diff options
Diffstat (limited to 'drivers/hwmon/wm831x-hwmon.c')
| -rw-r--r-- | drivers/hwmon/wm831x-hwmon.c | 226 |
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 000000000000..c16e9e74c356 --- /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"); |