1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Analog Devices AD7091R8 12-bit SAR ADC driver
4 *
5 * Copyright 2023 Analog Devices Inc.
6 */
7
8 #include <linux/bitfield.h>
9 #include <linux/iio/iio.h>
10 #include <linux/module.h>
11 #include <linux/regmap.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/spi/spi.h>
14
15 #include "ad7091r-base.h"
16
17 #define AD7091R8_REG_ADDR_MSK GENMASK(15, 11)
18 #define AD7091R8_RD_WR_FLAG_MSK BIT(10)
19 #define AD7091R8_REG_DATA_MSK GENMASK(9, 0)
20
21 #define AD7091R_SPI_REGMAP_CONFIG(n) { \
22 .reg_bits = 8, \
23 .val_bits = 16, \
24 .volatile_reg = ad7091r_volatile_reg, \
25 .writeable_reg = ad7091r_writeable_reg, \
26 .max_register = AD7091R_REG_CH_HYSTERESIS(n), \
27 }
28
ad7091r8_set_mode(struct ad7091r_state * st,enum ad7091r_mode mode)29 static int ad7091r8_set_mode(struct ad7091r_state *st, enum ad7091r_mode mode)
30 {
31 /* AD7091R-2/-4/-8 don't set sample/command/autocycle mode in conf reg */
32 st->mode = mode;
33 return 0;
34 }
35
ad7091r8_reg_result_chan_id(unsigned int val)36 static unsigned int ad7091r8_reg_result_chan_id(unsigned int val)
37 {
38 return AD7091R8_REG_RESULT_CH_ID(val);
39 }
40
41 #define AD7091R_SPI_CHIP_INFO(_n, _name) { \
42 .name = _name, \
43 .channels = ad7091r##_n##_channels, \
44 .num_channels = ARRAY_SIZE(ad7091r##_n##_channels), \
45 .vref_mV = 2500, \
46 .reg_result_chan_id = &ad7091r8_reg_result_chan_id, \
47 .set_mode = &ad7091r8_set_mode, \
48 }
49
50 #define AD7091R_SPI_CHIP_INFO_IRQ(_n, _name) { \
51 .name = _name, \
52 .channels = ad7091r##_n##_channels_irq, \
53 .num_channels = ARRAY_SIZE(ad7091r##_n##_channels_irq), \
54 .vref_mV = 2500, \
55 .reg_result_chan_id = &ad7091r8_reg_result_chan_id, \
56 .set_mode = &ad7091r8_set_mode, \
57 }
58
59 enum ad7091r8_info_ids {
60 AD7091R2_INFO,
61 AD7091R4_INFO,
62 AD7091R4_INFO_IRQ,
63 AD7091R8_INFO,
64 AD7091R8_INFO_IRQ,
65 };
66
67 static const struct iio_chan_spec ad7091r2_channels[] = {
68 AD7091R_CHANNEL(0, 12, NULL, 0),
69 AD7091R_CHANNEL(1, 12, NULL, 0),
70 };
71
72 static const struct iio_chan_spec ad7091r4_channels[] = {
73 AD7091R_CHANNEL(0, 12, NULL, 0),
74 AD7091R_CHANNEL(1, 12, NULL, 0),
75 AD7091R_CHANNEL(2, 12, NULL, 0),
76 AD7091R_CHANNEL(3, 12, NULL, 0),
77 };
78
79 static const struct iio_chan_spec ad7091r4_channels_irq[] = {
80 AD7091R_CHANNEL(0, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
81 AD7091R_CHANNEL(1, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
82 AD7091R_CHANNEL(2, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
83 AD7091R_CHANNEL(3, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
84 };
85
86 static const struct iio_chan_spec ad7091r8_channels[] = {
87 AD7091R_CHANNEL(0, 12, NULL, 0),
88 AD7091R_CHANNEL(1, 12, NULL, 0),
89 AD7091R_CHANNEL(2, 12, NULL, 0),
90 AD7091R_CHANNEL(3, 12, NULL, 0),
91 AD7091R_CHANNEL(4, 12, NULL, 0),
92 AD7091R_CHANNEL(5, 12, NULL, 0),
93 AD7091R_CHANNEL(6, 12, NULL, 0),
94 AD7091R_CHANNEL(7, 12, NULL, 0),
95 };
96
97 static const struct iio_chan_spec ad7091r8_channels_irq[] = {
98 AD7091R_CHANNEL(0, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
99 AD7091R_CHANNEL(1, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
100 AD7091R_CHANNEL(2, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
101 AD7091R_CHANNEL(3, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
102 AD7091R_CHANNEL(4, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
103 AD7091R_CHANNEL(5, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
104 AD7091R_CHANNEL(6, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
105 AD7091R_CHANNEL(7, 12, ad7091r_events, ARRAY_SIZE(ad7091r_events)),
106 };
107
ad7091r_pulse_convst(struct ad7091r_state * st)108 static void ad7091r_pulse_convst(struct ad7091r_state *st)
109 {
110 gpiod_set_value_cansleep(st->convst_gpio, 1);
111 gpiod_set_value_cansleep(st->convst_gpio, 0);
112 }
113
ad7091r_regmap_bus_reg_read(void * context,unsigned int reg,unsigned int * val)114 static int ad7091r_regmap_bus_reg_read(void *context, unsigned int reg,
115 unsigned int *val)
116 {
117 struct ad7091r_state *st = context;
118 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
119 int ret;
120
121 struct spi_transfer t[] = {
122 {
123 .tx_buf = &st->tx_buf,
124 .len = 2,
125 .cs_change = 1,
126 }, {
127 .rx_buf = &st->rx_buf,
128 .len = 2,
129 }
130 };
131
132 if (reg == AD7091R_REG_RESULT)
133 ad7091r_pulse_convst(st);
134
135 st->tx_buf = cpu_to_be16(reg << 11);
136
137 ret = spi_sync_transfer(spi, t, ARRAY_SIZE(t));
138 if (ret < 0)
139 return ret;
140
141 *val = be16_to_cpu(st->rx_buf);
142 return 0;
143 }
144
ad7091r_regmap_bus_reg_write(void * context,unsigned int reg,unsigned int val)145 static int ad7091r_regmap_bus_reg_write(void *context, unsigned int reg,
146 unsigned int val)
147 {
148 struct ad7091r_state *st = context;
149 struct spi_device *spi = container_of(st->dev, struct spi_device, dev);
150
151 /*
152 * AD7091R-2/-4/-8 protocol (datasheet page 31) is to do a single SPI
153 * transfer with reg address set in bits B15:B11 and value set in B9:B0.
154 */
155 st->tx_buf = cpu_to_be16(FIELD_PREP(AD7091R8_REG_DATA_MSK, val) |
156 FIELD_PREP(AD7091R8_RD_WR_FLAG_MSK, 1) |
157 FIELD_PREP(AD7091R8_REG_ADDR_MSK, reg));
158
159 return spi_write(spi, &st->tx_buf, 2);
160 }
161
162 static const struct regmap_bus ad7091r8_regmap_bus = {
163 .reg_read = ad7091r_regmap_bus_reg_read,
164 .reg_write = ad7091r_regmap_bus_reg_write,
165 .reg_format_endian_default = REGMAP_ENDIAN_BIG,
166 .val_format_endian_default = REGMAP_ENDIAN_BIG,
167 };
168
169 static const struct ad7091r_chip_info ad7091r8_infos[] = {
170 [AD7091R2_INFO] = AD7091R_SPI_CHIP_INFO(2, "ad7091r-2"),
171 [AD7091R4_INFO] = AD7091R_SPI_CHIP_INFO(4, "ad7091r-4"),
172 [AD7091R4_INFO_IRQ] = AD7091R_SPI_CHIP_INFO_IRQ(4, "ad7091r-4"),
173 [AD7091R8_INFO] = AD7091R_SPI_CHIP_INFO(8, "ad7091r-8"),
174 [AD7091R8_INFO_IRQ] = AD7091R_SPI_CHIP_INFO_IRQ(8, "ad7091r-8")
175 };
176
177 static const struct regmap_config ad7091r2_reg_conf = AD7091R_SPI_REGMAP_CONFIG(2);
178 static const struct regmap_config ad7091r4_reg_conf = AD7091R_SPI_REGMAP_CONFIG(4);
179 static const struct regmap_config ad7091r8_reg_conf = AD7091R_SPI_REGMAP_CONFIG(8);
180
ad7091r8_regmap_init(struct ad7091r_state * st,const struct regmap_config * regmap_conf)181 static void ad7091r8_regmap_init(struct ad7091r_state *st,
182 const struct regmap_config *regmap_conf)
183 {
184 st->map = devm_regmap_init(st->dev, &ad7091r8_regmap_bus, st,
185 regmap_conf);
186 }
187
ad7091r8_gpio_setup(struct ad7091r_state * st)188 static int ad7091r8_gpio_setup(struct ad7091r_state *st)
189 {
190 st->convst_gpio = devm_gpiod_get(st->dev, "convst", GPIOD_OUT_LOW);
191 if (IS_ERR(st->convst_gpio))
192 return dev_err_probe(st->dev, PTR_ERR(st->convst_gpio),
193 "Error getting convst GPIO\n");
194
195 st->reset_gpio = devm_gpiod_get_optional(st->dev, "reset",
196 GPIOD_OUT_HIGH);
197 if (IS_ERR(st->reset_gpio))
198 return dev_err_probe(st->dev, PTR_ERR(st->reset_gpio),
199 "Error on requesting reset GPIO\n");
200
201 if (st->reset_gpio) {
202 fsleep(20);
203 gpiod_set_value_cansleep(st->reset_gpio, 0);
204 }
205
206 return 0;
207 }
208
209 static struct ad7091r_init_info ad7091r2_init_info = {
210 .info_no_irq = &ad7091r8_infos[AD7091R2_INFO],
211 .regmap_config = &ad7091r2_reg_conf,
212 .init_adc_regmap = &ad7091r8_regmap_init,
213 .setup = &ad7091r8_gpio_setup
214 };
215
216 static struct ad7091r_init_info ad7091r4_init_info = {
217 .info_no_irq = &ad7091r8_infos[AD7091R4_INFO],
218 .info_irq = &ad7091r8_infos[AD7091R4_INFO_IRQ],
219 .regmap_config = &ad7091r4_reg_conf,
220 .init_adc_regmap = &ad7091r8_regmap_init,
221 .setup = &ad7091r8_gpio_setup
222 };
223
224 static struct ad7091r_init_info ad7091r8_init_info = {
225 .info_no_irq = &ad7091r8_infos[AD7091R8_INFO],
226 .info_irq = &ad7091r8_infos[AD7091R8_INFO_IRQ],
227 .regmap_config = &ad7091r8_reg_conf,
228 .init_adc_regmap = &ad7091r8_regmap_init,
229 .setup = &ad7091r8_gpio_setup
230 };
231
ad7091r8_spi_probe(struct spi_device * spi)232 static int ad7091r8_spi_probe(struct spi_device *spi)
233 {
234 const struct ad7091r_init_info *init_info;
235
236 init_info = spi_get_device_match_data(spi);
237 if (!init_info)
238 return -EINVAL;
239
240 return ad7091r_probe(&spi->dev, init_info, spi->irq);
241 }
242
243 static const struct of_device_id ad7091r8_of_match[] = {
244 { .compatible = "adi,ad7091r2", .data = &ad7091r2_init_info },
245 { .compatible = "adi,ad7091r4", .data = &ad7091r4_init_info },
246 { .compatible = "adi,ad7091r8", .data = &ad7091r8_init_info },
247 { }
248 };
249 MODULE_DEVICE_TABLE(of, ad7091r8_of_match);
250
251 static const struct spi_device_id ad7091r8_spi_id[] = {
252 { "ad7091r2", (kernel_ulong_t)&ad7091r2_init_info },
253 { "ad7091r4", (kernel_ulong_t)&ad7091r4_init_info },
254 { "ad7091r8", (kernel_ulong_t)&ad7091r8_init_info },
255 { }
256 };
257 MODULE_DEVICE_TABLE(spi, ad7091r8_spi_id);
258
259 static struct spi_driver ad7091r8_driver = {
260 .driver = {
261 .name = "ad7091r8",
262 .of_match_table = ad7091r8_of_match,
263 },
264 .probe = ad7091r8_spi_probe,
265 .id_table = ad7091r8_spi_id,
266 };
267 module_spi_driver(ad7091r8_driver);
268
269 MODULE_AUTHOR("Marcelo Schmitt <marcelo.schmitt@analog.com>");
270 MODULE_DESCRIPTION("Analog Devices AD7091R8 ADC driver");
271 MODULE_LICENSE("GPL");
272 MODULE_IMPORT_NS("IIO_AD7091R");
273