[PATCH] i2c-i801: I2C patch for Intel ESB2
[linux-2.6] / drivers / i2c / busses / i2c-i801.c
1 /*
2     i801.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>, and Mark D. Studebaker
6     <mdsxyz123@yahoo.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     SUPPORTED DEVICES   PCI ID
25     82801AA             2413           
26     82801AB             2423           
27     82801BA             2443           
28     82801CA/CAM         2483           
29     82801DB             24C3   (HW PEC supported, 32 byte buffer not supported)
30     82801EB             24D3   (HW PEC supported, 32 byte buffer not supported)
31     6300ESB             25A4
32     ICH6                266A
33     ICH7                27DA
34     ESB2                269B
35     This driver supports several versions of Intel's I/O Controller Hubs (ICH).
36     For SMBus support, they are similar to the PIIX4 and are part
37     of Intel's '810' and other chipsets.
38     See the doc/busses/i2c-i801 file for details.
39     I2C Block Read and Process Call are not supported.
40 */
41
42 /* Note: we assume there can only be one I801, with one SMBus interface */
43
44 #include <linux/config.h>
45 #include <linux/module.h>
46 #include <linux/pci.h>
47 #include <linux/kernel.h>
48 #include <linux/stddef.h>
49 #include <linux/delay.h>
50 #include <linux/sched.h>
51 #include <linux/ioport.h>
52 #include <linux/init.h>
53 #include <linux/i2c.h>
54 #include <asm/io.h>
55
56 #ifdef I2C_FUNC_SMBUS_BLOCK_DATA_PEC
57 #define HAVE_PEC
58 #endif
59
60 /* I801 SMBus address offsets */
61 #define SMBHSTSTS       (0 + i801_smba)
62 #define SMBHSTCNT       (2 + i801_smba)
63 #define SMBHSTCMD       (3 + i801_smba)
64 #define SMBHSTADD       (4 + i801_smba)
65 #define SMBHSTDAT0      (5 + i801_smba)
66 #define SMBHSTDAT1      (6 + i801_smba)
67 #define SMBBLKDAT       (7 + i801_smba)
68 #define SMBPEC          (8 + i801_smba) /* ICH4 only */
69 #define SMBAUXSTS       (12 + i801_smba)        /* ICH4 only */
70 #define SMBAUXCTL       (13 + i801_smba)        /* ICH4 only */
71
72 /* PCI Address Constants */
73 #define SMBBA           0x020
74 #define SMBHSTCFG       0x040
75 #define SMBREV          0x008
76
77 /* Host configuration bits for SMBHSTCFG */
78 #define SMBHSTCFG_HST_EN        1
79 #define SMBHSTCFG_SMB_SMI_EN    2
80 #define SMBHSTCFG_I2C_EN        4
81
82 /* Other settings */
83 #define MAX_TIMEOUT             100
84 #define ENABLE_INT9             0       /* set to 0x01 to enable - untested */
85
86 /* I801 command constants */
87 #define I801_QUICK              0x00
88 #define I801_BYTE               0x04
89 #define I801_BYTE_DATA          0x08
90 #define I801_WORD_DATA          0x0C
91 #define I801_PROC_CALL          0x10    /* later chips only, unimplemented */
92 #define I801_BLOCK_DATA         0x14
93 #define I801_I2C_BLOCK_DATA     0x18    /* unimplemented */
94 #define I801_BLOCK_LAST         0x34
95 #define I801_I2C_BLOCK_LAST     0x38    /* unimplemented */
96 #define I801_START              0x40
97 #define I801_PEC_EN             0x80    /* ICH4 only */
98
99 /* insmod parameters */
100
101 /* If force_addr is set to anything different from 0, we forcibly enable
102    the I801 at the given address. VERY DANGEROUS! */
103 static u16 force_addr;
104 module_param(force_addr, ushort, 0);
105 MODULE_PARM_DESC(force_addr,
106                  "Forcibly enable the I801 at the given address. "
107                  "EXTREMELY DANGEROUS!");
108
109 static int i801_transaction(void);
110 static int i801_block_transaction(union i2c_smbus_data *data,
111                                   char read_write, int command);
112
113 static unsigned short i801_smba;
114 static struct pci_dev *I801_dev;
115 static int isich4;
116
117 static int i801_setup(struct pci_dev *dev)
118 {
119         int error_return = 0;
120         unsigned char temp;
121
122         /* Note: we keep on searching until we have found 'function 3' */
123         if(PCI_FUNC(dev->devfn) != 3)
124                 return -ENODEV;
125
126         I801_dev = dev;
127         if ((dev->device == PCI_DEVICE_ID_INTEL_82801DB_3) ||
128             (dev->device == PCI_DEVICE_ID_INTEL_82801EB_3) ||
129             (dev->device == PCI_DEVICE_ID_INTEL_ESB_4))
130                 isich4 = 1;
131         else
132                 isich4 = 0;
133
134         /* Determine the address of the SMBus areas */
135         if (force_addr) {
136                 i801_smba = force_addr & 0xfff0;
137         } else {
138                 pci_read_config_word(I801_dev, SMBBA, &i801_smba);
139                 i801_smba &= 0xfff0;
140                 if(i801_smba == 0) {
141                         dev_err(&dev->dev, "SMB base address uninitialized"
142                                 "- upgrade BIOS or use force_addr=0xaddr\n");
143                         return -ENODEV;
144                 }
145         }
146
147         if (!request_region(i801_smba, (isich4 ? 16 : 8), "i801-smbus")) {
148                 dev_err(&dev->dev, "I801_smb region 0x%x already in use!\n",
149                         i801_smba);
150                 error_return = -EBUSY;
151                 goto END;
152         }
153
154         pci_read_config_byte(I801_dev, SMBHSTCFG, &temp);
155         temp &= ~SMBHSTCFG_I2C_EN;      /* SMBus timing */
156         pci_write_config_byte(I801_dev, SMBHSTCFG, temp);
157
158         /* If force_addr is set, we program the new address here. Just to make
159            sure, we disable the device first. */
160         if (force_addr) {
161                 pci_write_config_byte(I801_dev, SMBHSTCFG, temp & 0xfe);
162                 pci_write_config_word(I801_dev, SMBBA, i801_smba);
163                 pci_write_config_byte(I801_dev, SMBHSTCFG, temp | 0x01);
164                 dev_warn(&dev->dev, "WARNING: I801 SMBus interface set to "
165                         "new address %04x!\n", i801_smba);
166         } else if ((temp & 1) == 0) {
167                 pci_write_config_byte(I801_dev, SMBHSTCFG, temp | 1);
168                 dev_warn(&dev->dev, "enabling SMBus device\n");
169         }
170
171         if (temp & 0x02)
172                 dev_dbg(&dev->dev, "I801 using Interrupt SMI# for SMBus.\n");
173         else
174                 dev_dbg(&dev->dev, "I801 using PCI Interrupt for SMBus.\n");
175
176         pci_read_config_byte(I801_dev, SMBREV, &temp);
177         dev_dbg(&dev->dev, "SMBREV = 0x%X\n", temp);
178         dev_dbg(&dev->dev, "I801_smba = 0x%X\n", i801_smba);
179
180 END:
181         return error_return;
182 }
183
184 static int i801_transaction(void)
185 {
186         int temp;
187         int result = 0;
188         int timeout = 0;
189
190         dev_dbg(&I801_dev->dev, "Transaction (pre): CNT=%02x, CMD=%02x,"
191                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
192                 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
193                 inb_p(SMBHSTDAT1));
194
195         /* Make sure the SMBus host is ready to start transmitting */
196         /* 0x1f = Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
197         if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
198                 dev_dbg(&I801_dev->dev, "SMBus busy (%02x). Resetting... \n",
199                         temp);
200                 outb_p(temp, SMBHSTSTS);
201                 if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
202                         dev_dbg(&I801_dev->dev, "Failed! (%02x)\n", temp);
203                         return -1;
204                 } else {
205                         dev_dbg(&I801_dev->dev, "Successfull!\n");
206                 }
207         }
208
209         outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
210
211         /* We will always wait for a fraction of a second! */
212         do {
213                 msleep(1);
214                 temp = inb_p(SMBHSTSTS);
215         } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
216
217         /* If the SMBus is still busy, we give up */
218         if (timeout >= MAX_TIMEOUT) {
219                 dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
220                 result = -1;
221         }
222
223         if (temp & 0x10) {
224                 result = -1;
225                 dev_dbg(&I801_dev->dev, "Error: Failed bus transaction\n");
226         }
227
228         if (temp & 0x08) {
229                 result = -1;
230                 dev_err(&I801_dev->dev, "Bus collision! SMBus may be locked "
231                         "until next hard reset. (sorry!)\n");
232                 /* Clock stops and slave is stuck in mid-transmission */
233         }
234
235         if (temp & 0x04) {
236                 result = -1;
237                 dev_dbg(&I801_dev->dev, "Error: no response!\n");
238         }
239
240         if ((inb_p(SMBHSTSTS) & 0x1f) != 0x00)
241                 outb_p(inb(SMBHSTSTS), SMBHSTSTS);
242
243         if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
244                 dev_dbg(&I801_dev->dev, "Failed reset at end of transaction"
245                         "(%02x)\n", temp);
246         }
247         dev_dbg(&I801_dev->dev, "Transaction (post): CNT=%02x, CMD=%02x, "
248                 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
249                 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
250                 inb_p(SMBHSTDAT1));
251         return result;
252 }
253
254 /* All-inclusive block transaction function */
255 static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
256                                   int command)
257 {
258         int i, len;
259         int smbcmd;
260         int temp;
261         int result = 0;
262         int timeout;
263         unsigned char hostc, errmask;
264
265         if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
266                 if (read_write == I2C_SMBUS_WRITE) {
267                         /* set I2C_EN bit in configuration register */
268                         pci_read_config_byte(I801_dev, SMBHSTCFG, &hostc);
269                         pci_write_config_byte(I801_dev, SMBHSTCFG,
270                                               hostc | SMBHSTCFG_I2C_EN);
271                 } else {
272                         dev_err(&I801_dev->dev,
273                                 "I2C_SMBUS_I2C_BLOCK_READ not DB!\n");
274                         return -1;
275                 }
276         }
277
278         if (read_write == I2C_SMBUS_WRITE) {
279                 len = data->block[0];
280                 if (len < 1)
281                         len = 1;
282                 if (len > 32)
283                         len = 32;
284                 outb_p(len, SMBHSTDAT0);
285                 outb_p(data->block[1], SMBBLKDAT);
286         } else {
287                 len = 32;       /* max for reads */
288         }
289
290         if(isich4 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
291                 /* set 32 byte buffer */
292         }
293
294         for (i = 1; i <= len; i++) {
295                 if (i == len && read_write == I2C_SMBUS_READ)
296                         smbcmd = I801_BLOCK_LAST;
297                 else
298                         smbcmd = I801_BLOCK_DATA;
299                 outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT);
300
301                 dev_dbg(&I801_dev->dev, "Block (pre %d): CNT=%02x, CMD=%02x, "
302                         "ADD=%02x, DAT0=%02x, BLKDAT=%02x\n", i,
303                         inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
304                         inb_p(SMBHSTDAT0), inb_p(SMBBLKDAT));
305
306                 /* Make sure the SMBus host is ready to start transmitting */
307                 temp = inb_p(SMBHSTSTS);
308                 if (i == 1) {
309                         /* Erronenous conditions before transaction: 
310                          * Byte_Done, Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
311                         errmask=0x9f; 
312                 } else {
313                         /* Erronenous conditions during transaction: 
314                          * Failed, Bus_Err, Dev_Err, Intr */
315                         errmask=0x1e; 
316                 }
317                 if (temp & errmask) {
318                         dev_dbg(&I801_dev->dev, "SMBus busy (%02x). "
319                                 "Resetting... \n", temp);
320                         outb_p(temp, SMBHSTSTS);
321                         if (((temp = inb_p(SMBHSTSTS)) & errmask) != 0x00) {
322                                 dev_err(&I801_dev->dev,
323                                         "Reset failed! (%02x)\n", temp);
324                                 result = -1;
325                                 goto END;
326                         }
327                         if (i != 1) {
328                                 /* if die in middle of block transaction, fail */
329                                 result = -1;
330                                 goto END;
331                         }
332                 }
333
334                 if (i == 1)
335                         outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
336
337                 /* We will always wait for a fraction of a second! */
338                 timeout = 0;
339                 do {
340                         temp = inb_p(SMBHSTSTS);
341                         msleep(1);
342                 }
343                     while ((!(temp & 0x80))
344                            && (timeout++ < MAX_TIMEOUT));
345
346                 /* If the SMBus is still busy, we give up */
347                 if (timeout >= MAX_TIMEOUT) {
348                         result = -1;
349                         dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
350                 }
351
352                 if (temp & 0x10) {
353                         result = -1;
354                         dev_dbg(&I801_dev->dev,
355                                 "Error: Failed bus transaction\n");
356                 } else if (temp & 0x08) {
357                         result = -1;
358                         dev_err(&I801_dev->dev, "Bus collision!\n");
359                 } else if (temp & 0x04) {
360                         result = -1;
361                         dev_dbg(&I801_dev->dev, "Error: no response!\n");
362                 }
363
364                 if (i == 1 && read_write == I2C_SMBUS_READ) {
365                         len = inb_p(SMBHSTDAT0);
366                         if (len < 1)
367                                 len = 1;
368                         if (len > 32)
369                                 len = 32;
370                         data->block[0] = len;
371                 }
372
373                 /* Retrieve/store value in SMBBLKDAT */
374                 if (read_write == I2C_SMBUS_READ)
375                         data->block[i] = inb_p(SMBBLKDAT);
376                 if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
377                         outb_p(data->block[i+1], SMBBLKDAT);
378                 if ((temp & 0x9e) != 0x00)
379                         outb_p(temp, SMBHSTSTS);  /* signals SMBBLKDAT ready */
380
381                 if ((temp = (0x1e & inb_p(SMBHSTSTS))) != 0x00) {
382                         dev_dbg(&I801_dev->dev,
383                                 "Bad status (%02x) at end of transaction\n",
384                                 temp);
385                 }
386                 dev_dbg(&I801_dev->dev, "Block (post %d): CNT=%02x, CMD=%02x, "
387                         "ADD=%02x, DAT0=%02x, BLKDAT=%02x\n", i,
388                         inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
389                         inb_p(SMBHSTDAT0), inb_p(SMBBLKDAT));
390
391                 if (result < 0)
392                         goto END;
393         }
394
395 #ifdef HAVE_PEC
396         if(isich4 && command == I2C_SMBUS_BLOCK_DATA_PEC) {
397                 /* wait for INTR bit as advised by Intel */
398                 timeout = 0;
399                 do {
400                         temp = inb_p(SMBHSTSTS);
401                         msleep(1);
402                 } while ((!(temp & 0x02))
403                            && (timeout++ < MAX_TIMEOUT));
404
405                 if (timeout >= MAX_TIMEOUT) {
406                         dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
407                 }
408                 outb_p(temp, SMBHSTSTS); 
409         }
410 #endif
411         result = 0;
412 END:
413         if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
414                 /* restore saved configuration register value */
415                 pci_write_config_byte(I801_dev, SMBHSTCFG, hostc);
416         }
417         return result;
418 }
419
420 /* Return -1 on error. */
421 static s32 i801_access(struct i2c_adapter * adap, u16 addr,
422                        unsigned short flags, char read_write, u8 command,
423                        int size, union i2c_smbus_data * data)
424 {
425         int hwpec = 0;
426         int block = 0;
427         int ret, xact = 0;
428
429 #ifdef HAVE_PEC
430         if(isich4)
431                 hwpec = (flags & I2C_CLIENT_PEC) != 0;
432 #endif
433
434         switch (size) {
435         case I2C_SMBUS_QUICK:
436                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
437                        SMBHSTADD);
438                 xact = I801_QUICK;
439                 break;
440         case I2C_SMBUS_BYTE:
441                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
442                        SMBHSTADD);
443                 if (read_write == I2C_SMBUS_WRITE)
444                         outb_p(command, SMBHSTCMD);
445                 xact = I801_BYTE;
446                 break;
447         case I2C_SMBUS_BYTE_DATA:
448                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
449                        SMBHSTADD);
450                 outb_p(command, SMBHSTCMD);
451                 if (read_write == I2C_SMBUS_WRITE)
452                         outb_p(data->byte, SMBHSTDAT0);
453                 xact = I801_BYTE_DATA;
454                 break;
455         case I2C_SMBUS_WORD_DATA:
456                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
457                        SMBHSTADD);
458                 outb_p(command, SMBHSTCMD);
459                 if (read_write == I2C_SMBUS_WRITE) {
460                         outb_p(data->word & 0xff, SMBHSTDAT0);
461                         outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
462                 }
463                 xact = I801_WORD_DATA;
464                 break;
465         case I2C_SMBUS_BLOCK_DATA:
466         case I2C_SMBUS_I2C_BLOCK_DATA:
467 #ifdef HAVE_PEC
468         case I2C_SMBUS_BLOCK_DATA_PEC:
469                 if(hwpec && size == I2C_SMBUS_BLOCK_DATA)
470                         size = I2C_SMBUS_BLOCK_DATA_PEC;
471 #endif
472                 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
473                        SMBHSTADD);
474                 outb_p(command, SMBHSTCMD);
475                 block = 1;
476                 break;
477         case I2C_SMBUS_PROC_CALL:
478         default:
479                 dev_err(&I801_dev->dev, "Unsupported transaction %d\n", size);
480                 return -1;
481         }
482
483 #ifdef HAVE_PEC
484         if(isich4 && hwpec) {
485                 if(size != I2C_SMBUS_QUICK &&
486                    size != I2C_SMBUS_I2C_BLOCK_DATA)
487                         outb_p(1, SMBAUXCTL);   /* enable HW PEC */
488         }
489 #endif
490         if(block)
491                 ret = i801_block_transaction(data, read_write, size);
492         else {
493                 outb_p(xact | ENABLE_INT9, SMBHSTCNT);
494                 ret = i801_transaction();
495         }
496
497 #ifdef HAVE_PEC
498         if(isich4 && hwpec) {
499                 if(size != I2C_SMBUS_QUICK &&
500                    size != I2C_SMBUS_I2C_BLOCK_DATA)
501                         outb_p(0, SMBAUXCTL);
502         }
503 #endif
504
505         if(block)
506                 return ret;
507         if(ret)
508                 return -1;
509         if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
510                 return 0;
511
512         switch (xact & 0x7f) {
513         case I801_BYTE: /* Result put in SMBHSTDAT0 */
514         case I801_BYTE_DATA:
515                 data->byte = inb_p(SMBHSTDAT0);
516                 break;
517         case I801_WORD_DATA:
518                 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
519                 break;
520         }
521         return 0;
522 }
523
524
525 static u32 i801_func(struct i2c_adapter *adapter)
526 {
527         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
528             I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
529             I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
530 #ifdef HAVE_PEC
531              | (isich4 ? I2C_FUNC_SMBUS_BLOCK_DATA_PEC |
532                          I2C_FUNC_SMBUS_HWPEC_CALC
533                        : 0)
534 #endif
535             ;
536 }
537
538 static struct i2c_algorithm smbus_algorithm = {
539         .name           = "Non-I2C SMBus adapter",
540         .id             = I2C_ALGO_SMBUS,
541         .smbus_xfer     = i801_access,
542         .functionality  = i801_func,
543 };
544
545 static struct i2c_adapter i801_adapter = {
546         .owner          = THIS_MODULE,
547         .class          = I2C_CLASS_HWMON,
548         .algo           = &smbus_algorithm,
549         .name           = "unset",
550 };
551
552 static struct pci_device_id i801_ids[] = {
553         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
554         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
555         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_2) },
556         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_3) },
557         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_3) },
558         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_3) },
559         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_4) },
560         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_16) },
561         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_17) },
562         { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_17) },
563         { 0, }
564 };
565
566 MODULE_DEVICE_TABLE (pci, i801_ids);
567
568 static int __devinit i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
569 {
570
571         if (i801_setup(dev)) {
572                 dev_warn(&dev->dev,
573                         "I801 not detected, module not inserted.\n");
574                 return -ENODEV;
575         }
576
577         /* set up the driverfs linkage to our parent device */
578         i801_adapter.dev.parent = &dev->dev;
579
580         snprintf(i801_adapter.name, I2C_NAME_SIZE,
581                 "SMBus I801 adapter at %04x", i801_smba);
582         return i2c_add_adapter(&i801_adapter);
583 }
584
585 static void __devexit i801_remove(struct pci_dev *dev)
586 {
587         i2c_del_adapter(&i801_adapter);
588         release_region(i801_smba, (isich4 ? 16 : 8));
589 }
590
591 static struct pci_driver i801_driver = {
592         .name           = "i801_smbus",
593         .id_table       = i801_ids,
594         .probe          = i801_probe,
595         .remove         = __devexit_p(i801_remove),
596 };
597
598 static int __init i2c_i801_init(void)
599 {
600         return pci_register_driver(&i801_driver);
601 }
602
603 static void __exit i2c_i801_exit(void)
604 {
605         pci_unregister_driver(&i801_driver);
606 }
607
608 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
609                 "Philip Edelbrock <phil@netroedge.com>, "
610                 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
611 MODULE_DESCRIPTION("I801 SMBus driver");
612 MODULE_LICENSE("GPL");
613
614 module_init(i2c_i801_init);
615 module_exit(i2c_i801_exit);