alistair23-linux/include/linux/regulator/gpio-regulator.h
Heiko Stübner 3f0292ae8b 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 <heiko@sntech.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2011-10-09 12:36:21 +01:00

88 lines
2.4 KiB
C

/*
* 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