linux/drivers/regulator/hi6421v530-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

212 lines
5.8 KiB
C

// SPDX-License-Identifier: GPL-2.0
//
// Device driver for regulators in Hi6421V530 IC
//
// Copyright (c) <2017> HiSilicon Technologies Co., Ltd.
// http://www.hisilicon.com
// Copyright (c) <2017> Linaro Ltd.
// https://www.linaro.org
//
// Author: Wang Xiaoyin <hw.wangxiaoyin@hisilicon.com>
// Guodong Xu <guodong.xu@linaro.org>
#include <linux/mfd/hi6421-pmic.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/regulator/driver.h>
/*
* struct hi6421v530_regulator_info - hi6421v530 regulator information
* @desc: regulator description
* @mode_mask: ECO mode bitmask of LDOs; for BUCKs, this masks sleep
* @eco_microamp: eco mode load upper limit (in uA), valid for LDOs only
*/
struct hi6421v530_regulator_info {
struct regulator_desc rdesc;
u8 mode_mask;
u32 eco_microamp;
};
/* HI6421v530 regulators */
enum hi6421v530_regulator_id {
HI6421V530_LDO3,
HI6421V530_LDO9,
HI6421V530_LDO11,
HI6421V530_LDO15,
HI6421V530_LDO16,
};
static const unsigned int ldo_3_voltages[] = {
1800000, 1825000, 1850000, 1875000,
1900000, 1925000, 1950000, 1975000,
2000000, 2025000, 2050000, 2075000,
2100000, 2125000, 2150000, 2200000,
};
static const unsigned int ldo_9_11_voltages[] = {
1750000, 1800000, 1825000, 2800000,
2850000, 2950000, 3000000, 3300000,
};
static const unsigned int ldo_15_16_voltages[] = {
1750000, 1800000, 2400000, 2600000,
2700000, 2850000, 2950000, 3000000,
};
static const struct regulator_ops hi6421v530_ldo_ops;
#define HI6421V530_LDO_ENABLE_TIME (350)
/*
* _id - LDO id name string
* v_table - voltage table
* vreg - voltage select register
* vmask - voltage select mask
* ereg - enable register
* emask - enable mask
* odelay - off/on delay time in uS
* ecomask - eco mode mask
* ecoamp - eco mode load uppler limit in uA
*/
#define HI6421V530_LDO(_ID, v_table, vreg, vmask, ereg, emask, \
odelay, ecomask, ecoamp) { \
.rdesc = { \
.name = #_ID, \
.of_match = of_match_ptr(#_ID), \
.regulators_node = of_match_ptr("regulators"), \
.ops = &hi6421v530_ldo_ops, \
.type = REGULATOR_VOLTAGE, \
.id = HI6421V530_##_ID, \
.owner = THIS_MODULE, \
.n_voltages = ARRAY_SIZE(v_table), \
.volt_table = v_table, \
.vsel_reg = HI6421_REG_TO_BUS_ADDR(vreg), \
.vsel_mask = vmask, \
.enable_reg = HI6421_REG_TO_BUS_ADDR(ereg), \
.enable_mask = emask, \
.enable_time = HI6421V530_LDO_ENABLE_TIME, \
.off_on_delay = odelay, \
}, \
.mode_mask = ecomask, \
.eco_microamp = ecoamp, \
}
/* HI6421V530 regulator information */
static struct hi6421v530_regulator_info hi6421v530_regulator_info[] = {
HI6421V530_LDO(LDO3, ldo_3_voltages, 0x061, 0xf, 0x060, 0x2,
20000, 0x6, 8000),
HI6421V530_LDO(LDO9, ldo_9_11_voltages, 0x06b, 0x7, 0x06a, 0x2,
40000, 0x6, 8000),
HI6421V530_LDO(LDO11, ldo_9_11_voltages, 0x06f, 0x7, 0x06e, 0x2,
40000, 0x6, 8000),
HI6421V530_LDO(LDO15, ldo_15_16_voltages, 0x077, 0x7, 0x076, 0x2,
40000, 0x6, 8000),
HI6421V530_LDO(LDO16, ldo_15_16_voltages, 0x079, 0x7, 0x078, 0x2,
40000, 0x6, 8000),
};
static unsigned int hi6421v530_regulator_ldo_get_mode(
struct regulator_dev *rdev)
{
struct hi6421v530_regulator_info *info;
unsigned int reg_val;
info = rdev_get_drvdata(rdev);
regmap_read(rdev->regmap, rdev->desc->enable_reg, &reg_val);
if (reg_val & (info->mode_mask))
return REGULATOR_MODE_IDLE;
return REGULATOR_MODE_NORMAL;
}
static int hi6421v530_regulator_ldo_set_mode(struct regulator_dev *rdev,
unsigned int mode)
{
struct hi6421v530_regulator_info *info;
unsigned int new_mode;
info = rdev_get_drvdata(rdev);
switch (mode) {
case REGULATOR_MODE_NORMAL:
new_mode = 0;
break;
case REGULATOR_MODE_IDLE:
new_mode = info->mode_mask;
break;
default:
return -EINVAL;
}
regmap_update_bits(rdev->regmap, rdev->desc->enable_reg,
info->mode_mask, new_mode);
return 0;
}
static const struct regulator_ops hi6421v530_ldo_ops = {
.is_enabled = regulator_is_enabled_regmap,
.enable = regulator_enable_regmap,
.disable = regulator_disable_regmap,
.list_voltage = regulator_list_voltage_table,
.map_voltage = regulator_map_voltage_ascend,
.get_voltage_sel = regulator_get_voltage_sel_regmap,
.set_voltage_sel = regulator_set_voltage_sel_regmap,
.get_mode = hi6421v530_regulator_ldo_get_mode,
.set_mode = hi6421v530_regulator_ldo_set_mode,
};
static int hi6421v530_regulator_probe(struct platform_device *pdev)
{
struct hi6421_pmic *pmic;
struct regulator_dev *rdev;
struct regulator_config config = { };
unsigned int i;
pmic = dev_get_drvdata(pdev->dev.parent);
if (!pmic) {
dev_err(&pdev->dev, "no pmic in the regulator parent node\n");
return -ENODEV;
}
for (i = 0; i < ARRAY_SIZE(hi6421v530_regulator_info); i++) {
config.dev = pdev->dev.parent;
config.regmap = pmic->regmap;
config.driver_data = &hi6421v530_regulator_info[i];
rdev = devm_regulator_register(&pdev->dev,
&hi6421v530_regulator_info[i].rdesc,
&config);
if (IS_ERR(rdev)) {
dev_err(&pdev->dev, "failed to register regulator %s\n",
hi6421v530_regulator_info[i].rdesc.name);
return PTR_ERR(rdev);
}
}
return 0;
}
static const struct platform_device_id hi6421v530_regulator_table[] = {
{ .name = "hi6421v530-regulator" },
{},
};
MODULE_DEVICE_TABLE(platform, hi6421v530_regulator_table);
static struct platform_driver hi6421v530_regulator_driver = {
.id_table = hi6421v530_regulator_table,
.driver = {
.name = "hi6421v530-regulator",
.probe_type = PROBE_PREFER_ASYNCHRONOUS,
},
.probe = hi6421v530_regulator_probe,
};
module_platform_driver(hi6421v530_regulator_driver);
MODULE_AUTHOR("Wang Xiaoyin <hw.wangxiaoyin@hisilicon.com>");
MODULE_DESCRIPTION("Hi6421v530 regulator driver");
MODULE_LICENSE("GPL v2");