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 <pih...@chromium.org> --- This patch contains function cros_ec_cmd that is copied from the series: https://lore.kernel.org/patchwork/project/lkml/list/?series=428457. I can't find the first patch in that v2 series, so the function is modified from v1 of that series according to reviewers comment: https://lore.kernel.org/patchwork/patch/1188110/ I copied the function instead of depending on that series since I feel the function is small enough, and the series has stalled for some time. --- drivers/regulator/Kconfig | 7 + drivers/regulator/Makefile | 1 + drivers/regulator/cros-ec-regulator.c | 261 ++++++++++++++++++ .../linux/platform_data/cros_ec_commands.h | 82 ++++++ 4 files changed, 351 insertions(+) create mode 100644 drivers/regulator/cros-ec-regulator.c diff --git a/drivers/regulator/Kconfig b/drivers/regulator/Kconfig index 8f677f5d79b4..3543e0fc54ca 100644 --- a/drivers/regulator/Kconfig +++ b/drivers/regulator/Kconfig @@ -238,6 +238,13 @@ 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 + help + This driver supports voltage regulators that is connected to ChromeOS + EC and controlled through EC host commands. + 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..495006f6381c --- /dev/null +++ b/drivers/regulator/cros-ec-regulator.c @@ -0,0 +1,261 @@ +// SPDX-License-Identifier: GPL-2.0 +// +// Copyright 2020 Google LLC. + +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_data/cros_ec_proto.h> +#include <linux/platform_device.h> +#include <linux/regulator/driver.h> +#include <linux/regulator/machine.h> +#include <linux/regulator/of_regulator.h> +#include <linux/slab.h> + +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) { + dev_warn(ec->dev, "Command failed: %d\n", msg->result); + goto cleanup; + } + + if (insize) + memcpy(indata, msg->data, insize); + +cleanup: + kfree(msg); + return ret; +} + +static int cros_ec_regulator_set_state(struct regulator_dev *dev, bool enable) +{ + struct cros_ec_regulator_data *data = rdev_get_drvdata(dev); + struct ec_params_regulator_enable cmd = { + .index = data->index, + .enable = enable ? 1 : 0, + }; + + return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd, + sizeof(cmd), NULL, 0); +} + +static int cros_ec_regulator_enable(struct regulator_dev *dev) +{ + return cros_ec_regulator_set_state(dev, true); +} + +static int cros_ec_regulator_disable(struct regulator_dev *dev) +{ + return cros_ec_regulator_set_state(dev, false); +} + +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, + }; + + 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; + data->desc.name = kstrndup(resp.name, sizeof(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, "google,remote-regulator", + &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 = regulator_register(&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 int cros_ec_regulator_remove(struct platform_device *pdev) +{ + struct cros_ec_regulator_data *drvdata = platform_get_drvdata(pdev); + + kfree(drvdata->desc.name); + + return 0; +} + +#if defined(CONFIG_OF) +static const struct of_device_id regulator_cros_ec_of_match[] = { + { .compatible = "regulator-cros-ec", }, + {}, +}; +MODULE_DEVICE_TABLE(of, regulator_cros_ec_of_match); +#endif + +static struct platform_driver cros_ec_regulator_driver = { + .probe = cros_ec_regulator_probe, + .remove = cros_ec_regulator_remove, + .driver = { + .name = "cros-ec-regulator", + .of_match_table = of_match_ptr(regulator_cros_ec_of_match), + }, +}; + +module_platform_driver(cros_ec_regulator_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_DESCRIPTION("ChromeOS EC controlled regulator"); diff --git a/include/linux/platform_data/cros_ec_commands.h b/include/linux/platform_data/cros_ec_commands.h index 69210881ebac..a417b51b5764 100644 --- a/include/linux/platform_data/cros_ec_commands.h +++ b/include/linux/platform_data/cros_ec_commands.h @@ -5430,6 +5430,88 @@ struct ec_response_rollback_info { /* Issue AP reset */ #define EC_CMD_AP_RESET 0x0125 +/*****************************************************************************/ +/* Voltage regulator controls */ + +/* + * Get basic info of voltage regulator for given index. + * + * Returns the regulator name and supported voltage list in mV. + */ +#define EC_CMD_REGULATOR_GET_INFO 0x012B + +/* Maximum length of regulator name */ +#define EC_REGULATOR_NAME_MAX_LEN 16 + +/* Maximum length of the supported voltage list. */ +#define EC_REGULATOR_VOLTAGE_MAX_COUNT 16 + +struct ec_params_regulator_get_info { + uint32_t index; +} __ec_align4; + +struct ec_response_regulator_get_info { + char name[EC_REGULATOR_NAME_MAX_LEN]; + uint16_t num_voltages; + uint16_t voltages_mv[EC_REGULATOR_VOLTAGE_MAX_COUNT]; +} __ec_align1; + +/* + * Configure the regulator as enabled / disabled. + */ +#define EC_CMD_REGULATOR_ENABLE 0x012C + +struct ec_params_regulator_enable { + uint32_t index; + uint8_t enable; +} __ec_align4; + +/* + * Query if the regulator is enabled. + * + * Returns 1 if the regulator is enabled, 0 if not. + */ +#define EC_CMD_REGULATOR_IS_ENABLED 0x012D + +struct ec_params_regulator_is_enabled { + uint32_t index; +} __ec_align4; + +struct ec_response_regulator_is_enabled { + uint8_t enabled; +} __ec_align1; + +/* + * Set voltage for the voltage regulator within the range specified. + * + * The driver should select the voltage in range closest to min_mv. + * + * Also note that this might be called before the regulator is enabled, and the + * setting should be in effect after the regulator is enabled. + */ +#define EC_CMD_REGULATOR_SET_VOLTAGE 0x012E + +struct ec_params_regulator_set_voltage { + uint32_t index; + uint32_t min_mv; + uint32_t max_mv; +} __ec_align4; + +/* + * Get the currently configured voltage for the voltage regulator. + * + * Note that this might be called before the regulator is enabled. + */ +#define EC_CMD_REGULATOR_GET_VOLTAGE 0x012F + +struct ec_params_regulator_get_voltage { + uint32_t index; +} __ec_align4; + +struct ec_response_regulator_get_voltage { + uint32_t voltage_mv; +} __ec_align4; + /*****************************************************************************/ /* The command range 0x200-0x2FF is reserved for Rotor. */ -- 2.27.0.278.ge193c7cf3a9-goog
