[linux-2.6-block.git] / drivers / hwmon / scmi-hwmon.c

// SPDX-License-Identifier: GPL-2.0
/*
 * System Control and Management Interface(SCMI) based hwmon sensor driver
 *
 * Copyright (C) 2018 ARM Ltd.
 * Sudeep Holla <sudeep.holla@arm.com>
 */

#include <linux/hwmon.h>
#include <linux/module.h>
#include <linux/scmi_protocol.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/thermal.h>

struct scmi_sensors {
	const struct scmi_handle *handle;
	const struct scmi_sensor_info **info[hwmon_max];
};

static inline u64 __pow10(u8 x)
{
	u64 r = 1;

	while (x--)
		r *= 10;

	return r;
}

static int scmi_hwmon_scale(const struct scmi_sensor_info *sensor, u64 *value)
{
	s8 scale = sensor->scale;
	u64 f;

	switch (sensor->type) {
	case TEMPERATURE_C:
	case VOLTAGE:
	case CURRENT:
		scale += 3;
		break;
	case POWER:
	case ENERGY:
		scale += 6;
		break;
	default:
		break;
	}

	if (scale == 0)
		return 0;

	if (abs(scale) > 19)
		return -E2BIG;

	f = __pow10(abs(scale));
	if (scale > 0)
		*value *= f;
	else
		*value = div64_u64(*value, f);

	return 0;
}

static int scmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
			   u32 attr, int channel, long *val)
{
	int ret;
	u64 value;
	const struct scmi_sensor_info *sensor;
	struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev);
	const struct scmi_handle *h = scmi_sensors->handle;

	sensor = *(scmi_sensors->info[type] + channel);
	ret = h->sensor_ops->reading_get(h, sensor->id, &value);
	if (ret)
		return ret;

	ret = scmi_hwmon_scale(sensor, &value);
	if (!ret)
		*val = value;

	return ret;
}

static int
scmi_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type,
		       u32 attr, int channel, const char **str)
{
	const struct scmi_sensor_info *sensor;
	struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev);

	sensor = *(scmi_sensors->info[type] + channel);
	*str = sensor->name;

	return 0;
}

static umode_t
scmi_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_types type,
		      u32 attr, int channel)
{
	const struct scmi_sensor_info *sensor;
	const struct scmi_sensors *scmi_sensors = drvdata;

	sensor = *(scmi_sensors->info[type] + channel);
	if (sensor)
		return 0444;

	return 0;
}

static const struct hwmon_ops scmi_hwmon_ops = {
	.is_visible = scmi_hwmon_is_visible,
	.read = scmi_hwmon_read,
	.read_string = scmi_hwmon_read_string,
};

static struct hwmon_chip_info scmi_chip_info = {
	.ops = &scmi_hwmon_ops,
	.info = NULL,
};

static int scmi_hwmon_add_chan_info(struct hwmon_channel_info *scmi_hwmon_chan,
				    struct device *dev, int num,
				    enum hwmon_sensor_types type, u32 config)
{
	int i;
	u32 *cfg = devm_kcalloc(dev, num + 1, sizeof(*cfg), GFP_KERNEL);

	if (!cfg)
		return -ENOMEM;

	scmi_hwmon_chan->type = type;
	scmi_hwmon_chan->config = cfg;
	for (i = 0; i < num; i++, cfg++)
		*cfg = config;

	return 0;
}

static enum hwmon_sensor_types scmi_types[] = {
	[TEMPERATURE_C] = hwmon_temp,
	[VOLTAGE] = hwmon_in,
	[CURRENT] = hwmon_curr,
	[POWER] = hwmon_power,
	[ENERGY] = hwmon_energy,
};

static u32 hwmon_attributes[] = {
	[hwmon_chip] = HWMON_C_REGISTER_TZ,
	[hwmon_temp] = HWMON_T_INPUT | HWMON_T_LABEL,
	[hwmon_in] = HWMON_I_INPUT | HWMON_I_LABEL,
	[hwmon_curr] = HWMON_C_INPUT | HWMON_C_LABEL,
	[hwmon_power] = HWMON_P_INPUT | HWMON_P_LABEL,
	[hwmon_energy] = HWMON_E_INPUT | HWMON_E_LABEL,
};

static int scmi_hwmon_probe(struct scmi_device *sdev)
{
	int i, idx;
	u16 nr_sensors;
	enum hwmon_sensor_types type;
	struct scmi_sensors *scmi_sensors;
	const struct scmi_sensor_info *sensor;
	int nr_count[hwmon_max] = {0}, nr_types = 0;
	const struct hwmon_chip_info *chip_info;
	struct device *hwdev, *dev = &sdev->dev;
	struct hwmon_channel_info *scmi_hwmon_chan;
	const struct hwmon_channel_info **ptr_scmi_ci;
	const struct scmi_handle *handle = sdev->handle;

	if (!handle || !handle->sensor_ops)
		return -ENODEV;

	nr_sensors = handle->sensor_ops->count_get(handle);
	if (!nr_sensors)
		return -EIO;

	scmi_sensors = devm_kzalloc(dev, sizeof(*scmi_sensors), GFP_KERNEL);
	if (!scmi_sensors)
		return -ENOMEM;

	scmi_sensors->handle = handle;

	for (i = 0; i < nr_sensors; i++) {
		sensor = handle->sensor_ops->info_get(handle, i);
		if (!sensor)
			return -EINVAL;

		switch (sensor->type) {
		case TEMPERATURE_C:
		case VOLTAGE:
		case CURRENT:
		case POWER:
		case ENERGY:
			type = scmi_types[sensor->type];
			if (!nr_count[type])
				nr_types++;
			nr_count[type]++;
			break;
		}
	}

	if (nr_count[hwmon_temp])
		nr_count[hwmon_chip]++, nr_types++;

	scmi_hwmon_chan = devm_kcalloc(dev, nr_types, sizeof(*scmi_hwmon_chan),
				       GFP_KERNEL);
	if (!scmi_hwmon_chan)
		return -ENOMEM;

	ptr_scmi_ci = devm_kcalloc(dev, nr_types + 1, sizeof(*ptr_scmi_ci),
				   GFP_KERNEL);
	if (!ptr_scmi_ci)
		return -ENOMEM;

	scmi_chip_info.info = ptr_scmi_ci;
	chip_info = &scmi_chip_info;

	for (type = 0; type < hwmon_max; type++) {
		if (!nr_count[type])
			continue;

		scmi_hwmon_add_chan_info(scmi_hwmon_chan, dev, nr_count[type],
					 type, hwmon_attributes[type]);
		*ptr_scmi_ci++ = scmi_hwmon_chan++;

		scmi_sensors->info[type] =
			devm_kcalloc(dev, nr_count[type],
				     sizeof(*scmi_sensors->info), GFP_KERNEL);
		if (!scmi_sensors->info[type])
			return -ENOMEM;
	}

	for (i = nr_sensors - 1; i >= 0 ; i--) {
		sensor = handle->sensor_ops->info_get(handle, i);
		if (!sensor)
			continue;

		switch (sensor->type) {
		case TEMPERATURE_C:
		case VOLTAGE:
		case CURRENT:
		case POWER:
		case ENERGY:
			type = scmi_types[sensor->type];
			idx = --nr_count[type];
			*(scmi_sensors->info[type] + idx) = sensor;
			break;
		}
	}

	hwdev = devm_hwmon_device_register_with_info(dev, "scmi_sensors",
						     scmi_sensors, chip_info,
						     NULL);

	return PTR_ERR_OR_ZERO(hwdev);
}

static const struct scmi_device_id scmi_id_table[] = {
	{ SCMI_PROTOCOL_SENSOR },
	{ },
};
MODULE_DEVICE_TABLE(scmi, scmi_id_table);

static struct scmi_driver scmi_hwmon_drv = {
	.name		= "scmi-hwmon",
	.probe		= scmi_hwmon_probe,
	.id_table	= scmi_id_table,
};
module_scmi_driver(scmi_hwmon_drv);

MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
MODULE_DESCRIPTION("ARM SCMI HWMON interface driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
b23688ae SH	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* System Control and Management Interface(SCMI) based hwmon sensor driver
	4	*
	5	* Copyright (C) 2018 ARM Ltd.
	6	* Sudeep Holla <sudeep.holla@arm.com>
	7	*/
	8
	9	#include <linux/hwmon.h>
	10	#include <linux/module.h>
	11	#include <linux/scmi_protocol.h>
	12	#include <linux/slab.h>
	13	#include <linux/sysfs.h>
	14	#include <linux/thermal.h>
	15
	16	struct scmi_sensors {
	17	const struct scmi_handle *handle;
	18	const struct scmi_sensor_info **info[hwmon_max];
	19	};
	20
ac778e62 FF	21	static inline u64 __pow10(u8 x)
	22	{
	23	u64 r = 1;
	24
	25	while (x--)
	26	r *= 10;
	27
	28	return r;
	29	}
	30
	31	static int scmi_hwmon_scale(const struct scmi_sensor_info sensor, u64 value)
	32	{
	33	s8 scale = sensor->scale;
	34	u64 f;
	35
	36	switch (sensor->type) {
	37	case TEMPERATURE_C:
	38	case VOLTAGE:
	39	case CURRENT:
	40	scale += 3;
	41	break;
	42	case POWER:
	43	case ENERGY:
	44	scale += 6;
	45	break;
	46	default:
	47	break;
	48	}
	49
	50	if (scale == 0)
	51	return 0;
	52
	53	if (abs(scale) > 19)
	54	return -E2BIG;
	55
	56	f = __pow10(abs(scale));
	57	if (scale > 0)
	58	value = f;
	59	else
	60	value = div64_u64(value, f);
	61
	62	return 0;
	63	}
	64
b23688ae SH	65	static int scmi_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
	66	u32 attr, int channel, long *val)
	67	{
	68	int ret;
	69	u64 value;
	70	const struct scmi_sensor_info *sensor;
	71	struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev);
	72	const struct scmi_handle *h = scmi_sensors->handle;
	73
	74	sensor = *(scmi_sensors->info[type] + channel);
6a55331c	75	ret = h->sensor_ops->reading_get(h, sensor->id, &value);
ac778e62 FF	76	if (ret)
	77	return ret;
	78
	79	ret = scmi_hwmon_scale(sensor, &value);
b23688ae SH	80	if (!ret)
	81	*val = value;
	82
	83	return ret;
	84	}
	85
	86	static int
	87	scmi_hwmon_read_string(struct device *dev, enum hwmon_sensor_types type,
	88	u32 attr, int channel, const char **str)
	89	{
	90	const struct scmi_sensor_info *sensor;
	91	struct scmi_sensors *scmi_sensors = dev_get_drvdata(dev);
	92
	93	sensor = *(scmi_sensors->info[type] + channel);
	94	*str = sensor->name;
	95
	96	return 0;
	97	}
	98
	99	static umode_t
	100	scmi_hwmon_is_visible(const void *drvdata, enum hwmon_sensor_types type,
	101	u32 attr, int channel)
	102	{
	103	const struct scmi_sensor_info *sensor;
	104	const struct scmi_sensors *scmi_sensors = drvdata;
	105
	106	sensor = *(scmi_sensors->info[type] + channel);
a31796c3	107	if (sensor)
626c4a06	108	return 0444;
b23688ae SH	109
	110	return 0;
	111	}
	112
	113	static const struct hwmon_ops scmi_hwmon_ops = {
	114	.is_visible = scmi_hwmon_is_visible,
	115	.read = scmi_hwmon_read,
	116	.read_string = scmi_hwmon_read_string,
	117	};
	118
	119	static struct hwmon_chip_info scmi_chip_info = {
	120	.ops = &scmi_hwmon_ops,
	121	.info = NULL,
	122	};
	123
	124	static int scmi_hwmon_add_chan_info(struct hwmon_channel_info *scmi_hwmon_chan,
	125	struct device *dev, int num,
	126	enum hwmon_sensor_types type, u32 config)
	127	{
	128	int i;
	129	u32 cfg = devm_kcalloc(dev, num + 1, sizeof(cfg), GFP_KERNEL);
	130
	131	if (!cfg)
	132	return -ENOMEM;
	133
	134	scmi_hwmon_chan->type = type;
	135	scmi_hwmon_chan->config = cfg;
	136	for (i = 0; i < num; i++, cfg++)
	137	*cfg = config;
	138
	139	return 0;
	140	}
	141
	142	static enum hwmon_sensor_types scmi_types[] = {
	143	[TEMPERATURE_C] = hwmon_temp,
	144	[VOLTAGE] = hwmon_in,
	145	[CURRENT] = hwmon_curr,
	146	[POWER] = hwmon_power,
	147	[ENERGY] = hwmon_energy,
	148	};
	149
	150	static u32 hwmon_attributes[] = {
	151	[hwmon_chip] = HWMON_C_REGISTER_TZ,
	152	[hwmon_temp] = HWMON_T_INPUT \| HWMON_T_LABEL,
	153	[hwmon_in] = HWMON_I_INPUT \| HWMON_I_LABEL,
	154	[hwmon_curr] = HWMON_C_INPUT \| HWMON_C_LABEL,
	155	[hwmon_power] = HWMON_P_INPUT \| HWMON_P_LABEL,
	156	[hwmon_energy] = HWMON_E_INPUT \| HWMON_E_LABEL,
	157	};
	158
	159	static int scmi_hwmon_probe(struct scmi_device *sdev)
	160	{
	161	int i, idx;
	162	u16 nr_sensors;
	163	enum hwmon_sensor_types type;
	164	struct scmi_sensors *scmi_sensors;
	165	const struct scmi_sensor_info *sensor;
	166	int nr_count[hwmon_max] = {0}, nr_types = 0;
	167	const struct hwmon_chip_info *chip_info;
	168	struct device hwdev, dev = &sdev->dev;
	169	struct hwmon_channel_info *scmi_hwmon_chan;
	170	const struct hwmon_channel_info **ptr_scmi_ci;
	171	const struct scmi_handle *handle = sdev->handle;
	172
173	if (!handle \|\| !handle->sensor_ops)
174	return -ENODEV;
175
176	nr_sensors = handle->sensor_ops->count_get(handle);
177	if (!nr_sensors)
178	return -EIO;
179
180	scmi_sensors = devm_kzalloc(dev, sizeof(*scmi_sensors), GFP_KERNEL);
181	if (!scmi_sensors)
182	return -ENOMEM;
183
184	scmi_sensors->handle = handle;
185
186	for (i = 0; i < nr_sensors; i++) {
187	sensor = handle->sensor_ops->info_get(handle, i);
188	if (!sensor)
c09880ce	189	return -EINVAL;
b23688ae SH	190
	191	switch (sensor->type) {
	192	case TEMPERATURE_C:
	193	case VOLTAGE:
	194	case CURRENT:
	195	case POWER:
	196	case ENERGY:
	197	type = scmi_types[sensor->type];
	198	if (!nr_count[type])
	199	nr_types++;
	200	nr_count[type]++;
	201	break;
	202	}
	203	}
	204
	205	if (nr_count[hwmon_temp])
	206	nr_count[hwmon_chip]++, nr_types++;
	207
	208	scmi_hwmon_chan = devm_kcalloc(dev, nr_types, sizeof(*scmi_hwmon_chan),
	209	GFP_KERNEL);
	210	if (!scmi_hwmon_chan)
	211	return -ENOMEM;
	212
	213	ptr_scmi_ci = devm_kcalloc(dev, nr_types + 1, sizeof(*ptr_scmi_ci),
	214	GFP_KERNEL);
	215	if (!ptr_scmi_ci)
	216	return -ENOMEM;
	217
	218	scmi_chip_info.info = ptr_scmi_ci;
	219	chip_info = &scmi_chip_info;
	220
f18a36cf SH	221	for (type = 0; type < hwmon_max; type++) {
	222	if (!nr_count[type])
	223	continue;
	224
b23688ae SH	225	scmi_hwmon_add_chan_info(scmi_hwmon_chan, dev, nr_count[type],
	226	type, hwmon_attributes[type]);
	227	*ptr_scmi_ci++ = scmi_hwmon_chan++;
	228
	229	scmi_sensors->info[type] =
	230	devm_kcalloc(dev, nr_count[type],
	231	sizeof(*scmi_sensors->info), GFP_KERNEL);
	232	if (!scmi_sensors->info[type])
	233	return -ENOMEM;
	234	}
	235
	236	for (i = nr_sensors - 1; i >= 0 ; i--) {
	237	sensor = handle->sensor_ops->info_get(handle, i);
	238	if (!sensor)
	239	continue;
	240
	241	switch (sensor->type) {
	242	case TEMPERATURE_C:
	243	case VOLTAGE:
	244	case CURRENT:
	245	case POWER:
	246	case ENERGY:
	247	type = scmi_types[sensor->type];
	248	idx = --nr_count[type];
	249	*(scmi_sensors->info[type] + idx) = sensor;
	250	break;
	251	}
	252	}
	253
	254	hwdev = devm_hwmon_device_register_with_info(dev, "scmi_sensors",
	255	scmi_sensors, chip_info,
	256	NULL);
	257
	258	return PTR_ERR_OR_ZERO(hwdev);
	259	}
	260
	261	static const struct scmi_device_id scmi_id_table[] = {
	262	{ SCMI_PROTOCOL_SENSOR },
	263	{ },
	264	};
	265	MODULE_DEVICE_TABLE(scmi, scmi_id_table);
	266
	267	static struct scmi_driver scmi_hwmon_drv = {
	268	.name = "scmi-hwmon",
	269	.probe = scmi_hwmon_probe,
	270	.id_table = scmi_id_table,
	271	};
	272	module_scmi_driver(scmi_hwmon_drv);
	273
	274	MODULE_AUTHOR("Sudeep Holla <sudeep.holla@arm.com>");
	275	MODULE_DESCRIPTION("ARM SCMI HWMON interface driver");
	276	MODULE_LICENSE("GPL v2");