From: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Introduce a driver to control the Maxim MAX20411 family of
high-efficiency, syncrhonous step-down converters.
Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxx>
Signed-off-by: Bjorn Andersson <quic_bjorande@xxxxxxxxxxx>
---
Changes since v1:
- Extracted regulator_desc initialization from max20411_probe()
drivers/regulator/Kconfig | 8 ++
drivers/regulator/Makefile | 1 +
drivers/regulator/max20411-regulator.c | 163 +++++++++++++++++++++++++
3 files changed, 172 insertions(+)
create mode 100644 drivers/regulator/max20411-regulator.c
diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig
index 820c9a0788e5..aae28d0a489c 100644
--- a/drivers/regulator/Kconfig
+++ b/drivers/regulator/Kconfig
@@ -655,6 +655,14 @@ config REGULATOR_MAX20086
protectorvia I2C bus. The regulator has 2 or 4 outputs depending on
the device model. This driver is only capable to turn on/off them.
+config REGULATOR_MAX20411
+ tristate "Maxim MAX20411 High-Efficiency Single Step-Down Converter"
+ depends on I2C
+ select REGMAP_I2C
+ help
+ This driver controls the Maxim MAX20411 family of high-efficiency,
+ syncrhonous step-down converters.
+
config REGULATOR_MAX77686
tristate "Maxim 77686 regulator"
depends on MFD_MAX77686 || COMPILE_TEST
diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile
index b9f5eb35bf5f..ee383d8fc835 100644
--- a/drivers/regulator/Makefile
+++ b/drivers/regulator/Makefile
@@ -80,6 +80,7 @@ obj-$(CONFIG_REGULATOR_MAX8973) += max8973-regulator.o
obj-$(CONFIG_REGULATOR_MAX8997) += max8997-regulator.o
obj-$(CONFIG_REGULATOR_MAX8998) += max8998.o
obj-$(CONFIG_REGULATOR_MAX20086) += max20086-regulator.o
+obj-$(CONFIG_REGULATOR_MAX20411) += max20411-regulator.o
obj-$(CONFIG_REGULATOR_MAX77686) += max77686-regulator.o
obj-$(CONFIG_REGULATOR_MAX77693) += max77693-regulator.o
obj-$(CONFIG_REGULATOR_MAX77802) += max77802-regulator.o
diff --git a/drivers/regulator/max20411-regulator.c b/drivers/regulator/max20411-regulator.c
new file mode 100644
index 000000000000..69f04cbe69f1
--- /dev/null
+++ b/drivers/regulator/max20411-regulator.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (c) 2021, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2022, Linaro Ltd.
+ */
+
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/regulator/driver.h>
+#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
+
+#define MAX20411_UV_STEP 6250
+#define MAX20411_BASE_UV 243750
+#define MAX20411_MIN_SEL 41 /* 0.5V */
+#define MAX20411_MAX_SEL 165 /* 1.275V */
+#define MAX20411_VID_OFFSET 0x7
+#define MAX20411_VID_MASK 0xff
+#define MAX20411_SLEW_OFFSET 0x6
+#define MAX20411_SLEW_DVS_MASK 0xc
+#define MAX20411_SLEW_SR_MASK 0x3
+
+struct max20411 {
+ struct device *dev;
+ struct device_node *of_node;
+ struct regulator_desc desc;
+ struct regulator_dev *rdev;
+ struct regmap *regmap;
+};
+
+static const unsigned int max20411_slew_rates[] = { 13100, 6600, 3300, 1600 };
+
+static int max20411_enable_time(struct regulator_dev *rdev)
+{
+ int voltage, rate, ret;
+ unsigned int val;
+
+ /* get voltage */
+ ret = regmap_read(rdev->regmap, rdev->desc->vsel_reg, &val);
+ if (ret)
+ return ret;
+
+ val &= rdev->desc->vsel_mask;
+ voltage = regulator_list_voltage_linear(rdev, val);
+
+ /* get rate */
+ ret = regmap_read(rdev->regmap, MAX20411_SLEW_OFFSET, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(MAX20411_SLEW_SR_MASK, val);
+ rate = max20411_slew_rates[val];
+
+ return DIV_ROUND_UP(voltage, rate);
+}
+
+static const struct regmap_config max20411_regmap_config = {
+ .reg_bits = 8,
+ .val_bits = 8,
+ .max_register = 0xe,
+};
+
+static const struct regulator_ops max20411_ops = {
+ .get_voltage_sel = regulator_get_voltage_sel_regmap,
+ .set_voltage_sel = regulator_set_voltage_sel_regmap,
+ .list_voltage = regulator_list_voltage_linear,
+ .enable_time = max20411_enable_time,
+};
+
+static const struct regulator_desc max20411_desc = {
+ .ops = &max20411_ops,
+ .owner = THIS_MODULE,
+ .type = REGULATOR_VOLTAGE,
+ .supply_name = "vin",
+ .name = "max20411",
+
+ /*
+ * voltage = 0.24375V + selector * 6.25mV
+ * with valid selector between 41 to 165 (0.5V to 1.275V)
+ */
+ .min_uV = MAX20411_BASE_UV,
+ .uV_step = MAX20411_UV_STEP,
+ .linear_min_sel = MAX20411_MIN_SEL,
+ .n_voltages = MAX20411_MAX_SEL,
+
+ .vsel_reg = MAX20411_VID_OFFSET,
+ .vsel_mask = MAX20411_VID_MASK,
+
+ .ramp_reg = MAX20411_SLEW_OFFSET,
+ .ramp_mask = MAX20411_SLEW_DVS_MASK,
+ .ramp_delay_table = max20411_slew_rates,
+ .n_ramp_values = ARRAY_SIZE(max20411_slew_rates),
+};
+
+static int max20411_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct regulator_init_data *init_data;
+ struct device *dev = &client->dev;
+ struct regulator_config cfg = {};
+ struct max20411 *max20411;
+
+ max20411 = devm_kzalloc(dev, sizeof(*max20411), GFP_KERNEL);
+ if (!max20411)
+ return -ENOMEM;
+
+ max20411->regmap = devm_regmap_init_i2c(client, &max20411_regmap_config);
+ if (IS_ERR(max20411->regmap)) {
+ dev_err(dev, "Failed to allocate regmap!\n");
+ return PTR_ERR(max20411->regmap);
+ }
+
+ max20411->dev = dev;
+ max20411->of_node = dev->of_node;
+
+ max20411->desc = max20411_desc;
+ init_data = of_get_regulator_init_data(max20411->dev, max20411->of_node, &max20411->desc);
+ if (!init_data)
+ return -ENODATA;
+
+ cfg.dev = max20411->dev;
+ cfg.init_data = init_data;
+ cfg.of_node = max20411->of_node;
+ cfg.driver_data = max20411;
+
+ cfg.ena_gpiod = gpiod_get(max20411->dev, "enable", GPIOD_ASIS);
+ if (IS_ERR(cfg.ena_gpiod))
+ return dev_err_probe(dev, PTR_ERR(cfg.ena_gpiod),
+ "unable to acquire enable gpio\n");
+
+ max20411->rdev = devm_regulator_register(max20411->dev, &max20411->desc, &cfg);
+ if (IS_ERR(max20411->rdev))
+ dev_err(max20411->dev, "Failed to register regulator\n");
+
+ return PTR_ERR_OR_ZERO(max20411->rdev);
+}
+
+static const struct of_device_id of_max20411_match_tbl[] = {
+ { .compatible = "maxim,max20411", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, of_max20411_match_tbl);
+
+static const struct i2c_device_id max20411_id[] = {
+ { "max20411", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, max20411_id);
+
+static struct i2c_driver max20411_i2c_driver = {
+ .driver = {
+ .name = "max20411",
+ .of_match_table = of_max20411_match_tbl,
+ },
+ .probe = max20411_probe,
+ .id_table = max20411_id,
+};
+module_i2c_driver(max20411_i2c_driver);
+
+MODULE_LICENSE("GPL");
--
2.25.1
