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

/*
 * System Control and Power Interface(SCPI) based hwmon sensor driver
 *
 * Copyright (C) 2015 ARM Ltd.
 * Punit Agrawal <punit.agrawal@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program is distributed "as is" WITHOUT ANY WARRANTY of any
 * kind, whether express or implied; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 */

#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 = S_IRUGO;
		sensor->dev_attr_input.show = scpi_show_sensor;
		sensor->dev_attr_input.attr.name = sensor->input;

		sensor->dev_attr_label.attr.mode = S_IRUGO;
		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);
			continue;
		}
	}

	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
ea98b29a PA	1	/*
	2	* System Control and Power Interface(SCPI) based hwmon sensor driver
	3	*
	4	* Copyright (C) 2015 ARM Ltd.
	5	* Punit Agrawal <punit.agrawal@arm.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License version 2 as
	9	* published by the Free Software Foundation.
	10	*
	11	* This program is distributed "as is" WITHOUT ANY WARRANTY of any
	12	* kind, whether express or implied; without even the implied warranty
	13	* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*/
	16
	17	#include <linux/hwmon.h>
	18	#include <linux/module.h>
ccc9b826	19	#include <linux/of_device.h>
ea98b29a PA	20	#include <linux/platform_device.h>
	21	#include <linux/scpi_protocol.h>
	22	#include <linux/slab.h>
	23	#include <linux/sysfs.h>
68acc77a	24	#include <linux/thermal.h>
ea98b29a PA	25
ea98b29a PA	26	struct sensor_data {
ccc9b826	27	unsigned int scale;
ea98b29a PA	28	struct scpi_sensor_info info;
	29	struct device_attribute dev_attr_input;
	30	struct device_attribute dev_attr_label;
	31	char input[20];
	32	char label[20];
	33	};
	34
68acc77a	35	struct scpi_thermal_zone {
68acc77a PA	36	int sensor_id;
68acc77a PA	37	struct scpi_sensors *scpi_sensors;
68acc77a PA	38	};
68acc77a PA	39
ea98b29a PA	40	struct scpi_sensors {
	41	struct scpi_ops *scpi_ops;
	42	struct sensor_data *data;
68acc77a	43	struct list_head thermal_zones;
ea98b29a PA	44	struct attribute **attrs;
	45	struct attribute_group group;
	46	const struct attribute_group *groups[2];
	47	};
	48
ccc9b826 CC	49	static const u32 gxbb_scpi_scale[] = {
	50	[TEMPERATURE] = 1, /* (celsius) */
	51	[VOLTAGE] = 1000, /* (millivolts) */
	52	[CURRENT] = 1000, /* (milliamperes) */
	53	[POWER] = 1000000, /* (microwatts) */
	54	[ENERGY] = 1000000, /* (microjoules) */
	55	};
	56
	57	static const u32 scpi_scale[] = {
	58	[TEMPERATURE] = 1000, /* (millicelsius) */
	59	[VOLTAGE] = 1000, /* (millivolts) */
	60	[CURRENT] = 1000, /* (milliamperes) */
	61	[POWER] = 1000000, /* (microwatts) */
	62	[ENERGY] = 1000000, /* (microjoules) */
	63	};
	64
	65	static void scpi_scale_reading(u64 value, struct sensor_data sensor)
	66	{
	67	if (scpi_scale[sensor->info.class] != sensor->scale) {
	68	value = scpi_scale[sensor->info.class];
	69	do_div(*value, sensor->scale);
	70	}
	71	}
	72
68acc77a PA	73	static int scpi_read_temp(void dev, int temp)
	74	{
	75	struct scpi_thermal_zone *zone = dev;
	76	struct scpi_sensors *scpi_sensors = zone->scpi_sensors;
	77	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
	78	struct sensor_data *sensor = &scpi_sensors->data[zone->sensor_id];
2e874159	79	u64 value;
68acc77a PA	80	int ret;
	81
	82	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
	83	if (ret)
	84	return ret;
	85
ccc9b826 CC	86	scpi_scale_reading(&value, sensor);
ccc9b826 CC	87
68acc77a PA	88	*temp = value;
	89	return 0;
	90	}
	91
ea98b29a PA	92	/* hwmon callback functions */
	93	static ssize_t
	94	scpi_show_sensor(struct device dev, struct device_attribute attr, char *buf)
	95	{
	96	struct scpi_sensors *scpi_sensors = dev_get_drvdata(dev);
	97	struct scpi_ops *scpi_ops = scpi_sensors->scpi_ops;
	98	struct sensor_data *sensor;
2e874159	99	u64 value;
ea98b29a PA	100	int ret;
	101
	102	sensor = container_of(attr, struct sensor_data, dev_attr_input);
	103
	104	ret = scpi_ops->sensor_get_value(sensor->info.sensor_id, &value);
	105	if (ret)
	106	return ret;
	107
ccc9b826 CC	108	scpi_scale_reading(&value, sensor);
ccc9b826 CC	109
2e874159	110	return sprintf(buf, "%llu\n", value);
ea98b29a PA	111	}
	112
	113	static ssize_t
	114	scpi_show_label(struct device dev, struct device_attribute attr, char *buf)
	115	{
	116	struct sensor_data *sensor;
	117
	118	sensor = container_of(attr, struct sensor_data, dev_attr_label);
	119
	120	return sprintf(buf, "%s\n", sensor->info.name);
	121	}
	122
778fb961	123	static const struct thermal_zone_of_device_ops scpi_sensor_ops = {
68acc77a PA	124	.get_temp = scpi_read_temp,
	125	};
	126
ccc9b826 CC	127	static const struct of_device_id scpi_of_match[] = {
	128	{.compatible = "arm,scpi-sensors", .data = &scpi_scale},
	129	{.compatible = "amlogic,meson-gxbb-scpi-sensors", .data = &gxbb_scpi_scale},
	130	{},
	131	};
	132	MODULE_DEVICE_TABLE(of, scpi_of_match);
	133
ea98b29a PA	134	static int scpi_hwmon_probe(struct platform_device *pdev)
	135	{
	136	u16 nr_sensors, i;
ccc9b826	137	const u32 *scale;
ea98b29a	138	int num_temp = 0, num_volt = 0, num_current = 0, num_power = 0;
fb3b07ef	139	int num_energy = 0;
ea98b29a PA	140	struct scpi_ops *scpi_ops;
	141	struct device hwdev, dev = &pdev->dev;
	142	struct scpi_sensors *scpi_sensors;
ccc9b826	143	const struct of_device_id *of_id;
d7817ff2	144	int idx, ret;
ea98b29a PA	145
	146	scpi_ops = get_scpi_ops();
	147	if (!scpi_ops)
	148	return -EPROBE_DEFER;
	149
	150	ret = scpi_ops->sensor_get_capability(&nr_sensors);
	151	if (ret)
	152	return ret;
	153
	154	if (!nr_sensors)
	155	return -ENODEV;
	156
	157	scpi_sensors = devm_kzalloc(dev, sizeof(*scpi_sensors), GFP_KERNEL);
	158	if (!scpi_sensors)
	159	return -ENOMEM;
	160
	161	scpi_sensors->data = devm_kcalloc(dev, nr_sensors,
	162	sizeof(*scpi_sensors->data), GFP_KERNEL);
	163	if (!scpi_sensors->data)
	164	return -ENOMEM;
	165
	166	scpi_sensors->attrs = devm_kcalloc(dev, (nr_sensors * 2) + 1,
	167	sizeof(*scpi_sensors->attrs), GFP_KERNEL);
	168	if (!scpi_sensors->attrs)
	169	return -ENOMEM;
	170
	171	scpi_sensors->scpi_ops = scpi_ops;
	172
ccc9b826 CC	173	of_id = of_match_device(scpi_of_match, &pdev->dev);
	174	if (!of_id) {
	175	dev_err(&pdev->dev, "Unable to initialize scpi-hwmon data\n");
	176	return -ENODEV;
	177	}
	178	scale = of_id->data;
	179
cef03d7e SH	180	for (i = 0, idx = 0; i < nr_sensors; i++) {
cef03d7e SH	181	struct sensor_data *sensor = &scpi_sensors->data[idx];
ea98b29a PA	182
	183	ret = scpi_ops->sensor_get_info(i, &sensor->info);
	184	if (ret)
	185	return ret;
	186
	187	switch (sensor->info.class) {
	188	case TEMPERATURE:
	189	snprintf(sensor->input, sizeof(sensor->input),
	190	"temp%d_input", num_temp + 1);
	191	snprintf(sensor->label, sizeof(sensor->input),
	192	"temp%d_label", num_temp + 1);
	193	num_temp++;
	194	break;
	195	case VOLTAGE:
	196	snprintf(sensor->input, sizeof(sensor->input),
	197	"in%d_input", num_volt);
	198	snprintf(sensor->label, sizeof(sensor->input),
	199	"in%d_label", num_volt);
	200	num_volt++;
	201	break;
	202	case CURRENT:
	203	snprintf(sensor->input, sizeof(sensor->input),
	204	"curr%d_input", num_current + 1);
	205	snprintf(sensor->label, sizeof(sensor->input),
	206	"curr%d_label", num_current + 1);
	207	num_current++;
	208	break;
	209	case POWER:
	210	snprintf(sensor->input, sizeof(sensor->input),
	211	"power%d_input", num_power + 1);
	212	snprintf(sensor->label, sizeof(sensor->input),
	213	"power%d_label", num_power + 1);
	214	num_power++;
	215	break;
fb3b07ef SH	216	case ENERGY:
	217	snprintf(sensor->input, sizeof(sensor->input),
	218	"energy%d_input", num_energy + 1);
	219	snprintf(sensor->label, sizeof(sensor->input),
	220	"energy%d_label", num_energy + 1);
	221	num_energy++;
	222	break;
ea98b29a	223	default:
cef03d7e	224	continue;
ea98b29a PA	225	}
ea98b29a PA	226
ccc9b826 CC	227	sensor->scale = scale[sensor->info.class];
ccc9b826 CC	228
ea98b29a PA	229	sensor->dev_attr_input.attr.mode = S_IRUGO;
	230	sensor->dev_attr_input.show = scpi_show_sensor;
	231	sensor->dev_attr_input.attr.name = sensor->input;
	232
	233	sensor->dev_attr_label.attr.mode = S_IRUGO;
	234	sensor->dev_attr_label.show = scpi_show_label;
	235	sensor->dev_attr_label.attr.name = sensor->label;
	236
cef03d7e SH	237	scpi_sensors->attrs[idx << 1] = &sensor->dev_attr_input.attr;
cef03d7e SH	238	scpi_sensors->attrs[(idx << 1) + 1] = &sensor->dev_attr_label.attr;
ea98b29a	239
cef03d7e SH	240	sysfs_attr_init(scpi_sensors->attrs[idx << 1]);
	241	sysfs_attr_init(scpi_sensors->attrs[(idx << 1) + 1]);
	242	idx++;
ea98b29a PA	243	}
	244
	245	scpi_sensors->group.attrs = scpi_sensors->attrs;
	246	scpi_sensors->groups[0] = &scpi_sensors->group;
	247
68acc77a PA	248	platform_set_drvdata(pdev, scpi_sensors);
68acc77a PA	249
ea98b29a PA	250	hwdev = devm_hwmon_device_register_with_groups(dev,
	251	"scpi_sensors", scpi_sensors, scpi_sensors->groups);
	252
68acc77a PA	253	if (IS_ERR(hwdev))
	254	return PTR_ERR(hwdev);
	255
	256	/*
	257	* Register the temperature sensors with the thermal framework
	258	* to allow their usage in setting up the thermal zones from
	259	* device tree.
	260	*
	261	* NOTE: Not all temperature sensors maybe used for thermal
	262	* control
	263	*/
	264	INIT_LIST_HEAD(&scpi_sensors->thermal_zones);
	265	for (i = 0; i < nr_sensors; i++) {
	266	struct sensor_data *sensor = &scpi_sensors->data[i];
d7817ff2	267	struct thermal_zone_device *z;
68acc77a PA	268	struct scpi_thermal_zone *zone;
	269
	270	if (sensor->info.class != TEMPERATURE)
	271	continue;
	272
	273	zone = devm_kzalloc(dev, sizeof(*zone), GFP_KERNEL);
d7817ff2 EV	274	if (!zone)
d7817ff2 EV	275	return -ENOMEM;
68acc77a PA	276
	277	zone->sensor_id = i;
	278	zone->scpi_sensors = scpi_sensors;
d7817ff2 EV	279	z = devm_thermal_zone_of_sensor_register(dev,
	280	sensor->info.sensor_id,
	281	zone,
	282	&scpi_sensor_ops);
68acc77a PA	283	/*
	284	* The call to thermal_zone_of_sensor_register returns
	285	* an error for sensors that are not associated with
	286	* any thermal zones or if the thermal subsystem is
	287	* not configured.
	288	*/
d7817ff2	289	if (IS_ERR(z)) {
68acc77a PA	290	devm_kfree(dev, zone);
	291	continue;
	292	}
68acc77a PA	293	}
68acc77a PA	294
68acc77a	295	return 0;
ea98b29a PA	296	}
ea98b29a PA	297
ea98b29a PA	298	static struct platform_driver scpi_hwmon_platdrv = {
	299	.driver = {
	300	.name = "scpi-hwmon",
ea98b29a PA	301	.of_match_table = scpi_of_match,
	302	},
	303	.probe = scpi_hwmon_probe,
	304	};
	305	module_platform_driver(scpi_hwmon_platdrv);
	306
	307	MODULE_AUTHOR("Punit Agrawal <punit.agrawal@arm.com>");
	308	MODULE_DESCRIPTION("ARM SCPI HWMON interface driver");
	309	MODULE_LICENSE("GPL v2");