[PATCH v5 4/4] drivers/hwmon/menf21bmc_hwmon: introduce MEN14F021P00 BMC HWMON driver

From: Andreas Werner
Date: Tue Aug 26 2014 - 12:55:12 EST


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@xxxxxx>
---
Documentation/hwmon/menf21bmc | 49 +++++++++
drivers/hwmon/Kconfig | 7 ++
drivers/hwmon/Makefile | 1 +
drivers/hwmon/menf21bmc_hwmon.c | 230 ++++++++++++++++++++++++++++++++++++++++
4 files changed, 287 insertions(+)
create mode 100644 Documentation/hwmon/menf21bmc
create mode 100644 drivers/hwmon/menf21bmc_hwmon.c

diff --git a/Documentation/hwmon/menf21bmc b/Documentation/hwmon/menf21bmc
new file mode 100644
index 0000000..22b6840
--- /dev/null
+++ b/Documentation/hwmon/menf21bmc
@@ -0,0 +1,49 @@
+Kernel driver menf21bmc_hwmon
+=============================
+
+Supported chips:
+ * MEN 14F021P00
+ Prefix: 'menf21bmc_hwmon'
+ Adresses scanned: -
+
+Author: Andreas Werner <andreas.werner@xxxxxx>
+
+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 does not auto-detect devices. You will have to instantiate the
+devices 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"
+
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index 37908ff..db3a6eb 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -828,6 +828,13 @@ 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.
+
config SENSORS_ADCXX
tristate "National Semiconductor ADCxxxSxxx"
depends on SPI_MASTER
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 1362382..56ab872 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -114,6 +114,7 @@ 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
diff --git a/drivers/hwmon/menf21bmc_hwmon.c b/drivers/hwmon/menf21bmc_hwmon.c
new file mode 100644
index 0000000..2eaec6a
--- /dev/null
+++ b/drivers/hwmon/menf21bmc_hwmon.c
@@ -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 {
+ char valid;
+ struct i2c_client *i2c_client;
+ unsigned long last_update;
+ u16 in_val[BMC_VOLT_COUNT];
+ u16 in_min[BMC_VOLT_COUNT];
+ u16 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;
+ uint16_t 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 = 1;
+ }
+abort:
+ return data_ret;
+}
+
+static int menf21bmc_hwmon_get_volt_limits(struct menf21bmc_hwmon *drv_data)
+{
+ int i;
+ uint16_t 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@xxxxxx>");
+MODULE_DESCRIPTION("MEN 14F021P00 BMC hwmon");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:menf21bmc_hwmon");
--
2.0.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/