[PATCH v5 3/5] regulator: sy7636a: Initial commit

From: Alistair Francis
Date: Mon Apr 19 2021 - 04:40:47 EST


Initial support for the Silergy SY7636A-regulator Power Management chip.

Signed-off-by: Alistair Francis <alistair@xxxxxxxxxxxxx>
---
v5:
- Simplify the implementation

drivers/regulator/Kconfig | 6 ++
drivers/regulator/Makefile | 1 +
drivers/regulator/sy7636a-regulator.c | 127 ++++++++++++++++++++++++++
include/linux/mfd/sy7636a.h | 1 +
4 files changed, 135 insertions(+)
create mode 100644 drivers/regulator/sy7636a-regulator.c

diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 77c43134bc9e..6d501ce921a8 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -1130,6 +1130,12 @@ 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 44d2f8bf4b74..5a981036a9f0 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -134,6 +134,7 @@ 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..c384c2b6ac46
--- /dev/null
+++ b/drivers/regulator/sy7636a-regulator.c
@@ -0,0 +1,127 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Functions to access SY3686A power management chip voltages
+//
+// Copyright (C) 2019 reMarkable AS - http://www.remarkable.com/
+//
+// Authors: Lars Ivar Miljeteig <lars.ivar.miljeteig@xxxxxxxxxxxxxx>
+// Alistair Francis <alistair@xxxxxxxxxxxxx>
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/gpio/consumer.h>
+#include <linux/mfd/sy7636a.h>
+
+#define SY7636A_POLL_ENABLED_TIME 500
+
+static int sy7636a_get_vcom_voltage_op(struct regulator_dev *rdev)
+{
+ int ret;
+ unsigned int val, val_h;
+
+ ret = regmap_read(rdev->regmap, SY7636A_REG_VCOM_ADJUST_CTRL_L, &val);
+ if (ret)
+ return ret;
+
+ ret = regmap_read(rdev->regmap, SY7636A_REG_VCOM_ADJUST_CTRL_H, &val_h);
+ if (ret)
+ return ret;
+
+ val |= (val_h << VCOM_ADJUST_CTRL_SHIFT);
+
+ return (val & VCOM_ADJUST_CTRL_MASK) * VCOM_ADJUST_CTRL_SCAL;
+}
+
+static int sy7636a_get_status(struct regulator_dev *rdev)
+{
+ struct sy7636a *sy7636a = dev_get_drvdata(rdev->dev.parent);
+ int ret = 0;
+
+ ret = gpiod_get_value_cansleep(sy7636a->pgood_gpio);
+ if (ret < 0)
+ dev_err(&rdev->dev, "Failed to read pgood gpio: %d\n", ret);
+
+ return ret;
+}
+
+static const struct regulator_ops sy7636a_vcom_volt_ops = {
+ .get_voltage = sy7636a_get_vcom_voltage_op,
+ .enable = regulator_enable_regmap,
+ .disable = regulator_disable_regmap,
+ .is_enabled = regulator_is_enabled_regmap,
+ .get_status = sy7636a_get_status,
+};
+
+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,
+ .poll_enabled_time = SY7636A_POLL_ENABLED_TIME,
+ .regulators_node = of_match_ptr("regulators"),
+ .of_match = of_match_ptr("vcom"),
+};
+
+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);
+
+ 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;
+
+ ret = regmap_write(sy7636a->regmap, SY7636A_REG_POWER_ON_DELAY_TIME, 0x0);
+ 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 struct platform_driver sy7636a_regulator_driver = {
+ .driver = {
+ .name = "sy7636a-regulator",
+ },
+ .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");
diff --git a/include/linux/mfd/sy7636a.h b/include/linux/mfd/sy7636a.h
index 43b0db0f8e6d..8e71a6e21791 100644
--- a/include/linux/mfd/sy7636a.h
+++ b/include/linux/mfd/sy7636a.h
@@ -41,6 +41,7 @@
struct sy7636a {
struct device *dev;
struct regmap *regmap;
+ struct gpio_desc *pgood_gpio;
};

#endif /* __LINUX_MFD_SY7636A_H */
--
2.31.1