linux/drivers/i2c/busses/i2c-piix4.c
Jean Delvare f9ba6c04ef [PATCH] I2C: i2c-piix4: Document the IBM problem more clearly
Properly document on which systems the i2c-piix4 SMBus driver will
refuse to load. Hopefully this will make it clearer for users, which
were often wondering why their destop or server systems were detected
as laptops.

Closes bug #6429.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2006-06-22 11:10:32 -07:00

472 lines
13 KiB
C

/*
piix4.c - Part of lm_sensors, Linux kernel modules for hardware
monitoring
Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and
Philip Edelbrock <phil@netroedge.com>
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
Supports:
Intel PIIX4, 440MX
Serverworks OSB4, CSB5, CSB6, HT-1000
SMSC Victory66
Note: we assume there can only be one device, with one SMBus interface.
*/
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/stddef.h>
#include <linux/sched.h>
#include <linux/ioport.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/apm_bios.h>
#include <linux/dmi.h>
#include <asm/io.h>
struct sd {
const unsigned short mfr;
const unsigned short dev;
const unsigned char fn;
const char *name;
};
/* PIIX4 SMBus address offsets */
#define SMBHSTSTS (0 + piix4_smba)
#define SMBHSLVSTS (1 + piix4_smba)
#define SMBHSTCNT (2 + piix4_smba)
#define SMBHSTCMD (3 + piix4_smba)
#define SMBHSTADD (4 + piix4_smba)
#define SMBHSTDAT0 (5 + piix4_smba)
#define SMBHSTDAT1 (6 + piix4_smba)
#define SMBBLKDAT (7 + piix4_smba)
#define SMBSLVCNT (8 + piix4_smba)
#define SMBSHDWCMD (9 + piix4_smba)
#define SMBSLVEVT (0xA + piix4_smba)
#define SMBSLVDAT (0xC + piix4_smba)
/* count for request_region */
#define SMBIOSIZE 8
/* PCI Address Constants */
#define SMBBA 0x090
#define SMBHSTCFG 0x0D2
#define SMBSLVC 0x0D3
#define SMBSHDW1 0x0D4
#define SMBSHDW2 0x0D5
#define SMBREV 0x0D6
/* Other settings */
#define MAX_TIMEOUT 500
#define ENABLE_INT9 0
/* PIIX4 constants */
#define PIIX4_QUICK 0x00
#define PIIX4_BYTE 0x04
#define PIIX4_BYTE_DATA 0x08
#define PIIX4_WORD_DATA 0x0C
#define PIIX4_BLOCK_DATA 0x14
/* insmod parameters */
/* If force is set to anything different from 0, we forcibly enable the
PIIX4. DANGEROUS! */
static int force;
module_param (force, int, 0);
MODULE_PARM_DESC(force, "Forcibly enable the PIIX4. DANGEROUS!");
/* If force_addr is set to anything different from 0, we forcibly enable
the PIIX4 at the given address. VERY DANGEROUS! */
static int force_addr;
module_param (force_addr, int, 0);
MODULE_PARM_DESC(force_addr,
"Forcibly enable the PIIX4 at the given address. "
"EXTREMELY DANGEROUS!");
static int piix4_transaction(void);
static unsigned short piix4_smba;
static struct pci_driver piix4_driver;
static struct i2c_adapter piix4_adapter;
static struct dmi_system_id __devinitdata piix4_dmi_table[] = {
{
.ident = "IBM",
.matches = { DMI_MATCH(DMI_SYS_VENDOR, "IBM"), },
},
{ },
};
static int __devinit piix4_setup(struct pci_dev *PIIX4_dev,
const struct pci_device_id *id)
{
unsigned char temp;
/* match up the function */
if (PCI_FUNC(PIIX4_dev->devfn) != id->driver_data)
return -ENODEV;
dev_info(&PIIX4_dev->dev, "Found %s device\n", pci_name(PIIX4_dev));
/* Don't access SMBus on IBM systems which get corrupted eeproms */
if (dmi_check_system(piix4_dmi_table) &&
PIIX4_dev->vendor == PCI_VENDOR_ID_INTEL) {
dev_err(&PIIX4_dev->dev, "IBM system detected; this module "
"may corrupt your serial eeprom! Refusing to load "
"module!\n");
return -EPERM;
}
/* Determine the address of the SMBus areas */
if (force_addr) {
piix4_smba = force_addr & 0xfff0;
force = 0;
} else {
pci_read_config_word(PIIX4_dev, SMBBA, &piix4_smba);
piix4_smba &= 0xfff0;
if(piix4_smba == 0) {
dev_err(&PIIX4_dev->dev, "SMB base address "
"uninitialized - upgrade BIOS or use "
"force_addr=0xaddr\n");
return -ENODEV;
}
}
if (!request_region(piix4_smba, SMBIOSIZE, piix4_driver.name)) {
dev_err(&PIIX4_dev->dev, "SMB region 0x%x already in use!\n",
piix4_smba);
return -ENODEV;
}
pci_read_config_byte(PIIX4_dev, SMBHSTCFG, &temp);
/* If force_addr is set, we program the new address here. Just to make
sure, we disable the PIIX4 first. */
if (force_addr) {
pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp & 0xfe);
pci_write_config_word(PIIX4_dev, SMBBA, piix4_smba);
pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp | 0x01);
dev_info(&PIIX4_dev->dev, "WARNING: SMBus interface set to "
"new address %04x!\n", piix4_smba);
} else if ((temp & 1) == 0) {
if (force) {
/* This should never need to be done, but has been
* noted that many Dell machines have the SMBus
* interface on the PIIX4 disabled!? NOTE: This assumes
* I/O space and other allocations WERE done by the
* Bios! Don't complain if your hardware does weird
* things after enabling this. :') Check for Bios
* updates before resorting to this.
*/
pci_write_config_byte(PIIX4_dev, SMBHSTCFG,
temp | 1);
dev_printk(KERN_NOTICE, &PIIX4_dev->dev,
"WARNING: SMBus interface has been "
"FORCEFULLY ENABLED!\n");
} else {
dev_err(&PIIX4_dev->dev,
"Host SMBus controller not enabled!\n");
release_region(piix4_smba, SMBIOSIZE);
piix4_smba = 0;
return -ENODEV;
}
}
if (((temp & 0x0E) == 8) || ((temp & 0x0E) == 2))
dev_dbg(&PIIX4_dev->dev, "Using Interrupt 9 for SMBus.\n");
else if ((temp & 0x0E) == 0)
dev_dbg(&PIIX4_dev->dev, "Using Interrupt SMI# for SMBus.\n");
else
dev_err(&PIIX4_dev->dev, "Illegal Interrupt configuration "
"(or code out of date)!\n");
pci_read_config_byte(PIIX4_dev, SMBREV, &temp);
dev_dbg(&PIIX4_dev->dev, "SMBREV = 0x%X\n", temp);
dev_dbg(&PIIX4_dev->dev, "SMBA = 0x%X\n", piix4_smba);
return 0;
}
/* Another internally used function */
static int piix4_transaction(void)
{
int temp;
int result = 0;
int timeout = 0;
dev_dbg(&piix4_adapter.dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
inb_p(SMBHSTDAT1));
/* Make sure the SMBus host is ready to start transmitting */
if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
dev_dbg(&piix4_adapter.dev, "SMBus busy (%02x). "
"Resetting...\n", temp);
outb_p(temp, SMBHSTSTS);
if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
dev_err(&piix4_adapter.dev, "Failed! (%02x)\n", temp);
return -1;
} else {
dev_dbg(&piix4_adapter.dev, "Successfull!\n");
}
}
/* start the transaction by setting bit 6 */
outb_p(inb(SMBHSTCNT) | 0x040, SMBHSTCNT);
/* We will always wait for a fraction of a second! (See PIIX4 docs errata) */
do {
msleep(1);
temp = inb_p(SMBHSTSTS);
} while ((temp & 0x01) && (timeout++ < MAX_TIMEOUT));
/* If the SMBus is still busy, we give up */
if (timeout >= MAX_TIMEOUT) {
dev_err(&piix4_adapter.dev, "SMBus Timeout!\n");
result = -1;
}
if (temp & 0x10) {
result = -1;
dev_err(&piix4_adapter.dev, "Error: Failed bus transaction\n");
}
if (temp & 0x08) {
result = -1;
dev_dbg(&piix4_adapter.dev, "Bus collision! SMBus may be "
"locked until next hard reset. (sorry!)\n");
/* Clock stops and slave is stuck in mid-transmission */
}
if (temp & 0x04) {
result = -1;
dev_dbg(&piix4_adapter.dev, "Error: no response!\n");
}
if (inb_p(SMBHSTSTS) != 0x00)
outb_p(inb(SMBHSTSTS), SMBHSTSTS);
if ((temp = inb_p(SMBHSTSTS)) != 0x00) {
dev_err(&piix4_adapter.dev, "Failed reset at end of "
"transaction (%02x)\n", temp);
}
dev_dbg(&piix4_adapter.dev, "Transaction (post): CNT=%02x, CMD=%02x, "
"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTCNT),
inb_p(SMBHSTCMD), inb_p(SMBHSTADD), inb_p(SMBHSTDAT0),
inb_p(SMBHSTDAT1));
return result;
}
/* Return -1 on error. */
static s32 piix4_access(struct i2c_adapter * adap, u16 addr,
unsigned short flags, char read_write,
u8 command, int size, union i2c_smbus_data * data)
{
int i, len;
switch (size) {
case I2C_SMBUS_PROC_CALL:
dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
return -1;
case I2C_SMBUS_QUICK:
outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMBHSTADD);
size = PIIX4_QUICK;
break;
case I2C_SMBUS_BYTE:
outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMBHSTADD);
if (read_write == I2C_SMBUS_WRITE)
outb_p(command, SMBHSTCMD);
size = PIIX4_BYTE;
break;
case I2C_SMBUS_BYTE_DATA:
outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMBHSTADD);
outb_p(command, SMBHSTCMD);
if (read_write == I2C_SMBUS_WRITE)
outb_p(data->byte, SMBHSTDAT0);
size = PIIX4_BYTE_DATA;
break;
case I2C_SMBUS_WORD_DATA:
outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMBHSTADD);
outb_p(command, SMBHSTCMD);
if (read_write == I2C_SMBUS_WRITE) {
outb_p(data->word & 0xff, SMBHSTDAT0);
outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
}
size = PIIX4_WORD_DATA;
break;
case I2C_SMBUS_BLOCK_DATA:
outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMBHSTADD);
outb_p(command, SMBHSTCMD);
if (read_write == I2C_SMBUS_WRITE) {
len = data->block[0];
if (len < 0)
len = 0;
if (len > 32)
len = 32;
outb_p(len, SMBHSTDAT0);
i = inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
for (i = 1; i <= len; i++)
outb_p(data->block[i], SMBBLKDAT);
}
size = PIIX4_BLOCK_DATA;
break;
}
outb_p((size & 0x1C) + (ENABLE_INT9 & 1), SMBHSTCNT);
if (piix4_transaction()) /* Error in transaction */
return -1;
if ((read_write == I2C_SMBUS_WRITE) || (size == PIIX4_QUICK))
return 0;
switch (size) {
case PIIX4_BYTE: /* Where is the result put? I assume here it is in
SMBHSTDAT0 but it might just as well be in the
SMBHSTCMD. No clue in the docs */
data->byte = inb_p(SMBHSTDAT0);
break;
case PIIX4_BYTE_DATA:
data->byte = inb_p(SMBHSTDAT0);
break;
case PIIX4_WORD_DATA:
data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
break;
case PIIX4_BLOCK_DATA:
data->block[0] = inb_p(SMBHSTDAT0);
i = inb_p(SMBHSTCNT); /* Reset SMBBLKDAT */
for (i = 1; i <= data->block[0]; i++)
data->block[i] = inb_p(SMBBLKDAT);
break;
}
return 0;
}
static u32 piix4_func(struct i2c_adapter *adapter)
{
return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
I2C_FUNC_SMBUS_BLOCK_DATA;
}
static struct i2c_algorithm smbus_algorithm = {
.smbus_xfer = piix4_access,
.functionality = piix4_func,
};
static struct i2c_adapter piix4_adapter = {
.owner = THIS_MODULE,
.class = I2C_CLASS_HWMON,
.algo = &smbus_algorithm,
};
static struct pci_device_id piix4_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3),
.driver_data = 3 },
{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP200_SMBUS),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP300_SMBUS),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_OSB4),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_CSB5),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_CSB6),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_HT1000SB),
.driver_data = 0 },
{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443MX_3),
.driver_data = 3 },
{ PCI_DEVICE(PCI_VENDOR_ID_EFAR, PCI_DEVICE_ID_EFAR_SLC90E66_3),
.driver_data = 0 },
{ 0, }
};
MODULE_DEVICE_TABLE (pci, piix4_ids);
static int __devinit piix4_probe(struct pci_dev *dev,
const struct pci_device_id *id)
{
int retval;
retval = piix4_setup(dev, id);
if (retval)
return retval;
/* set up the driverfs linkage to our parent device */
piix4_adapter.dev.parent = &dev->dev;
snprintf(piix4_adapter.name, I2C_NAME_SIZE,
"SMBus PIIX4 adapter at %04x", piix4_smba);
if ((retval = i2c_add_adapter(&piix4_adapter))) {
dev_err(&dev->dev, "Couldn't register adapter!\n");
release_region(piix4_smba, SMBIOSIZE);
piix4_smba = 0;
}
return retval;
}
static void __devexit piix4_remove(struct pci_dev *dev)
{
if (piix4_smba) {
i2c_del_adapter(&piix4_adapter);
release_region(piix4_smba, SMBIOSIZE);
piix4_smba = 0;
}
}
static struct pci_driver piix4_driver = {
.name = "piix4_smbus",
.id_table = piix4_ids,
.probe = piix4_probe,
.remove = __devexit_p(piix4_remove),
};
static int __init i2c_piix4_init(void)
{
return pci_register_driver(&piix4_driver);
}
static void __exit i2c_piix4_exit(void)
{
pci_unregister_driver(&piix4_driver);
}
MODULE_AUTHOR("Frodo Looijaard <frodol@dds.nl> and "
"Philip Edelbrock <phil@netroedge.com>");
MODULE_DESCRIPTION("PIIX4 SMBus driver");
MODULE_LICENSE("GPL");
module_init(i2c_piix4_init);
module_exit(i2c_piix4_exit);