drivers/hwmon/adt7310.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * ADT7310/ADT7310 digital temperature sensor driver
   4  *
   5  * Copyright 2012-2013 Analog Devices Inc.
   6  *   Author: Lars-Peter Clausen <lars@metafoo.de>
   7  */
   8
   9 #include <linux/module.h>
  10 #include <linux/init.h>
  11 #include <linux/regmap.h>
  12 #include <linux/spi/spi.h>
  13 #include <asm/unaligned.h>
  14
  15 #include "adt7x10.h"
  16
  17 #define ADT7310_STATUS                  0
  18 #define ADT7310_CONFIG                  1
  19 #define ADT7310_TEMPERATURE             2
  20 #define ADT7310_ID                      3
  21 #define ADT7310_T_CRIT                  4
  22 #define ADT7310_T_HYST                  5
  23 #define ADT7310_T_ALARM_HIGH            6
  24 #define ADT7310_T_ALARM_LOW             7
  25
  26 static const u8 adt7310_reg_table[] = {
  27         [ADT7X10_TEMPERATURE]   = ADT7310_TEMPERATURE,
  28         [ADT7X10_STATUS]        = ADT7310_STATUS,
  29         [ADT7X10_CONFIG]        = ADT7310_CONFIG,
  30         [ADT7X10_T_ALARM_HIGH]  = ADT7310_T_ALARM_HIGH,
  31         [ADT7X10_T_ALARM_LOW]   = ADT7310_T_ALARM_LOW,
  32         [ADT7X10_T_CRIT]        = ADT7310_T_CRIT,
  33         [ADT7X10_T_HYST]        = ADT7310_T_HYST,
  34         [ADT7X10_ID]            = ADT7310_ID,
  35 };
  36
  37 #define ADT7310_CMD_REG_OFFSET  3
  38 #define ADT7310_CMD_READ        0x40
  39
  40 #define AD7310_COMMAND(reg) (adt7310_reg_table[(reg)] << ADT7310_CMD_REG_OFFSET)
  41
  42 static int adt7310_spi_read_word(struct spi_device *spi, u8 reg)
  43 {
  44         return spi_w8r16be(spi, AD7310_COMMAND(reg) | ADT7310_CMD_READ);
  45 }
  46
  47 static int adt7310_spi_write_word(struct spi_device *spi, u8 reg, u16 data)
  48 {
  49         u8 buf[3];
  50
  51         buf[0] = AD7310_COMMAND(reg);
  52         put_unaligned_be16(data, &buf[1]);
  53
  54         return spi_write(spi, buf, sizeof(buf));
  55 }
  56
  57 static int adt7310_spi_read_byte(struct spi_device *spi, u8 reg)
  58 {
  59         return spi_w8r8(spi, AD7310_COMMAND(reg) | ADT7310_CMD_READ);
  60 }
  61
  62 static int adt7310_spi_write_byte(struct spi_device *spi, u8 reg, u8 data)
  63 {
  64         u8 buf[2];
  65
  66         buf[0] = AD7310_COMMAND(reg);
  67         buf[1] = data;
  68
  69         return spi_write(spi, buf, sizeof(buf));
  70 }
  71
  72 static bool adt7310_regmap_is_volatile(struct device *dev, unsigned int reg)
  73 {
  74         switch (reg) {
  75         case ADT7X10_TEMPERATURE:
  76         case ADT7X10_STATUS:
  77                 return true;
  78         default:
  79                 return false;
  80         }
  81 }
  82
  83 static int adt7310_reg_read(void *context, unsigned int reg, unsigned int *val)
  84 {
  85         struct spi_device *spi = context;
  86         int regval;
  87
  88         switch (reg) {
  89         case ADT7X10_TEMPERATURE:
  90         case ADT7X10_T_ALARM_HIGH:
  91         case ADT7X10_T_ALARM_LOW:
  92         case ADT7X10_T_CRIT:
  93                 regval = adt7310_spi_read_word(spi, reg);
  94                 break;
  95         default:
  96                 regval = adt7310_spi_read_byte(spi, reg);
  97                 break;
  98         }
  99         if (regval < 0)
 100                 return regval;
 101         *val = regval;
 102         return 0;
 103 }
 104
 105 static int adt7310_reg_write(void *context, unsigned int reg, unsigned int val)
 106 {
 107         struct spi_device *spi = context;
 108         int ret;
 109
 110         switch (reg) {
 111         case ADT7X10_TEMPERATURE:
 112         case ADT7X10_T_ALARM_HIGH:
 113         case ADT7X10_T_ALARM_LOW:
 114         case ADT7X10_T_CRIT:
 115                 ret = adt7310_spi_write_word(spi, reg, val);
 116                 break;
 117         default:
 118                 ret = adt7310_spi_write_byte(spi, reg, val);
 119                 break;
 120         }
 121         return ret;
 122 }
 123
 124 static const struct regmap_config adt7310_regmap_config = {
 125         .reg_bits = 8,
 126         .val_bits = 16,
 127         .cache_type = REGCACHE_RBTREE,
 128         .volatile_reg = adt7310_regmap_is_volatile,
 129         .reg_read = adt7310_reg_read,
 130         .reg_write = adt7310_reg_write,
 131 };
 132
 133 static int adt7310_spi_probe(struct spi_device *spi)
 134 {
 135         struct regmap *regmap;
 136
 137         regmap = devm_regmap_init(&spi->dev, NULL, spi, &adt7310_regmap_config);
 138         if (IS_ERR(regmap))
 139                 return PTR_ERR(regmap);
 140
 141         return adt7x10_probe(&spi->dev, spi_get_device_id(spi)->name, spi->irq,
 142                              regmap);
 143 }
 144
 145 static const struct spi_device_id adt7310_id[] = {
 146         { "adt7310", 0 },
 147         { "adt7320", 0 },
 148         {}
 149 };
 150 MODULE_DEVICE_TABLE(spi, adt7310_id);
 151
 152 static struct spi_driver adt7310_driver = {
 153         .driver = {
 154                 .name   = "adt7310",
 155                 .pm     = ADT7X10_DEV_PM_OPS,
 156         },
 157         .probe          = adt7310_spi_probe,
 158         .id_table       = adt7310_id,
 159 };
 160 module_spi_driver(adt7310_driver);
 161
 162 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
 163 MODULE_DESCRIPTION("ADT7310/ADT7320 driver");
 164 MODULE_LICENSE("GPL");