linux/drivers/regulator/as3711-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

267 lines
7.9 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* AS3711 PMIC regulator driver, using DCDC Step Down and LDO supplies
*
* Copyright (C) 2012 Renesas Electronics Corporation
* Author: Guennadi Liakhovetski, <g.liakhovetski@gmx.de>
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/mfd/as3711.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#include <linux/slab.h>
/*
* The regulator API supports 4 modes of operataion: FAST, NORMAL, IDLE and
* STANDBY. We map them in the following way to AS3711 SD1-4 DCDC modes:
* FAST: sdX_fast=1
* NORMAL: low_noise=1
* IDLE: low_noise=0
*/
static int as3711_set_mode_sd(struct regulator_dev *rdev, unsigned int mode)
{
unsigned int fast_bit = rdev->desc->enable_mask,
low_noise_bit = fast_bit << 4;
u8 val;
switch (mode) {
case REGULATOR_MODE_FAST:
val = fast_bit | low_noise_bit;
break;
case REGULATOR_MODE_NORMAL:
val = low_noise_bit;
break;
case REGULATOR_MODE_IDLE:
val = 0;
break;
default:
return -EINVAL;
}
return regmap_update_bits(rdev->regmap, AS3711_SD_CONTROL_1,
low_noise_bit | fast_bit, val);
}
static unsigned int as3711_get_mode_sd(struct regulator_dev *rdev)
{
unsigned int fast_bit = rdev->desc->enable_mask,
low_noise_bit = fast_bit << 4, mask = fast_bit | low_noise_bit;
unsigned int val;
int ret = regmap_read(rdev->regmap, AS3711_SD_CONTROL_1, &val);
if (ret < 0)
return ret;
if ((val & mask) == mask)
return REGULATOR_MODE_FAST;
if ((val & mask) == low_noise_bit)
return REGULATOR_MODE_NORMAL;
if (!(val & mask))
return REGULATOR_MODE_IDLE;
return -EINVAL;
}
static const struct regulator_ops as3711_sd_ops = {
.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,
.list_voltage = regulator_list_voltage_linear_range,
.map_voltage = regulator_map_voltage_linear_range,
.get_mode = as3711_get_mode_sd,
.set_mode = as3711_set_mode_sd,
};
static const struct regulator_ops as3711_aldo_ops = {
.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,
.list_voltage = regulator_list_voltage_linear_range,
.map_voltage = regulator_map_voltage_linear_range,
};
static const struct regulator_ops as3711_dldo_ops = {
.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,
.list_voltage = regulator_list_voltage_linear_range,
.map_voltage = regulator_map_voltage_linear_range,
};
static const struct linear_range as3711_sd_ranges[] = {
REGULATOR_LINEAR_RANGE(612500, 0x1, 0x40, 12500),
REGULATOR_LINEAR_RANGE(1425000, 0x41, 0x70, 25000),
REGULATOR_LINEAR_RANGE(2650000, 0x71, 0x7f, 50000),
};
static const struct linear_range as3711_aldo_ranges[] = {
REGULATOR_LINEAR_RANGE(1200000, 0, 0xf, 50000),
REGULATOR_LINEAR_RANGE(1800000, 0x10, 0x1f, 100000),
};
static const struct linear_range as3711_dldo_ranges[] = {
REGULATOR_LINEAR_RANGE(900000, 0, 0x10, 50000),
REGULATOR_LINEAR_RANGE(1750000, 0x20, 0x3f, 50000),
};
#define AS3711_REG(_id, _en_reg, _en_bit, _vmask, _sfx) \
[AS3711_REGULATOR_ ## _id] = { \
.name = "as3711-regulator-" # _id, \
.id = AS3711_REGULATOR_ ## _id, \
.n_voltages = (_vmask + 1), \
.ops = &as3711_ ## _sfx ## _ops, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
.vsel_reg = AS3711_ ## _id ## _VOLTAGE, \
.vsel_mask = _vmask, \
.enable_reg = AS3711_ ## _en_reg, \
.enable_mask = BIT(_en_bit), \
.linear_ranges = as3711_ ## _sfx ## _ranges, \
.n_linear_ranges = ARRAY_SIZE(as3711_ ## _sfx ## _ranges), \
}
static const struct regulator_desc as3711_reg_desc[] = {
AS3711_REG(SD_1, SD_CONTROL, 0, 0x7f, sd),
AS3711_REG(SD_2, SD_CONTROL, 1, 0x7f, sd),
AS3711_REG(SD_3, SD_CONTROL, 2, 0x7f, sd),
AS3711_REG(SD_4, SD_CONTROL, 3, 0x7f, sd),
AS3711_REG(LDO_1, LDO_1_VOLTAGE, 7, 0x1f, aldo),
AS3711_REG(LDO_2, LDO_2_VOLTAGE, 7, 0x1f, aldo),
AS3711_REG(LDO_3, LDO_3_VOLTAGE, 7, 0x3f, dldo),
AS3711_REG(LDO_4, LDO_4_VOLTAGE, 7, 0x3f, dldo),
AS3711_REG(LDO_5, LDO_5_VOLTAGE, 7, 0x3f, dldo),
AS3711_REG(LDO_6, LDO_6_VOLTAGE, 7, 0x3f, dldo),
AS3711_REG(LDO_7, LDO_7_VOLTAGE, 7, 0x3f, dldo),
AS3711_REG(LDO_8, LDO_8_VOLTAGE, 7, 0x3f, dldo),
/* StepUp output voltage depends on supplying regulator */
};
#define AS3711_REGULATOR_NUM ARRAY_SIZE(as3711_reg_desc)
static struct of_regulator_match
as3711_regulator_matches[AS3711_REGULATOR_NUM] = {
[AS3711_REGULATOR_SD_1] = { .name = "sd1" },
[AS3711_REGULATOR_SD_2] = { .name = "sd2" },
[AS3711_REGULATOR_SD_3] = { .name = "sd3" },
[AS3711_REGULATOR_SD_4] = { .name = "sd4" },
[AS3711_REGULATOR_LDO_1] = { .name = "ldo1" },
[AS3711_REGULATOR_LDO_2] = { .name = "ldo2" },
[AS3711_REGULATOR_LDO_3] = { .name = "ldo3" },
[AS3711_REGULATOR_LDO_4] = { .name = "ldo4" },
[AS3711_REGULATOR_LDO_5] = { .name = "ldo5" },
[AS3711_REGULATOR_LDO_6] = { .name = "ldo6" },
[AS3711_REGULATOR_LDO_7] = { .name = "ldo7" },
[AS3711_REGULATOR_LDO_8] = { .name = "ldo8" },
};
static int as3711_regulator_parse_dt(struct device *dev,
struct device_node **of_node, const int count)
{
struct as3711_regulator_pdata *pdata = dev_get_platdata(dev);
struct device_node *regulators =
of_get_child_by_name(dev->parent->of_node, "regulators");
struct of_regulator_match *match;
int ret, i;
if (!regulators) {
dev_err(dev, "regulator node not found\n");
return -ENODEV;
}
ret = of_regulator_match(dev->parent, regulators,
as3711_regulator_matches, count);
of_node_put(regulators);
if (ret < 0) {
dev_err(dev, "Error parsing regulator init data: %d\n", ret);
return ret;
}
for (i = 0, match = as3711_regulator_matches; i < count; i++, match++)
if (match->of_node) {
pdata->init_data[i] = match->init_data;
of_node[i] = match->of_node;
}
return 0;
}
static int as3711_regulator_probe(struct platform_device *pdev)
{
struct as3711_regulator_pdata *pdata = dev_get_platdata(&pdev->dev);
struct as3711 *as3711 = dev_get_drvdata(pdev->dev.parent);
struct regulator_config config = {.dev = &pdev->dev,};
struct device_node *of_node[AS3711_REGULATOR_NUM] = {};
struct regulator_dev *rdev;
int ret;
int id;
if (!pdata) {
dev_err(&pdev->dev, "No platform data...\n");
return -ENODEV;
}
if (pdev->dev.parent->of_node) {
ret = as3711_regulator_parse_dt(&pdev->dev, of_node, AS3711_REGULATOR_NUM);
if (ret < 0) {
dev_err(&pdev->dev, "DT parsing failed: %d\n", ret);
return ret;
}
}
for (id = 0; id < AS3711_REGULATOR_NUM; id++) {
config.init_data = pdata->init_data[id];
config.regmap = as3711->regmap;
config.of_node = of_node[id];
rdev = devm_regulator_register(&pdev->dev, &as3711_reg_desc[id],
&config);
if (IS_ERR(rdev)) {
dev_err(&pdev->dev, "Failed to register regulator %s\n",
as3711_reg_desc[id].name);
return PTR_ERR(rdev);
}
}
return 0;
}
static struct platform_driver as3711_regulator_driver = {
.driver = {
.name = "as3711-regulator",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe = as3711_regulator_probe,
};
static int __init as3711_regulator_init(void)
{
return platform_driver_register(&as3711_regulator_driver);
}
subsys_initcall(as3711_regulator_init);
static void __exit as3711_regulator_exit(void)
{
platform_driver_unregister(&as3711_regulator_driver);
}
module_exit(as3711_regulator_exit);
MODULE_AUTHOR("Guennadi Liakhovetski <g.liakhovetski@gmx.de>");
MODULE_DESCRIPTION("AS3711 regulator driver");
MODULE_ALIAS("platform:as3711-regulator");
MODULE_LICENSE("GPL v2");