linux/drivers/regulator/tps65132-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

285 lines
7.7 KiB
C

/*
* TI TPS65132 Regulator driver
*
* Copyright (C) 2017 NVIDIA CORPORATION. All rights reserved.
*
* Author: Venkat Reddy Talla <vreddytalla@nvidia.com>
* Laxman Dewangan <ldewangan@nvidia.com>
*
* 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 "as is" WITHOUT ANY WARRANTY of any kind,
* whether express or implied; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*/
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
#define TPS65132_REG_VPOS 0x00
#define TPS65132_REG_VNEG 0x01
#define TPS65132_REG_APPS_DISP_DISN 0x03
#define TPS65132_REG_CONTROL 0x0FF
#define TPS65132_VOUT_MASK 0x1F
#define TPS65132_VOUT_N_VOLTAGE 0x15
#define TPS65132_VOUT_VMIN 4000000
#define TPS65132_VOUT_VMAX 6000000
#define TPS65132_VOUT_STEP 100000
#define TPS65132_REG_APPS_DIS_VPOS BIT(0)
#define TPS65132_REG_APPS_DIS_VNEG BIT(1)
#define TPS65132_REGULATOR_ID_VPOS 0
#define TPS65132_REGULATOR_ID_VNEG 1
#define TPS65132_MAX_REGULATORS 2
#define TPS65132_ACT_DIS_TIME_SLACK 1000
struct tps65132_reg_pdata {
struct gpio_desc *en_gpiod;
struct gpio_desc *act_dis_gpiod;
unsigned int act_dis_time_us;
int ena_gpio_state;
};
struct tps65132_regulator {
struct device *dev;
struct tps65132_reg_pdata reg_pdata[TPS65132_MAX_REGULATORS];
};
static int tps65132_regulator_enable(struct regulator_dev *rdev)
{
struct tps65132_regulator *tps = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev);
struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[id];
int ret;
if (!IS_ERR(rpdata->en_gpiod)) {
gpiod_set_value_cansleep(rpdata->en_gpiod, 1);
rpdata->ena_gpio_state = 1;
}
/* Hardware automatically enable discharge bit in enable */
if (rdev->constraints->active_discharge ==
REGULATOR_ACTIVE_DISCHARGE_DISABLE) {
ret = regulator_set_active_discharge_regmap(rdev, false);
if (ret < 0) {
dev_err(tps->dev, "Failed to disable active discharge: %d\n",
ret);
return ret;
}
}
return 0;
}
static int tps65132_regulator_disable(struct regulator_dev *rdev)
{
struct tps65132_regulator *tps = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev);
struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[id];
if (!IS_ERR(rpdata->en_gpiod)) {
gpiod_set_value_cansleep(rpdata->en_gpiod, 0);
rpdata->ena_gpio_state = 0;
}
if (!IS_ERR(rpdata->act_dis_gpiod)) {
gpiod_set_value_cansleep(rpdata->act_dis_gpiod, 1);
usleep_range(rpdata->act_dis_time_us, rpdata->act_dis_time_us +
TPS65132_ACT_DIS_TIME_SLACK);
gpiod_set_value_cansleep(rpdata->act_dis_gpiod, 0);
}
return 0;
}
static int tps65132_regulator_is_enabled(struct regulator_dev *rdev)
{
struct tps65132_regulator *tps = rdev_get_drvdata(rdev);
int id = rdev_get_id(rdev);
struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[id];
if (!IS_ERR(rpdata->en_gpiod))
return rpdata->ena_gpio_state;
return 1;
}
static const struct regulator_ops tps65132_regulator_ops = {
.enable = tps65132_regulator_enable,
.disable = tps65132_regulator_disable,
.is_enabled = tps65132_regulator_is_enabled,
.list_voltage = regulator_list_voltage_linear,
.map_voltage = regulator_map_voltage_linear,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.set_active_discharge = regulator_set_active_discharge_regmap,
};
static int tps65132_of_parse_cb(struct device_node *np,
const struct regulator_desc *desc,
struct regulator_config *config)
{
struct tps65132_regulator *tps = config->driver_data;
struct tps65132_reg_pdata *rpdata = &tps->reg_pdata[desc->id];
int ret;
rpdata->en_gpiod = devm_fwnode_gpiod_get(tps->dev, of_fwnode_handle(np),
"enable", GPIOD_ASIS,
"enable");
if (IS_ERR(rpdata->en_gpiod)) {
ret = PTR_ERR(rpdata->en_gpiod);
/* Ignore the error other than probe defer */
if (ret == -EPROBE_DEFER)
return ret;
return 0;
}
rpdata->act_dis_gpiod = devm_fwnode_gpiod_get(tps->dev,
of_fwnode_handle(np),
"active-discharge",
GPIOD_ASIS,
"active-discharge");
if (IS_ERR(rpdata->act_dis_gpiod)) {
ret = PTR_ERR(rpdata->act_dis_gpiod);
/* Ignore the error other than probe defer */
if (ret == -EPROBE_DEFER)
return ret;
return 0;
}
ret = of_property_read_u32(np, "ti,active-discharge-time-us",
&rpdata->act_dis_time_us);
if (ret < 0) {
dev_err(tps->dev, "Failed to read active discharge time:%d\n",
ret);
return ret;
}
return 0;
}
#define TPS65132_REGULATOR_DESC(_id, _name) \
[TPS65132_REGULATOR_ID_##_id] = { \
.name = "tps65132-"#_name, \
.supply_name = "vin", \
.id = TPS65132_REGULATOR_ID_##_id, \
.of_match = of_match_ptr(#_name), \
.of_parse_cb = tps65132_of_parse_cb, \
.ops = &tps65132_regulator_ops, \
.n_voltages = TPS65132_VOUT_N_VOLTAGE, \
.min_uV = TPS65132_VOUT_VMIN, \
.uV_step = TPS65132_VOUT_STEP, \
.enable_time = 500, \
.vsel_mask = TPS65132_VOUT_MASK, \
.vsel_reg = TPS65132_REG_##_id, \
.active_discharge_off = 0, \
.active_discharge_on = TPS65132_REG_APPS_DIS_##_id, \
.active_discharge_mask = TPS65132_REG_APPS_DIS_##_id, \
.active_discharge_reg = TPS65132_REG_APPS_DISP_DISN, \
.type = REGULATOR_VOLTAGE, \
.owner = THIS_MODULE, \
}
static const struct regulator_desc tps_regs_desc[TPS65132_MAX_REGULATORS] = {
TPS65132_REGULATOR_DESC(VPOS, outp),
TPS65132_REGULATOR_DESC(VNEG, outn),
};
static const struct regmap_range tps65132_no_reg_ranges[] = {
regmap_reg_range(TPS65132_REG_APPS_DISP_DISN + 1,
TPS65132_REG_CONTROL - 1),
};
static const struct regmap_access_table tps65132_no_reg_table = {
.no_ranges = tps65132_no_reg_ranges,
.n_no_ranges = ARRAY_SIZE(tps65132_no_reg_ranges),
};
static const struct regmap_config tps65132_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = TPS65132_REG_CONTROL,
.cache_type = REGCACHE_NONE,
.rd_table = &tps65132_no_reg_table,
.wr_table = &tps65132_no_reg_table,
};
static int tps65132_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct tps65132_regulator *tps;
struct regulator_dev *rdev;
struct regmap *rmap;
struct regulator_config config = { };
int id;
int ret;
tps = devm_kzalloc(dev, sizeof(*tps), GFP_KERNEL);
if (!tps)
return -ENOMEM;
rmap = devm_regmap_init_i2c(client, &tps65132_regmap_config);
if (IS_ERR(rmap)) {
ret = PTR_ERR(rmap);
dev_err(dev, "regmap init failed: %d\n", ret);
return ret;
}
i2c_set_clientdata(client, tps);
tps->dev = dev;
for (id = 0; id < TPS65132_MAX_REGULATORS; ++id) {
config.regmap = rmap;
config.dev = dev;
config.driver_data = tps;
rdev = devm_regulator_register(dev, &tps_regs_desc[id],
&config);
if (IS_ERR(rdev)) {
ret = PTR_ERR(rdev);
dev_err(dev, "regulator %s register failed: %d\n",
tps_regs_desc[id].name, ret);
return ret;
}
}
return 0;
}
static const struct i2c_device_id tps65132_id[] = {
{.name = "tps65132",},
{},
};
MODULE_DEVICE_TABLE(i2c, tps65132_id);
static struct i2c_driver tps65132_i2c_driver = {
.driver = {
.name = "tps65132",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe_new = tps65132_probe,
.id_table = tps65132_id,
};
module_i2c_driver(tps65132_i2c_driver);
MODULE_DESCRIPTION("tps65132 regulator driver");
MODULE_AUTHOR("Venkat Reddy Talla <vreddytalla@nvidia.com>");
MODULE_AUTHOR("Laxman Dewangan <ldewangan@nvidia.com>");
MODULE_LICENSE("GPL v2");