1 /* 2 i2c-viapro.c - Part of lm_sensors, Linux kernel modules for hardware 3 monitoring 4 Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl>, 5 Philip Edelbrock <phil@netroedge.com>, Kyösti Mälkki <kmalkki@cc.hut.fi>, 6 Mark D. Studebaker <mdsxyz123@yahoo.com> 7 Copyright (C) 2005 - 2008 Jean Delvare <khali@linux-fr.org> 8 9 This program is free software; you can redistribute it and/or modify 10 it under the terms of the GNU General Public License as published by 11 the Free Software Foundation; either version 2 of the License, or 12 (at your option) any later version. 13 14 This program is distributed in the hope that it will be useful, 15 but WITHOUT ANY WARRANTY; without even the implied warranty of 16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 GNU General Public License for more details. 18 19 You should have received a copy of the GNU General Public License 20 along with this program; if not, write to the Free Software 21 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 22 */ 23 24 /* 25 Supports the following VIA south bridges: 26 27 Chip name PCI ID REV I2C block 28 VT82C596A 0x3050 no 29 VT82C596B 0x3051 no 30 VT82C686A 0x3057 0x30 no 31 VT82C686B 0x3057 0x40 yes 32 VT8231 0x8235 no? 33 VT8233 0x3074 yes 34 VT8233A 0x3147 yes? 35 VT8235 0x3177 yes 36 VT8237R 0x3227 yes 37 VT8237A 0x3337 yes 38 VT8237S 0x3372 yes 39 VT8251 0x3287 yes 40 CX700 0x8324 yes 41 42 Note: we assume there can only be one device, with one SMBus interface. 43 */ 44 45 #include <linux/module.h> 46 #include <linux/delay.h> 47 #include <linux/pci.h> 48 #include <linux/kernel.h> 49 #include <linux/stddef.h> 50 #include <linux/ioport.h> 51 #include <linux/i2c.h> 52 #include <linux/init.h> 53 #include <asm/io.h> 54 55 static struct pci_dev *vt596_pdev; 56 57 #define SMBBA1 0x90 58 #define SMBBA2 0x80 59 #define SMBBA3 0xD0 60 61 /* SMBus address offsets */ 62 static unsigned short vt596_smba; 63 #define SMBHSTSTS (vt596_smba + 0) 64 #define SMBHSTCNT (vt596_smba + 2) 65 #define SMBHSTCMD (vt596_smba + 3) 66 #define SMBHSTADD (vt596_smba + 4) 67 #define SMBHSTDAT0 (vt596_smba + 5) 68 #define SMBHSTDAT1 (vt596_smba + 6) 69 #define SMBBLKDAT (vt596_smba + 7) 70 71 /* PCI Address Constants */ 72 73 /* SMBus data in configuration space can be found in two places, 74 We try to select the better one */ 75 76 static unsigned short SMBHSTCFG = 0xD2; 77 78 /* Other settings */ 79 #define MAX_TIMEOUT 500 80 81 /* VT82C596 constants */ 82 #define VT596_QUICK 0x00 83 #define VT596_BYTE 0x04 84 #define VT596_BYTE_DATA 0x08 85 #define VT596_WORD_DATA 0x0C 86 #define VT596_BLOCK_DATA 0x14 87 #define VT596_I2C_BLOCK_DATA 0x34 88 89 90 /* If force is set to anything different from 0, we forcibly enable the 91 VT596. DANGEROUS! */ 92 static int force; 93 module_param(force, bool, 0); 94 MODULE_PARM_DESC(force, "Forcibly enable the SMBus. DANGEROUS!"); 95 96 /* If force_addr is set to anything different from 0, we forcibly enable 97 the VT596 at the given address. VERY DANGEROUS! */ 98 static u16 force_addr; 99 module_param(force_addr, ushort, 0); 100 MODULE_PARM_DESC(force_addr, 101 "Forcibly enable the SMBus at the given address. " 102 "EXTREMELY DANGEROUS!"); 103 104 105 static struct pci_driver vt596_driver; 106 static struct i2c_adapter vt596_adapter; 107 108 #define FEATURE_I2CBLOCK (1<<0) 109 static unsigned int vt596_features; 110 111 #ifdef DEBUG 112 static void vt596_dump_regs(const char *msg, u8 size) 113 { 114 dev_dbg(&vt596_adapter.dev, "%s: STS=%02x CNT=%02x CMD=%02x ADD=%02x " 115 "DAT=%02x,%02x\n", msg, inb_p(SMBHSTSTS), inb_p(SMBHSTCNT), 116 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), 117 inb_p(SMBHSTDAT1)); 118 119 if (size == VT596_BLOCK_DATA 120 || size == VT596_I2C_BLOCK_DATA) { 121 int i; 122 123 dev_dbg(&vt596_adapter.dev, "BLK="); 124 for (i = 0; i < I2C_SMBUS_BLOCK_MAX / 2; i++) 125 printk("%02x,", inb_p(SMBBLKDAT)); 126 printk("\n"); 127 dev_dbg(&vt596_adapter.dev, " "); 128 for (; i < I2C_SMBUS_BLOCK_MAX - 1; i++) 129 printk("%02x,", inb_p(SMBBLKDAT)); 130 printk("%02x\n", inb_p(SMBBLKDAT)); 131 } 132 } 133 #else 134 static inline void vt596_dump_regs(const char *msg, u8 size) { } 135 #endif 136 137 /* Return -1 on error, 0 on success */ 138 static int vt596_transaction(u8 size) 139 { 140 int temp; 141 int result = 0; 142 int timeout = 0; 143 144 vt596_dump_regs("Transaction (pre)", size); 145 146 /* Make sure the SMBus host is ready to start transmitting */ 147 if ((temp = inb_p(SMBHSTSTS)) & 0x1F) { 148 dev_dbg(&vt596_adapter.dev, "SMBus busy (0x%02x). " 149 "Resetting...\n", temp); 150 151 outb_p(temp, SMBHSTSTS); 152 if ((temp = inb_p(SMBHSTSTS)) & 0x1F) { 153 dev_err(&vt596_adapter.dev, "SMBus reset failed! " 154 "(0x%02x)\n", temp); 155 return -1; 156 } 157 } 158 159 /* Start the transaction by setting bit 6 */ 160 outb_p(0x40 | size, SMBHSTCNT); 161 162 /* We will always wait for a fraction of a second */ 163 do { 164 msleep(1); 165 temp = inb_p(SMBHSTSTS); 166 } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT)); 167 168 /* If the SMBus is still busy, we give up */ 169 if (timeout >= MAX_TIMEOUT) { 170 result = -1; 171 dev_err(&vt596_adapter.dev, "SMBus timeout!\n"); 172 } 173 174 if (temp & 0x10) { 175 result = -1; 176 dev_err(&vt596_adapter.dev, "Transaction failed (0x%02x)\n", 177 size); 178 } 179 180 if (temp & 0x08) { 181 result = -1; 182 dev_err(&vt596_adapter.dev, "SMBus collision!\n"); 183 } 184 185 if (temp & 0x04) { 186 int read = inb_p(SMBHSTADD) & 0x01; 187 result = -1; 188 /* The quick and receive byte commands are used to probe 189 for chips, so errors are expected, and we don't want 190 to frighten the user. */ 191 if (!((size == VT596_QUICK && !read) || 192 (size == VT596_BYTE && read))) 193 dev_err(&vt596_adapter.dev, "Transaction error!\n"); 194 } 195 196 /* Resetting status register */ 197 if (temp & 0x1F) 198 outb_p(temp, SMBHSTSTS); 199 200 vt596_dump_regs("Transaction (post)", size); 201 202 return result; 203 } 204 205 /* Return -1 on error, 0 on success */ 206 static s32 vt596_access(struct i2c_adapter *adap, u16 addr, 207 unsigned short flags, char read_write, u8 command, 208 int size, union i2c_smbus_data *data) 209 { 210 int i; 211 212 switch (size) { 213 case I2C_SMBUS_QUICK: 214 size = VT596_QUICK; 215 break; 216 case I2C_SMBUS_BYTE: 217 if (read_write == I2C_SMBUS_WRITE) 218 outb_p(command, SMBHSTCMD); 219 size = VT596_BYTE; 220 break; 221 case I2C_SMBUS_BYTE_DATA: 222 outb_p(command, SMBHSTCMD); 223 if (read_write == I2C_SMBUS_WRITE) 224 outb_p(data->byte, SMBHSTDAT0); 225 size = VT596_BYTE_DATA; 226 break; 227 case I2C_SMBUS_WORD_DATA: 228 outb_p(command, SMBHSTCMD); 229 if (read_write == I2C_SMBUS_WRITE) { 230 outb_p(data->word & 0xff, SMBHSTDAT0); 231 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); 232 } 233 size = VT596_WORD_DATA; 234 break; 235 case I2C_SMBUS_I2C_BLOCK_DATA: 236 if (!(vt596_features & FEATURE_I2CBLOCK)) 237 goto exit_unsupported; 238 if (read_write == I2C_SMBUS_READ) 239 outb_p(data->block[0], SMBHSTDAT0); 240 /* Fall through */ 241 case I2C_SMBUS_BLOCK_DATA: 242 outb_p(command, SMBHSTCMD); 243 if (read_write == I2C_SMBUS_WRITE) { 244 u8 len = data->block[0]; 245 if (len > I2C_SMBUS_BLOCK_MAX) 246 len = I2C_SMBUS_BLOCK_MAX; 247 outb_p(len, SMBHSTDAT0); 248 inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ 249 for (i = 1; i <= len; i++) 250 outb_p(data->block[i], SMBBLKDAT); 251 } 252 size = (size == I2C_SMBUS_I2C_BLOCK_DATA) ? 253 VT596_I2C_BLOCK_DATA : VT596_BLOCK_DATA; 254 break; 255 default: 256 goto exit_unsupported; 257 } 258 259 outb_p(((addr & 0x7f) << 1) | read_write, SMBHSTADD); 260 261 if (vt596_transaction(size)) /* Error in transaction */ 262 return -1; 263 264 if ((read_write == I2C_SMBUS_WRITE) || (size == VT596_QUICK)) 265 return 0; 266 267 switch (size) { 268 case VT596_BYTE: 269 case VT596_BYTE_DATA: 270 data->byte = inb_p(SMBHSTDAT0); 271 break; 272 case VT596_WORD_DATA: 273 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); 274 break; 275 case VT596_I2C_BLOCK_DATA: 276 case VT596_BLOCK_DATA: 277 data->block[0] = inb_p(SMBHSTDAT0); 278 if (data->block[0] > I2C_SMBUS_BLOCK_MAX) 279 data->block[0] = I2C_SMBUS_BLOCK_MAX; 280 inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ 281 for (i = 1; i <= data->block[0]; i++) 282 data->block[i] = inb_p(SMBBLKDAT); 283 break; 284 } 285 return 0; 286 287 exit_unsupported: 288 dev_warn(&vt596_adapter.dev, "Unsupported command invoked! (0x%02x)\n", 289 size); 290 return -1; 291 } 292 293 static u32 vt596_func(struct i2c_adapter *adapter) 294 { 295 u32 func = I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 296 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 297 I2C_FUNC_SMBUS_BLOCK_DATA; 298 299 if (vt596_features & FEATURE_I2CBLOCK) 300 func |= I2C_FUNC_SMBUS_I2C_BLOCK; 301 return func; 302 } 303 304 static const struct i2c_algorithm smbus_algorithm = { 305 .smbus_xfer = vt596_access, 306 .functionality = vt596_func, 307 }; 308 309 static struct i2c_adapter vt596_adapter = { 310 .owner = THIS_MODULE, 311 .id = I2C_HW_SMBUS_VIA2, 312 .class = I2C_CLASS_HWMON, 313 .algo = &smbus_algorithm, 314 }; 315 316 static int __devinit vt596_probe(struct pci_dev *pdev, 317 const struct pci_device_id *id) 318 { 319 unsigned char temp; 320 int error = -ENODEV; 321 322 /* driver_data might come from user-space, so check it */ 323 if (id->driver_data & 1 || id->driver_data > 0xff) 324 return -EINVAL; 325 326 /* Determine the address of the SMBus areas */ 327 if (force_addr) { 328 vt596_smba = force_addr & 0xfff0; 329 force = 0; 330 goto found; 331 } 332 333 if ((pci_read_config_word(pdev, id->driver_data, &vt596_smba)) || 334 !(vt596_smba & 0x0001)) { 335 /* try 2nd address and config reg. for 596 */ 336 if (id->device == PCI_DEVICE_ID_VIA_82C596_3 && 337 !pci_read_config_word(pdev, SMBBA2, &vt596_smba) && 338 (vt596_smba & 0x0001)) { 339 SMBHSTCFG = 0x84; 340 } else { 341 /* no matches at all */ 342 dev_err(&pdev->dev, "Cannot configure " 343 "SMBus I/O Base address\n"); 344 return -ENODEV; 345 } 346 } 347 348 vt596_smba &= 0xfff0; 349 if (vt596_smba == 0) { 350 dev_err(&pdev->dev, "SMBus base address " 351 "uninitialized - upgrade BIOS or use " 352 "force_addr=0xaddr\n"); 353 return -ENODEV; 354 } 355 356 found: 357 if (!request_region(vt596_smba, 8, vt596_driver.name)) { 358 dev_err(&pdev->dev, "SMBus region 0x%x already in use!\n", 359 vt596_smba); 360 return -ENODEV; 361 } 362 363 pci_read_config_byte(pdev, SMBHSTCFG, &temp); 364 /* If force_addr is set, we program the new address here. Just to make 365 sure, we disable the VT596 first. */ 366 if (force_addr) { 367 pci_write_config_byte(pdev, SMBHSTCFG, temp & 0xfe); 368 pci_write_config_word(pdev, id->driver_data, vt596_smba); 369 pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01); 370 dev_warn(&pdev->dev, "WARNING: SMBus interface set to new " 371 "address 0x%04x!\n", vt596_smba); 372 } else if (!(temp & 0x01)) { 373 if (force) { 374 /* NOTE: This assumes I/O space and other allocations 375 * WERE done by the Bios! Don't complain if your 376 * hardware does weird things after enabling this. 377 * :') Check for Bios updates before resorting to 378 * this. 379 */ 380 pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01); 381 dev_info(&pdev->dev, "Enabling SMBus device\n"); 382 } else { 383 dev_err(&pdev->dev, "SMBUS: Error: Host SMBus " 384 "controller not enabled! - upgrade BIOS or " 385 "use force=1\n"); 386 goto release_region; 387 } 388 } 389 390 dev_dbg(&pdev->dev, "VT596_smba = 0x%X\n", vt596_smba); 391 392 switch (pdev->device) { 393 case PCI_DEVICE_ID_VIA_CX700: 394 case PCI_DEVICE_ID_VIA_8251: 395 case PCI_DEVICE_ID_VIA_8237: 396 case PCI_DEVICE_ID_VIA_8237A: 397 case PCI_DEVICE_ID_VIA_8237S: 398 case PCI_DEVICE_ID_VIA_8235: 399 case PCI_DEVICE_ID_VIA_8233A: 400 case PCI_DEVICE_ID_VIA_8233_0: 401 vt596_features |= FEATURE_I2CBLOCK; 402 break; 403 case PCI_DEVICE_ID_VIA_82C686_4: 404 /* The VT82C686B (rev 0x40) does support I2C block 405 transactions, but the VT82C686A (rev 0x30) doesn't */ 406 if (pdev->revision >= 0x40) 407 vt596_features |= FEATURE_I2CBLOCK; 408 break; 409 } 410 411 vt596_adapter.dev.parent = &pdev->dev; 412 snprintf(vt596_adapter.name, sizeof(vt596_adapter.name), 413 "SMBus Via Pro adapter at %04x", vt596_smba); 414 415 vt596_pdev = pci_dev_get(pdev); 416 if (i2c_add_adapter(&vt596_adapter)) { 417 pci_dev_put(vt596_pdev); 418 vt596_pdev = NULL; 419 } 420 421 /* Always return failure here. This is to allow other drivers to bind 422 * to this pci device. We don't really want to have control over the 423 * pci device, we only wanted to read as few register values from it. 424 */ 425 return -ENODEV; 426 427 release_region: 428 release_region(vt596_smba, 8); 429 return error; 430 } 431 432 static struct pci_device_id vt596_ids[] = { 433 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596_3), 434 .driver_data = SMBBA1 }, 435 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596B_3), 436 .driver_data = SMBBA1 }, 437 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_4), 438 .driver_data = SMBBA1 }, 439 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233_0), 440 .driver_data = SMBBA3 }, 441 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233A), 442 .driver_data = SMBBA3 }, 443 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235), 444 .driver_data = SMBBA3 }, 445 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237), 446 .driver_data = SMBBA3 }, 447 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237A), 448 .driver_data = SMBBA3 }, 449 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237S), 450 .driver_data = SMBBA3 }, 451 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4), 452 .driver_data = SMBBA1 }, 453 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8251), 454 .driver_data = SMBBA3 }, 455 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_CX700), 456 .driver_data = SMBBA3 }, 457 { 0, } 458 }; 459 460 MODULE_DEVICE_TABLE(pci, vt596_ids); 461 462 static struct pci_driver vt596_driver = { 463 .name = "vt596_smbus", 464 .id_table = vt596_ids, 465 .probe = vt596_probe, 466 .dynids.use_driver_data = 1, 467 }; 468 469 static int __init i2c_vt596_init(void) 470 { 471 return pci_register_driver(&vt596_driver); 472 } 473 474 475 static void __exit i2c_vt596_exit(void) 476 { 477 pci_unregister_driver(&vt596_driver); 478 if (vt596_pdev != NULL) { 479 i2c_del_adapter(&vt596_adapter); 480 release_region(vt596_smba, 8); 481 pci_dev_put(vt596_pdev); 482 vt596_pdev = NULL; 483 } 484 } 485 486 MODULE_AUTHOR("Kyosti Malkki <kmalkki@cc.hut.fi>, " 487 "Mark D. Studebaker <mdsxyz123@yahoo.com> and " 488 "Jean Delvare <khali@linux-fr.org>"); 489 MODULE_DESCRIPTION("vt82c596 SMBus driver"); 490 MODULE_LICENSE("GPL"); 491 492 module_init(i2c_vt596_init); 493 module_exit(i2c_vt596_exit); 494