drivers/hwmon/vexpress.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify
   3  * it under the terms of the GNU General Public License version 2 as
   4  * published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   9  * GNU General Public License for more details.
  10  *
  11  * Copyright (C) 2012 ARM Limited
  12  */
  13
  14 #define DRVNAME "vexpress-hwmon"
  15 #define pr_fmt(fmt) DRVNAME ": " fmt
  16
  17 #include <linux/device.h>
  18 #include <linux/err.h>
  19 #include <linux/hwmon.h>
  20 #include <linux/hwmon-sysfs.h>
  21 #include <linux/module.h>
  22 #include <linux/of.h>
  23 #include <linux/of_device.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/vexpress.h>
  26
  27 struct vexpress_hwmon_data {
  28         struct device *hwmon_dev;
  29         struct vexpress_config_func *func;
  30         const char *name;
  31 };
  32
  33 static ssize_t vexpress_hwmon_name_show(struct device *dev,
  34                 struct device_attribute *dev_attr, char *buffer)
  35 {
  36         struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
  37
  38         return sprintf(buffer, "%s\n", data->name);
  39 }
  40
  41 static ssize_t vexpress_hwmon_label_show(struct device *dev,
  42                 struct device_attribute *dev_attr, char *buffer)
  43 {
  44         const char *label = of_get_property(dev->of_node, "label", NULL);
  45
  46         return snprintf(buffer, PAGE_SIZE, "%s\n", label);
  47 }
  48
  49 static ssize_t vexpress_hwmon_u32_show(struct device *dev,
  50                 struct device_attribute *dev_attr, char *buffer)
  51 {
  52         struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
  53         int err;
  54         u32 value;
  55
  56         err = vexpress_config_read(data->func, 0, &value);
  57         if (err)
  58                 return err;
  59
  60         return snprintf(buffer, PAGE_SIZE, "%u\n", value /
  61                         to_sensor_dev_attr(dev_attr)->index);
  62 }
  63
  64 static ssize_t vexpress_hwmon_u64_show(struct device *dev,
  65                 struct device_attribute *dev_attr, char *buffer)
  66 {
  67         struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
  68         int err;
  69         u32 value_hi, value_lo;
  70
  71         err = vexpress_config_read(data->func, 0, &value_lo);
  72         if (err)
  73                 return err;
  74
  75         err = vexpress_config_read(data->func, 1, &value_hi);
  76         if (err)
  77                 return err;
  78
  79         return snprintf(buffer, PAGE_SIZE, "%llu\n",
  80                         div_u64(((u64)value_hi << 32) | value_lo,
  81                         to_sensor_dev_attr(dev_attr)->index));
  82 }
  83
  84 static umode_t vexpress_hwmon_attr_is_visible(struct kobject *kobj,
  85                 struct attribute *attr, int index)
  86 {
  87         struct device *dev = kobj_to_dev(kobj);
  88         struct device_attribute *dev_attr = container_of(attr,
  89                                 struct device_attribute, attr);
  90
  91         if (dev_attr->show == vexpress_hwmon_label_show &&
  92                         !of_get_property(dev->of_node, "label", NULL))
  93                 return 0;
  94
  95         return attr->mode;
  96 }
  97
  98 static DEVICE_ATTR(name, S_IRUGO, vexpress_hwmon_name_show, NULL);
  99
 100 #define VEXPRESS_HWMON_ATTRS(_name, _label_attr, _input_attr)   \
 101 struct attribute *vexpress_hwmon_attrs_##_name[] = {            \
 102         &dev_attr_name.attr,                                    \
 103         &dev_attr_##_label_attr.attr,                           \
 104         &sensor_dev_attr_##_input_attr.dev_attr.attr,           \
 105         NULL                                                    \
 106 }
 107
 108 struct vexpress_hwmon_type {
 109         const char *name;
 110         const struct attribute_group **attr_groups;
 111 };
 112
 113 #if !defined(CONFIG_REGULATOR_VEXPRESS)
 114 static DEVICE_ATTR(in1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 115 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, vexpress_hwmon_u32_show,
 116                 NULL, 1000);
 117 static VEXPRESS_HWMON_ATTRS(volt, in1_label, in1_input);
 118 static struct attribute_group vexpress_hwmon_group_volt = {
 119         .is_visible = vexpress_hwmon_attr_is_visible,
 120         .attrs = vexpress_hwmon_attrs_volt,
 121 };
 122 static struct vexpress_hwmon_type vexpress_hwmon_volt = {
 123         .name = "vexpress_volt",
 124         .attr_groups = (const struct attribute_group *[]) {
 125                 &vexpress_hwmon_group_volt,
 126                 NULL,
 127         },
 128 };
 129 #endif
 130
 131 static DEVICE_ATTR(curr1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 132 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, vexpress_hwmon_u32_show,
 133                 NULL, 1000);
 134 static VEXPRESS_HWMON_ATTRS(amp, curr1_label, curr1_input);
 135 static struct attribute_group vexpress_hwmon_group_amp = {
 136         .is_visible = vexpress_hwmon_attr_is_visible,
 137         .attrs = vexpress_hwmon_attrs_amp,
 138 };
 139 static struct vexpress_hwmon_type vexpress_hwmon_amp = {
 140         .name = "vexpress_amp",
 141         .attr_groups = (const struct attribute_group *[]) {
 142                 &vexpress_hwmon_group_amp,
 143                 NULL
 144         },
 145 };
 146
 147 static DEVICE_ATTR(temp1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 148 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, vexpress_hwmon_u32_show,
 149                 NULL, 1000);
 150 static VEXPRESS_HWMON_ATTRS(temp, temp1_label, temp1_input);
 151 static struct attribute_group vexpress_hwmon_group_temp = {
 152         .is_visible = vexpress_hwmon_attr_is_visible,
 153         .attrs = vexpress_hwmon_attrs_temp,
 154 };
 155 static struct vexpress_hwmon_type vexpress_hwmon_temp = {
 156         .name = "vexpress_temp",
 157         .attr_groups = (const struct attribute_group *[]) {
 158                 &vexpress_hwmon_group_temp,
 159                 NULL
 160         },
 161 };
 162
 163 static DEVICE_ATTR(power1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 164 static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, vexpress_hwmon_u32_show,
 165                 NULL, 1);
 166 static VEXPRESS_HWMON_ATTRS(power, power1_label, power1_input);
 167 static struct attribute_group vexpress_hwmon_group_power = {
 168         .is_visible = vexpress_hwmon_attr_is_visible,
 169         .attrs = vexpress_hwmon_attrs_power,
 170 };
 171 static struct vexpress_hwmon_type vexpress_hwmon_power = {
 172         .name = "vexpress_power",
 173         .attr_groups = (const struct attribute_group *[]) {
 174                 &vexpress_hwmon_group_power,
 175                 NULL
 176         },
 177 };
 178
 179 static DEVICE_ATTR(energy1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 180 static SENSOR_DEVICE_ATTR(energy1_input, S_IRUGO, vexpress_hwmon_u64_show,
 181                 NULL, 1);
 182 static VEXPRESS_HWMON_ATTRS(energy, energy1_label, energy1_input);
 183 static struct attribute_group vexpress_hwmon_group_energy = {
 184         .is_visible = vexpress_hwmon_attr_is_visible,
 185         .attrs = vexpress_hwmon_attrs_energy,
 186 };
 187 static struct vexpress_hwmon_type vexpress_hwmon_energy = {
 188         .name = "vexpress_energy",
 189         .attr_groups = (const struct attribute_group *[]) {
 190                 &vexpress_hwmon_group_energy,
 191                 NULL
 192         },
 193 };
 194
 195 static struct of_device_id vexpress_hwmon_of_match[] = {
 196 #if !defined(CONFIG_REGULATOR_VEXPRESS)
 197         {
 198                 .compatible = "arm,vexpress-volt",
 199                 .data = &vexpress_hwmon_volt,
 200         },
 201 #endif
 202         {
 203                 .compatible = "arm,vexpress-amp",
 204                 .data = &vexpress_hwmon_amp,
 205         }, {
 206                 .compatible = "arm,vexpress-temp",
 207                 .data = &vexpress_hwmon_temp,
 208         }, {
 209                 .compatible = "arm,vexpress-power",
 210                 .data = &vexpress_hwmon_power,
 211         }, {
 212                 .compatible = "arm,vexpress-energy",
 213                 .data = &vexpress_hwmon_energy,
 214         },
 215         {}
 216 };
 217 MODULE_DEVICE_TABLE(of, vexpress_hwmon_of_match);
 218
 219 static int vexpress_hwmon_probe(struct platform_device *pdev)
 220 {
 221         int err;
 222         const struct of_device_id *match;
 223         struct vexpress_hwmon_data *data;
 224         const struct vexpress_hwmon_type *type;
 225
 226         data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
 227         if (!data)
 228                 return -ENOMEM;
 229         platform_set_drvdata(pdev, data);
 230
 231         match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
 232         if (!match)
 233                 return -ENODEV;
 234         type = match->data;
 235         data->name = type->name;
 236
 237         data->func = vexpress_config_func_get_by_dev(&pdev->dev);
 238         if (!data->func)
 239                 return -ENODEV;
 240
 241         err = sysfs_create_groups(&pdev->dev.kobj, type->attr_groups);
 242         if (err)
 243                 goto error;
 244
 245         data->hwmon_dev = hwmon_device_register(&pdev->dev);
 246         if (IS_ERR(data->hwmon_dev)) {
 247                 err = PTR_ERR(data->hwmon_dev);
 248                 goto error;
 249         }
 250
 251         return 0;
 252
 253 error:
 254         sysfs_remove_group(&pdev->dev.kobj, match->data);
 255         vexpress_config_func_put(data->func);
 256         return err;
 257 }
 258
 259 static int vexpress_hwmon_remove(struct platform_device *pdev)
 260 {
 261         struct vexpress_hwmon_data *data = platform_get_drvdata(pdev);
 262         const struct of_device_id *match;
 263
 264         hwmon_device_unregister(data->hwmon_dev);
 265
 266         match = of_match_device(vexpress_hwmon_of_match, &pdev->dev);
 267         sysfs_remove_group(&pdev->dev.kobj, match->data);
 268
 269         vexpress_config_func_put(data->func);
 270
 271         return 0;
 272 }
 273
 274 static struct platform_driver vexpress_hwmon_driver = {
 275         .probe = vexpress_hwmon_probe,
 276         .remove = vexpress_hwmon_remove,
 277         .driver = {
 278                 .name = DRVNAME,
 279                 .owner = THIS_MODULE,
 280                 .of_match_table = vexpress_hwmon_of_match,
 281         },
 282 };
 283
 284 module_platform_driver(vexpress_hwmon_driver);
 285
 286 MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
 287 MODULE_DESCRIPTION("Versatile Express hwmon sensors driver");
 288 MODULE_LICENSE("GPL");
 289 MODULE_ALIAS("platform:vexpress-hwmon");