[mirror_ubuntu-hirsute-kernel.git] / drivers / hwmon / scpi-hwmon.c

// SPDX-License-Identifier: GPL-2.0
/*
 * System Control and Power Interface(SCPI) based hwmon sensor driver
 *
 * Copyright (C) 2015 ARM Ltd.
 * Punit Agrawal <punit.agrawal@arm.com>
 */

#include <linux/hwmon.h>
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/scpi_protocol.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/thermal.h>

struct sensor_data {
	unsigned int scale;
	struct scpi_sensor_info info;
	struct device_attribute dev_attr_input;
	struct device_attribute dev_attr_label;
	char input[20];
	char label[20];
};

struct scpi_thermal_zone {
	int sensor_id;
	struct scpi_sensors *scpi_sensors;
};

struct scpi_sensors {
	struct scpi_ops *scpi_ops;
	struct sensor_data *data;
	struct list_head thermal_zones;
	struct attribute **attrs;
	struct attribute_group group;
	const struct attribute_group *groups[2];
};

static const u32 gxbb_scpi_scale[] = {
	[TEMPERATURE]	= 1,		/* (celsius)		*/
	[VOLTAGE]	= 1000,		/* (millivolts)		*/
	[CURRENT]	= 1000,		/* (milliamperes)	*/
	[POWER]		= 1000000,	/* (microwatts)		*/
	[ENERGY]	= 1000000,	/* (microjoules)	*/
};

static const u32 scpi_scale[] = {
	[TEMPERATURE]	= 1000,		/* (millicelsius)	*/
	[VOLTAGE]	= 1000,		/* (millivolts)		*/
	[CURRENT]	= 1000,		/* (milliamperes)	*/
	[POWER]		= 1000000,	/* (microwatts)		*/
	[ENERGY]	= 1000000,	/* (microjoules)	*/
};

static void scpi_scale_reading(u64 *value, struct sensor_data *sensor)
{
	if (scpi_scale[sensor->info.class] != sensor->scale) {
		*value *= scpi_scale[sensor->info.class];
		do_div(*value, sensor->scale);
	}
}

static int scpi_read_temp(void *dev, int *temp)
{
	struct scpi_thermal_zone *zone = dev;
	struct scpi_sensors *scpi_sensors = zone->scpi_sensors;
	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
	struct sensor_data *sensor = &scpi_sensors->data[zone->sensor_id];
	u64 value;
	int ret;

	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
	if (ret)
		return ret;

	scpi_scale_reading(&value, sensor);

	*temp = value;
	return 0;
}

/* hwmon callback functions */
static ssize_t
scpi_show_sensor(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct scpi_sensors *scpi_sensors = dev_get_drvdata(dev);
	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
	struct sensor_data *sensor;
	u64 value;
	int ret;

	sensor = container_of(attr, struct sensor_data, dev_attr_input);

	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
	if (ret)
		return ret;

	scpi_scale_reading(&value, sensor);

	return sprintf(buf, "%llu\n", value);
}

static ssize_t
scpi_show_label(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct sensor_data *sensor;

	sensor = container_of(attr, struct sensor_data, dev_attr_label);

	return sprintf(buf, "%s\n", sensor->info.name);
}

static const struct thermal_zone_of_device_ops scpi_sensor_ops = {
	.get_temp = scpi_read_temp,
};

static const struct of_device_id scpi_of_match[] = {
	{.compatible = "arm,scpi-sensors", .data = &scpi_scale},
	{.compatible = "amlogic,meson-gxbb-scpi-sensors", .data = &gxbb_scpi_scale},
	{},
};
MODULE_DEVICE_TABLE(of, scpi_of_match);

static int scpi_hwmon_probe(struct platform_device *pdev)
{
	u16 nr_sensors, i;
	const u32 *scale;
	int num_temp = 0, num_volt = 0, num_current = 0, num_power = 0;
	int num_energy = 0;
	struct scpi_ops *scpi_ops;
	struct device *hwdev, *dev = &pdev->dev;
	struct scpi_sensors *scpi_sensors;
	const struct of_device_id *of_id;
	int idx, ret;

	scpi_ops = get_scpi_ops();
	if (!scpi_ops)
		return -EPROBE_DEFER;

	ret = scpi_ops->sensor_get_capability(&nr_sensors);
	if (ret)
		return ret;

	if (!nr_sensors)
		return -ENODEV;

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

	scpi_sensors->data = devm_kcalloc(dev, nr_sensors,
				   sizeof(*scpi_sensors->data), GFP_KERNEL);
	if (!scpi_sensors->data)
		return -ENOMEM;

	scpi_sensors->attrs = devm_kcalloc(dev, (nr_sensors * 2) + 1,
				   sizeof(*scpi_sensors->attrs), GFP_KERNEL);
	if (!scpi_sensors->attrs)
		return -ENOMEM;

	scpi_sensors->scpi_ops = scpi_ops;

	of_id = of_match_device(scpi_of_match, &pdev->dev);
	if (!of_id) {
		dev_err(&pdev->dev, "Unable to initialize scpi-hwmon data\n");
		return -ENODEV;
	}
	scale = of_id->data;

	for (i = 0, idx = 0; i < nr_sensors; i++) {
		struct sensor_data *sensor = &scpi_sensors->data[idx];

		ret = scpi_ops->sensor_get_info(i, &sensor->info);
		if (ret)
			return ret;

		switch (sensor->info.class) {
		case TEMPERATURE:
			snprintf(sensor->input, sizeof(sensor->input),
				 "temp%d_input", num_temp + 1);
			snprintf(sensor->label, sizeof(sensor->input),
				 "temp%d_label", num_temp + 1);
			num_temp++;
			break;
		case VOLTAGE:
			snprintf(sensor->input, sizeof(sensor->input),
				 "in%d_input", num_volt);
			snprintf(sensor->label, sizeof(sensor->input),
				 "in%d_label", num_volt);
			num_volt++;
			break;
		case CURRENT:
			snprintf(sensor->input, sizeof(sensor->input),
				 "curr%d_input", num_current + 1);
			snprintf(sensor->label, sizeof(sensor->input),
				 "curr%d_label", num_current + 1);
			num_current++;
			break;
		case POWER:
			snprintf(sensor->input, sizeof(sensor->input),
				 "power%d_input", num_power + 1);
			snprintf(sensor->label, sizeof(sensor->input),
				 "power%d_label", num_power + 1);
			num_power++;
			break;
		case ENERGY:
			snprintf(sensor->input, sizeof(sensor->input),
				 "energy%d_input", num_energy + 1);
			snprintf(sensor->label, sizeof(sensor->input),
				 "energy%d_label", num_energy + 1);
			num_energy++;
			break;
		default:
			continue;
		}

		sensor->scale = scale[sensor->info.class];

		sensor->dev_attr_input.attr.mode = 0444;
		sensor->dev_attr_input.show = scpi_show_sensor;
		sensor->dev_attr_input.attr.name = sensor->input;

		sensor->dev_attr_label.attr.mode = 0444;
		sensor->dev_attr_label.show = scpi_show_label;
		sensor->dev_attr_label.attr.name = sensor->label;

		scpi_sensors->attrs[idx << 1] = &sensor->dev_attr_input.attr;
		scpi_sensors->attrs[(idx << 1) + 1] = &sensor->dev_attr_label.attr;

		sysfs_attr_init(scpi_sensors->attrs[idx << 1]);
		sysfs_attr_init(scpi_sensors->attrs[(idx << 1) + 1]);
		idx++;
	}

	scpi_sensors->group.attrs = scpi_sensors->attrs;
	scpi_sensors->groups[0] = &scpi_sensors->group;

	platform_set_drvdata(pdev, scpi_sensors);

	hwdev = devm_hwmon_device_register_with_groups(dev,
			"scpi_sensors", scpi_sensors, scpi_sensors->groups);

	if (IS_ERR(hwdev))
		return PTR_ERR(hwdev);

	/*
	 * Register the temperature sensors with the thermal framework
	 * to allow their usage in setting up the thermal zones from
	 * device tree.
	 *
	 * NOTE: Not all temperature sensors maybe used for thermal
	 * control
	 */
	INIT_LIST_HEAD(&scpi_sensors->thermal_zones);
	for (i = 0; i < nr_sensors; i++) {
		struct sensor_data *sensor = &scpi_sensors->data[i];
		struct thermal_zone_device *z;
		struct scpi_thermal_zone *zone;

		if (sensor->info.class != TEMPERATURE)
			continue;

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

		zone->sensor_id = i;
		zone->scpi_sensors = scpi_sensors;
		z = devm_thermal_zone_of_sensor_register(dev,
							 sensor->info.sensor_id,
							 zone,
							 &scpi_sensor_ops);
		/*
		 * The call to thermal_zone_of_sensor_register returns
		 * an error for sensors that are not associated with
		 * any thermal zones or if the thermal subsystem is
		 * not configured.
		 */
		if (IS_ERR(z))
			devm_kfree(dev, zone);
	}

	return 0;
}

static struct platform_driver scpi_hwmon_platdrv = {
	.driver = {
		.name	= "scpi-hwmon",
		.of_match_table = scpi_of_match,
	},
	.probe		= scpi_hwmon_probe,
};
module_platform_driver(scpi_hwmon_platdrv);

MODULE_AUTHOR("Punit Agrawal <punit.agrawal@arm.com>");
MODULE_DESCRIPTION("ARM SCPI HWMON interface driver");
MODULE_LICENSE("GPL v2");
Commit	Line	Data
23297edb	1	// SPDX-License-Identifier: GPL-2.0
ea98b29a PA	2	/*
	3	* System Control and Power Interface(SCPI) based hwmon sensor driver
	4	*
	5	* Copyright (C) 2015 ARM Ltd.
	6	* Punit Agrawal <punit.agrawal@arm.com>
ea98b29a PA	7	*/
	8
	9	#include <linux/hwmon.h>
	10	#include <linux/module.h>
ccc9b826	11	#include <linux/of_device.h>
ea98b29a PA	12	#include <linux/platform_device.h>
	13	#include <linux/scpi_protocol.h>
	14	#include <linux/slab.h>
	15	#include <linux/sysfs.h>
68acc77a	16	#include <linux/thermal.h>
ea98b29a PA	17
ea98b29a PA	18	struct sensor_data {
ccc9b826	19	unsigned int scale;
ea98b29a PA	20	struct scpi_sensor_info info;
	21	struct device_attribute dev_attr_input;
	22	struct device_attribute dev_attr_label;
	23	char input[20];
	24	char label[20];
	25	};
	26
68acc77a	27	struct scpi_thermal_zone {
68acc77a PA	28	int sensor_id;
68acc77a PA	29	struct scpi_sensors *scpi_sensors;
68acc77a PA	30	};
68acc77a PA	31
ea98b29a PA	32	struct scpi_sensors {
	33	struct scpi_ops *scpi_ops;
	34	struct sensor_data *data;
68acc77a	35	struct list_head thermal_zones;
ea98b29a PA	36	struct attribute **attrs;
	37	struct attribute_group group;
	38	const struct attribute_group *groups[2];
	39	};
	40
ccc9b826 CC	41	static const u32 gxbb_scpi_scale[] = {
	42	[TEMPERATURE] = 1, /* (celsius) */
	43	[VOLTAGE] = 1000, /* (millivolts) */
	44	[CURRENT] = 1000, /* (milliamperes) */
	45	[POWER] = 1000000, /* (microwatts) */
	46	[ENERGY] = 1000000, /* (microjoules) */
	47	};
	48
	49	static const u32 scpi_scale[] = {
	50	[TEMPERATURE] = 1000, /* (millicelsius) */
	51	[VOLTAGE] = 1000, /* (millivolts) */
	52	[CURRENT] = 1000, /* (milliamperes) */
	53	[POWER] = 1000000, /* (microwatts) */
	54	[ENERGY] = 1000000, /* (microjoules) */
	55	};
	56
	57	static void scpi_scale_reading(u64 value, struct sensor_data sensor)
	58	{
	59	if (scpi_scale[sensor->info.class] != sensor->scale) {
	60	value = scpi_scale[sensor->info.class];
	61	do_div(*value, sensor->scale);
	62	}
	63	}
	64
68acc77a PA	65	static int scpi_read_temp(void dev, int temp)
	66	{
	67	struct scpi_thermal_zone *zone = dev;
	68	struct scpi_sensors *scpi_sensors = zone->scpi_sensors;
	69	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
	70	struct sensor_data *sensor = &scpi_sensors->data[zone->sensor_id];
2e874159	71	u64 value;
68acc77a PA	72	int ret;
	73
	74	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
	75	if (ret)
	76	return ret;
	77
ccc9b826 CC	78	scpi_scale_reading(&value, sensor);
ccc9b826 CC	79
68acc77a PA	80	*temp = value;
	81	return 0;
	82	}
	83
ea98b29a PA	84	/* hwmon callback functions */
	85	static ssize_t
	86	scpi_show_sensor(struct device dev, struct device_attribute attr, char *buf)
	87	{
	88	struct scpi_sensors *scpi_sensors = dev_get_drvdata(dev);
	89	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
	90	struct sensor_data *sensor;
2e874159	91	u64 value;
ea98b29a PA	92	int ret;
	93
	94	sensor = container_of(attr, struct sensor_data, dev_attr_input);
	95
	96	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
	97	if (ret)
	98	return ret;
	99
ccc9b826 CC	100	scpi_scale_reading(&value, sensor);
ccc9b826 CC	101
2e874159	102	return sprintf(buf, "%llu\n", value);
ea98b29a PA	103	}
	104
	105	static ssize_t
	106	scpi_show_label(struct device dev, struct device_attribute attr, char *buf)
	107	{
	108	struct sensor_data *sensor;
	109
	110	sensor = container_of(attr, struct sensor_data, dev_attr_label);
	111
	112	return sprintf(buf, "%s\n", sensor->info.name);
	113	}
	114
778fb961	115	static const struct thermal_zone_of_device_ops scpi_sensor_ops = {
68acc77a PA	116	.get_temp = scpi_read_temp,
	117	};
	118
ccc9b826 CC	119	static const struct of_device_id scpi_of_match[] = {
	120	{.compatible = "arm,scpi-sensors", .data = &scpi_scale},
	121	{.compatible = "amlogic,meson-gxbb-scpi-sensors", .data = &gxbb_scpi_scale},
	122	{},
	123	};
	124	MODULE_DEVICE_TABLE(of, scpi_of_match);
	125
ea98b29a PA	126	static int scpi_hwmon_probe(struct platform_device *pdev)
	127	{
	128	u16 nr_sensors, i;
ccc9b826	129	const u32 *scale;
ea98b29a	130	int num_temp = 0, num_volt = 0, num_current = 0, num_power = 0;
fb3b07ef	131	int num_energy = 0;
ea98b29a PA	132	struct scpi_ops *scpi_ops;
	133	struct device hwdev, dev = &pdev->dev;
	134	struct scpi_sensors *scpi_sensors;
ccc9b826	135	const struct of_device_id *of_id;
d7817ff2	136	int idx, ret;
ea98b29a PA	137
	138	scpi_ops = get_scpi_ops();
	139	if (!scpi_ops)
	140	return -EPROBE_DEFER;
	141
	142	ret = scpi_ops->sensor_get_capability(&nr_sensors);
	143	if (ret)
	144	return ret;
	145
	146	if (!nr_sensors)
	147	return -ENODEV;
	148
	149	scpi_sensors = devm_kzalloc(dev, sizeof(*scpi_sensors), GFP_KERNEL);
	150	if (!scpi_sensors)
	151	return -ENOMEM;
	152
	153	scpi_sensors->data = devm_kcalloc(dev, nr_sensors,
	154	sizeof(*scpi_sensors->data), GFP_KERNEL);
	155	if (!scpi_sensors->data)
	156	return -ENOMEM;
	157
	158	scpi_sensors->attrs = devm_kcalloc(dev, (nr_sensors * 2) + 1,
	159	sizeof(*scpi_sensors->attrs), GFP_KERNEL);
	160	if (!scpi_sensors->attrs)
	161	return -ENOMEM;
	162
	163	scpi_sensors->scpi_ops = scpi_ops;
	164
ccc9b826 CC	165	of_id = of_match_device(scpi_of_match, &pdev->dev);
	166	if (!of_id) {
	167	dev_err(&pdev->dev, "Unable to initialize scpi-hwmon data\n");
	168	return -ENODEV;
	169	}
	170	scale = of_id->data;
	171
cef03d7e SH	172	for (i = 0, idx = 0; i < nr_sensors; i++) {
cef03d7e SH	173	struct sensor_data *sensor = &scpi_sensors->data[idx];
ea98b29a PA	174
	175	ret = scpi_ops->sensor_get_info(i, &sensor->info);
	176	if (ret)
	177	return ret;
	178
	179	switch (sensor->info.class) {
	180	case TEMPERATURE:
	181	snprintf(sensor->input, sizeof(sensor->input),
	182	"temp%d_input", num_temp + 1);
	183	snprintf(sensor->label, sizeof(sensor->input),
	184	"temp%d_label", num_temp + 1);
	185	num_temp++;
	186	break;
	187	case VOLTAGE:
	188	snprintf(sensor->input, sizeof(sensor->input),
	189	"in%d_input", num_volt);
	190	snprintf(sensor->label, sizeof(sensor->input),
	191	"in%d_label", num_volt);
	192	num_volt++;
	193	break;
	194	case CURRENT:
	195	snprintf(sensor->input, sizeof(sensor->input),
	196	"curr%d_input", num_current + 1);
	197	snprintf(sensor->label, sizeof(sensor->input),
	198	"curr%d_label", num_current + 1);
	199	num_current++;
	200	break;
	201	case POWER:
	202	snprintf(sensor->input, sizeof(sensor->input),
	203	"power%d_input", num_power + 1);
	204	snprintf(sensor->label, sizeof(sensor->input),
	205	"power%d_label", num_power + 1);
	206	num_power++;
	207	break;
fb3b07ef SH	208	case ENERGY:
	209	snprintf(sensor->input, sizeof(sensor->input),
	210	"energy%d_input", num_energy + 1);
	211	snprintf(sensor->label, sizeof(sensor->input),
	212	"energy%d_label", num_energy + 1);
	213	num_energy++;
	214	break;
ea98b29a	215	default:
cef03d7e	216	continue;
ea98b29a PA	217	}
ea98b29a PA	218
ccc9b826 CC	219	sensor->scale = scale[sensor->info.class];
ccc9b826 CC	220
6a0785aa	221	sensor->dev_attr_input.attr.mode = 0444;
ea98b29a PA	222	sensor->dev_attr_input.show = scpi_show_sensor;
	223	sensor->dev_attr_input.attr.name = sensor->input;
	224
6a0785aa	225	sensor->dev_attr_label.attr.mode = 0444;
ea98b29a PA	226	sensor->dev_attr_label.show = scpi_show_label;
	227	sensor->dev_attr_label.attr.name = sensor->label;
	228
cef03d7e SH	229	scpi_sensors->attrs[idx << 1] = &sensor->dev_attr_input.attr;
cef03d7e SH	230	scpi_sensors->attrs[(idx << 1) + 1] = &sensor->dev_attr_label.attr;
ea98b29a	231
cef03d7e SH	232	sysfs_attr_init(scpi_sensors->attrs[idx << 1]);
	233	sysfs_attr_init(scpi_sensors->attrs[(idx << 1) + 1]);
	234	idx++;
ea98b29a PA	235	}
	236
	237	scpi_sensors->group.attrs = scpi_sensors->attrs;
	238	scpi_sensors->groups[0] = &scpi_sensors->group;
	239
68acc77a PA	240	platform_set_drvdata(pdev, scpi_sensors);
68acc77a PA	241
ea98b29a PA	242	hwdev = devm_hwmon_device_register_with_groups(dev,
	243	"scpi_sensors", scpi_sensors, scpi_sensors->groups);
	244
68acc77a PA	245	if (IS_ERR(hwdev))
	246	return PTR_ERR(hwdev);
	247
	248	/*
	249	* Register the temperature sensors with the thermal framework
	250	* to allow their usage in setting up the thermal zones from
	251	* device tree.
	252	*
	253	* NOTE: Not all temperature sensors maybe used for thermal
	254	* control
	255	*/
	256	INIT_LIST_HEAD(&scpi_sensors->thermal_zones);
	257	for (i = 0; i < nr_sensors; i++) {
	258	struct sensor_data *sensor = &scpi_sensors->data[i];
d7817ff2	259	struct thermal_zone_device *z;
68acc77a PA	260	struct scpi_thermal_zone *zone;
	261
	262	if (sensor->info.class != TEMPERATURE)
	263	continue;
	264
	265	zone = devm_kzalloc(dev, sizeof(*zone), GFP_KERNEL);
d7817ff2 EV	266	if (!zone)
d7817ff2 EV	267	return -ENOMEM;
68acc77a PA	268
	269	zone->sensor_id = i;
	270	zone->scpi_sensors = scpi_sensors;
d7817ff2 EV	271	z = devm_thermal_zone_of_sensor_register(dev,
	272	sensor->info.sensor_id,
	273	zone,
	274	&scpi_sensor_ops);
68acc77a PA	275	/*
	276	* The call to thermal_zone_of_sensor_register returns
	277	* an error for sensors that are not associated with
	278	* any thermal zones or if the thermal subsystem is
	279	* not configured.
	280	*/
3045b5d6	281	if (IS_ERR(z))
68acc77a	282	devm_kfree(dev, zone);
68acc77a PA	283	}
68acc77a PA	284
68acc77a	285	return 0;
ea98b29a PA	286	}
ea98b29a PA	287
ea98b29a PA	288	static struct platform_driver scpi_hwmon_platdrv = {
	289	.driver = {
	290	.name = "scpi-hwmon",
ea98b29a PA	291	.of_match_table = scpi_of_match,
	292	},
	293	.probe = scpi_hwmon_probe,
	294	};
	295	module_platform_driver(scpi_hwmon_platdrv);
	296
	297	MODULE_AUTHOR("Punit Agrawal <punit.agrawal@arm.com>");
	298	MODULE_DESCRIPTION("ARM SCPI HWMON interface driver");
	299	MODULE_LICENSE("GPL v2");