From 8d9f8d57e023893bfa708d83e3a787e77766a378 Mon Sep 17 00:00:00 2001 From: Pi-Hsun Shih Date: Fri, 12 Jun 2020 12:05:20 +0800 Subject: [PATCH] regulator: Add driver for cros-ec-regulator Add driver for cros-ec-regulator, representing a voltage regulator that is connected and controlled by ChromeOS EC, and is controlled by kernel with EC host commands. Signed-off-by: Pi-Hsun Shih Reviewed-by: Prashant Malani Reviewed-by: Enric Balletbo i Serra Link: https://lore.kernel.org/r/20200612040526.192878-4-pihsun@chromium.org Signed-off-by: Mark Brown --- drivers/regulator/Kconfig | 10 + drivers/regulator/Makefile | 1 + drivers/regulator/cros-ec-regulator.c | 257 ++++++++++++++++++++++++++ 3 files changed, 268 insertions(+) create mode 100644 drivers/regulator/cros-ec-regulator.c diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 8f677f5d79b4..c398e90e0e73 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -238,6 +238,16 @@ config REGULATOR_CPCAP Say y here for CPCAP regulator found on some Motorola phones and tablets such as Droid 4. +config REGULATOR_CROS_EC + tristate "ChromeOS EC regulators" + depends on CROS_EC && OF + help + This driver supports voltage regulators that is connected to ChromeOS + EC and controlled through EC host commands. + + This driver can also be built as a module. If so, the module + will be called cros-ec-regulator. + config REGULATOR_DA903X tristate "Dialog Semiconductor DA9030/DA9034 regulators" depends on PMIC_DA903X diff --git a/drivers/regulator/Makefile b/drivers/regulator/Makefile index e8f163371071..46592c160d22 100644 --- a/drivers/regulator/Makefile +++ b/drivers/regulator/Makefile @@ -13,6 +13,7 @@ obj-$(CONFIG_REGULATOR_USERSPACE_CONSUMER) += userspace-consumer.o obj-$(CONFIG_REGULATOR_88PG86X) += 88pg86x.o obj-$(CONFIG_REGULATOR_88PM800) += 88pm800-regulator.o obj-$(CONFIG_REGULATOR_88PM8607) += 88pm8607.o +obj-$(CONFIG_REGULATOR_CROS_EC) += cros-ec-regulator.o obj-$(CONFIG_REGULATOR_CPCAP) += cpcap-regulator.o obj-$(CONFIG_REGULATOR_AAT2870) += aat2870-regulator.o obj-$(CONFIG_REGULATOR_AB3100) += ab3100.o diff --git a/drivers/regulator/cros-ec-regulator.c b/drivers/regulator/cros-ec-regulator.c new file mode 100644 index 000000000000..35f97246bc48 --- /dev/null +++ b/drivers/regulator/cros-ec-regulator.c @@ -0,0 +1,257 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Copyright 2020 Google LLC. + +#include +#include +#include +#include +#include +#include +#include +#include + +struct cros_ec_regulator_data { + struct regulator_desc desc; + struct regulator_dev *dev; + struct cros_ec_device *ec_dev; + + u32 index; + + u16 *voltages_mV; + u16 num_voltages; +}; + +static int cros_ec_cmd(struct cros_ec_device *ec, u32 version, u32 command, + void *outdata, u32 outsize, void *indata, u32 insize) +{ + struct cros_ec_command *msg; + int ret; + + msg = kzalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL); + if (!msg) + return -ENOMEM; + + msg->version = version; + msg->command = command; + msg->outsize = outsize; + msg->insize = insize; + + if (outdata && outsize > 0) + memcpy(msg->data, outdata, outsize); + + ret = cros_ec_cmd_xfer_status(ec, msg); + if (ret < 0) + goto cleanup; + + if (insize) + memcpy(indata, msg->data, insize); + +cleanup: + kfree(msg); + return ret; +} + +static int cros_ec_regulator_enable(struct regulator_dev *dev) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + struct ec_params_regulator_enable cmd = { + .index = data->index, + .enable = 1, + }; + + return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd, + sizeof(cmd), NULL, 0); +} + +static int cros_ec_regulator_disable(struct regulator_dev *dev) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + struct ec_params_regulator_enable cmd = { + .index = data->index, + .enable = 0, + }; + + return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd, + sizeof(cmd), NULL, 0); +} + +static int cros_ec_regulator_is_enabled(struct regulator_dev *dev) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + struct ec_params_regulator_is_enabled cmd = { + .index = data->index, + }; + struct ec_response_regulator_is_enabled resp; + int ret; + + ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_IS_ENABLED, &cmd, + sizeof(cmd), &resp, sizeof(resp)); + if (ret < 0) + return ret; + return resp.enabled; +} + +static int cros_ec_regulator_list_voltage(struct regulator_dev *dev, + unsigned int selector) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + + if (selector >= data->num_voltages) + return -EINVAL; + + return data->voltages_mV[selector] * 1000; +} + +static int cros_ec_regulator_get_voltage(struct regulator_dev *dev) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + struct ec_params_regulator_get_voltage cmd = { + .index = data->index, + }; + struct ec_response_regulator_get_voltage resp; + int ret; + + ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_VOLTAGE, &cmd, + sizeof(cmd), &resp, sizeof(resp)); + if (ret < 0) + return ret; + return resp.voltage_mv * 1000; +} + +static int cros_ec_regulator_set_voltage(struct regulator_dev *dev, int min_uV, + int max_uV, unsigned int *selector) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + int min_mV = DIV_ROUND_UP(min_uV, 1000); + int max_mV = max_uV / 1000; + struct ec_params_regulator_set_voltage cmd = { + .index = data->index, + .min_mv = min_mV, + .max_mv = max_mV, + }; + + /* + * This can happen when the given range [min_uV, max_uV] doesn't + * contain any voltage that can be represented exactly in mV. + */ + if (min_mV > max_mV) + return -EINVAL; + + return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_SET_VOLTAGE, &cmd, + sizeof(cmd), NULL, 0); +} + +static struct regulator_ops cros_ec_regulator_voltage_ops = { + .enable = cros_ec_regulator_enable, + .disable = cros_ec_regulator_disable, + .is_enabled = cros_ec_regulator_is_enabled, + .list_voltage = cros_ec_regulator_list_voltage, + .get_voltage = cros_ec_regulator_get_voltage, + .set_voltage = cros_ec_regulator_set_voltage, +}; + +static int cros_ec_regulator_init_info(struct device *dev, + struct cros_ec_regulator_data *data) +{ + struct ec_params_regulator_get_info cmd = { + .index = data->index, + }; + struct ec_response_regulator_get_info resp; + int ret; + + ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_INFO, &cmd, + sizeof(cmd), &resp, sizeof(resp)); + if (ret < 0) + return ret; + + data->num_voltages = + min_t(u16, ARRAY_SIZE(resp.voltages_mv), resp.num_voltages); + data->voltages_mV = + devm_kmemdup(dev, resp.voltages_mv, + sizeof(u16) * data->num_voltages, GFP_KERNEL); + data->desc.n_voltages = data->num_voltages; + + /* Make sure the returned name is always a valid string */ + resp.name[ARRAY_SIZE(resp.name) - 1] = '\0'; + data->desc.name = devm_kstrdup(dev, resp.name, GFP_KERNEL); + if (!data->desc.name) + return -ENOMEM; + + return 0; +} + +static int cros_ec_regulator_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct device_node *np = dev->of_node; + struct cros_ec_regulator_data *drvdata; + struct regulator_init_data *init_data; + struct regulator_config cfg = {}; + struct regulator_desc *desc; + int ret; + + drvdata = devm_kzalloc( + &pdev->dev, sizeof(struct cros_ec_regulator_data), GFP_KERNEL); + if (!drvdata) + return -ENOMEM; + + drvdata->ec_dev = dev_get_drvdata(dev->parent); + desc = &drvdata->desc; + + init_data = of_get_regulator_init_data(dev, np, desc); + if (!init_data) + return -EINVAL; + + ret = of_property_read_u32(np, "reg", &drvdata->index); + if (ret < 0) + return ret; + + desc->owner = THIS_MODULE; + desc->type = REGULATOR_VOLTAGE; + desc->ops = &cros_ec_regulator_voltage_ops; + + ret = cros_ec_regulator_init_info(dev, drvdata); + if (ret < 0) + return ret; + + cfg.dev = &pdev->dev; + cfg.init_data = init_data; + cfg.driver_data = drvdata; + cfg.of_node = np; + + drvdata->dev = devm_regulator_register(dev, &drvdata->desc, &cfg); + if (IS_ERR(drvdata->dev)) { + ret = PTR_ERR(drvdata->dev); + dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret); + goto free_name; + } + + platform_set_drvdata(pdev, drvdata); + + return 0; + +free_name: + kfree(desc->name); + return ret; +} + +static const struct of_device_id regulator_cros_ec_of_match[] = { + { .compatible = "google,cros-ec-regulator", }, + {} +}; +MODULE_DEVICE_TABLE(of, regulator_cros_ec_of_match); + +static struct platform_driver cros_ec_regulator_driver = { + .probe = cros_ec_regulator_probe, + .driver = { + .name = "cros-ec-regulator", + .of_match_table = regulator_cros_ec_of_match, + }, +}; + +module_platform_driver(cros_ec_regulator_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("ChromeOS EC controlled regulator"); +MODULE_AUTHOR("Pi-Hsun Shih ");