[linux-block.git] / drivers / regulator / cros-ec-regulator.c

// SPDX-License-Identifier: GPL-2.0-only
//
// 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_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 const 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);
	if (!data->voltages_mV)
		return -ENOMEM;

	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);
		return ret;
	}

	platform_set_drvdata(pdev, drvdata);

	return 0;
}

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 <pihsun@chromium.org>");
Commit	Line	Data
8d9f8d57 PHS	1	// SPDX-License-Identifier: GPL-2.0-only
	2	//
	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
	14	struct 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
8d9f8d57 PHS	25	static 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
b1d288d9 PM	33	return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd,
b1d288d9 PM	34	sizeof(cmd), NULL, 0);
8d9f8d57 PHS	35	}
	36
	37	static 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
b1d288d9 PM	45	return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd,
b1d288d9 PM	46	sizeof(cmd), NULL, 0);
8d9f8d57 PHS	47	}
	48
	49	static 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
b1d288d9 PM	58	ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_IS_ENABLED, &cmd,
b1d288d9 PM	59	sizeof(cmd), &resp, sizeof(resp));
8d9f8d57 PHS	60	if (ret < 0)
	61	return ret;
	62	return resp.enabled;
	63	}
	64
	65	static 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
	76	static 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
b1d288d9 PM	85	ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_VOLTAGE, &cmd,
b1d288d9 PM	86	sizeof(cmd), &resp, sizeof(resp));
8d9f8d57 PHS	87	if (ret < 0)
	88	return ret;
	89	return resp.voltage_mv * 1000;
	90	}
	91
	92	static 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't
	106	* contain any voltage that can be represented exactly in mV.
	107	*/
	108	if (min_mV > max_mV)
	109	return -EINVAL;
	110
b1d288d9 PM	111	return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_SET_VOLTAGE, &cmd,
b1d288d9 PM	112	sizeof(cmd), NULL, 0);
8d9f8d57 PHS	113	}
8d9f8d57 PHS	114
308e65ad	115	static const struct regulator_ops cros_ec_regulator_voltage_ops = {
8d9f8d57 PHS	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
	124	static 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
b1d288d9 PM	133	ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_INFO, &cmd,
b1d288d9 PM	134	sizeof(cmd), &resp, sizeof(resp));
8d9f8d57 PHS	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);
ce410900 AL	143	if (!data->voltages_mV)
	144	return -ENOMEM;
	145
8d9f8d57 PHS	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
	157	static 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)) {
3d681804	198	ret = PTR_ERR(drvdata->dev);
8d9f8d57	199	dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
3d681804	200	return ret;
8d9f8d57 PHS	201	}
	202
	203	platform_set_drvdata(pdev, drvdata);
	204
	205	return 0;
8d9f8d57 PHS	206	}
	207
	208	static const struct of_device_id regulator_cros_ec_of_match[] = {
	209	{ .compatible = "google,cros-ec-regulator", },
	210	{}
	211	};
	212	MODULE_DEVICE_TABLE(of, regulator_cros_ec_of_match);
	213
	214	static struct platform_driver cros_ec_regulator_driver = {
	215	.probe = cros_ec_regulator_probe,
	216	.driver = {
	217	.name = "cros-ec-regulator",
	218	.of_match_table = regulator_cros_ec_of_match,
	219	},
	220	};
	221
	222	module_platform_driver(cros_ec_regulator_driver);
	223
	224	MODULE_LICENSE("GPL v2");
	225	MODULE_DESCRIPTION("ChromeOS EC controlled regulator");
	226	MODULE_AUTHOR("Pi-Hsun Shih <pihsun@chromium.org>");