https://github.com/torvalds/linux
Tip revision: 7705a8792b0fc82fd7d4dd923724606bbfd9fb20 authored by Linus Torvalds on 20 March 2006, 05:53:29 UTC
Linux 2.6.16
Linux 2.6.16
Tip revision: 7705a87
i2c-piix4.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
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!");
/* If fix_hstcfg is set to anything different from 0, we reset one of the
registers to be a valid value. */
static int fix_hstcfg;
module_param (fix_hstcfg, int, 0);
MODULE_PARM_DESC(fix_hstcfg,
"Fix config register. Needed on some boards (Force CPCI735).");
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 Laptop 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);
/* Some BIOS will set up the chipset incorrectly and leave a register
in an undefined state (causing I2C to act very strangely). */
if (temp & 0x02) {
if (fix_hstcfg) {
dev_info(&PIIX4_dev->dev, "Working around buggy BIOS "
"(I2C)\n");
temp &= 0xfd;
pci_write_config_byte(PIIX4_dev, SMBHSTCFG, temp);
} else {
dev_info(&PIIX4_dev->dev, "Unusual config register "
"value\n");
dev_info(&PIIX4_dev->dev, "Try using fix_hstcfg=1 if "
"you experience problems\n");
}
}
/* 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)
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_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_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);