drivers/hwmon/da9055-hwmon.c

   1 /*
   2  * HWMON Driver for Dialog DA9055
   3  *
   4  * Copyright(c) 2012 Dialog Semiconductor Ltd.
   5  *
   6  * Author: David Dajun Chen <dchen@diasemi.com>
   7  *
   8  *  This program is free software; you can redistribute  it and/or modify it
   9  *  under  the terms of  the GNU General  Public License as published by the
  10  *  Free Software Foundation;  either version 2 of the  License, or (at your
  11  *  option) any later version.
  12  *
  13  */
  14
  15 #include <linux/delay.h>
  16 #include <linux/err.h>
  17 #include <linux/hwmon.h>
  18 #include <linux/hwmon-sysfs.h>
  19 #include <linux/init.h>
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/platform_device.h>
  23 #include <linux/completion.h>
  24
  25 #include <linux/mfd/da9055/core.h>
  26 #include <linux/mfd/da9055/reg.h>
  27
  28 #define DA9055_ADCIN_DIV        102
  29 #define DA9055_VSYS_DIV 85
  30
  31 #define DA9055_ADC_VSYS 0
  32 #define DA9055_ADC_ADCIN1       1
  33 #define DA9055_ADC_ADCIN2       2
  34 #define DA9055_ADC_ADCIN3       3
  35 #define DA9055_ADC_TJUNC        4
  36
  37 struct da9055_hwmon {
  38         struct da9055   *da9055;
  39         struct device   *class_device;
  40         struct mutex    hwmon_lock;
  41         struct mutex    irq_lock;
  42         struct completion done;
  43 };
  44
  45 static const char * const input_names[] = {
  46         [DA9055_ADC_VSYS]       = "VSYS",
  47         [DA9055_ADC_ADCIN1]     = "ADC IN1",
  48         [DA9055_ADC_ADCIN2]     = "ADC IN2",
  49         [DA9055_ADC_ADCIN3]     = "ADC IN3",
  50         [DA9055_ADC_TJUNC]      = "CHIP TEMP",
  51 };
  52
  53 static const u8 chan_mux[DA9055_ADC_TJUNC + 1] = {
  54         [DA9055_ADC_VSYS]       = DA9055_ADC_MUX_VSYS,
  55         [DA9055_ADC_ADCIN1]     = DA9055_ADC_MUX_ADCIN1,
  56         [DA9055_ADC_ADCIN2]     = DA9055_ADC_MUX_ADCIN2,
  57         [DA9055_ADC_ADCIN3]     = DA9055_ADC_MUX_ADCIN3,
  58         [DA9055_ADC_TJUNC]      = DA9055_ADC_MUX_T_SENSE,
  59 };
  60
  61 static int da9055_adc_manual_read(struct da9055_hwmon *hwmon,
  62                                         unsigned char channel)
  63 {
  64         int ret;
  65         unsigned short calc_data;
  66         unsigned short data;
  67         unsigned char mux_sel;
  68         struct da9055 *da9055 = hwmon->da9055;
  69
  70         if (channel > DA9055_ADC_TJUNC)
  71                 return -EINVAL;
  72
  73         mutex_lock(&hwmon->irq_lock);
  74
  75         /* Selects desired MUX for manual conversion */
  76         mux_sel = chan_mux[channel] | DA9055_ADC_MAN_CONV;
  77
  78         ret = da9055_reg_write(da9055, DA9055_REG_ADC_MAN, mux_sel);
  79         if (ret < 0)
  80                 goto err;
  81
  82         /* Wait for an interrupt */
  83         if (!wait_for_completion_timeout(&hwmon->done,
  84                                         msecs_to_jiffies(500))) {
  85                 dev_err(da9055->dev,
  86                         "timeout waiting for ADC conversion interrupt\n");
  87                 ret = -ETIMEDOUT;
  88                 goto err;
  89         }
  90
  91         ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_H);
  92         if (ret < 0)
  93                 goto err;
  94
  95         calc_data = (unsigned short)ret;
  96         data = calc_data << 2;
  97
  98         ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_L);
  99         if (ret < 0)
 100                 goto err;
 101
 102         calc_data = (unsigned short)(ret & DA9055_ADC_LSB_MASK);
 103         data |= calc_data;
 104
 105         ret = data;
 106
 107 err:
 108         mutex_unlock(&hwmon->irq_lock);
 109         return ret;
 110 }
 111
 112 static irqreturn_t da9055_auxadc_irq(int irq, void *irq_data)
 113 {
 114         struct da9055_hwmon *hwmon = irq_data;
 115
 116         complete(&hwmon->done);
 117
 118         return IRQ_HANDLED;
 119 }
 120
 121 /* Conversion function for VSYS and ADCINx */
 122 static inline int volt_reg_to_mv(int value, int channel)
 123 {
 124         if (channel == DA9055_ADC_VSYS)
 125                 return DIV_ROUND_CLOSEST(value * 1000, DA9055_VSYS_DIV) + 2500;
 126         else
 127                 return DIV_ROUND_CLOSEST(value * 1000, DA9055_ADCIN_DIV);
 128 }
 129
 130 static int da9055_enable_auto_mode(struct da9055 *da9055, int channel)
 131 {
 132
 133         return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel,
 134                                 1 << channel);
 135
 136 }
 137
 138 static int da9055_disable_auto_mode(struct da9055 *da9055, int channel)
 139 {
 140
 141         return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel, 0);
 142 }
 143
 144 static ssize_t da9055_read_auto_ch(struct device *dev,
 145                                 struct device_attribute *devattr, char *buf)
 146 {
 147         struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
 148         int ret, adc;
 149         int channel = to_sensor_dev_attr(devattr)->index;
 150
 151         mutex_lock(&hwmon->hwmon_lock);
 152
 153         ret = da9055_enable_auto_mode(hwmon->da9055, channel);
 154         if (ret < 0)
 155                 goto hwmon_err;
 156
 157         usleep_range(10000, 10500);
 158
 159         adc = da9055_reg_read(hwmon->da9055, DA9055_REG_VSYS_RES + channel);
 160         if (adc < 0) {
 161                 ret = adc;
 162                 goto hwmon_err_release;
 163         }
 164
 165         ret = da9055_disable_auto_mode(hwmon->da9055, channel);
 166         if (ret < 0)
 167                 goto hwmon_err;
 168
 169         mutex_unlock(&hwmon->hwmon_lock);
 170
 171         return sprintf(buf, "%d\n", volt_reg_to_mv(adc, channel));
 172
 173 hwmon_err_release:
 174         da9055_disable_auto_mode(hwmon->da9055, channel);
 175 hwmon_err:
 176         mutex_unlock(&hwmon->hwmon_lock);
 177         return ret;
 178 }
 179
 180 static ssize_t da9055_read_tjunc(struct device *dev,
 181                                  struct device_attribute *devattr, char *buf)
 182 {
 183         struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
 184         int tjunc;
 185         int toffset;
 186
 187         tjunc = da9055_adc_manual_read(hwmon, DA9055_ADC_TJUNC);
 188         if (tjunc < 0)
 189                 return tjunc;
 190
 191         toffset = da9055_reg_read(hwmon->da9055, DA9055_REG_T_OFFSET);
 192         if (toffset < 0)
 193                 return toffset;
 194
 195         /*
 196          * Degrees celsius = -0.4084 * (ADC_RES - T_OFFSET) + 307.6332
 197          * T_OFFSET is a trim value used to improve accuracy of the result
 198          */
 199         return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(-4084 * (tjunc - toffset)
 200                                                         + 3076332, 10000));
 201 }
 202
 203 static ssize_t da9055_hwmon_show_name(struct device *dev,
 204                                       struct device_attribute *devattr,
 205                                       char *buf)
 206 {
 207         return sprintf(buf, "da9055-hwmon\n");
 208 }
 209
 210 static ssize_t show_label(struct device *dev,
 211                           struct device_attribute *devattr, char *buf)
 212 {
 213         return sprintf(buf, "%s\n",
 214                        input_names[to_sensor_dev_attr(devattr)->index]);
 215 }
 216
 217 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, da9055_read_auto_ch, NULL,
 218                           DA9055_ADC_VSYS);
 219 static SENSOR_DEVICE_ATTR(in0_label, S_IRUGO, show_label, NULL,
 220                           DA9055_ADC_VSYS);
 221 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, da9055_read_auto_ch, NULL,
 222                           DA9055_ADC_ADCIN1);
 223 static SENSOR_DEVICE_ATTR(in1_label, S_IRUGO, show_label, NULL,
 224                           DA9055_ADC_ADCIN1);
 225 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, da9055_read_auto_ch, NULL,
 226                           DA9055_ADC_ADCIN2);
 227 static SENSOR_DEVICE_ATTR(in2_label, S_IRUGO, show_label, NULL,
 228                           DA9055_ADC_ADCIN2);
 229 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, da9055_read_auto_ch, NULL,
 230                           DA9055_ADC_ADCIN3);
 231 static SENSOR_DEVICE_ATTR(in3_label, S_IRUGO, show_label, NULL,
 232                           DA9055_ADC_ADCIN3);
 233
 234 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, da9055_read_tjunc, NULL,
 235                           DA9055_ADC_TJUNC);
 236 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
 237                           DA9055_ADC_TJUNC);
 238
 239 static DEVICE_ATTR(name, S_IRUGO, da9055_hwmon_show_name, NULL);
 240
 241 static struct attribute *da9055_attr[] = {
 242         &dev_attr_name.attr,
 243         &sensor_dev_attr_in0_input.dev_attr.attr,
 244         &sensor_dev_attr_in0_label.dev_attr.attr,
 245         &sensor_dev_attr_in1_input.dev_attr.attr,
 246         &sensor_dev_attr_in1_label.dev_attr.attr,
 247         &sensor_dev_attr_in2_input.dev_attr.attr,
 248         &sensor_dev_attr_in2_label.dev_attr.attr,
 249         &sensor_dev_attr_in3_input.dev_attr.attr,
 250         &sensor_dev_attr_in3_label.dev_attr.attr,
 251
 252         &sensor_dev_attr_temp1_input.dev_attr.attr,
 253         &sensor_dev_attr_temp1_label.dev_attr.attr,
 254         NULL
 255 };
 256
 257 static const struct attribute_group da9055_attr_group = {.attrs = da9055_attr};
 258
 259 static int da9055_hwmon_probe(struct platform_device *pdev)
 260 {
 261         struct da9055_hwmon *hwmon;
 262         int hwmon_irq, ret;
 263
 264         hwmon = devm_kzalloc(&pdev->dev, sizeof(struct da9055_hwmon),
 265                              GFP_KERNEL);
 266         if (!hwmon)
 267                 return -ENOMEM;
 268
 269         mutex_init(&hwmon->hwmon_lock);
 270         mutex_init(&hwmon->irq_lock);
 271
 272         init_completion(&hwmon->done);
 273         hwmon->da9055 = dev_get_drvdata(pdev->dev.parent);
 274
 275         platform_set_drvdata(pdev, hwmon);
 276
 277         hwmon_irq = platform_get_irq_byname(pdev, "HWMON");
 278         if (hwmon_irq < 0)
 279                 return hwmon_irq;
 280
 281         ret = devm_request_threaded_irq(&pdev->dev, hwmon_irq,
 282                                         NULL, da9055_auxadc_irq,
 283                                         IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 284                                         "adc-irq", hwmon);
 285         if (ret != 0) {
 286                 dev_err(hwmon->da9055->dev, "DA9055 ADC IRQ failed ret=%d\n",
 287                         ret);
 288                 return ret;
 289         }
 290
 291         ret = sysfs_create_group(&pdev->dev.kobj, &da9055_attr_group);
 292         if (ret)
 293                 return ret;
 294
 295         hwmon->class_device = hwmon_device_register(&pdev->dev);
 296         if (IS_ERR(hwmon->class_device)) {
 297                 ret = PTR_ERR(hwmon->class_device);
 298                 goto err;
 299         }
 300
 301         return 0;
 302
 303 err:
 304         sysfs_remove_group(&pdev->dev.kobj, &da9055_attr_group);
 305         return ret;
 306 }
 307
 308 static int da9055_hwmon_remove(struct platform_device *pdev)
 309 {
 310         struct da9055_hwmon *hwmon = platform_get_drvdata(pdev);
 311
 312         sysfs_remove_group(&pdev->dev.kobj, &da9055_attr_group);
 313         hwmon_device_unregister(hwmon->class_device);
 314
 315         return 0;
 316 }
 317
 318 static struct platform_driver da9055_hwmon_driver = {
 319         .probe = da9055_hwmon_probe,
 320         .remove = da9055_hwmon_remove,
 321         .driver = {
 322                 .name = "da9055-hwmon",
 323                 .owner = THIS_MODULE,
 324         },
 325 };
 326
 327 module_platform_driver(da9055_hwmon_driver);
 328
 329 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 330 MODULE_DESCRIPTION("DA9055 HWMON driver");
 331 MODULE_LICENSE("GPL");
 332 MODULE_ALIAS("platform:da9055-hwmon");