[people/arne_f/kernel.git] / drivers / i2c / busses / i2c-versatile.c

/*
 *  i2c-versatile.c
 *
 *  Copyright (C) 2006 ARM Ltd.
 *  written by Russell King, Deep Blue Solutions Ltd.
 *
 * 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.
 */
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/i2c-algo-bit.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#include <asm/io.h>

#define I2C_CONTROL	0x00
#define I2C_CONTROLS	0x00
#define I2C_CONTROLC	0x04
#define SCL		(1 << 0)
#define SDA		(1 << 1)

struct i2c_versatile {
	struct i2c_adapter	 adap;
	struct i2c_algo_bit_data algo;
	void __iomem		 *base;
};

static void i2c_versatile_setsda(void *data, int state)
{
	struct i2c_versatile *i2c = data;

	writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
}

static void i2c_versatile_setscl(void *data, int state)
{
	struct i2c_versatile *i2c = data;

	writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
}

static int i2c_versatile_getsda(void *data)
{
	struct i2c_versatile *i2c = data;
	return !!(readl(i2c->base + I2C_CONTROL) & SDA);
}

static int i2c_versatile_getscl(void *data)
{
	struct i2c_versatile *i2c = data;
	return !!(readl(i2c->base + I2C_CONTROL) & SCL);
}

static struct i2c_algo_bit_data i2c_versatile_algo = {
	.setsda	= i2c_versatile_setsda,
	.setscl = i2c_versatile_setscl,
	.getsda	= i2c_versatile_getsda,
	.getscl = i2c_versatile_getscl,
	.udelay	= 30,
	.timeout = HZ,
};

static int i2c_versatile_probe(struct platform_device *dev)
{
	struct i2c_versatile *i2c;
	struct resource *r;
	int ret;

	r = platform_get_resource(dev, IORESOURCE_MEM, 0);
	if (!r) {
		ret = -EINVAL;
		goto err_out;
	}

	if (!request_mem_region(r->start, resource_size(r), "versatile-i2c")) {
		ret = -EBUSY;
		goto err_out;
	}

	i2c = kzalloc(sizeof(struct i2c_versatile), GFP_KERNEL);
	if (!i2c) {
		ret = -ENOMEM;
		goto err_release;
	}

	i2c->base = ioremap(r->start, resource_size(r));
	if (!i2c->base) {
		ret = -ENOMEM;
		goto err_free;
	}

	writel(SCL | SDA, i2c->base + I2C_CONTROLS);

	i2c->adap.owner = THIS_MODULE;
	strlcpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name));
	i2c->adap.algo_data = &i2c->algo;
	i2c->adap.dev.parent = &dev->dev;
	i2c->algo = i2c_versatile_algo;
	i2c->algo.data = i2c;

	if (dev->id >= 0) {
		/* static bus numbering */
		i2c->adap.nr = dev->id;
		ret = i2c_bit_add_numbered_bus(&i2c->adap);
	} else
		/* dynamic bus numbering */
		ret = i2c_bit_add_bus(&i2c->adap);
	if (ret >= 0) {
		platform_set_drvdata(dev, i2c);
		return 0;
	}

	iounmap(i2c->base);
 err_free:
	kfree(i2c);
 err_release:
	release_mem_region(r->start, resource_size(r));
 err_out:
	return ret;
}

static int i2c_versatile_remove(struct platform_device *dev)
{
	struct i2c_versatile *i2c = platform_get_drvdata(dev);

	platform_set_drvdata(dev, NULL);

	i2c_del_adapter(&i2c->adap);
	return 0;
}

static struct platform_driver i2c_versatile_driver = {
	.probe		= i2c_versatile_probe,
	.remove		= i2c_versatile_remove,
	.driver		= {
		.name	= "versatile-i2c",
		.owner	= THIS_MODULE,
	},
};

static int __init i2c_versatile_init(void)
{
	return platform_driver_register(&i2c_versatile_driver);
}

static void __exit i2c_versatile_exit(void)
{
	platform_driver_unregister(&i2c_versatile_driver);
}

subsys_initcall(i2c_versatile_init);
module_exit(i2c_versatile_exit);

MODULE_DESCRIPTION("ARM Versatile I2C bus driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:versatile-i2c");
Commit	Line	Data
6b65cd74 RK	1	/*
	2	* i2c-versatile.c
	3	*
	4	* Copyright (C) 2006 ARM Ltd.
	5	* written by Russell King, Deep Blue Solutions Ltd.
	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 version 2 as
	9	* published by the Free Software Foundation.
	10	*/
	11	#include <linux/kernel.h>
	12	#include <linux/module.h>
	13	#include <linux/i2c.h>
	14	#include <linux/i2c-algo-bit.h>
	15	#include <linux/init.h>
	16	#include <linux/platform_device.h>
5a0e3ad6	17	#include <linux/slab.h>
6b65cd74 RK	18
	19	#include <asm/io.h>
	20
	21	#define I2C_CONTROL 0x00
	22	#define I2C_CONTROLS 0x00
	23	#define I2C_CONTROLC 0x04
	24	#define SCL (1 << 0)
	25	#define SDA (1 << 1)
	26
	27	struct i2c_versatile {
	28	struct i2c_adapter adap;
	29	struct i2c_algo_bit_data algo;
	30	void __iomem *base;
	31	};
	32
	33	static void i2c_versatile_setsda(void *data, int state)
	34	{
	35	struct i2c_versatile *i2c = data;
	36
	37	writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
	38	}
	39
	40	static void i2c_versatile_setscl(void *data, int state)
	41	{
	42	struct i2c_versatile *i2c = data;
	43
	44	writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
	45	}
	46
	47	static int i2c_versatile_getsda(void *data)
	48	{
	49	struct i2c_versatile *i2c = data;
	50	return !!(readl(i2c->base + I2C_CONTROL) & SDA);
	51	}
	52
	53	static int i2c_versatile_getscl(void *data)
	54	{
	55	struct i2c_versatile *i2c = data;
	56	return !!(readl(i2c->base + I2C_CONTROL) & SCL);
	57	}
	58
	59	static struct i2c_algo_bit_data i2c_versatile_algo = {
	60	.setsda = i2c_versatile_setsda,
	61	.setscl = i2c_versatile_setscl,
	62	.getsda = i2c_versatile_getsda,
	63	.getscl = i2c_versatile_getscl,
	64	.udelay = 30,
	65	.timeout = HZ,
	66	};
	67
	68	static int i2c_versatile_probe(struct platform_device *dev)
	69	{
	70	struct i2c_versatile *i2c;
	71	struct resource *r;
	72	int ret;
	73
	74	r = platform_get_resource(dev, IORESOURCE_MEM, 0);
	75	if (!r) {
	76	ret = -EINVAL;
	77	goto err_out;
	78	}
	79
c6ffddea	80	if (!request_mem_region(r->start, resource_size(r), "versatile-i2c")) {
6b65cd74 RK	81	ret = -EBUSY;
	82	goto err_out;
	83	}
	84
	85	i2c = kzalloc(sizeof(struct i2c_versatile), GFP_KERNEL);
	86	if (!i2c) {
	87	ret = -ENOMEM;
	88	goto err_release;
	89	}
	90
c6ffddea	91	i2c->base = ioremap(r->start, resource_size(r));
6b65cd74 RK	92	if (!i2c->base) {
	93	ret = -ENOMEM;
	94	goto err_free;
	95	}
	96
	97	writel(SCL \| SDA, i2c->base + I2C_CONTROLS);
	98
	99	i2c->adap.owner = THIS_MODULE;
	100	strlcpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name));
	101	i2c->adap.algo_data = &i2c->algo;
	102	i2c->adap.dev.parent = &dev->dev;
	103	i2c->algo = i2c_versatile_algo;
	104	i2c->algo.data = i2c;
	105
2514cca0 CM	106	if (dev->id >= 0) {
	107	/* static bus numbering */
	108	i2c->adap.nr = dev->id;
	109	ret = i2c_bit_add_numbered_bus(&i2c->adap);
	110	} else
	111	/* dynamic bus numbering */
	112	ret = i2c_bit_add_bus(&i2c->adap);
6b65cd74 RK	113	if (ret >= 0) {
	114	platform_set_drvdata(dev, i2c);
	115	return 0;
	116	}
	117
	118	iounmap(i2c->base);
	119	err_free:
	120	kfree(i2c);
	121	err_release:
c6ffddea	122	release_mem_region(r->start, resource_size(r));
6b65cd74 RK	123	err_out:
	124	return ret;
	125	}
	126
	127	static int i2c_versatile_remove(struct platform_device *dev)
	128	{
	129	struct i2c_versatile *i2c = platform_get_drvdata(dev);
	130
	131	platform_set_drvdata(dev, NULL);
	132
	133	i2c_del_adapter(&i2c->adap);
	134	return 0;
	135	}
	136
	137	static struct platform_driver i2c_versatile_driver = {
	138	.probe = i2c_versatile_probe,
	139	.remove = i2c_versatile_remove,
	140	.driver = {
	141	.name = "versatile-i2c",
	142	.owner = THIS_MODULE,
	143	},
	144	};
	145
	146	static int __init i2c_versatile_init(void)
	147	{
	148	return platform_driver_register(&i2c_versatile_driver);
	149	}
	150
	151	static void __exit i2c_versatile_exit(void)
	152	{
	153	platform_driver_unregister(&i2c_versatile_driver);
	154	}
	155
2514cca0	156	subsys_initcall(i2c_versatile_init);
6b65cd74 RK	157	module_exit(i2c_versatile_exit);
	158
	159	MODULE_DESCRIPTION("ARM Versatile I2C bus driver");
	160	MODULE_LICENSE("GPL");
add8eda7	161	MODULE_ALIAS("platform:versatile-i2c");