[deliverable/linux.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 <linux/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->adap.dev.of_node = dev->dev.of_node;
	i2c->algo = i2c_versatile_algo;
	i2c->algo.data = i2c;

	i2c->adap.nr = dev->id;
	ret = i2c_bit_add_numbered_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);

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

static const struct of_device_id i2c_versatile_match[] = {
	{ .compatible = "arm,versatile-i2c", },
	{},
};
MODULE_DEVICE_TABLE(of, i2c_versatile_match);

static struct platform_driver i2c_versatile_driver = {
	.probe		= i2c_versatile_probe,
	.remove		= i2c_versatile_remove,
	.driver		= {
		.name	= "versatile-i2c",
		.of_match_table = i2c_versatile_match,
	},
};

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>
21782180	18	#include <linux/io.h>
6b65cd74 RK	19
	20	#define I2C_CONTROL 0x00
	21	#define I2C_CONTROLS 0x00
	22	#define I2C_CONTROLC 0x04
	23	#define SCL (1 << 0)
	24	#define SDA (1 << 1)
	25
	26	struct i2c_versatile {
	27	struct i2c_adapter adap;
	28	struct i2c_algo_bit_data algo;
	29	void __iomem *base;
	30	};
	31
	32	static void i2c_versatile_setsda(void *data, int state)
	33	{
	34	struct i2c_versatile *i2c = data;
	35
	36	writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
	37	}
	38
	39	static void i2c_versatile_setscl(void *data, int state)
	40	{
	41	struct i2c_versatile *i2c = data;
	42
	43	writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
	44	}
	45
	46	static int i2c_versatile_getsda(void *data)
	47	{
	48	struct i2c_versatile *i2c = data;
	49	return !!(readl(i2c->base + I2C_CONTROL) & SDA);
	50	}
	51
	52	static int i2c_versatile_getscl(void *data)
	53	{
	54	struct i2c_versatile *i2c = data;
	55	return !!(readl(i2c->base + I2C_CONTROL) & SCL);
	56	}
	57
	58	static struct i2c_algo_bit_data i2c_versatile_algo = {
	59	.setsda = i2c_versatile_setsda,
	60	.setscl = i2c_versatile_setscl,
	61	.getsda = i2c_versatile_getsda,
	62	.getscl = i2c_versatile_getscl,
	63	.udelay = 30,
	64	.timeout = HZ,
	65	};
	66
	67	static int i2c_versatile_probe(struct platform_device *dev)
	68	{
	69	struct i2c_versatile *i2c;
	70	struct resource *r;
	71	int ret;
	72
	73	r = platform_get_resource(dev, IORESOURCE_MEM, 0);
	74	if (!r) {
	75	ret = -EINVAL;
	76	goto err_out;
	77	}
	78
c6ffddea	79	if (!request_mem_region(r->start, resource_size(r), "versatile-i2c")) {
6b65cd74 RK	80	ret = -EBUSY;
	81	goto err_out;
	82	}
	83
	84	i2c = kzalloc(sizeof(struct i2c_versatile), GFP_KERNEL);
	85	if (!i2c) {
	86	ret = -ENOMEM;
	87	goto err_release;
	88	}
	89
c6ffddea	90	i2c->base = ioremap(r->start, resource_size(r));
6b65cd74 RK	91	if (!i2c->base) {
	92	ret = -ENOMEM;
	93	goto err_free;
	94	}
	95
	96	writel(SCL \| SDA, i2c->base + I2C_CONTROLS);
	97
	98	i2c->adap.owner = THIS_MODULE;
	99	strlcpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name));
	100	i2c->adap.algo_data = &i2c->algo;
	101	i2c->adap.dev.parent = &dev->dev;
237ab406	102	i2c->adap.dev.of_node = dev->dev.of_node;
6b65cd74 RK	103	i2c->algo = i2c_versatile_algo;
	104	i2c->algo.data = i2c;
	105
44454baa KL	106	i2c->adap.nr = dev->id;
44454baa KL	107	ret = i2c_bit_add_numbered_bus(&i2c->adap);
6b65cd74 RK	108	if (ret >= 0) {
	109	platform_set_drvdata(dev, i2c);
	110	return 0;
	111	}
	112
	113	iounmap(i2c->base);
	114	err_free:
	115	kfree(i2c);
	116	err_release:
c6ffddea	117	release_mem_region(r->start, resource_size(r));
6b65cd74 RK	118	err_out:
	119	return ret;
	120	}
	121
	122	static int i2c_versatile_remove(struct platform_device *dev)
	123	{
	124	struct i2c_versatile *i2c = platform_get_drvdata(dev);
	125
6b65cd74 RK	126	i2c_del_adapter(&i2c->adap);
	127	return 0;
	128	}
	129
237ab406 PM	130	static const struct of_device_id i2c_versatile_match[] = {
	131	{ .compatible = "arm,versatile-i2c", },
	132	{},
	133	};
	134	MODULE_DEVICE_TABLE(of, i2c_versatile_match);
	135
6b65cd74 RK	136	static struct platform_driver i2c_versatile_driver = {
	137	.probe = i2c_versatile_probe,
	138	.remove = i2c_versatile_remove,
	139	.driver = {
	140	.name = "versatile-i2c",
237ab406	141	.of_match_table = i2c_versatile_match,
6b65cd74 RK	142	},
	143	};
	144
	145	static int __init i2c_versatile_init(void)
	146	{
	147	return platform_driver_register(&i2c_versatile_driver);
	148	}
	149
	150	static void __exit i2c_versatile_exit(void)
	151	{
	152	platform_driver_unregister(&i2c_versatile_driver);
	153	}
	154
2514cca0	155	subsys_initcall(i2c_versatile_init);
6b65cd74 RK	156	module_exit(i2c_versatile_exit);
	157
	158	MODULE_DESCRIPTION("ARM Versatile I2C bus driver");
	159	MODULE_LICENSE("GPL");
add8eda7	160	MODULE_ALIAS("platform:versatile-i2c");