i2c-ali1535.c

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	outb_p(0xFF, SMBHSTPORT);

	/* We will always wait for a fraction of a second! */
	timeout = 0;
	do {
		msleep(1);
		temp = inb_p(SMBHSTSTS);
	} while (((temp & ALI1535_STS_BUSY) && !(temp & ALI1535_STS_IDLE))
		 && (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 & ALI1535_STS_FAIL) {
		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 & ALI1535_STS_BUSERR) {
		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 & ALI1535_STS_DEV) {
		result = -1;
		dev_err(&adap->dev, "Error: device error\n");
	}

	/* check to see if the "command complete" indication is set */
	if (!(temp & ALI1535_STS_DONE)) {
		result = -1;
		dev_err(&adap->dev, "Error: command never completed\n");
	}

	dev_dbg(&adap->dev, "Transaction (post): STS=%02x, TYP=%02x, "
		"CMD=%02x, ADD=%02x, DAT0=%02x, DAT1=%02x\n",
		inb_p(SMBHSTSTS), inb_p(SMBHSTTYP), inb_p(SMBHSTCMD),
		inb_p(SMBHSTADD), inb_p(SMBHSTDAT0), inb_p(SMBHSTDAT1));

	/* take consequent actions for error conditions */
	if (!(temp & ALI1535_STS_DONE)) {
		/* issue "kill" to reset host controller */
		outb_p(ALI1535_KILL,SMBHSTTYP);
		outb_p(0xFF,SMBHSTSTS);
	} else if (temp & ALI1535_STS_ERR) {
		/* issue "timeout" to reset all devices on bus */
		outb_p(ALI1535_T_OUT,SMBHSTTYP);
		outb_p(0xFF,SMBHSTSTS);
	}

	return result;
}

/* Return -1 on error. */
static s32 ali1535_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;
	s32 result = 0;

	down(&i2c_ali1535_sem);
	/* make sure SMBus is idle */
	temp = inb_p(SMBHSTSTS);
	for (timeout = 0;
	     (timeout < MAX_TIMEOUT) && !(temp & ALI1535_STS_IDLE);
	     timeout++) {
		msleep(1);
		temp = inb_p(SMBHSTSTS);
	}
	if (timeout >= MAX_TIMEOUT)
		dev_warn(&adap->dev, "Idle wait Timeout! STS=0x%02x\n", temp);

	/* clear status register (clear-on-write) */
	outb_p(0xFF, SMBHSTSTS);

	switch (size) {
	case I2C_SMBUS_PROC_CALL:
		dev_err(&adap->dev, "I2C_SMBUS_PROC_CALL not supported!\n");
		result = -1;
		goto EXIT;
	case I2C_SMBUS_QUICK:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_QUICK;
		outb_p(size, SMBHSTTYP);	/* output command */
		break;
	case I2C_SMBUS_BYTE:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_BYTE;
		outb_p(size, SMBHSTTYP);	/* output command */
		if (read_write == I2C_SMBUS_WRITE)
			outb_p(command, SMBHSTCMD);
		break;
	case I2C_SMBUS_BYTE_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_BYTE_DATA;
		outb_p(size, SMBHSTTYP);	/* output command */
		outb_p(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE)
			outb_p(data->byte, SMBHSTDAT0);
		break;
	case I2C_SMBUS_WORD_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_WORD_DATA;
		outb_p(size, SMBHSTTYP);	/* output command */
		outb_p(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE) {
			outb_p(data->word & 0xff, SMBHSTDAT0);
			outb_p((data->word & 0xff00) >> 8, SMBHSTDAT1);
		}
		break;
	case I2C_SMBUS_BLOCK_DATA:
		outb_p(((addr & 0x7f) << 1) | (read_write & 0x01),
		       SMBHSTADD);
		size = ALI1535_BLOCK_DATA;
		outb_p(size, SMBHSTTYP);	/* output command */
		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(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP);
			for (i = 1; i <= len; i++)
				outb_p(data->block[i], SMBBLKDAT);
		}
		break;
	}

	if (ali1535_transaction(adap)) {
		/* Error in transaction */
		result = -1;
		goto EXIT;
	}

	if ((read_write == I2C_SMBUS_WRITE) || (size == ALI1535_QUICK)) {
		result = 0;
		goto EXIT;
	}

	switch (size) {
	case ALI1535_BYTE:	/* Result put in SMBHSTDAT0 */
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case ALI1535_BYTE_DATA:
		data->byte = inb_p(SMBHSTDAT0);
		break;
	case ALI1535_WORD_DATA:
		data->word = inb_p(SMBHSTDAT0) + (inb_p(SMBHSTDAT1) << 8);
		break;
	case ALI1535_BLOCK_DATA:
		len = inb_p(SMBHSTDAT0);
		if (len > 32)
			len = 32;
		data->block[0] = len;
		/* Reset SMBBLKDAT */
		outb_p(inb_p(SMBHSTTYP) | ALI1535_BLOCK_CLR, SMBHSTTYP);
		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;
	}
EXIT:
	up(&i2c_ali1535_sem);
	return result;
}


u32 ali1535_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	= ali1535_access,
	.functionality	= ali1535_func,
};

static struct i2c_adapter ali1535_adapter = {
	.owner		= THIS_MODULE,
	.class          = I2C_CLASS_HWMON,
	.algo		= &smbus_algorithm,
	.name		= "unset",
};

static struct pci_device_id ali1535_ids[] = {
	{
		.vendor =	PCI_VENDOR_ID_AL,
		.device =	PCI_DEVICE_ID_AL_M7101,
		.subvendor =	PCI_ANY_ID,
		.subdevice =	PCI_ANY_ID,
	},
	{ },
};

static int __devinit ali1535_probe(struct pci_dev *dev, const struct pci_device_id *id)
{
	if (ali1535_setup(dev)) {
		dev_warn(&dev->dev,
			"ALI1535 not detected, module not inserted.\n");
		return -ENODEV;
	}

	/* set up the driverfs linkage to our parent device */
	ali1535_adapter.dev.parent = &dev->dev;

	snprintf(ali1535_adapter.name, I2C_NAME_SIZE, 
		"SMBus ALI1535 adapter at %04x", ali1535_smba);
	return i2c_add_adapter(&ali1535_adapter);
}

static void __devexit ali1535_remove(struct pci_dev *dev)
{
	i2c_del_adapter(&ali1535_adapter);
	release_region(ali1535_smba, ALI1535_SMB_IOSIZE);
}

static struct pci_driver ali1535_driver = {
	.name		= "ali1535_smbus",
	.id_table	= ali1535_ids,
	.probe		= ali1535_probe,
	.remove		= __devexit_p(ali1535_remove),
};

static int __init i2c_ali1535_init(void)
{
	return pci_module_init(&ali1535_driver);
}

static void __exit i2c_ali1535_exit(void)
{
	pci_unregister_driver(&ali1535_driver);
}

MODULE_AUTHOR("Frodo Looijaard <[e-mail]>, "
	      "Philip Edelbrock <[e-mail]>, "
	      "Mark D. Studebaker <[e-mail]> "
	      "and Dan Eaton <[e-mail]>");
MODULE_DESCRIPTION("ALI1535 SMBus driver");
MODULE_LICENSE("GPL");

module_init(i2c_ali1535_init);
module_exit(i2c_ali1535_exit);