2 i2c-i801.c - Part of lm_sensors, Linux kernel modules for hardware
4 Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl>,
5 Philip Edelbrock <phil@netroedge.com>, and Mark D. Studebaker
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.
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.
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.
24 SUPPORTED DEVICES PCI ID
29 82801DB 24C3 (HW PEC supported, 32 byte buffer not supported)
30 82801EB 24D3 (HW PEC supported, 32 byte buffer not supported)
37 This driver supports several versions of Intel's I/O Controller Hubs (ICH).
38 For SMBus support, they are similar to the PIIX4 and are part
39 of Intel's '810' and other chipsets.
40 See the file Documentation/i2c/busses/i2c-i801 for details.
41 I2C Block Read and Process Call are not supported.
44 /* Note: we assume there can only be one I801, with one SMBus interface */
46 #include <linux/module.h>
47 #include <linux/pci.h>
48 #include <linux/kernel.h>
49 #include <linux/stddef.h>
50 #include <linux/delay.h>
51 #include <linux/sched.h>
52 #include <linux/ioport.h>
53 #include <linux/init.h>
54 #include <linux/i2c.h>
57 /* I801 SMBus address offsets */
58 #define SMBHSTSTS (0 + i801_smba)
59 #define SMBHSTCNT (2 + i801_smba)
60 #define SMBHSTCMD (3 + i801_smba)
61 #define SMBHSTADD (4 + i801_smba)
62 #define SMBHSTDAT0 (5 + i801_smba)
63 #define SMBHSTDAT1 (6 + i801_smba)
64 #define SMBBLKDAT (7 + i801_smba)
65 #define SMBPEC (8 + i801_smba) /* ICH4 only */
66 #define SMBAUXSTS (12 + i801_smba) /* ICH4 only */
67 #define SMBAUXCTL (13 + i801_smba) /* ICH4 only */
69 /* PCI Address Constants */
71 #define SMBHSTCFG 0x040
73 /* Host configuration bits for SMBHSTCFG */
74 #define SMBHSTCFG_HST_EN 1
75 #define SMBHSTCFG_SMB_SMI_EN 2
76 #define SMBHSTCFG_I2C_EN 4
79 #define MAX_TIMEOUT 100
80 #define ENABLE_INT9 0 /* set to 0x01 to enable - untested */
82 /* I801 command constants */
83 #define I801_QUICK 0x00
84 #define I801_BYTE 0x04
85 #define I801_BYTE_DATA 0x08
86 #define I801_WORD_DATA 0x0C
87 #define I801_PROC_CALL 0x10 /* later chips only, unimplemented */
88 #define I801_BLOCK_DATA 0x14
89 #define I801_I2C_BLOCK_DATA 0x18 /* unimplemented */
90 #define I801_BLOCK_LAST 0x34
91 #define I801_I2C_BLOCK_LAST 0x38 /* unimplemented */
92 #define I801_START 0x40
93 #define I801_PEC_EN 0x80 /* ICH4 only */
96 static int i801_transaction(void);
97 static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
98 int command, int hwpec);
100 static unsigned long i801_smba;
101 static struct pci_driver i801_driver;
102 static struct pci_dev *I801_dev;
105 static int i801_transaction(void)
111 dev_dbg(&I801_dev->dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
112 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
113 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
116 /* Make sure the SMBus host is ready to start transmitting */
117 /* 0x1f = Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
118 if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
119 dev_dbg(&I801_dev->dev, "SMBus busy (%02x). Resetting...\n",
121 outb_p(temp, SMBHSTSTS);
122 if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
123 dev_dbg(&I801_dev->dev, "Failed! (%02x)\n", temp);
126 dev_dbg(&I801_dev->dev, "Successfull!\n");
130 outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
132 /* We will always wait for a fraction of a second! */
135 temp = inb_p(SMBHSTSTS);
136 } while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
138 /* If the SMBus is still busy, we give up */
139 if (timeout >= MAX_TIMEOUT) {
140 dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
146 dev_dbg(&I801_dev->dev, "Error: Failed bus transaction\n");
151 dev_err(&I801_dev->dev, "Bus collision! SMBus may be locked "
152 "until next hard reset. (sorry!)\n");
153 /* Clock stops and slave is stuck in mid-transmission */
158 dev_dbg(&I801_dev->dev, "Error: no response!\n");
161 if ((inb_p(SMBHSTSTS) & 0x1f) != 0x00)
162 outb_p(inb(SMBHSTSTS), SMBHSTSTS);
164 if ((temp = (0x1f & inb_p(SMBHSTSTS))) != 0x00) {
165 dev_dbg(&I801_dev->dev, "Failed reset at end of transaction "
168 dev_dbg(&I801_dev->dev, "Transaction (post): CNT=%02x, CMD=%02x, "
169 "ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
170 inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
175 /* All-inclusive block transaction function */
176 static int i801_block_transaction(union i2c_smbus_data *data, char read_write,
177 int command, int hwpec)
184 unsigned char hostc, errmask;
186 if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
187 if (read_write == I2C_SMBUS_WRITE) {
188 /* set I2C_EN bit in configuration register */
189 pci_read_config_byte(I801_dev, SMBHSTCFG, &hostc);
190 pci_write_config_byte(I801_dev, SMBHSTCFG,
191 hostc | SMBHSTCFG_I2C_EN);
193 dev_err(&I801_dev->dev,
194 "I2C_SMBUS_I2C_BLOCK_READ not DB!\n");
199 if (read_write == I2C_SMBUS_WRITE) {
200 len = data->block[0];
205 outb_p(len, SMBHSTDAT0);
206 outb_p(data->block[1], SMBBLKDAT);
208 len = 32; /* max for reads */
211 if(isich4 && command != I2C_SMBUS_I2C_BLOCK_DATA) {
212 /* set 32 byte buffer */
215 for (i = 1; i <= len; i++) {
216 if (i == len && read_write == I2C_SMBUS_READ)
217 smbcmd = I801_BLOCK_LAST;
219 smbcmd = I801_BLOCK_DATA;
220 outb_p(smbcmd | ENABLE_INT9, SMBHSTCNT);
222 dev_dbg(&I801_dev->dev, "Block (pre %d): CNT=%02x, CMD=%02x, "
223 "ADD=%02x, DAT0=%02x, BLKDAT=%02x\n", i,
224 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
225 inb_p(SMBHSTDAT0), inb_p(SMBBLKDAT));
227 /* Make sure the SMBus host is ready to start transmitting */
228 temp = inb_p(SMBHSTSTS);
230 /* Erronenous conditions before transaction:
231 * Byte_Done, Failed, Bus_Err, Dev_Err, Intr, Host_Busy */
234 /* Erronenous conditions during transaction:
235 * Failed, Bus_Err, Dev_Err, Intr */
238 if (temp & errmask) {
239 dev_dbg(&I801_dev->dev, "SMBus busy (%02x). "
240 "Resetting...\n", temp);
241 outb_p(temp, SMBHSTSTS);
242 if (((temp = inb_p(SMBHSTSTS)) & errmask) != 0x00) {
243 dev_err(&I801_dev->dev,
244 "Reset failed! (%02x)\n", temp);
249 /* if die in middle of block transaction, fail */
256 outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);
258 /* We will always wait for a fraction of a second! */
262 temp = inb_p(SMBHSTSTS);
264 while ((!(temp & 0x80))
265 && (timeout++ < MAX_TIMEOUT));
267 /* If the SMBus is still busy, we give up */
268 if (timeout >= MAX_TIMEOUT) {
270 dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
275 dev_dbg(&I801_dev->dev,
276 "Error: Failed bus transaction\n");
277 } else if (temp & 0x08) {
279 dev_err(&I801_dev->dev, "Bus collision!\n");
280 } else if (temp & 0x04) {
282 dev_dbg(&I801_dev->dev, "Error: no response!\n");
285 if (i == 1 && read_write == I2C_SMBUS_READ) {
286 len = inb_p(SMBHSTDAT0);
291 data->block[0] = len;
294 /* Retrieve/store value in SMBBLKDAT */
295 if (read_write == I2C_SMBUS_READ)
296 data->block[i] = inb_p(SMBBLKDAT);
297 if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
298 outb_p(data->block[i+1], SMBBLKDAT);
299 if ((temp & 0x9e) != 0x00)
300 outb_p(temp, SMBHSTSTS); /* signals SMBBLKDAT ready */
302 if ((temp = (0x1e & inb_p(SMBHSTSTS))) != 0x00) {
303 dev_dbg(&I801_dev->dev,
304 "Bad status (%02x) at end of transaction\n",
307 dev_dbg(&I801_dev->dev, "Block (post %d): CNT=%02x, CMD=%02x, "
308 "ADD=%02x, DAT0=%02x, BLKDAT=%02x\n", i,
309 inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
310 inb_p(SMBHSTDAT0), inb_p(SMBBLKDAT));
317 /* wait for INTR bit as advised by Intel */
321 temp = inb_p(SMBHSTSTS);
322 } while ((!(temp & 0x02))
323 && (timeout++ < MAX_TIMEOUT));
325 if (timeout >= MAX_TIMEOUT) {
326 dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
328 outb_p(temp, SMBHSTSTS);
332 if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
333 /* restore saved configuration register value */
334 pci_write_config_byte(I801_dev, SMBHSTCFG, hostc);
339 /* Return -1 on error. */
340 static s32 i801_access(struct i2c_adapter * adap, u16 addr,
341 unsigned short flags, char read_write, u8 command,
342 int size, union i2c_smbus_data * data)
348 hwpec = isich4 && (flags & I2C_CLIENT_PEC)
349 && size != I2C_SMBUS_QUICK
350 && size != I2C_SMBUS_I2C_BLOCK_DATA;
353 case I2C_SMBUS_QUICK:
354 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
359 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
361 if (read_write == I2C_SMBUS_WRITE)
362 outb_p(command, SMBHSTCMD);
365 case I2C_SMBUS_BYTE_DATA:
366 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
368 outb_p(command, SMBHSTCMD);
369 if (read_write == I2C_SMBUS_WRITE)
370 outb_p(data->byte, SMBHSTDAT0);
371 xact = I801_BYTE_DATA;
373 case I2C_SMBUS_WORD_DATA:
374 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
376 outb_p(command, SMBHSTCMD);
377 if (read_write == I2C_SMBUS_WRITE) {
378 outb_p(data->word & 0xff, SMBHSTDAT0);
379 outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
381 xact = I801_WORD_DATA;
383 case I2C_SMBUS_BLOCK_DATA:
384 case I2C_SMBUS_I2C_BLOCK_DATA:
385 outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
387 outb_p(command, SMBHSTCMD);
390 case I2C_SMBUS_PROC_CALL:
392 dev_err(&I801_dev->dev, "Unsupported transaction %d\n", size);
396 outb_p(hwpec, SMBAUXCTL); /* enable/disable hardware PEC */
399 ret = i801_block_transaction(data, read_write, size, hwpec);
401 outb_p(xact | ENABLE_INT9, SMBHSTCNT);
402 ret = i801_transaction();
405 /* Some BIOSes don't like it when PEC is enabled at reboot or resume
406 time, so we forcibly disable it after every transaction. */
408 outb_p(0, SMBAUXCTL);
414 if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
417 switch (xact & 0x7f) {
418 case I801_BYTE: /* Result put in SMBHSTDAT0 */
420 data->byte = inb_p(SMBHSTDAT0);
423 data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
430 static u32 i801_func(struct i2c_adapter *adapter)
432 return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
433 I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
434 I2C_FUNC_SMBUS_BLOCK_DATA | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
435 | (isich4 ? I2C_FUNC_SMBUS_HWPEC_CALC : 0);
438 static const struct i2c_algorithm smbus_algorithm = {
439 .smbus_xfer = i801_access,
440 .functionality = i801_func,
443 static struct i2c_adapter i801_adapter = {
444 .owner = THIS_MODULE,
445 .class = I2C_CLASS_HWMON,
446 .algo = &smbus_algorithm,
449 static struct pci_device_id i801_ids[] = {
450 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AA_3) },
451 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801AB_3) },
452 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801BA_2) },
453 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801CA_3) },
454 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_3) },
455 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801EB_3) },
456 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB_4) },
457 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH6_16) },
458 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH7_17) },
459 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ESB2_17) },
460 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH8_5) },
461 { PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH9_6) },
465 MODULE_DEVICE_TABLE (pci, i801_ids);
467 static int __devinit i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
473 switch (dev->device) {
474 case PCI_DEVICE_ID_INTEL_82801DB_3:
475 case PCI_DEVICE_ID_INTEL_82801EB_3:
476 case PCI_DEVICE_ID_INTEL_ESB_4:
477 case PCI_DEVICE_ID_INTEL_ICH6_16:
478 case PCI_DEVICE_ID_INTEL_ICH7_17:
479 case PCI_DEVICE_ID_INTEL_ESB2_17:
480 case PCI_DEVICE_ID_INTEL_ICH8_5:
481 case PCI_DEVICE_ID_INTEL_ICH9_6:
488 err = pci_enable_device(dev);
490 dev_err(&dev->dev, "Failed to enable SMBus PCI device (%d)\n",
495 /* Determine the address of the SMBus area */
496 i801_smba = pci_resource_start(dev, SMBBAR);
498 dev_err(&dev->dev, "SMBus base address uninitialized, "
504 err = pci_request_region(dev, SMBBAR, i801_driver.name);
506 dev_err(&dev->dev, "Failed to request SMBus region "
507 "0x%lx-0x%Lx\n", i801_smba,
508 (unsigned long long)pci_resource_end(dev, SMBBAR));
512 pci_read_config_byte(I801_dev, SMBHSTCFG, &temp);
513 temp &= ~SMBHSTCFG_I2C_EN; /* SMBus timing */
514 if (!(temp & SMBHSTCFG_HST_EN)) {
515 dev_info(&dev->dev, "Enabling SMBus device\n");
516 temp |= SMBHSTCFG_HST_EN;
518 pci_write_config_byte(I801_dev, SMBHSTCFG, temp);
520 if (temp & SMBHSTCFG_SMB_SMI_EN)
521 dev_dbg(&dev->dev, "SMBus using interrupt SMI#\n");
523 dev_dbg(&dev->dev, "SMBus using PCI Interrupt\n");
525 /* set up the driverfs linkage to our parent device */
526 i801_adapter.dev.parent = &dev->dev;
528 snprintf(i801_adapter.name, I2C_NAME_SIZE,
529 "SMBus I801 adapter at %04lx", i801_smba);
530 err = i2c_add_adapter(&i801_adapter);
532 dev_err(&dev->dev, "Failed to add SMBus adapter\n");
538 pci_release_region(dev, SMBBAR);
543 static void __devexit i801_remove(struct pci_dev *dev)
545 i2c_del_adapter(&i801_adapter);
546 pci_release_region(dev, SMBBAR);
548 * do not call pci_disable_device(dev) since it can cause hard hangs on
549 * some systems during power-off (eg. Fujitsu-Siemens Lifebook E8010)
553 static struct pci_driver i801_driver = {
554 .name = "i801_smbus",
555 .id_table = i801_ids,
557 .remove = __devexit_p(i801_remove),
560 static int __init i2c_i801_init(void)
562 return pci_register_driver(&i801_driver);
565 static void __exit i2c_i801_exit(void)
567 pci_unregister_driver(&i801_driver);
570 MODULE_AUTHOR ("Frodo Looijaard <frodol@dds.nl>, "
571 "Philip Edelbrock <phil@netroedge.com>, "
572 "and Mark D. Studebaker <mdsxyz123@yahoo.com>");
573 MODULE_DESCRIPTION("I801 SMBus driver");
574 MODULE_LICENSE("GPL");
576 module_init(i2c_i801_init);
577 module_exit(i2c_i801_exit);