[mirror_ubuntu-jammy-kernel.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_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 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
	25	static int cros_ec_cmd(struct cros_ec_device *ec, u32 version, u32 command,
	26	void outdata, u32 outsize, void indata, u32 insize)
	27	{
	28	struct cros_ec_command *msg;
	29	int ret;
	30
	31	msg = kzalloc(sizeof(*msg) + max(outsize, insize), GFP_KERNEL);
	32	if (!msg)
	33	return -ENOMEM;
	34
	35	msg->version = version;
	36	msg->command = command;
	37	msg->outsize = outsize;
	38	msg->insize = insize;
	39
	40	if (outdata && outsize > 0)
	41	memcpy(msg->data, outdata, outsize);
	42
	43	ret = cros_ec_cmd_xfer_status(ec, msg);
	44	if (ret < 0)
	45	goto cleanup;
	46
	47	if (insize)
	48	memcpy(indata, msg->data, insize);
	49
	50	cleanup:
	51	kfree(msg);
	52	return ret;
	53	}
	54
	55	static int cros_ec_regulator_enable(struct regulator_dev *dev)
	56	{
	57	struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);
	58	struct ec_params_regulator_enable cmd = {
	59	.index = data->index,
	60	.enable = 1,
	61	};
	62
	63	return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd,
	64	sizeof(cmd), NULL, 0);
65	}
66
67	static int cros_ec_regulator_disable(struct regulator_dev *dev)
68	{
69	struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);
70	struct ec_params_regulator_enable cmd = {
71	.index = data->index,
72	.enable = 0,
73	};
74
75	return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_ENABLE, &cmd,
76	sizeof(cmd), NULL, 0);
77	}
78
79	static int cros_ec_regulator_is_enabled(struct regulator_dev *dev)
80	{
81	struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);
82	struct ec_params_regulator_is_enabled cmd = {
83	.index = data->index,
84	};
85	struct ec_response_regulator_is_enabled resp;
86	int ret;
87
88	ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_IS_ENABLED, &cmd,
89	sizeof(cmd), &resp, sizeof(resp));
90	if (ret < 0)
91	return ret;
92	return resp.enabled;
93	}
94
95	static int cros_ec_regulator_list_voltage(struct regulator_dev *dev,
96	unsigned int selector)
97	{
98	struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);
99
100	if (selector >= data->num_voltages)
101	return -EINVAL;
102
103	return data->voltages_mV[selector] * 1000;
104	}
105
106	static int cros_ec_regulator_get_voltage(struct regulator_dev *dev)
107	{
108	struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);
109	struct ec_params_regulator_get_voltage cmd = {
110	.index = data->index,
111	};
112	struct ec_response_regulator_get_voltage resp;
113	int ret;
114
115	ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_VOLTAGE, &cmd,
116	sizeof(cmd), &resp, sizeof(resp));
117	if (ret < 0)
118	return ret;
119	return resp.voltage_mv * 1000;
120	}
121
122	static int cros_ec_regulator_set_voltage(struct regulator_dev *dev, int min_uV,
123	int max_uV, unsigned int *selector)
124	{
125	struct cros_ec_regulator_data *data = rdev_get_drvdata(dev);
126	int min_mV = DIV_ROUND_UP(min_uV, 1000);
127	int max_mV = max_uV / 1000;
128	struct ec_params_regulator_set_voltage cmd = {
129	.index = data->index,
130	.min_mv = min_mV,
131	.max_mv = max_mV,
132	};
133
134	/*
135	* This can happen when the given range [min_uV, max_uV] doesn't
136	* contain any voltage that can be represented exactly in mV.
137	*/
138	if (min_mV > max_mV)
139	return -EINVAL;
140
141	return cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_SET_VOLTAGE, &cmd,
142	sizeof(cmd), NULL, 0);
143	}
144
308e65ad	145	static const struct regulator_ops cros_ec_regulator_voltage_ops = {
8d9f8d57 PHS	146	.enable = cros_ec_regulator_enable,
	147	.disable = cros_ec_regulator_disable,
	148	.is_enabled = cros_ec_regulator_is_enabled,
	149	.list_voltage = cros_ec_regulator_list_voltage,
	150	.get_voltage = cros_ec_regulator_get_voltage,
	151	.set_voltage = cros_ec_regulator_set_voltage,
	152	};
	153
	154	static int cros_ec_regulator_init_info(struct device *dev,
	155	struct cros_ec_regulator_data *data)
	156	{
	157	struct ec_params_regulator_get_info cmd = {
	158	.index = data->index,
	159	};
	160	struct ec_response_regulator_get_info resp;
	161	int ret;
	162
	163	ret = cros_ec_cmd(data->ec_dev, 0, EC_CMD_REGULATOR_GET_INFO, &cmd,
	164	sizeof(cmd), &resp, sizeof(resp));
	165	if (ret < 0)
	166	return ret;
	167
	168	data->num_voltages =
	169	min_t(u16, ARRAY_SIZE(resp.voltages_mv), resp.num_voltages);
	170	data->voltages_mV =
	171	devm_kmemdup(dev, resp.voltages_mv,
	172	sizeof(u16) * data->num_voltages, GFP_KERNEL);
ce410900 AL	173	if (!data->voltages_mV)
	174	return -ENOMEM;
	175
8d9f8d57 PHS	176	data->desc.n_voltages = data->num_voltages;
	177
	178	/* Make sure the returned name is always a valid string */
	179	resp.name[ARRAY_SIZE(resp.name) - 1] = '\0';
	180	data->desc.name = devm_kstrdup(dev, resp.name, GFP_KERNEL);
	181	if (!data->desc.name)
	182	return -ENOMEM;
	183
	184	return 0;
	185	}
	186
	187	static int cros_ec_regulator_probe(struct platform_device *pdev)
	188	{
	189	struct device *dev = &pdev->dev;
	190	struct device_node *np = dev->of_node;
	191	struct cros_ec_regulator_data *drvdata;
	192	struct regulator_init_data *init_data;
	193	struct regulator_config cfg = {};
	194	struct regulator_desc *desc;
	195	int ret;
	196
	197	drvdata = devm_kzalloc(
	198	&pdev->dev, sizeof(struct cros_ec_regulator_data), GFP_KERNEL);
	199	if (!drvdata)
	200	return -ENOMEM;
	201
	202	drvdata->ec_dev = dev_get_drvdata(dev->parent);
	203	desc = &drvdata->desc;
	204
	205	init_data = of_get_regulator_init_data(dev, np, desc);
	206	if (!init_data)
	207	return -EINVAL;
	208
	209	ret = of_property_read_u32(np, "reg", &drvdata->index);
	210	if (ret < 0)
	211	return ret;
	212
	213	desc->owner = THIS_MODULE;
	214	desc->type = REGULATOR_VOLTAGE;
	215	desc->ops = &cros_ec_regulator_voltage_ops;
	216
	217	ret = cros_ec_regulator_init_info(dev, drvdata);
	218	if (ret < 0)
	219	return ret;
	220
	221	cfg.dev = &pdev->dev;
	222	cfg.init_data = init_data;
	223	cfg.driver_data = drvdata;
	224	cfg.of_node = np;
	225
	226	drvdata->dev = devm_regulator_register(dev, &drvdata->desc, &cfg);
	227	if (IS_ERR(drvdata->dev)) {
3d681804	228	ret = PTR_ERR(drvdata->dev);
8d9f8d57	229	dev_err(&pdev->dev, "Failed to register regulator: %d\n", ret);
3d681804	230	return ret;
8d9f8d57 PHS	231	}
	232
	233	platform_set_drvdata(pdev, drvdata);
	234
	235	return 0;
8d9f8d57 PHS	236	}
	237
	238	static const struct of_device_id regulator_cros_ec_of_match[] = {
	239	{ .compatible = "google,cros-ec-regulator", },
	240	{}
	241	};
	242	MODULE_DEVICE_TABLE(of, regulator_cros_ec_of_match);
	243
	244	static struct platform_driver cros_ec_regulator_driver = {
	245	.probe = cros_ec_regulator_probe,
	246	.driver = {
	247	.name = "cros-ec-regulator",
	248	.of_match_table = regulator_cros_ec_of_match,
	249	},
	250	};
	251
	252	module_platform_driver(cros_ec_regulator_driver);
	253
	254	MODULE_LICENSE("GPL v2");
	255	MODULE_DESCRIPTION("ChromeOS EC controlled regulator");
	256	MODULE_AUTHOR("Pi-Hsun Shih <pihsun@chromium.org>");