hwmon: (menf21bmc) Introduce MEN14F021P00 BMC HWMON driver

Added driver to support the 14F021P00 BMC Hardware Monitoring.
The BMC is a Board Management Controller including monitoring of the
board voltages.

Signed-off-by: Andreas Werner <andreas.werner@men.de>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
This commit is contained in:
Andreas Werner 2014-08-27 19:53:06 +02:00 committed by Lee Jones
parent 38433639af
commit 964356938f
4 changed files with 291 additions and 0 deletions

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@ -0,0 +1,50 @@
Kernel driver menf21bmc_hwmon
=============================
Supported chips:
* MEN 14F021P00
Prefix: 'menf21bmc_hwmon'
Adresses scanned: -
Author: Andreas Werner <andreas.werner@men.de>
Description
-----------
The menf21bmc is a Board Management Controller (BMC) which provides an I2C
interface to the host to access the features implemented in the BMC.
This driver gives access to the voltage monitoring feature of the main
voltages of the board.
The voltage sensors are connected to the ADC inputs of the BMC which is
a PIC16F917 Mikrocontroller.
Usage Notes
-----------
This driver is part of the MFD driver named "menf21bmc" and does
not auto-detect devices.
You will have to instantiate the MFD driver explicitly.
Please see Documentation/i2c/instantiating-devices for
details.
Sysfs entries
-------------
The following attributes are supported. All attributes are read only
The Limits are read once by the driver.
in0_input +3.3V input voltage
in1_input +5.0V input voltage
in2_input +12.0V input voltage
in3_input +5V Standby input voltage
in4_input VBAT (on board battery)
in[0-4]_min Minimum voltage limit
in[0-4]_max Maximum voltage limit
in0_label "MON_3_3V"
in1_label "MON_5V"
in2_label "MON_12V"
in3_label "5V_STANDBY"
in4_label "VBAT"

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@ -839,6 +839,16 @@ config SENSORS_MCP3021
This driver can also be built as a module. If so, the module
will be called mcp3021.
config SENSORS_MENF21BMC_HWMON
tristate "MEN 14F021P00 BMC Hardware Monitoring"
depends on MFD_MENF21BMC
help
Say Y here to include support for the MEN 14F021P00 BMC
hardware monitoring.
This driver can also be built as a module. If so the module
will be called menf21bmc_hwmon.
config SENSORS_ADCXX
tristate "National Semiconductor ADCxxxSxxx"
depends on SPI_MASTER

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@ -115,6 +115,7 @@ obj-$(CONFIG_SENSORS_MAX6650) += max6650.o
obj-$(CONFIG_SENSORS_MAX6697) += max6697.o
obj-$(CONFIG_SENSORS_MC13783_ADC)+= mc13783-adc.o
obj-$(CONFIG_SENSORS_MCP3021) += mcp3021.o
obj-$(CONFIG_SENSORS_MENF21BMC_HWMON) += menf21bmc_hwmon.o
obj-$(CONFIG_SENSORS_NCT6683) += nct6683.o
obj-$(CONFIG_SENSORS_NCT6775) += nct6775.o
obj-$(CONFIG_SENSORS_NTC_THERMISTOR) += ntc_thermistor.o

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@ -0,0 +1,230 @@
/*
* 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>
#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,
.owner = THIS_MODULE,
},
};
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");