linux-next/drivers/regulator/lm363x-regulator.c
Douglas Anderson 259b93b21a
regulator: Set PROBE_PREFER_ASYNCHRONOUS for drivers that existed in 4.14
Probing of regulators can be a slow operation and can contribute to
slower boot times. This is especially true if a regulator is turned on
at probe time (with regulator-boot-on or regulator-always-on) and the
regulator requires delays (off-on-time, ramp time, etc).

While the overall kernel is not ready to switch to async probe by
default, as per the discussion on the mailing lists [1] it is believed
that the regulator subsystem is in good shape and we can move
regulator drivers over wholesale. There is no way to just magically
opt in all regulators (regulators are just normal drivers like
platform_driver), so we set PROBE_PREFER_ASYNCHRONOUS for all
regulators found in 'drivers/regulator' individually.

Given the number of drivers touched and the impossibility to test this
ahead of time, it wouldn't be shocking at all if this caused a
regression for someone. If there is a regression caused by this patch,
it's likely to be one of the cases talked about in [1]. As a "quick
fix", drivers involved in the regression could be fixed by changing
them to PROBE_FORCE_SYNCHRONOUS. That being said, the correct fix
would be to directly fix the problem that caused the issue with async
probe.

The approach here follows a similar approach that was used for the mmc
subsystem several years ago [2]. In fact, I ran nearly the same python
script to auto-generate the changes. The only thing I changed was to
search for "i2c_driver", "spmi_driver", and "spi_driver" in addition
to "platform_driver".

[1] https://lore.kernel.org/r/06db017f-e985-4434-8d1d-02ca2100cca0@sirena.org.uk
[2] https://lore.kernel.org/r/20200903232441.2694866-1-dianders@chromium.org/

Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20230316125351.1.I2a4677392a38db5758dee0788b2cea5872562a82@changeid
Signed-off-by: Mark Brown <broonie@kernel.org>
2023-03-20 13:11:25 +00:00

368 lines
10 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* TI LM363X Regulator Driver
*
* Copyright 2015 Texas Instruments
*
* Author: Milo Kim <milo.kim@ti.com>
*/
#include <linux/err.h>
#include <linux/kernel.h>
#include <linux/mfd/ti-lmu.h>
#include <linux/mfd/ti-lmu-register.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/platform_device.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#include <linux/slab.h>
/* LM3631 */
#define LM3631_BOOST_VSEL_MAX 0x25
#define LM3631_LDO_VSEL_MAX 0x28
#define LM3631_CONT_VSEL_MAX 0x03
#define LM3631_VBOOST_MIN 4500000
#define LM3631_VCONT_MIN 1800000
#define LM3631_VLDO_MIN 4000000
#define ENABLE_TIME_USEC 1000
/* LM3632 */
#define LM3632_BOOST_VSEL_MAX 0x26
#define LM3632_LDO_VSEL_MAX 0x28
#define LM3632_VBOOST_MIN 4500000
#define LM3632_VLDO_MIN 4000000
/* LM36274 */
#define LM36274_BOOST_VSEL_MAX 0x3f
#define LM36274_LDO_VSEL_MAX 0x32
#define LM36274_VOLTAGE_MIN 4000000
/* Common */
#define LM363X_STEP_50mV 50000
#define LM363X_STEP_500mV 500000
static const int ldo_cont_enable_time[] = {
0, 2000, 5000, 10000, 20000, 50000, 100000, 200000,
};
static int lm363x_regulator_enable_time(struct regulator_dev *rdev)
{
enum lm363x_regulator_id id = rdev_get_id(rdev);
unsigned int val, addr, mask;
switch (id) {
case LM3631_LDO_CONT:
addr = LM3631_REG_ENTIME_VCONT;
mask = LM3631_ENTIME_CONT_MASK;
break;
case LM3631_LDO_OREF:
addr = LM3631_REG_ENTIME_VOREF;
mask = LM3631_ENTIME_MASK;
break;
case LM3631_LDO_POS:
addr = LM3631_REG_ENTIME_VPOS;
mask = LM3631_ENTIME_MASK;
break;
case LM3631_LDO_NEG:
addr = LM3631_REG_ENTIME_VNEG;
mask = LM3631_ENTIME_MASK;
break;
default:
return 0;
}
if (regmap_read(rdev->regmap, addr, &val))
return -EINVAL;
val = (val & mask) >> LM3631_ENTIME_SHIFT;
if (id == LM3631_LDO_CONT)
return ldo_cont_enable_time[val];
else
return ENABLE_TIME_USEC * val;
}
static const struct regulator_ops lm363x_boost_voltage_table_ops = {
.list_voltage = regulator_list_voltage_linear,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
};
static const struct regulator_ops lm363x_regulator_voltage_table_ops = {
.list_voltage = regulator_list_voltage_linear,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
.enable_time = lm363x_regulator_enable_time,
};
static const struct regulator_desc lm363x_regulator_desc[] = {
/* LM3631 */
{
.name = "vboost",
.of_match = "vboost",
.id = LM3631_BOOST,
.ops = &lm363x_boost_voltage_table_ops,
.n_voltages = LM3631_BOOST_VSEL_MAX + 1,
.min_uV = LM3631_VBOOST_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3631_REG_VOUT_BOOST,
.vsel_mask = LM3631_VOUT_MASK,
},
{
.name = "ldo_cont",
.of_match = "vcont",
.id = LM3631_LDO_CONT,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM3631_CONT_VSEL_MAX + 1,
.min_uV = LM3631_VCONT_MIN,
.uV_step = LM363X_STEP_500mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3631_REG_VOUT_CONT,
.vsel_mask = LM3631_VOUT_CONT_MASK,
.enable_reg = LM3631_REG_LDO_CTRL2,
.enable_mask = LM3631_EN_CONT_MASK,
},
{
.name = "ldo_oref",
.of_match = "voref",
.id = LM3631_LDO_OREF,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM3631_LDO_VSEL_MAX + 1,
.min_uV = LM3631_VLDO_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3631_REG_VOUT_OREF,
.vsel_mask = LM3631_VOUT_MASK,
.enable_reg = LM3631_REG_LDO_CTRL1,
.enable_mask = LM3631_EN_OREF_MASK,
},
{
.name = "ldo_vpos",
.of_match = "vpos",
.id = LM3631_LDO_POS,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM3631_LDO_VSEL_MAX + 1,
.min_uV = LM3631_VLDO_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3631_REG_VOUT_POS,
.vsel_mask = LM3631_VOUT_MASK,
.enable_reg = LM3631_REG_LDO_CTRL1,
.enable_mask = LM3631_EN_VPOS_MASK,
},
{
.name = "ldo_vneg",
.of_match = "vneg",
.id = LM3631_LDO_NEG,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM3631_LDO_VSEL_MAX + 1,
.min_uV = LM3631_VLDO_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3631_REG_VOUT_NEG,
.vsel_mask = LM3631_VOUT_MASK,
.enable_reg = LM3631_REG_LDO_CTRL1,
.enable_mask = LM3631_EN_VNEG_MASK,
},
/* LM3632 */
{
.name = "vboost",
.of_match = "vboost",
.id = LM3632_BOOST,
.ops = &lm363x_boost_voltage_table_ops,
.n_voltages = LM3632_BOOST_VSEL_MAX + 1,
.min_uV = LM3632_VBOOST_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3632_REG_VOUT_BOOST,
.vsel_mask = LM3632_VOUT_MASK,
},
{
.name = "ldo_vpos",
.of_match = "vpos",
.id = LM3632_LDO_POS,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM3632_LDO_VSEL_MAX + 1,
.min_uV = LM3632_VLDO_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3632_REG_VOUT_POS,
.vsel_mask = LM3632_VOUT_MASK,
.enable_reg = LM3632_REG_BIAS_CONFIG,
.enable_mask = LM3632_EN_VPOS_MASK,
},
{
.name = "ldo_vneg",
.of_match = "vneg",
.id = LM3632_LDO_NEG,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM3632_LDO_VSEL_MAX + 1,
.min_uV = LM3632_VLDO_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM3632_REG_VOUT_NEG,
.vsel_mask = LM3632_VOUT_MASK,
.enable_reg = LM3632_REG_BIAS_CONFIG,
.enable_mask = LM3632_EN_VNEG_MASK,
},
/* LM36274 */
{
.name = "vboost",
.of_match = "vboost",
.id = LM36274_BOOST,
.ops = &lm363x_boost_voltage_table_ops,
.n_voltages = LM36274_BOOST_VSEL_MAX + 1,
.min_uV = LM36274_VOLTAGE_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM36274_REG_VOUT_BOOST,
.vsel_mask = LM36274_VOUT_MASK,
},
{
.name = "ldo_vpos",
.of_match = "vpos",
.id = LM36274_LDO_POS,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM36274_LDO_VSEL_MAX + 1,
.min_uV = LM36274_VOLTAGE_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM36274_REG_VOUT_POS,
.vsel_mask = LM36274_VOUT_MASK,
.enable_reg = LM36274_REG_BIAS_CONFIG_1,
.enable_mask = LM36274_EN_VPOS_MASK,
},
{
.name = "ldo_vneg",
.of_match = "vneg",
.id = LM36274_LDO_NEG,
.ops = &lm363x_regulator_voltage_table_ops,
.n_voltages = LM36274_LDO_VSEL_MAX + 1,
.min_uV = LM36274_VOLTAGE_MIN,
.uV_step = LM363X_STEP_50mV,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.vsel_reg = LM36274_REG_VOUT_NEG,
.vsel_mask = LM36274_VOUT_MASK,
.enable_reg = LM36274_REG_BIAS_CONFIG_1,
.enable_mask = LM36274_EN_VNEG_MASK,
},
};
static struct gpio_desc *lm363x_regulator_of_get_enable_gpio(struct device *dev, int id)
{
/*
* Check LCM_EN1/2_GPIO is configured.
* Those pins are used for enabling VPOS/VNEG LDOs.
* Do not use devm* here: the regulator core takes over the
* lifecycle management of the GPIO descriptor.
*/
switch (id) {
case LM3632_LDO_POS:
case LM36274_LDO_POS:
return gpiod_get_index_optional(dev, "enable", 0,
GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
case LM3632_LDO_NEG:
case LM36274_LDO_NEG:
return gpiod_get_index_optional(dev, "enable", 1,
GPIOD_OUT_LOW | GPIOD_FLAGS_BIT_NONEXCLUSIVE);
default:
return NULL;
}
}
static int lm363x_regulator_set_ext_en(struct regmap *regmap, int id)
{
int ext_en_mask = 0;
switch (id) {
case LM3632_LDO_POS:
case LM3632_LDO_NEG:
ext_en_mask = LM3632_EXT_EN_MASK;
break;
case LM36274_LDO_POS:
case LM36274_LDO_NEG:
ext_en_mask = LM36274_EXT_EN_MASK;
break;
default:
return -ENODEV;
}
return regmap_update_bits(regmap, lm363x_regulator_desc[id].enable_reg,
ext_en_mask, ext_en_mask);
}
static int lm363x_regulator_probe(struct platform_device *pdev)
{
struct ti_lmu *lmu = dev_get_drvdata(pdev->dev.parent);
struct regmap *regmap = lmu->regmap;
struct regulator_config cfg = { };
struct regulator_dev *rdev;
struct device *dev = &pdev->dev;
int id = pdev->id;
struct gpio_desc *gpiod;
int ret;
cfg.dev = dev;
cfg.regmap = regmap;
/*
* LM3632 LDOs can be controlled by external pin.
* Register update is required if the pin is used.
*/
gpiod = lm363x_regulator_of_get_enable_gpio(dev, id);
if (IS_ERR(gpiod))
return PTR_ERR(gpiod);
if (gpiod) {
cfg.ena_gpiod = gpiod;
ret = lm363x_regulator_set_ext_en(regmap, id);
if (ret) {
gpiod_put(gpiod);
dev_err(dev, "External pin err: %d\n", ret);
return ret;
}
}
rdev = devm_regulator_register(dev, &lm363x_regulator_desc[id], &cfg);
if (IS_ERR(rdev)) {
ret = PTR_ERR(rdev);
dev_err(dev, "[%d] regulator register err: %d\n", id, ret);
return ret;
}
return 0;
}
static struct platform_driver lm363x_regulator_driver = {
.probe = lm363x_regulator_probe,
.driver = {
.name = "lm363x-regulator",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
};
module_platform_driver(lm363x_regulator_driver);
MODULE_DESCRIPTION("TI LM363X Regulator Driver");
MODULE_AUTHOR("Milo Kim");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:lm363x-regulator");