[deliverable/linux.git] / drivers / i2c / busses / i2c-simtec.c

/*
 * Copyright (C) 2005 Simtec Electronics
 *	Ben Dooks <ben@simtec.co.uk>
 *
 * Simtec Generic I2C Controller
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License
 *
 * 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/io.h>

#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>

struct simtec_i2c_data {
	struct resource		*ioarea;
	void __iomem		*reg;
	struct i2c_adapter	 adap;
	struct i2c_algo_bit_data bit;
};

#define CMD_SET_SDA	(1<<2)
#define CMD_SET_SCL	(1<<3)

#define STATE_SDA	(1<<0)
#define STATE_SCL	(1<<1)

/* i2c bit-bus functions */

static void simtec_i2c_setsda(void *pw, int state)
{
	struct simtec_i2c_data *pd = pw;
	writeb(CMD_SET_SDA | (state ? STATE_SDA : 0), pd->reg);
}

static void simtec_i2c_setscl(void *pw, int state)
{
	struct simtec_i2c_data *pd = pw;
	writeb(CMD_SET_SCL | (state ? STATE_SCL : 0), pd->reg);
}

static int simtec_i2c_getsda(void *pw)
{
	struct simtec_i2c_data *pd = pw;
	return readb(pd->reg) & STATE_SDA ? 1 : 0;
}

static int simtec_i2c_getscl(void *pw)
{
	struct simtec_i2c_data *pd = pw;
	return readb(pd->reg) & STATE_SCL ? 1 : 0;
}

/* device registration */

static int simtec_i2c_probe(struct platform_device *dev)
{
	struct simtec_i2c_data *pd;
	struct resource *res;
	int size;
	int ret;

	pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL);
	if (pd == NULL)
		return -ENOMEM;

	platform_set_drvdata(dev, pd);

	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
	if (res == NULL) {
		dev_err(&dev->dev, "cannot find IO resource\n");
		ret = -ENOENT;
		goto err;
	}

	size = resource_size(res);

	pd->ioarea = request_mem_region(res->start, size, dev->name);
	if (pd->ioarea == NULL) {
		dev_err(&dev->dev, "cannot request IO\n");
		ret = -ENXIO;
		goto err;
	}

	pd->reg = ioremap(res->start, size);
	if (pd->reg == NULL) {
		dev_err(&dev->dev, "cannot map IO\n");
		ret = -ENXIO;
		goto err_res;
	}

	/* setup the private data */

	pd->adap.owner = THIS_MODULE;
	pd->adap.algo_data = &pd->bit;
	pd->adap.dev.parent = &dev->dev;

	strlcpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name));

	pd->bit.data = pd;
	pd->bit.setsda = simtec_i2c_setsda;
	pd->bit.setscl = simtec_i2c_setscl;
	pd->bit.getsda = simtec_i2c_getsda;
	pd->bit.getscl = simtec_i2c_getscl;
	pd->bit.timeout = HZ;
	pd->bit.udelay = 20;

	ret = i2c_bit_add_bus(&pd->adap);
	if (ret)
		goto err_all;

	return 0;

 err_all:
	iounmap(pd->reg);

 err_res:
	release_resource(pd->ioarea);
	kfree(pd->ioarea);

 err:
	kfree(pd);
	return ret;
}

static int simtec_i2c_remove(struct platform_device *dev)
{
	struct simtec_i2c_data *pd = platform_get_drvdata(dev);

	i2c_del_adapter(&pd->adap);

	iounmap(pd->reg);
	release_resource(pd->ioarea);
	kfree(pd->ioarea);
	kfree(pd);

	return 0;
}

/* device driver */

static struct platform_driver simtec_i2c_driver = {
	.driver		= {
		.name		= "simtec-i2c",
		.owner		= THIS_MODULE,
	},
	.probe		= simtec_i2c_probe,
	.remove		= simtec_i2c_remove,
};

module_platform_driver(simtec_i2c_driver);

MODULE_DESCRIPTION("Simtec Generic I2C Bus driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:simtec-i2c");
Commit	Line	Data
bcda9f1e BD	1	/*
	2	* Copyright (C) 2005 Simtec Electronics
	3	* Ben Dooks <ben@simtec.co.uk>
	4	*
	5	* Simtec Generic I2C Controller
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	19	*/
	20
	21	#include <linux/kernel.h>
	22	#include <linux/module.h>
bcda9f1e BD	23	#include <linux/delay.h>
bcda9f1e BD	24	#include <linux/platform_device.h>
5a0e3ad6	25	#include <linux/slab.h>
21782180	26	#include <linux/io.h>
bcda9f1e BD	27
	28	#include <linux/i2c.h>
	29	#include <linux/i2c-algo-bit.h>
	30
bcda9f1e BD	31	struct simtec_i2c_data {
	32	struct resource *ioarea;
	33	void __iomem *reg;
	34	struct i2c_adapter adap;
	35	struct i2c_algo_bit_data bit;
	36	};
	37
	38	#define CMD_SET_SDA (1<<2)
	39	#define CMD_SET_SCL (1<<3)
	40
	41	#define STATE_SDA (1<<0)
	42	#define STATE_SCL (1<<1)
	43
	44	/* i2c bit-bus functions */
	45
	46	static void simtec_i2c_setsda(void *pw, int state)
	47	{
	48	struct simtec_i2c_data *pd = pw;
	49	writeb(CMD_SET_SDA \| (state ? STATE_SDA : 0), pd->reg);
	50	}
	51
	52	static void simtec_i2c_setscl(void *pw, int state)
	53	{
	54	struct simtec_i2c_data *pd = pw;
	55	writeb(CMD_SET_SCL \| (state ? STATE_SCL : 0), pd->reg);
	56	}
	57
	58	static int simtec_i2c_getsda(void *pw)
	59	{
	60	struct simtec_i2c_data *pd = pw;
	61	return readb(pd->reg) & STATE_SDA ? 1 : 0;
	62	}
	63
	64	static int simtec_i2c_getscl(void *pw)
	65	{
	66	struct simtec_i2c_data *pd = pw;
	67	return readb(pd->reg) & STATE_SCL ? 1 : 0;
	68	}
	69
	70	/* device registration */
	71
	72	static int simtec_i2c_probe(struct platform_device *dev)
	73	{
	74	struct simtec_i2c_data *pd;
	75	struct resource *res;
	76	int size;
	77	int ret;
	78
	79	pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL);
46797a2a	80	if (pd == NULL)
bcda9f1e	81	return -ENOMEM;
bcda9f1e BD	82
	83	platform_set_drvdata(dev, pd);
	84
	85	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
	86	if (res == NULL) {
	87	dev_err(&dev->dev, "cannot find IO resource\n");
	88	ret = -ENOENT;
	89	goto err;
	90	}
	91
59330825	92	size = resource_size(res);
bcda9f1e BD	93
	94	pd->ioarea = request_mem_region(res->start, size, dev->name);
	95	if (pd->ioarea == NULL) {
	96	dev_err(&dev->dev, "cannot request IO\n");
	97	ret = -ENXIO;
	98	goto err;
	99	}
	100
	101	pd->reg = ioremap(res->start, size);
	102	if (pd->reg == NULL) {
	103	dev_err(&dev->dev, "cannot map IO\n");
	104	ret = -ENXIO;
	105	goto err_res;
	106	}
	107
	108	/* setup the private data */
	109
	110	pd->adap.owner = THIS_MODULE;
	111	pd->adap.algo_data = &pd->bit;
	112	pd->adap.dev.parent = &dev->dev;
	113
	114	strlcpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name));
	115
	116	pd->bit.data = pd;
	117	pd->bit.setsda = simtec_i2c_setsda;
	118	pd->bit.setscl = simtec_i2c_setscl;
	119	pd->bit.getsda = simtec_i2c_getsda;
	120	pd->bit.getscl = simtec_i2c_getscl;
	121	pd->bit.timeout = HZ;
	122	pd->bit.udelay = 20;
	123
	124	ret = i2c_bit_add_bus(&pd->adap);
	125	if (ret)
	126	goto err_all;
	127
	128	return 0;
	129
	130	err_all:
	131	iounmap(pd->reg);
	132
	133	err_res:
	134	release_resource(pd->ioarea);
	135	kfree(pd->ioarea);
	136
	137	err:
	138	kfree(pd);
	139	return ret;
	140	}
	141
	142	static int simtec_i2c_remove(struct platform_device *dev)
	143	{
	144	struct simtec_i2c_data *pd = platform_get_drvdata(dev);
	145
	146	i2c_del_adapter(&pd->adap);
	147
	148	iounmap(pd->reg);
	149	release_resource(pd->ioarea);
	150	kfree(pd->ioarea);
	151	kfree(pd);
	152
	153	return 0;
	154	}
	155
bcda9f1e BD	156	/* device driver */
	157
	158	static struct platform_driver simtec_i2c_driver = {
	159	.driver = {
	160	.name = "simtec-i2c",
	161	.owner = THIS_MODULE,
	162	},
	163	.probe = simtec_i2c_probe,
	164	.remove = simtec_i2c_remove,
	165	};
	166
a3664b51	167	module_platform_driver(simtec_i2c_driver);
bcda9f1e BD	168
	169	MODULE_DESCRIPTION("Simtec Generic I2C Bus driver");
	170	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
	171	MODULE_LICENSE("GPL");
a3664b51	172	MODULE_ALIAS("platform:simtec-i2c");