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
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");
165