drivers/hwmon/vexpress-hwmon.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 regmap *reg;
  30 };
  31
  32 static ssize_t vexpress_hwmon_label_show(struct device *dev,
  33                 struct device_attribute *dev_attr, char *buffer)
  34 {
  35         const char *label = of_get_property(dev->of_node, "label", NULL);
  36
  37         return snprintf(buffer, PAGE_SIZE, "%s\n", label);
  38 }
  39
  40 static ssize_t vexpress_hwmon_u32_show(struct device *dev,
  41                 struct device_attribute *dev_attr, char *buffer)
  42 {
  43         struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
  44         int err;
  45         u32 value;
  46
  47         err = regmap_read(data->reg, 0, &value);
  48         if (err)
  49                 return err;
  50
  51         return snprintf(buffer, PAGE_SIZE, "%u\n", value /
  52                         to_sensor_dev_attr(dev_attr)->index);
  53 }
  54
  55 static ssize_t vexpress_hwmon_u64_show(struct device *dev,
  56                 struct device_attribute *dev_attr, char *buffer)
  57 {
  58         struct vexpress_hwmon_data *data = dev_get_drvdata(dev);
  59         int err;
  60         u32 value_hi, value_lo;
  61
  62         err = regmap_read(data->reg, 0, &value_lo);
  63         if (err)
  64                 return err;
  65
  66         err = regmap_read(data->reg, 1, &value_hi);
  67         if (err)
  68                 return err;
  69
  70         return snprintf(buffer, PAGE_SIZE, "%llu\n",
  71                         div_u64(((u64)value_hi << 32) | value_lo,
  72                         to_sensor_dev_attr(dev_attr)->index));
  73 }
  74
  75 static umode_t vexpress_hwmon_attr_is_visible(struct kobject *kobj,
  76                 struct attribute *attr, int index)
  77 {
  78         struct device *dev = kobj_to_dev(kobj);
  79         struct device_attribute *dev_attr = container_of(attr,
  80                                 struct device_attribute, attr);
  81
  82         if (dev_attr->show == vexpress_hwmon_label_show &&
  83                         !of_get_property(dev->of_node, "label", NULL))
  84                 return 0;
  85
  86         return attr->mode;
  87 }
  88
  89 struct vexpress_hwmon_type {
  90         const char *name;
  91         const struct attribute_group **attr_groups;
  92 };
  93
  94 #if !defined(CONFIG_REGULATOR_VEXPRESS)
  95 static DEVICE_ATTR(in1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
  96 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, vexpress_hwmon_u32_show,
  97                 NULL, 1000);
  98 static struct attribute *vexpress_hwmon_attrs_volt[] = {
  99         &dev_attr_in1_label.attr,
 100         &sensor_dev_attr_in1_input.dev_attr.attr,
 101         NULL
 102 };
 103 static struct attribute_group vexpress_hwmon_group_volt = {
 104         .is_visible = vexpress_hwmon_attr_is_visible,
 105         .attrs = vexpress_hwmon_attrs_volt,
 106 };
 107 static struct vexpress_hwmon_type vexpress_hwmon_volt = {
 108         .name = "vexpress_volt",
 109         .attr_groups = (const struct attribute_group *[]) {
 110                 &vexpress_hwmon_group_volt,
 111                 NULL,
 112         },
 113 };
 114 #endif
 115
 116 static DEVICE_ATTR(curr1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 117 static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, vexpress_hwmon_u32_show,
 118                 NULL, 1000);
 119 static struct attribute *vexpress_hwmon_attrs_amp[] = {
 120         &dev_attr_curr1_label.attr,
 121         &sensor_dev_attr_curr1_input.dev_attr.attr,
 122         NULL
 123 };
 124 static struct attribute_group vexpress_hwmon_group_amp = {
 125         .is_visible = vexpress_hwmon_attr_is_visible,
 126         .attrs = vexpress_hwmon_attrs_amp,
 127 };
 128 static struct vexpress_hwmon_type vexpress_hwmon_amp = {
 129         .name = "vexpress_amp",
 130         .attr_groups = (const struct attribute_group *[]) {
 131                 &vexpress_hwmon_group_amp,
 132                 NULL
 133         },
 134 };
 135
 136 static DEVICE_ATTR(temp1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 137 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, vexpress_hwmon_u32_show,
 138                 NULL, 1000);
 139 static struct attribute *vexpress_hwmon_attrs_temp[] = {
 140         &dev_attr_temp1_label.attr,
 141         &sensor_dev_attr_temp1_input.dev_attr.attr,
 142         NULL
 143 };
 144 static struct attribute_group vexpress_hwmon_group_temp = {
 145         .is_visible = vexpress_hwmon_attr_is_visible,
 146         .attrs = vexpress_hwmon_attrs_temp,
 147 };
 148 static struct vexpress_hwmon_type vexpress_hwmon_temp = {
 149         .name = "vexpress_temp",
 150         .attr_groups = (const struct attribute_group *[]) {
 151                 &vexpress_hwmon_group_temp,
 152                 NULL
 153         },
 154 };
 155
 156 static DEVICE_ATTR(power1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 157 static SENSOR_DEVICE_ATTR(power1_input, S_IRUGO, vexpress_hwmon_u32_show,
 158                 NULL, 1);
 159 static struct attribute *vexpress_hwmon_attrs_power[] = {
 160         &dev_attr_power1_label.attr,
 161         &sensor_dev_attr_power1_input.dev_attr.attr,
 162         NULL
 163 };
 164 static struct attribute_group vexpress_hwmon_group_power = {
 165         .is_visible = vexpress_hwmon_attr_is_visible,
 166         .attrs = vexpress_hwmon_attrs_power,
 167 };
 168 static struct vexpress_hwmon_type vexpress_hwmon_power = {
 169         .name = "vexpress_power",
 170         .attr_groups = (const struct attribute_group *[]) {
 171                 &vexpress_hwmon_group_power,
 172                 NULL
 173         },
 174 };
 175
 176 static DEVICE_ATTR(energy1_label, S_IRUGO, vexpress_hwmon_label_show, NULL);
 177 static SENSOR_DEVICE_ATTR(energy1_input, S_IRUGO, vexpress_hwmon_u64_show,
 178                 NULL, 1);
 179 static struct attribute *vexpress_hwmon_attrs_energy[] = {
 180         &dev_attr_energy1_label.attr,
 181         &sensor_dev_attr_energy1_input.dev_attr.attr,
 182         NULL
 183 };
 184 static struct attribute_group vexpress_hwmon_group_energy = {
 185         .is_visible = vexpress_hwmon_attr_is_visible,
 186         .attrs = vexpress_hwmon_attrs_energy,
 187 };
 188 static struct vexpress_hwmon_type vexpress_hwmon_energy = {
 189         .name = "vexpress_energy",
 190         .attr_groups = (const struct attribute_group *[]) {
 191                 &vexpress_hwmon_group_energy,
 192                 NULL
 193         },
 194 };
 195
 196 static const struct of_device_id vexpress_hwmon_of_match[] = {
 197 #if !defined(CONFIG_REGULATOR_VEXPRESS)
 198         {
 199                 .compatible = "arm,vexpress-volt",
 200                 .data = &vexpress_hwmon_volt,
 201         },
 202 #endif
 203         {
 204                 .compatible = "arm,vexpress-amp",
 205                 .data = &vexpress_hwmon_amp,
 206         }, {
 207                 .compatible = "arm,vexpress-temp",
 208                 .data = &vexpress_hwmon_temp,
 209         }, {
 210                 .compatible = "arm,vexpress-power",
 211                 .data = &vexpress_hwmon_power,
 212         }, {
 213                 .compatible = "arm,vexpress-energy",
 214                 .data = &vexpress_hwmon_energy,
 215         },
 216         {}
 217 };
 218 MODULE_DEVICE_TABLE(of, vexpress_hwmon_of_match);
 219
 220 static int vexpress_hwmon_probe(struct platform_device *pdev)
 221 {
 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
 236         data->reg = devm_regmap_init_vexpress_config(&pdev->dev);
 237         if (IS_ERR(data->reg))
 238                 return PTR_ERR(data->reg);
 239
 240         data->hwmon_dev = devm_hwmon_device_register_with_groups(&pdev->dev,
 241                         type->name, data, type->attr_groups);
 242
 243         return PTR_ERR_OR_ZERO(data->hwmon_dev);
 244 }
 245
 246 static struct platform_driver vexpress_hwmon_driver = {
 247         .probe = vexpress_hwmon_probe,
 248         .driver = {
 249                 .name = DRVNAME,
 250                 .of_match_table = vexpress_hwmon_of_match,
 251         },
 252 };
 253
 254 module_platform_driver(vexpress_hwmon_driver);
 255
 256 MODULE_AUTHOR("Pawel Moll <pawel.moll@arm.com>");
 257 MODULE_DESCRIPTION("Versatile Express hwmon sensors driver");
 258 MODULE_LICENSE("GPL");
 259 MODULE_ALIAS("platform:vexpress-hwmon");