1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AD5592R Digital <-> Analog converters driver
4 *
5 * Copyright 2015-2016 Analog Devices Inc.
6 * Author: Paul Cercueil <paul.cercueil@analog.com>
7 */
8
9 #include "ad5592r-base.h"
10
11 #include <linux/bitops.h>
12 #include <linux/module.h>
13 #include <linux/mod_devicetable.h>
14 #include <linux/spi/spi.h>
15
16 #define AD5592R_GPIO_READBACK_EN BIT(10)
17 #define AD5592R_LDAC_READBACK_EN BIT(6)
18
ad5592r_spi_wnop_r16(struct ad5592r_state * st,__be16 * buf)19 static int ad5592r_spi_wnop_r16(struct ad5592r_state *st, __be16 *buf)
20 {
21 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
22 struct spi_transfer t = {
23 .tx_buf = &st->spi_msg_nop,
24 .rx_buf = buf,
25 .len = 2
26 };
27
28 st->spi_msg_nop = 0; /* NOP */
29
30 return spi_sync_transfer(spi, &t, 1);
31 }
32
ad5592r_write_dac(struct ad5592r_state * st,unsigned chan,u16 value)33 static int ad5592r_write_dac(struct ad5592r_state *st, unsigned chan, u16 value)
34 {
35 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
36
37 st->spi_msg = cpu_to_be16(BIT(15) | (chan << 12) | value);
38
39 return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
40 }
41
ad5592r_read_adc(struct ad5592r_state * st,unsigned chan,u16 * value)42 static int ad5592r_read_adc(struct ad5592r_state *st, unsigned chan, u16 *value)
43 {
44 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
45 int ret;
46
47 st->spi_msg = cpu_to_be16((AD5592R_REG_ADC_SEQ << 11) | BIT(chan));
48
49 ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
50 if (ret)
51 return ret;
52
53 /*
54 * Invalid data:
55 * See Figure 40. Single-Channel ADC Conversion Sequence
56 */
57 ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
58 if (ret)
59 return ret;
60
61 ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
62 if (ret)
63 return ret;
64
65 *value = be16_to_cpu(st->spi_msg);
66
67 return 0;
68 }
69
ad5592r_reg_write(struct ad5592r_state * st,u8 reg,u16 value)70 static int ad5592r_reg_write(struct ad5592r_state *st, u8 reg, u16 value)
71 {
72 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
73
74 st->spi_msg = cpu_to_be16((reg << 11) | value);
75
76 return spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
77 }
78
ad5592r_reg_read(struct ad5592r_state * st,u8 reg,u16 * value)79 static int ad5592r_reg_read(struct ad5592r_state *st, u8 reg, u16 *value)
80 {
81 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
82 int ret;
83
84 st->spi_msg = cpu_to_be16((AD5592R_REG_LDAC << 11) |
85 AD5592R_LDAC_READBACK_EN | (reg << 2));
86
87 ret = spi_write(spi, &st->spi_msg, sizeof(st->spi_msg));
88 if (ret)
89 return ret;
90
91 ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
92 if (ret)
93 return ret;
94
95 *value = be16_to_cpu(st->spi_msg);
96
97 return 0;
98 }
99
ad5592r_gpio_read(struct ad5592r_state * st,u8 * value)100 static int ad5592r_gpio_read(struct ad5592r_state *st, u8 *value)
101 {
102 int ret;
103
104 ret = ad5592r_reg_write(st, AD5592R_REG_GPIO_IN_EN,
105 AD5592R_GPIO_READBACK_EN | st->gpio_in);
106 if (ret)
107 return ret;
108
109 ret = ad5592r_spi_wnop_r16(st, &st->spi_msg);
110 if (ret)
111 return ret;
112
113 *value = (u8) be16_to_cpu(st->spi_msg);
114
115 return 0;
116 }
117
118 static const struct ad5592r_rw_ops ad5592r_rw_ops = {
119 .write_dac = ad5592r_write_dac,
120 .read_adc = ad5592r_read_adc,
121 .reg_write = ad5592r_reg_write,
122 .reg_read = ad5592r_reg_read,
123 .gpio_read = ad5592r_gpio_read,
124 };
125
ad5592r_spi_probe(struct spi_device * spi)126 static int ad5592r_spi_probe(struct spi_device *spi)
127 {
128 const struct spi_device_id *id = spi_get_device_id(spi);
129
130 return ad5592r_probe(&spi->dev, id->name, &ad5592r_rw_ops);
131 }
132
ad5592r_spi_remove(struct spi_device * spi)133 static void ad5592r_spi_remove(struct spi_device *spi)
134 {
135 ad5592r_remove(&spi->dev);
136 }
137
138 static const struct spi_device_id ad5592r_spi_ids[] = {
139 { .name = "ad5592r", },
140 {}
141 };
142 MODULE_DEVICE_TABLE(spi, ad5592r_spi_ids);
143
144 static const struct of_device_id ad5592r_of_match[] = {
145 { .compatible = "adi,ad5592r", },
146 {},
147 };
148 MODULE_DEVICE_TABLE(of, ad5592r_of_match);
149
150 static const struct acpi_device_id ad5592r_acpi_match[] = {
151 {"ADS5592", },
152 { },
153 };
154 MODULE_DEVICE_TABLE(acpi, ad5592r_acpi_match);
155
156 static struct spi_driver ad5592r_spi_driver = {
157 .driver = {
158 .name = "ad5592r",
159 .of_match_table = ad5592r_of_match,
160 .acpi_match_table = ad5592r_acpi_match,
161 },
162 .probe = ad5592r_spi_probe,
163 .remove = ad5592r_spi_remove,
164 .id_table = ad5592r_spi_ids,
165 };
166 module_spi_driver(ad5592r_spi_driver);
167
168 MODULE_AUTHOR("Paul Cercueil <paul.cercueil@analog.com>");
169 MODULE_DESCRIPTION("Analog Devices AD5592R multi-channel converters");
170 MODULE_LICENSE("GPL v2");
171 MODULE_IMPORT_NS(IIO_AD5592R);
172