[PATCH v3] hwmon: Versatile Express hwmon driver
Pawel Moll
pawel.moll at arm.com
Thu Sep 20 12:54:18 EDT 2012
hwmon framework driver for Versatile Express sensors, providing
information about board level voltage (only when regulator driver
is not configured), currents, temperature and power/energy usage.
Labels for the values can be defined as DT properties.
Signed-off-by: Pawel Moll <pawel.moll at arm.com>
---
.../devicetree/bindings/hwmon/vexpress.txt | 23 ++
Documentation/hwmon/vexpress | 34 +++
drivers/hwmon/Kconfig | 8 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/vexpress.c | 255 ++++++++++++++++++++
5 files changed, 321 insertions(+)
create mode 100644 Documentation/devicetree/bindings/hwmon/vexpress.txt
create mode 100644 Documentation/hwmon/vexpress
create mode 100644 drivers/hwmon/vexpress.c
diff --git a/Documentation/devicetree/bindings/hwmon/vexpress.txt b/Documentation/devicetree/bindings/hwmon/vexpress.txt
new file mode 100644
index 0000000..9c27ed6
--- /dev/null
+++ b/Documentation/devicetree/bindings/hwmon/vexpress.txt
@@ -0,0 +1,23 @@
+Versatile Express hwmon sensors
+-------------------------------
+
+Requires node properties:
+- "compatible" value : one of
+ "arm,vexpress-volt"
+ "arm,vexpress-amp"
+ "arm,vexpress-temp"
+ "arm,vexpress-power"
+ "arm,vexpress-energy"
+- "arm,vexpress-sysreg,func" when controlled via vexpress-sysreg
+ (see Documentation/devicetree/bindings/arm/vexpress-sysreg.txt
+ for more details)
+
+Optional node properties:
+- label : string describing the monitored value
+
+Example:
+ energy at 0 {
+ compatible = "arm,vexpress-energy";
+ arm,vexpress-sysreg,func = <13 0>;
+ label = "A15 Jcore";
+ };
diff --git a/Documentation/hwmon/vexpress b/Documentation/hwmon/vexpress
new file mode 100644
index 0000000..557d6d5
--- /dev/null
+++ b/Documentation/hwmon/vexpress
@@ -0,0 +1,34 @@
+Kernel driver vexpress
+======================
+
+Supported systems:
+ * ARM Ltd. Versatile Express platform
+ Prefix: 'vexpress'
+ Datasheets:
+ * "Hardware Description" sections of the Technical Reference Manuals
+ for the Versatile Express boards:
+ http://infocenter.arm.com/help/topic/com.arm.doc.subset.boards.express/index.html
+ * Section "4.4.14. System Configuration registers" of the V2M-P1 TRM:
+ http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0447-/index.html
+
+Author: Pawel Moll
+
+Description
+-----------
+
+Versatile Express platform (http://www.arm.com/versatileexpress/) is a
+reference & prototyping system for ARM Ltd. processors. It can be set up
+from a wide range of boards, each of them containing (apart of the main
+chip/FPGA) a number of microcontrollers responsible for platform
+configuration and control. Theses microcontrollers can also monitor the
+board and its environment by a number of internal and external sensors,
+providing information about power lines voltages and currents, board
+temperature and power usage. Some of them also calculate consumed energy
+and provide a cumulative use counter.
+
+The configuration devices are _not_ memory mapped and must be accessed
+via a custom interface, abstracted by the "vexpress_config" API.
+
+As these devices are non-discoverable, they must be described in a Device
+Tree passed to the kernel. Details of the DT binding for them can be found
+in Documentation/devicetree/bindings/hwmon/vexpress.txt.
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index b0a2e4c..7359a07 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -1187,6 +1187,14 @@ config SENSORS_TWL4030_MADC
This driver can also be built as a module. If so it will be called
twl4030-madc-hwmon.
+config SENSORS_VEXPRESS
+ tristate "Versatile Express"
+ depends on VEXPRESS_CONFIG
+ help
+ This driver provides support for hardware sensors available on
+ the ARM Ltd's Versatile Express platform. It can provide wide
+ range of information like temperature, power, energy.
+
config SENSORS_VIA_CPUTEMP
tristate "VIA CPU temperature sensor"
depends on X86
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 7aa9811..e719a7d 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -120,6 +120,7 @@ obj-$(CONFIG_SENSORS_TMP102) += tmp102.o
obj-$(CONFIG_SENSORS_TMP401) += tmp401.o
obj-$(CONFIG_SENSORS_TMP421) += tmp421.o
obj-$(CONFIG_SENSORS_TWL4030_MADC)+= twl4030-madc-hwmon.o
+obj-$(CONFIG_SENSORS_VEXPRESS) += vexpress.o
obj-$(CONFIG_SENSORS_VIA_CPUTEMP)+= via-cputemp.o
obj-$(CONFIG_SENSORS_VIA686A) += via686a.o
obj-$(CONFIG_SENSORS_VT1211) += vt1211.o
diff --git a/drivers/hwmon/vexpress.c b/drivers/hwmon/vexpress.c
new file mode 100644
index 0000000..d9f091e
--- /dev/null
+++ b/drivers/hwmon/vexpress.c
@@ -0,0 +1,255 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2012 ARM Limited
+ */
+
+#define DRVNAME "vexpress-hwmon"
+#define pr_fmt(fmt) DRVNAME ": " fmt
+
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/vexpress.h>
+
+struct vexpress_hwmon_data {
+ struct device *hwmon_dev;
+ struct vexpress_config_func *func;
+};
+
+struct vexpress_hwmon_attr {
+ struct device_attribute dev_attr;
+ u32 divisor;
+};
+
+static ssize_t vexpress_hwmon_name_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buffer)
+{
+ const char *compatible = of_get_property(dev->of_node, "compatible",
+ NULL);
+
+ return sprintf(buffer, "%s\n", compatible);
+}
+
+static ssize_t vexpress_hwmon_label_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buffer)
+{
+ const char *label = of_get_property(dev->of_node, "label", NULL);
+
+ return snprintf(buffer, PAGE_SIZE, "%s\n", label);
+}
+
+static ssize_t vexpress_hwmon_u32_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buffer)
+{
+ struct vexpress_hwmon_attr *attr = container_of(dev_attr,
+ struct vexpress_hwmon_attr, dev_attr);
+ struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
+ int err;
+ u32 value;
+
+ err = vexpress_config_read(data->func, 0, &value);
+ if (err)
+ return err;
+
+ return snprintf(buffer, PAGE_SIZE, "%u\n", value / attr->divisor);
+}
+
+static ssize_t vexpress_hwmon_u64_show(struct device *dev,
+ struct device_attribute *dev_attr, char *buffer)
+{
+ struct vexpress_hwmon_attr *attr = container_of(dev_attr,
+ struct vexpress_hwmon_attr, dev_attr);
+ struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
+ int err;
+ u32 value_hi, value_lo;
+
+ err = vexpress_config_read(data->func, 0, &value_lo);
+ if (err)
+ return err;
+
+ err = vexpress_config_read(data->func, 1, &value_hi);
+ if (err)
+ return err;
+
+ return snprintf(buffer, PAGE_SIZE, "%llu\n",
+ div_u64(((u64)value_hi << 32) | value_lo,
+ attr->divisor));
+}
+
+static DEVICE_ATTR(name, S_IRUGO, vexpress_hwmon_name_show, NULL);
+
+#define VEXPRESS_HWMON_ATTR(_name, _show, _divisor) \
+struct vexpress_hwmon_attr vexpress_hwmon_attr_##_name = { \
+ .dev_attr = __ATTR(_name, S_IRUGO, _show, NULL), \
+ .divisor = _divisor, \
+}
+
+#define VEXPRESS_HWMON_ATTRS(_name, _label_attr, _input_attr) \
+struct attribute *vexpress_hwmon_attrs_##_name[] = { \
+ &dev_attr_name.attr, \
+ &dev_attr_##_label_attr.attr, \
+ &vexpress_hwmon_attr_##_input_attr.dev_attr.attr, \
+ NULL \
+}
+
+#if !defined(CONFIG_REGULATOR_VEXPRESS)
+static DEVICE_ATTR(in1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
+static VEXPRESS_HWMON_ATTR(in1_input, vexpress_hwmon_u32_show, 1000);
+static VEXPRESS_HWMON_ATTRS(volt, in1_label, in1_input);
+static struct attribute_group vexpress_hwmon_group_volt = {
+ .attrs = vexpress_hwmon_attrs_volt,
+};
+#endif
+
+static DEVICE_ATTR(curr1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
+static VEXPRESS_HWMON_ATTR(curr1_input, vexpress_hwmon_u32_show, 1000);
+static VEXPRESS_HWMON_ATTRS(amp, curr1_label, curr1_input);
+static struct attribute_group vexpress_hwmon_group_amp = {
+ .attrs = vexpress_hwmon_attrs_amp,
+};
+
+static DEVICE_ATTR(temp1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
+static VEXPRESS_HWMON_ATTR(temp1_input, vexpress_hwmon_u32_show, 1000);
+static VEXPRESS_HWMON_ATTRS(temp, temp1_label, temp1_input);
+static struct attribute_group vexpress_hwmon_group_temp = {
+ .attrs = vexpress_hwmon_attrs_temp,
+};
+
+static DEVICE_ATTR(power1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
+static VEXPRESS_HWMON_ATTR(power1_input, vexpress_hwmon_u32_show, 1);
+static VEXPRESS_HWMON_ATTRS(power, power1_label, power1_input);
+static struct attribute_group vexpress_hwmon_group_power = {
+ .attrs = vexpress_hwmon_attrs_power,
+};
+
+static DEVICE_ATTR(energy1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
+static VEXPRESS_HWMON_ATTR(energy1_input, vexpress_hwmon_u64_show, 1);
+static VEXPRESS_HWMON_ATTRS(energy, energy1_label, energy1_input);
+static struct attribute_group vexpress_hwmon_group_energy = {
+ .attrs = vexpress_hwmon_attrs_energy,
+};
+
+static struct of_device_id vexpress_hwmon_of_match[] = {
+#if !defined(CONFIG_REGULATOR_VEXPRESS)
+ {
+ .compatible = "arm,vexpress-volt",
+ .data = &vexpress_hwmon_group_volt,
+ },
+#endif
+ {
+ .compatible = "arm,vexpress-amp",
+ .data = &vexpress_hwmon_group_amp,
+ }, {
+ .compatible = "arm,vexpress-temp",
+ .data = &vexpress_hwmon_group_temp,
+ }, {
+ .compatible = "arm,vexpress-power",
+ .data = &vexpress_hwmon_group_power,
+ }, {
+ .compatible = "arm,vexpress-energy",
+ .data = &vexpress_hwmon_group_energy,
+ },
+ {}
+};
+MODULE_DEVICE_TABLE(of, vexpress_hwmon_of_match);
+
+static int vexpress_hwmon_probe(struct platform_device *pdev)
+{
+ int err;
+ const struct of_device_id *match;
+ struct vexpress_hwmon_data *data;
+
+ data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+ if (!data) {
+ err = -ENOMEM;
+ goto error_kzalloc;
+ }
+
+ match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
+ if (!match) {
+ err = -EINVAL;
+ goto error_match_device;
+ }
+
+ data->func = vexpress_config_func_get_by_dev(&pdev->dev);
+ if (!data->func) {
+ err = -ENXIO;
+ goto error_get_func;
+ }
+
+ err = sysfs_create_group(&pdev->dev.kobj, match->data);
+ if (err)
+ goto error_create_group;
+
+ data->hwmon_dev = hwmon_device_register(&pdev->dev);
+ if (IS_ERR(data->hwmon_dev)) {
+ err = PTR_ERR(data->hwmon_dev);
+ goto error_hwmon_device_register;
+ }
+
+ platform_set_drvdata(pdev, data);
+
+ return 0;
+
+error_hwmon_device_register:
+ sysfs_remove_group(&pdev->dev.kobj, match->data);
+error_create_group:
+ vexpress_config_func_put(data->func);
+error_get_func:
+error_match_device:
+error_kzalloc:
+ return err;
+}
+
+static int __devexit vexpress_hwmon_remove(struct platform_device *pdev)
+{
+ struct vexpress_hwmon_data *data = platform_get_drvdata(pdev);
+ const struct of_device_id *match;
+
+ hwmon_device_unregister(data->hwmon_dev);
+
+ match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
+ sysfs_remove_group(&pdev->dev.kobj, match->data);
+
+ vexpress_config_func_put(data->func);
+
+ return 0;
+}
+
+static struct platform_driver vexpress_hwmon_driver = {
+ .probe = vexpress_hwmon_probe,
+ .remove = __devexit_p(vexpress_hwmon_remove),
+ .driver = {
+ .name = DRVNAME,
+ .owner = THIS_MODULE,
+ .of_match_table = vexpress_hwmon_of_match,
+ },
+};
+
+static int __init vexpress_hwmon_init(void)
+{
+ return platform_driver_register(&vexpress_hwmon_driver);
+}
+
+static void __exit vexpress_hwmon_exit(void)
+{
+ platform_driver_unregister(&vexpress_hwmon_driver);
+}
+
+MODULE_AUTHOR("Pawel Moll <pawel.moll at arm.com>");
+MODULE_DESCRIPTION("Versatile Express hwmon sensors driver");
+MODULE_LICENSE("GPL");
+
+module_init(vexpress_hwmon_init);
+module_exit(vexpress_hwmon_exit);
--
1.7.9.5
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