linux/drivers/regulator/max77693-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

306 lines
8.6 KiB
C

// SPDX-License-Identifier: GPL-2.0+
//
// max77693.c - Regulator driver for the Maxim 77693 and 77843
//
// Copyright (C) 2013-2015 Samsung Electronics
// Jonghwa Lee <jonghwa3.lee@samsung.com>
// Krzysztof Kozlowski <krzk@kernel.org>
//
// This driver is based on max77686.c
#include <linux/err.h>
#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/export.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/mfd/max77693.h>
#include <linux/mfd/max77693-common.h>
#include <linux/mfd/max77693-private.h>
#include <linux/mfd/max77843-private.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regmap.h>
/*
* ID for MAX77843 regulators.
* There is no need for such for MAX77693.
*/
enum max77843_regulator_type {
MAX77843_SAFEOUT1 = 0,
MAX77843_SAFEOUT2,
MAX77843_CHARGER,
MAX77843_NUM,
};
/* Register differences between chargers: MAX77693 and MAX77843 */
struct chg_reg_data {
unsigned int linear_reg;
unsigned int linear_mask;
unsigned int uA_step;
unsigned int min_sel;
};
/*
* MAX77693 CHARGER regulator - Min : 20mA, Max : 2580mA, step : 20mA
* 0x00, 0x01, 0x2, 0x03 = 60 mA
* 0x04 ~ 0x7E = (60 + (X - 3) * 20) mA
* Actually for MAX77693 the driver manipulates the maximum input current,
* not the fast charge current (output). This should be fixed.
*
* On MAX77843 the calculation formula is the same (except values).
* Fortunately it properly manipulates the fast charge current.
*/
static int max77693_chg_get_current_limit(struct regulator_dev *rdev)
{
const struct chg_reg_data *reg_data = rdev_get_drvdata(rdev);
unsigned int chg_min_uA = rdev->constraints->min_uA;
unsigned int chg_max_uA = rdev->constraints->max_uA;
unsigned int reg, sel;
unsigned int val;
int ret;
ret = regmap_read(rdev->regmap, reg_data->linear_reg, &reg);
if (ret < 0)
return ret;
sel = reg & reg_data->linear_mask;
/* the first four codes for charger current are all 60mA */
if (sel <= reg_data->min_sel)
sel = 0;
else
sel -= reg_data->min_sel;
val = chg_min_uA + reg_data->uA_step * sel;
if (val > chg_max_uA)
return -EINVAL;
return val;
}
static int max77693_chg_set_current_limit(struct regulator_dev *rdev,
int min_uA, int max_uA)
{
const struct chg_reg_data *reg_data = rdev_get_drvdata(rdev);
unsigned int chg_min_uA = rdev->constraints->min_uA;
int sel = 0;
while (chg_min_uA + reg_data->uA_step * sel < min_uA)
sel++;
if (chg_min_uA + reg_data->uA_step * sel > max_uA)
return -EINVAL;
/* the first four codes for charger current are all 60mA */
sel += reg_data->min_sel;
return regmap_write(rdev->regmap, reg_data->linear_reg, sel);
}
/* end of CHARGER regulator ops */
/* Returns regmap suitable for given regulator on chosen device */
static struct regmap *max77693_get_regmap(enum max77693_types type,
struct max77693_dev *max77693,
int reg_id)
{
if (type == TYPE_MAX77693)
return max77693->regmap;
/* Else: TYPE_MAX77843 */
switch (reg_id) {
case MAX77843_SAFEOUT1:
case MAX77843_SAFEOUT2:
return max77693->regmap;
case MAX77843_CHARGER:
return max77693->regmap_chg;
default:
return max77693->regmap;
}
}
static const unsigned int max77693_safeout_table[] = {
4850000,
4900000,
4950000,
3300000,
};
static const struct regulator_ops max77693_safeout_ops = {
.list_voltage = regulator_list_voltage_table,
.is_enabled = regulator_is_enabled_regmap,
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
};
static const struct regulator_ops max77693_charger_ops = {
.is_enabled = regulator_is_enabled_regmap,
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.get_current_limit = max77693_chg_get_current_limit,
.set_current_limit = max77693_chg_set_current_limit,
};
#define max77693_regulator_desc_esafeout(_num) { \
.name = "ESAFEOUT"#_num, \
.id = MAX77693_ESAFEOUT##_num, \
.of_match = of_match_ptr("ESAFEOUT"#_num), \
.regulators_node = of_match_ptr("regulators"), \
.n_voltages = 4, \
.ops = &max77693_safeout_ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
.volt_table = max77693_safeout_table, \
.vsel_reg = MAX77693_CHG_REG_SAFEOUT_CTRL, \
.vsel_mask = SAFEOUT_CTRL_SAFEOUT##_num##_MASK, \
.enable_reg = MAX77693_CHG_REG_SAFEOUT_CTRL, \
.enable_mask = SAFEOUT_CTRL_ENSAFEOUT##_num##_MASK , \
}
static const struct regulator_desc max77693_supported_regulators[] = {
max77693_regulator_desc_esafeout(1),
max77693_regulator_desc_esafeout(2),
{
.name = "CHARGER",
.id = MAX77693_CHARGER,
.of_match = of_match_ptr("CHARGER"),
.regulators_node = of_match_ptr("regulators"),
.ops = &max77693_charger_ops,
.type = REGULATOR_CURRENT,
.owner = THIS_MODULE,
.enable_reg = MAX77693_CHG_REG_CHG_CNFG_00,
.enable_mask = CHG_CNFG_00_CHG_MASK |
CHG_CNFG_00_BUCK_MASK,
.enable_val = CHG_CNFG_00_CHG_MASK | CHG_CNFG_00_BUCK_MASK,
},
};
static const struct chg_reg_data max77693_chg_reg_data = {
.linear_reg = MAX77693_CHG_REG_CHG_CNFG_09,
.linear_mask = CHG_CNFG_09_CHGIN_ILIM_MASK,
.uA_step = 20000,
.min_sel = 3,
};
#define max77843_regulator_desc_esafeout(num) { \
.name = "SAFEOUT" # num, \
.id = MAX77843_SAFEOUT ## num, \
.ops = &max77693_safeout_ops, \
.of_match = of_match_ptr("SAFEOUT" # num), \
.regulators_node = of_match_ptr("regulators"), \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
.n_voltages = ARRAY_SIZE(max77693_safeout_table), \
.volt_table = max77693_safeout_table, \
.enable_reg = MAX77843_SYS_REG_SAFEOUTCTRL, \
.enable_mask = MAX77843_REG_SAFEOUTCTRL_ENSAFEOUT ## num, \
.vsel_reg = MAX77843_SYS_REG_SAFEOUTCTRL, \
.vsel_mask = MAX77843_REG_SAFEOUTCTRL_SAFEOUT ## num ## _MASK, \
}
static const struct regulator_desc max77843_supported_regulators[] = {
[MAX77843_SAFEOUT1] = max77843_regulator_desc_esafeout(1),
[MAX77843_SAFEOUT2] = max77843_regulator_desc_esafeout(2),
[MAX77843_CHARGER] = {
.name = "CHARGER",
.id = MAX77843_CHARGER,
.ops = &max77693_charger_ops,
.of_match = of_match_ptr("CHARGER"),
.regulators_node = of_match_ptr("regulators"),
.type = REGULATOR_CURRENT,
.owner = THIS_MODULE,
.enable_reg = MAX77843_CHG_REG_CHG_CNFG_00,
.enable_mask = MAX77843_CHG_MASK,
.enable_val = MAX77843_CHG_MASK,
},
};
static const struct chg_reg_data max77843_chg_reg_data = {
.linear_reg = MAX77843_CHG_REG_CHG_CNFG_02,
.linear_mask = MAX77843_CHG_FAST_CHG_CURRENT_MASK,
.uA_step = MAX77843_CHG_FAST_CHG_CURRENT_STEP,
.min_sel = 2,
};
static int max77693_pmic_probe(struct platform_device *pdev)
{
enum max77693_types type = platform_get_device_id(pdev)->driver_data;
struct max77693_dev *iodev = dev_get_drvdata(pdev->dev.parent);
const struct regulator_desc *regulators;
unsigned int regulators_size;
int i;
struct regulator_config config = { };
config.dev = iodev->dev;
switch (type) {
case TYPE_MAX77693:
regulators = max77693_supported_regulators;
regulators_size = ARRAY_SIZE(max77693_supported_regulators);
config.driver_data = (void *)&max77693_chg_reg_data;
break;
case TYPE_MAX77843:
regulators = max77843_supported_regulators;
regulators_size = ARRAY_SIZE(max77843_supported_regulators);
config.driver_data = (void *)&max77843_chg_reg_data;
break;
default:
dev_err(&pdev->dev, "Unsupported device type: %u\n", type);
return -ENODEV;
}
for (i = 0; i < regulators_size; i++) {
struct regulator_dev *rdev;
config.regmap = max77693_get_regmap(type, iodev,
regulators[i].id);
rdev = devm_regulator_register(&pdev->dev,
&regulators[i], &config);
if (IS_ERR(rdev)) {
dev_err(&pdev->dev,
"Failed to initialize regulator-%d\n", i);
return PTR_ERR(rdev);
}
}
return 0;
}
static const struct platform_device_id max77693_pmic_id[] = {
{ "max77693-pmic", TYPE_MAX77693 },
{ "max77843-regulator", TYPE_MAX77843 },
{},
};
MODULE_DEVICE_TABLE(platform, max77693_pmic_id);
static struct platform_driver max77693_pmic_driver = {
.driver = {
.name = "max77693-pmic",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe = max77693_pmic_probe,
.id_table = max77693_pmic_id,
};
static int __init max77693_pmic_init(void)
{
return platform_driver_register(&max77693_pmic_driver);
}
subsys_initcall(max77693_pmic_init);
static void __exit max77693_pmic_cleanup(void)
{
platform_driver_unregister(&max77693_pmic_driver);
}
module_exit(max77693_pmic_cleanup);
MODULE_DESCRIPTION("MAXIM 77693/77843 regulator driver");
MODULE_AUTHOR("Jonghwa Lee <jonghwa3.lee@samsung.com>");
MODULE_AUTHOR("Krzysztof Kozlowski <krzk@kernel.org>");
MODULE_LICENSE("GPL");