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 <linux/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
 26static 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
 42static 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
 47static 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
 57static 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
 62static 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
 72static 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
 83static 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
105static 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
124static const struct regmap_config adt7310_regmap_config = {
125	.reg_bits = 8,
126	.val_bits = 16,
127	.cache_type = REGCACHE_MAPLE,
128	.volatile_reg = adt7310_regmap_is_volatile,
129	.reg_read = adt7310_reg_read,
130	.reg_write = adt7310_reg_write,
131};
132
133static 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
145static const struct spi_device_id adt7310_id[] = {
146	{ "adt7310", 0 },
147	{ "adt7320", 0 },
148	{}
149};
150MODULE_DEVICE_TABLE(spi, adt7310_id);
151
152static struct spi_driver adt7310_driver = {
153	.driver = {
154		.name	= "adt7310",
155		.pm	= pm_sleep_ptr(&adt7x10_dev_pm_ops),
156	},
157	.probe		= adt7310_spi_probe,
158	.id_table	= adt7310_id,
159};
160module_spi_driver(adt7310_driver);
161
162MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
163MODULE_DESCRIPTION("ADT7310/ADT7320 driver");
164MODULE_LICENSE("GPL");