kevin/linux
1
Fork 0
Code
840d8e5e96
linux/drivers/regulator/mc13xxx-regulator-core.c
Jesper Juhl 4b2f67d756 regulator, mc13xxx: Remove pointless test for unsigned less than zero 
The variable 'val' is a 'unsigned int', so it can never be less than zero.
This fact makes the "val < 0" part of the test done in BUG_ON() in
mc13xxx_regulator_get_voltage() rather pointles since it can never have
any effect.
This patch removes the pointless test.

Signed-off-by: Jesper Juhl <jj@chaosbits.net>
Acked-by: Alberto Panizzo <maramaopercheseimorto@gmail.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
2011-02-25 08:51:07 +00:00

242 lines
7.3 KiB
C
Raw Blame History

/*
* Regulator Driver for Freescale MC13xxx PMIC
*
* Copyright 2010 Yong Shen <yong.shen@linaro.org>
*
* Based on mc13783 regulator driver :
* Copyright (C) 2008 Sascha Hauer, Pengutronix <s.hauer@pengutronix.de>
* Copyright 2009 Alberto Panizzo <maramaopercheseimorto@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Regs infos taken from mc13xxx drivers from freescale and mc13xxx.pdf file
* from freescale
*/
#include <linux/mfd/mc13xxx.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/driver.h>
#include <linux/platform_device.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>
#include "mc13xxx.h"
static int mc13xxx_regulator_enable(struct regulator_dev *rdev)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int id = rdev_get_id(rdev);
int ret;
dev_dbg(rdev_get_dev(rdev), "%s id: %d\n", __func__, id);
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_reg_rmw(priv->mc13xxx, mc13xxx_regulators[id].reg,
mc13xxx_regulators[id].enable_bit,
mc13xxx_regulators[id].enable_bit);
mc13xxx_unlock(priv->mc13xxx);
return ret;
}
static int mc13xxx_regulator_disable(struct regulator_dev *rdev)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int id = rdev_get_id(rdev);
int ret;
dev_dbg(rdev_get_dev(rdev), "%s id: %d\n", __func__, id);
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_reg_rmw(priv->mc13xxx, mc13xxx_regulators[id].reg,
mc13xxx_regulators[id].enable_bit, 0);
mc13xxx_unlock(priv->mc13xxx);
return ret;
}
static int mc13xxx_regulator_is_enabled(struct regulator_dev *rdev)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int ret, id = rdev_get_id(rdev);
unsigned int val;
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_reg_read(priv->mc13xxx, mc13xxx_regulators[id].reg, &val);
mc13xxx_unlock(priv->mc13xxx);
if (ret)
return ret;
return (val & mc13xxx_regulators[id].enable_bit) != 0;
}
int mc13xxx_regulator_list_voltage(struct regulator_dev *rdev,
unsigned selector)
{
int id = rdev_get_id(rdev);
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
if (selector >= mc13xxx_regulators[id].desc.n_voltages)
return -EINVAL;
return mc13xxx_regulators[id].voltages[selector];
}
EXPORT_SYMBOL_GPL(mc13xxx_regulator_list_voltage);
int mc13xxx_get_best_voltage_index(struct regulator_dev *rdev,
int min_uV, int max_uV)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int reg_id = rdev_get_id(rdev);
int i;
int bestmatch;
int bestindex;
/*
* Locate the minimum voltage fitting the criteria on
* this regulator. The switchable voltages are not
* in strict falling order so we need to check them
* all for the best match.
*/
bestmatch = INT_MAX;
bestindex = -1;
for (i = 0; i < mc13xxx_regulators[reg_id].desc.n_voltages; i++) {
if (mc13xxx_regulators[reg_id].voltages[i] >= min_uV &&
mc13xxx_regulators[reg_id].voltages[i] < bestmatch) {
bestmatch = mc13xxx_regulators[reg_id].voltages[i];
bestindex = i;
}
}
if (bestindex < 0 || bestmatch > max_uV) {
dev_warn(&rdev->dev, "no possible value for %d<=x<=%d uV\n",
min_uV, max_uV);
return -EINVAL;
}
return bestindex;
}
EXPORT_SYMBOL_GPL(mc13xxx_get_best_voltage_index);
static int mc13xxx_regulator_set_voltage(struct regulator_dev *rdev, int min_uV,
int max_uV, unsigned *selector)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int value, id = rdev_get_id(rdev);
int ret;
dev_dbg(rdev_get_dev(rdev), "%s id: %d min_uV: %d max_uV: %d\n",
__func__, id, min_uV, max_uV);
/* Find the best index */
value = mc13xxx_get_best_voltage_index(rdev, min_uV, max_uV);
dev_dbg(rdev_get_dev(rdev), "%s best value: %d\n", __func__, value);
if (value < 0)
return value;
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_reg_rmw(priv->mc13xxx, mc13xxx_regulators[id].vsel_reg,
mc13xxx_regulators[id].vsel_mask,
value << mc13xxx_regulators[id].vsel_shift);
mc13xxx_unlock(priv->mc13xxx);
return ret;
}
static int mc13xxx_regulator_get_voltage(struct regulator_dev *rdev)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int ret, id = rdev_get_id(rdev);
unsigned int val;
dev_dbg(rdev_get_dev(rdev), "%s id: %d\n", __func__, id);
mc13xxx_lock(priv->mc13xxx);
ret = mc13xxx_reg_read(priv->mc13xxx,
mc13xxx_regulators[id].vsel_reg, &val);
mc13xxx_unlock(priv->mc13xxx);
if (ret)
return ret;
val = (val & mc13xxx_regulators[id].vsel_mask)
>> mc13xxx_regulators[id].vsel_shift;
dev_dbg(rdev_get_dev(rdev), "%s id: %d val: %d\n", __func__, id, val);
BUG_ON(val > mc13xxx_regulators[id].desc.n_voltages);
return mc13xxx_regulators[id].voltages[val];
}
struct regulator_ops mc13xxx_regulator_ops = {
.enable = mc13xxx_regulator_enable,
.disable = mc13xxx_regulator_disable,
.is_enabled = mc13xxx_regulator_is_enabled,
.list_voltage = mc13xxx_regulator_list_voltage,
.set_voltage = mc13xxx_regulator_set_voltage,
.get_voltage = mc13xxx_regulator_get_voltage,
};
EXPORT_SYMBOL_GPL(mc13xxx_regulator_ops);
int mc13xxx_fixed_regulator_set_voltage(struct regulator_dev *rdev, int min_uV,
int max_uV, unsigned *selector)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int id = rdev_get_id(rdev);
dev_dbg(rdev_get_dev(rdev), "%s id: %d min_uV: %d max_uV: %d\n",
__func__, id, min_uV, max_uV);
if (min_uV >= mc13xxx_regulators[id].voltages[0] &&
max_uV <= mc13xxx_regulators[id].voltages[0])
return 0;
else
return -EINVAL;
}
EXPORT_SYMBOL_GPL(mc13xxx_fixed_regulator_set_voltage);
int mc13xxx_fixed_regulator_get_voltage(struct regulator_dev *rdev)
{
struct mc13xxx_regulator_priv *priv = rdev_get_drvdata(rdev);
struct mc13xxx_regulator *mc13xxx_regulators = priv->mc13xxx_regulators;
int id = rdev_get_id(rdev);
dev_dbg(rdev_get_dev(rdev), "%s id: %d\n", __func__, id);
return mc13xxx_regulators[id].voltages[0];
}
EXPORT_SYMBOL_GPL(mc13xxx_fixed_regulator_get_voltage);
struct regulator_ops mc13xxx_fixed_regulator_ops = {
.enable = mc13xxx_regulator_enable,
.disable = mc13xxx_regulator_disable,
.is_enabled = mc13xxx_regulator_is_enabled,
.list_voltage = mc13xxx_regulator_list_voltage,
.set_voltage = mc13xxx_fixed_regulator_set_voltage,
.get_voltage = mc13xxx_fixed_regulator_get_voltage,
};
EXPORT_SYMBOL_GPL(mc13xxx_fixed_regulator_ops);
int mc13xxx_sw_regulator_is_enabled(struct regulator_dev *rdev)
{
return 1;
}
EXPORT_SYMBOL_GPL(mc13xxx_sw_regulator_is_enabled);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Yong Shen <yong.shen@linaro.org>");
MODULE_DESCRIPTION("Regulator Driver for Freescale MC13xxx PMIC");
MODULE_ALIAS("mc13xxx-regulator-core");
View Git Blame Copy Permalink