This means that bus collisions go unreported. 315 */ 316 if (temp & ALI1535_STS_BUSERR) { 317 result = -ENXIO; 318 dev_dbg(&adap->dev, 319 "Error: no response or bus collision ADD=%02x\n", 320 inb_p(SMBHSTADD)); 321 } 322 323 /* haven't ever seen this */ 324 if (temp & ALI1535_STS_DEV) { 325 result = -EIO; 326 dev_err(&adap->dev, "Error: device error\n"); 327 } 328 329 /* check to see if the "command complete" indication is set */ 330 if (!(temp & ALI1535_STS_DONE)) { 331 result = -ETIMEDOUT; 332 dev_err(&adap->dev, "Error: command never completed\n"); 333 } 334 335 dev_dbg(&adap->dev, "Transaction (post): STS=%02x, TYP=%02x, " 336 "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", 337 inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), 338 inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); 339 340 /* take consequent actions for error conditions */ 341 if (!(temp & ALI1535_STS_DONE)) { 342 /* issue "kill" to reset host controller */ 343 outb_p(ALI1535_KILL, SMBHSTTYP); 344 outb_p(0xFF, SMBHSTSTS); 345 } else if (temp & ALI1535_STS_ERR) { 346 /* issue "timeout" to reset all devices on bus */ 347 outb_p(ALI1535_T_OUT, SMBHSTTYP); 348 outb_p(0xFF, SMBHSTSTS); 349 } 350 351 return result; 352 } 353 354 /* Return negative errno on error. */ 355 static s32 ali1535_access(struct i2c_adapter *adap, u16 addr, 356 unsigned short flags, char read_write, u8 command, 357 int size, union i2c_smbus_data *data) 358 { 359 int i, len; 360 int temp; 361 int timeout; 362 s32 result = 0; 363 364 /* make sure SMBus is idle */ 365 temp = inb_p(SMBHSTSTS); 366 for (timeout = 0; 367 (timeout < MAX_TIMEOUT) && !(temp & ALI1535_STS_IDLE); 368 timeout++) { 369 usleep_range(1000, 2000); 370 temp = inb_p(SMBHSTSTS); 371 } 372 if (timeout >= MAX_TIMEOUT) 373 dev_warn(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp); 374 375 /* clear status register (clear-on-write) */ 376 outb_p(0xFF, SMBHSTSTS); 377 378 switch (size) { 379 case I2C_SMBUS_QUICK: 380 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 381 SMBHSTADD); 382 size = ALI1535_QUICK; 383 outb_p(size, SMBHSTTYP); /* output command */ 384 break; 385 case I2C_SMBUS_BYTE: 386 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 387 SMBHSTADD); 388 size = ALI1535_BYTE; 389 outb_p(size, SMBHSTTYP); /* output command */ 390 if (read_write == I2C_SMBUS_WRITE) 391 outb_p(command, SMBHSTCMD); 392 break; 393 case I2C_SMBUS_BYTE_DATA: 394 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 395 SMBHSTADD); 396 size = ALI1535_BYTE_DATA; 397 outb_p(size, SMBHSTTYP); /* output command */ 398 outb_p(command, SMBHSTCMD); 399 if (read_write == I2C_SMBUS_WRITE) 400 outb_p(data->byte, SMBHSTDAT0); 401 break; 402 case I2C_SMBUS_WORD_DATA: 403 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 404 SMBHSTADD); 405 size = ALI1535_WORD_DATA; 406 outb_p(size, SMBHSTTYP); /* output command */ 407 outb_p(command, SMBHSTCMD); 408 if (read_write == I2C_SMBUS_WRITE) { 409 outb_p(data->word & 0xff, SMBHSTDAT0); 410 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); 411 } 412 break; 413 case I2C_SMBUS_BLOCK_DATA: 414 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 415 SMBHSTADD); 416 size = ALI1535_BLOCK_DATA; 417 outb_p(size, SMBHSTTYP); /* output command */ 418 outb_p(command, SMBHSTCMD); 419 if (read_write == I2C_SMBUS_WRITE) { 420 len = data->block[0]; 421 if (len < 0) { 422 len = 0; 423 data->block[0] = len; 424 } 425 if (len > 32) { 426 len = 32; 427 data->block[0] = len; 428 } 429 outb_p(len, SMBHSTDAT0); 430 /* Reset SMBBLKDAT */ 431 outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); 432 for (i = 1; i <= len; i++) 433 outb_p(data->block[i], SMBBLKDAT); 434 } 435 break; 436 default: 437 dev_warn(&adap->dev, "Unsupported transaction %d\n", size); 438 result = -EOPNOTSUPP; 439 goto EXIT; 440 } 441 442 result = ali1535_transaction(adap); 443 if (result) 444 goto EXIT; 445 446 if ((read_write == I2C_SMBUS_WRITE) || (size == ALI1535_QUICK)) { 447 result = 0; 448 goto EXIT; 449 } 450 451 switch (size) { 452 case ALI1535_BYTE: /* Result put in SMBHSTDAT0 */ 453 data->byte = inb_p(SMBHSTDAT0); 454 break; 455 case ALI1535_BYTE_DATA: 456 data->byte = inb_p(SMBHSTDAT0); 457 break; 458 case ALI1535_WORD_DATA: 459 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); 460 break; 461 case ALI1535_BLOCK_DATA: 462 len = inb_p(SMBHSTDAT0); 463 if (len > 32) 464 len = 32; 465 data->block[0] = len; 466 /* Reset SMBBLKDAT */ 467 outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); 468 for (i = 1; i <= data->block[0]; i++) { 469 data->block[i] = inb_p(SMBBLKDAT); 470 dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n", 471 len, i, data->block[i]); 472 } 473 break; 474 } 475 EXIT: 476 return result; 477 } 478 479 480 static u32 ali1535_func(struct i2c_adapter *adapter) 481 { 482 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 483 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 484 I2C_FUNC_SMBUS_BLOCK_DATA; 485 } 486 487 static const struct i2c_algorithm smbus_algorithm = { 488 .smbus_xfer = ali1535_access, 489 .functionality = ali1535_func, 490 }; 491 492 static struct i2c_adapter ali1535_adapter = { 493 .owner = THIS_MODULE, 494 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, 495 .algo = &smbus_algorithm, 496 }; 497 498 static DEFINE_PCI_DEVICE_TABLE(ali1535_ids) = { 499 { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) }, 500 { }, 501 }; 502 503 MODULE_DEVICE_TABLE(pci, ali1535_ids); 504 505 static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id) 506 { 507 if (ali1535_setup(dev)) { 508 dev_warn(&dev->dev, 509 "ALI1535 not detected, module not inserted.\n"); 510 return -ENODEV; 511 } 512 513 /* set up the sysfs linkage to our parent device */ 514 ali1535_adapter.dev.parent = &dev->dev; 515 516 snprintf(ali1535_adapter.name, sizeof(ali1535_adapter.name), 517 "SMBus ALI1535 adapter at %04x", ali1535_offset); 518 return i2c_add_adapter(&ali1535_adapter); 519 } 520 521 static void ali1535_remove(struct pci_dev *dev) 522 { 523 i2c_del_adapter(&ali1535_adapter); 524 release_region(ali1535_smba, ALI1535_SMB_IOSIZE); 525 } 526 527 static struct pci_driver ali1535_driver = { 528 .name = "ali1535_smbus", 529 .id_table = ali1535_ids, 530 .probe = ali1535_probe, 531 .remove = ali1535_remove, 532 }; 533 534 module_pci_driver(ali1535_driver); 535 536 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, " 537 "Philip Edelbrock <phil@netroedge.com>, " 538 "Mark D. Studebaker <mdsxyz123@yahoo.com> " 539 "and Dan Eaton <dan.eaton@rocketlogix.com>"); 540 MODULE_DESCRIPTION("ALI1535 SMBus driver"); 541 MODULE_LICENSE("GPL"); 542