[linux-2.6-block.git] / drivers / mfd / syscon.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/list.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_data/syscon.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/mfd/syscon.h>
#include <linux/slab.h>

static struct platform_driver syscon_driver;

static DEFINE_SPINLOCK(syscon_list_slock);
static LIST_HEAD(syscon_list);

struct syscon {
	struct device_node *np;
	struct regmap *regmap;
	struct list_head list;
};

static struct regmap_config syscon_regmap_config = {
	.reg_bits = 32,
	.val_bits = 32,
	.reg_stride = 4,
};

static struct syscon *of_syscon_register(struct device_node *np)
{
	struct syscon *syscon;
	struct regmap *regmap;
	void __iomem *base;
	int ret;
	struct regmap_config syscon_config = syscon_regmap_config;

	if (!of_device_is_compatible(np, "syscon"))
		return ERR_PTR(-EINVAL);

	syscon = kzalloc(sizeof(*syscon), GFP_KERNEL);
	if (!syscon)
		return ERR_PTR(-ENOMEM);

	base = of_iomap(np, 0);
	if (!base) {
		ret = -ENOMEM;
		goto err_map;
	}

	/* Parse the device's DT node for an endianness specification */
	if (of_property_read_bool(np, "big-endian"))
		syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
	 else if (of_property_read_bool(np, "little-endian"))
		syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;

	regmap = regmap_init_mmio(NULL, base, &syscon_config);
	if (IS_ERR(regmap)) {
		pr_err("regmap init failed\n");
		ret = PTR_ERR(regmap);
		goto err_regmap;
	}

	syscon->regmap = regmap;
	syscon->np = np;

	spin_lock(&syscon_list_slock);
	list_add_tail(&syscon->list, &syscon_list);
	spin_unlock(&syscon_list_slock);

	return syscon;

err_regmap:
	iounmap(base);
err_map:
	kfree(syscon);
	return ERR_PTR(ret);
}

struct regmap *syscon_node_to_regmap(struct device_node *np)
{
	struct syscon *entry, *syscon = NULL;

	spin_lock(&syscon_list_slock);

	list_for_each_entry(entry, &syscon_list, list)
		if (entry->np == np) {
			syscon = entry;
			break;
		}

	spin_unlock(&syscon_list_slock);

	if (!syscon)
		syscon = of_syscon_register(np);

	if (IS_ERR(syscon))
		return ERR_CAST(syscon);

	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)
{
	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;

	if (property)
		syscon_np = of_parse_phandle(np, property, 0);
	else
		syscon_np = np;

	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 int syscon_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct syscon_platform_data *pdata = dev_get_platdata(dev);
	struct syscon *syscon;
	struct resource *res;
	void __iomem *base;

	syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
	if (!syscon)
		return -ENOMEM;

	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res)
		return -ENOENT;

	base = devm_ioremap(dev, res->start, resource_size(res));
	if (!base)
		return -ENOMEM;

	syscon_regmap_config.max_register = res->end - res->start - 3;
	if (pdata)
		syscon_regmap_config.name = pdata->label;
	syscon->regmap = devm_regmap_init_mmio(dev, 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_dbg(dev, "regmap %pR registered\n", res);

	return 0;
}

static const struct platform_device_id syscon_ids[] = {
	{ "syscon", },
	{ }
};

static struct platform_driver syscon_driver = {
	.driver = {
		.name = "syscon",
	},
	.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");
Commit	Line	Data
87d68730 DA	1	/*
	2	* System Control Driver
	3	*
	4	* Copyright (C) 2012 Freescale Semiconductor, Inc.
	5	* Copyright (C) 2012 Linaro Ltd.
	6	*
	7	* Author: Dong Aisheng <dong.aisheng@linaro.org>
	8	*
	9	* This program is free software; you can redistribute it and/or modify
	10	* it under the terms of the GNU General Public License as published by
	11	* the Free Software Foundation; either version 2 of the License, or
	12	* (at your option) any later version.
	13	*/
	14
	15	#include <linux/err.h>
	16	#include <linux/io.h>
	17	#include <linux/module.h>
bdb0066d	18	#include <linux/list.h>
87d68730 DA	19	#include <linux/of.h>
	20	#include <linux/of_address.h>
	21	#include <linux/of_platform.h>
29f9b6cf	22	#include <linux/platform_data/syscon.h>
87d68730 DA	23	#include <linux/platform_device.h>
87d68730 DA	24	#include <linux/regmap.h>
75177dee	25	#include <linux/mfd/syscon.h>
bdb0066d	26	#include <linux/slab.h>
87d68730 DA	27
	28	static struct platform_driver syscon_driver;
	29
bdb0066d PD	30	static DEFINE_SPINLOCK(syscon_list_slock);
	31	static LIST_HEAD(syscon_list);
	32
87d68730	33	struct syscon {
bdb0066d	34	struct device_node *np;
87d68730	35	struct regmap *regmap;
bdb0066d PD	36	struct list_head list;
	37	};
	38
	39	static struct regmap_config syscon_regmap_config = {
	40	.reg_bits = 32,
	41	.val_bits = 32,
	42	.reg_stride = 4,
87d68730 DA	43	};
87d68730 DA	44
bdb0066d	45	static struct syscon of_syscon_register(struct device_node np)
87d68730	46	{
bdb0066d PD	47	struct syscon *syscon;
	48	struct regmap *regmap;
	49	void __iomem *base;
	50	int ret;
	51	struct regmap_config syscon_config = syscon_regmap_config;
	52
	53	if (!of_device_is_compatible(np, "syscon"))
	54	return ERR_PTR(-EINVAL);
	55
	56	syscon = kzalloc(sizeof(*syscon), GFP_KERNEL);
	57	if (!syscon)
	58	return ERR_PTR(-ENOMEM);
	59
	60	base = of_iomap(np, 0);
	61	if (!base) {
	62	ret = -ENOMEM;
	63	goto err_map;
	64	}
	65
	66	/* Parse the device's DT node for an endianness specification */
	67	if (of_property_read_bool(np, "big-endian"))
	68	syscon_config.val_format_endian = REGMAP_ENDIAN_BIG;
	69	else if (of_property_read_bool(np, "little-endian"))
	70	syscon_config.val_format_endian = REGMAP_ENDIAN_LITTLE;
	71
	72	regmap = regmap_init_mmio(NULL, base, &syscon_config);
	73	if (IS_ERR(regmap)) {
	74	pr_err("regmap init failed\n");
	75	ret = PTR_ERR(regmap);
	76	goto err_regmap;
	77	}
	78
	79	syscon->regmap = regmap;
	80	syscon->np = np;
	81
	82	spin_lock(&syscon_list_slock);
	83	list_add_tail(&syscon->list, &syscon_list);
	84	spin_unlock(&syscon_list_slock);
87d68730	85
bdb0066d PD	86	return syscon;
	87
	88	err_regmap:
	89	iounmap(base);
	90	err_map:
	91	kfree(syscon);
	92	return ERR_PTR(ret);
87d68730 DA	93	}
	94
	95	struct regmap syscon_node_to_regmap(struct device_node np)
	96	{
bdb0066d	97	struct syscon entry, syscon = NULL;
87d68730	98
bdb0066d	99	spin_lock(&syscon_list_slock);
87d68730	100
bdb0066d PD	101	list_for_each_entry(entry, &syscon_list, list)
	102	if (entry->np == np) {
	103	syscon = entry;
	104	break;
	105	}
	106
	107	spin_unlock(&syscon_list_slock);
	108
	109	if (!syscon)
	110	syscon = of_syscon_register(np);
	111
	112	if (IS_ERR(syscon))
	113	return ERR_CAST(syscon);
87d68730 DA	114
	115	return syscon->regmap;
	116	}
	117	EXPORT_SYMBOL_GPL(syscon_node_to_regmap);
	118
	119	struct regmap syscon_regmap_lookup_by_compatible(const char s)
	120	{
	121	struct device_node *syscon_np;
	122	struct regmap *regmap;
	123
	124	syscon_np = of_find_compatible_node(NULL, NULL, s);
	125	if (!syscon_np)
	126	return ERR_PTR(-ENODEV);
	127
	128	regmap = syscon_node_to_regmap(syscon_np);
	129	of_node_put(syscon_np);
	130
	131	return regmap;
	132	}
	133	EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_compatible);
	134
5ab3a89a AS	135	static int syscon_match_pdevname(struct device dev, void data)
5ab3a89a AS	136	{
5ab3a89a AS	137	return !strcmp(dev_name(dev), (const char *)data);
	138	}
	139
	140	struct regmap syscon_regmap_lookup_by_pdevname(const char s)
	141	{
	142	struct device *dev;
	143	struct syscon *syscon;
	144
	145	dev = driver_find_device(&syscon_driver.driver, NULL, (void *)s,
	146	syscon_match_pdevname);
	147	if (!dev)
	148	return ERR_PTR(-EPROBE_DEFER);
	149
	150	syscon = dev_get_drvdata(dev);
	151
	152	return syscon->regmap;
	153	}
	154	EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_pdevname);
	155
87d68730 DA	156	struct regmap syscon_regmap_lookup_by_phandle(struct device_node np,
	157	const char *property)
	158	{
	159	struct device_node *syscon_np;
	160	struct regmap *regmap;
	161
45330bb4 PD	162	if (property)
	163	syscon_np = of_parse_phandle(np, property, 0);
	164	else
	165	syscon_np = np;
	166
87d68730 DA	167	if (!syscon_np)
	168	return ERR_PTR(-ENODEV);
	169
	170	regmap = syscon_node_to_regmap(syscon_np);
	171	of_node_put(syscon_np);
	172
	173	return regmap;
	174	}
	175	EXPORT_SYMBOL_GPL(syscon_regmap_lookup_by_phandle);
	176
f791be49	177	static int syscon_probe(struct platform_device *pdev)
87d68730 DA	178	{
87d68730 DA	179	struct device *dev = &pdev->dev;
29f9b6cf	180	struct syscon_platform_data *pdata = dev_get_platdata(dev);
87d68730	181	struct syscon *syscon;
5ab3a89a	182	struct resource *res;
f10111cc	183	void __iomem *base;
87d68730	184
5ab3a89a	185	syscon = devm_kzalloc(dev, sizeof(*syscon), GFP_KERNEL);
87d68730 DA	186	if (!syscon)
	187	return -ENOMEM;
	188
5ab3a89a AS	189	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	190	if (!res)
	191	return -ENOENT;
87d68730	192
f10111cc AS	193	base = devm_ioremap(dev, res->start, resource_size(res));
f10111cc AS	194	if (!base)
5ab3a89a	195	return -ENOMEM;
87d68730	196
5ab3a89a	197	syscon_regmap_config.max_register = res->end - res->start - 3;
29f9b6cf PM	198	if (pdata)
29f9b6cf PM	199	syscon_regmap_config.name = pdata->label;
f10111cc	200	syscon->regmap = devm_regmap_init_mmio(dev, base,
87d68730 DA	201	&syscon_regmap_config);
	202	if (IS_ERR(syscon->regmap)) {
	203	dev_err(dev, "regmap init failed\n");
	204	return PTR_ERR(syscon->regmap);
	205	}
	206
87d68730 DA	207	platform_set_drvdata(pdev, syscon);
87d68730 DA	208
38d8974e	209	dev_dbg(dev, "regmap %pR registered\n", res);
87d68730 DA	210
	211	return 0;
	212	}
	213
5ab3a89a AS	214	static const struct platform_device_id syscon_ids[] = {
	215	{ "syscon", },
	216	{ }
	217	};
87d68730 DA	218
	219	static struct platform_driver syscon_driver = {
	220	.driver = {
	221	.name = "syscon",
87d68730 DA	222	},
87d68730 DA	223	.probe = syscon_probe,
5ab3a89a	224	.id_table = syscon_ids,
87d68730 DA	225	};
	226
	227	static int __init syscon_init(void)
	228	{
	229	return platform_driver_register(&syscon_driver);
	230	}
	231	postcore_initcall(syscon_init);
	232
	233	static void __exit syscon_exit(void)
	234	{
	235	platform_driver_unregister(&syscon_driver);
	236	}
	237	module_exit(syscon_exit);
	238
	239	MODULE_AUTHOR("Dong Aisheng <dong.aisheng@linaro.org>");
	240	MODULE_DESCRIPTION("System Control driver");
	241	MODULE_LICENSE("GPL v2");