diff options
| -rw-r--r-- | drivers/regulator/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/regulator/Makefile | 1 | ||||
| -rw-r--r-- | drivers/regulator/gpio-regulator.c | 357 | ||||
| -rw-r--r-- | include/linux/regulator/gpio-regulator.h | 87 |
4 files changed, 454 insertions, 0 deletions
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index c7fd2c0e3f2b..5e0c7b664732 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -64,6 +64,15 @@ config REGULATOR_USERSPACE_CONSUMER If unsure, say no. +config REGULATOR_GPIO + tristate "GPIO regulator support" + help + This driver provides support for regulators that can be + controlled via gpios. + It is capable of supporting current and voltage regulators + and the platform has to provide a mapping of GPIO-states + to target volts/amps. + config REGULATOR_BQ24022 tristate "TI bq24022 Dual Input 1-Cell Li-Ion Charger IC" help diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index 040d5aa63535..93a6318f5328 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -8,6 +8,7 @@ obj-$(CONFIG_REGULATOR_FIXED_VOLTAGE) += fixed.o obj-$(CONFIG_REGULATOR_VIRTUAL_CONSUMER) += virtual.o obj-$(CONFIG_REGULATOR_USERSPACE_CONSUMER) += userspace-consumer.o +obj-$(CONFIG_REGULATOR_GPIO) += gpio-regulator.o obj-$(CONFIG_REGULATOR_AD5398) += ad5398.o obj-$(CONFIG_REGULATOR_BQ24022) += bq24022.o obj-$(CONFIG_REGULATOR_LP3971) += lp3971.o diff --git a/drivers/regulator/gpio-regulator.c b/drivers/regulator/gpio-regulator.c new file mode 100644 index 000000000000..abf32ad6f573 --- /dev/null +++ b/drivers/regulator/gpio-regulator.c @@ -0,0 +1,357 @@ +/* + * gpio-regulator.c + * + * Copyright 2011 Heiko Stuebner <heiko@sntech.de> + * + * based on 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/platform_device.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/machine.h> +#include <linux/regulator/gpio-regulator.h> +#include <linux/gpio.h> +#include <linux/delay.h> +#include <linux/slab.h> + +struct gpio_regulator_data { + struct regulator_desc desc; + struct regulator_dev *dev; + + int enable_gpio; + bool enable_high; + bool is_enabled; + unsigned startup_delay; + + struct gpio *gpios; + int nr_gpios; + + struct gpio_regulator_state *states; + int nr_states; + + int state; +}; + +static int gpio_regulator_is_enabled(struct regulator_dev *dev) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + + return data->is_enabled; +} + +static int gpio_regulator_enable(struct regulator_dev *dev) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + + if (gpio_is_valid(data->enable_gpio)) { + gpio_set_value_cansleep(data->enable_gpio, data->enable_high); + data->is_enabled = true; + } + + return 0; +} + +static int gpio_regulator_disable(struct regulator_dev *dev) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + + if (gpio_is_valid(data->enable_gpio)) { + gpio_set_value_cansleep(data->enable_gpio, !data->enable_high); + data->is_enabled = false; + } + + return 0; +} + +static int gpio_regulator_enable_time(struct regulator_dev *dev) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + + return data->startup_delay; +} + +static int gpio_regulator_get_value(struct regulator_dev *dev) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + int ptr; + + for (ptr = 0; ptr < data->nr_states; ptr++) + if (data->states[ptr].gpios == data->state) + return data->states[ptr].value; + + return -EINVAL; +} + +static int gpio_regulator_set_value(struct regulator_dev *dev, + int min, int max) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + int ptr, target, state; + + target = -1; + for (ptr = 0; ptr < data->nr_states; ptr++) + if (data->states[ptr].value >= min && + data->states[ptr].value <= max) + target = data->states[ptr].gpios; + + if (target < 0) + return -EINVAL; + + for (ptr = 0; ptr < data->nr_gpios; ptr++) { + state = (target & (1 << ptr)) >> ptr; + gpio_set_value(data->gpios[ptr].gpio, state); + } + data->state = target; + + return 0; +} + +static int gpio_regulator_set_voltage(struct regulator_dev *dev, + int min_uV, int max_uV, + unsigned *selector) +{ + return gpio_regulator_set_value(dev, min_uV, max_uV); +} + +static int gpio_regulator_list_voltage(struct regulator_dev *dev, + unsigned selector) +{ + struct gpio_regulator_data *data = rdev_get_drvdata(dev); + + if (selector >= data->nr_states) + return -EINVAL; + + return data->states[selector].value; +} + +static int gpio_regulator_set_current_limit(struct regulator_dev *dev, + int min_uA, int max_uA) +{ + return gpio_regulator_set_value(dev, min_uA, max_uA); +} + +static struct regulator_ops gpio_regulator_voltage_ops = { + .is_enabled = gpio_regulator_is_enabled, + .enable = gpio_regulator_enable, + .disable = gpio_regulator_disable, + .enable_time = gpio_regulator_enable_time, + .get_voltage = gpio_regulator_get_value, + .set_voltage = gpio_regulator_set_voltage, + .list_voltage = gpio_regulator_list_voltage, +}; + +static struct regulator_ops gpio_regulator_current_ops = { + .is_enabled = gpio_regulator_is_enabled, + .enable = gpio_regulator_enable, + .disable = gpio_regulator_disable, + .enable_time = gpio_regulator_enable_time, + .get_current_limit = gpio_regulator_get_value, + .set_current_limit = gpio_regulator_set_current_limit, +}; + +static int __devinit gpio_regulator_probe(struct platform_device *pdev) +{ + struct gpio_regulator_config *config = pdev->dev.platform_data; + struct gpio_regulator_data *drvdata; + int ptr, ret, state; + + drvdata = kzalloc(sizeof(struct gpio_regulator_data), GFP_KERNEL); + if (drvdata == NULL) { + dev_err(&pdev->dev, "Failed to allocate device data\n"); + return -ENOMEM; + } + + drvdata->desc.name = kstrdup(config->supply_name, GFP_KERNEL); + if (drvdata->desc.name == NULL) { + dev_err(&pdev->dev, "Failed to allocate supply name\n"); + ret = -ENOMEM; + goto err; + } + + drvdata->gpios = kmemdup(config->gpios, + config->nr_gpios * sizeof(struct gpio), + GFP_KERNEL); + if (drvdata->gpios == NULL) { + dev_err(&pdev->dev, "Failed to allocate gpio data\n"); + ret = -ENOMEM; + goto err_name; + } + + drvdata->states = kmemdup(config->states, + config->nr_states * + sizeof(struct gpio_regulator_state), + GFP_KERNEL); + if (drvdata->states == NULL) { + dev_err(&pdev->dev, "Failed to allocate state data\n"); + ret = -ENOMEM; + goto err_memgpio; + } + drvdata->nr_states = config->nr_states; + + drvdata->desc.owner = THIS_MODULE; + + /* handle regulator type*/ + switch (config->type) { + case REGULATOR_VOLTAGE: + drvdata->desc.type = REGULATOR_VOLTAGE; + drvdata->desc.ops = &gpio_regulator_voltage_ops; + drvdata->desc.n_voltages = config->nr_states; + break; + case REGULATOR_CURRENT: + drvdata->desc.type = REGULATOR_CURRENT; + drvdata->desc.ops = &gpio_regulator_current_ops; + break; + default: + dev_err(&pdev->dev, "No regulator type set\n"); + ret = -EINVAL; + goto err_memgpio; + break; + } + + drvdata->enable_gpio = config->enable_gpio; + drvdata->startup_delay = config->startup_delay; + + if (gpio_is_valid(config->enable_gpio)) { + drvdata->enable_high = config->enable_high; + + ret = gpio_request(config->enable_gpio, config->supply_name); + if (ret) { + dev_err(&pdev->dev, + "Could not obtain regulator enable GPIO %d: %d\n", + config->enable_gpio, ret); + goto err_memstate; + } + + /* set output direction without changing state + * to prevent glitch + */ + if (config->enabled_at_boot) { + drvdata->is_enabled = true; + ret = gpio_direction_output(config->enable_gpio, + config->enable_high); + } else { + drvdata->is_enabled = false; + ret = gpio_direction_output(config->enable_gpio, + !config->enable_high); + } + + if (ret) { + dev_err(&pdev->dev, + "Could not configure regulator enable GPIO %d direction: %d\n", + config->enable_gpio, ret); + goto err_enablegpio; + } + } else { + /* Regulator without GPIO control is considered + * always enabled + */ + drvdata->is_enabled = true; + } + + drvdata->nr_gpios = config->nr_gpios; + ret = gpio_request_array(drvdata->gpios, drvdata->nr_gpios); + if (ret) { + dev_err(&pdev->dev, + "Could not obtain regulator setting GPIOs: %d\n", ret); + goto err_enablegpio; + } + + /* build initial state from gpio init data. */ + state = 0; + for (ptr = 0; ptr < drvdata->nr_gpios; ptr++) { + if (config->gpios[ptr].flags & GPIOF_OUT_INIT_HIGH) + state |= (1 << ptr); + } + drvdata->state = state; + + drvdata->dev = regulator_register(&drvdata->desc, &pdev->dev, + config->init_data, drvdata); + if (IS_ERR(drvdata->dev)) { + ret = PTR_ERR(drvdata->dev); + dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret); + goto err_stategpio; + } + + platform_set_drvdata(pdev, drvdata); + + return 0; + +err_stategpio: + gpio_free_array(drvdata->gpios, drvdata->nr_gpios); +err_enablegpio: + if (gpio_is_valid(config->enable_gpio)) + gpio_free(config->enable_gpio); +err_memstate: + kfree(drvdata->states); +err_memgpio: + kfree(drvdata->gpios); +err_name: + kfree(drvdata->desc.name); +err: + kfree(drvdata); + return ret; +} + +static int __devexit gpio_regulator_remove(struct platform_device *pdev) +{ + struct gpio_regulator_data *drvdata = platform_get_drvdata(pdev); + + regulator_unregister(drvdata->dev); + + gpio_free_array(drvdata->gpios, drvdata->nr_gpios); + + kfree(drvdata->states); + kfree(drvdata->gpios); + + if (gpio_is_valid(drvdata->enable_gpio)) + gpio_free(drvdata->enable_gpio); + + kfree(drvdata->desc.name); + kfree(drvdata); + + return 0; +} + +static struct platform_driver gpio_regulator_driver = { + .probe = gpio_regulator_probe, + .remove = __devexit_p(gpio_regulator_remove), + .driver = { + .name = "gpio-regulator", + .owner = THIS_MODULE, + }, +}; + +static int __init gpio_regulator_init(void) +{ + return platform_driver_register(&gpio_regulator_driver); +} +subsys_initcall(gpio_regulator_init); + +static void __exit gpio_regulator_exit(void) +{ + platform_driver_unregister(&gpio_regulator_driver); +} +module_exit(gpio_regulator_exit); + +MODULE_AUTHOR("Heiko Stuebner <heiko@sntech.de>"); +MODULE_DESCRIPTION("gpio voltage regulator"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:gpio-regulator"); diff --git a/include/linux/regulator/gpio-regulator.h b/include/linux/regulator/gpio-regulator.h new file mode 100644 index 000000000000..19fbd267406d --- /dev/null +++ b/include/linux/regulator/gpio-regulator.h @@ -0,0 +1,87 @@ +/* + * gpio-regulator.h + * + * Copyright 2011 Heiko Stuebner <heiko@sntech.de> + * + * based on fixed.h + * + * 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. + */ + +#ifndef __REGULATOR_GPIO_H +#define __REGULATOR_GPIO_H + +struct regulator_init_data; + +enum regulator_type; + +/** + * struct gpio_regulator_state - state description + * @value: microvolts or microamps + * @gpios: bitfield of gpio target-states for the value + * + * This structure describes a supported setting of the regulator + * and the necessary gpio-state to achieve it. + * + * The n-th bit in the bitfield describes the state of the n-th GPIO + * from the gpios-array defined in gpio_regulator_config below. + */ +struct gpio_regulator_state { + int value; + int gpios; +}; + +/** + * struct gpio_regulator_config - config structure + * @supply_name: Name of the regulator supply + * @enable_gpio: GPIO to use for enable control + * set to -EINVAL if not used + * @enable_high: Polarity of enable GPIO + * 1 = Active high, 0 = Active low + * @enabled_at_boot: Whether regulator has been enabled at + * boot or not. 1 = Yes, 0 = No + * This is used to keep the regulator at + * the default state + * @startup_delay: Start-up time in microseconds + * @gpios: Array containing the gpios needed to control + * the setting of the regulator + * @nr_gpios: Number of gpios + * @states: Array of gpio_regulator_state entries describing + * the gpio state for specific voltages + * @nr_states: Number of states available + * @regulator_type: either REGULATOR_CURRENT or REGULATOR_VOLTAGE + * @init_data: regulator_init_data + * + * This structure contains gpio-voltage regulator configuration + * information that must be passed by platform code to the + * gpio-voltage regulator driver. + */ +struct gpio_regulator_config { + const char *supply_name; + + int enable_gpio; + unsigned enable_high:1; + unsigned enabled_at_boot:1; + unsigned startup_delay; + + struct gpio *gpios; + int nr_gpios; + + struct gpio_regulator_state *states; + int nr_states; + + enum regulator_type type; + struct regulator_init_data *init_data; +}; + +#endif |