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

/*
 * wm831x-dcdc.c  --  DC-DC buck convertor 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/regulator/machine.h>
#include <linux/gpio.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_BUCKV_MAX_SELECTOR 0x68
#define WM831X_BUCKP_MAX_SELECTOR 0x66

#define WM831X_DCDC_MODE_FAST    0
#define WM831X_DCDC_MODE_NORMAL  1
#define WM831X_DCDC_MODE_IDLE    2
#define WM831X_DCDC_MODE_STANDBY 3

#define WM831X_DCDC_MAX_NAME 9

/* Register offsets in control block */
#define WM831X_DCDC_CONTROL_1     0
#define WM831X_DCDC_CONTROL_2     1
#define WM831X_DCDC_ON_CONFIG     2
#define WM831X_DCDC_SLEEP_CONTROL 3
#define WM831X_DCDC_DVS_CONTROL   4

/*
 * Shared
 */

struct wm831x_dcdc {
	char name[WM831X_DCDC_MAX_NAME];
	char supply_name[WM831X_DCDC_MAX_NAME];
	struct regulator_desc desc;
	int base;
	struct wm831x *wm831x;
	struct regulator_dev *regulator;
	int dvs_gpio;
	int dvs_gpio_state;
	int on_vsel;
	int dvs_vsel;
};

static unsigned int wm831x_dcdc_get_mode(struct regulator_dev *rdev)

{
	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = dcdc->wm831x;
	u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG;
	int val;

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

	val = (val & WM831X_DC1_ON_MODE_MASK) >> WM831X_DC1_ON_MODE_SHIFT;

	switch (val) {
	case WM831X_DCDC_MODE_FAST:
		return REGULATOR_MODE_FAST;
	case WM831X_DCDC_MODE_NORMAL:
		return REGULATOR_MODE_NORMAL;
	case WM831X_DCDC_MODE_STANDBY:
		return REGULATOR_MODE_STANDBY;
	case WM831X_DCDC_MODE_IDLE:
		return REGULATOR_MODE_IDLE;
	default:
		BUG();
		return -EINVAL;
	}
}

static int wm831x_dcdc_set_mode_int(struct wm831x *wm831x, int reg,
				    unsigned int mode)
{
	int val;

	switch (mode) {
	case REGULATOR_MODE_FAST:
		val = WM831X_DCDC_MODE_FAST;
		break;
	case REGULATOR_MODE_NORMAL:
		val = WM831X_DCDC_MODE_NORMAL;
		break;
	case REGULATOR_MODE_STANDBY:
		val = WM831X_DCDC_MODE_STANDBY;
		break;
	case REGULATOR_MODE_IDLE:
		val = WM831X_DCDC_MODE_IDLE;
		break;
	default:
		return -EINVAL;
	}

	return wm831x_set_bits(wm831x, reg, WM831X_DC1_ON_MODE_MASK,
			       val << WM831X_DC1_ON_MODE_SHIFT);
}

static int wm831x_dcdc_set_mode(struct regulator_dev *rdev, unsigned int mode)
{
	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = dcdc->wm831x;
	u16 reg = dcdc->base + WM831X_DCDC_ON_CONFIG;

	return wm831x_dcdc_set_mode_int(wm831x, reg, mode);
}

static int wm831x_dcdc_set_suspend_mode(struct regulator_dev *rdev,
					unsigned int mode)
{
	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = dcdc->wm831x;
	u16 reg = dcdc->base + WM831X_DCDC_SLEEP_CONTROL;

	return wm831x_dcdc_set_mode_int(wm831x, reg, mode);
}

static int wm831x_dcdc_get_status(struct regulator_dev *rdev)
{
	struct wm831x_dcdc *dcdc = rdev_get_drvdata(rdev);
	struct wm831x *wm831x = dcdc->wm831x;
	int ret;

	/* First, check for errors */
	ret = wm831x_reg_read(wm831x, WM831X_DCDC_UV_STATUS);
	if (ret < 0)
		return ret;

	if (ret & (1 << rdev_get_id(rdev))) {
		dev_dbg(wm831x->dev, "DCDC%d under voltage\n",
			rdev_get_id(rdev) + 1);
		return REGULATOR_STATUS_ERROR;
	}

	/* DCDC1 and DCDC2 can additionally detect high voltage/current */
	if (rdev_get_id(rdev) < 2) {
		if (ret & (WM831X_DC1_OV_STS << rdev_get_id(rdev))) {
			dev_dbg(wm831x->