Initial support for the Silergy SY7636A-regulator Power Management chip driver. Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx> --- drivers/regulator/Kconfig | 6 + drivers/regulator/Makefile | 1 + drivers/regulator/sy7636a-regulator.c | 233 ++++++++++++++++++++++++++ 3 files changed, 240 insertions(+) create mode 100644 drivers/regulator/sy7636a-regulator.c diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 5abdd29fb9f3..76510a0db4f9 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -1097,6 +1097,12 @@ config REGULATOR_STW481X_VMMC This driver supports the internal VMMC regulator in the STw481x PMIC chips. +config REGULATOR_SY7636A + tristate "Silergy SY7636A voltage regulator" + depends on MFD_SY7636A + help + This driver supports Silergy SY3686A voltage regulator. + config REGULATOR_SY8106A tristate "Silergy SY8106A regulator" depends on I2C && (OF || COMPILE_TEST) diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index 680e539f6579..fe05347cbf84 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -131,6 +131,7 @@ obj-$(CONFIG_REGULATOR_STM32_VREFBUF) += stm32-vrefbuf.o obj-$(CONFIG_REGULATOR_STM32_PWR) += stm32-pwr.o obj-$(CONFIG_REGULATOR_STPMIC1) += stpmic1_regulator.o obj-$(CONFIG_REGULATOR_STW481X_VMMC) += stw481x-vmmc.o +obj-$(CONFIG_REGULATOR_SY7636A) += sy7636a-regulator.o obj-$(CONFIG_REGULATOR_SY8106A) += sy8106a-regulator.o obj-$(CONFIG_REGULATOR_SY8824X) += sy8824x.o obj-$(CONFIG_REGULATOR_SY8827N) += sy8827n.o diff --git a/drivers/regulator/sy7636a-regulator.c b/drivers/regulator/sy7636a-regulator.c new file mode 100644 index 000000000000..a639830298d6 --- /dev/null +++ b/drivers/regulator/sy7636a-regulator.c @@ -0,0 +1,233 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Functions to access SY3686A power management chip voltages + * + * Copyright (C) 2019 reMarkable AS - http://www.remarkable.com/ + * + * Author: Lars Ivar Miljeteig <lars.ivar.miljeteig@xxxxxxxxxxxxxx> + * + * 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 = 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@xxxxxxxxxxxxxx>"); +MODULE_DESCRIPTION("SY7636A voltage regulator driver"); +MODULE_LICENSE("GPL v2"); -- 2.29.2
