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 19 /* 20 This is the driver for the SMB Host controller on 21 Acer Labs Inc. (ALI) M1535 South Bridge. 22 23 The M1535 is a South bridge for portable systems. 24 It is very similar to the M15x3 South bridges also produced 25 by Acer Labs Inc. Some of the registers within the part 26 have moved and some have been redefined slightly. Additionally, 27 the sequencing of the SMBus transactions has been modified 28 to be more consistent with the sequencing recommended by 29 the manufacturer and observed through testing. These 30 changes are reflected in this driver and can be identified 31 by comparing this driver to the i2c-ali15x3 driver. 32 For an overview of these chips see http://www.acerlabs.com 33 34 The SMB controller is part of the 7101 device, which is an 35 ACPI-compliant Power Management Unit (PMU). 36 37 The whole 7101 device has to be enabled for the SMB to work. 38 You can't just enable the SMB alone. 39 The SMB and the ACPI have separate I/O spaces. 40 We make sure that the SMB is enabled. We leave the ACPI alone. 41 42 This driver controls the SMB Host only. 43 44 This driver does not use interrupts. 45 */ 46 47 48 /* Note: we assume there can only be one ALI1535, with one SMBus interface */ 49 50 #include <linux/module.h> 51 #include <linux/pci.h> 52 #include <linux/kernel.h> 53 #include <linux/stddef.h> 54 #include <linux/delay.h> 55 #include <linux/ioport.h> 56 #include <linux/i2c.h> 57 #include <linux/acpi.h> 58 #include <linux/io.h> 59 60 61 /* ALI1535 SMBus address offsets */ 62 #define SMBHSTSTS (0 + ali1535_smba) 63 #define SMBHSTTYP (1 + ali1535_smba) 64 #define SMBHSTPORT (2 + ali1535_smba) 65 #define SMBHSTCMD (7 + ali1535_smba) 66 #define SMBHSTADD (3 + ali1535_smba) 67 #define SMBHSTDAT0 (4 + ali1535_smba) 68 #define SMBHSTDAT1 (5 + ali1535_smba) 69 #define SMBBLKDAT (6 + ali1535_smba) 70 71 /* PCI Address Constants */ 72 #define SMBCOM 0x004 73 #define SMBREV 0x008 74 #define SMBCFG 0x0D1 75 #define SMBBA 0x0E2 76 #define SMBHSTCFG 0x0F0 77 #define SMBCLK 0x0F2 78 79 /* Other settings */ 80 #define MAX_TIMEOUT 500 /* times 1/100 sec */ 81 #define ALI1535_SMB_IOSIZE 32 82 83 #define ALI1535_SMB_DEFAULTBASE 0x8040 84 85 /* ALI1535 address lock bits */ 86 #define ALI1535_LOCK 0x06 /* dwe */ 87 88 /* ALI1535 command constants */ 89 #define ALI1535_QUICK 0x00 90 #define ALI1535_BYTE 0x10 91 #define ALI1535_BYTE_DATA 0x20 92 #define ALI1535_WORD_DATA 0x30 93 #define ALI1535_BLOCK_DATA 0x40 94 #define ALI1535_I2C_READ 0x60 95 96 #define ALI1535_DEV10B_EN 0x80 /* Enable 10-bit addressing in */ 97 /* I2C read */ 98 #define ALI1535_T_OUT 0x08 /* Time-out Command (write) */ 99 #define ALI1535_A_HIGH_BIT9 0x08 /* Bit 9 of 10-bit address in */ 100 /* Alert-Response-Address */ 101 /* (read) */ 102 #define ALI1535_KILL 0x04 /* Kill Command (write) */ 103 #define ALI1535_A_HIGH_BIT8 0x04 /* Bit 8 of 10-bit address in */ 104 /* Alert-Response-Address */ 105 /* (read) */ 106 107 #define ALI1535_D_HI_MASK 0x03 /* Mask for isolating bits 9-8 */ 108 /* of 10-bit address in I2C */ 109 /* Read Command */ 110 111 /* ALI1535 status register bits */ 112 #define ALI1535_STS_IDLE 0x04 113 #define ALI1535_STS_BUSY 0x08 /* host busy */ 114 #define ALI1535_STS_DONE 0x10 /* transaction complete */ 115 #define ALI1535_STS_DEV 0x20 /* device error */ 116 #define ALI1535_STS_BUSERR 0x40 /* bus error */ 117 #define ALI1535_STS_FAIL 0x80 /* failed bus transaction */ 118 #define ALI1535_STS_ERR 0xE0 /* all the bad error bits */ 119 120 #define ALI1535_BLOCK_CLR 0x04 /* reset block data index */ 121 122 /* ALI1535 device address register bits */ 123 #define ALI1535_RD_ADDR 0x01 /* Read/Write Bit in Device */ 124 /* Address field */ 125 /* -> Write = 0 */ 126 /* -> Read = 1 */ 127 #define ALI1535_SMBIO_EN 0x04 /* SMB I/O Space enable */ 128 129 static struct pci_driver ali1535_driver; 130 static unsigned long ali1535_smba; 131 static unsigned short ali1535_offset; 132 133 /* Detect whether a ALI1535 can be found, and initialize it, where necessary. 134 Note the differences between kernels with the old PCI BIOS interface and 135 newer kernels with the real PCI interface. In compat.h some things are 136 defined to make the transition easier. */ 137 static int ali1535_setup(struct pci_dev *dev) 138 { 139 int retval; 140 unsigned char temp; 141 142 /* Check the following things: 143 - SMB I/O address is initialized 144 - Device is enabled 145 - We can use the addresses 146 */ 147 148 retval = pci_enable_device(dev); 149 if (retval) { 150 dev_err(&dev->dev, "ALI1535_smb can't enable device\n"); 151 goto exit; 152 } 153 154 /* Determine the address of the SMBus area */ 155 pci_read_config_word(dev, SMBBA, &ali1535_offset); 156 dev_dbg(&dev->dev, "ALI1535_smb is at offset 0x%04x\n", ali1535_offset); 157 ali1535_offset &= (0xffff & ~(ALI1535_SMB_IOSIZE - 1)); 158 if (ali1535_offset == 0) { 159 dev_warn(&dev->dev, 160 "ALI1535_smb region uninitialized - upgrade BIOS?\n"); 161 retval = -ENODEV; 162 goto exit; 163 } 164 165 if (pci_resource_flags(dev, 0) & IORESOURCE_IO) 166 ali1535_smba = pci_resource_start(dev, 0) + ali1535_offset; 167 else 168 ali1535_smba = ali1535_offset; 169 170 retval = acpi_check_region(ali1535_smba, ALI1535_SMB_IOSIZE, 171 ali1535_driver.name); 172 if (retval) 173 goto exit; 174 175 if (!request_region(ali1535_smba, ALI1535_SMB_IOSIZE, 176 ali1535_driver.name)) { 177 dev_err(&dev->dev, "ALI1535_smb region 0x%lx already in use!\n", 178 ali1535_smba); 179 retval = -EBUSY; 180 goto exit; 181 } 182 183 /* check if whole device is enabled */ 184 pci_read_config_byte(dev, SMBCFG, &temp); 185 if ((temp & ALI1535_SMBIO_EN) == 0) { 186 dev_err(&dev->dev, "SMB device not enabled - upgrade BIOS?\n"); 187 retval = -ENODEV; 188 goto exit_free; 189 } 190 191 /* Is SMB Host controller enabled? */ 192 pci_read_config_byte(dev, SMBHSTCFG, &temp); 193 if ((temp & 1) == 0) { 194 dev_err(&dev->dev, "SMBus controller not enabled - upgrade BIOS?\n"); 195 retval = -ENODEV; 196 goto exit_free; 197 } 198 199 /* set SMB clock to 74KHz as recommended in data sheet */ 200 pci_write_config_byte(dev, SMBCLK, 0x20); 201 202 /* 203 The interrupt routing for SMB is set up in register 0x77 in the 204 1533 ISA Bridge device, NOT in the 7101 device. 205 Don't bother with finding the 1533 device and reading the register. 206 if ((....... & 0x0F) == 1) 207 dev_dbg(&dev->dev, "ALI1535 using Interrupt 9 for SMBus.\n"); 208 */ 209 pci_read_config_byte(dev, SMBREV, &temp); 210 dev_dbg(&dev->dev, "SMBREV = 0x%X\n", temp); 211 dev_dbg(&dev->dev, "ALI1535_smba = 0x%lx\n", ali1535_smba); 212 213 return 0; 214 215 exit_free: 216 release_region(ali1535_smba, ALI1535_SMB_IOSIZE); 217 exit: 218 return retval; 219 } 220 221 static int ali1535_transaction(struct i2c_adapter *adap) 222 { 223 int temp; 224 int result = 0; 225 int timeout = 0; 226 227 dev_dbg(&adap->dev, "Transaction (pre): STS=%02x, TYP=%02x, " 228 "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", 229 inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), 230 inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); 231 232 /* get status */ 233 temp = inb_p(SMBHSTSTS); 234 235 /* Make sure the SMBus host is ready to start transmitting */ 236 /* Check the busy bit first */ 237 if (temp & ALI1535_STS_BUSY) { 238 /* If the host controller is still busy, it may have timed out 239 * in the previous transaction, resulting in a "SMBus Timeout" 240 * printk. I've tried the following to reset a stuck busy bit. 241 * 1. Reset the controller with an KILL command. (this 242 * doesn't seem to clear the controller if an external 243 * device is hung) 244 * 2. Reset the controller and the other SMBus devices with a 245 * T_OUT command. (this clears the host busy bit if an 246 * external device is hung, but it comes back upon a new 247 * access to a device) 248 * 3. Disable and reenable the controller in SMBHSTCFG. Worst 249 * case, nothing seems to work except power reset. 250 */ 251 252 /* Try resetting entire SMB bus, including other devices - This 253 * may not work either - it clears the BUSY bit but then the 254 * BUSY bit may come back on when you try and use the chip 255 * again. If that's the case you are stuck. 256 */ 257 dev_info(&adap->dev, 258 "Resetting entire SMB Bus to clear busy condition (%02x)\n", 259 temp); 260 outb_p(ALI1535_T_OUT, SMBHSTTYP); 261 temp = inb_p(SMBHSTSTS); 262 } 263 264 /* now check the error bits and the busy bit */ 265 if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { 266 /* do a clear-on-write */ 267 outb_p(0xFF, SMBHSTSTS); 268 temp = inb_p(SMBHSTSTS); 269 if (temp & (ALI1535_STS_ERR | ALI1535_STS_BUSY)) { 270 /* This is probably going to be correctable only by a 271 * power reset as one of the bits now appears to be 272 * stuck */ 273 /* This may be a bus or device with electrical problems. */ 274 dev_err(&adap->dev, 275 "SMBus reset failed! (0x%02x) - controller or " 276 "device on bus is probably hung\n", temp); 277 return -EBUSY; 278 } 279 } else { 280 /* check and clear done bit */ 281 if (temp & ALI1535_STS_DONE) 282 outb_p(temp, SMBHSTSTS); 283 } 284 285 /* start the transaction by writing anything to the start register */ 286 outb_p(0xFF, SMBHSTPORT); 287 288 /* We will always wait for a fraction of a second! */ 289 timeout = 0; 290 do { 291 usleep_range(1000, 2000); 292 temp = inb_p(SMBHSTSTS); 293 } while (((temp & ALI1535_STS_BUSY) && !(temp & ALI1535_STS_IDLE)) 294 && (timeout++ < MAX_TIMEOUT)); 295 296 /* If the SMBus is still busy, we give up */ 297 if (timeout > MAX_TIMEOUT) { 298 result = -ETIMEDOUT; 299 dev_err(&adap->dev, "SMBus Timeout!\n"); 300 } 301 302 if (temp & ALI1535_STS_FAIL) { 303 result = -EIO; 304 dev_dbg(&adap->dev, "Error: Failed bus transaction\n"); 305 } 306 307 /* Unfortunately the ALI SMB controller maps "no response" and "bus 308 * collision" into a single bit. No response is the usual case so don't 309 * do a printk. This means that bus collisions go unreported. 310 */ 311 if (temp & ALI1535_STS_BUSERR) { 312 result = -ENXIO; 313 dev_dbg(&adap->dev, 314 "Error: no response or bus collision ADD=%02x\n", 315 inb_p(SMBHSTADD)); 316 } 317 318 /* haven't ever seen this */ 319 if (temp & ALI1535_STS_DEV) { 320 result = -EIO; 321 dev_err(&adap->dev, "Error: device error\n"); 322 } 323 324 /* check to see if the "command complete" indication is set */ 325 if (!(temp & ALI1535_STS_DONE)) { 326 result = -ETIMEDOUT; 327 dev_err(&adap->dev, "Error: command never completed\n"); 328 } 329 330 dev_dbg(&adap->dev, "Transaction (post): STS=%02x, TYP=%02x, " 331 "CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n", 332 inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD), 333 inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1)); 334 335 /* take consequent actions for error conditions */ 336 if (!(temp & ALI1535_STS_DONE)) { 337 /* issue "kill" to reset host controller */ 338 outb_p(ALI1535_KILL, SMBHSTTYP); 339 outb_p(0xFF, SMBHSTSTS); 340 } else if (temp & ALI1535_STS_ERR) { 341 /* issue "timeout" to reset all devices on bus */ 342 outb_p(ALI1535_T_OUT, SMBHSTTYP); 343 outb_p(0xFF, SMBHSTSTS); 344 } 345 346 return result; 347 } 348 349 /* Return negative errno on error. */ 350 static s32 ali1535_access(struct i2c_adapter *adap, u16 addr, 351 unsigned short flags, char read_write, u8 command, 352 int size, union i2c_smbus_data *data) 353 { 354 int i, len; 355 int temp; 356 int timeout; 357 s32 result = 0; 358 359 /* make sure SMBus is idle */ 360 temp = inb_p(SMBHSTSTS); 361 for (timeout = 0; 362 (timeout < MAX_TIMEOUT) && !(temp & ALI1535_STS_IDLE); 363 timeout++) { 364 usleep_range(1000, 2000); 365 temp = inb_p(SMBHSTSTS); 366 } 367 if (timeout >= MAX_TIMEOUT) 368 dev_warn(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp); 369 370 /* clear status register (clear-on-write) */ 371 outb_p(0xFF, SMBHSTSTS); 372 373 switch (size) { 374 case I2C_SMBUS_QUICK: 375 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 376 SMBHSTADD); 377 size = ALI1535_QUICK; 378 outb_p(size, SMBHSTTYP); /* output command */ 379 break; 380 case I2C_SMBUS_BYTE: 381 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 382 SMBHSTADD); 383 size = ALI1535_BYTE; 384 outb_p(size, SMBHSTTYP); /* output command */ 385 if (read_write == I2C_SMBUS_WRITE) 386 outb_p(command, SMBHSTCMD); 387 break; 388 case I2C_SMBUS_BYTE_DATA: 389 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 390 SMBHSTADD); 391 size = ALI1535_BYTE_DATA; 392 outb_p(size, SMBHSTTYP); /* output command */ 393 outb_p(command, SMBHSTCMD); 394 if (read_write == I2C_SMBUS_WRITE) 395 outb_p(data->byte, SMBHSTDAT0); 396 break; 397 case I2C_SMBUS_WORD_DATA: 398 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 399 SMBHSTADD); 400 size = ALI1535_WORD_DATA; 401 outb_p(size, SMBHSTTYP); /* output command */ 402 outb_p(command, SMBHSTCMD); 403 if (read_write == I2C_SMBUS_WRITE) { 404 outb_p(data->word & 0xff, SMBHSTDAT0); 405 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); 406 } 407 break; 408 case I2C_SMBUS_BLOCK_DATA: 409 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01), 410 SMBHSTADD); 411 size = ALI1535_BLOCK_DATA; 412 outb_p(size, SMBHSTTYP); /* output command */ 413 outb_p(command, SMBHSTCMD); 414 if (read_write == I2C_SMBUS_WRITE) { 415 len = data->block[0]; 416 if (len < 0) { 417 len = 0; 418 data->block[0] = len; 419 } 420 if (len > 32) { 421 len = 32; 422 data->block[0] = len; 423 } 424 outb_p(len, SMBHSTDAT0); 425 /* Reset SMBBLKDAT */ 426 outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); 427 for (i = 1; i <= len; i++) 428 outb_p(data->block[i], SMBBLKDAT); 429 } 430 break; 431 default: 432 dev_warn(&adap->dev, "Unsupported transaction %d\n", size); 433 result = -EOPNOTSUPP; 434 goto EXIT; 435 } 436 437 result = ali1535_transaction(adap); 438 if (result) 439 goto EXIT; 440 441 if ((read_write == I2C_SMBUS_WRITE) || (size == ALI1535_QUICK)) { 442 result = 0; 443 goto EXIT; 444 } 445 446 switch (size) { 447 case ALI1535_BYTE: /* Result put in SMBHSTDAT0 */ 448 data->byte = inb_p(SMBHSTDAT0); 449 break; 450 case ALI1535_BYTE_DATA: 451 data->byte = inb_p(SMBHSTDAT0); 452 break; 453 case ALI1535_WORD_DATA: 454 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); 455 break; 456 case ALI1535_BLOCK_DATA: 457 len = inb_p(SMBHSTDAT0); 458 if (len > 32) 459 len = 32; 460 data->block[0] = len; 461 /* Reset SMBBLKDAT */ 462 outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP); 463 for (i = 1; i <= data->block[0]; i++) { 464 data->block[i] = inb_p(SMBBLKDAT); 465 dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n", 466 len, i, data->block[i]); 467 } 468 break; 469 } 470 EXIT: 471 return result; 472 } 473 474 475 static u32 ali1535_func(struct i2c_adapter *adapter) 476 { 477 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 478 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 479 I2C_FUNC_SMBUS_BLOCK_DATA; 480 } 481 482 static const struct i2c_algorithm smbus_algorithm = { 483 .smbus_xfer = ali1535_access, 484 .functionality = ali1535_func, 485 }; 486 487 static struct i2c_adapter ali1535_adapter = { 488 .owner = THIS_MODULE, 489 .class = I2C_CLASS_HWMON | I2C_CLASS_SPD, 490 .algo = &smbus_algorithm, 491 }; 492 493 static const struct pci_device_id ali1535_ids[] = { 494 { PCI_DEVICE(PCI_VENDOR_ID_AL, PCI_DEVICE_ID_AL_M7101) }, 495 { }, 496 }; 497 498 MODULE_DEVICE_TABLE(pci, ali1535_ids); 499 500 static int ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id) 501 { 502 if (ali1535_setup(dev)) { 503 dev_warn(&dev->dev, 504 "ALI1535 not detected, module not inserted.\n"); 505 return -ENODEV; 506 } 507 508 /* set up the sysfs linkage to our parent device */ 509 ali1535_adapter.dev.parent = &dev->dev; 510 511 snprintf(ali1535_adapter.name, sizeof(ali1535_adapter.name), 512 "SMBus ALI1535 adapter at %04x", ali1535_offset); 513 return i2c_add_adapter(&ali1535_adapter); 514 } 515 516 static void ali1535_remove(struct pci_dev *dev) 517 { 518 i2c_del_adapter(&ali1535_adapter); 519 release_region(ali1535_smba, ALI1535_SMB_IOSIZE); 520 } 521 522 static struct pci_driver ali1535_driver = { 523 .name = "ali1535_smbus", 524 .id_table = ali1535_ids, 525 .probe = ali1535_probe, 526 .remove = ali1535_remove, 527 }; 528 529 module_pci_driver(ali1535_driver); 530 531 MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl>, " 532 "Philip Edelbrock <phil@netroedge.com>, " 533 "Mark D. Studebaker <mdsxyz123@yahoo.com> " 534 "and Dan Eaton <dan.eaton@rocketlogix.com>"); 535 MODULE_DESCRIPTION("ALI1535 SMBus driver"); 536 MODULE_LICENSE("GPL"); 537