/*
* MEN 14F021P00 Board Management Controller (BMC) hwmon driver.
*
* This is the core hwmon driver of the MEN 14F021P00 BMC.
* The BMC monitors the board voltages which can be access with this
* driver through sysfs.
*
* Copyright (C) 2014 MEN Mikro Elektronik Nuernberg GmbH
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/jiffies.h>
#include <linux/slab.h>
#include <linux/i2c.h>
#include <linux/err.h>
#define DRV_NAME "menf21bmc_hwmon"
#define BMC_VOLT_COUNT 5
#define MENF21BMC_V33 0
#define MENF21BMC_V5 1
#define MENF21BMC_V12 2
#define MENF21BMC_V5_SB 3
#define MENF21BMC_VBAT 4
#define IDX_TO_VOLT_MIN_CMD(idx) (0x40 + idx)
#define IDX_TO_VOLT_MAX_CMD(idx) (0x50 + idx)
#define IDX_TO_VOLT_INP_CMD(idx) (0x60 + idx)
struct menf21bmc_hwmon {
bool valid;
struct i2c_client *i2c_client;
unsigned long last_update;
int in_val[BMC_VOLT_COUNT];
int in_min[BMC_VOLT_COUNT];
int in_max[BMC_VOLT_COUNT];
};
static const char *const input_names[] = {
[MENF21BMC_V33] = "MON_3_3V",
[MENF21BMC_V5] = "MON_5V",
[MENF21BMC_V12] = "MON_12V",
[MENF21BMC_V5_SB] = "5V_STANDBY",
[MENF21BMC_VBAT] = "VBAT"
};
static struct menf21bmc_hwmon *menf21bmc_hwmon_update(struct device *dev)
{
int i;
int val;
struct menf21bmc_hwmon *drv_data = dev_get_drvdata(dev);
struct menf21bmc_hwmon *data_ret = drv_data;
if (time_after(jiffies, drv_data->last_update + HZ)
|| !drv_data->valid) {
for (i = 0; i < BMC_VOLT_COUNT; i++) {
val = i2c_smbus_read_word_data(drv_data->i2c_client,
IDX_TO_VOLT_INP_CMD(i));
if (val < 0) {
data_ret = ERR_PTR(val);
goto abort;
}
drv_data->in_val[i] = val;
}
drv_data->last_update = jiffies;
drv_data->valid = true;
}
abort:
return data_ret;
}
static int menf21bmc_hwmon_get_volt_limits(struct menf21bmc_hwmon *drv_data)
{
int i, val;
for (i = 0; i < BMC_VOLT_COUNT; i++) {
val = i2c_smbus_read_word_data(drv_data->i2c_client,
IDX_TO_VOLT_MIN_CMD(i));
if (val < 0)
return val;
drv_data->in_min[i] = val;
val = i2c_smbus_read_word_data(drv_data->i2c_client,
IDX_TO_VOLT_MAX_CMD(i));
if (val < 0)
return val;
drv_data->in_max[i] = val;
}
return 0;
}
static ssize_t
show_label(struct device *dev, struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
return sprintf(buf, "%s\n", input_names[attr->index]);
}
static ssize_t
show_in(struct device *dev, struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct menf21bmc_hwmon *drv_data = menf21bmc_hwmon_update(dev);
if (IS_ERR(drv_data))
return PTR_ERR(drv_data);
return sprintf(buf, "%d\n", drv_data->in_val[attr->index]);
}
static ssize_t
show_min(struct device *dev, struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct menf21bmc_hwmon *drv_data = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", drv_data->in_min[attr->index]);
}
static ssize_t
show_max(struct device *dev, struct device_attribute *devattr, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct menf21bmc_hwmon *drv_data = dev_get_drvdata(dev);
return sprintf(buf, "%d\n", drv_data->in_max[attr->index]);
}
#define create_voltage_sysfs(idx) \
static SENSOR_DEVICE_ATTR(in##idx##_input, S_IRUGO, \
show_in, NULL, idx); \
static SENSOR_DEVICE_ATTR(in##idx##_min, S_IRUGO, \
show_min, NULL, idx); \
static SENSOR_DEVICE_ATTR(in##idx##_max, S_IRUGO, \
show_max, NULL, idx); \
static SENSOR_DEVICE_ATTR(in##idx##_label, S_IRUGO, \
show_label, NULL, idx);
create_voltage_sysfs(0);
create_voltage_sysfs(1);
create_voltage_sysfs(2);
create_voltage_sysfs(3);
create_voltage_sysfs(4);
static struct attribute *menf21bmc_hwmon_attrs[] = {
&sensor_dev_attr_in0_input.dev_attr.attr,
&sensor_dev_attr_in0_min.dev_attr.attr,
&sensor_dev_attr_in0_max.dev_attr.attr,
&sensor_dev_attr_in0_label.dev_attr.attr,
&sensor_dev_attr_in1_input.dev_attr.attr,
&sensor_dev_attr_in1_min.dev_attr.attr,
&sensor_dev_attr_in1_max.dev_attr.attr,
&sensor_dev_attr_in1_label.dev_attr.attr,
&sensor_dev_attr_in2_input.dev_attr.attr,
&sensor_dev_attr_in2_min.dev_attr.attr,
&sensor_dev_attr_in2_max.dev_attr.attr,
&sensor_dev_attr_in2_label.dev_attr.attr,
&sensor_dev_attr_in3_input.dev_attr.attr,
&sensor_dev_attr_in3_min.dev_attr.attr,
&sensor_dev_attr_in3_max.dev_attr.attr,
&sensor_dev_attr_in3_label.dev_attr.attr,
&sensor_dev_attr_in4_input.dev_attr.attr,
&sensor_dev_attr_in4_min.dev_attr.attr,
&sensor_dev_attr_in4_max.dev_attr.attr,
&sensor_dev_attr_in4_label.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(menf21bmc_hwmon);
static int menf21bmc_hwmon_probe(struct platform_device *pdev)
{
int ret;
struct menf21bmc_hwmon *drv_data;
struct i2c_client *i2c_client = to_i2c_client(pdev->dev.parent);
struct device *hwmon_dev;
drv_data = devm_kzalloc(&pdev->dev, sizeof(struct menf21bmc_hwmon),
GFP_KERNEL);
if (!drv_data)
return -ENOMEM;
drv_data->i2c_client = i2c_client;
ret = menf21bmc_hwmon_get_volt_limits(drv_data);
if (ret) {
dev_err(&pdev->dev, "failed to read sensor limits");
return ret;
}
hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev,
"menf21bmc", drv_data,
menf21bmc_hwmon_groups);
if (IS_ERR(hwmon_dev))
return PTR_ERR(hwmon_dev);
dev_info(&pdev->dev, "MEN 14F021P00 BMC hwmon device enabled");
return 0;
}
static struct platform_driver menf21bmc_hwmon = {
.probe = menf21bmc_hwmon_probe,
.driver = {
.name = DRV_NAME,
},
};
module_platform_driver(menf21bmc_hwmon);
MODULE_AUTHOR("Andreas Werner <andreas.werner@men.de>");
MODULE_DESCRIPTION("MEN 14F021P00 BMC hwmon");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:menf21bmc_hwmon");
