linux/drivers/i2c/busses/i2c-versatile.c
Karol Lewandowski 44454baa7c i2c: Dynamically assign adapter id if it wasn't explictly specified
Commit 488bf314b ("i2c: Allow i2c_add_numbered_adapter() to assign a
bus id") reworked i2c_add_numbered_adapter() to call i2c_add_adapter()
if requested bus was -1.

This allows to simplify driver's initialization procedure by using
just one function for static and dynamic adapter id registration.

This patch updates few more drivers (missed out in original patch)
to use this functionality.

Signed-off-by: Karol Lewandowski <k.lewandowsk@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
2012-05-12 14:28:11 +02:00

165 lines
3.7 KiB
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>
#include <linux/of_i2c.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);
of_i2c_register_devices(&i2c->adap);
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 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",
.owner = THIS_MODULE,
.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");