kernel-ark/drivers/regulator/ab3100.c
Linus Walleij 75f2ba8f00 regulator: Voltage count for AB3100
This sets the number of voltages for the AB3100 regulators so that
they play well with the voltage listing functions and can be used
properly with the MMC regulator integration glue for example.

Signed-off-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
2009-09-17 15:48:24 +02:00

701 lines
17 KiB
C

/*
* drivers/regulator/ab3100.c
*
* Copyright (C) 2008-2009 ST-Ericsson AB
* License terms: GNU General Public License (GPL) version 2
* Low-level control of the AB3100 IC Low Dropout (LDO)
* regulators, external regulator and buck converter
* Author: Mattias Wallin <mattias.wallin@stericsson.com>
* Author: Linus Walleij <linus.walleij@stericsson.com>
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/mfd/ab3100.h>
/* LDO registers and some handy masking definitions for AB3100 */
#define AB3100_LDO_A 0x40
#define AB3100_LDO_C 0x41
#define AB3100_LDO_D 0x42
#define AB3100_LDO_E 0x43
#define AB3100_LDO_E_SLEEP 0x44
#define AB3100_LDO_F 0x45
#define AB3100_LDO_G 0x46
#define AB3100_LDO_H 0x47
#define AB3100_LDO_H_SLEEP_MODE 0
#define AB3100_LDO_H_SLEEP_EN 2
#define AB3100_LDO_ON 4
#define AB3100_LDO_H_VSEL_AC 5
#define AB3100_LDO_K 0x48
#define AB3100_LDO_EXT 0x49
#define AB3100_BUCK 0x4A
#define AB3100_BUCK_SLEEP 0x4B
#define AB3100_REG_ON_MASK 0x10
/**
* struct ab3100_regulator
* A struct passed around the individual regulator functions
* @platform_device: platform device holding this regulator
* @ab3100: handle to the AB3100 parent chip
* @plfdata: AB3100 platform data passed in at probe time
* @regreg: regulator register number in the AB3100
* @fixed_voltage: a fixed voltage for this regulator, if this
* 0 the voltages array is used instead.
* @typ_voltages: an array of available typical voltages for
* this regulator
* @voltages_len: length of the array of available voltages
*/
struct ab3100_regulator {
struct regulator_dev *rdev;
struct ab3100 *ab3100;
struct ab3100_platform_data *plfdata;
u8 regreg;
int fixed_voltage;
int const *typ_voltages;
u8 voltages_len;
};
/* The order in which registers are initialized */
static const u8 ab3100_reg_init_order[AB3100_NUM_REGULATORS+2] = {
AB3100_LDO_A,
AB3100_LDO_C,
AB3100_LDO_E,
AB3100_LDO_E_SLEEP,
AB3100_LDO_F,
AB3100_LDO_G,
AB3100_LDO_H,
AB3100_LDO_K,
AB3100_LDO_EXT,
AB3100_BUCK,
AB3100_BUCK_SLEEP,
AB3100_LDO_D,
};
/* Preset (hardware defined) voltages for these regulators */
#define LDO_A_VOLTAGE 2750000
#define LDO_C_VOLTAGE 2650000
#define LDO_D_VOLTAGE 2650000
static const int const ldo_e_buck_typ_voltages[] = {
1800000,
1400000,
1300000,
1200000,
1100000,
1050000,
900000,
};
static const int const ldo_f_typ_voltages[] = {
1800000,
1400000,
1300000,
1200000,
1100000,
1050000,
2500000,
2650000,
};
static const int const ldo_g_typ_voltages[] = {
2850000,
2750000,
1800000,
1500000,
};
static const int const ldo_h_typ_voltages[] = {
2750000,
1800000,
1500000,
1200000,
};
static const int const ldo_k_typ_voltages[] = {
2750000,
1800000,
};
/* The regulator devices */
static struct ab3100_regulator
ab3100_regulators[AB3100_NUM_REGULATORS] = {
{
.regreg = AB3100_LDO_A,
.fixed_voltage = LDO_A_VOLTAGE,
},
{
.regreg = AB3100_LDO_C,
.fixed_voltage = LDO_C_VOLTAGE,
},
{
.regreg = AB3100_LDO_D,
.fixed_voltage = LDO_D_VOLTAGE,
},
{
.regreg = AB3100_LDO_E,
.typ_voltages = ldo_e_buck_typ_voltages,
.voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
},
{
.regreg = AB3100_LDO_F,
.typ_voltages = ldo_f_typ_voltages,
.voltages_len = ARRAY_SIZE(ldo_f_typ_voltages),
},
{
.regreg = AB3100_LDO_G,
.typ_voltages = ldo_g_typ_voltages,
.voltages_len = ARRAY_SIZE(ldo_g_typ_voltages),
},
{
.regreg = AB3100_LDO_H,
.typ_voltages = ldo_h_typ_voltages,
.voltages_len = ARRAY_SIZE(ldo_h_typ_voltages),
},
{
.regreg = AB3100_LDO_K,
.typ_voltages = ldo_k_typ_voltages,
.voltages_len = ARRAY_SIZE(ldo_k_typ_voltages),
},
{
.regreg = AB3100_LDO_EXT,
/* No voltages for the external regulator */
},
{
.regreg = AB3100_BUCK,
.typ_voltages = ldo_e_buck_typ_voltages,
.voltages_len = ARRAY_SIZE(ldo_e_buck_typ_voltages),
},
};
/*
* General functions for enable, disable and is_enabled used for
* LDO: A,C,E,F,G,H,K,EXT and BUCK
*/
static int ab3100_enable_regulator(struct regulator_dev *reg)
{
struct ab3100_regulator *abreg = reg->reg_data;
int err;
u8 regval;
err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
&regval);
if (err) {
dev_warn(&reg->dev, "failed to get regid %d value\n",
abreg->regreg);
return err;
}
/* The regulator is already on, no reason to go further */
if (regval & AB3100_REG_ON_MASK)
return 0;
regval |= AB3100_REG_ON_MASK;
err = ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
regval);
if (err) {
dev_warn(&reg->dev, "failed to set regid %d value\n",
abreg->regreg);
return err;
}
/* Per-regulator power on delay from spec */
switch (abreg->regreg) {
case AB3100_LDO_A: /* Fallthrough */
case AB3100_LDO_C: /* Fallthrough */
case AB3100_LDO_D: /* Fallthrough */
case AB3100_LDO_E: /* Fallthrough */
case AB3100_LDO_H: /* Fallthrough */
case AB3100_LDO_K:
udelay(200);
break;
case AB3100_LDO_F:
udelay(600);
break;
case AB3100_LDO_G:
udelay(400);
break;
case AB3100_BUCK:
mdelay(1);
break;
default:
break;
}
return 0;
}
static int ab3100_disable_regulator(struct regulator_dev *reg)
{
struct ab3100_regulator *abreg = reg->reg_data;
int err;
u8 regval;
/*
* LDO D is a special regulator. When it is disabled, the entire
* system is shut down. So this is handled specially.
*/
if (abreg->regreg == AB3100_LDO_D) {
int i;
dev_info(&reg->dev, "disabling LDO D - shut down system\n");
/*
* Set regulators to default values, ignore any errors,
* we're going DOWN
*/
for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
(void) ab3100_set_register_interruptible(abreg->ab3100,
ab3100_reg_init_order[i],
abreg->plfdata->reg_initvals[i]);
}
/* Setting LDO D to 0x00 cuts the power to the SoC */
return ab3100_set_register_interruptible(abreg->ab3100,
AB3100_LDO_D, 0x00U);
}
/*
* All other regulators are handled here
*/
err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
&regval);
if (err) {
dev_err(&reg->dev, "unable to get register 0x%x\n",
abreg->regreg);
return err;
}
regval &= ~AB3100_REG_ON_MASK;
return ab3100_set_register_interruptible(abreg->ab3100, abreg->regreg,
regval);
}
static int ab3100_is_enabled_regulator(struct regulator_dev *reg)
{
struct ab3100_regulator *abreg = reg->reg_data;
u8 regval;
int err;
err = ab3100_get_register_interruptible(abreg->ab3100, abreg->regreg,
&regval);
if (err) {
dev_err(&reg->dev, "unable to get register 0x%x\n",
abreg->regreg);
return err;
}
return regval & AB3100_REG_ON_MASK;
}
static int ab3100_list_voltage_regulator(struct regulator_dev *reg,
unsigned selector)
{
struct ab3100_regulator *abreg = reg->reg_data;
if (selector > abreg->voltages_len)
return -EINVAL;
return abreg->typ_voltages[selector];
}
static int ab3100_get_voltage_regulator(struct regulator_dev *reg)
{
struct ab3100_regulator *abreg = reg->reg_data;
u8 regval;
int err;
/* Return the voltage for fixed regulators immediately */
if (abreg->fixed_voltage)
return abreg->fixed_voltage;
/*
* For variable types, read out setting and index into
* supplied voltage list.
*/
err = ab3100_get_register_interruptible(abreg->ab3100,
abreg->regreg, &regval);
if (err) {
dev_warn(&reg->dev,
"failed to get regulator value in register %02x\n",
abreg->regreg);
return err;
}
/* The 3 highest bits index voltages */
regval &= 0xE0;
regval >>= 5;
if (regval > abreg->voltages_len) {
dev_err(&reg->dev,
"regulator register %02x contains an illegal voltage setting\n",
abreg->regreg);
return -EINVAL;
}
return abreg->typ_voltages[regval];
}
static int ab3100_get_best_voltage_index(struct regulator_dev *reg,
int min_uV, int max_uV)
{
struct ab3100_regulator *abreg = reg->reg_data;
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 < abreg->voltages_len; i++) {
if (abreg->typ_voltages[i] <= max_uV &&
abreg->typ_voltages[i] >= min_uV &&
abreg->typ_voltages[i] < bestmatch) {
bestmatch = abreg->typ_voltages[i];
bestindex = i;
}
}
if (bestindex < 0) {
dev_warn(&reg->dev, "requested %d<=x<=%d uV, out of range!\n",
min_uV, max_uV);
return -EINVAL;
}
return bestindex;
}
static int ab3100_set_voltage_regulator(struct regulator_dev *reg,
int min_uV, int max_uV)
{
struct ab3100_regulator *abreg = reg->reg_data;
u8 regval;
int err;
int bestindex;
bestindex = ab3100_get_best_voltage_index(reg, min_uV, max_uV);
if (bestindex < 0)
return bestindex;
err = ab3100_get_register_interruptible(abreg->ab3100,
abreg->regreg, &regval);
if (err) {
dev_warn(&reg->dev,
"failed to get regulator register %02x\n",
abreg->regreg);
return err;
}
/* The highest three bits control the variable regulators */
regval &= ~0xE0;
regval |= (bestindex << 5);
err = ab3100_set_register_interruptible(abreg->ab3100,
abreg->regreg, regval);
if (err)
dev_warn(&reg->dev, "failed to set regulator register %02x\n",
abreg->regreg);
return err;
}
static int ab3100_set_suspend_voltage_regulator(struct regulator_dev *reg,
int uV)
{
struct ab3100_regulator *abreg = reg->reg_data;
u8 regval;
int err;
int bestindex;
u8 targetreg;
if (abreg->regreg == AB3100_LDO_E)
targetreg = AB3100_LDO_E_SLEEP;
else if (abreg->regreg == AB3100_BUCK)
targetreg = AB3100_BUCK_SLEEP;
else
return -EINVAL;
/* LDO E and BUCK have special suspend voltages you can set */
bestindex = ab3100_get_best_voltage_index(reg, uV, uV);
err = ab3100_get_register_interruptible(abreg->ab3100,
targetreg, &regval);
if (err) {
dev_warn(&reg->dev,
"failed to get regulator register %02x\n",
targetreg);
return err;
}
/* The highest three bits control the variable regulators */
regval &= ~0xE0;
regval |= (bestindex << 5);
err = ab3100_set_register_interruptible(abreg->ab3100,
targetreg, regval);
if (err)
dev_warn(&reg->dev, "failed to set regulator register %02x\n",
abreg->regreg);
return err;
}
/*
* The external regulator can just define a fixed voltage.
*/
static int ab3100_get_voltage_regulator_external(struct regulator_dev *reg)
{
struct ab3100_regulator *abreg = reg->reg_data;
return abreg->plfdata->external_voltage;
}
static struct regulator_ops regulator_ops_fixed = {
.enable = ab3100_enable_regulator,
.disable = ab3100_disable_regulator,
.is_enabled = ab3100_is_enabled_regulator,
.get_voltage = ab3100_get_voltage_regulator,
};
static struct regulator_ops regulator_ops_variable = {
.enable = ab3100_enable_regulator,
.disable = ab3100_disable_regulator,
.is_enabled = ab3100_is_enabled_regulator,
.get_voltage = ab3100_get_voltage_regulator,
.set_voltage = ab3100_set_voltage_regulator,
.list_voltage = ab3100_list_voltage_regulator,
};
static struct regulator_ops regulator_ops_variable_sleepable = {
.enable = ab3100_enable_regulator,
.disable = ab3100_disable_regulator,
.is_enabled = ab3100_is_enabled_regulator,
.get_voltage = ab3100_get_voltage_regulator,
.set_voltage = ab3100_set_voltage_regulator,
.set_suspend_voltage = ab3100_set_suspend_voltage_regulator,
.list_voltage = ab3100_list_voltage_regulator,
};
/*
* LDO EXT is an external regulator so it is really
* not possible to set any voltage locally here, AB3100
* is an on/off switch plain an simple. The external
* voltage is defined in the board set-up if any.
*/
static struct regulator_ops regulator_ops_external = {
.enable = ab3100_enable_regulator,
.disable = ab3100_disable_regulator,
.is_enabled = ab3100_is_enabled_regulator,
.get_voltage = ab3100_get_voltage_regulator_external,
};
static struct regulator_desc
ab3100_regulator_desc[AB3100_NUM_REGULATORS] = {
{
.name = "LDO_A",
.id = AB3100_LDO_A,
.ops = &regulator_ops_fixed,
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_C",
.id = AB3100_LDO_C,
.ops = &regulator_ops_fixed,
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_D",
.id = AB3100_LDO_D,
.ops = &regulator_ops_fixed,
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_E",
.id = AB3100_LDO_E,
.ops = &regulator_ops_variable_sleepable,
.n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_F",
.id = AB3100_LDO_F,
.ops = &regulator_ops_variable,
.n_voltages = ARRAY_SIZE(ldo_f_typ_voltages),
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_G",
.id = AB3100_LDO_G,
.ops = &regulator_ops_variable,
.n_voltages = ARRAY_SIZE(ldo_g_typ_voltages),
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_H",
.id = AB3100_LDO_H,
.ops = &regulator_ops_variable,
.n_voltages = ARRAY_SIZE(ldo_h_typ_voltages),
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_K",
.id = AB3100_LDO_K,
.ops = &regulator_ops_variable,
.n_voltages = ARRAY_SIZE(ldo_k_typ_voltages),
.type = REGULATOR_VOLTAGE,
},
{
.name = "LDO_EXT",
.id = AB3100_LDO_EXT,
.ops = &regulator_ops_external,
.type = REGULATOR_VOLTAGE,
},
{
.name = "BUCK",
.id = AB3100_BUCK,
.ops = &regulator_ops_variable_sleepable,
.n_voltages = ARRAY_SIZE(ldo_e_buck_typ_voltages),
.type = REGULATOR_VOLTAGE,
},
};
/*
* NOTE: the following functions are regulators pluralis - it is the
* binding to the AB3100 core driver and the parent platform device
* for all the different regulators.
*/
static int __init ab3100_regulators_probe(struct platform_device *pdev)
{
struct ab3100_platform_data *plfdata = pdev->dev.platform_data;
struct ab3100 *ab3100 = platform_get_drvdata(pdev);
int err = 0;
u8 data;
int i;
/* Check chip state */
err = ab3100_get_register_interruptible(ab3100,
AB3100_LDO_D, &data);
if (err) {
dev_err(&pdev->dev, "could not read initial status of LDO_D\n");
return err;
}
if (data & 0x10)
dev_notice(&pdev->dev,
"chip is already in active mode (Warm start)\n");
else
dev_notice(&pdev->dev,
"chip is in inactive mode (Cold start)\n");
/* Set up regulators */
for (i = 0; i < ARRAY_SIZE(ab3100_reg_init_order); i++) {
err = ab3100_set_register_interruptible(ab3100,
ab3100_reg_init_order[i],
plfdata->reg_initvals[i]);
if (err) {
dev_err(&pdev->dev, "regulator initialization failed with error %d\n",
err);
return err;
}
}
if (err) {
dev_err(&pdev->dev,
"LDO D regulator initialization failed with error %d\n",
err);
return err;
}
/* Register the regulators */
for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
struct ab3100_regulator *reg = &ab3100_regulators[i];
struct regulator_dev *rdev;
/*
* Initialize per-regulator struct.
* Inherit platform data, this comes down from the
* i2c boarddata, from the machine. So if you want to
* see what it looks like for a certain machine, go
* into the machine I2C setup.
*/
reg->ab3100 = ab3100;
reg->plfdata = plfdata;
/*
* Register the regulator, pass around
* the ab3100_regulator struct
*/
rdev = regulator_register(&ab3100_regulator_desc[i],
&pdev->dev,
&plfdata->reg_constraints[i],
reg);
if (IS_ERR(rdev)) {
err = PTR_ERR(rdev);
dev_err(&pdev->dev,
"%s: failed to register regulator %s err %d\n",
__func__, ab3100_regulator_desc[i].name,
err);
i--;
/* remove the already registered regulators */
while (i > 0) {
regulator_unregister(ab3100_regulators[i].rdev);
i--;
}
return err;
}
/* Then set a pointer back to the registered regulator */
reg->rdev = rdev;
}
return 0;
}
static int __exit ab3100_regulators_remove(struct platform_device *pdev)
{
int i;
for (i = 0; i < AB3100_NUM_REGULATORS; i++) {
struct ab3100_regulator *reg = &ab3100_regulators[i];
regulator_unregister(reg->rdev);
}
return 0;
}
static struct platform_driver ab3100_regulators_driver = {
.driver = {
.name = "ab3100-regulators",
.owner = THIS_MODULE,
},
.probe = ab3100_regulators_probe,
.remove = __exit_p(ab3100_regulators_remove),
};
static __init int ab3100_regulators_init(void)
{
return platform_driver_register(&ab3100_regulators_driver);
}
static __exit void ab3100_regulators_exit(void)
{
platform_driver_register(&ab3100_regulators_driver);
}
subsys_initcall(ab3100_regulators_init);
module_exit(ab3100_regulators_exit);
MODULE_AUTHOR("Mattias Wallin <mattias.wallin@stericsson.com>");
MODULE_DESCRIPTION("AB3100 Regulator driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ab3100-regulators");