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 mutex    hwmon_lock;
  40         struct mutex    irq_lock;
  41         struct completion done;
  42 };
  43
  44 static const char * const input_names[] = {
  45         [DA9055_ADC_VSYS]       = "VSYS",
  46         [DA9055_ADC_ADCIN1]     = "ADC IN1",
  47         [DA9055_ADC_ADCIN2]     = "ADC IN2",
  48         [DA9055_ADC_ADCIN3]     = "ADC IN3",
  49         [DA9055_ADC_TJUNC]      = "CHIP TEMP",
  50 };
  51
  52 static const u8 chan_mux[DA9055_ADC_TJUNC + 1] = {
  53         [DA9055_ADC_VSYS]       = DA9055_ADC_MUX_VSYS,
  54         [DA9055_ADC_ADCIN1]     = DA9055_ADC_MUX_ADCIN1,
  55         [DA9055_ADC_ADCIN2]     = DA9055_ADC_MUX_ADCIN2,
  56         [DA9055_ADC_ADCIN3]     = DA9055_ADC_MUX_ADCIN3,
  57         [DA9055_ADC_TJUNC]      = DA9055_ADC_MUX_T_SENSE,
  58 };
  59
  60 static int da9055_adc_manual_read(struct da9055_hwmon *hwmon,
  61                                         unsigned char channel)
  62 {
  63         int ret;
  64         unsigned short calc_data;
  65         unsigned short data;
  66         unsigned char mux_sel;
  67         struct da9055 *da9055 = hwmon->da9055;
  68
  69         if (channel > DA9055_ADC_TJUNC)
  70                 return -EINVAL;
  71
  72         mutex_lock(&hwmon->irq_lock);
  73
  74         /* Selects desired MUX for manual conversion */
  75         mux_sel = chan_mux[channel] | DA9055_ADC_MAN_CONV;
  76
  77         ret = da9055_reg_write(da9055, DA9055_REG_ADC_MAN, mux_sel);
  78         if (ret < 0)
  79                 goto err;
  80
  81         /* Wait for an interrupt */
  82         if (!wait_for_completion_timeout(&hwmon->done,
  83                                         msecs_to_jiffies(500))) {
  84                 dev_err(da9055->dev,
  85                         "timeout waiting for ADC conversion interrupt\n");
  86                 ret = -ETIMEDOUT;
  87                 goto err;
  88         }
  89
  90         ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_H);
  91         if (ret < 0)
  92                 goto err;
  93
  94         calc_data = (unsigned short)ret;
  95         data = calc_data << 2;
  96
  97         ret = da9055_reg_read(da9055, DA9055_REG_ADC_RES_L);
  98         if (ret < 0)
  99                 goto err;
 100
 101         calc_data = (unsigned short)(ret & DA9055_ADC_LSB_MASK);
 102         data |= calc_data;
 103
 104         ret = data;
 105
 106 err:
 107         mutex_unlock(&hwmon->irq_lock);
 108         return ret;
 109 }
 110
 111 static irqreturn_t da9055_auxadc_irq(int irq, void *irq_data)
 112 {
 113         struct da9055_hwmon *hwmon = irq_data;
 114
 115         complete(&hwmon->done);
 116
 117         return IRQ_HANDLED;
 118 }
 119
 120 /* Conversion function for VSYS and ADCINx */
 121 static inline int volt_reg_to_mv(int value, int channel)
 122 {
 123         if (channel == DA9055_ADC_VSYS)
 124                 return DIV_ROUND_CLOSEST(value * 1000, DA9055_VSYS_DIV) + 2500;
 125         else
 126                 return DIV_ROUND_CLOSEST(value * 1000, DA9055_ADCIN_DIV);
 127 }
 128
 129 static int da9055_enable_auto_mode(struct da9055 *da9055, int channel)
 130 {
 131
 132         return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel,
 133                                 1 << channel);
 134
 135 }
 136
 137 static int da9055_disable_auto_mode(struct da9055 *da9055, int channel)
 138 {
 139
 140         return da9055_reg_update(da9055, DA9055_REG_ADC_CONT, 1 << channel, 0);
 141 }
 142
 143 static ssize_t da9055_read_auto_ch(struct device *dev,
 144                                 struct device_attribute *devattr, char *buf)
 145 {
 146         struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
 147         int ret, adc;
 148         int channel = to_sensor_dev_attr(devattr)->index;
 149
 150         mutex_lock(&hwmon->hwmon_lock);
 151
 152         ret = da9055_enable_auto_mode(hwmon->da9055, channel);
 153         if (ret < 0)
 154                 goto hwmon_err;
 155
 156         usleep_range(10000, 10500);
 157
 158         adc = da9055_reg_read(hwmon->da9055, DA9055_REG_VSYS_RES + channel);
 159         if (adc < 0) {
 160                 ret = adc;
 161                 goto hwmon_err_release;
 162         }
 163
 164         ret = da9055_disable_auto_mode(hwmon->da9055, channel);
 165         if (ret < 0)
 166                 goto hwmon_err;
 167
 168         mutex_unlock(&hwmon->hwmon_lock);
 169
 170         return sprintf(buf, "%d\n", volt_reg_to_mv(adc, channel));
 171
 172 hwmon_err_release:
 173         da9055_disable_auto_mode(hwmon->da9055, channel);
 174 hwmon_err:
 175         mutex_unlock(&hwmon->hwmon_lock);
 176         return ret;
 177 }
 178
 179 static ssize_t da9055_read_tjunc(struct device *dev,
 180                                  struct device_attribute *devattr, char *buf)
 181 {
 182         struct da9055_hwmon *hwmon = dev_get_drvdata(dev);
 183         int tjunc;
 184         int toffset;
 185
 186         tjunc = da9055_adc_manual_read(hwmon, DA9055_ADC_TJUNC);
 187         if (tjunc < 0)
 188                 return tjunc;
 189
 190         toffset = da9055_reg_read(hwmon->da9055, DA9055_REG_T_OFFSET);
 191         if (toffset < 0)
 192                 return toffset;
 193
 194         /*
 195          * Degrees celsius = -0.4084 * (ADC_RES - T_OFFSET) + 307.6332
 196          * T_OFFSET is a trim value used to improve accuracy of the result
 197          */
 198         return sprintf(buf, "%d\n", DIV_ROUND_CLOSEST(-4084 * (tjunc - toffset)
 199                                                         + 3076332, 10000));
 200 }
 201
 202 static ssize_t show_label(struct device *dev,
 203                           struct device_attribute *devattr, char *buf)
 204 {
 205         return sprintf(buf, "%s\n",
 206                        input_names[to_sensor_dev_attr(devattr)->index]);
 207 }
 208
 209 static SENSOR_DEVICE_ATTR(in0_input, S_IRUGO, da9055_read_auto_ch, NULL,
 210                           DA9055_ADC_VSYS);
 211 static SENSOR_DEVICE_ATTR(in0_label, S_IRUGO, show_label, NULL,
 212                           DA9055_ADC_VSYS);
 213 static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, da9055_read_auto_ch, NULL,
 214                           DA9055_ADC_ADCIN1);
 215 static SENSOR_DEVICE_ATTR(in1_label, S_IRUGO, show_label, NULL,
 216                           DA9055_ADC_ADCIN1);
 217 static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, da9055_read_auto_ch, NULL,
 218                           DA9055_ADC_ADCIN2);
 219 static SENSOR_DEVICE_ATTR(in2_label, S_IRUGO, show_label, NULL,
 220                           DA9055_ADC_ADCIN2);
 221 static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, da9055_read_auto_ch, NULL,
 222                           DA9055_ADC_ADCIN3);
 223 static SENSOR_DEVICE_ATTR(in3_label, S_IRUGO, show_label, NULL,
 224                           DA9055_ADC_ADCIN3);
 225
 226 static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, da9055_read_tjunc, NULL,
 227                           DA9055_ADC_TJUNC);
 228 static SENSOR_DEVICE_ATTR(temp1_label, S_IRUGO, show_label, NULL,
 229                           DA9055_ADC_TJUNC);
 230
 231 static struct attribute *da9055_attrs[] = {
 232         &sensor_dev_attr_in0_input.dev_attr.attr,
 233         &sensor_dev_attr_in0_label.dev_attr.attr,
 234         &sensor_dev_attr_in1_input.dev_attr.attr,
 235         &sensor_dev_attr_in1_label.dev_attr.attr,
 236         &sensor_dev_attr_in2_input.dev_attr.attr,
 237         &sensor_dev_attr_in2_label.dev_attr.attr,
 238         &sensor_dev_attr_in3_input.dev_attr.attr,
 239         &sensor_dev_attr_in3_label.dev_attr.attr,
 240
 241         &sensor_dev_attr_temp1_input.dev_attr.attr,
 242         &sensor_dev_attr_temp1_label.dev_attr.attr,
 243         NULL
 244 };
 245
 246 ATTRIBUTE_GROUPS(da9055);
 247
 248 static int da9055_hwmon_probe(struct platform_device *pdev)
 249 {
 250         struct device *dev = &pdev->dev;
 251         struct da9055_hwmon *hwmon;
 252         struct device *hwmon_dev;
 253         int hwmon_irq, ret;
 254
 255         hwmon = devm_kzalloc(dev, sizeof(struct da9055_hwmon), GFP_KERNEL);
 256         if (!hwmon)
 257                 return -ENOMEM;
 258
 259         mutex_init(&hwmon->hwmon_lock);
 260         mutex_init(&hwmon->irq_lock);
 261
 262         init_completion(&hwmon->done);
 263         hwmon->da9055 = dev_get_drvdata(pdev->dev.parent);
 264
 265         hwmon_irq = platform_get_irq_byname(pdev, "HWMON");
 266         if (hwmon_irq < 0)
 267                 return hwmon_irq;
 268
 269         ret = devm_request_threaded_irq(&pdev->dev, hwmon_irq,
 270                                         NULL, da9055_auxadc_irq,
 271                                         IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
 272                                         "adc-irq", hwmon);
 273         if (ret != 0) {
 274                 dev_err(hwmon->da9055->dev, "DA9055 ADC IRQ failed ret=%d\n",
 275                         ret);
 276                 return ret;
 277         }
 278
 279         hwmon_dev = devm_hwmon_device_register_with_groups(dev, "da9055",
 280                                                            hwmon,
 281                                                            da9055_groups);
 282         return PTR_ERR_OR_ZERO(hwmon_dev);
 283 }
 284
 285 static struct platform_driver da9055_hwmon_driver = {
 286         .probe = da9055_hwmon_probe,
 287         .driver = {
 288                 .name = "da9055-hwmon",
 289         },
 290 };
 291
 292 module_platform_driver(da9055_hwmon_driver);
 293
 294 MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>");
 295 MODULE_DESCRIPTION("DA9055 HWMON driver");
 296 MODULE_LICENSE("GPL");
 297 MODULE_ALIAS("platform:da9055-hwmon");