[mirror_ubuntu-bionic-kernel.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/init.h>
#include <linux/delay.h>
#include <linux/platform_device.h>

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

#include <asm/io.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) {
		dev_err(&dev->dev, "cannot allocate private data\n");
		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 = (res->end-res->start)+1;

	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,
};

static int __init i2c_adap_simtec_init(void)
{
	return platform_driver_register(&simtec_i2c_driver);
}

static void __exit i2c_adap_simtec_exit(void)
{
	platform_driver_unregister(&simtec_i2c_driver);
}

module_init(i2c_adap_simtec_init);
module_exit(i2c_adap_simtec_exit);

MODULE_DESCRIPTION("Simtec Generic I2C Bus driver");
MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
MODULE_LICENSE("GPL");
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>
	23	#include <linux/init.h>
	24	#include <linux/delay.h>
	25	#include <linux/platform_device.h>
	26
	27	#include <linux/i2c.h>
	28	#include <linux/i2c-algo-bit.h>
	29
	30	#include <asm/io.h>
	31
	32	struct simtec_i2c_data {
	33	struct resource *ioarea;
	34	void __iomem *reg;
	35	struct i2c_adapter adap;
	36	struct i2c_algo_bit_data bit;
	37	};
	38
	39	#define CMD_SET_SDA (1<<2)
	40	#define CMD_SET_SCL (1<<3)
	41
	42	#define STATE_SDA (1<<0)
	43	#define STATE_SCL (1<<1)
	44
	45	/* i2c bit-bus functions */
	46
	47	static void simtec_i2c_setsda(void *pw, int state)
	48	{
	49	struct simtec_i2c_data *pd = pw;
	50	writeb(CMD_SET_SDA \| (state ? STATE_SDA : 0), pd->reg);
	51	}
	52
	53	static void simtec_i2c_setscl(void *pw, int state)
	54	{
	55	struct simtec_i2c_data *pd = pw;
	56	writeb(CMD_SET_SCL \| (state ? STATE_SCL : 0), pd->reg);
	57	}
	58
	59	static int simtec_i2c_getsda(void *pw)
	60	{
	61	struct simtec_i2c_data *pd = pw;
	62	return readb(pd->reg) & STATE_SDA ? 1 : 0;
	63	}
	64
65	static int simtec_i2c_getscl(void *pw)
66	{
67	struct simtec_i2c_data *pd = pw;
68	return readb(pd->reg) & STATE_SCL ? 1 : 0;
69	}
70
71	/* device registration */
72
73	static int simtec_i2c_probe(struct platform_device *dev)
74	{
75	struct simtec_i2c_data *pd;
76	struct resource *res;
77	int size;
78	int ret;
79
80	pd = kzalloc(sizeof(struct simtec_i2c_data), GFP_KERNEL);
81	if (pd == NULL) {
82	dev_err(&dev->dev, "cannot allocate private data\n");
83	return -ENOMEM;
84	}
85
86	platform_set_drvdata(dev, pd);
87
88	res = platform_get_resource(dev, IORESOURCE_MEM, 0);
89	if (res == NULL) {
90	dev_err(&dev->dev, "cannot find IO resource\n");
91	ret = -ENOENT;
92	goto err;
93	}
94
95	size = (res->end-res->start)+1;
96
97	pd->ioarea = request_mem_region(res->start, size, dev->name);
98	if (pd->ioarea == NULL) {
99	dev_err(&dev->dev, "cannot request IO\n");
100	ret = -ENXIO;
101	goto err;
102	}
103
104	pd->reg = ioremap(res->start, size);
105	if (pd->reg == NULL) {
106	dev_err(&dev->dev, "cannot map IO\n");
107	ret = -ENXIO;
108	goto err_res;
109	}
110
111	/* setup the private data */
112
113	pd->adap.owner = THIS_MODULE;
114	pd->adap.algo_data = &pd->bit;
115	pd->adap.dev.parent = &dev->dev;
116
117	strlcpy(pd->adap.name, "Simtec I2C", sizeof(pd->adap.name));
118
119	pd->bit.data = pd;
120	pd->bit.setsda = simtec_i2c_setsda;
121	pd->bit.setscl = simtec_i2c_setscl;
122	pd->bit.getsda = simtec_i2c_getsda;
123	pd->bit.getscl = simtec_i2c_getscl;
124	pd->bit.timeout = HZ;
125	pd->bit.udelay = 20;
126
127	ret = i2c_bit_add_bus(&pd->adap);
128	if (ret)
129	goto err_all;
130
131	return 0;
132
133	err_all:
134	iounmap(pd->reg);
135
136	err_res:
137	release_resource(pd->ioarea);
138	kfree(pd->ioarea);
139
140	err:
141	kfree(pd);
142	return ret;
143	}
144
145	static int simtec_i2c_remove(struct platform_device *dev)
146	{
147	struct simtec_i2c_data *pd = platform_get_drvdata(dev);
148
149	i2c_del_adapter(&pd->adap);
150
151	iounmap(pd->reg);
152	release_resource(pd->ioarea);
153	kfree(pd->ioarea);
154	kfree(pd);
155
156	return 0;
157	}
158
159
160	/* device driver */
161
162	static struct platform_driver simtec_i2c_driver = {
163	.driver = {
164	.name = "simtec-i2c",
165	.owner = THIS_MODULE,
166	},
167	.probe = simtec_i2c_probe,
168	.remove = simtec_i2c_remove,
169	};
170
171	static int __init i2c_adap_simtec_init(void)
172	{
173	return platform_driver_register(&simtec_i2c_driver);
174	}
175
176	static void __exit i2c_adap_simtec_exit(void)
177	{
178	platform_driver_unregister(&simtec_i2c_driver);
179	}
180
181	module_init(i2c_adap_simtec_init);
182	module_exit(i2c_adap_simtec_exit);
183
184	MODULE_DESCRIPTION("Simtec Generic I2C Bus driver");
185	MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
186	MODULE_LICENSE("GPL");