https://github.com/torvalds/linux
Tip revision: 3d77e6a8804abcc0504c904bd6e5cdf3a5cf8162 authored by Linus Torvalds on 31 May 2020, 23:49:15 UTC
Linux 5.7
Linux 5.7
Tip revision: 3d77e6a
sensors.c
// SPDX-License-Identifier: GPL-2.0
/*
* System Control and Management Interface (SCMI) Sensor Protocol
*
* Copyright (C) 2018 ARM Ltd.
*/
#include "common.h"
enum scmi_sensor_protocol_cmd {
SENSOR_DESCRIPTION_GET = 0x3,
SENSOR_TRIP_POINT_NOTIFY = 0x4,
SENSOR_TRIP_POINT_CONFIG = 0x5,
SENSOR_READING_GET = 0x6,
};
struct scmi_msg_resp_sensor_attributes {
__le16 num_sensors;
u8 max_requests;
u8 reserved;
__le32 reg_addr_low;
__le32 reg_addr_high;
__le32 reg_size;
};
struct scmi_msg_resp_sensor_description {
__le16 num_returned;
__le16 num_remaining;
struct {
__le32 id;
__le32 attributes_low;
#define SUPPORTS_ASYNC_READ(x) ((x) & BIT(31))
#define NUM_TRIP_POINTS(x) ((x) & 0xff)
__le32 attributes_high;
#define SENSOR_TYPE(x) ((x) & 0xff)
#define SENSOR_SCALE(x) (((x) >> 11) & 0x1f)
#define SENSOR_SCALE_SIGN BIT(4)
#define SENSOR_SCALE_EXTEND GENMASK(7, 5)
#define SENSOR_UPDATE_SCALE(x) (((x) >> 22) & 0x1f)
#define SENSOR_UPDATE_BASE(x) (((x) >> 27) & 0x1f)
u8 name[SCMI_MAX_STR_SIZE];
} desc[0];
};
struct scmi_msg_sensor_trip_point_notify {
__le32 id;
__le32 event_control;
#define SENSOR_TP_NOTIFY_ALL BIT(0)
};
struct scmi_msg_set_sensor_trip_point {
__le32 id;
__le32 event_control;
#define SENSOR_TP_EVENT_MASK (0x3)
#define SENSOR_TP_DISABLED 0x0
#define SENSOR_TP_POSITIVE 0x1
#define SENSOR_TP_NEGATIVE 0x2
#define SENSOR_TP_BOTH 0x3
#define SENSOR_TP_ID(x) (((x) & 0xff) << 4)
__le32 value_low;
__le32 value_high;
};
struct scmi_msg_sensor_reading_get {
__le32 id;
__le32 flags;
#define SENSOR_READ_ASYNC BIT(0)
};
struct sensors_info {
u32 version;
int num_sensors;
int max_requests;
u64 reg_addr;
u32 reg_size;
struct scmi_sensor_info *sensors;
};
static int scmi_sensor_attributes_get(const struct scmi_handle *handle,
struct sensors_info *si)
{
int ret;
struct scmi_xfer *t;
struct scmi_msg_resp_sensor_attributes *attr;
ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
SCMI_PROTOCOL_SENSOR, 0, sizeof(*attr), &t);
if (ret)
return ret;
attr = t->rx.buf;
ret = scmi_do_xfer(handle, t);
if (!ret) {
si->num_sensors = le16_to_cpu(attr->num_sensors);
si->max_requests = attr->max_requests;
si->reg_addr = le32_to_cpu(attr->reg_addr_low) |
(u64)le32_to_cpu(attr->reg_addr_high) << 32;
si->reg_size = le32_to_cpu(attr->reg_size);
}
scmi_xfer_put(handle, t);
return ret;
}
static int scmi_sensor_description_get(const struct scmi_handle *handle,
struct sensors_info *si)
{
int ret, cnt;
u32 desc_index = 0;
u16 num_returned, num_remaining;
struct scmi_xfer *t;
struct scmi_msg_resp_sensor_description *buf;
ret = scmi_xfer_get_init(handle, SENSOR_DESCRIPTION_GET,
SCMI_PROTOCOL_SENSOR, sizeof(__le32), 0, &t);
if (ret)
return ret;
buf = t->rx.buf;
do {
/* Set the number of sensors to be skipped/already read */
put_unaligned_le32(desc_index, t->tx.buf);
ret = scmi_do_xfer(handle, t);
if (ret)
break;
num_returned = le16_to_cpu(buf->num_returned);
num_remaining = le16_to_cpu(buf->num_remaining);
if (desc_index + num_returned > si->num_sensors) {
dev_err(handle->dev, "No. of sensors can't exceed %d",
si->num_sensors);
break;
}
for (cnt = 0; cnt < num_returned; cnt++) {
u32 attrh, attrl;
struct scmi_sensor_info *s;
attrl = le32_to_cpu(buf->desc[cnt].attributes_low);
attrh = le32_to_cpu(buf->desc[cnt].attributes_high);
s = &si->sensors[desc_index + cnt];
s->id = le32_to_cpu(buf->desc[cnt].id);
s->type = SENSOR_TYPE(attrh);
s->scale = SENSOR_SCALE(attrh);
/* Sign extend to a full s8 */
if (s->scale & SENSOR_SCALE_SIGN)
s->scale |= SENSOR_SCALE_EXTEND;
s->async = SUPPORTS_ASYNC_READ(attrl);
s->num_trip_points = NUM_TRIP_POINTS(attrl);
strlcpy(s->name, buf->desc[cnt].name, SCMI_MAX_STR_SIZE);
}
desc_index += num_returned;
/*
* check for both returned and remaining to avoid infinite
* loop due to buggy firmware
*/
} while (num_returned && num_remaining);
scmi_xfer_put(handle, t);
return ret;
}
static int scmi_sensor_trip_point_notify(const struct scmi_handle *handle,
u32 sensor_id, bool enable)
{
int ret;
u32 evt_cntl = enable ? SENSOR_TP_NOTIFY_ALL : 0;
struct scmi_xfer *t;
struct scmi_msg_sensor_trip_point_notify *cfg;
ret = scmi_xfer_get_init(handle, SENSOR_TRIP_POINT_NOTIFY,
SCMI_PROTOCOL_SENSOR, sizeof(*cfg), 0, &t);
if (ret)
return ret;
cfg = t->tx.buf;
cfg->id = cpu_to_le32(sensor_id);
cfg->event_control = cpu_to_le32(evt_cntl);
ret = scmi_do_xfer(handle, t);
scmi_xfer_put(handle, t);
return ret;
}
static int
scmi_sensor_trip_point_config(const struct scmi_handle *handle, u32 sensor_id,
u8 trip_id, u64 trip_value)
{
int ret;
u32 evt_cntl = SENSOR_TP_BOTH;
struct scmi_xfer *t;
struct scmi_msg_set_sensor_trip_point *trip;
ret = scmi_xfer_get_init(handle, SENSOR_TRIP_POINT_CONFIG,
SCMI_PROTOCOL_SENSOR, sizeof(*trip), 0, &t);
if (ret)
return ret;
trip = t->tx.buf;
trip->id = cpu_to_le32(sensor_id);
trip->event_control = cpu_to_le32(evt_cntl | SENSOR_TP_ID(trip_id));
trip->value_low = cpu_to_le32(trip_value & 0xffffffff);
trip->value_high = cpu_to_le32(trip_value >> 32);
ret = scmi_do_xfer(handle, t);
scmi_xfer_put(handle, t);
return ret;
}
static int scmi_sensor_reading_get(const struct scmi_handle *handle,
u32 sensor_id, u64 *value)
{
int ret;
struct scmi_xfer *t;
struct scmi_msg_sensor_reading_get *sensor;
struct sensors_info *si = handle->sensor_priv;
struct scmi_sensor_info *s = si->sensors + sensor_id;
ret = scmi_xfer_get_init(handle, SENSOR_READING_GET,
SCMI_PROTOCOL_SENSOR, sizeof(*sensor),
sizeof(u64), &t);
if (ret)
return ret;
sensor = t->tx.buf;
sensor->id = cpu_to_le32(sensor_id);
if (s->async) {
sensor->flags = cpu_to_le32(SENSOR_READ_ASYNC);
ret = scmi_do_xfer_with_response(handle, t);
if (!ret)
*value = get_unaligned_le64((void *)
((__le32 *)t->rx.buf + 1));
} else {
sensor->flags = cpu_to_le32(0);
ret = scmi_do_xfer(handle, t);
if (!ret)
*value = get_unaligned_le64(t->rx.buf);
}
scmi_xfer_put(handle, t);
return ret;
}
static const struct scmi_sensor_info *
scmi_sensor_info_get(const struct scmi_handle *handle, u32 sensor_id)
{
struct sensors_info *si = handle->sensor_priv;
return si->sensors + sensor_id;
}
static int scmi_sensor_count_get(const struct scmi_handle *handle)
{
struct sensors_info *si = handle->sensor_priv;
return si->num_sensors;
}
static struct scmi_sensor_ops sensor_ops = {
.count_get = scmi_sensor_count_get,
.info_get = scmi_sensor_info_get,
.trip_point_notify = scmi_sensor_trip_point_notify,
.trip_point_config = scmi_sensor_trip_point_config,
.reading_get = scmi_sensor_reading_get,
};
static int scmi_sensors_protocol_init(struct scmi_handle *handle)
{
u32 version;
struct sensors_info *sinfo;
scmi_version_get(handle, SCMI_PROTOCOL_SENSOR, &version);
dev_dbg(handle->dev, "Sensor Version %d.%d\n",
PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
sinfo = devm_kzalloc(handle->dev, sizeof(*sinfo), GFP_KERNEL);
if (!sinfo)
return -ENOMEM;
scmi_sensor_attributes_get(handle, sinfo);
sinfo->sensors = devm_kcalloc(handle->dev, sinfo->num_sensors,
sizeof(*sinfo->sensors), GFP_KERNEL);
if (!sinfo->sensors)
return -ENOMEM;
scmi_sensor_description_get(handle, sinfo);
sinfo->version = version;
handle->sensor_ops = &sensor_ops;
handle->sensor_priv = sinfo;
return 0;
}
static int __init scmi_sensors_init(void)
{
return scmi_protocol_register(SCMI_PROTOCOL_SENSOR,
&scmi_sensors_protocol_init);
}
subsys_initcall(scmi_sensors_init);