linux/drivers/hwmon/mc13783-adc.c
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   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Driver for the ADC on Freescale Semiconductor MC13783 and MC13892 PMICs.
   4 *
   5 * Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
   6 * Copyright (C) 2009 Sascha Hauer, Pengutronix
   7 */
   8
   9#include <linux/mfd/mc13xxx.h>
  10#include <linux/platform_device.h>
  11#include <linux/hwmon-sysfs.h>
  12#include <linux/kernel.h>
  13#include <linux/module.h>
  14#include <linux/mod_devicetable.h>
  15#include <linux/hwmon.h>
  16#include <linux/slab.h>
  17#include <linux/init.h>
  18#include <linux/err.h>
  19
  20#define DRIVER_NAME     "mc13783-adc"
  21
  22/* platform device id driver data */
  23#define MC13783_ADC_16CHANS     1
  24#define MC13783_ADC_BPDIV2      2
  25
  26struct mc13783_adc_priv {
  27        struct mc13xxx *mc13xxx;
  28        struct device *hwmon_dev;
  29        char name[PLATFORM_NAME_SIZE];
  30};
  31
  32static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
  33                         char *buf)
  34{
  35        struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
  36
  37        return sprintf(buf, "%s\n", priv->name);
  38}
  39
  40static int mc13783_adc_read(struct device *dev,
  41                struct device_attribute *devattr, unsigned int *val)
  42{
  43        struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
  44        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
  45        unsigned int channel = attr->index;
  46        unsigned int sample[4];
  47        int ret;
  48
  49        ret = mc13xxx_adc_do_conversion(priv->mc13xxx,
  50                        MC13XXX_ADC_MODE_MULT_CHAN,
  51                        channel, 0, 0, sample);
  52        if (ret)
  53                return ret;
  54
  55        /* ADIN7 subchannels */
  56        if (channel >= 16)
  57                channel = 7;
  58
  59        channel &= 0x7;
  60
  61        *val = (sample[channel % 4] >> (channel > 3 ? 14 : 2)) & 0x3ff;
  62
  63        return 0;
  64}
  65
  66static ssize_t mc13783_adc_bp_show(struct device *dev,
  67                                   struct device_attribute *devattr,
  68                                   char *buf)
  69{
  70        unsigned val;
  71        struct platform_device *pdev = to_platform_device(dev);
  72        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
  73        int ret = mc13783_adc_read(dev, devattr, &val);
  74
  75        if (ret)
  76                return ret;
  77
  78        if (driver_data & MC13783_ADC_BPDIV2)
  79                val = DIV_ROUND_CLOSEST(val * 9, 2);
  80        else
  81                /*
  82                 * BP (channel 2) reports with offset 2.4V to the actual value
  83                 * to fit the input range of the ADC.  unit = 2.25mV = 9/4 mV.
  84                 */
  85                val = DIV_ROUND_CLOSEST(val * 9, 4) + 2400;
  86
  87        return sprintf(buf, "%u\n", val);
  88}
  89
  90static ssize_t mc13783_adc_gp_show(struct device *dev,
  91                                   struct device_attribute *devattr,
  92                                   char *buf)
  93{
  94        unsigned val;
  95        int ret = mc13783_adc_read(dev, devattr, &val);
  96
  97        if (ret)
  98                return ret;
  99
 100        /*
 101         * input range is [0, 2.3V], val has 10 bits, so each bit
 102         * is worth 9/4 mV.
 103         */
 104        val = DIV_ROUND_CLOSEST(val * 9, 4);
 105
 106        return sprintf(buf, "%u\n", val);
 107}
 108
 109static ssize_t mc13783_adc_uid_show(struct device *dev,
 110                                    struct device_attribute *devattr,
 111                                    char *buf)
 112{
 113        unsigned int val;
 114        struct platform_device *pdev = to_platform_device(dev);
 115        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
 116        int ret = mc13783_adc_read(dev, devattr, &val);
 117
 118        if (ret)
 119                return ret;
 120
 121        if (driver_data & MC13783_ADC_BPDIV2)
 122                /* MC13892 have 1/2 divider, input range is [0, 4.800V] */
 123                val = DIV_ROUND_CLOSEST(val * 4800, 1024);
 124        else
 125                /* MC13783 have 0.9 divider, input range is [0, 2.555V] */
 126                val = DIV_ROUND_CLOSEST(val * 2555, 1024);
 127
 128        return sprintf(buf, "%u\n", val);
 129}
 130
 131static ssize_t mc13783_adc_temp_show(struct device *dev,
 132                                     struct device_attribute *devattr,
 133                                     char *buf)
 134{
 135        unsigned int val;
 136        struct platform_device *pdev = to_platform_device(dev);
 137        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
 138        int ret = mc13783_adc_read(dev, devattr, &val);
 139
 140        if (ret)
 141                return ret;
 142
 143        if (driver_data & MC13783_ADC_BPDIV2) {
 144                /*
 145                 * MC13892:
 146                 * Die Temperature Read Out Code at 25C 680
 147                 * Temperature change per LSB +0.4244C
 148                 */
 149                ret = DIV_ROUND_CLOSEST(-2635920 + val * 4244, 10);
 150        } else {
 151                /*
 152                 * MC13783:
 153                 * Die Temperature Read Out Code at 25C 282
 154                 * Temperature change per LSB -1.14C
 155                 */
 156                ret = 346480 - 1140 * val;
 157        }
 158
 159        return sprintf(buf, "%d\n", ret);
 160}
 161
 162static DEVICE_ATTR_RO(name);
 163static SENSOR_DEVICE_ATTR_RO(in2_input, mc13783_adc_bp, 2);
 164static SENSOR_DEVICE_ATTR_RO(in5_input, mc13783_adc_gp, 5);
 165static SENSOR_DEVICE_ATTR_RO(in6_input, mc13783_adc_gp, 6);
 166static SENSOR_DEVICE_ATTR_RO(in7_input, mc13783_adc_gp, 7);
 167static SENSOR_DEVICE_ATTR_RO(in8_input, mc13783_adc_gp, 8);
 168static SENSOR_DEVICE_ATTR_RO(in9_input, mc13783_adc_gp, 9);
 169static SENSOR_DEVICE_ATTR_RO(in10_input, mc13783_adc_gp, 10);
 170static SENSOR_DEVICE_ATTR_RO(in11_input, mc13783_adc_gp, 11);
 171static SENSOR_DEVICE_ATTR_RO(in12_input, mc13783_adc_gp, 12);
 172static SENSOR_DEVICE_ATTR_RO(in13_input, mc13783_adc_gp, 13);
 173static SENSOR_DEVICE_ATTR_RO(in14_input, mc13783_adc_gp, 14);
 174static SENSOR_DEVICE_ATTR_RO(in15_input, mc13783_adc_gp, 15);
 175static SENSOR_DEVICE_ATTR_RO(in16_input, mc13783_adc_uid, 16);
 176static SENSOR_DEVICE_ATTR_RO(temp1_input, mc13783_adc_temp, 17);
 177
 178static struct attribute *mc13783_attr_base[] = {
 179        &dev_attr_name.attr,
 180        &sensor_dev_attr_in2_input.dev_attr.attr,
 181        &sensor_dev_attr_in5_input.dev_attr.attr,
 182        &sensor_dev_attr_in6_input.dev_attr.attr,
 183        &sensor_dev_attr_in7_input.dev_attr.attr,
 184        &sensor_dev_attr_in16_input.dev_attr.attr,
 185        &sensor_dev_attr_temp1_input.dev_attr.attr,
 186        NULL
 187};
 188
 189static const struct attribute_group mc13783_group_base = {
 190        .attrs = mc13783_attr_base,
 191};
 192
 193/* these are only used if MC13783_ADC_16CHANS is provided in driver data */
 194static struct attribute *mc13783_attr_16chans[] = {
 195        &sensor_dev_attr_in8_input.dev_attr.attr,
 196        &sensor_dev_attr_in9_input.dev_attr.attr,
 197        &sensor_dev_attr_in10_input.dev_attr.attr,
 198        &sensor_dev_attr_in11_input.dev_attr.attr,
 199        NULL
 200};
 201
 202static const struct attribute_group mc13783_group_16chans = {
 203        .attrs = mc13783_attr_16chans,
 204};
 205
 206/* last four channels may be occupied by the touchscreen */
 207static struct attribute *mc13783_attr_ts[] = {
 208        &sensor_dev_attr_in12_input.dev_attr.attr,
 209        &sensor_dev_attr_in13_input.dev_attr.attr,
 210        &sensor_dev_attr_in14_input.dev_attr.attr,
 211        &sensor_dev_attr_in15_input.dev_attr.attr,
 212        NULL
 213};
 214
 215static const struct attribute_group mc13783_group_ts = {
 216        .attrs = mc13783_attr_ts,
 217};
 218
 219static int mc13783_adc_use_touchscreen(struct platform_device *pdev)
 220{
 221        struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
 222        unsigned flags = mc13xxx_get_flags(priv->mc13xxx);
 223
 224        return flags & MC13XXX_USE_TOUCHSCREEN;
 225}
 226
 227static int __init mc13783_adc_probe(struct platform_device *pdev)
 228{
 229        struct mc13783_adc_priv *priv;
 230        int ret;
 231        const struct platform_device_id *id = platform_get_device_id(pdev);
 232        char *dash;
 233
 234        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
 235        if (!priv)
 236                return -ENOMEM;
 237
 238        priv->mc13xxx = dev_get_drvdata(pdev->dev.parent);
 239        snprintf(priv->name, ARRAY_SIZE(priv->name), "%s", id->name);
 240        dash = strchr(priv->name, '-');
 241        if (dash)
 242                *dash = '\0';
 243
 244        platform_set_drvdata(pdev, priv);
 245
 246        /* Register sysfs hooks */
 247        ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_base);
 248        if (ret)
 249                return ret;
 250
 251        if (id->driver_data & MC13783_ADC_16CHANS) {
 252                ret = sysfs_create_group(&pdev->dev.kobj,
 253                                &mc13783_group_16chans);
 254                if (ret)
 255                        goto out_err_create_16chans;
 256        }
 257
 258        if (!mc13783_adc_use_touchscreen(pdev)) {
 259                ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_ts);
 260                if (ret)
 261                        goto out_err_create_ts;
 262        }
 263
 264        priv->hwmon_dev = hwmon_device_register(&pdev->dev);
 265        if (IS_ERR(priv->hwmon_dev)) {
 266                ret = PTR_ERR(priv->hwmon_dev);
 267                dev_err(&pdev->dev,
 268                                "hwmon_device_register failed with %d.\n", ret);
 269                goto out_err_register;
 270        }
 271
 272        return 0;
 273
 274out_err_register:
 275
 276        if (!mc13783_adc_use_touchscreen(pdev))
 277                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
 278out_err_create_ts:
 279
 280        if (id->driver_data & MC13783_ADC_16CHANS)
 281                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
 282out_err_create_16chans:
 283
 284        sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
 285        return ret;
 286}
 287
 288static int mc13783_adc_remove(struct platform_device *pdev)
 289{
 290        struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
 291        kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
 292
 293        hwmon_device_unregister(priv->hwmon_dev);
 294
 295        if (!mc13783_adc_use_touchscreen(pdev))
 296                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
 297
 298        if (driver_data & MC13783_ADC_16CHANS)
 299                sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
 300
 301        sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
 302
 303        return 0;
 304}
 305
 306static const struct platform_device_id mc13783_adc_idtable[] = {
 307        {
 308                .name = "mc13783-adc",
 309                .driver_data = MC13783_ADC_16CHANS,
 310        }, {
 311                .name = "mc13892-adc",
 312                .driver_data = MC13783_ADC_BPDIV2,
 313        }, {
 314                /* sentinel */
 315        }
 316};
 317MODULE_DEVICE_TABLE(platform, mc13783_adc_idtable);
 318
 319static struct platform_driver mc13783_adc_driver = {
 320        .remove         = mc13783_adc_remove,
 321        .driver         = {
 322                .name   = DRIVER_NAME,
 323        },
 324        .id_table       = mc13783_adc_idtable,
 325};
 326
 327module_platform_driver_probe(mc13783_adc_driver, mc13783_adc_probe);
 328
 329MODULE_DESCRIPTION("MC13783 ADC driver");
 330MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
 331MODULE_LICENSE("GPL");
 332
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