[mirror_ubuntu-bionic-kernel.git] / drivers / i2c / busses / i2c-isch.c

/*
    i2c-isch.c - Linux kernel driver for Intel SCH chipset SMBus
    - Based on i2c-piix4.c
    Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and
    Philip Edelbrock <phil@netroedge.com>
    - Intel SCH support
    Copyright (c) 2007 - 2008 Jacob Jun Pan <jacob.jun.pan@intel.com>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License version 2 as
    published by the Free Software Foundation.

    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 SCH chipsets (AF82US15W, AF82US15L, AF82UL11L)
   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/init.h>
#include <linux/io.h>
#include <linux/acpi.h>

/* SCH SMBus address offsets */
#define SMBHSTCNT	(0 + sch_smba)
#define SMBHSTSTS	(1 + sch_smba)
#define SMBHSTADD	(4 + sch_smba) /* TSA */
#define SMBHSTCMD	(5 + sch_smba)
#define SMBHSTDAT0	(6 + sch_smba)
#define SMBHSTDAT1	(7 + sch_smba)
#define SMBBLKDAT	(0x20 + sch_smba)

/* count for request_region */
#define SMBIOSIZE	64

/* PCI Address Constants */
#define SMBBA_SCH	0x40

/* Other settings */
#define MAX_TIMEOUT	500

/* I2C constants */
#define SCH_QUICK		0x00
#define SCH_BYTE		0x01
#define SCH_BYTE_DATA		0x02
#define SCH_WORD_DATA		0x03
#define SCH_BLOCK_DATA		0x05

static unsigned short sch_smba;
static struct pci_driver sch_driver;
static struct i2c_adapter sch_adapter;

/*
 * Start the i2c transaction -- the i2c_access will prepare the transaction
 * and this function will execute it.
 * return 0 for success and others for failure.
 */
static int sch_transaction(void)
{
	int temp;
	int result = 0;
	int timeout = 0;

	dev_dbg(&sch_adapter.dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT),
		inb(SMBHSTCMD), inb(SMBHSTADD), inb(SMBHSTDAT0),
		inb(SMBHSTDAT1));

	/* Make sure the SMBus host is ready to start transmitting */
	temp = inb(SMBHSTSTS) & 0x0f;
	if (temp) {
		/* Can not be busy since we checked it in sch_access */
		if (temp & 0x01) {
			dev_dbg(&sch_adapter.dev, "Completion (%02x). "
				"Clear...\n", temp);
		}
		if (temp & 0x06) {
			dev_dbg(&sch_adapter.dev, "SMBus error (%02x). "
				"Resetting...\n", temp);
		}
		outb(temp, SMBHSTSTS);
		temp = inb(SMBHSTSTS) & 0x0f;
		if (temp) {
			dev_err(&sch_adapter.dev,
				"SMBus is not ready: (%02x)\n", temp);
			return -EAGAIN;
		}
	}

	/* start the transaction by setting bit 4 */
	outb(inb(SMBHSTCNT) | 0x10, SMBHSTCNT);

	do {
		msleep(1);
		temp = inb(SMBHSTSTS) & 0x0f;
	} while ((temp & 0x08) && (timeout++ < MAX_TIMEOUT));

	/* If the SMBus is still busy, we give up */
	if (timeout > MAX_TIMEOUT) {
		dev_err(&sch_adapter.dev, "SMBus Timeout!\n");
		result = -ETIMEDOUT;
	}
	if (temp & 0x04) {
		result = -EIO;
		dev_dbg(&sch_adapter.dev, "Bus collision! SMBus may be "
			"locked until next hard reset. (sorry!)\n");
		/* Clock stops and slave is stuck in mid-transmission */
	} else if (temp & 0x02) {
		result = -EIO;
		dev_err(&sch_adapter.dev, "Error: no response!\n");
	} else if (temp & 0x01) {
		dev_dbg(&sch_adapter.dev, "Post complete!\n");
		outb(temp, SMBHSTSTS);
		temp = inb(SMBHSTSTS) & 0x07;
		if (temp & 0x06) {
			/* Completion clear failed */
			dev_dbg(&sch_adapter.dev, "Failed reset at end of "
				"transaction (%02x), Bus error!\n", temp);
		}
	} else {
		result = -ENXIO;
		dev_dbg(&sch_adapter.dev, "No such address.\n");
	}
	dev_dbg(&sch_adapter.dev, "Transaction (post): CNT=%02x, CMD=%02x, "
		"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT),
		inb(SMBHSTCMD), inb(SMBHSTADD), inb(SMBHSTDAT0),
		inb(SMBHSTDAT1));
	return result;
}

/*
 * This is the main access entry for i2c-sch access
 * adap is i2c_adapter pointer, addr is the i2c device bus address, read_write
 * (0 for read and 1 for write), size is i2c transaction type and data is the
 * union of transaction for data to be transfered or data read from bus.
 * return 0 for success and others for failure.
 */
static s32 sch_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, temp, rc;

	/* Make sure the SMBus host is not busy */
	temp = inb(SMBHSTSTS) & 0x0f;
	if (temp & 0x08) {
		dev_dbg(&sch_adapter.dev, "SMBus busy (%02x)\n", temp);
		return -EAGAIN;
	}
	dev_dbg(&sch_adapter.dev, "access size: %d %s\n", size,
		(read_write)?"READ":"WRITE");
	switch (size) {
	case I2C_SMBUS_QUICK:
		outb((addr << 1) | read_write, SMBHSTADD);
		size = SCH_QUICK;
		break;
	case I2C_SMBUS_BYTE:
		outb((addr << 1) | read_write, SMBHSTADD);
		if (read_write == I2C_SMBUS_WRITE)
			outb(command, SMBHSTCMD);
		size = SCH_BYTE;
		break;
	case I2C_SMBUS_BYTE_DATA:
		outb((addr << 1) | read_write, SMBHSTADD);
		outb(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE)
			outb(data->byte, SMBHSTDAT0);
		size = SCH_BYTE_DATA;
		break;
	case I2C_SMBUS_WORD_DATA:
		outb((addr << 1) | read_write, SMBHSTADD);
		outb(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE) {
			outb(data->word & 0xff, SMBHSTDAT0);
			outb((data->word & 0xff00) >> 8, SMBHSTDAT1);
		}
		size = SCH_WORD_DATA;
		break;
	case I2C_SMBUS_BLOCK_DATA:
		outb((addr << 1) | read_write, SMBHSTADD);
		outb(command, SMBHSTCMD);
		if (read_write == I2C_SMBUS_WRITE) {
			len = data->block[0];
			if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
				return -EINVAL;
			outb(len, SMBHSTDAT0);
			for (i = 1; i <= len; i++)
				outb(data->block[i], SMBBLKDAT+i-1);
		}
		size = SCH_BLOCK_DATA;
		break;
	default:
		dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
		return -EOPNOTSUPP;
	}
	dev_dbg(&sch_adapter.dev, "write size %d to 0x%04x\n", size, SMBHSTCNT);
	outb((inb(SMBHSTCNT) & 0xb0) | (size & 0x7), SMBHSTCNT);

	rc = sch_transaction();
	if (rc)	/* Error in transaction */
		return rc;

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

	switch (size) {
	case SCH_BYTE:
	case SCH_BYTE_DATA:
		data->byte = inb(SMBHSTDAT0);
		break;
	case SCH_WORD_DATA:
		data->word = inb(SMBHSTDAT0) + (inb(SMBHSTDAT1) << 8);
		break;
	case SCH_BLOCK_DATA:
		data->block[0] = inb(SMBHSTDAT0);
		if (data->block[0] == 0 || data->block[0] > I2C_SMBUS_BLOCK_MAX)
			return -EPROTO;
		for (i = 1; i <= data->block[0]; i++)
			data->block[i] = inb(SMBBLKDAT+i-1);
		break;
	}
	return 0;
}

static u32 sch_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	= sch_access,
	.functionality	= sch_func,
};

static struct i2c_adapter sch_adapter = {
	.owner		= THIS_MODULE,
	.class		= I2C_CLASS_HWMON | I2C_CLASS_SPD,
	.algo		= &smbus_algorithm,
};

static struct pci_device_id sch_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC) },
	{ 0, }
};

MODULE_DEVICE_TABLE(pci, sch_ids);

static int __devinit sch_probe(struct pci_dev *dev,
				const struct pci_device_id *id)
{
	int retval;
	unsigned int smba;

	pci_read_config_dword(dev, SMBBA_SCH, &smba);
	if (!(smba & (1 << 31))) {
		dev_err(&dev->dev, "SMBus I/O space disabled!\n");
		return -ENODEV;
	}

	sch_smba = (unsigned short)smba;
	if (sch_smba == 0) {
		dev_err(&dev->dev, "SMBus base address uninitialized!\n");
		return -ENODEV;
	}
	if (acpi_check_region(sch_smba, SMBIOSIZE, sch_driver.name))
		return -EBUSY;
	if (!request_region(sch_smba, SMBIOSIZE, sch_driver.name)) {
		dev_err(&dev->dev, "SMBus region 0x%x already in use!\n",
			sch_smba);
		return -EBUSY;
	}
	dev_dbg(&dev->dev, "SMBA = 0x%X\n", sch_smba);

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

	snprintf(sch_adapter.name, sizeof(sch_adapter.name),
		"SMBus SCH adapter at %04x", sch_smba);

	retval = i2c_add_adapter(&sch_adapter);
	if (retval) {
		dev_err(&dev->dev, "Couldn't register adapter!\n");
		release_region(sch_smba, SMBIOSIZE);
		sch_smba = 0;
	}

	return retval;
}

static void __devexit sch_remove(struct pci_dev *dev)
{
	if (sch_smba) {
		i2c_del_adapter(&sch_adapter);
		release_region(sch_smba, SMBIOSIZE);
		sch_smba = 0;
	}
}

static struct pci_driver sch_driver = {
	.name		= "isch_smbus",
	.id_table	= sch_ids,
	.probe		= sch_probe,
	.remove		= __devexit_p(sch_remove),
};

static int __init i2c_sch_init(void)
{
	return pci_register_driver(&sch_driver);
}

static void __exit i2c_sch_exit(void)
{
	pci_unregister_driver(&sch_driver);
}

MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@intel.com>");
MODULE_DESCRIPTION("Intel SCH SMBus driver");
MODULE_LICENSE("GPL");

module_init(i2c_sch_init);
module_exit(i2c_sch_exit);
Commit	Line	Data
5bc12008 AD	1	/*
	2	i2c-isch.c - Linux kernel driver for Intel SCH chipset SMBus
	3	- Based on i2c-piix4.c
	4	Copyright (c) 1998 - 2002 Frodo Looijaard <frodol@dds.nl> and
	5	Philip Edelbrock <phil@netroedge.com>
	6	- Intel SCH support
	7	Copyright (c) 2007 - 2008 Jacob Jun Pan <jacob.jun.pan@intel.com>
	8
	9	This program is free software; you can redistribute it and/or modify
	10	it under the terms of the GNU General Public License version 2 as
	11	published by the Free Software Foundation.
	12
	13	This program is distributed in the hope that it will be useful,
	14	but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	GNU General Public License for more details.
	17
	18	You should have received a copy of the GNU General Public License
	19	along with this program; if not, write to the Free Software
	20	Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	21	*/
	22
	23	/*
	24	Supports:
	25	Intel SCH chipsets (AF82US15W, AF82US15L, AF82UL11L)
	26	Note: we assume there can only be one device, with one SMBus interface.
	27	*/
	28
	29	#include <linux/module.h>
	30	#include <linux/pci.h>
	31	#include <linux/kernel.h>
	32	#include <linux/delay.h>
	33	#include <linux/stddef.h>
	34	#include <linux/ioport.h>
	35	#include <linux/i2c.h>
	36	#include <linux/init.h>
	37	#include <linux/io.h>
54fb4a05	38	#include <linux/acpi.h>
5bc12008 AD	39
	40	/* SCH SMBus address offsets */
	41	#define SMBHSTCNT (0 + sch_smba)
	42	#define SMBHSTSTS (1 + sch_smba)
	43	#define SMBHSTADD (4 + sch_smba) /* TSA */
	44	#define SMBHSTCMD (5 + sch_smba)
	45	#define SMBHSTDAT0 (6 + sch_smba)
	46	#define SMBHSTDAT1 (7 + sch_smba)
	47	#define SMBBLKDAT (0x20 + sch_smba)
	48
	49	/* count for request_region */
	50	#define SMBIOSIZE 64
	51
	52	/* PCI Address Constants */
	53	#define SMBBA_SCH 0x40
	54
	55	/* Other settings */
	56	#define MAX_TIMEOUT 500
	57
	58	/* I2C constants */
	59	#define SCH_QUICK 0x00
	60	#define SCH_BYTE 0x01
	61	#define SCH_BYTE_DATA 0x02
	62	#define SCH_WORD_DATA 0x03
	63	#define SCH_BLOCK_DATA 0x05
	64
	65	static unsigned short sch_smba;
	66	static struct pci_driver sch_driver;
	67	static struct i2c_adapter sch_adapter;
	68
	69	/*
	70	* Start the i2c transaction -- the i2c_access will prepare the transaction
	71	* and this function will execute it.
	72	* return 0 for success and others for failure.
	73	*/
	74	static int sch_transaction(void)
	75	{
	76	int temp;
	77	int result = 0;
	78	int timeout = 0;
	79
	80	dev_dbg(&sch_adapter.dev, "Transaction (pre): CNT=%02x, CMD=%02x, "
	81	"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT),
	82	inb(SMBHSTCMD), inb(SMBHSTADD), inb(SMBHSTDAT0),
	83	inb(SMBHSTDAT1));
	84
	85	/* Make sure the SMBus host is ready to start transmitting */
	86	temp = inb(SMBHSTSTS) & 0x0f;
	87	if (temp) {
	88	/* Can not be busy since we checked it in sch_access */
	89	if (temp & 0x01) {
	90	dev_dbg(&sch_adapter.dev, "Completion (%02x). "
	91	"Clear...\n", temp);
	92	}
	93	if (temp & 0x06) {
	94	dev_dbg(&sch_adapter.dev, "SMBus error (%02x). "
	95	"Resetting...\n", temp);
	96	}
	97	outb(temp, SMBHSTSTS);
	98	temp = inb(SMBHSTSTS) & 0x0f;
	99	if (temp) {
	100	dev_err(&sch_adapter.dev,
	101	"SMBus is not ready: (%02x)\n", temp);
	102	return -EAGAIN;
103	}
104	}
105
106	/* start the transaction by setting bit 4 */
107	outb(inb(SMBHSTCNT) \| 0x10, SMBHSTCNT);
108
109	do {
110	msleep(1);
111	temp = inb(SMBHSTSTS) & 0x0f;
112	} while ((temp & 0x08) && (timeout++ < MAX_TIMEOUT));
113
114	/* If the SMBus is still busy, we give up */
4ccc28f7	115	if (timeout > MAX_TIMEOUT) {
5bc12008 AD	116	dev_err(&sch_adapter.dev, "SMBus Timeout!\n");
	117	result = -ETIMEDOUT;
	118	}
	119	if (temp & 0x04) {
	120	result = -EIO;
	121	dev_dbg(&sch_adapter.dev, "Bus collision! SMBus may be "
	122	"locked until next hard reset. (sorry!)\n");
	123	/* Clock stops and slave is stuck in mid-transmission */
	124	} else if (temp & 0x02) {
	125	result = -EIO;
	126	dev_err(&sch_adapter.dev, "Error: no response!\n");
	127	} else if (temp & 0x01) {
	128	dev_dbg(&sch_adapter.dev, "Post complete!\n");
	129	outb(temp, SMBHSTSTS);
	130	temp = inb(SMBHSTSTS) & 0x07;
	131	if (temp & 0x06) {
	132	/* Completion clear failed */
	133	dev_dbg(&sch_adapter.dev, "Failed reset at end of "
	134	"transaction (%02x), Bus error!\n", temp);
	135	}
	136	} else {
	137	result = -ENXIO;
	138	dev_dbg(&sch_adapter.dev, "No such address.\n");
	139	}
	140	dev_dbg(&sch_adapter.dev, "Transaction (post): CNT=%02x, CMD=%02x, "
	141	"ADD=%02x, DAT0=%02x, DAT1=%02x\n", inb(SMBHSTCNT),
	142	inb(SMBHSTCMD), inb(SMBHSTADD), inb(SMBHSTDAT0),
	143	inb(SMBHSTDAT1));
	144	return result;
	145	}
	146
	147	/*
	148	* This is the main access entry for i2c-sch access
	149	* adap is i2c_adapter pointer, addr is the i2c device bus address, read_write
	150	* (0 for read and 1 for write), size is i2c transaction type and data is the
	151	* union of transaction for data to be transfered or data read from bus.
	152	* return 0 for success and others for failure.
	153	*/
	154	static s32 sch_access(struct i2c_adapter *adap, u16 addr,
	155	unsigned short flags, char read_write,
	156	u8 command, int size, union i2c_smbus_data *data)
	157	{
	158	int i, len, temp, rc;
	159
	160	/* Make sure the SMBus host is not busy */
	161	temp = inb(SMBHSTSTS) & 0x0f;
	162	if (temp & 0x08) {
	163	dev_dbg(&sch_adapter.dev, "SMBus busy (%02x)\n", temp);
	164	return -EAGAIN;
	165	}
	166	dev_dbg(&sch_adapter.dev, "access size: %d %s\n", size,
	167	(read_write)?"READ":"WRITE");
	168	switch (size) {
	169	case I2C_SMBUS_QUICK:
	170	outb((addr << 1) \| read_write, SMBHSTADD);
	171	size = SCH_QUICK;
	172	break;
	173	case I2C_SMBUS_BYTE:
	174	outb((addr << 1) \| read_write, SMBHSTADD);
	175	if (read_write == I2C_SMBUS_WRITE)
	176	outb(command, SMBHSTCMD);
	177	size = SCH_BYTE;
	178	break;
	179	case I2C_SMBUS_BYTE_DATA:
180	outb((addr << 1) \| read_write, SMBHSTADD);
181	outb(command, SMBHSTCMD);
182	if (read_write == I2C_SMBUS_WRITE)
183	outb(data->byte, SMBHSTDAT0);
184	size = SCH_BYTE_DATA;
185	break;
186	case I2C_SMBUS_WORD_DATA:
187	outb((addr << 1) \| read_write, SMBHSTADD);
188	outb(command, SMBHSTCMD);
189	if (read_write == I2C_SMBUS_WRITE) {
190	outb(data->word & 0xff, SMBHSTDAT0);
191	outb((data->word & 0xff00) >> 8, SMBHSTDAT1);
192	}
193	size = SCH_WORD_DATA;
194	break;
195	case I2C_SMBUS_BLOCK_DATA:
196	outb((addr << 1) \| read_write, SMBHSTADD);
197	outb(command, SMBHSTCMD);
198	if (read_write == I2C_SMBUS_WRITE) {
199	len = data->block[0];
200	if (len == 0 \|\| len > I2C_SMBUS_BLOCK_MAX)
201	return -EINVAL;
202	outb(len, SMBHSTDAT0);
203	for (i = 1; i <= len; i++)
204	outb(data->block[i], SMBBLKDAT+i-1);
205	}
206	size = SCH_BLOCK_DATA;
207	break;
208	default:
209	dev_warn(&adap->dev, "Unsupported transaction %d\n", size);
210	return -EOPNOTSUPP;
211	}
212	dev_dbg(&sch_adapter.dev, "write size %d to 0x%04x\n", size, SMBHSTCNT);
213	outb((inb(SMBHSTCNT) & 0xb0) \| (size & 0x7), SMBHSTCNT);
214
215	rc = sch_transaction();
216	if (rc) /* Error in transaction */
217	return rc;
218
219	if ((read_write == I2C_SMBUS_WRITE) \|\| (size == SCH_QUICK))
220	return 0;
221
222	switch (size) {
223	case SCH_BYTE:
224	case SCH_BYTE_DATA:
225	data->byte = inb(SMBHSTDAT0);
226	break;
227	case SCH_WORD_DATA:
228	data->word = inb(SMBHSTDAT0) + (inb(SMBHSTDAT1) << 8);
229	break;
230	case SCH_BLOCK_DATA:
231	data->block[0] = inb(SMBHSTDAT0);
232	if (data->block[0] == 0 \|\| data->block[0] > I2C_SMBUS_BLOCK_MAX)
233	return -EPROTO;
234	for (i = 1; i <= data->block[0]; i++)
235	data->block[i] = inb(SMBBLKDAT+i-1);
236	break;
237	}
238	return 0;
239	}
240
241	static u32 sch_func(struct i2c_adapter *adapter)
242	{
243	return I2C_FUNC_SMBUS_QUICK \| I2C_FUNC_SMBUS_BYTE \|
244	I2C_FUNC_SMBUS_BYTE_DATA \| I2C_FUNC_SMBUS_WORD_DATA \|
245	I2C_FUNC_SMBUS_BLOCK_DATA;
246	}
247
248	static const struct i2c_algorithm smbus_algorithm = {
249	.smbus_xfer = sch_access,
250	.functionality = sch_func,
251	};
252
253	static struct i2c_adapter sch_adapter = {
254	.owner = THIS_MODULE,
3401b2ff	255	.class = I2C_CLASS_HWMON \| I2C_CLASS_SPD,
5bc12008 AD	256	.algo = &smbus_algorithm,
	257	};
	258
	259	static struct pci_device_id sch_ids[] = {
	260	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SCH_LPC) },
	261	{ 0, }
	262	};
	263
	264	MODULE_DEVICE_TABLE(pci, sch_ids);
	265
	266	static int __devinit sch_probe(struct pci_dev *dev,
	267	const struct pci_device_id *id)
	268	{
	269	int retval;
	270	unsigned int smba;
	271
	272	pci_read_config_dword(dev, SMBBA_SCH, &smba);
	273	if (!(smba & (1 << 31))) {
	274	dev_err(&dev->dev, "SMBus I/O space disabled!\n");
	275	return -ENODEV;
	276	}
	277
	278	sch_smba = (unsigned short)smba;
	279	if (sch_smba == 0) {
	280	dev_err(&dev->dev, "SMBus base address uninitialized!\n");
	281	return -ENODEV;
	282	}
54fb4a05 JD	283	if (acpi_check_region(sch_smba, SMBIOSIZE, sch_driver.name))
54fb4a05 JD	284	return -EBUSY;
5bc12008 AD	285	if (!request_region(sch_smba, SMBIOSIZE, sch_driver.name)) {
	286	dev_err(&dev->dev, "SMBus region 0x%x already in use!\n",
	287	sch_smba);
	288	return -EBUSY;
	289	}
	290	dev_dbg(&dev->dev, "SMBA = 0x%X\n", sch_smba);
	291
	292	/* set up the sysfs linkage to our parent device */
	293	sch_adapter.dev.parent = &dev->dev;
	294
	295	snprintf(sch_adapter.name, sizeof(sch_adapter.name),
	296	"SMBus SCH adapter at %04x", sch_smba);
	297
	298	retval = i2c_add_adapter(&sch_adapter);
	299	if (retval) {
	300	dev_err(&dev->dev, "Couldn't register adapter!\n");
	301	release_region(sch_smba, SMBIOSIZE);
	302	sch_smba = 0;
	303	}
	304
	305	return retval;
	306	}
	307
	308	static void __devexit sch_remove(struct pci_dev *dev)
	309	{
	310	if (sch_smba) {
	311	i2c_del_adapter(&sch_adapter);
	312	release_region(sch_smba, SMBIOSIZE);
	313	sch_smba = 0;
	314	}
	315	}
	316
	317	static struct pci_driver sch_driver = {
	318	.name = "isch_smbus",
	319	.id_table = sch_ids,
	320	.probe = sch_probe,
	321	.remove = __devexit_p(sch_remove),
	322	};
	323
	324	static int __init i2c_sch_init(void)
	325	{
	326	return pci_register_driver(&sch_driver);
	327	}
	328
	329	static void __exit i2c_sch_exit(void)
	330	{
	331	pci_unregister_driver(&sch_driver);
	332	}
	333
	334	MODULE_AUTHOR("Jacob Pan <jacob.jun.pan@intel.com>");
	335	MODULE_DESCRIPTION("Intel SCH SMBus driver");
	336	MODULE_LICENSE("GPL");
	337
	338	module_init(i2c_sch_init);
	339	module_exit(i2c_sch_exit);