From 8501e757c02e6d30d775e1d4fb4da3ae1bee74bc Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Heiko=20St=C3=BCbner?= Date: Wed, 5 Oct 2011 12:27:05 +0200 Subject: regulator: Add driver for gpio-controlled regulators This patch adds support for regulators that can be controlled via gpios. Examples for such regulators are the TI-tps65024x voltage regulators with 4 fixed and 1 runtime-switchable voltage regulators or the TI-bq240XX charger regulators. The number of controlling gpios is not limited, the mapping between voltage/current and target gpio state is done via the states map and the driver can be used for either voltage or current regulators. A mapping for a regulator with two GPIOs could look like: gpios = { { .gpio = GPIO1, .flags = GPIOF_OUT_INIT_HIGH, .label = "gpio name 1" }, { .gpio = GPIO2, .flags = GPIOF_OUT_INIT_LOW, .label = "gpio name 2" }, } The flags element of the gpios array determines the initial state of the gpio, set during probe. The initial state of the regulator is also calculated from these values states = { { .value = volt_or_cur1, .gpios = (0 << 1) | (0 << 0) }, { .value = volt_or_cur2, .gpios = (0 << 1) | (1 << 0) }, { .value = volt_or_cur3, .gpios = (1 << 1) | (0 << 0) }, { .value = volt_or_cur4, .gpios = (1 << 1) | (1 << 0) }, } The target-state for the n-th gpio is determined by the n-th bit in the bitfield of the target-value. Signed-off-by: Heiko Stuebner Signed-off-by: Mark Brown (cherry picked from commit 3f0292ae8bb100cc8f96106a3de277df48134887) regulator: Add module.h include to gpio-regulator Reported-by: Stephen Rothwell Signed-off-by: Mark Brown (cherry picked from commit ecc37edf7b670616a9dc78a0bdd4911a22d551ec) regulator: Fix compile break due to missing arguments to regulator_register The commit 2c043bcbf287 ("regulator: pass additional of_node to regulator_register()") caused a compile break because it missed updating the regulator_register() call in gpio-regulator.c with the additional parameter (NULL). The compile break as reported by Stephen Rothwell with the x86_64 allmodconfig looked like this drivers/regulator/gpio-regulator.c: In function 'gpio_regulator_probe': drivers/regulator/gpio-regulator.c:287:8: error: too few arguments to function 'regulator_register' include/linux/regulator/driver.h:215:23: note: declared here Reported-by: Stephen Rothwell Signed-off-by: Rajendra Nayak Signed-off-by: Mark Brown (cherry picked from commit 156843470c4b9ea9698cc245d2cff769b3784088) Change-Id: I912886aae825ca440f4ad3e7a33fe4e84bde4e1b Reviewed-on: http://git-master/r/74924 Reviewed-by: Laxman Dewangan Tested-by: Laxman Dewangan Reviewed-on: http://git-master/r/75547 Reviewed-by: Varun Wadekar Tested-by: Varun Wadekar --- drivers/regulator/Kconfig | 9 + drivers/regulator/Makefile | 1 + drivers/regulator/gpio-regulator.c | 358 +++++++++++++++++++++++++++++++++++++ 3 files changed, 368 insertions(+) create mode 100644 drivers/regulator/gpio-regulator.c (limited to 'drivers/regulator') diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 8f52d9c5117e..09d21505c5fb 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 4337283ecc5a..6f54bfd94d49 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..42e1cb1835e5 --- /dev/null +++ b/drivers/regulator/gpio-regulator.c @@ -0,0 +1,358 @@ +/* + * gpio-regulator.c + * + * Copyright 2011 Heiko Stuebner + * + * based on fixed.c + * + * Copyright 2008 Wolfson Microelectronics PLC. + * + * Author: Mark Brown + * + * Copyright (c) 2009 Nokia Corporation + * Roger Quadros + * + * 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 +#include +#include +#include +#include +#include +#include +#include +#include +#include + +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, NULL); + 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 "); +MODULE_DESCRIPTION("gpio voltage regulator"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:gpio-regulator"); -- cgit v1.2.3