linux/drivers/mfd/syscon.c
Alexander Shiyan 6597619f9c ARM: clps711x: Add support for SYSCON driver
This patch adds support for SYSCON driver for CLPS711X targets.
At this time there are no users for this driver, but it is will
be used as start point to use in CLPS711X drivers and remove
<mach/xx> dependencies.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Olof Johansson <olof@lixom.net>
2013-06-11 15:47:45 -07:00

193 lines
4.3 KiB
C

/*
* System Control Driver
*
* Copyright (C) 2012 Freescale Semiconductor, Inc.
* Copyright (C) 2012 Linaro Ltd.
*
* Author: Dong Aisheng <dong.aisheng@linaro.org>
*
* 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, or
* (at your option) any later version.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
static struct platform_driver syscon_driver;
struct syscon {
void __iomem *base;
struct regmap *regmap;
};
static int syscon_match_node(struct device *dev, void *data)
{
struct device_node *dn = data;
return (dev->of_node == dn) ? 1 : 0;
}
struct regmap *syscon_node_to_regmap(struct device_node *np)
{
struct syscon *syscon;
struct device *dev;
dev = driver_find_device(&syscon_driver.driver, NULL, np,
syscon_match_node);
if (!dev)
return ERR_PTR(-EPROBE_DEFER);
syscon = dev_get_drvdata(dev);
return syscon->regmap;
}
EXPORT_SYMBOL_GPL(syscon_node_to_regmap);
struct regmap *syscon_regmap_lookup_by_compatible(const char *s)
{
struct device_node *syscon_np;
struct regmap *regmap;
syscon_np = of_find_compatible_node(NULL, NULL, s);
if (!syscon_np)
return ERR_PTR(-ENODEV);
regmap = syscon_node_to_regmap(syscon_np);
of_node_put(syscon_np);
return regmap;
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible);
static int syscon_match_pdevname(struct device *dev, void *data)
{
struct platform_device *pdev = to_platform_device(dev);
const struct platform_device_id *id = platform_get_device_id(pdev);
if (id)
if (!strcmp(id->name, (const char *)data))
return 1;
return !strcmp(dev_name(dev), (const char *)data);
}
struct regmap *syscon_regmap_lookup_by_pdevname(const char *s)
{
struct device *dev;
struct syscon *syscon;
dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s,
syscon_match_pdevname);
if (!dev)
return ERR_PTR(-EPROBE_DEFER);
syscon = dev_get_drvdata(dev);
return syscon->regmap;
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_pdevname);
struct regmap *syscon_regmap_lookup_by_phandle(struct device_node *np,
const char *property)
{
struct device_node *syscon_np;
struct regmap *regmap;
syscon_np = of_parse_phandle(np, property, 0);
if (!syscon_np)
return ERR_PTR(-ENODEV);
regmap = syscon_node_to_regmap(syscon_np);
of_node_put(syscon_np);
return regmap;
}
EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle);
static const struct of_device_id of_syscon_match[] = {
{ .compatible = "syscon", },
{ },
};
static struct regmap_config syscon_regmap_config = {
.reg_bits = 32,
.val_bits = 32,
.reg_stride = 4,
};
static int syscon_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct syscon *syscon;
struct resource *res;
syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
if (!syscon)
return -ENOMEM;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res)
return -ENOENT;
syscon->base = devm_ioremap(dev, res->start, resource_size(res));
if (!syscon->base)
return -ENOMEM;
syscon_regmap_config.max_register = res->end - res->start - 3;
syscon->regmap = devm_regmap_init_mmio(dev, syscon->base,
&syscon_regmap_config);
if (IS_ERR(syscon->regmap)) {
dev_err(dev, "regmap init failed\n");
return PTR_ERR(syscon->regmap);
}
platform_set_drvdata(pdev, syscon);
dev_info(dev, "regmap %pR registered\n", res);
return 0;
}
static const struct platform_device_id syscon_ids[] = {
{ "syscon", },
#ifdef CONFIG_ARCH_CLPS711X
{ "clps711x-syscon", },
#endif
{ }
};
static struct platform_driver syscon_driver = {
.driver = {
.name = "syscon",
.owner = THIS_MODULE,
.of_match_table = of_syscon_match,
},
.probe = syscon_probe,
.id_table = syscon_ids,
};
static int __init syscon_init(void)
{
return platform_driver_register(&syscon_driver);
}
postcore_initcall(syscon_init);
static void __exit syscon_exit(void)
{
platform_driver_unregister(&syscon_driver);
}
module_exit(syscon_exit);
MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>");
MODULE_DESCRIPTION("System Control driver");
MODULE_LICENSE("GPL v2");