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path: root/drivers/hwmon/wm831x-hwmon.c
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Diffstat (limited to 'drivers/hwmon/wm831x-hwmon.c')
-rw-r--r--drivers/hwmon/wm831x-hwmon.c226
1 files changed, 226 insertions, 0 deletions
diff --git a/drivers/hwmon/wm831x-hwmon.c b/drivers/hwmon/wm831x-hwmon.c
new file mode 100644
index 00000000000..c16e9e74c35
--- /dev/null
+++ b/drivers/hwmon/wm831x-hwmon.c
@@ -0,0 +1,226 @@
+/*
+ * drivers/hwmon/wm831x-hwmon.c - Wolfson Microelectronics WM831x PMIC
+ * hardware monitoring features.
+ *
+ * Copyright (C) 2009 Wolfson Microelectronics plc
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License v2 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.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/err.h>
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+
+#include <linux/mfd/wm831x/core.h>
+#include <linux/mfd/wm831x/auxadc.h>
+
+struct wm831x_hwmon {
+ struct wm831x *wm831x;
+ struct device *classdev;
+};
+
+static ssize_t show_name(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ return sprintf(buf, "wm831x\n");
+}
+
+static const char *input_names[] = {
+ [WM831X_AUX_SYSVDD] = "SYSVDD",
+ [WM831X_AUX_USB] = "USB",
+ [WM831X_AUX_BKUP_BATT] = "Backup battery",
+ [WM831X_AUX_BATT] = "Battery",
+ [WM831X_AUX_WALL] = "WALL",
+ [WM831X_AUX_CHIP_TEMP] = "PMIC",
+ [WM831X_AUX_BATT_TEMP] = "Battery",
+};
+
+
+static ssize_t show_voltage(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wm831x_hwmon *hwmon = dev_get_drvdata(dev);
+ int channel = to_sensor_dev_attr(attr)->index;
+ int ret;
+
+ ret = wm831x_auxadc_read_uv(hwmon->wm831x, channel);
+ if (ret < 0)
+ return ret;
+
+ return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret, 1000));
+}
+
+static ssize_t show_chip_temp(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct wm831x_hwmon *hwmon = dev_get_drvdata(dev);
+ int channel = to_sensor_dev_attr(attr)->index;
+ int ret;
+
+ ret = wm831x_auxadc_read(hwmon->wm831x, channel);
+ if (ret < 0)
+ return ret;
+
+ /* Degrees celsius = (512.18-ret) / 1.0983 */
+ ret = 512180 - (ret * 1000);
+ ret = DIV_ROUND_CLOSEST(ret * 10000, 10983);
+
+ return sprintf(buf, "%d\n", ret);
+}
+
+static ssize_t show_label(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ int channel = to_sensor_dev_attr(attr)->index;
+
+ return sprintf(buf, "%s\n", input_names[channel]);
+}
+
+#define WM831X_VOLTAGE(id, name) \
+ static SENSOR_DEVICE_ATTR(in##id##_input, S_IRUGO, show_voltage, \
+ NULL, name)
+
+#define WM831X_NAMED_VOLTAGE(id, name) \
+ WM831X_VOLTAGE(id, name); \
+ static SENSOR_DEVICE_ATTR(in##id##_label, S_IRUGO, show_label, \
+ NULL, name)
+
+static DEVICE_ATTR(name, S_IRUGO, show_name, NULL);
+
+WM831X_VOLTAGE(0, WM831X_AUX_AUX1);
+WM831X_VOLTAGE(1, WM831X_AUX_AUX2);
+WM831X_VOLTAGE(2, WM831X_AUX_AUX3);
+WM831X_VOLTAGE(3, WM831X_AUX_AUX4);
+
+WM831X_NAMED_VOLTAGE(4, WM831X_AUX_SYSVDD);
+WM831X_NAMED_VOLTAGE(5, WM831X_AUX_USB);
+WM831X_NAMED_VOLTAGE(6, WM831X_AUX_BATT);
+WM831X_NAMED_VOLTAGE(7, WM831X_AUX_WALL);
+WM831X_NAMED_VOLTAGE(8, WM831X_AUX_BKUP_BATT);
+
+static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_chip_temp, NULL,
+ WM831X_AUX_CHIP_TEMP);
+static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
+ WM831X_AUX_CHIP_TEMP);
+/* Report as a voltage since conversion depends on external components
+ * and that's what the ABI wants. */
+static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_voltage, NULL,
+ WM831X_AUX_BATT_TEMP);
+static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL,
+ WM831X_AUX_BATT_TEMP);
+
+static struct attribute *wm831x_attributes[] = {
+ &dev_attr_name.attr,
+
+ &sensor_dev_attr_in0_input.dev_attr.attr,
+ &sensor_dev_attr_in1_input.dev_attr.attr,
+ &sensor_dev_attr_in2_input.dev_attr.attr,
+ &sensor_dev_attr_in3_input.dev_attr.attr,
+
+ &sensor_dev_attr_in4_input.dev_attr.attr,
+ &sensor_dev_attr_in4_label.dev_attr.attr,
+ &sensor_dev_attr_in5_input.dev_attr.attr,
+ &sensor_dev_attr_in5_label.dev_attr.attr,
+ &sensor_dev_attr_in6_input.dev_attr.attr,
+ &sensor_dev_attr_in6_label.dev_attr.attr,
+ &sensor_dev_attr_in7_input.dev_attr.attr,
+ &sensor_dev_attr_in7_label.dev_attr.attr,
+ &sensor_dev_attr_in8_input.dev_attr.attr,
+ &sensor_dev_attr_in8_label.dev_attr.attr,
+
+ &sensor_dev_attr_temp1_input.dev_attr.attr,
+ &sensor_dev_attr_temp1_label.dev_attr.attr,
+ &sensor_dev_attr_temp2_input.dev_attr.attr,
+ &sensor_dev_attr_temp2_label.dev_attr.attr,
+
+ NULL
+};
+
+static const struct attribute_group wm831x_attr_group = {
+ .attrs = wm831x_attributes,
+};
+
+static int __devinit wm831x_hwmon_probe(struct platform_device *pdev)
+{
+ struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
+ struct wm831x_hwmon *hwmon;
+ int ret;
+
+ hwmon = kzalloc(sizeof(struct wm831x_hwmon), GFP_KERNEL);
+ if (!hwmon)
+ return -ENOMEM;
+
+ hwmon->wm831x = wm831x;
+
+ ret = sysfs_create_group(&pdev->dev.kobj, &wm831x_attr_group);
+ if (ret)
+ goto err;
+
+ hwmon->classdev = hwmon_device_register(&pdev->dev);
+ if (IS_ERR(hwmon->classdev)) {
+ ret = PTR_ERR(hwmon->classdev);
+ goto err_sysfs;
+ }
+
+ platform_set_drvdata(pdev, hwmon);
+
+ return 0;
+
+err_sysfs:
+ sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group);
+err:
+ kfree(hwmon);
+ return ret;
+}
+
+static int __devexit wm831x_hwmon_remove(struct platform_device *pdev)
+{
+ struct wm831x_hwmon *hwmon = platform_get_drvdata(pdev);
+
+ hwmon_device_unregister(hwmon->classdev);
+ sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group);
+ platform_set_drvdata(pdev, NULL);
+ kfree(hwmon);
+
+ return 0;
+}
+
+static struct platform_driver wm831x_hwmon_driver = {
+ .probe = wm831x_hwmon_probe,
+ .remove = __devexit_p(wm831x_hwmon_remove),
+ .driver = {
+ .name = "wm831x-hwmon",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int __init wm831x_hwmon_init(void)
+{
+ return platform_driver_register(&wm831x_hwmon_driver);
+}
+module_init(wm831x_hwmon_init);
+
+static void __exit wm831x_hwmon_exit(void)
+{
+ platform_driver_unregister(&wm831x_hwmon_driver);
+}
+module_exit(wm831x_hwmon_exit);
+
+MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");
+MODULE_DESCRIPTION("WM831x Hardware Monitoring");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:wm831x-hwmon");