/*
* Copyright (C) 2011 Freescale Semiconductor, Inc. All Rights Reserved.
*/
/*
* 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.
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <linux/slab.h>
#include <linux/device.h>
#include <linux/module.h>
#include <linux/mfd/syscon.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#define LDO_RAMP_UP_UNIT_IN_CYCLES 64 /* 64 cycles per step */
#define LDO_RAMP_UP_FREQ_IN_MHZ 24 /* cycle based on 24M OSC */
#define LDO_POWER_GATE 0x00
#define LDO_FET_FULL_ON 0x1f
struct anatop_regulator {
const char *name;
u32 control_reg;
struct regmap *anatop;
int vol_bit_shift;
int vol_bit_width;
u32 delay_reg;
int delay_bit_shift;
int delay_bit_width;
int min_bit_val;
int min_voltage;
int max_voltage;
struct regulator_desc rdesc;
struct regulator_init_data *initdata;
bool bypass;
int sel;
};
static int anatop_regmap_set_voltage_time_sel(struct regulator_dev *reg,
unsigned int old_sel,
unsigned int new_sel)
{
struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
u32 val;
int ret = 0;
/* check whether need to care about LDO ramp up speed */
if (anatop_reg->delay_bit_width && new_sel > old_sel) {
/*
* the delay for LDO ramp up time is
* based on the register setting, we need
* to calculate how many steps LDO need to
* ramp up, and how much delay needed. (us)
*/
regmap_read(anatop_reg->anatop, anatop_reg->delay_reg, &val);
val = (val >> anatop_reg->delay_bit_shift) &
((1 << anatop_reg->delay_bit_width) - 1);
ret = (new_sel - old_sel) * (LDO_RAMP_UP_UNIT_IN_CYCLES <<
val) / LDO_RAMP_UP_FREQ_IN_MHZ + 1;
}
return ret;
}
static int anatop_regmap_enable(struct regulator_dev *reg)
{
struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
int sel;
sel = anatop_reg->bypass ? LDO_FET_FULL_ON : anatop_reg->sel;
return regulator_set_voltage_sel_regmap(reg, sel);
}
static int anatop_regmap_disable(struct regulator_dev *reg)
{
return regulator_set_voltage_sel_regmap(reg, LDO_POWER_GATE);
}
static int anatop_regmap_is_enabled(struct regulator_dev *reg)
{
return regulator_get_voltage_sel_regmap(reg) != LDO_POWER_GATE;
}
static int anatop_regmap_core_set_voltage_sel(struct regulator_dev *reg,
unsigned selector)
{
struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
int ret;
if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg)) {
anatop_reg->sel = selector;
return 0;
}
ret = regulator_set_voltage_sel_regmap(reg, selector);
if (!ret)
anatop_reg->sel = selector;
return ret;
}
static int anatop_regmap_core_get_voltage_sel(struct regulator_dev *reg)
{
struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
if (anatop_reg->bypass || !anatop_regmap_is_enabled(reg))
return anatop_reg->sel;
return regulator_get_voltage_sel_regmap(reg);
}
static int anatop_regmap_get_bypass(struct regulator_dev *reg, bool *enable)
{
struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
int sel;
sel = regulator_get_voltage_sel_regmap(reg);
if (sel == LDO_FET_FULL_ON)
WARN_ON(!anatop_reg->bypass);
else if (sel != LDO_POWER_GATE)
WARN_ON(anatop_reg->bypass);
*enable = anatop_reg->bypass;
return 0;
}
static int anatop_regmap_set_bypass(struct regulator_dev *reg, bool enable)
{
struct anatop_regulator *anatop_reg = rdev_get_drvdata(reg);
int sel;
if (enable == anatop_reg->bypass)
return 0;
sel = enable ? LDO_FET_FULL_ON : anatop_reg->sel;
anatop_reg->bypass = enable;
return regulator_set_voltage_sel_regmap(reg, sel);
}
static struct regulator_ops anatop_rops = {
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
};
static struct regulator_ops anatop_core_rops = {
.enable = anatop_regmap_enable,
.disable = anatop_regmap_disable,
.is_enabled = anatop_regmap_is_enabled,
.set_voltage_sel = anatop_regmap_core_set_voltage_sel,
.set_voltage_time_sel = anatop_regmap_set_voltage_time_sel,
.get_voltage_sel = anatop_regmap_core_get_voltage_sel,
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
.get_bypass = anatop_regmap_get_bypass,
.set_bypass = anatop_regmap_set_bypass,
};
static int anatop_regulator_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct device_node *anatop_np;
struct regulator_desc *rdesc;
struct regulator_dev *rdev;
struct anatop_regulator *sreg;
struct regulator_init_data *initdata;
struct regulator_config config = { };
int ret = 0;
u32 val;
sreg = devm_kzalloc(dev, sizeof(*sreg), GFP_KERNEL);
if (!sreg)
return -ENOMEM;
sreg->name = of_get_property(np, "regulator-name", NULL);
rdesc = &sreg->rdesc;
rdesc->name = sreg->name;
rdesc->type = REGULATOR_VOLTAGE;
rdesc->owner = THIS_MODULE;
initdata = of_get_regulator_init_data(dev, np, rdesc);
sreg->initdata = initdata;
anatop_np = of_get_parent(np);
if (!anatop_np)
return -ENODEV;
sreg->anatop = syscon_node_to_regmap(anatop_np);
of_node_put(anatop_np);
if (IS_ERR(sreg->anatop))
return PTR_ERR(sreg->anatop);
ret = of_property_read_u32(np, "anatop-reg-offset",
&sreg->control_reg);
if (ret) {
dev_err(dev, "no anatop-reg-offset property set\n");
return ret;
}
ret = of_property_read_u32(np, "anatop-vol-bit-width",
&sreg->vol_bit_width);
if (ret) {
dev_err(dev, "no anatop-vol-bit-width property set\n");
return ret;
}
ret = of_property_read_u32(np, "anatop-vol-bit-shift",
&sreg->vol_bit_shift);
if (ret) {
dev_err(dev, "no anatop-vol-bit-shift property set\n");
return ret;
}
ret = of_property_read_u32(np, "anatop-min-bit-val",
&sreg->min_bit_val);
if (ret) {
dev_err(dev, "no anatop-min-bit-val property set\n");
return ret;
}
ret = of_property_read_u32(np, "anatop-min-voltage",
&sreg->min_voltage);
if (ret) {
dev_err(dev, "no anatop-min-voltage property set\n");
return ret;
}
ret = of_property_read_u32(np, "anatop-max-voltage",
&sreg->max_voltage);
if (ret) {
dev_err(dev, "no anatop-max-voltage property set\n");
return ret;
}
/* read LDO ramp up setting, only for core reg */
of_property_read_u32(np, "anatop-delay-reg-offset",
&sreg->delay_reg);
of_property_read_u32(np, "anatop-delay-bit-width",
&sreg->delay_bit_width);
of_property_read_u32(np, "anatop-delay-bit-shift",
&sreg->delay_bit_shift);
rdesc->n_voltages = (sreg->max_voltage - sreg->min_voltage) / 25000 + 1
+ sreg->min_bit_val;
rdesc->min_uV = sreg->min_voltage;
rdesc->uV_step = 25000;
rdesc->linear_min_sel = sreg->min_bit_val;
rdesc->vsel_reg = sreg->control_reg;
rdesc->vsel_mask = ((1 << sreg->vol_bit_width) - 1) <<
sreg->vol_bit_shift;
config.dev = &pdev->dev;
config.init_data = initdata;
config.driver_data = sreg;
config.of_node = pdev->dev.of_node;
config.regmap = sreg->anatop;
/* Only core regulators have the ramp up delay configuration. */
if (sreg->control_reg && sreg->delay_bit_width) {
rdesc->ops = &anatop_core_rops;
ret = regmap_read(config.regmap, rdesc->vsel_reg, &val);
if (ret) {
dev_err(dev, "failed to read initial state\n");
return ret;
}
sreg->sel = (val & rdesc->vsel_mask) >> sreg->vol_bit_shift;
if (sreg->sel == LDO_FET_FULL_ON) {
sreg->sel = 0;
sreg->bypass = true;
}
/*
* In case vddpu was disabled by the bootloader, we need to set
* a sane default until imx6-cpufreq was probed and changes the
* voltage to the correct value. In this case we set 1.25V.
*/
if (!sreg->sel && !strcmp(sreg->name, "vddpu"))
sreg->sel = 22;
if (!sreg->sel) {
dev_err(&pdev->dev, "Failed to read a valid default voltage selector.\n");
return -EINVAL;
}
} else {
rdesc->ops = &anatop_rops;
}
/* register regulator */
rdev = devm_regulator_register(dev, rdesc, &config);
if (IS_ERR(rdev)) {
dev_err(dev, "failed to register %s\n",
rdesc->name);
return PTR_ERR(rdev);
}
platform_set_drvdata(pdev, rdev);
return 0;
}
static const struct of_device_id of_anatop_regulator_match_tbl[] = {
{ .compatible = "fsl,anatop-regulator", },
{ /* end */ }
};
static struct platform_driver anatop_regulator_driver = {
.driver = {
.name = "anatop_regulator",
.of_match_table = of_anatop_regulator_match_tbl,
},
.probe = anatop_regulator_probe,
};
static int __init anatop_regulator_init(void)
{
return platform_driver_register(&anatop_regulator_driver);
}
postcore_initcall(anatop_regulator_init);
static void __exit anatop_regulator_exit(void)
{
platform_driver_unregister(&anatop_regulator_driver);
}
module_exit(anatop_regulator_exit);
MODULE_AUTHOR("Nancy Chen <Nancy.Chen@freescale.com>");
MODULE_AUTHOR("Ying-Chun Liu (PaulLiu) <paul.liu@linaro.org>");
MODULE_DESCRIPTION("ANATOP Regulator driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:anatop_regulator");
