i2c-amd756.c
// SPDX-License-Identifier: GPL-2.0-or-later
/*
Copyright (c) 1999-2002 Merlin Hughes <merlin@merlin.org>
Shamelessly ripped from i2c-piix4.c:
Copyright (c) 1998, 1999 Frodo Looijaard <frodol@dds.nl> and
Philip Edelbrock <phil@netroedge.com>
*/
/*
2002-04-08: Added nForce support. (Csaba Halasz)
2002-10-03: Fixed nForce PnP I/O port. (Michael Steil)
2002-12-28: Rewritten into something that resembles a Linux driver (hch)
2003-11-29: Added back AMD8111 removed by the previous rewrite.
(Philip Pokorny)
*/
/*
Supports AMD756, AMD766, AMD768, AMD8111 and nVidia nForce
Note: we assume there can only be one device, with one SMBus interface.
*/
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/stddef.h>
#include <linux/ioport.h>
#include <linux/i2c.h>
#include <linux/acpi.h>
#include <linux/io.h>
/* AMD756 SMBus address offsets */
#define SMB_ADDR_OFFSET 0xE0
#define SMB_IOSIZE 16
#define SMB_GLOBAL_STATUS (0x0 + amd756_ioport)
#define SMB_GLOBAL_ENABLE (0x2 + amd756_ioport)
#define SMB_HOST_ADDRESS (0x4 + amd756_ioport)
#define SMB_HOST_DATA (0x6 + amd756_ioport)
#define SMB_HOST_COMMAND (0x8 + amd756_ioport)
#define SMB_HOST_BLOCK_DATA (0x9 + amd756_ioport)
#define SMB_HAS_DATA (0xA + amd756_ioport)
#define SMB_HAS_DEVICE_ADDRESS (0xC + amd756_ioport)
#define SMB_HAS_HOST_ADDRESS (0xE + amd756_ioport)
#define SMB_SNOOP_ADDRESS (0xF + amd756_ioport)
/* PCI Address Constants */
/* address of I/O space */
#define SMBBA 0x058 /* mh */
#define SMBBANFORCE 0x014
/* general configuration */
#define SMBGCFG 0x041 /* mh */
/* silicon revision code */
#define SMBREV 0x008
/* Other settings */
#define MAX_TIMEOUT 500
/* AMD756 constants */
#define AMD756_QUICK 0x00
#define AMD756_BYTE 0x01
#define AMD756_BYTE_DATA 0x02
#define AMD756_WORD_DATA 0x03
#define AMD756_PROCESS_CALL 0x04
#define AMD756_BLOCK_DATA 0x05
static struct pci_driver amd756_driver;
static unsigned short amd756_ioport;
/*
SMBUS event = I/O 28-29 bit 11
see E0 for the status bits and enabled in E2
*/
#define GS_ABRT_STS (1 << 0)
#define GS_COL_STS (1 << 1)
#define GS_PRERR_STS (1 << 2)
#define GS_HST_STS (1 << 3)
#define GS_HCYC_STS (1 << 4)
#define GS_TO_STS (1 << 5)
#define GS_SMB_STS (1 << 11)
#define GS_CLEAR_STS (GS_ABRT_STS | GS_COL_STS | GS_PRERR_STS | \
GS_HCYC_STS | GS_TO_STS )
#define GE_CYC_TYPE_MASK (7)
#define GE_HOST_STC (1 << 3)
#define GE_ABORT (1 << 5)
static int amd756_transaction(struct i2c_adapter *adap)
{
int temp;
int result = 0;
int timeout = 0;
dev_dbg(&adap->dev, "Transaction (pre): GS=%04x, GE=%04x, ADD=%04x, "
"DAT=%04x\n", inw_p(SMB_GLOBAL_STATUS),
inw_p(SMB_GLOBAL_ENABLE), inw_p(SMB_HOST_ADDRESS),
inb_p(SMB_HOST_DATA));
/* Make sure the SMBus host is ready to start transmitting */
if ((temp = inw_p(SMB_GLOBAL_STATUS)) & (GS_HST_STS | GS_SMB_STS)) {
dev_dbg(&adap->dev, "SMBus busy (%04x). Waiting...\n", temp);
do {
msleep(1);
temp = inw_p(SMB_GLOBAL_STATUS);
} while ((temp & (GS_HST_STS | GS_SMB_STS)) &&
(timeout++ < MAX_TIMEOUT));
/* If the SMBus is still busy, we give up */
if (timeout > MAX_TIMEOUT) {
dev_dbg(&adap->dev, "Busy wait timeout (%04x)\n", temp);
goto abort;
}
timeout = 0;
}
/* start the transaction by setting the start bit */
outw_p(inw(SMB_GLOBAL_ENABLE) | GE_HOST_STC, SMB_GLOBAL_ENABLE);
/* We will always wait for a fraction of a second! */
do {
msleep(1);
temp = inw_p(SMB_GLOBAL_STATUS);
} while ((temp & GS_HST_STS) && (timeout++ < MAX_TIMEOUT));
/* If the SMBus is still busy, we give up */
if (timeout > MAX_TIMEOUT) {
dev_dbg(&adap->dev, "Completion timeout!\n");
goto abort;
}
if (temp & GS_PRERR_STS) {
result = -ENXIO;
dev_dbg(&adap->dev, "SMBus Protocol error (no response)!\n");
}
if (temp & GS_COL_STS) {
result = -EIO;
dev_warn(&adap->dev, "SMBus collision!\n");
}
if (temp & GS_TO_STS) {
result = -ETIMEDOUT;
dev_dbg(&adap->dev, "SMBus protocol timeout!\n");
}
if (temp & GS_HCYC_STS)
dev_dbg(&adap->dev, "SMBus protocol success!\n");
outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
#ifdef DEBUG
if (((temp = inw_p(SMB_GLOBAL_STATUS)) & GS_CLEAR_STS) != 0x00) {
dev_dbg(&adap->dev,
"Failed reset at end of transaction (%04x)\n", temp);
}
#endif
dev_dbg(&adap->dev,
"Transaction (post): GS=%04x, GE=%04x, ADD=%04x, DAT=%04x\n",
inw_p(SMB_GLOBAL_STATUS), inw_p(SMB_GLOBAL_ENABLE),
inw_p(SMB_HOST_ADDRESS), inb_p(SMB_HOST_DATA));
return result;
abort:
dev_warn(&adap->dev, "Sending abort\n");
outw_p(inw(SMB_GLOBAL_ENABLE) | GE_ABORT, SMB_GLOBAL_ENABLE);
msleep(100);
outw_p(GS_CLEAR_STS, SMB_GLOBAL_STATUS);
return -EIO;
}
/* Return negative errno on error. */
static s32 amd756_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;
int status;
switch (size) {
case I2C_SMBUS_QUICK:
outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMB_HOST_ADDRESS);
size = AMD756_QUICK;
break;
case I2C_SMBUS_BYTE:
outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMB_HOST_ADDRESS);
if (read_write == I2C_SMBUS_WRITE)
outb_p(command, SMB_HOST_DATA);
size = AMD756_BYTE;
break;
case I2C_SMBUS_BYTE_DATA:
outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMB_HOST_ADDRESS);
outb_p(command, SMB_HOST_COMMAND);
if (read_write == I2C_SMBUS_WRITE)
outw_p(data->byte, SMB_HOST_DATA);
size = AMD756_BYTE_DATA;
break;
case I2C_SMBUS_WORD_DATA:
outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMB_HOST_ADDRESS);
outb_p(command, SMB_HOST_COMMAND);
if (read_write == I2C_SMBUS_WRITE)
outw_p(data->word, SMB_HOST_DATA); /* TODO: endian???? */
size = AMD756_WORD_DATA;
break;
case I2C_SMBUS_BLOCK_DATA:
outw_p(((addr & 0x7f) << 1) | (read_write & 0x01),
SMB_HOST_ADDRESS);
outb_p(command, SMB_HOST_COMMAND);
if (read_write == I2C_SMBUS_WRITE) {
len = data->block[0];
if (len < 0)
len = 0;
if (len > 32)
len = 32;
outw_p(len, SMB_HOST_DATA);
/* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */
for (i = 1; i <= len; i++)
outb_p(data->block[i],
SMB_HOST_BLOCK_DATA);
}
size = AMD756_BLOCK_DATA;
break;
default:
dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
return -EOPNOTSUPP;
}
/* How about enabling interrupts... */
outw_p(size & GE_CYC_TYPE_MASK, SMB_GLOBAL_ENABLE);
status = amd756_transaction(adap);
if (status)
return status;
if ((read_write == I2C_SMBUS_WRITE) || (size == AMD756_QUICK))
return 0;
switch (size) {
case AMD756_BYTE:
data->byte = inw_p(SMB_HOST_DATA);
break;
case AMD756_BYTE_DATA:
data->byte = inw_p(SMB_HOST_DATA);
break;
case AMD756_WORD_DATA:
data->word = inw_p(SMB_HOST_DATA); /* TODO: endian???? */
break;
case AMD756_BLOCK_DATA:
data->block[0] = inw_p(SMB_HOST_DATA) & 0x3f;
if(data->block[0] > 32)
data->block[0] = 32;
/* i = inw_p(SMBHSTCNT); Reset SMBBLKDAT */
for (i = 1; i <= data->block[0]; i++)
data->block[i] = inb_p(SMB_HOST_BLOCK_DATA);
break;
}
return 0;
}
static u32 amd756_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 const struct i2c_algorithm smbus_algorithm = {
.smbus_xfer = amd756_access,
.functionality = amd756_func,
};
struct i2c_adapter amd756_smbus = {
.owner = THIS_MODULE,
.class = I2C_CLASS_HWMON,
.algo = &smbus_algorithm,
};
enum chiptype { AMD756, AMD766, AMD768, NFORCE, AMD8111 };
static const char* chipname[] = {
"AMD756", "AMD766", "AMD768",
"nVidia nForce", "AMD8111",
};
static const struct pci_device_id amd756_ids[] = {
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_740B),
.driver_data = AMD756 },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_VIPER_7413),
.driver_data = AMD766 },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_OPUS_7443),
.driver_data = AMD768 },
{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_8111_SMBUS),
.driver_data = AMD8111 },
{ PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NFORCE_SMBUS),
.driver_data = NFORCE },
{ 0, }
};
MODULE_DEVICE_TABLE (pci, amd756_ids);
static int amd756_probe(struct pci_dev *pdev, const struct pci_device_id *id)
{
int nforce = (id->driver_data == NFORCE);
int error;
u8 temp;
if (amd756_ioport) {
dev_err(&pdev->dev, "Only one device supported "
"(you have a strange motherboard, btw)\n");
return -ENODEV;
}
if (nforce) {
if (PCI_FUNC(pdev->devfn) != 1)
return -ENODEV;
pci_read_config_word(pdev, SMBBANFORCE, &amd756_ioport);
amd756_ioport &= 0xfffc;
} else { /* amd */
if (PCI_FUNC(pdev->devfn) != 3)
return -ENODEV;
pci_read_config_byte(pdev, SMBGCFG, &temp);
if ((temp & 128) == 0) {
dev_err(&pdev->dev,
"Error: SMBus controller I/O not enabled!\n");
return -ENODEV;
}
/* Determine the address of the SMBus areas */
/* Technically it is a dword but... */
pci_read_config_word(pdev, SMBBA, &amd756_ioport);
amd756_ioport &= 0xff00;
amd756_ioport += SMB_ADDR_OFFSET;
}
error = acpi_check_region(amd756_ioport, SMB_IOSIZE,
amd756_driver.name);
if (error)
return -ENODEV;
if (!request_region(amd756_ioport, SMB_IOSIZE, amd756_driver.name)) {
dev_err(&pdev->dev, "SMB region 0x%x already in use!\n",
amd756_ioport);
return -ENODEV;
}
pci_read_config_byte(pdev, SMBREV, &temp);
dev_dbg(&pdev->dev, "SMBREV = 0x%X\n", temp);
dev_dbg(&pdev->dev, "AMD756_smba = 0x%X\n", amd756_ioport);
/* set up the sysfs linkage to our parent device */
amd756_smbus.dev.parent = &pdev->dev;
snprintf(amd756_smbus.name, sizeof(amd756_smbus.name),
"SMBus %s adapter at %04x", chipname[id->driver_data],
amd756_ioport);
error = i2c_add_adapter(&amd756_smbus);
if (error)
goto out_err;
return 0;
out_err:
release_region(amd756_ioport, SMB_IOSIZE);
return error;
}
static void amd756_remove(struct pci_dev *dev)
{
i2c_del_adapter(&amd756_smbus);
release_region(amd756_ioport, SMB_IOSIZE);
}
static struct pci_driver amd756_driver = {
.name = "amd756_smbus",
.id_table = amd756_ids,
.probe = amd756_probe,
.remove = amd756_remove,
};
module_pci_driver(amd756_driver);
MODULE_AUTHOR("Merlin Hughes <merlin@merlin.org>");
MODULE_DESCRIPTION("AMD756/766/768/8111 and nVidia nForce SMBus driver");
MODULE_LICENSE("GPL");
EXPORT_SYMBOL(amd756_smbus);