diff options
Diffstat (limited to 'drivers/regulator/sun20i-regulator.c')
| -rw-r--r-- | drivers/regulator/sun20i-regulator.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/regulator/sun20i-regulator.c b/drivers/regulator/sun20i-regulator.c new file mode 100644 index 0000000000..e09be44859 --- /dev/null +++ b/drivers/regulator/sun20i-regulator.c @@ -0,0 +1,157 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Copyright (c) 2021-2022 Samuel Holland <samuel@sholland.org> +// + +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/regulator/driver.h> + +#define SUN20I_SYS_LDO_CTRL_REG 0x150 + +struct sun20i_regulator_data { + const struct regulator_desc *descs; + unsigned int ndescs; +}; + +/* regulator_list_voltage_linear() modified for the non-integral uV_step. */ +static int sun20i_d1_system_ldo_list_voltage(struct regulator_dev *rdev, + unsigned int selector) +{ + const struct regulator_desc *desc = rdev->desc; + unsigned int fraction, uV; + + if (selector >= desc->n_voltages) + return -EINVAL; + + uV = desc->min_uV + (desc->uV_step * selector); + fraction = selector + (desc->min_uV % 4); + + if (uV > 1606667) + uV += 6667; + else + fraction++; + + /* Produce correctly-rounded absolute voltages. */ + return uV + (fraction / 3); +} + +static const struct regulator_ops sun20i_d1_system_ldo_ops = { + .list_voltage = sun20i_d1_system_ldo_list_voltage, + .map_voltage = regulator_map_voltage_ascend, + .set_voltage_sel = regulator_set_voltage_sel_regmap, + .get_voltage_sel = regulator_get_voltage_sel_regmap, +}; + +static const struct regulator_desc sun20i_d1_system_ldo_descs[] = { + { + .name = "ldoa", + .supply_name = "ldo-in", + .of_match = "ldoa", + .ops = &sun20i_d1_system_ldo_ops, + .type = REGULATOR_VOLTAGE, + .owner = THIS_MODULE, + .n_voltages = 32, + .min_uV = 1593333, + .uV_step = 13333, /* repeating */ + .vsel_reg = SUN20I_SYS_LDO_CTRL_REG, + .vsel_mask = GENMASK(7, 0), + }, + { + .name = "ldob", + .supply_name = "ldo-in", + .of_match = "ldob", + .ops = &sun20i_d1_system_ldo_ops, + .type = REGULATOR_VOLTAGE, + .owner = THIS_MODULE, + .n_voltages = 64, + .min_uV = 1166666, + .uV_step = 13333, /* repeating */ + .vsel_reg = SUN20I_SYS_LDO_CTRL_REG, + .vsel_mask = GENMASK(15, 8), + }, +}; + +static const struct sun20i_regulator_data sun20i_d1_system_ldos = { + .descs = sun20i_d1_system_ldo_descs, + .ndescs = ARRAY_SIZE(sun20i_d1_system_ldo_descs), +}; + +static struct regmap *sun20i_regulator_get_regmap(struct device *dev) +{ + struct regmap *regmap; + + /* + * First try the syscon interface. The system control device is not + * compatible with "syscon", so fall back to getting the regmap from + * its platform device. This is ugly, but required for devicetree + * backward compatibility. + */ + regmap = syscon_node_to_regmap(dev->parent->of_node); + if (!IS_ERR(regmap)) + return regmap; + + regmap = dev_get_regmap(dev->parent, NULL); + if (regmap) + return regmap; + + return ERR_PTR(-EPROBE_DEFER); +} + +static int sun20i_regulator_probe(struct platform_device *pdev) +{ + const struct sun20i_regulator_data *data; + struct device *dev = &pdev->dev; + struct regulator_config config; + struct regmap *regmap; + + data = of_device_get_match_data(dev); + if (!data) + return -EINVAL; + + regmap = sun20i_regulator_get_regmap(dev); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), "Failed to get regmap\n"); + + config = (struct regulator_config) { + .dev = dev, + .regmap = regmap, + }; + + for (unsigned int i = 0; i < data->ndescs; ++i) { + const struct regulator_desc *desc = &data->descs[i]; + struct regulator_dev *rdev; + + rdev = devm_regulator_register(dev, desc, &config); + if (IS_ERR(rdev)) + return PTR_ERR(rdev); + } + + return 0; +} + +static const struct of_device_id sun20i_regulator_of_match[] = { + { + .compatible = "allwinner,sun20i-d1-system-ldos", + .data = &sun20i_d1_system_ldos, + }, + { }, +}; +MODULE_DEVICE_TABLE(of, sun20i_regulator_of_match); + +static struct platform_driver sun20i_regulator_driver = { + .probe = sun20i_regulator_probe, + .driver = { + .name = "sun20i-regulator", + .of_match_table = sun20i_regulator_of_match, + }, +}; +module_platform_driver(sun20i_regulator_driver); + +MODULE_AUTHOR("Samuel Holland <samuel@sholland.org>"); +MODULE_DESCRIPTION("Allwinner D1 internal LDO driver"); +MODULE_LICENSE("GPL"); |