i2c-ali15x3.c

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		outb_p(ALI15X3_T_OUT, SMBHSTCNT);
		temp = inb_p(SMBHSTSTS);
	}

	/* now check the error bits and the busy bit */
	if (temp & (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
		/* do a clear-on-write */
		outb_p(0xFF, SMBHSTSTS);
		if ((temp = inb_p(SMBHSTSTS)) &
		    (ALI15X3_STS_ERR | ALI15X3_STS_BUSY)) {
			/* this is probably going to be correctable only by a power reset
			   as one of the bits now appears to be stuck */
			/* This may be a bus or device with electrical problems. */
			dev_err(&adap->dev, "SMBus reset failed! (0x%02x) - "
				"controller or device on bus is probably hung\n",
				temp);
			return -1;
		}
	} else {
		/* check and clear done bit */
		if (temp & ALI15X3_STS_DONE) {
			outb_p(temp, SMBHSTSTS);
		}
	}

	/* start the transaction by writing anything to the start register */
	outb_p(0xFF, SMBHSTSTART);

	/* We will always wait for a fraction of a second! */
	timeout = 0;
	do {
		msleep(1);
		temp = inb_p(SMBHSTSTS);
	} while ((!(temp & (ALI15X3_STS_ERR | ALI15X3_STS_DONE)))
		 && (timeout++ < MAX_TIMEOUT));

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

	if (temp & ALI15X3_STS_TERM) {
		result = -1;
		dev_dbg(&adap->dev, "Error: Failed bus transaction\n");
	}

	/*
	  Unfortunately the ALI SMB controller maps "no response" and "bus
	  collision" into a single bit. No reponse is the usual case so don't
	  do a printk.
	  This means that bus collisions go unreported.
	*/
	if (temp & ALI15X3_STS_COLL) {
		result = -1;
		dev_dbg(&adap->dev,
			"Error: no response or bus collision ADD=%02x\n",
			inb_p(SMBHSTADD));
	}

	/* haven't ever seen this */
	if (temp & ALI15X3_STS_DEV) {
		result = -1;
		dev_err(&adap->dev, "Error: device error\n");
	}
	dev_dbg(&adap->dev, "Transaction (post): STS=%02x, CNT=%02x, CMD=%02x, "
		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb_p(SMBHSTSTS),
		inb_p(SMBHSTCNT), inb_p(SMBHSTCMD), inb_p(SMBHSTADD),
		inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));
	return result;
}

/* Return -1 on error. */
static s32 ali15x3_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 temp;
	int timeout;

	/* clear all the bits (clear-on-write) */
	outb_p(0xFF, SMBHSTSTS);
	/* make sure SMBus is idle */
	temp = inb_p(SMBHSTSTS);
	for (timeout = 0;
	     (timeout < MAX_TIMEOUT) && !(temp & ALI15X3_STS_IDLE);
	     timeout++) {
		msleep(1);
		temp = inb_p(SMBHSTSTS);
	}
	if (timeout >= MAX_TIMEOUT) {
		dev_err(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);
	}

	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 = ALI15X3_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 = ALI15X3_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 = ALI15X3_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 = ALI15X3_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;
				data->block[0] = len;
			}
			if (len > 32) {
				len = 32;
				data->block[0] = len;
			}
			outb_p(len, SMBHSTDAT0);
			/* Reset SMBBLKDAT */
			outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
			for (i = 1; i <= len; i++)
				outb_p(data->block[i], SMBBLKDAT);
		}
		size = ALI15X3_BLOCK_DATA;
		break;
	}

	outb_p(size, SMBHSTCNT);	/* output command */

	if (ali15x3_transaction(adap))	/* Error in transaction */
		return -1;

	if ((read_write == I2C_SMBUS_WRITE) || (size == ALI15X3_QUICK))
		return 0;


	switch (size) {
	case ALI15X3_BYTE:	/* Result put in SMBHSTDAT0 */
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case ALI15X3_BYTE_DATA:
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case ALI15X3_WORD_DATA:
		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
		break;
	case ALI15X3_BLOCK_DATA:
		len = inb_p(SMBHSTDAT0);
		if (len > 32)
			len = 32;
		data->block[0] = len;
		/* Reset SMBBLKDAT */
		outb_p(inb_p(SMBHSTCNT) | ALI15X3_BLOCK_CLR, SMBHSTCNT);
		for (i = 1; i <= data->block[0]; i++) {
			data->block[i] = inb_p(SMBBLKDAT);
			dev_dbg(&adap->dev, "Blk: len=%d, i=%d, data=%02x\n",
				len, i, data->block[i]);
		}
		break;
	}
	return 0;
}

static u32 ali15x3_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 = {
	.name		= "Non-I2C SMBus adapter",
	.id		= I2C_ALGO_SMBUS,
	.smbus_xfer	= ali15x3_access,
	.functionality	= ali15x3_func,
};

static struct i2c_adapter ali15x3_adapter = {
	.owner		= THIS_MODULE,
	.class          = I2C_CLASS_HWMON,
	.algo		= &smbus_algorithm,
	.name		= "unset",
};

static struct pci_device_id ali15x3_ids[] = {
	{
	.vendor =	PCI_VENDOR_ID_AL,
	.device =	PCI_DEVICE_ID_AL_M7101,
	.subvendor =	PCI_ANY_ID,
	.subdevice =	PCI_ANY_ID,
	},
	{ 0, }
};

static int __devinit ali15x3_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	if (ali15x3_setup(dev)) {
		dev_err(&dev->dev,
			"ALI15X3 not detected, module not inserted.\n");
		return -ENODEV;
	}

	/* set up the driverfs linkage to our parent device */
	ali15x3_adapter.dev.parent = &dev->dev;

	snprintf(ali15x3_adapter.name, I2C_NAME_SIZE,
		"SMBus ALI15X3 adapter at %04x", ali15x3_smba);
	return i2c_add_adapter(&ali15x3_adapter);
}

static void __devexit ali15x3_remove(struct pci_dev *dev)
{
	i2c_del_adapter(&ali15x3_adapter);
	release_region(ali15x3_smba, ALI15X3_SMB_IOSIZE);
}

static struct pci_driver ali15x3_driver = {
	.name		= "ali15x3 smbus",
	.id_table	= ali15x3_ids,
	.probe		= ali15x3_probe,
	.remove		= __devexit_p(ali15x3_remove),
};

static int __init i2c_ali15x3_init(void)
{
	return pci_module_init(&ali15x3_driver);
}

static void __exit i2c_ali15x3_exit(void)
{
	pci_unregister_driver(&ali15x3_driver);
}

MODULE_AUTHOR ("Frodo Looijaard <[e-mail]>, "
		"Philip Edelbrock <[e-mail]>, "
		"and Mark D. Studebaker <[e-mail]>");
MODULE_DESCRIPTION("ALI15X3 SMBus driver");
MODULE_LICENSE("GPL");

module_init(i2c_ali15x3_init);
module_exit(i2c_ali15x3_exit);