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"); 165