i2c-i801.c

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				/* if die in middle of block transaction, fail */
				result = -1;
				goto END;
			}
		}

		if (i == 1)
			outb_p(inb(SMBHSTCNT) | I801_START, SMBHSTCNT);

		/* We will always wait for a fraction of a second! */
		timeout = 0;
		do {
			temp = inb_p(SMBHSTSTS);
			msleep(1);
		}
		    while ((!(temp & 0x80))
			   && (timeout++ < MAX_TIMEOUT));

		/* If the SMBus is still busy, we give up */
		if (timeout >= MAX_TIMEOUT) {
			result = -1;
			dev_dbg(&I801_dev->dev, "SMBus Timeout!\n");
		}

		if (temp & 0x10) {
			result = -1;
			dev_dbg(&I801_dev->dev,
				"Error: Failed bus transaction\n");
		} else if (temp & 0x08) {
			result = -1;
			dev_err(&I801_dev->dev, "Bus collision!\n");
		} else if (temp & 0x04) {
			result = -1;
			dev_dbg(&I801_dev->dev, "Error: no response!\n");
		}

		if (i == 1 && read_write == I2C_SMBUS_READ) {
			len = inb_p(SMBHSTDAT0);
			if (len < 1)
				len = 1;
			if (len > 32)
				len = 32;
			data->block[0] = len;
		}

		/* Retrieve/store value in SMBBLKDAT */
		if (read_write == I2C_SMBUS_READ)
			data->block[i] = inb_p(SMBBLKDAT);
		if (read_write == I2C_SMBUS_WRITE && i+1 <= len)
			outb_p(data->block[i+1], SMBBLKDAT);
		if ((temp & 0x9e) != 0x00)
			outb_p(temp, SMBHSTSTS);  /* signals SMBBLKDAT ready */

		if ((temp = (0x1e & inb_p(SMBHSTSTS))) != 0x00) {
			dev_dbg(&I801_dev->dev,
				"Bad status (%02x) at end of transaction\n",
				temp);
		}
		dev_dbg(&I801_dev->dev, "Block (post %d): CNT=%02x, CMD=%02x, "
			"ADD=%02x, DAT0=%02x, BLKDAT=%02x\n", i,
			inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
			inb_p(SMBHSTDAT0), inb_p(SMBBLKDAT));

		if (result < 0)
			goto END;
	}

#ifdef HAVE_PEC
	if(isich4 && command == I2C_SMBUS_BLOCK_DATA_PEC) {
		/* wait for INTR bit as advised by Intel */
		timeout = 0;
		do {
			temp = inb_p(SMBHSTSTS);
			msleep(1);
		} while ((!(temp & 0x02))
			   && (timeout++ < MAX_TIMEOUT));

		if (timeout >= MAX_TIMEOUT) {
			dev_dbg(&I801_dev->dev, "PEC Timeout!\n");
		}
		outb_p(temp, SMBHSTSTS); 
	}
#endif
	result = 0;
END:
	if (command == I2C_SMBUS_I2C_BLOCK_DATA) {
		/* restore saved configuration register value */
		pci_write_config_byte(I801_dev, SMBHSTCFG, hostc);
	}
	return result;
}

/* Return -1 on error. */
static s32 i801_access(struct i2c_adapter * adap, u16 addr,
		       unsigned short flags, char read_write, u8 command,
		       int size, union i2c_smbus_data * data)
{
	int hwpec = 0;
	int block = 0;
	int ret, xact = 0;

#ifdef HAVE_PEC
	if(isich4)
		hwpec = (flags & I2C_CLIENT_PEC) != 0;
#endif

	switch (size) {
	case I2C_SMBUS_QUICK:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		xact = I801_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);
		xact = I801_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);
		xact = I801_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);
		}
		xact = I801_WORD_DATA;
		break;
	case I2C_SMBUS_BLOCK_DATA:
	case I2C_SMBUS_I2C_BLOCK_DATA:
#ifdef HAVE_PEC
	case I2C_SMBUS_BLOCK_DATA_PEC:
		if(hwpec && size == I2C_SMBUS_BLOCK_DATA)
			size = I2C_SMBUS_BLOCK_DATA_PEC;
#endif
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		outb_p(command, SMBHSTCMD);
		block = 1;
		break;
	case I2C_SMBUS_PROC_CALL:
	default:
		dev_err(&I801_dev->dev, "Unsupported transaction %d\n", size);
		return -1;
	}

#ifdef HAVE_PEC
	if(isich4 && hwpec) {
		if(size != I2C_SMBUS_QUICK &&
		   size != I2C_SMBUS_I2C_BLOCK_DATA)
			outb_p(1, SMBAUXCTL);	/* enable HW PEC */
	}
#endif
	if(block)
		ret = i801_block_transaction(data, read_write, size);
	else {
		outb_p(xact | ENABLE_INT9, SMBHSTCNT);
		ret = i801_transaction();
	}

#ifdef HAVE_PEC
	if(isich4 && hwpec) {
		if(size != I2C_SMBUS_QUICK &&
		   size != I2C_SMBUS_I2C_BLOCK_DATA)
			outb_p(0, SMBAUXCTL);
	}
#endif

	if(block)
		return ret;
	if(ret)
		return -1;
	if ((read_write == I2C_SMBUS_WRITE) || (xact == I801_QUICK))
		return 0;

	switch (xact & 0x7f) {
	case I801_BYTE:	/* Result put in SMBHSTDAT0 */
	case I801_BYTE_DATA:
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case I801_WORD_DATA:
		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
		break;
	}
	return 0;
}


static u32 i801_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 | I2C_FUNC_SMBUS_WRITE_I2C_BLOCK
#ifdef HAVE_PEC
	     | (isich4 ? I2C_FUNC_SMBUS_BLOCK_DATA_PEC |
	                 I2C_FUNC_SMBUS_HWPEC_CALC
	               : 0)
#endif
	    ;
}

static struct i2c_algorithm smbus_algorithm = {
	.name		= "Non-I2C SMBus adapter",
	.id		= I2C_ALGO_SMBUS,
	.smbus_xfer	= i801_access,
	.functionality	= i801_func,
};

static struct i2c_adapter i801_adapter = {
	.owner		= THIS_MODULE,
	.class		= I2C_CLASS_HWMON,
	.algo		= &smbus_algorithm,
	.name		= "unset",
};

static struct pci_device_id i801_ids[] = {
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_82801AA_3,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_82801AB_3,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_82801BA_2,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_82801CA_3,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_82801DB_3,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_82801EB_3,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_ESB_4,
		.subvendor =	PCI_ANY_ID,
		.subdevice = 	PCI_ANY_ID,
	},
	{
		.vendor =	PCI_VENDOR_ID_INTEL,
		.device =	PCI_DEVICE_ID_INTEL_ICH6_16,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{ 0, }
};

static int __devinit i801_probe(struct pci_dev *dev, const struct pci_device_id *id)
{

	if (i801_setup(dev)) {
		dev_warn(&dev->dev,
			"I801 not detected, module not inserted.\n");
		return -ENODEV;
	}

	/* set up the driverfs linkage to our parent device */
	i801_adapter.dev.parent = &dev->dev;

	snprintf(i801_adapter.name, I2C_NAME_SIZE,
		"SMBus I801 adapter at %04x", i801_smba);
	return i2c_add_adapter(&i801_adapter);
}

static void __devexit i801_remove(struct pci_dev *dev)
{
	i2c_del_adapter(&i801_adapter);
	release_region(i801_smba, (isich4 ? 16 : 8));
}

static struct pci_driver i801_driver = {
	.name		= "i801 smbus",
	.id_table	= i801_ids,
	.probe		= i801_probe,
	.remove		= __devexit_p(i801_remove),
};

static int __init i2c_i801_init(void)
{
	return pci_module_init(&i801_driver);
}

static void __exit i2c_i801_exit(void)
{
	pci_unregister_driver(&i801_driver);
}

MODULE_AUTHOR ("Frodo Looijaard <[e-mail]>, "
		"Philip Edelbrock <[e-mail]>, "
		"and Mark D. Studebaker <[e-mail]>");
MODULE_DESCRIPTION("I801 SMBus driver");
MODULE_LICENSE("GPL");

module_init(i2c_i801_init);
module_exit(i2c_i801_exit);