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v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 *  i2c-versatile.c
  4 *
  5 *  Copyright (C) 2006 ARM Ltd.
  6 *  written by Russell King, Deep Blue Solutions Ltd.
 
 
 
 
  7 */
  8#include <linux/kernel.h>
  9#include <linux/module.h>
 10#include <linux/i2c.h>
 11#include <linux/i2c-algo-bit.h>
 12#include <linux/init.h>
 13#include <linux/platform_device.h>
 14#include <linux/slab.h>
 15#include <linux/io.h>
 16
 17#define I2C_CONTROL	0x00
 18#define I2C_CONTROLS	0x00
 19#define I2C_CONTROLC	0x04
 20#define SCL		(1 << 0)
 21#define SDA		(1 << 1)
 22
 23struct i2c_versatile {
 24	struct i2c_adapter	 adap;
 25	struct i2c_algo_bit_data algo;
 26	void __iomem		 *base;
 27};
 28
 29static void i2c_versatile_setsda(void *data, int state)
 30{
 31	struct i2c_versatile *i2c = data;
 32
 33	writel(SDA, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
 34}
 35
 36static void i2c_versatile_setscl(void *data, int state)
 37{
 38	struct i2c_versatile *i2c = data;
 39
 40	writel(SCL, i2c->base + (state ? I2C_CONTROLS : I2C_CONTROLC));
 41}
 42
 43static int i2c_versatile_getsda(void *data)
 44{
 45	struct i2c_versatile *i2c = data;
 46	return !!(readl(i2c->base + I2C_CONTROL) & SDA);
 47}
 48
 49static int i2c_versatile_getscl(void *data)
 50{
 51	struct i2c_versatile *i2c = data;
 52	return !!(readl(i2c->base + I2C_CONTROL) & SCL);
 53}
 54
 55static const struct i2c_algo_bit_data i2c_versatile_algo = {
 56	.setsda	= i2c_versatile_setsda,
 57	.setscl = i2c_versatile_setscl,
 58	.getsda	= i2c_versatile_getsda,
 59	.getscl = i2c_versatile_getscl,
 60	.udelay	= 30,
 61	.timeout = HZ,
 62};
 63
 64static int i2c_versatile_probe(struct platform_device *dev)
 65{
 66	struct i2c_versatile *i2c;
 
 67	int ret;
 68
 69	i2c = devm_kzalloc(&dev->dev, sizeof(struct i2c_versatile), GFP_KERNEL);
 70	if (!i2c)
 71		return -ENOMEM;
 72
 73	i2c->base = devm_platform_get_and_ioremap_resource(dev, 0, NULL);
 74	if (IS_ERR(i2c->base))
 75		return PTR_ERR(i2c->base);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 76
 77	writel(SCL | SDA, i2c->base + I2C_CONTROLS);
 78
 79	i2c->adap.owner = THIS_MODULE;
 80	strscpy(i2c->adap.name, "Versatile I2C adapter", sizeof(i2c->adap.name));
 81	i2c->adap.algo_data = &i2c->algo;
 82	i2c->adap.dev.parent = &dev->dev;
 83	i2c->adap.dev.of_node = dev->dev.of_node;
 84	i2c->algo = i2c_versatile_algo;
 85	i2c->algo.data = i2c;
 86
 87	i2c->adap.nr = dev->id;
 88	ret = i2c_bit_add_numbered_bus(&i2c->adap);
 89	if (ret < 0)
 90		return ret;
 91
 92	platform_set_drvdata(dev, i2c);
 93
 94	return 0;
 
 
 
 
 
 
 95}
 96
 97static void i2c_versatile_remove(struct platform_device *dev)
 98{
 99	struct i2c_versatile *i2c = platform_get_drvdata(dev);
100
101	i2c_del_adapter(&i2c->adap);
 
102}
103
104static const struct of_device_id i2c_versatile_match[] = {
105	{ .compatible = "arm,versatile-i2c", },
106	{},
107};
108MODULE_DEVICE_TABLE(of, i2c_versatile_match);
109
110static struct platform_driver i2c_versatile_driver = {
111	.probe		= i2c_versatile_probe,
112	.remove		= i2c_versatile_remove,
113	.driver		= {
114		.name	= "versatile-i2c",
 
115		.of_match_table = i2c_versatile_match,
116	},
117};
118
119static int __init i2c_versatile_init(void)
120{
121	return platform_driver_register(&i2c_versatile_driver);
122}
123
124static void __exit i2c_versatile_exit(void)
125{
126	platform_driver_unregister(&i2c_versatile_driver);
127}
128
129subsys_initcall(i2c_versatile_init);
130module_exit(i2c_versatile_exit);
131
132MODULE_DESCRIPTION("ARM Versatile I2C bus driver");
133MODULE_LICENSE("GPL");
134MODULE_ALIAS("platform:versatile-i2c");
v3.15
 
  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>
 17#include <linux/slab.h>
 18#include <linux/io.h>
 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
 26struct i2c_versatile {
 27	struct i2c_adapter	 adap;
 28	struct i2c_algo_bit_data algo;
 29	void __iomem		 *base;
 30};
 31
 32static 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
 39static 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
 46static int i2c_versatile_getsda(void *data)
 47{
 48	struct i2c_versatile *i2c = data;
 49	return !!(readl(i2c->base + I2C_CONTROL) & SDA);
 50}
 51
 52static int i2c_versatile_getscl(void *data)
 53{
 54	struct i2c_versatile *i2c = data;
 55	return !!(readl(i2c->base + I2C_CONTROL) & SCL);
 56}
 57
 58static 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
 67static 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
 79	if (!request_mem_region(r->start, resource_size(r), "versatile-i2c")) {
 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
 90	i2c->base = ioremap(r->start, resource_size(r));
 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;
102	i2c->adap.dev.of_node = dev->dev.of_node;
103	i2c->algo = i2c_versatile_algo;
104	i2c->algo.data = i2c;
105
106	i2c->adap.nr = dev->id;
107	ret = i2c_bit_add_numbered_bus(&i2c->adap);
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:
117	release_mem_region(r->start, resource_size(r));
118 err_out:
119	return ret;
120}
121
122static int i2c_versatile_remove(struct platform_device *dev)
123{
124	struct i2c_versatile *i2c = platform_get_drvdata(dev);
125
126	i2c_del_adapter(&i2c->adap);
127	return 0;
128}
129
130static const struct of_device_id i2c_versatile_match[] = {
131	{ .compatible = "arm,versatile-i2c", },
132	{},
133};
134MODULE_DEVICE_TABLE(of, i2c_versatile_match);
135
136static struct platform_driver i2c_versatile_driver = {
137	.probe		= i2c_versatile_probe,
138	.remove		= i2c_versatile_remove,
139	.driver		= {
140		.name	= "versatile-i2c",
141		.owner	= THIS_MODULE,
142		.of_match_table = i2c_versatile_match,
143	},
144};
145
146static int __init i2c_versatile_init(void)
147{
148	return platform_driver_register(&i2c_versatile_driver);
149}
150
151static void __exit i2c_versatile_exit(void)
152{
153	platform_driver_unregister(&i2c_versatile_driver);
154}
155
156subsys_initcall(i2c_versatile_init);
157module_exit(i2c_versatile_exit);
158
159MODULE_DESCRIPTION("ARM Versatile I2C bus driver");
160MODULE_LICENSE("GPL");
161MODULE_ALIAS("platform:versatile-i2c");