1/* 2 * drivers/hwmon/wm831x-hwmon.c - Wolfson Microelectronics WM831x PMIC 3 * hardware monitoring features. 4 * 5 * Copyright (C) 2009 Wolfson Microelectronics plc 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License v2 as published by the 9 * Free Software Foundation. 10 * 11 * This program is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 * 16 * You should have received a copy of the GNU General Public License along with 17 * this program; if not, write to the Free Software Foundation, Inc., 18 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA 19 */ 20 21#include <linux/kernel.h> 22#include <linux/module.h> 23#include <linux/platform_device.h> 24#include <linux/err.h> 25#include <linux/hwmon.h> 26#include <linux/hwmon-sysfs.h> 27#include <linux/slab.h> 28 29#include <linux/mfd/wm831x/core.h> 30#include <linux/mfd/wm831x/auxadc.h> 31 32struct wm831x_hwmon { 33 struct wm831x *wm831x; 34 struct device *classdev; 35}; 36 37static ssize_t show_name(struct device *dev, 38 struct device_attribute *attr, char *buf) 39{ 40 return sprintf(buf, "wm831x\n"); 41} 42 43static const char *input_names[] = { 44 [WM831X_AUX_SYSVDD] = "SYSVDD", 45 [WM831X_AUX_USB] = "USB", 46 [WM831X_AUX_BKUP_BATT] = "Backup battery", 47 [WM831X_AUX_BATT] = "Battery", 48 [WM831X_AUX_WALL] = "WALL", 49 [WM831X_AUX_CHIP_TEMP] = "PMIC", 50 [WM831X_AUX_BATT_TEMP] = "Battery", 51}; 52 53 54static ssize_t show_voltage(struct device *dev, 55 struct device_attribute *attr, char *buf) 56{ 57 struct wm831x_hwmon *hwmon = dev_get_drvdata(dev); 58 int channel = to_sensor_dev_attr(attr)->index; 59 int ret; 60 61 ret = wm831x_auxadc_read_uv(hwmon->wm831x, channel); 62 if (ret < 0) 63 return ret; 64 65 return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(ret, 1000)); 66} 67 68static ssize_t show_chip_temp(struct device *dev, 69 struct device_attribute *attr, char *buf) 70{ 71 struct wm831x_hwmon *hwmon = dev_get_drvdata(dev); 72 int channel = to_sensor_dev_attr(attr)->index; 73 int ret; 74 75 ret = wm831x_auxadc_read(hwmon->wm831x, channel); 76 if (ret < 0) 77 return ret; 78 79 /* Degrees celsius = (512.18-ret) / 1.0983 */ 80 ret = 512180 - (ret * 1000); 81 ret = DIV_ROUND_CLOSEST(ret * 10000, 10983); 82 83 return sprintf(buf, "%d\n", ret); 84} 85 86static ssize_t show_label(struct device *dev, 87 struct device_attribute *attr, char *buf) 88{ 89 int channel = to_sensor_dev_attr(attr)->index; 90 91 return sprintf(buf, "%s\n", input_names[channel]); 92} 93 94#define WM831X_VOLTAGE(id, name) \ 95 static SENSOR_DEVICE_ATTR(in##id##_input, S_IRUGO, show_voltage, \ 96 NULL, name) 97 98#define WM831X_NAMED_VOLTAGE(id, name) \ 99 WM831X_VOLTAGE(id, name); \ 100 static SENSOR_DEVICE_ATTR(in##id##_label, S_IRUGO, show_label, \ 101 NULL, name) 102 103static DEVICE_ATTR(name, S_IRUGO, show_name, NULL); 104 105WM831X_VOLTAGE(0, WM831X_AUX_AUX1); 106WM831X_VOLTAGE(1, WM831X_AUX_AUX2); 107WM831X_VOLTAGE(2, WM831X_AUX_AUX3); 108WM831X_VOLTAGE(3, WM831X_AUX_AUX4); 109 110WM831X_NAMED_VOLTAGE(4, WM831X_AUX_SYSVDD); 111WM831X_NAMED_VOLTAGE(5, WM831X_AUX_USB); 112WM831X_NAMED_VOLTAGE(6, WM831X_AUX_BATT); 113WM831X_NAMED_VOLTAGE(7, WM831X_AUX_WALL); 114WM831X_NAMED_VOLTAGE(8, WM831X_AUX_BKUP_BATT); 115 116static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, show_chip_temp, NULL, 117 WM831X_AUX_CHIP_TEMP); 118static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL, 119 WM831X_AUX_CHIP_TEMP); 120/* Report as a voltage since conversion depends on external components 121 * and that's what the ABI wants. */ 122static SENSOR_DEVICE_ATTR(temp2_input, S_IRUGO, show_voltage, NULL, 123 WM831X_AUX_BATT_TEMP); 124static SENSOR_DEVICE_ATTR(temp2_label, S_IRUGO, show_label, NULL, 125 WM831X_AUX_BATT_TEMP); 126 127static struct attribute *wm831x_attributes[] = { 128 &dev_attr_name.attr, 129 130 &sensor_dev_attr_in0_input.dev_attr.attr, 131 &sensor_dev_attr_in1_input.dev_attr.attr, 132 &sensor_dev_attr_in2_input.dev_attr.attr, 133 &sensor_dev_attr_in3_input.dev_attr.attr, 134 135 &sensor_dev_attr_in4_input.dev_attr.attr, 136 &sensor_dev_attr_in4_label.dev_attr.attr, 137 &sensor_dev_attr_in5_input.dev_attr.attr, 138 &sensor_dev_attr_in5_label.dev_attr.attr, 139 &sensor_dev_attr_in6_input.dev_attr.attr, 140 &sensor_dev_attr_in6_label.dev_attr.attr, 141 &sensor_dev_attr_in7_input.dev_attr.attr, 142 &sensor_dev_attr_in7_label.dev_attr.attr, 143 &sensor_dev_attr_in8_input.dev_attr.attr, 144 &sensor_dev_attr_in8_label.dev_attr.attr, 145 146 &sensor_dev_attr_temp1_input.dev_attr.attr, 147 &sensor_dev_attr_temp1_label.dev_attr.attr, 148 &sensor_dev_attr_temp2_input.dev_attr.attr, 149 &sensor_dev_attr_temp2_label.dev_attr.attr, 150 151 NULL 152}; 153 154static const struct attribute_group wm831x_attr_group = { 155 .attrs = wm831x_attributes, 156}; 157 158static int __devinit wm831x_hwmon_probe(struct platform_device *pdev) 159{ 160 struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent); 161 struct wm831x_hwmon *hwmon; 162 int ret; 163 164 hwmon = kzalloc(sizeof(struct wm831x_hwmon), GFP_KERNEL); 165 if (!hwmon) 166 return -ENOMEM; 167 168 hwmon->wm831x = wm831x; 169 170 ret = sysfs_create_group(&pdev->dev.kobj, &wm831x_attr_group); 171 if (ret) 172 goto err; 173 174 hwmon->classdev = hwmon_device_register(&pdev->dev); 175 if (IS_ERR(hwmon->classdev)) { 176 ret = PTR_ERR(hwmon->classdev); 177 goto err_sysfs; 178 } 179 180 platform_set_drvdata(pdev, hwmon); 181 182 return 0; 183 184err_sysfs: 185 sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group); 186err: 187 kfree(hwmon); 188 return ret; 189} 190 191static int __devexit wm831x_hwmon_remove(struct platform_device *pdev) 192{ 193 struct wm831x_hwmon *hwmon = platform_get_drvdata(pdev); 194 195 hwmon_device_unregister(hwmon->classdev); 196 sysfs_remove_group(&pdev->dev.kobj, &wm831x_attr_group); 197 platform_set_drvdata(pdev, NULL); 198 kfree(hwmon); 199 200 return 0; 201} 202 203static struct platform_driver wm831x_hwmon_driver = { 204 .probe = wm831x_hwmon_probe, 205 .remove = __devexit_p(wm831x_hwmon_remove), 206 .driver = { 207 .name = "wm831x-hwmon", 208 .owner = THIS_MODULE, 209 }, 210}; 211 212static int __init wm831x_hwmon_init(void) 213{ 214 return platform_driver_register(&wm831x_hwmon_driver); 215} 216module_init(wm831x_hwmon_init); 217 218static void __exit wm831x_hwmon_exit(void) 219{ 220 platform_driver_unregister(&wm831x_hwmon_driver); 221} 222module_exit(wm831x_hwmon_exit); 223 224MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>"); 225MODULE_DESCRIPTION("WM831x Hardware Monitoring"); 226MODULE_LICENSE("GPL"); 227MODULE_ALIAS("platform:wm831x-hwmon"); 228