linux/drivers/hwmon/scmi-hwmon.c
Nathan Chancellor a31796c30e hwmon: (scmi) Remove redundant pointer check
Clang warns when the address of a pointer is used in a boolean context
as it will always return true.

drivers/hwmon/scmi-hwmon.c:59:24: warning: address of array
'sensor->name' will always evaluate to 'true'
[-Wpointer-bool-conversion]
        if (sensor && sensor->name)
                   ~~ ~~~~~~~~^~~~
1 warning generated.

Remove the check as it isn't doing anything currently; if validation
of the contents of the data structure was intended by the original
author (since this line has been present from the first version of
this driver), it can be added in a follow-up patch.

Reported-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2018-10-10 20:37:13 -07:00

229 lines
5.4 KiB
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 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)
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_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");