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rM2: regulator: Copy the rM2 sy7636a-regulator driver

Copy the rM2 zero-sugar branch
(https://github.com/reMarkable/linux/tree/zero-sugar) to the new kernel.

Signed-off-by: Alistair Francis <alistair@alistair23.me>
5.4-rM2-2.2.x-imx-deep-sleep
Alistair Francis 2021-02-07 09:49:42 -08:00
parent 63323d8556
commit 9592b400b2
3 changed files with 240 additions and 0 deletions

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@ -890,6 +890,12 @@ config REGULATOR_STM32_BOOSTER
This driver can also be built as a module. If so, the module
will be called stm32-booster.
config REGULATOR_SY7636A
tristate "Silergy SY7636A voltage regulator"
depends on MFD_SY7636A
help
This driver supports Silergy SY3686A voltage regulator.
config REGULATOR_STM32_VREFBUF
tristate "STMicroelectronics STM32 VREFBUF"
depends on ARCH_STM32 || COMPILE_TEST

View File

@ -112,6 +112,7 @@ obj-$(CONFIG_REGULATOR_SC2731) += sc2731-regulator.o
obj-$(CONFIG_REGULATOR_SKY81452) += sky81452-regulator.o
obj-$(CONFIG_REGULATOR_SLG51000) += slg51000-regulator.o
obj-$(CONFIG_REGULATOR_STM32_BOOSTER) += stm32-booster.o
obj-$(CONFIG_REGULATOR_SY7636A) += sy7636a-regulator.o
obj-$(CONFIG_REGULATOR_STM32_VREFBUF) += stm32-vrefbuf.o
obj-$(CONFIG_REGULATOR_STM32_PWR) += stm32-pwr.o
obj-$(CONFIG_REGULATOR_STPMIC1) += stpmic1_regulator.o

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@ -0,0 +1,233 @@
/*
* Functions to access SY3686A power management chip voltages
*
* Copyright (C) 2019 reMarkable AS - http://www.remarkable.com/
*
* Author: Lars Ivar Miljeteig <lars.ivar.miljeteig@remarkable.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 version 2.
*
* 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/module.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/gpio/consumer.h>
#include <linux/mfd/sy7636a.h>
static int get_vcom_voltage_op(struct regulator_dev *rdev)
{
int ret;
ret = get_vcom_voltage_mv(rdev->regmap);
if (ret < 0)
return ret;
return ret * 1000;
}
static int disable_regulator(struct regulator_dev *rdev)
{
struct sy7636a *sy7636a = dev_get_drvdata(rdev->dev.parent);
int ret = 0;
mutex_lock(&sy7636a->reglock);
ret = regulator_disable_regmap(rdev);
usleep_range(30000, 35000);
mutex_unlock(&sy7636a->reglock);
return ret;
}
static int sy7636a_regulator_is_enabled(struct regulator_dev *rdev)
{
struct sy7636a *sy7636a = dev_get_drvdata(rdev->dev.parent);
int ret;
mutex_lock(&sy7636a->reglock);
ret = regulator_is_enabled_regmap(rdev);
mutex_unlock(&sy7636a->reglock);
return ret;
}
static int enable_regulator_pgood(struct regulator_dev *rdev)
{
struct sy7636a *sy7636a = dev_get_drvdata(rdev->dev.parent);
int pwr_good = 0;
int ret = 0;
unsigned long t0, t1;
const unsigned int wait_time = 500;
unsigned int wait_cnt;
t0 = jiffies;
mutex_lock(&sy7636a->reglock);
ret = regulator_enable_regmap(rdev);
if (ret) {
goto finish;
}
for (wait_cnt = 0; wait_cnt < wait_time; wait_cnt++) {
pwr_good = gpiod_get_value_cansleep(sy7636a->pgood_gpio);
if (pwr_good < 0) {
dev_err(&rdev->dev, "Failed to read pgood gpio: %d\n", pwr_good);
ret = pwr_good;
goto finish;
}
else if (pwr_good)
break;
usleep_range(1000, 1500);
}
t1 = jiffies;
if (!pwr_good) {
dev_err(&rdev->dev, "Power good signal timeout after %u ms\n",
jiffies_to_msecs(t1 - t0));
ret = -ETIME;
goto finish;
}
dev_dbg(&rdev->dev, "Power good OK (took %u ms, %u waits)\n",
jiffies_to_msecs(t1 - t0),
wait_cnt);
finish:
mutex_unlock(&sy7636a->reglock);
return ret;
}
static const struct regulator_ops sy7636a_vcom_volt_ops = {
.get_voltage = get_vcom_voltage_op,
.enable = enable_regulator_pgood,
.disable = disable_regulator,
.is_enabled = sy7636a_regulator_is_enabled,
};
struct regulator_desc desc = {
.name = "vcom",
.id = 0,
.ops = &sy7636a_vcom_volt_ops,
.type = REGULATOR_VOLTAGE,
.owner = THIS_MODULE,
.enable_reg = SY7636A_REG_OPERATION_MODE_CRL,
.enable_mask = SY7636A_OPERATION_MODE_CRL_ONOFF,
.regulators_node = of_match_ptr("regulators"),
.of_match = of_match_ptr("vcom"),
};
static int sy7636a_regulator_init(struct sy7636a *sy7636a)
{
return regmap_write(sy7636a->regmap,
SY7636A_REG_POWER_ON_DELAY_TIME,
0x0);
}
static int sy7636a_regulator_suspend(struct device *dev)
{
int ret;
struct sy7636a *sy7636a = dev_get_drvdata(dev->parent);
ret = get_vcom_voltage_mv(sy7636a->regmap);
if (ret > 0)
sy7636a->vcom = (unsigned int)ret;
return 0;
}
static int sy7636a_regulator_resume(struct device *dev)
{
int ret;
struct sy7636a *sy7636a = dev_get_drvdata(dev->parent);
if (!sy7636a->vcom || sy7636a->vcom > 5000) {
dev_warn(dev, "Vcom value invalid, and thus not restored\n");
}
else {
ret = set_vcom_voltage_mv(sy7636a->regmap, sy7636a->vcom);
if (ret)
return ret;
}
return sy7636a_regulator_init(sy7636a);
}
static int sy7636a_regulator_probe(struct platform_device *pdev)
{
struct sy7636a *sy7636a = dev_get_drvdata(pdev->dev.parent);
struct regulator_config config = { };
struct regulator_dev *rdev;
struct gpio_desc *gdp;
int ret;
if (!sy7636a)
return -EPROBE_DEFER;
platform_set_drvdata(pdev, sy7636a);
mutex_init(&sy7636a->reglock);
gdp = devm_gpiod_get(sy7636a->dev, "epd-pwr-good", GPIOD_IN);
if (IS_ERR(gdp)) {
dev_err(sy7636a->dev, "Power good GPIO fault %ld\n", PTR_ERR(gdp));
return PTR_ERR(gdp);
}
sy7636a->pgood_gpio = gdp;
dev_info(sy7636a->dev,
"Power good GPIO registered (gpio# %d)\n",
desc_to_gpio(sy7636a->pgood_gpio));
ret = sy7636a_regulator_init(sy7636a);
if (ret) {
dev_err(sy7636a->dev, "Failed to initialize regulator: %d\n", ret);
return ret;
}
config.dev = &pdev->dev;
config.dev->of_node = sy7636a->dev->of_node;
config.driver_data = sy7636a;
config.regmap = sy7636a->regmap;
rdev = devm_regulator_register(&pdev->dev, &desc, &config);
if (IS_ERR(rdev)) {
dev_err(sy7636a->dev, "Failed to register %s regulator\n",
pdev->name);
return PTR_ERR(rdev);
}
return 0;
}
static const struct platform_device_id sy7636a_regulator_id_table[] = {
{ "sy7636a-regulator", },
};
MODULE_DEVICE_TABLE(platform, sy7636a_regulator_id_table);
static const struct dev_pm_ops sy7636a_pm_ops = {
.suspend = sy7636a_regulator_suspend,
.resume = sy7636a_regulator_resume,
};
static struct platform_driver sy7636a_regulator_driver = {
.driver = {
.name = "sy7636a-regulator",
.pm = &sy7636a_pm_ops,
},
.probe = sy7636a_regulator_probe,
.id_table = sy7636a_regulator_id_table,
};
module_platform_driver(sy7636a_regulator_driver);
MODULE_AUTHOR("Lars Ivar Miljeteig <lars.ivar.miljeteig@remarkable.com>");
MODULE_DESCRIPTION("SY7636A voltage regulator driver");
MODULE_LICENSE("GPL v2");