linux-stable/drivers/regulator/mt6311-regulator.c

165 lines
4.1 KiB
C
Raw Normal View History

// SPDX-License-Identifier: GPL-2.0
//
// Copyright (c) 2015 MediaTek Inc.
// Author: Henry Chen <henryc.chen@mediatek.com>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/of_regulator.h>
#include <linux/regulator/mt6311.h>
#include <linux/slab.h>
#include "mt6311-regulator.h"
static const struct regmap_config mt6311_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = MT6311_FQMTR_CON4,
.cache_type = REGCACHE_RBTREE,
};
/* Default limits measured in millivolts and milliamps */
#define MT6311_MIN_UV 600000
#define MT6311_MAX_UV 1393750
#define MT6311_STEP_UV 6250
static const struct regulator_ops mt6311_buck_ops = {
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_time_sel = regulator_set_voltage_time_sel,
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
};
static const struct regulator_ops mt6311_ldo_ops = {
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.is_enabled = regulator_is_enabled_regmap,
};
#define MT6311_BUCK(_id) \
{\
.name = #_id,\
.ops = &mt6311_buck_ops,\
.of_match = of_match_ptr(#_id),\
.regulators_node = of_match_ptr("regulators"),\
.type = REGULATOR_VOLTAGE,\
.id = MT6311_ID_##_id,\
.n_voltages = (MT6311_MAX_UV - MT6311_MIN_UV) / MT6311_STEP_UV + 1,\
.min_uV = MT6311_MIN_UV,\
.uV_step = MT6311_STEP_UV,\
.owner = THIS_MODULE,\
.enable_reg = MT6311_VDVFS11_CON9,\
.enable_mask = MT6311_PMIC_VDVFS11_EN_MASK,\
.vsel_reg = MT6311_VDVFS11_CON12,\
.vsel_mask = MT6311_PMIC_VDVFS11_VOSEL_MASK,\
}
#define MT6311_LDO(_id) \
{\
.name = #_id,\
.ops = &mt6311_ldo_ops,\
.of_match = of_match_ptr(#_id),\
.regulators_node = of_match_ptr("regulators"),\
.type = REGULATOR_VOLTAGE,\
.id = MT6311_ID_##_id,\
.owner = THIS_MODULE,\
.enable_reg = MT6311_LDO_CON3,\
.enable_mask = MT6311_PMIC_RG_VBIASN_EN_MASK,\
}
static const struct regulator_desc mt6311_regulators[] = {
MT6311_BUCK(VDVFS),
MT6311_LDO(VBIASN),
};
/*
* I2C driver interface functions
*/
static int mt6311_i2c_probe(struct i2c_client *i2c)
{
struct regulator_config config = { };
struct regulator_dev *rdev;
struct regmap *regmap;
int i, ret;
unsigned int data;
regmap = devm_regmap_init_i2c(i2c, &mt6311_regmap_config);
if (IS_ERR(regmap)) {
ret = PTR_ERR(regmap);
dev_err(&i2c->dev, "Failed to allocate register map: %d\n",
ret);
return ret;
}
ret = regmap_read(regmap, MT6311_SWCID, &data);
if (ret < 0) {
dev_err(&i2c->dev, "Failed to read DEVICE_ID reg: %d\n", ret);
return ret;
}
switch (data) {
case MT6311_E1_CID_CODE:
case MT6311_E2_CID_CODE:
case MT6311_E3_CID_CODE:
break;
default:
dev_err(&i2c->dev, "Unsupported device id = 0x%x.\n", data);
return -ENODEV;
}
for (i = 0; i < MT6311_MAX_REGULATORS; i++) {
config.dev = &i2c->dev;
config.regmap = regmap;
rdev = devm_regulator_register(&i2c->dev,
&mt6311_regulators[i], &config);
if (IS_ERR(rdev)) {
dev_err(&i2c->dev,
"Failed to register MT6311 regulator\n");
return PTR_ERR(rdev);
}
}
return 0;
}
static const struct i2c_device_id mt6311_i2c_id[] = {
{"mt6311", 0},
{},
};
MODULE_DEVICE_TABLE(i2c, mt6311_i2c_id);
#ifdef CONFIG_OF
static const struct of_device_id mt6311_dt_ids[] = {
{ .compatible = "mediatek,mt6311-regulator",
.data = &mt6311_i2c_id[0] },
{},
};
MODULE_DEVICE_TABLE(of, mt6311_dt_ids);
#endif
static struct i2c_driver mt6311_regulator_driver = {
.driver = {
.name = "mt6311",
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>
2023-03-16 19:54:38 +00:00
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
.of_match_table = of_match_ptr(mt6311_dt_ids),
},
.probe = mt6311_i2c_probe,
.id_table = mt6311_i2c_id,
};
module_i2c_driver(mt6311_regulator_driver);
MODULE_AUTHOR("Henry Chen <henryc.chen@mediatek.com>");
MODULE_DESCRIPTION("Regulator device driver for Mediatek MT6311");
MODULE_LICENSE("GPL v2");