path: root/drivers/regulator/wm831x-ldo.c

/*
 * wm831x-ldo.c  --  LDO driver for the WM831x series
 *
 * Copyright 2009 Wolfson Microelectronics PLC.
 *
 * Author: Mark Brown <broonie@opensource.wolfsonmicro.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.
 */

#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/init.h>
#include <linux/bitops.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/slab.h>

#include <linux/mfd/wm831x/core.h>
#include <linux/mfd/wm831x/regulator.h>
#include <linux/mfd/wm831x/pdata.h>

#define WM831X_LDO_MAX_NAME 6

#define WM831X_LDO_CONTROL       0
#define WM831X_LDO_ON_CONTROL    1
#define WM831X_LDO_SLEEP_CONTROL 2

#define WM831X_ALIVE_LDO_ON_CONTROL    0
#define WM831X_ALIVE_LDO_SLEEP_CONTROL 1

struct wm831x_ldo {
	char name[WM831X_LDO_MAX_NAME];
	struct regulator_desc desc;
	int base;
	struct wm831x *wm831x;
	struct regulator_dev *regulator;
};

/*
 * Shared
 */

static int wm831x_ldo_is_enabled(struct regulator_dev *rdev)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = ldo->wm831x;
	int mask = 1 << rdev_get_id(rdev);
	int reg;

	reg = wm831x_reg_read(wm831x, WM831X_LDO_ENABLE);
	if (reg < 0)
		return reg;

	if (reg & mask)
		return 1;
	else
		return 0;
}

static int wm831x_ldo_enable(struct regulator_dev *rdev)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = ldo->wm831x;
	int mask = 1 << rdev_get_id(rdev);

	return wm831x_set_bits(wm831x, WM831X_LDO_ENABLE, mask, mask);
}

static int wm831x_ldo_disable(struct regulator_dev *rdev)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = ldo->wm831x;
	int mask = 1 << rdev_get_id(rdev);

	return wm831x_set_bits(wm831x, WM831X_LDO_ENABLE, mask, 0);
}

static irqreturn_t wm831x_ldo_uv_irq(int irq, void *data)
{
	struct wm831x_ldo *ldo = data;

	regulator_notifier_call_chain(ldo->regulator,
				      REGULATOR_EVENT_UNDER_VOLTAGE,
				      NULL);

	return IRQ_HANDLED;
}

/*
 * General purpose LDOs
 */

#define WM831X_GP_LDO_SELECTOR_LOW 0xe
#define WM831X_GP_LDO_MAX_SELECTOR 0x1f

static int wm831x_gp_ldo_list_voltage(struct regulator_dev *rdev,
				      unsigned int selector)
{
	/* 0.9-1.6V in 50mV steps */
	if (selector <= WM831X_GP_LDO_SELECTOR_LOW)
		return 900000 + (selector * 50000);
	/* 1.7-3.3V in 50mV steps */
	if (selector <= WM831X_GP_LDO_MAX_SELECTOR)
		return 1600000 + ((selector - WM831X_GP_LDO_SELECTOR_LOW)
				  * 100000);
	return -EINVAL;
}

static int wm831x_gp_ldo_set_voltage_int(struct regulator_dev *rdev, int reg,
					 int min_uV, int max_uV,
					 unsigned *selector)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = ldo->wm831x;
	int vsel, ret;

	if (min_uV < 900000)
		vsel = 0;
	else if (min_uV < 1700000)
		vsel = ((min_uV - 900000) / 50000);
	else
		vsel = ((min_uV - 1700000) / 100000)
			+ WM831X_GP_LDO_SELECTOR_LOW + 1;

	ret = wm831x_gp_ldo_list_voltage(rdev, vsel);
	if (ret < 0)
		return ret;
	if (ret < min_uV || ret > max_uV)
		return -EINVAL;

	*selector = vsel;

	return wm831x_set_bits(wm831x, reg, WM831X_LDO1_ON_VSEL_MASK, vsel);
}

static int wm831x_gp_ldo_set_voltage(struct regulator_dev *rdev,
				     int min_uV, int max_uV,
				     unsigned *selector)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	int reg = ldo->base + WM831X_LDO_ON_CONTROL;

	return wm831x_gp_ldo_set_voltage_int(rdev, reg, min_uV, max_uV,
					     selector);
}

static int wm831x_gp_ldo_set_suspend_voltage(struct regulator_dev *rdev,
					     int uV)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	int reg = ldo->base + WM831X_LDO_SLEEP_CONTROL;
	unsigned int selector;

	return wm831x_gp_ldo_set_voltage_int(rdev, reg, uV, uV, &selector);
}

static int wm831x_gp_ldo_get_voltage_sel(struct regulator_dev *rdev)
{
	struct wm831x_ldo *ldo = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = ldo->wm831x;
	int reg = ldo->base + WM831X_LDO_ON_CONTROL;
	int ret;

	ret = wm831x_reg_read(wm831x, reg);
	if (ret < 0)
		return ret;

	ret &= WM831X_LDO1_ON_VSEL_MASK;

	return ret;
}

static unsigned int wm831x_gp_ldo_get_mode(struct regulator_dev