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>, Ky�sti M�lkki <kmalkki@cc.hut.fi>, 6 Mark D. Studebaker <mdsxyz123@yahoo.com> 7 Copyright (C) 2005 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 38 Note: we assume there can only be one device, with one SMBus interface. 39 */ 40 41 #include <linux/module.h> 42 #include <linux/delay.h> 43 #include <linux/pci.h> 44 #include <linux/kernel.h> 45 #include <linux/stddef.h> 46 #include <linux/ioport.h> 47 #include <linux/i2c.h> 48 #include <linux/init.h> 49 #include <asm/io.h> 50 51 static struct pci_dev *vt596_pdev; 52 53 #define SMBBA1 0x90 54 #define SMBBA2 0x80 55 #define SMBBA3 0xD0 56 57 /* SMBus address offsets */ 58 static unsigned short vt596_smba; 59 #define SMBHSTSTS (vt596_smba + 0) 60 #define SMBHSTCNT (vt596_smba + 2) 61 #define SMBHSTCMD (vt596_smba + 3) 62 #define SMBHSTADD (vt596_smba + 4) 63 #define SMBHSTDAT0 (vt596_smba + 5) 64 #define SMBHSTDAT1 (vt596_smba + 6) 65 #define SMBBLKDAT (vt596_smba + 7) 66 67 /* PCI Address Constants */ 68 69 /* SMBus data in configuration space can be found in two places, 70 We try to select the better one */ 71 72 static unsigned short SMBHSTCFG = 0xD2; 73 74 /* Other settings */ 75 #define MAX_TIMEOUT 500 76 77 /* VT82C596 constants */ 78 #define VT596_QUICK 0x00 79 #define VT596_BYTE 0x04 80 #define VT596_BYTE_DATA 0x08 81 #define VT596_WORD_DATA 0x0C 82 #define VT596_BLOCK_DATA 0x14 83 #define VT596_I2C_BLOCK_DATA 0x34 84 85 86 /* If force is set to anything different from 0, we forcibly enable the 87 VT596. DANGEROUS! */ 88 static int force; 89 module_param(force, bool, 0); 90 MODULE_PARM_DESC(force, "Forcibly enable the SMBus. DANGEROUS!"); 91 92 /* If force_addr is set to anything different from 0, we forcibly enable 93 the VT596 at the given address. VERY DANGEROUS! */ 94 static u16 force_addr; 95 module_param(force_addr, ushort, 0); 96 MODULE_PARM_DESC(force_addr, 97 "Forcibly enable the SMBus at the given address. " 98 "EXTREMELY DANGEROUS!"); 99 100 101 static struct pci_driver vt596_driver; 102 static struct i2c_adapter vt596_adapter; 103 104 #define FEATURE_I2CBLOCK (1<<0) 105 static unsigned int vt596_features; 106 107 #ifdef DEBUG 108 static void vt596_dump_regs(const char *msg, u8 size) 109 { 110 dev_dbg(&vt596_adapter.dev, "%s: STS=%02x CNT=%02x CMD=%02x ADD=%02x " 111 "DAT=%02x,%02x\n", msg, inb_p(SMBHSTSTS), inb_p(SMBHSTCNT), 112 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), 113 inb_p(SMBHSTDAT1)); 114 115 if (size == VT596_BLOCK_DATA 116 || size == VT596_I2C_BLOCK_DATA) { 117 int i; 118 119 dev_dbg(&vt596_adapter.dev, "BLK="); 120 for (i = 0; i < I2C_SMBUS_BLOCK_MAX / 2; i++) 121 printk("%02x,", inb_p(SMBBLKDAT)); 122 printk("\n"); 123 dev_dbg(&vt596_adapter.dev, " "); 124 for (; i < I2C_SMBUS_BLOCK_MAX - 1; i++) 125 printk("%02x,", inb_p(SMBBLKDAT)); 126 printk("%02x\n", inb_p(SMBBLKDAT)); 127 } 128 } 129 #else 130 static inline void vt596_dump_regs(const char *msg, u8 size) { } 131 #endif 132 133 /* Return -1 on error, 0 on success */ 134 static int vt596_transaction(u8 size) 135 { 136 int temp; 137 int result = 0; 138 int timeout = 0; 139 140 vt596_dump_regs("Transaction (pre)", size); 141 142 /* Make sure the SMBus host is ready to start transmitting */ 143 if ((temp = inb_p(SMBHSTSTS)) & 0x1F) { 144 dev_dbg(&vt596_adapter.dev, "SMBus busy (0x%02x). " 145 "Resetting... ", temp); 146 147 outb_p(temp, SMBHSTSTS); 148 if ((temp = inb_p(SMBHSTSTS)) & 0x1F) { 149 printk("Failed! (0x%02x)\n", temp); 150 return -1; 151 } else { 152 printk("Successful!\n"); 153 } 154 } 155 156 /* Start the transaction by setting bit 6 */ 157 outb_p(0x40 | (size & 0x3C), SMBHSTCNT); 158 159 /* We will always wait for a fraction of a second */ 160 do { 161 msleep(1); 162 temp = inb_p(SMBHSTSTS); 163 } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT)); 164 165 /* If the SMBus is still busy, we give up */ 166 if (timeout >= MAX_TIMEOUT) { 167 result = -1; 168 dev_err(&vt596_adapter.dev, "SMBus timeout!\n"); 169 } 170 171 if (temp & 0x10) { 172 result = -1; 173 dev_err(&vt596_adapter.dev, "Transaction failed (0x%02x)\n", 174 inb_p(SMBHSTCNT) & 0x3C); 175 } 176 177 if (temp & 0x08) { 178 result = -1; 179 dev_err(&vt596_adapter.dev, "SMBus collision!\n"); 180 } 181 182 if (temp & 0x04) { 183 result = -1; 184 /* Quick commands are used to probe for chips, so 185 errors are expected, and we don't want to frighten the 186 user. */ 187 if ((inb_p(SMBHSTCNT) & 0x3C) != VT596_QUICK) 188 dev_err(&vt596_adapter.dev, "Transaction error!\n"); 189 } 190 191 /* Resetting status register */ 192 if (temp & 0x1F) 193 outb_p(temp, SMBHSTSTS); 194 195 vt596_dump_regs("Transaction (post)", size); 196 197 return result; 198 } 199 200 /* Return -1 on error, 0 on success */ 201 static s32 vt596_access(struct i2c_adapter *adap, u16 addr, 202 unsigned short flags, char read_write, u8 command, 203 int size, union i2c_smbus_data *data) 204 { 205 int i; 206 207 switch (size) { 208 case I2C_SMBUS_QUICK: 209 size = VT596_QUICK; 210 break; 211 case I2C_SMBUS_BYTE: 212 if (read_write == I2C_SMBUS_WRITE) 213 outb_p(command, SMBHSTCMD); 214 size = VT596_BYTE; 215 break; 216 case I2C_SMBUS_BYTE_DATA: 217 outb_p(command, SMBHSTCMD); 218 if (read_write == I2C_SMBUS_WRITE) 219 outb_p(data->byte, SMBHSTDAT0); 220 size = VT596_BYTE_DATA; 221 break; 222 case I2C_SMBUS_WORD_DATA: 223 outb_p(command, SMBHSTCMD); 224 if (read_write == I2C_SMBUS_WRITE) { 225 outb_p(data->word & 0xff, SMBHSTDAT0); 226 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1); 227 } 228 size = VT596_WORD_DATA; 229 break; 230 case I2C_SMBUS_I2C_BLOCK_DATA: 231 if (!(vt596_features & FEATURE_I2CBLOCK)) 232 goto exit_unsupported; 233 if (read_write == I2C_SMBUS_READ) 234 outb_p(I2C_SMBUS_BLOCK_MAX, SMBHSTDAT0); 235 /* Fall through */ 236 case I2C_SMBUS_BLOCK_DATA: 237 outb_p(command, SMBHSTCMD); 238 if (read_write == I2C_SMBUS_WRITE) { 239 u8 len = data->block[0]; 240 if (len > I2C_SMBUS_BLOCK_MAX) 241 len = I2C_SMBUS_BLOCK_MAX; 242 outb_p(len, SMBHSTDAT0); 243 inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ 244 for (i = 1; i <= len; i++) 245 outb_p(data->block[i], SMBBLKDAT); 246 } 247 size = (size == I2C_SMBUS_I2C_BLOCK_DATA) ? 248 VT596_I2C_BLOCK_DATA : VT596_BLOCK_DATA; 249 break; 250 default: 251 goto exit_unsupported; 252 } 253 254 outb_p(((addr & 0x7f) << 1) | read_write, SMBHSTADD); 255 256 if (vt596_transaction(size)) /* Error in transaction */ 257 return -1; 258 259 if ((read_write == I2C_SMBUS_WRITE) || (size == VT596_QUICK)) 260 return 0; 261 262 switch (size) { 263 case VT596_BYTE: 264 case VT596_BYTE_DATA: 265 data->byte = inb_p(SMBHSTDAT0); 266 break; 267 case VT596_WORD_DATA: 268 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8); 269 break; 270 case VT596_I2C_BLOCK_DATA: 271 case VT596_BLOCK_DATA: 272 data->block[0] = inb_p(SMBHSTDAT0); 273 if (data->block[0] > I2C_SMBUS_BLOCK_MAX) 274 data->block[0] = I2C_SMBUS_BLOCK_MAX; 275 inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */ 276 for (i = 1; i <= data->block[0]; i++) 277 data->block[i] = inb_p(SMBBLKDAT); 278 break; 279 } 280 return 0; 281 282 exit_unsupported: 283 dev_warn(&vt596_adapter.dev, "Unsupported command invoked! (0x%02x)\n", 284 size); 285 return -1; 286 } 287 288 static u32 vt596_func(struct i2c_adapter *adapter) 289 { 290 u32 func = I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE | 291 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA | 292 I2C_FUNC_SMBUS_BLOCK_DATA; 293 294 if (vt596_features & FEATURE_I2CBLOCK) 295 func |= I2C_FUNC_SMBUS_I2C_BLOCK; 296 return func; 297 } 298 299 static struct i2c_algorithm smbus_algorithm = { 300 .smbus_xfer = vt596_access, 301 .functionality = vt596_func, 302 }; 303 304 static struct i2c_adapter vt596_adapter = { 305 .owner = THIS_MODULE, 306 .class = I2C_CLASS_HWMON, 307 .algo = &smbus_algorithm, 308 }; 309 310 static int __devinit vt596_probe(struct pci_dev *pdev, 311 const struct pci_device_id *id) 312 { 313 unsigned char temp; 314 int error = -ENODEV; 315 316 /* Determine the address of the SMBus areas */ 317 if (force_addr) { 318 vt596_smba = force_addr & 0xfff0; 319 force = 0; 320 goto found; 321 } 322 323 if ((pci_read_config_word(pdev, id->driver_data, &vt596_smba)) || 324 !(vt596_smba & 0x0001)) { 325 /* try 2nd address and config reg. for 596 */ 326 if (id->device == PCI_DEVICE_ID_VIA_82C596_3 && 327 !pci_read_config_word(pdev, SMBBA2, &vt596_smba) && 328 (vt596_smba & 0x0001)) { 329 SMBHSTCFG = 0x84; 330 } else { 331 /* no matches at all */ 332 dev_err(&pdev->dev, "Cannot configure " 333 "SMBus I/O Base address\n"); 334 return -ENODEV; 335 } 336 } 337 338 vt596_smba &= 0xfff0; 339 if (vt596_smba == 0) { 340 dev_err(&pdev->dev, "SMBus base address " 341 "uninitialized - upgrade BIOS or use " 342 "force_addr=0xaddr\n"); 343 return -ENODEV; 344 } 345 346 found: 347 if (!request_region(vt596_smba, 8, vt596_driver.name)) { 348 dev_err(&pdev->dev, "SMBus region 0x%x already in use!\n", 349 vt596_smba); 350 return -ENODEV; 351 } 352 353 pci_read_config_byte(pdev, SMBHSTCFG, &temp); 354 /* If force_addr is set, we program the new address here. Just to make 355 sure, we disable the VT596 first. */ 356 if (force_addr) { 357 pci_write_config_byte(pdev, SMBHSTCFG, temp & 0xfe); 358 pci_write_config_word(pdev, id->driver_data, vt596_smba); 359 pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01); 360 dev_warn(&pdev->dev, "WARNING: SMBus interface set to new " 361 "address 0x%04x!\n", vt596_smba); 362 } else if (!(temp & 0x01)) { 363 if (force) { 364 /* NOTE: This assumes I/O space and other allocations 365 * WERE done by the Bios! Don't complain if your 366 * hardware does weird things after enabling this. 367 * :') Check for Bios updates before resorting to 368 * this. 369 */ 370 pci_write_config_byte(pdev, SMBHSTCFG, temp | 0x01); 371 dev_info(&pdev->dev, "Enabling SMBus device\n"); 372 } else { 373 dev_err(&pdev->dev, "SMBUS: Error: Host SMBus " 374 "controller not enabled! - upgrade BIOS or " 375 "use force=1\n"); 376 goto release_region; 377 } 378 } 379 380 dev_dbg(&pdev->dev, "VT596_smba = 0x%X\n", vt596_smba); 381 382 switch (pdev->device) { 383 case PCI_DEVICE_ID_VIA_8237: 384 case PCI_DEVICE_ID_VIA_8235: 385 case PCI_DEVICE_ID_VIA_8233A: 386 case PCI_DEVICE_ID_VIA_8233_0: 387 vt596_features |= FEATURE_I2CBLOCK; 388 break; 389 case PCI_DEVICE_ID_VIA_82C686_4: 390 /* The VT82C686B (rev 0x40) does support I2C block 391 transactions, but the VT82C686A (rev 0x30) doesn't */ 392 if (!pci_read_config_byte(pdev, PCI_REVISION_ID, &temp) 393 && temp >= 0x40) 394 vt596_features |= FEATURE_I2CBLOCK; 395 break; 396 } 397 398 vt596_adapter.dev.parent = &pdev->dev; 399 snprintf(vt596_adapter.name, I2C_NAME_SIZE, 400 "SMBus Via Pro adapter at %04x", vt596_smba); 401 402 vt596_pdev = pci_dev_get(pdev); 403 if (i2c_add_adapter(&vt596_adapter)) { 404 pci_dev_put(vt596_pdev); 405 vt596_pdev = NULL; 406 } 407 408 /* Always return failure here. This is to allow other drivers to bind 409 * to this pci device. We don't really want to have control over the 410 * pci device, we only wanted to read as few register values from it. 411 */ 412 return -ENODEV; 413 414 release_region: 415 release_region(vt596_smba, 8); 416 return error; 417 } 418 419 static struct pci_device_id vt596_ids[] = { 420 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596_3), 421 .driver_data = SMBBA1 }, 422 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C596B_3), 423 .driver_data = SMBBA1 }, 424 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_4), 425 .driver_data = SMBBA1 }, 426 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233_0), 427 .driver_data = SMBBA3 }, 428 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233A), 429 .driver_data = SMBBA3 }, 430 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235), 431 .driver_data = SMBBA3 }, 432 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237), 433 .driver_data = SMBBA3 }, 434 { PCI_DEVICE(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8231_4), 435 .driver_data = SMBBA1 }, 436 { 0, } 437 }; 438 439 MODULE_DEVICE_TABLE(pci, vt596_ids); 440 441 static struct pci_driver vt596_driver = { 442 .owner = THIS_MODULE, 443 .name = "vt596_smbus", 444 .id_table = vt596_ids, 445 .probe = vt596_probe, 446 }; 447 448 static int __init i2c_vt596_init(void) 449 { 450 return pci_register_driver(&vt596_driver); 451 } 452 453 454 static void __exit i2c_vt596_exit(void) 455 { 456 pci_unregister_driver(&vt596_driver); 457 if (vt596_pdev != NULL) { 458 i2c_del_adapter(&vt596_adapter); 459 release_region(vt596_smba, 8); 460 pci_dev_put(vt596_pdev); 461 vt596_pdev = NULL; 462 } 463 } 464 465 MODULE_AUTHOR( 466 "Frodo Looijaard <frodol@dds.nl> and " 467 "Philip Edelbrock <phil@netroedge.com>"); 468 MODULE_DESCRIPTION("vt82c596 SMBus driver"); 469 MODULE_LICENSE("GPL"); 470 471 module_init(i2c_vt596_init); 472 module_exit(i2c_vt596_exit); 473