diff options
Diffstat (limited to 'drivers/hwmon/scmi-hwmon.c')
| -rw-r--r-- | drivers/hwmon/scmi-hwmon.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/drivers/hwmon/scmi-hwmon.c b/drivers/hwmon/scmi-hwmon.c new file mode 100644 index 000000000..91bfecdb3 --- /dev/null +++ b/drivers/hwmon/scmi-hwmon.c @@ -0,0 +1,228 @@ +// 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 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, false, &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 && sensor->name) + return S_IRUGO; + + 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_max] = { + [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"); |