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1// SPDX-License-Identifier: GPL-2.0-only2//3// Copyright 2020 Google LLC.4 5#include <linux/module.h>6#include <linux/of.h>7#include <linux/platform_data/cros_ec_proto.h>8#include <linux/platform_device.h>9#include <linux/regulator/driver.h>10#include <linux/regulator/machine.h>11#include <linux/regulator/of_regulator.h>12#include <linux/slab.h>13 14struct cros_ec_regulator_data {15 struct regulator_desc desc;16 struct regulator_dev *dev;17 struct cros_ec_device *ec_dev;18 19 u32 index;20 21 u16 *voltages_mV;22 u16 num_voltages;23};24 25static int cros_ec_regulator_enable(struct regulator_dev *dev)26{27 struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);28 struct ec_params_regulator_enable cmd = {29 .index = data->index,30 .enable = 1,31 };32 33 return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd,34 sizeof(cmd), NULL, 0);35}36 37static int cros_ec_regulator_disable(struct regulator_dev *dev)38{39 struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);40 struct ec_params_regulator_enable cmd = {41 .index = data->index,42 .enable = 0,43 };44 45 return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd,46 sizeof(cmd), NULL, 0);47}48 49static int cros_ec_regulator_is_enabled(struct regulator_dev *dev)50{51 struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);52 struct ec_params_regulator_is_enabled cmd = {53 .index = data->index,54 };55 struct ec_response_regulator_is_enabled resp;56 int ret;57 58 ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_IS_ENABLED, &cmd,59 sizeof(cmd), &resp, sizeof(resp));60 if (ret < 0)61 return ret;62 return resp.enabled;63}64 65static int cros_ec_regulator_list_voltage(struct regulator_dev *dev,66 unsigned int selector)67{68 struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);69 70 if (selector >= data->num_voltages)71 return -EINVAL;72 73 return data->voltages_mV[selector] * 1000;74}75 76static int cros_ec_regulator_get_voltage(struct regulator_dev *dev)77{78 struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);79 struct ec_params_regulator_get_voltage cmd = {80 .index = data->index,81 };82 struct ec_response_regulator_get_voltage resp;83 int ret;84 85 ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_VOLTAGE, &cmd,86 sizeof(cmd), &resp, sizeof(resp));87 if (ret < 0)88 return ret;89 return resp.voltage_mv * 1000;90}91 92static int cros_ec_regulator_set_voltage(struct regulator_dev *dev, int min_uV,93 int max_uV, unsigned int *selector)94{95 struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);96 int min_mV = DIV_ROUND_UP(min_uV, 1000);97 int max_mV = max_uV / 1000;98 struct ec_params_regulator_set_voltage cmd = {99 .index = data->index,100 .min_mv = min_mV,101 .max_mv = max_mV,102 };103 104 /*105 * This can happen when the given range [min_uV, max_uV] doesn't106 * contain any voltage that can be represented exactly in mV.107 */108 if (min_mV > max_mV)109 return -EINVAL;110 111 return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_SET_VOLTAGE, &cmd,112 sizeof(cmd), NULL, 0);113}114 115static const struct regulator_ops cros_ec_regulator_voltage_ops = {116 .enable = cros_ec_regulator_enable,117 .disable = cros_ec_regulator_disable,118 .is_enabled = cros_ec_regulator_is_enabled,119 .list_voltage = cros_ec_regulator_list_voltage,120 .get_voltage = cros_ec_regulator_get_voltage,121 .set_voltage = cros_ec_regulator_set_voltage,122};123 124static int cros_ec_regulator_init_info(struct device *dev,125 struct cros_ec_regulator_data *data)126{127 struct ec_params_regulator_get_info cmd = {128 .index = data->index,129 };130 struct ec_response_regulator_get_info resp;131 int ret;132 133 ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_INFO, &cmd,134 sizeof(cmd), &resp, sizeof(resp));135 if (ret < 0)136 return ret;137 138 data->num_voltages =139 min_t(u16, ARRAY_SIZE(resp.voltages_mv), resp.num_voltages);140 data->voltages_mV =141 devm_kmemdup(dev, resp.voltages_mv,142 sizeof(u16) * data->num_voltages, GFP_KERNEL);143 if (!data->voltages_mV)144 return -ENOMEM;145 146 data->desc.n_voltages = data->num_voltages;147 148 /* Make sure the returned name is always a valid string */149 resp.name[ARRAY_SIZE(resp.name) - 1] = '\0';150 data->desc.name = devm_kstrdup(dev, resp.name, GFP_KERNEL);151 if (!data->desc.name)152 return -ENOMEM;153 154 return 0;155}156 157static int cros_ec_regulator_probe(struct platform_device *pdev)158{159 struct device *dev = &pdev->dev;160 struct device_node *np = dev->of_node;161 struct cros_ec_regulator_data *drvdata;162 struct regulator_init_data *init_data;163 struct regulator_config cfg = {};164 struct regulator_desc *desc;165 int ret;166 167 drvdata = devm_kzalloc(168 &pdev->dev, sizeof(struct cros_ec_regulator_data), GFP_KERNEL);169 if (!drvdata)170 return -ENOMEM;171 172 drvdata->ec_dev = dev_get_drvdata(dev->parent);173 desc = &drvdata->desc;174 175 init_data = of_get_regulator_init_data(dev, np, desc);176 if (!init_data)177 return -EINVAL;178 179 ret = of_property_read_u32(np, "reg", &drvdata->index);180 if (ret < 0)181 return ret;182 183 desc->owner = THIS_MODULE;184 desc->type = REGULATOR_VOLTAGE;185 desc->ops = &cros_ec_regulator_voltage_ops;186 187 ret = cros_ec_regulator_init_info(dev, drvdata);188 if (ret < 0)189 return ret;190 191 cfg.dev = &pdev->dev;192 cfg.init_data = init_data;193 cfg.driver_data = drvdata;194 cfg.of_node = np;195 196 drvdata->dev = devm_regulator_register(dev, &drvdata->desc, &cfg);197 if (IS_ERR(drvdata->dev)) {198 ret = PTR_ERR(drvdata->dev);199 dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);200 return ret;201 }202 203 platform_set_drvdata(pdev, drvdata);204 205 return 0;206}207 208static const struct of_device_id regulator_cros_ec_of_match[] = {209 { .compatible = "google,cros-ec-regulator", },210 {}211};212MODULE_DEVICE_TABLE(of, regulator_cros_ec_of_match);213 214static struct platform_driver cros_ec_regulator_driver = {215 .probe = cros_ec_regulator_probe,216 .driver = {217 .name = "cros-ec-regulator",218 .probe_type = PROBE_PREFER_ASYNCHRONOUS,219 .of_match_table = regulator_cros_ec_of_match,220 },221};222 223module_platform_driver(cros_ec_regulator_driver);224 225MODULE_LICENSE("GPL v2");226MODULE_DESCRIPTION("ChromeOS EC controlled regulator");227MODULE_AUTHOR("Pi-Hsun Shih <pihsun@chromium.org>");228