[mirror_ubuntu-artful-kernel.git] / drivers / regulator / fixed.c

/*
 * fixed.c
 *
 * Copyright 2008 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
 *
 * Copyright (c) 2009 Nokia Corporation
 * Roger Quadros <ext-roger.quadros@nokia.com>
 *
 * 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.
 *
 * This is useful for systems with mixed controllable and
 * non-controllable regulators, as well as for allowing testing on
 * systems with no controllable regulators.
 */

#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/fixed.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/machine.h>
#include <linux/acpi.h>
#include <linux/property.h>
#include <linux/gpio/consumer.h>

struct fixed_voltage_data {
	struct regulator_desc desc;
	struct regulator_dev *dev;
};


/**
 * of_get_fixed_voltage_config - extract fixed_voltage_config structure info
 * @dev: device requesting for fixed_voltage_config
 * @desc: regulator description
 *
 * Populates fixed_voltage_config structure by extracting data from device
 * tree node, returns a pointer to the populated structure of NULL if memory
 * alloc fails.
 */
static struct fixed_voltage_config *
of_get_fixed_voltage_config(struct device *dev,
			    const struct regulator_desc *desc)
{
	struct fixed_voltage_config *config;
	struct device_node *np = dev->of_node;
	struct regulator_init_data *init_data;

	config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config),
								 GFP_KERNEL);
	if (!config)
		return ERR_PTR(-ENOMEM);

	config->init_data = of_get_regulator_init_data(dev, dev->of_node, desc);
	if (!config->init_data)
		return ERR_PTR(-EINVAL);

	init_data = config->init_data;
	init_data->constraints.apply_uV = 0;

	config->supply_name = init_data->constraints.name;
	if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
		config->microvolts = init_data->constraints.min_uV;
	} else {
		dev_err(dev,
			 "Fixed regulator specified with variable voltages\n");
		return ERR_PTR(-EINVAL);
	}

	if (init_data->constraints.boot_on)
		config->enabled_at_boot = true;

	config->gpio = of_get_named_gpio(np, "gpio", 0);
	if ((config->gpio < 0) && (config->gpio != -ENOENT))
		return ERR_PTR(config->gpio);

	of_property_read_u32(np, "startup-delay-us", &config->startup_delay);

	config->enable_high = of_property_read_bool(np, "enable-active-high");
	config->gpio_is_open_drain = of_property_read_bool(np,
							   "gpio-open-drain");

	if (of_find_property(np, "vin-supply", NULL))
		config->input_supply = "vin";

	return config;
}

/**
 * acpi_get_fixed_voltage_config - extract fixed_voltage_config structure info
 * @dev: device requesting for fixed_voltage_config
 * @desc: regulator description
 *
 * Populates fixed_voltage_config structure by extracting data through ACPI
 * interface, returns a pointer to the populated structure of NULL if memory
 * alloc fails.
 */
static struct fixed_voltage_config *
acpi_get_fixed_voltage_config(struct device *dev,
			      const struct regulator_desc *desc)
{
	struct fixed_voltage_config *config;
	const char *supply_name;
	struct gpio_desc *gpiod;
	int ret;

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

	ret = device_property_read_string(dev, "supply-name", &supply_name);
	if (!ret)
		config->supply_name = supply_name;

	gpiod = gpiod_get(dev, "gpio", GPIOD_ASIS);
	if (IS_ERR(gpiod))
		return ERR_PTR(-ENODEV);

	config->gpio = desc_to_gpio(gpiod);
	config->enable_high = device_property_read_bool(dev,
							"enable-active-high");
	gpiod_put(gpiod);

	return config;
}

static struct regulator_ops fixed_voltage_ops = {
};

static int reg_fixed_voltage_probe(struct platform_device *pdev)
{
	struct fixed_voltage_config *config;
	struct fixed_voltage_data *drvdata;
	struct regulator_config cfg = { };
	int ret;

	drvdata = devm_kzalloc(&pdev->dev, sizeof(struct fixed_voltage_data),
			       GFP_KERNEL);
	if (!drvdata)
		return -ENOMEM;

	if (pdev->dev.of_node) {
		config = of_get_fixed_voltage_config(&pdev->dev,
						     &drvdata->desc);
		if (IS_ERR(config))
			return PTR_ERR(config);
	} else if (ACPI_HANDLE(&pdev->dev)) {
		config = acpi_get_fixed_voltage_config(&pdev->dev,
						       &drvdata->desc);
		if (IS_ERR(config))
			return PTR_ERR(config);
	} else {
		config = dev_get_platdata(&pdev->dev);
	}

	if (!config)
		return -ENOMEM;

	drvdata->desc.name = devm_kstrdup(&pdev->dev,
					  config->supply_name,
					  GFP_KERNEL);
	if (drvdata->desc.name == NULL) {
		dev_err(&pdev->dev, "Failed to allocate supply name\n");
		return -ENOMEM;
	}
	drvdata->desc.type = REGULATOR_VOLTAGE;
	drvdata->desc.owner = THIS_MODULE;
	drvdata->desc.ops = &fixed_voltage_ops;

	drvdata->desc.enable_time = config->startup_delay;

	if (config->input_supply) {
		drvdata->desc.supply_name = devm_kstrdup(&pdev->dev,
					    config->input_supply,
					    GFP_KERNEL);
		if (!drvdata->desc.supply_name) {
			dev_err(&pdev->dev,
				"Failed to allocate input supply\n");
			return -ENOMEM;
		}
	}

	if (config->microvolts)
		drvdata->desc.n_voltages = 1;

	drvdata->desc.fixed_uV = config->microvolts;

	if (gpio_is_valid(config->gpio)) {
		cfg.ena_gpio = config->gpio;
		if (pdev->dev.of_node)
			cfg.ena_gpio_initialized = true;
	}
	cfg.ena_gpio_invert = !config->enable_high;
	if (config->enabled_at_boot) {
		if (config->enable_high)
			cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
		else
			cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
	} else {
		if (config->enable_high)
			cfg.ena_gpio_flags |= GPIOF_OUT_INIT_LOW;
		else
			cfg.ena_gpio_flags |= GPIOF_OUT_INIT_HIGH;
	}
	if (config->gpio_is_open_drain)
		cfg.ena_gpio_flags |= GPIOF_OPEN_DRAIN;

	cfg.dev = &pdev->dev;
	cfg.init_data = config->init_data;
	cfg.driver_data = drvdata;
	cfg.of_node = pdev->dev.of_node;

	drvdata->dev = devm_regulator_register(&pdev->dev, &drvdata->desc,
					       &cfg);
	if (IS_ERR(drvdata->dev)) {
		ret = PTR_ERR(drvdata->dev);
		dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
		return ret;
	}

	platform_set_drvdata(pdev, drvdata);

	dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
		drvdata->desc.fixed_uV);

	return 0;
}

#if defined(CONFIG_OF)
static const struct of_device_id fixed_of_match[] = {
	{ .compatible = "regulator-fixed", },
	{},
};
MODULE_DEVICE_TABLE(of, fixed_of_match);
#endif

static struct platform_driver regulator_fixed_voltage_driver = {
	.probe		= reg_fixed_voltage_probe,
	.driver		= {
		.name		= "reg-fixed-voltage",
		.of_match_table = of_match_ptr(fixed_of_match),
	},
};

static int __init regulator_fixed_voltage_init(void)
{
	return platform_driver_register(&regulator_fixed_voltage_driver);
}
subsys_initcall(regulator_fixed_voltage_init);

static void __exit regulator_fixed_voltage_exit(void)
{
	platform_driver_unregister(&regulator_fixed_voltage_driver);
}
module_exit(regulator_fixed_voltage_exit);

MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
MODULE_DESCRIPTION("Fixed voltage regulator");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:reg-fixed-voltage");
Commit	Line	Data
4b74ff65 MB	1	/*
	2	* fixed.c
	3	*
	4	* Copyright 2008 Wolfson Microelectronics PLC.
	5	*
	6	* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
	7	*
86d9884b RQ	8	* Copyright (c) 2009 Nokia Corporation
	9	* Roger Quadros <ext-roger.quadros@nokia.com>
	10	*
4b74ff65 MB	11	* This program is free software; you can redistribute it and/or
	12	* modify it under the terms of the GNU General Public License as
	13	* published by the Free Software Foundation; either version 2 of the
	14	* License, or (at your option) any later version.
	15	*
	16	* This is useful for systems with mixed controllable and
	17	* non-controllable regulators, as well as for allowing testing on
	18	* systems with no controllable regulators.
	19	*/
	20
	21	#include <linux/err.h>
	22	#include <linux/mutex.h>
65602c32	23	#include <linux/module.h>
4b74ff65 MB	24	#include <linux/platform_device.h>
	25	#include <linux/regulator/driver.h>
	26	#include <linux/regulator/fixed.h>
86d9884b	27	#include <linux/gpio.h>
5a0e3ad6	28	#include <linux/slab.h>
cef49102 RN	29	#include <linux/of.h>
	30	#include <linux/of_gpio.h>
	31	#include <linux/regulator/of_regulator.h>
	32	#include <linux/regulator/machine.h>
13bed58c LB	33	#include <linux/acpi.h>
	34	#include <linux/property.h>
	35	#include <linux/gpio/consumer.h>
4b74ff65 MB	36
	37	struct fixed_voltage_data {
	38	struct regulator_desc desc;
	39	struct regulator_dev *dev;
4b74ff65 MB	40	};
4b74ff65 MB	41
cef49102 RN	42
	43	/**
	44	* of_get_fixed_voltage_config - extract fixed_voltage_config structure info
	45	* @dev: device requesting for fixed_voltage_config
072e78b1	46	* @desc: regulator description
cef49102 RN	47	*
	48	* Populates fixed_voltage_config structure by extracting data from device
	49	* tree node, returns a pointer to the populated structure of NULL if memory
	50	* alloc fails.
	51	*/
bc91396b	52	static struct fixed_voltage_config *
072e78b1 JMC	53	of_get_fixed_voltage_config(struct device *dev,
072e78b1 JMC	54	const struct regulator_desc *desc)
cef49102 RN	55	{
	56	struct fixed_voltage_config *config;
	57	struct device_node *np = dev->of_node;
cef49102 RN	58	struct regulator_init_data *init_data;
	59
	60	config = devm_kzalloc(dev, sizeof(struct fixed_voltage_config),
	61	GFP_KERNEL);
	62	if (!config)
f141822b	63	return ERR_PTR(-ENOMEM);
cef49102	64
072e78b1	65	config->init_data = of_get_regulator_init_data(dev, dev->of_node, desc);
4b864af1	66	if (!config->init_data)
f141822b	67	return ERR_PTR(-EINVAL);
4b864af1	68
cef49102	69	init_data = config->init_data;
0c437c4a	70	init_data->constraints.apply_uV = 0;
cef49102 RN	71
	72	config->supply_name = init_data->constraints.name;
	73	if (init_data->constraints.min_uV == init_data->constraints.max_uV) {
	74	config->microvolts = init_data->constraints.min_uV;
	75	} else {
	76	dev_err(dev,
	77	"Fixed regulator specified with variable voltages\n");
f141822b	78	return ERR_PTR(-EINVAL);
cef49102 RN	79	}
	80
	81	if (init_data->constraints.boot_on)
	82	config->enabled_at_boot = true;
	83
	84	config->gpio = of_get_named_gpio(np, "gpio", 0);
f5a6d351 LD	85	if ((config->gpio < 0) && (config->gpio != -ENOENT))
f5a6d351 LD	86	return ERR_PTR(config->gpio);
f141822b	87
4127f696	88	of_property_read_u32(np, "startup-delay-us", &config->startup_delay);
cef49102	89
4127f696 SS	90	config->enable_high = of_property_read_bool(np, "enable-active-high");
	91	config->gpio_is_open_drain = of_property_read_bool(np,
	92	"gpio-open-drain");
9a50dba5	93
6be5bfc3 LD	94	if (of_find_property(np, "vin-supply", NULL))
	95	config->input_supply = "vin";
	96
cef49102 RN	97	return config;
	98	}
	99
13bed58c LB	100	/**
	101	* acpi_get_fixed_voltage_config - extract fixed_voltage_config structure info
	102	* @dev: device requesting for fixed_voltage_config
	103	* @desc: regulator description
	104	*
	105	* Populates fixed_voltage_config structure by extracting data through ACPI
	106	* interface, returns a pointer to the populated structure of NULL if memory
	107	* alloc fails.
	108	*/
	109	static struct fixed_voltage_config *
	110	acpi_get_fixed_voltage_config(struct device *dev,
	111	const struct regulator_desc *desc)
	112	{
	113	struct fixed_voltage_config *config;
	114	const char *supply_name;
	115	struct gpio_desc *gpiod;
	116	int ret;
	117
	118	config = devm_kzalloc(dev, sizeof(*config), GFP_KERNEL);
	119	if (!config)
	120	return ERR_PTR(-ENOMEM);
	121
	122	ret = device_property_read_string(dev, "supply-name", &supply_name);
	123	if (!ret)
	124	config->supply_name = supply_name;
	125
	126	gpiod = gpiod_get(dev, "gpio", GPIOD_ASIS);
	127	if (IS_ERR(gpiod))
	128	return ERR_PTR(-ENODEV);
	129
	130	config->gpio = desc_to_gpio(gpiod);
	131	config->enable_high = device_property_read_bool(dev,
	132	"enable-active-high");
	133	gpiod_put(gpiod);
	134
	135	return config;
	136	}
	137
9d442061	138	static struct regulator_ops fixed_voltage_ops = {
9d442061 MB	139	};
9d442061 MB	140
a5023574	141	static int reg_fixed_voltage_probe(struct platform_device *pdev)
4b74ff65	142	{
22d881c0	143	struct fixed_voltage_config *config;
4b74ff65	144	struct fixed_voltage_data *drvdata;
c172708d	145	struct regulator_config cfg = { };
4b74ff65 MB	146	int ret;
4b74ff65 MB	147
072e78b1 JMC	148	drvdata = devm_kzalloc(&pdev->dev, sizeof(struct fixed_voltage_data),
	149	GFP_KERNEL);
	150	if (!drvdata)
	151	return -ENOMEM;
	152
f141822b	153	if (pdev->dev.of_node) {
072e78b1 JMC	154	config = of_get_fixed_voltage_config(&pdev->dev,
072e78b1 JMC	155	&drvdata->desc);
f141822b SW	156	if (IS_ERR(config))
f141822b SW	157	return PTR_ERR(config);
13bed58c LB	158	} else if (ACPI_HANDLE(&pdev->dev)) {
	159	config = acpi_get_fixed_voltage_config(&pdev->dev,
	160	&drvdata->desc);
	161	if (IS_ERR(config))
	162	return PTR_ERR(config);
f141822b	163	} else {
dff91d0b	164	config = dev_get_platdata(&pdev->dev);
f141822b	165	}
22d881c0 AL	166
	167	if (!config)
	168	return -ENOMEM;
cef49102	169
84d0ffbe MB	170	drvdata->desc.name = devm_kstrdup(&pdev->dev,
	171	config->supply_name,
	172	GFP_KERNEL);
4b74ff65	173	if (drvdata->desc.name == NULL) {
c53ad7fe	174	dev_err(&pdev->dev, "Failed to allocate supply name\n");
84d0ffbe	175	return -ENOMEM;
4b74ff65 MB	176	}
	177	drvdata->desc.type = REGULATOR_VOLTAGE;
	178	drvdata->desc.owner = THIS_MODULE;
25a53dfb	179	drvdata->desc.ops = &fixed_voltage_ops;
1c37f8a8	180
3d0f267f MB	181	drvdata->desc.enable_time = config->startup_delay;
3d0f267f MB	182
6be5bfc3	183	if (config->input_supply) {
84d0ffbe MB	184	drvdata->desc.supply_name = devm_kstrdup(&pdev->dev,
	185	config->input_supply,
	186	GFP_KERNEL);
6be5bfc3 LD	187	if (!drvdata->desc.supply_name) {
	188	dev_err(&pdev->dev,
	189	"Failed to allocate input supply\n");
84d0ffbe	190	return -ENOMEM;
6be5bfc3 LD	191	}
	192	}
	193
1c37f8a8 SH	194	if (config->microvolts)
1c37f8a8 SH	195	drvdata->desc.n_voltages = 1;
4b74ff65	196
c368e5fc	197	drvdata->desc.fixed_uV = config->microvolts;
9d442061	198
5315fe2f	199	if (gpio_is_valid(config->gpio)) {
25a53dfb	200	cfg.ena_gpio = config->gpio;
1de3821a MP	201	if (pdev->dev.of_node)
	202	cfg.ena_gpio_initialized = true;
	203	}
25a53dfb MB	204	cfg.ena_gpio_invert = !config->enable_high;
25a53dfb MB	205	if (config->enabled_at_boot) {
609d5f6d	206	if (config->enable_high)
25a53dfb	207	cfg.ena_gpio_flags \|= GPIOF_OUT_INIT_HIGH;
609d5f6d	208	else
25a53dfb	209	cfg.ena_gpio_flags \|= GPIOF_OUT_INIT_LOW;
86d9884b	210	} else {
609d5f6d	211	if (config->enable_high)
25a53dfb	212	cfg.ena_gpio_flags \|= GPIOF_OUT_INIT_LOW;
609d5f6d	213	else
25a53dfb	214	cfg.ena_gpio_flags \|= GPIOF_OUT_INIT_HIGH;
86d9884b	215	}
25a53dfb MB	216	if (config->gpio_is_open_drain)
25a53dfb MB	217	cfg.ena_gpio_flags \|= GPIOF_OPEN_DRAIN;
4b74ff65	218
c172708d MB	219	cfg.dev = &pdev->dev;
	220	cfg.init_data = config->init_data;
	221	cfg.driver_data = drvdata;
	222	cfg.of_node = pdev->dev.of_node;
	223
84d0ffbe MB	224	drvdata->dev = devm_regulator_register(&pdev->dev, &drvdata->desc,
84d0ffbe MB	225	&cfg);
4b74ff65 MB	226	if (IS_ERR(drvdata->dev)) {
4b74ff65 MB	227	ret = PTR_ERR(drvdata->dev);
c53ad7fe	228	dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
84d0ffbe	229	return ret;
4b74ff65 MB	230	}
	231
	232	platform_set_drvdata(pdev, drvdata);
	233
	234	dev_dbg(&pdev->dev, "%s supplying %duV\n", drvdata->desc.name,
c368e5fc	235	drvdata->desc.fixed_uV);
4b74ff65 MB	236
4b74ff65 MB	237	return 0;
4b74ff65 MB	238	}
4b74ff65 MB	239
cef49102	240	#if defined(CONFIG_OF)
3d68dfe3	241	static const struct of_device_id fixed_of_match[] = {
cef49102 RN	242	{ .compatible = "regulator-fixed", },
	243	{},
	244	};
	245	MODULE_DEVICE_TABLE(of, fixed_of_match);
cef49102 RN	246	#endif
cef49102 RN	247
4b74ff65	248	static struct platform_driver regulator_fixed_voltage_driver = {
8ab3343d	249	.probe = reg_fixed_voltage_probe,
4b74ff65 MB	250	.driver = {
4b74ff65 MB	251	.name = "reg-fixed-voltage",
abcfaf23	252	.of_match_table = of_match_ptr(fixed_of_match),
4b74ff65 MB	253	},
	254	};
	255
	256	static int __init regulator_fixed_voltage_init(void)
	257	{
	258	return platform_driver_register(&regulator_fixed_voltage_driver);
	259	}
5a1b22be	260	subsys_initcall(regulator_fixed_voltage_init);
4b74ff65 MB	261
	262	static void __exit regulator_fixed_voltage_exit(void)
	263	{
	264	platform_driver_unregister(&regulator_fixed_voltage_driver);
	265	}
	266	module_exit(regulator_fixed_voltage_exit);
	267
	268	MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
	269	MODULE_DESCRIPTION("Fixed voltage regulator");
	270	MODULE_LICENSE("GPL");
38c53c89	271	MODULE_ALIAS("platform:reg-fixed-voltage");